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Hi, I'm Bo with Free Code Camp. This network
engineering course was developed by Brian
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Farrell, and instructor with Edmonds college.
It will prepare you to configure, manage and
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troubleshoot computer networks. Also, the
course is a great way to prepare for a comp
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Tia's network plus exam. So let's start. Hello,
I'm Brian ferrill. And welcome to pace I t's
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session on the introduction to network devices,
part one. Today we're going to be talking
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about layer one devices, layer two devices.
And then we're going to conclude with layer
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three devices. There's a fair amount of information
to cover. So let's go ahead and dive into
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this session. Of course, I'm going to begin
with layer one devices. Well, before I start
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talking about the layer one devices, we need
to talk about the open system interconnection
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model, the OSI model, it was developed as
a way to help disparate computing systems
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to communicate with each other. The OSI reference
model has seven layers. layer one is the physical
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layer, layer two is data link. layer three
is network layer four is transport layer five
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is session. Layer six is presentation and
layer seven is application. We're going to
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be discussing the bottom three layers layers
One, two and three today. Now most devices
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do function at more than one layer of the
OSI reference model. But when it comes time
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to determining where they fit into the model,
you must first determine the highest level
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at which they operate, because that's where
they fit into the OSI model. To do that, you
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must know what they do and how that relates
to the OSI model. And with that, let's talk
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about analog modems. The word modem is actually
derived from a contraction of modulator demodulator.
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modems were developed to take a digital signal
coming from a digital node and convert it
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to an analog signal modulating the signal
and placing it on a wire. In return, it would
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accept an analog signal from the wire and
convert it demodulating the signal back to
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a digital signal that the node can understand.
modems were developed to create a connection
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between network segments via the public switched
telephone network using the plain old telephone
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system. Now modems provide for a single connection
to a network. And they're only concerned about
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the wire in the wire resides on the physical
layer layer one of the OSI model, it doesn't
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care where the signal comes from, it just
does its job. Then there's the hub. A hub
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functions as a concentrator or repeater in
that it doesn't care where the signal comes
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from, or where the signal is going. Kind of
like the modem, it takes an electrical signal
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that arrives on a port and replicates that
signal out all of its other ports. hub may
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have just a few ports, or it may have many
ports in for a variety of reasons the hub
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is not very common anymore in the modern network.
So now let's move on to layer two devices.
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The first layer two device that we're going
to talk about is the switch. A switch utilizes
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an application specific integrated circuit
chip and a basic chip. The ASIC chip has specific
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programming that allows the switch to learn
when a device is on the network and which
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ports it is connected to via that devices
layer two MAC address. That's what makes a
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switch a layer two device, a switch may have
just a few ports or it may have many ports,
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kind of like the hub. And although a switches
smarter than a hub, it can still be very simple,
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or it can be highly complex and programmable.
A switch can only communicate with local network
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devices. another layer two device that we
need to talk about our wireless access points.
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The whap whap is a specific type of network
bridge that connects or bridges, wireless
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network segments with wired network segments.
The most common type of web bridges and 802
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dot 11 wireless network segment with an 802
dot three Ethernet network segment just like
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a switch a wire Access Point will only communicate
with local network devices. Now let's move
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on to layer three devices. And First up is
the multi layer switch. A multi layer switch
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provides normal layer two network switching
services, but it will also provide layer three
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or higher OSI model services. The most common
multi layer switch is a layer three switch,
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it not only utilizes an async chip for switching,
but that async chip is also programmed to
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handle routing functions. This allows the
device to communicate and pass data to non
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local network devices. A multi layer switch
is a highly programmable and complex network
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device. A multi layer switch may have just
a few ports, or it may have a lot of ports.
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They're not very common in the small office
home office network. Because they're really
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really expensive, you're more likely to find
them in an enterprise local area network.
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Now let's move on to the router. A router
is the most common network device for connecting
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different networks together, utilizing the
OSI models layer three logical network information.
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That's what makes a router a layer three device.
The router uses software programming for decision
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making, as compared to the switches use of
an ASIC chip. The router uses this programming
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to keep track of different networks in what
it considers to be the best possible route
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to reach those networks. A router can communicate
with both local and non local network devices.
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In most cases, a router will have fewer ports,
then a switch. Now that concludes this session
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on the introduction to network devices. Part
One, we talked about layer one devices. We
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talked about layer two devices. And we concluded
with a couple of layer three devices. Good
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day. I'm Brian ferrill. And welcome to pace
eyeties session on introduction to network
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devices, part two. Today we're going to discuss
some security network devices. And then we'll
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move on to some optimization and performance
devices. And with that, let's go ahead and
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begin this session. And we will begin by talking
about security devices. First up is the firewall.
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Now a firewall can be placed on routers or
hosts in that it can be software based or
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it can be its own device. A firewall functions
at multiple layers of the OSI model, specifically
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at layers 234 and seven. A firewall can block
packets from entering or leaving the network.
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And it does this through one of two methods
it can do it through stateless inspection,
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in which the firewall will examine every packet
that enters or leaves the networks against
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a set of rules. Once the packet matches a
rule, the rule is enforced in the specified
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action is taken, or it may use state full
inspection. This is when a firewall will only
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examine the state of a connection between
networks. Specifically, when a connection
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is made from an internal network to an external
network. The firewall will not examine any
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packets returning from the external connection.
It only cares about the state of the connection.
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As a general rule, external connections are
not allowed to be initiated with the internal
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network. Now firewalls are the first line
of defense in protecting the internal network
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from outside threats. You can consider the
firewall to be the police force of the network.
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Then there is the intrusion detection system.
The IDs and IDs is a passive system designed
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to identify when a network breach or attack
against the network is occurring. They're
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usually designed to inform a network administrator
when a breach or attack has occurred. And
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it does this through log files, text messages
and are through email notification Friends,
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and IDs cannot prevent or stop a breach or
attack on its own. The IBS receives a copy
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of all traffic and evaluates it against a
set of standards. The standards that it used
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may be signature based. This is when it evaluates
network traffic for known malware or attack
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signatures, or the standard may be anomaly
based. This is where it evaluates network
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traffic for suspicious changes, or it may
be policy base. This is where it evaluates
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network traffic against a specific declared
security policy. An IDs may be deployed at
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the host level when it's deployed at the host
level. It's called a host based intrusion
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detection system, we're hids more potent than
the intrusion detection system is the intrusion
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prevention system. The IPS an IPS is an active
system designed to stop a breach or attack
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from succeeding and damaging the network.
They're usually designed to perform an action
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or set of actions to stop the malicious activity.
They will also inform a network administrator
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through the use of log files, SMS, text messaging,
and or through email notification. For an
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IPS to work. All traffic on the network segment
needs to flow through the IPS as it enters
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and leaves the network segment. Like the IDS
all of the traffic is evaluated against a
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set of standards and they're the same standards
that are used on the IDs. The best placement
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on the network segment is between a router
with a firewall hopefully, and the destination
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network segment. That way all the traffic
flows through the IPS. IPS are programmed
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to make an active response to the situation,
they can block the offending IP address, they
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can close down vulnerable interfaces, they
can terminate network sessions, they can redirect
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the attack. Plus there are more actions that
an IPS can take. The main thing is is that
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they are designed to be active to stop the
breach or attack from succeeding and damaging
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your network. Let's move on to the virtual
private network concentrator the VPN concentrator.
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Now this will allow for many secure VPN connections
to a network. The concentrator will provide
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proper tunneling and encryption depending
upon the type of VPN connection that is allowed
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to the network. Most concentrators can function
at multiple layers of the OSI model. Specifically,
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they can operate at layer two, layer three
and layer seven. Now outside of internet transactions,
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which use an SSL VPN connection at layer seven,
most concentrators will function at the network
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layer or layer three of the OSI model, providing
IPsec encryption through a secure tunnel.
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Now let's talk about optimization and performance
devices. We will begin by talking about the
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load balancer. a load balancer may also be
called a content switch or a content filter.
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It's a network appliance that is used to load
balance between multiple hosts that contain
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the same data. This spreads out the workload
for greater efficiency. They're commonly used
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to distribute the requests or workload to
a server farm among the various servers in
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the farm, helping to ensure that no single
server gets overloaded with work requests.
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Then there's the proxy server. A proxy server
is an appliance that requests resources on
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behalf of a client machine. It's often used
to retrieve resources from outside untrusted
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networks on behalf of the requesting client.
It hides and protects that requesting client
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from the outside untrusted network. It can
also be utilized to filter allowed content
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back into the trusted network. It can also
increase network performance by caching or
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saving commonly requested web pages. Now that
concludes this session on the introduction
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to network devices, part two We talked about
some security devices that you may find on
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your network. And we concluded with optimization
and performance devices that may also be present.
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Hello, I'm Brian ferrill. And welcome to pace
I t's session on networking services and applications
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part one. Today I'm going to be discussing
the basics of the virtual private network.
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And then I'm going to move on to protocols
used by virtual private networks. Now, there's
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a whole lot of stuff to cover. So let's go
ahead and begin this session. Of course, I'm
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going to begin by talking about the basics
of the virtual private network. A virtual
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private network or VPN is used by remote hosts
to access a private network through an encrypted
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tunnel through a public network. Once the
VPN connection is made, the remote host is
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no longer considered remote is actually seen
by the private network as being a local host.
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There are many advantages to that, but I'm
not going to cover them right now. Even though
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the network traffic may pass through many
different routes or systems, it's seen by
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both ends as being a direct connection. The
use of the VPN can help to reduce networking
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costs. For organizations and business. The
cost reduction is partially achieved, because
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the VPN doesn't require the use of a dedicated
leased line to create that direct connection.
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There are several different types of VPNs
there is the site to site VPN, which allows
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a remote sites network to connect to the main
sites network and be seen as a local network
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segment. VPN concentrators on both ends of
the VPN will manage that connection. Then
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there's the remote access VPN, which is also
called a host to site VPN. It allows select
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remote users to connect to the local network.
A VPN concentrator on the local network will
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manage the connection coming in from the remote
users. The remote system making the connection
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uses special software called VPN client software
to make that connection. The third type of
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VPN is the host of host VPN, which is often
called an SSL VPN. It allows us secure connection
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between two systems without the use of VPN
client software. A VPN concentrator on the
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local network manages the connection. The
host seeking to connect uses a web browser
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that supports the correct encryption technology,
which is either SSL or more likely TLS. To
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make the connection to the VPN concentrator.
It's time to discuss some protocols used by
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the virtual private network. The big protocol
for VPN is called Internet Protocol security
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IPsec, which isn't actually a protocol in
itself, but a whole set of protocols. IP sec
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works at layer three of the OSI model or above.
It's the most common suite of protocols used
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to secure a VPN connection. IP sec can be
used with the authentication header protocol
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or the H protocol. h only offers authentication
services, but no encryption. So it authentic
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Kate's the user but there is no encryption
of the session, or ipset can be used with
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encapsulating security payload protocol or
the ESP protocol. ESP both authenticates and
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encrypts the packets. It is the most popular
method of securing a VPN connection, both
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H and ESP will operate in one of two modes.
The first mode is transparent mode, that is
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between two devices as in a host to host VPN,
or they can be used in tunnel mode, which
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is between two endpoints as in a site to site
VPN, IP sec implements Internet Security Association
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and key management eisah camp by default eisah
camp provides a method for transferring security
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key and authentication data between systems
outside of the security key generating process.
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It is a much more secure process. Then we
have generic routing encapsulation. gra G
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is a tunneling protocol that is capable of
encapsulating a wide variety of other nuts
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layer protocols, it's often used to create
a sub tunnel within an IP sec connection.
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Why is that? Well, IP sec will only transmit
unicast packets, that's one to one communication.
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In many cases, there is a need to transmit
multicast, which is one to some communication,
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or broadcast, which is one to many communication
packets across an IP set connection. By using
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GRP we can get that accomplished. Then there's
Point to Point tunneling protocol pptp. This
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is an older VPN technology that supports dial
up VPN connections. on its own, it lacked
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native security features, so it wasn't very
secure. But Microsoft's implementation included
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additional security by adding gr E. Two point
to point tunneling protocol. Transport Layer
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Security is another common VPN protocol. TLS
is a cryptographic protocol used to create
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a secure encrypted connection between two
end devices or applications. It uses asymmetrical
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cryptography to authenticate endpoints and
then negotiates a symmetrical security key,
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which is used to encrypt the session TLS has
largely replaced its cousin, secure socket
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layer protocol, and TLS works at layer five
and above of the OSI model. Its most common
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usage is in creating a secure encrypted internet
session or SSL VPN. All modern web browsers
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support TLS now I just mentioned secure socket
layer or SSL. SSL is an older cryptographic
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protocol that is very similar to TLS. The
most common use is in internet transactions.
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Why? Because all modern web browsers support
SSL. But due to issues with earlier versions
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of the protocol, it has largely been replaced
by TLS. SSL version 3.3 has been developed
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to address the weaknesses of earlier versions.
But it may never again catch up to its cousin,
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the TLS protocol. Now that concludes this
session on networking services and applications
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part one, I talked about the basics of the
virtual private network. And then I talked
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about the protocols used by the VPN network.
Good day, I'm Brian ferrill. And welcome to
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pace I t's session on networking services
and applications part two. Today we're going
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to be discussing network access services.
And then we're going to move on to other services
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and applications. As always, there's a fair
amount of ground to cover. So let's go ahead
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and dive into this session. I will begin with
network access services. The first network
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access service that I'm going to discuss is
actually a piece of hardware, the network
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interface controller or Nic, it can also be
called the network interface card. The Nic
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is how a device connects to a network. The
network interface controller works at two
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layers of the OSI model at layer two which
is the data link layer. It provides the functional
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means of network communication by determining
which networking protocols will be used as
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in a Nic that will provide Ethernet communication
or Nic that will provide Point to Point protocol.
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It also provides the local network node address
through its burned in physical media access
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control address at layer one the physical
layer, the network interface controller determines
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how the network data traffic will be converted
a bit at a time into an electrical signal
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that can traverse the network media being
used, ie it provides the connection to the
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network. Most modern computers come with at
least one built in Ethernet Nic routers and
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other network devices may use separate modules
that can be inserted into the device to provide
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the proper network interface controller for
the type of media they're connecting to in
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the networking protocols that are being used.
Another network access service is radius remote,
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authentic dial in user service radius is a
remote access service that is used to authenticate
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remote users and grant them access to authorized
network resources. It is a popular triple
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A protocol that's authentication, authorization
and accounting protocol. It's used to help
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ensure that only authenticated end users are
using the network resources they are authorized
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to use. The accounting services of radius
are very robust. The only drawback to radius
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is only the requesters the end users password
is encrypted. Everything else gets sent in
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the clear terminal access controller access
control system plus or TAC x plus terminal
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access controller access control system plus
point what a mouthful, it sure is easier to
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say. TAC x plus is a remote access service
that is used with authenticate remote devices
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and grant them access to authorized network
resources. It is also a popular triple A protocol
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used to help ensure that only authenticated
remote network devices are using the network
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resources that they are authorized to use.
With TAC x plus the accounting features are
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not as robust as those found in radius. But
all network transmissions between devices
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are encrypted with TAC x plus, let's move
on to other services and applications. First
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up is our AAS Remote Access Services. Now,
RS is not a protocol, but a roadmap. Rs is
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a description of the combination of software
and hardware required for remote access connection.
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A client requests access from an RS server,
which either grants or rejects that access.
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Then we have web services, creating a means
of cross communication. Web Services provides
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the means for communication between software
packages or disparate platforms. It's usually
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achieved by translating the communication
into an XML format, or Extensible Markup Language
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format. It is becoming more popular as systems
diverged. Last up is unified voice services.
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This is creating a better voice communication
system. It's a description of the combination
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of software and hardware required to integrate
voice communication channels into a network
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as in Voice over IP. That concludes this session
on networking services and applications. Part
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Two. I began by talking about network access
services. And I concluded with other services
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and applications. Hello, I'm Brian ferrill.
And welcome to pace eyeties session on DHCP
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in the network. Today, we're going to be talking
about static versus dynamic IP addressing.
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Then we're going to move on to how DHCP works.
And then we will conclude with components
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and processes of DHCP. And with that, let's
go ahead and begin this session. And of course,
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we begin by talking about static versus dynamic
IP addresses. So how does a computer know
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what its IP configuration is? Well, more than
likely a computer received its IP configuration
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from a Dynamic Host Configuration Protocol
server. Not only did the server give the PC
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an IP address, but it also told the PC where
the default gateway was, and more than likely
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how to find a DNS server, a computer will
receive its IP configuration in one of two
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ways. Either statically, which means manually
set or dynamically, which means through a
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service like DHCP static IP address assignment
works fine for very small and stable networks,
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but quickly becomes unwieldly and error prone
as the network grows and more nodes come on
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to the network. So let's talk a little bit
more about static IP addresses. The administrator
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assigned An IP number and subnet mask to each
host in the network, whether it be a PC, router
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or some other piece of electronic equipment.
Each network interface that is going to be
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available to connect to the network requires
this information. The administrator also assigns
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a default gateway location and DNS server
location to each host in the network. Now
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these settings are required if access to outside
networks is going to be allowed, that would
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be through the default gateway. And if human
friendly naming conventions are going to be
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allowed, and that way, you can more easily
find network resources, and that would be
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through a DNS server. Now each time a change
is made, as in a new default gateway is established,
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each IP configuration on each host must be
updated. That's why it becomes rather cumbersome
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and complicated as the network grows. Now
with dynamic IP addressing the administrator
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configures, a DHCP server to handle the assignment
process, which actually automates the process
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and eases management. The DHCP server listens
on a specific port for IP information requests.
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Once it receives a request, the DHCP server
responds with the required information. Now
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let's move on to how DHCP works. Here is the
typical DHCP process. Upon boot up a PC that
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is configured to request an IP configuration
sends a DHCP discovery packet. Now the discovery
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packet is sent to the broadcast address 255255255255
on UDP port 67. The DHCP server is listening
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to that port. It's listening for that discovery
packet. When the DHCP server receives the
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discovery packet, it responds with an offer
packet, basically saying hey, I'm here to
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help. Now the offer packet is sent back to
the MAC address of the computer requesting
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help, and it's sent on port 68. Once the computer
receives that offer packet from the DHCP server,
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if it's going to use that DHCP server, it
returns a request packet. That means it's
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requesting the proper IP configuration from
that specific DHCP server. Once the DHCP server
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receives the request packet, it sends back
an acknowledgment packet. Now this acknowledgement
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packet contains all of the required IP configuration
information. Once the PC receives the acknowledgment
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packet, the PC changes its IP configuration
to reflect the information that it received
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from the DHCP server. And that's the typical
DHCP process in a nutshell. Now let's talk
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about components and the process of DHCP.
We're going to begin by talking about the
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port's use. Now, I already mentioned this
once, but I'm going to mention it again because
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you need to know this. The PC sends its discovery
packet out on the broadcast address 255255255255
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on port 67. That's UDP port 67. When the DHCP
server responds, it responds to the PCs MAC
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address, Media Access Control address on UDP
port 68. That's important. Remember the PC
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uses UDP port 67. The DHCP server responds
on UDP port 68. Then there's the address scope.
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The address scope is the IP address range
that the administrator configures on the DHCP
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server. It is the range of addresses that
the DHCP server can hand out to individual
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nodes. There's also what are called address
reservations. Now these are administrator
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configured reserved IP addresses. The administrator
reserves specific IP addresses to be handed
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out to specific MAC addresses. Now these are
used for devices that should always have the
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same IP address. As in servers and routers.
If you did Do that there is the possibility
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that your default gateways IP address might
change. Now the reason we use address reservation
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is this allows these addresses to be changed
from a central location, instead of having
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to log into each device and change the IP
configuration separately. Now part of the
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DHCP process are what are called leases. The
DHCP server hands out that IP configuration
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information, but it sets a time limit for
how long that IP configuration is good. This
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is called the lease. So the parameters are
only good for a specified amount of time.
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Now the administrator can configure how long
the leases are, there are also options that
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the administrator can configure. The first
one that's pretty obvious is the default gateway
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location. There's also the DNS server address,
and the administrator can configure more than
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one DNS server location. And administrator
can also configure an option for the PC to
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synchronize with a time server. So the administrator
can configure a time server address. There
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are many more additional options, but those
are the big three that you should remember.
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Now when a PC boots up, it does have a preferred
IP address, that would be the IP address that
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it had the last time it booted up. Now he
can request that same IP configuration from
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the DHCP server. Now the administrator can
configure the DHCP server to either honor
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that preference or to ignore it. Now under
the right circumstances, a DHCP server isn't
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required to reside on the local network segment.
Now as a general rule, broadcast transmissions
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cannot pass through a router. But if there's
not a DHCP server on the local network segment,
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the router can be configured to be a DHCP
relay. When a DHCP relay, also called an IP
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helper receives a discovery packet from a
node, it will forward that packet to the network
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segment on which the DHCP server resides.
This allows for there to be fewer configured
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DHCP servers in any given network, reducing
the amount of maintenance that an administrator
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needs to perform. Now that concludes this
session on DHCP in the network, we started
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with static versus dynamic IP addressing.
And then we moved on to how DHCP works. And
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we concluded with components and processes
of DHCP. Hello, I'm Brian ferrill, and welcome
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to pace it session on the introduction to
the DNS service. Today we're going to be talking
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about DNS servers, DNS records, and we will
conclude with a brief discussion on dynamic
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DNS. And with that, let's go ahead and begin
this session. We're going to begin this session
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with a talk about DNS servers. Now DNS is
the process that maps human friendly names
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as in www.google.com, to their appropriate
IP addresses. Without DNS we would have to
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memorize all of the IP addresses that we wished
to visit. Now, DNS stands for Domain Name
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System, and it's very structured in nature.
If the local DNS server apparatus doesn't
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contain the needed record, it sends the request
up the DNS chain until the positive response
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is received back. Now this positive response
gets passed back down to the original requester.
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Now DNS does require that an F q dn fully
qualified domain name is used in order for
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it to function properly known Fq dn is the
www.google.com it's that naming convention
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right there. The www is the specific service
that's being requested. The Google portion
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is the local domain that contains the specific
service. And the calm is the top level that
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contains the Google that contains the specific
service that is an F q dn. Now that we've
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got that covered, let's talk about the different
levels of DNS servers. First off, there can
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be a local DNS server. This is the server
on the local network that contains the hosts
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file that map's all of the Fq DNS to their
specific IP addresses in the local sub domain,
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it may be present or it may not be present.
Then there are top level domain servers, the
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TLD server. Now, these are the servers that
contain the records for the top level domains,
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examples of top level domains are.com.org
dotnet.edu, so on and so forth. Now, each
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of these servers contains all of their information
for their respective domains kind of in what
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do I mean by kind of, well, the TLD servers
do delegate down to second level servers,
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their information, they do that to ease the
load so that the TLD server is not overloaded.
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But the TLD server is the server that is responsible
for maintaining the record. Then there's the
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root server. This is the server that contains
all of the records for the TLD servers. So
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if you're looking for a TLD, that is kind
of unknown, you will actually go to the root
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server, which will then pass you on to the
appropriate TLD. Then there are authoritative
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servers and non authoritative servers. And
authoritative DNS server is one that responds
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to a request. And that authoritative server
has been specifically configured to contain
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the requested information. an authoritative
response comes from a DNS server that actually
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holds the original record. So an authoritative
response comes from the name server that's
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been specifically configured to contain that
record, then there are non authoritative DNS
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servers. Now a non authoritative DNS server
is one that responds to to a request with
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DNS information that it received from another
DNS server. A non authoritative response is
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not a response from the official name server
for the domain. Instead, it is a second or
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third hand response that's given back to the
requester. In most cases, when we send a DNS
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request, we get a non authoritative response
back. Now let's move on to the various DNS
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record types. The first record that we're
going to talk about is the a record. Now the
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a record maps host names are Fq DNS to their
respective ipv4 addresses. closely associated
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with the a record is the a record or quadruple
a record this maps that Fq dn to its respective
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ipv6 address. Then there's the C name record.
Now, this maps a canonical name or alias to
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a hostname. What that means is that you can
have edcc.edu be the same as EDC dot o r g
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without having to maintain two sites, the
EDC c dot o r g can be the canonical name
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for EDC c.edu. This works in part because
of the pointer record the PTR record. It's
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a pointer record that points out to DNS that
there is a canonical name. And finally, we
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have the MS record. Now, this record maps
to the email server that is specified for
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a specific domain. It is the record that determines
how email travels from sender to recipient.
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And now let's move on to dynamic DNS. Now
dynamic DNS or DNS permits lightweight in
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immediate updates to a local DNS database.
This is very useful for when the Fq dn or
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hostname remains the same, but the IP address
is able to change on a regular basis. Dynamic
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DNS is implemented as an additional service
to DNS and it's implemented through DD ns
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updating. Now this is a method of updating
traditional names. without the intervention
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of an administrator, so there's no manual
editing or inputting of the configuration
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files required. A ddns provider supplies software
that will monitor the IP address of the reference
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system. Once the IP address changes, the software
sends an update to the proper DNS server.
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DNS is useful for when access is needed to
a domain whose IP address is being supplied
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dynamically by an ISP or internet service
provider. That way the IP address can change
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But people can still get to the service that
they're looking for. Now, that concludes this
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session on the introduction to the DNS service.
We talked about DNS servers, we moved on to
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DNS records. And then we concluded with a
very brief discussion about dynamic DNS. Hello,
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I'm Brian ferrill, and welcome to pace it
session introducing network address translation.
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Today, we're going to be talking about the
purpose of network address translation. And
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then we're going to discuss how network address
translation works. And with that, let's go
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ahead and begin this discussion. Of course,
we're going to begin by talking about the
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purpose of network address translation. network
address translation, or Nat solves a very
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serious problem of how to route non routable
IP addresses. As a partial effort to conserve
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the ipv4 address space, the private ipv4 addressing
spaces were developed, these address spaces
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were removed from the public ipv4 address
space and made non routable across public
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ipv4 networks. And this led to the problem
being non routable prevents that private ipv4
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address from communicating with remote public
networks. NAT very simply solves this problem.
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A router with Nat enabled will translate a
private IP address into a routable public
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IP address. When the response returns to the
router, it passes the response back to the
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device that requested it. So now that we've
covered the purpose, let's talk about how
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network address translation works. In First
off, we get to talk about the fact that there
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are two categories of Nat. First up is static
Nat. With static Nat each private IP address
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is assigned to a specific routable public
IP address this relationship is kept and maintained
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by the NAT enabled router. When a device needs
access outside of the local network. The router
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translates the local IP address to the assigned
public IP address. And when the response comes
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back, the router will translate the public
IP address back into a local one. Static Nat
386
00:48:32,039 --> 00:48:40,670
is not flexible in leads to some scalability
issues. An individual routable IP address
387
00:48:40,670 --> 00:48:46,950
must be kept for every device that requires
access outside of the local network. So as
388
00:48:46,950 --> 00:48:53,430
the network grows, you need to increase the
amount of public IP addresses that are under
389
00:48:53,430 --> 00:49:00,410
your control. That gets kind of expensive
and kind of complicated. They developed dynamic
390
00:49:00,410 --> 00:49:09,099
Nat to resolve some of that issue. With dynamic
Nat the NAT enabled router dynamically assigns
391
00:49:09,099 --> 00:49:17,990
a routable IP address to devices from a pool
of available IP addresses. When a device needs
392
00:49:17,990 --> 00:49:24,049
access outside of the local network. The router
performs the NAT function only the public
393
00:49:24,049 --> 00:49:32,130
IP address comes from a reusable pool of public
IP addresses. That private IP address is assigned
394
00:49:32,130 --> 00:49:38,901
the public IP address from the pool and once
outside accesses stop the routable IP address
395
00:49:38,901 --> 00:49:45,640
goes back into the pool to be reused. As initially
designed dynamic Nat was more flexible than
396
00:49:45,640 --> 00:49:52,150
static Nat, but it still led to some scalability
issues. As more network traffic required access
397
00:49:52,150 --> 00:49:59,930
to outside networks. The pool of available
public IP addresses needs to increase or outside
398
00:49:59,930 --> 00:50:07,720
Access cannot be achieved. But thankfully,
there is a solution to this. And that solution
399
00:50:07,720 --> 00:50:16,319
is called port address translation, or in
Cisco terms, that would be net with Pat. Pat
400
00:50:16,319 --> 00:50:22,250
is a type of dynamic Nat that was developed
to increase the scalability of network address
401
00:50:22,250 --> 00:50:29,460
translation. When a local network device requires
access to a public network, the net enabled
402
00:50:29,460 --> 00:50:36,269
router dynamically assigns the public IP address
to the device. With the addition of dynamically
403
00:50:36,269 --> 00:50:43,759
assigning a port number to the end of the
public IP address. The router tracks the IP
404
00:50:43,759 --> 00:50:49,680
addresses important numbers to ensure that
network traffic is routed to and from the
405
00:50:49,680 --> 00:50:56,500
proper devices. Pat still requires a pool
of public IP addresses. But the pool may only
406
00:50:56,500 --> 00:51:04,240
contain one public IP address, or it may contain
several for a large private network. This
407
00:51:04,240 --> 00:51:10,731
is the preferred method of implementing network
address translation for two reasons. First
408
00:51:10,731 --> 00:51:17,000
off, there's less public IP addresses that
are required. And it makes it easier for an
409
00:51:17,000 --> 00:51:25,049
administrator to maintain. Now let's talk
about Nat terminology, specifically about
410
00:51:25,049 --> 00:51:31,210
the types of addresses. And we begin with
the inside a local address, which is a private
411
00:51:31,210 --> 00:51:39,349
IP address on the local network. It is the
private IP address assigned to a specific
412
00:51:39,349 --> 00:51:47,440
device. Then there's the inside global address
a public address referencing an inside device.
413
00:51:47,440 --> 00:51:54,089
The inside global address is the public IP
address assigned to the inside device by the
414
00:51:54,089 --> 00:52:01,460
NAT enabled router allowing access outside
of the network. Then there's the outside global
415
00:52:01,460 --> 00:52:10,130
address, which is a public IP address referencing
an outside device. It is the public IP address
416
00:52:10,130 --> 00:52:16,900
assigned to a device outside of the local
network. Then there's the outside local address,
417
00:52:16,900 --> 00:52:24,509
which is the private IP address assigned to
an outside device. This is the private IP
418
00:52:24,509 --> 00:52:31,339
address assigned to the outside device by
the NAT enabled router on the interior of
419
00:52:31,339 --> 00:52:37,809
the local network so that the inside device
can communicate correctly with the outside
420
00:52:37,809 --> 00:52:45,560
device. Now that concludes this session on
introducing network address translation. We
421
00:52:45,560 --> 00:52:51,700
talked about the purpose of network address
translation. And then we talked about how
422
00:52:51,700 --> 00:53:02,579
network address translation works. Good day.
I'm Brian ferrill. And welcome to pace eyeties
423
00:53:02,579 --> 00:53:08,750
session on wind technologies part one. Today
I'm going to be talking about the public switched
424
00:53:08,750 --> 00:53:16,210
telephone network. Then I'm going to move
on to broadband cable. And I'm going to conclude
425
00:53:16,210 --> 00:53:23,569
with a brief section on fiber optics. And
with that, let's go ahead and begin this session.
426
00:53:23,569 --> 00:53:29,509
Of course, we begin with the public switched
telephone network. Before I begin with the
427
00:53:29,509 --> 00:53:36,390
public switched telephone network, let's talk
about what makes a win a win as opposed to
428
00:53:36,390 --> 00:53:43,940
a LAN. Well, as a general rule, if you own
and control the line that the data is using
429
00:53:43,940 --> 00:53:52,059
to get from one place to another, you are
not using a wide area network or when technology.
430
00:53:52,059 --> 00:53:57,530
On the other hand, if you are using a form
of transmission that you don't own, as in
431
00:53:57,530 --> 00:54:03,849
you're leasing a line or you're paying for
the use of it, then you are likely using when
432
00:54:03,849 --> 00:54:11,440
technology. One of the most common physical
infrastructures used in wind technology is
433
00:54:11,440 --> 00:54:19,210
the public switched telephone network, the
PSTN due to its widespread availability, just
434
00:54:19,210 --> 00:54:25,880
about everybody has a telephone line being
run to their house or to their building. An
435
00:54:25,880 --> 00:54:33,289
older technology but still somewhat valid
today for when technology is dial up. No dial
436
00:54:33,289 --> 00:54:41,529
up utilizes the PSTN to transmit network traffic
as an analog signal. dial up does require
437
00:54:41,529 --> 00:54:49,299
an analog modem to format the network traffic
correctly so it can be transmitted. Your maximum
438
00:54:49,299 --> 00:54:57,170
theoretical speed on dial up is 56 kilobits
per second. It's not very fast. Then there's
439
00:54:57,170 --> 00:55:06,249
ISDN integrated service. Digital Network ISDN
is a digital point to point when technology
440
00:55:06,249 --> 00:55:13,340
that utilizes the PSTN. It's a completely
digital service, it requires the use of a
441
00:55:13,340 --> 00:55:20,779
terminal adapter or ta to make the connection
to the end nodes. This ta is often called
442
00:55:20,779 --> 00:55:28,509
a digital modem, but it's not it's a terminal
adapter ISDN can use a primary rate interface
443
00:55:28,509 --> 00:55:39,430
or pri. Now the PRI is composed of 2364 kilobit
per second B channels and once 64 kilobit
444
00:55:39,430 --> 00:55:47,119
per second D channel that D channel is used
for call setup in link management. A pri can
445
00:55:47,119 --> 00:55:56,450
achieve 1.544 megabits per second speed, and
that is commonly referred to as a T one leased
446
00:55:56,450 --> 00:56:05,480
line. The most commonly implemented form of
an ISDN though is the Bri the basic rate interface,
447
00:56:05,480 --> 00:56:13,559
it uses only two B channels and one D channel,
and the Bri can achieve speeds of up to 128
448
00:56:13,559 --> 00:56:22,950
kilobits per second. Now ISDN is not as capable
as a digital subscriber line or DSL, but it
449
00:56:22,950 --> 00:56:30,099
can often be implemented where DSL cannot
be installed. Speaking about DSL, let's move
450
00:56:30,099 --> 00:56:40,460
on to it. xx DSL is the term for generic DSL.
DSL is a digital wind technology that utilizes
451
00:56:40,460 --> 00:56:49,250
the PSTN DSL does require the use of a digital
modem. It uses a dedicated digital line between
452
00:56:49,250 --> 00:56:56,890
the endpoint in a class five central office
or CEO. Now in order for the most basic forms
453
00:56:56,890 --> 00:57:05,880
of DSL to be installed, you have to be within
18,000 feet of the CEO. DSL is capable of
454
00:57:05,880 --> 00:57:12,680
carrying voice and data. When it does carry
both filters are put in place in order for
455
00:57:12,680 --> 00:57:19,150
the voice signal to come through without any
interference. Now let's move on to the different
456
00:57:19,150 --> 00:57:29,329
types of DSL. In First up is symmetric DSL
or sdsl. symmetric DSL is synchronous in nature.
457
00:57:29,329 --> 00:57:37,270
That means that the upload and download speeds
are the same as DSL does not carry voice communication.
458
00:57:37,270 --> 00:57:43,440
So if you need voice service, an additional
line is going to be needed. As DSL is used
459
00:57:43,440 --> 00:57:50,059
by businesses that don't quite need the performance
of a T one leased line, but they do require
460
00:57:50,059 --> 00:57:58,270
the symmetrical upload and download speeds.
more common than sdsl is ADSL or asymmetric
461
00:57:58,270 --> 00:58:05,619
DSL, it's asynchronous in nature. That means
that the upload speed is slower than the download
462
00:58:05,619 --> 00:58:15,090
speed. ADSL can carry data and voice common
upload speeds for ADSL are 768 kilobits per
463
00:58:15,090 --> 00:58:23,220
second, with download speeds of up to nine
megabits per second. It is the most common
464
00:58:23,220 --> 00:58:30,191
implementation of DSL, in the small office
home office environment. Last up for DSL is
465
00:58:30,191 --> 00:58:39,079
VDSL are very high bitrate DSL, it's asynchronous
in nature as well. It's used when high quality
466
00:58:39,079 --> 00:58:47,060
video in Voice over IP is necessary. VDSL
is commonly limited to download speeds of
467
00:58:47,060 --> 00:58:54,300
52 megabits per second with an upload speed
of 12 megabits per second. That's a whole
468
00:58:54,300 --> 00:59:04,210
lot faster than ADSL. But VDSL is only possible
when you're located within 4000 feet of a
469
00:59:04,210 --> 00:59:09,680
central office. There is an exception to what
I just told you though, the current standards
470
00:59:09,680 --> 00:59:18,089
do allow for up to 100 megabits per second
speed over the PSTN using VDSL. But in order
471
00:59:18,089 --> 00:59:26,710
to achieve that, you must be within 300 meters
of the central office. Now that the PSTN is
472
00:59:26,710 --> 00:59:35,799
out of the way, let's move on to broadband
cable. Broadband cable is coaxial cable networking.
473
00:59:35,799 --> 00:59:42,421
It's a broadband connection to a location
delivered by the cable company. Broadband
474
00:59:42,421 --> 00:59:49,000
cable can deliver voice data and television
all through the same connection. And the way
475
00:59:49,000 --> 00:59:55,259
it works is the digital signal is delivered
to the head and this is where all the cable
476
00:59:55,259 --> 01:00:02,460
signals are received. The signal is then processed
in format added and then transmitted to the
477
01:00:02,460 --> 01:00:09,230
distribution network. The distribution network
is a smaller service area served by the cable
478
01:00:09,230 --> 01:00:16,289
company. The distribution network architecture
can be composed of fiber optic cabling, or
479
01:00:16,289 --> 01:00:25,109
coaxial cabling, and or a hybrid fiber coaxial
cabling or HFC. Unlike DSL, the bandwidth
480
01:00:25,109 --> 01:00:30,650
of the distribution network is shared by all
of those who connect to it. This can lead
481
01:00:30,650 --> 01:00:37,650
to increase latency in congestion during busy
times. The final distribution to the premise
482
01:00:37,650 --> 01:00:43,099
is usually through a coaxial cable. The other
thing that you need to know about broadband
483
01:00:43,099 --> 01:00:51,240
cable is that all cable modems and similar
devices must measure up to the ISP is required
484
01:00:51,240 --> 01:00:59,180
data over cable service interface specifications
or DOCSIS specification. If it doesn't measure
485
01:00:59,180 --> 01:01:06,369
up, you're not going to achieve the speeds
that you expect. Now let's conclude with fiber.
486
01:01:06,369 --> 01:01:13,559
Fiber Optic networking is using light to transmit
data and voice. This allows for more bandwidth
487
01:01:13,559 --> 01:01:20,490
over greater distances. Fiber Optic networking
is more expensive to install, but it's also
488
01:01:20,490 --> 01:01:26,160
less susceptible to line noise. The fiber
synchronous data transmission standard in
489
01:01:26,160 --> 01:01:34,210
the United States is called the synchronous
optical network or sonnet standard. The international
490
01:01:34,210 --> 01:01:42,869
standard is called the synchronous digital
hierarchy are SDH. Both sonet and SDH defined
491
01:01:42,869 --> 01:01:49,009
the base rates of transmission over fiber
optic cabling, which are known as optical
492
01:01:49,009 --> 01:01:56,880
carrier levels. Dense wavelength division
multiplexing is a method of multiplexing several
493
01:01:56,880 --> 01:02:05,569
optical carrier levels together, up to 32
of them into a single fiber optic cable, effectively
494
01:02:05,569 --> 01:02:14,700
increasing the bandwidth of that single optical
fiber. Instead of dw dm you could use CW dm,
495
01:02:14,700 --> 01:02:21,519
course wavelength division multiplexing. It's
similar to dw dm, but it only allows for up
496
01:02:21,519 --> 01:02:28,089
to eight channels on a single fiber. When
fiber optic is delivered to the premise, it's
497
01:02:28,089 --> 01:02:36,359
usually delivered over a passive optical network
or upon upon is a point to multipoint technology
498
01:02:36,359 --> 01:02:43,109
that uses a single optical fiber that used
to connect multiple locations to the internet.
499
01:02:43,109 --> 01:02:50,769
The passive optical network uses unpowered
optical splitters. Now that concludes this
500
01:02:50,769 --> 01:02:57,309
session on wind technologies. Part One, I
talked about the public switched telephone
501
01:02:57,309 --> 01:03:08,480
network. Then we moved on to broadband cable,
and I briefly ran through fiber optic networking.
502
01:03:08,480 --> 01:03:16,069
Good day, I'm Brian ferrill. And welcome to
pace I t's session on web technologies, part
503
01:03:16,069 --> 01:03:23,700
two. Today we're going to be discussing GSM
and CDMA when connections, then we're going
504
01:03:23,700 --> 01:03:31,049
to move on to why max when connections and
we're going to conclude with satellite wide
505
01:03:31,049 --> 01:03:36,920
area network connections. There's a fair amount
of information to cover. So let's go ahead
506
01:03:36,920 --> 01:03:44,489
and begin this session. And of course, I'm
going to begin with the GSM and CDMA wide
507
01:03:44,489 --> 01:03:52,759
area network connections. All cellular carriers
use one of two methods for connecting devices
508
01:03:52,759 --> 01:03:59,239
to their networks, and those methods are not
compatible. Currently in the United States,
509
01:03:59,239 --> 01:04:08,579
at&t and T Mobile use the global system for
mobile or GSM standard to connect their devices
510
01:04:08,579 --> 01:04:15,549
to their networks. Both sprint and Verizon
use code division multiple access, also known
511
01:04:15,549 --> 01:04:24,060
as cvma, as their method of connecting to
networks. In those two standards are not compatible.
512
01:04:24,060 --> 01:04:33,609
The majority of the rest of the world utilizes
GSM as the method for cellular network access.
513
01:04:33,609 --> 01:04:40,640
Let me speak briefly about cellular networking.
Cellular networking involves using the cellular
514
01:04:40,640 --> 01:04:46,579
phone system for more than just phone calls.
Cellular networking has been around for a
515
01:04:46,579 --> 01:04:52,519
while and it originally wasn't known as this,
but the first version of it is first G or
516
01:04:52,519 --> 01:04:59,400
one g cellular and it was only capable of
voice transmissions as improvements came along.
517
01:04:59,400 --> 01:05:06,269
We got to GE that is cellular with simple
data transmission capabilities, as in text
518
01:05:06,269 --> 01:05:12,750
messaging, 2g edge offered some basic cellular
networking connectivity and was a stopgap
519
01:05:12,750 --> 01:05:21,280
measure between 2g in third generation cellular.
3g cellular is the beginning of cellular win
520
01:05:21,280 --> 01:05:29,079
networking, it's giving way to 4g cellular,
which is still an emerging technology. 4g
521
01:05:29,079 --> 01:05:36,390
currently consists of both LTE and y max.
As a special mention, we need to talk about
522
01:05:36,390 --> 01:05:45,319
evolved high speed Packet Access, which is
HSPA. Plus, it was a stop gap between 3g and
523
01:05:45,319 --> 01:05:52,099
4g networking. It's still available today.
The current standard for HSPA plus allows
524
01:05:52,099 --> 01:05:59,700
for up to a maximum data rate of 84 megabits
per second. Now it's not quite as good as
525
01:05:59,700 --> 01:06:09,279
LTE, which is Long Term Evolution. LTE uses
an all IP based core with high data rates.
526
01:06:09,279 --> 01:06:17,069
Now LTE is compatible with both 3g ny Max,
the current standard for LTE allows for up
527
01:06:17,069 --> 01:06:24,599
to 300 megabits per second in download speeds,
and up to 75 megabits per second in upload
528
01:06:24,599 --> 01:06:33,509
speeds. Now let me introduce you to why max
when connections, why max stands for worldwide
529
01:06:33,509 --> 01:06:42,380
interoperability for microwave access. That's
a mouthful. That's why we say y max. y max
530
01:06:42,380 --> 01:06:50,480
was originally developed as a last mile alternative
to use when DSL or cable was not available.
531
01:06:50,480 --> 01:06:58,849
It can provide an alternative broadband connection
to a fixed location. It uses microwave transmissions
532
01:06:58,849 --> 01:07:05,789
as an over the air method to transmit voice
and data. It does require line of sight between
533
01:07:05,789 --> 01:07:13,950
relay stations, but why max can be used to
cover significant geographic distances. Also,
534
01:07:13,950 --> 01:07:20,210
many municipalities are exploring the use
of y max as a means of providing reasonably
535
01:07:20,210 --> 01:07:27,750
priced broadband to their citizens without
having to wire every household. y max is often
536
01:07:27,750 --> 01:07:35,069
considered to be a type of 4g technology,
because it is compatible with LTE networks.
537
01:07:35,069 --> 01:07:45,009
But why Max is not compatible with third generation
cellular networks. It is time for us to conclude
538
01:07:45,009 --> 01:07:52,660
with satellite when connections. Satellite
Wang connections are a type of microwave satellite
539
01:07:52,660 --> 01:07:58,710
networking. It uses microwave transmissions
as an over the air method of transmitting
540
01:07:58,710 --> 01:08:05,119
voice and data just like y mx, it can be an
effective means of extending networks into
541
01:08:05,119 --> 01:08:11,799
places that are hard to reach. It does use
microwave radio relay as the method of transmitting
542
01:08:11,799 --> 01:08:17,760
data through the atmosphere. Just like white
mat, it requires line of sight relay stations,
543
01:08:17,760 --> 01:08:24,570
but it can cover even more distances than
y max. Why is that? That's because it utilizes
544
01:08:24,570 --> 01:08:29,960
a satellite network. By the way, because of
the distances that satellite transmissions
545
01:08:29,960 --> 01:08:35,980
can cover. This can lead to latency problems,
think about it, the signals got to go from
546
01:08:35,980 --> 01:08:42,070
a terrestrial location, up to the satellite,
probably over to another satellite and then
547
01:08:42,070 --> 01:08:47,541
down to another terrestrial station. That's
a significant amount of distance. And there's
548
01:08:47,541 --> 01:08:52,890
going to be some lag. I just talked about
the communication satellite there also known
549
01:08:52,890 --> 01:09:00,070
as comsats. These do form part of the microwave
relay network. COMM sets can use a variety
550
01:09:00,070 --> 01:09:09,260
of orbits, including the millennia. geostationary
low polar or polar orbits. The low polar and
551
01:09:09,260 --> 01:09:17,180
polar orbits are used to boost microwave signals
before sending the signal back to Earth. Now
552
01:09:17,180 --> 01:09:25,780
that concludes this session on wind technologies
part two. I briefly talked about GSM and CDMA
553
01:09:25,780 --> 01:09:33,720
when connections, then I moved on to why max
win connections and then we concluded with
554
01:09:33,720 --> 01:09:43,640
satellite wind connections. Hello, I'm Brian
ferrill. And welcome to pace eyeties session
555
01:09:43,640 --> 01:09:50,650
on wind technologies part three. Today I'm
going to briefly discuss Metro Ethernet when
556
01:09:50,650 --> 01:09:56,310
connections. Then I'm going to move on to
leased line when connections and we're going
557
01:09:56,310 --> 01:10:04,120
to conclude with some common standards. With
that, let's go ahead and begin this session.
558
01:10:04,120 --> 01:10:11,200
Of course, I'm going to begin by discussing
Metro Ethernet when connections. A Metro Ethernet
559
01:10:11,200 --> 01:10:19,500
connection is when the service provider connects
to the customer's site through an RJ 45 connector.
560
01:10:19,500 --> 01:10:25,340
The customer will view that when connection
as an Ethernet connection while in reality
561
01:10:25,340 --> 01:10:31,780
the type of connection will be dependent upon
the level of service that has been purchased.
562
01:10:31,780 --> 01:10:38,480
The service provider may also use a variety
of different wide area network technologies
563
01:10:38,480 --> 01:10:45,650
behind the scenes, but the customer will always
view it as being an Ethernet connection. Metro
564
01:10:45,650 --> 01:10:54,620
Ethernet is commonly deployed as a wide area
network technology by municipalities at the
565
01:10:54,620 --> 01:11:03,070
Metropolitan Area Network or man level. As
in at the municipal level, it's time for us
566
01:11:03,070 --> 01:11:12,680
to discuss leased line when connections. A
leased line is a dedicated circuit or connection
567
01:11:12,680 --> 01:11:20,140
between two endpoints used for communication.
When we're talking about it. A leased line
568
01:11:20,140 --> 01:11:27,010
is usually a digital Point to Point connection.
A leased line can utilize either a plain old
569
01:11:27,010 --> 01:11:34,011
telephone service line, a Potts line on the
public switched telephone network, or it can
570
01:11:34,011 --> 01:11:41,840
be a fiber optic circuit provided by a telecommunications
company. leased lines tend to be more expensive
571
01:11:41,840 --> 01:11:47,330
for the customer, as the circuit can't be
utilized by any other entity. So the whole
572
01:11:47,330 --> 01:11:53,440
cost is borne by the customer because they're
the only ones who get to use it. Most often,
573
01:11:53,440 --> 01:12:00,410
the speed of a leased line is limited by what
the customer is willing to pay. There are
574
01:12:00,410 --> 01:12:06,700
some multiplexing technologies out there that
can be used to increase the amount of channels
575
01:12:06,700 --> 01:12:12,790
that are provided on the connection. One of
the leased line technologies that you need
576
01:12:12,790 --> 01:12:22,340
to know about is point to point protocol PPP.
It is a common data link layer or layer two
577
01:12:22,340 --> 01:12:30,030
protocol that's used with leased line networks,
PPP can simultaneously transmit multiple layer
578
01:12:30,030 --> 01:12:38,500
three protocols. It can transmit IP and IP
x and appletalk, all at the same time, through
579
01:12:38,500 --> 01:12:45,220
the use of control protocols, which are actually
specific to the layer three protocol that's
580
01:12:45,220 --> 01:12:53,450
being transmitted. PPP can include a feature
called multi link PPP, which allows for multiple
581
01:12:53,450 --> 01:13:00,090
physical interfaces to be bonded together
and act as a single logical interface. This
582
01:13:00,090 --> 01:13:07,800
effectively increases the available bandwidth
to that system. There are different types
583
01:13:07,800 --> 01:13:13,690
of leased line connections. In the United
States, Japan and South Korea, there are t
584
01:13:13,690 --> 01:13:21,320
carrier lines. Each t line is composed of
24 Digital Signal channels. These are often
585
01:13:21,320 --> 01:13:28,550
called digital signals, zero channels are
DSO channels, each channel is capable of carrying
586
01:13:28,550 --> 01:13:38,220
64 kilobits per second, the 24 dsos make up
what is called a DS one channel. In Europe,
587
01:13:38,220 --> 01:13:46,970
we have e carrier lines, each line is composed
of 30 Digital Signal channels. These are also
588
01:13:46,970 --> 01:13:54,921
called DSO channels, the 30 DSL channels also
make up what is called a DS one channel. When
589
01:13:54,921 --> 01:14:01,580
we're talking about fiber optic speeds, we
often talk about optical carrier lines, or
590
01:14:01,580 --> 01:14:09,940
OSI lines. The OSI data rates per channel
are established by both the sonnet and SDH
591
01:14:09,940 --> 01:14:16,120
networking standards. Sonnet is the United
States standard, and SDH is the international
592
01:14:16,120 --> 01:14:23,520
standards. Interestingly enough, the OSI rates
are the same across the two standards, it's
593
01:14:23,520 --> 01:14:30,760
possible to multiplex multiple channels into
the same fiber using different methods. The
594
01:14:30,760 --> 01:14:38,380
first method is dense wavelength division
multiplexing dw dm, it allows for up to 32
595
01:14:38,380 --> 01:14:44,990
separate channels on a single fiber cable,
or you could use coarse wavelength division
596
01:14:44,990 --> 01:14:51,220
multiplexing, which allows for up to eight
separate channels on a single fiber optic
597
01:14:51,220 --> 01:14:58,670
cable. Let's conclude with common standards.
The standards I'm going to be talking about
598
01:14:58,670 --> 01:15:07,391
are the speeds We begin with ti lines. A T
one is composed of 24 DSO channels, which
599
01:15:07,391 --> 01:15:15,550
are also known as a DS one, and it's capable
of achieving speeds of up to 1.544 megabits
600
01:15:15,550 --> 01:15:22,930
per second. If that's not fast enough for
you, you can lease a T three line. It's composed
601
01:15:22,930 --> 01:15:31,790
of 28 T one lines. Now a T three line is also
known as a DS three, and it can achieve speeds
602
01:15:31,790 --> 01:15:40,690
of up to 44.736 megabits per second. If you're
in Europe, you might lease an E one line,
603
01:15:40,690 --> 01:15:48,410
an E one line which is composed of 30 DSL
channels can achieve speeds of up to 2.048
604
01:15:48,410 --> 01:15:53,980
megabits per second. Just as with the United
States, if that's not fast enough for you,
605
01:15:53,980 --> 01:16:03,130
you can lease an E three line which is composed
of 16 e one lines, which gives you up to 34.368
606
01:16:03,130 --> 01:16:11,080
megabits per second speed. Well, if T one
is slower than an E one, a T three is faster
607
01:16:11,080 --> 01:16:18,990
than any three. For all c lines. We have the
OSI one, it's capable of 51 point 84 megabits
608
01:16:18,990 --> 01:16:27,990
per second in speed, then there is the OSI
three, which gives you up to 155.52 megabits
609
01:16:27,990 --> 01:16:34,260
per second speed. It's becoming more common
now to see OC twelves. With those you get
610
01:16:34,260 --> 01:16:43,040
up to 622.08 megabits per second. If you want
gigabit type speed, you might consider leasing
611
01:16:43,040 --> 01:16:52,280
an OC 48 that gives you up to 2.488 gigabits
per second in bandwidth. Currently at the
612
01:16:52,280 --> 01:17:01,720
top of the line is the OSI 192. That gives
you up to 9.953 gigabits per second speed.
613
01:17:01,720 --> 01:17:08,980
So essentially 10 gigabits per second worth
of bandwidth. Now that concludes this session
614
01:17:08,980 --> 01:17:15,670
on web technologies. Part Three, I briefly
discussed Metro Ethernet when connections,
615
01:17:15,670 --> 01:17:21,390
and then I went on to a discussion about leased
line Wang connections. And then I briefly
616
01:17:21,390 --> 01:17:31,490
mentioned some common standards. Hello, I'm
Brian ferrill, and welcome to pace it session
617
01:17:31,490 --> 01:17:38,080
on web technologies Part Four. Today I'm going
to be discussing the difference between circuit
618
01:17:38,080 --> 01:17:44,540
switched and packet switch networks. Then
I'm going to move on to a discussion comparing
619
01:17:44,540 --> 01:17:51,460
frame relay versus Asynchronous Transfer Mode.
And then we're going to conclude with multi
620
01:17:51,460 --> 01:17:57,030
protocol Label Switching. There's a whole
lot of ground to cover, not a whole lot of
621
01:17:57,030 --> 01:18:03,480
time. Let's go ahead and begin the session.
Let's begin this session by talking about
622
01:18:03,480 --> 01:18:11,190
circuit switched and packet switched networks.
Circuit switch networks have a dedicated circuit
623
01:18:11,190 --> 01:18:17,440
between two endpoints that is used for communication.
While set up the circuit can only be used
624
01:18:17,440 --> 01:18:24,200
for communication between those ends. Circuit
switch networks are most common in networks
625
01:18:24,200 --> 01:18:30,200
with leased line communication channels. They're
best used when there needs to be a fair amount
626
01:18:30,200 --> 01:18:36,670
of continuous data traffic between the two
endpoints. In what circuit switch networks,
627
01:18:36,670 --> 01:18:43,900
there is only one path for the data to take.
On the other hand, in packet switch networks
628
01:18:43,900 --> 01:18:49,650
data is broken up into smaller chunks and
move through the network only to be reassembled
629
01:18:49,650 --> 01:18:56,250
at the other end. The data is routed using
the destination address and the data may take
630
01:18:56,250 --> 01:19:02,370
different paths through the network that it's
traveling through. As a general rule, packet
631
01:19:02,370 --> 01:19:09,240
switch networks are less expensive to maintain.
Why? Because the user doesn't have to maintain
632
01:19:09,240 --> 01:19:16,980
a dedicated circuit 24 seven, they're only
paying for what they're using. Now let's talk
633
01:19:16,980 --> 01:19:23,410
about the differences between frame relay
and Asynchronous Transfer Mode. Frame Relay
634
01:19:23,410 --> 01:19:29,831
is a wind technology in which variable length
packets are switched across the network. Frame
635
01:19:29,831 --> 01:19:37,110
Relay is less expensive than leased lines.
But frame relay can be made to look like a
636
01:19:37,110 --> 01:19:45,000
leased line through virtual circuits or VCs.
A frame relay network will track a VC using
637
01:19:45,000 --> 01:19:52,400
a Data Link connection identifier to identify
the end of the VC. There are two terms associated
638
01:19:52,400 --> 01:19:58,010
with frame relay that you should be aware
of. The first is access rate. That is the
639
01:19:58,010 --> 01:20:05,640
maximum speed of Frame Relay interface. The
other term is the committed information rate,
640
01:20:05,640 --> 01:20:12,330
the cir, that's the guaranteed bandwidth that
a customer receives. So that's the minimum
641
01:20:12,330 --> 01:20:19,520
speed of that frame relay network, the access
rate may be higher, but the customer is always
642
01:20:19,520 --> 01:20:25,061
guaranteed the committed information rate.
Now let's talk about Asynchronous Transfer
643
01:20:25,061 --> 01:20:33,400
Mode, also known as ATM. ATM is a wind technology
in which fixed length cells are switched across
644
01:20:33,400 --> 01:20:42,700
the network. These cells are always 53 bytes
long. ATM can handle real time voice and video,
645
01:20:42,700 --> 01:20:49,950
because it's very fast, but it has poor bandwidth
utilization. The small cell size reduces the
646
01:20:49,950 --> 01:20:57,460
efficiency of the technology. But ATM is very
fast even if it is inefficient. Common speeds
647
01:20:57,460 --> 01:21:08,440
on an ATM network are 51 point 84 megabits
per second and 155.52 megabits per second.
648
01:21:08,440 --> 01:21:15,110
Let's conclude with multiprotocol Label Switching.
The acronym for multi protocol Label Switching
649
01:21:15,110 --> 01:21:24,120
is MPLS. MPLS is a topology that's growing
in popularity. Why? Because it's scalable.
650
01:21:24,120 --> 01:21:32,070
Also it is protocol independent MPLS can be
used to replace both frame relay switching
651
01:21:32,070 --> 01:21:40,140
and ATM switching. It can be used to packet
switch both frame relay and ATM network traffic.
652
01:21:40,140 --> 01:21:48,150
This allows MPLS to be used with both frame
relay and ATM technologies. MPLS is often
653
01:21:48,150 --> 01:21:55,810
used to improve quality of service and flow
of network traffic. It uses a label edge router
654
01:21:55,810 --> 01:22:02,450
to add MPLS labels to incoming packets if
they don't have them. The label edge router
655
01:22:02,450 --> 01:22:10,900
then passes those packets on to a Label Switching
router or LSR router. The LSR forwards those
656
01:22:10,900 --> 01:22:18,050
packets based on their MPLS labels to their
final destination. Now that concludes this
657
01:22:18,050 --> 01:22:24,600
session on when technologies Part Four, I
talked about the differences between a circuit
658
01:22:24,600 --> 01:22:30,880
switched and packet switch network. Then we
moved on to frame relay versus Asynchronous
659
01:22:30,880 --> 01:22:37,480
Transfer Mode. And we concluded with the brief
discussion on multi protocol Label Switching.
660
01:22:37,480 --> 01:22:47,731
Hello, I'm Brian ferrill. And welcome to pace
it session on network cabling part one. Today
661
01:22:47,731 --> 01:22:52,340
we're going to be talking about twisted pair
network cabling. Then we're going to talk
662
01:22:52,340 --> 01:22:58,100
about twisted pair network connectors. And
then we will conclude with categories of twisted
663
01:22:58,100 --> 01:23:03,190
pair. I have a whole lot of information to
cover and I need to get through this quickly.
664
01:23:03,190 --> 01:23:08,970
So let's go ahead and begin the session. And
we'll begin by talking about twisted pair
665
01:23:08,970 --> 01:23:15,660
network cabling. Most people are familiar
with twisted pair cables because they are
666
01:23:15,660 --> 01:23:20,740
the standard in the modern LAN they are what
you see most often when you're looking at
667
01:23:20,740 --> 01:23:27,020
network cable. twisted pair cables are composed
of four pairs of wires contained within an
668
01:23:27,020 --> 01:23:34,560
insulating sheath. Each pair of wires is twisted
together to reduce electromagnetic interference,
669
01:23:34,560 --> 01:23:41,710
which is called EMI. The twist rates differ
between the pairs to reduce cross talk between
670
01:23:41,710 --> 01:23:49,260
the pairs which is a type of EMI. The colors
of the pairs of wires are always white, orange,
671
01:23:49,260 --> 01:23:56,520
orange, white, blue, blue, white, green, green,
and white brown, brown. Twisted pair network
672
01:23:56,520 --> 01:24:05,530
cabling comes in either unshielded or shielded
twisted pair that would be UTP or STP. The
673
01:24:05,530 --> 01:24:11,000
difference is that STP has an additional shield
that is either wrapped around each pair of
674
01:24:11,000 --> 01:24:17,280
wires are around all four pairs of wires.
That shielding reduces the opportunity for
675
01:24:17,280 --> 01:24:23,691
EMI or cross talk, but it is more expensive
and a little harder to work with. Because
676
01:24:23,691 --> 01:24:31,240
it's not as flexible UTP or unshielded twisted
pair is deployed in the network much more
677
01:24:31,240 --> 01:24:39,950
often than STP. There are also plenum and
non plenum types of twisted pair. Most twisted
678
01:24:39,950 --> 01:24:47,400
pair cabling is non plenum grade, but building
codes often call for plenum grade cable to
679
01:24:47,400 --> 01:24:53,760
be run in plenum spaces. No a plenum space
is that area that is designed to assist in
680
01:24:53,760 --> 01:25:01,600
the air flow of a building for HVDC purposes
and most often the planet Is that space between
681
01:25:01,600 --> 01:25:07,560
the false ceiling and the actual ceiling.
plenum cable is jacketed in either a fire
682
01:25:07,560 --> 01:25:15,270
retardant cover or in a low smoke PVC jacket.
plenum cables often have a polymer or nylon
683
01:25:15,270 --> 01:25:20,400
strand woven into the cabling or into the
jacket to help take the weight of hanging
684
01:25:20,400 --> 01:25:26,770
cables. This reduces the chance for the cable
to stretch which can cause the pair or pairs
685
01:25:26,770 --> 01:25:33,080
of wires inside the jacket to break. Twisted
pair is usually either a straight through
686
01:25:33,080 --> 01:25:40,270
cable or a crossover cable, but it can also
be used to create a rollover or console cable.
687
01:25:40,270 --> 01:25:45,740
A straight through cable is used to connect
different types of devices together, as in
688
01:25:45,740 --> 01:25:52,000
a computer to a switch or switch to a router.
Well a crossover cable is used to connect
689
01:25:52,000 --> 01:25:59,290
similar devices together, as in a PC to a
PC or a switch to a switch the straight through
690
01:25:59,290 --> 01:26:05,430
in crossover cable use different pin outs
to achieve their connections. A rollover or
691
01:26:05,430 --> 01:26:12,130
console cable is often required to connect
to the console port on a switch or a router.
692
01:26:12,130 --> 01:26:18,550
It is quite common for one end of the rollover
cable to use an RJ 45 connector, while the
693
01:26:18,550 --> 01:26:26,540
other end utilizes an RS 232, also called
a DB nine connector. So now that I've mentioned
694
01:26:26,540 --> 01:26:32,540
those connectors, let's go on to twisted pair
network connectors. And we're going to begin
695
01:26:32,540 --> 01:26:38,040
with the rj 11. You don't see these very much
in what we think of as networking, but you
696
01:26:38,040 --> 01:26:46,150
do see them all the time. The rj 11 uses a
sixth position for a contact modular connector.
697
01:26:46,150 --> 01:26:52,960
That's a six p four c modular connector. It
can carry data or voice and it's common usage
698
01:26:52,960 --> 01:26:59,690
is voice communication, telephony, all of
your telephone jacks are our j elevens. Then
699
01:26:59,690 --> 01:27:05,290
there's the rj 45. This is the one that we
always think about when we think about networking
700
01:27:05,290 --> 01:27:12,530
with twisted pair of cabling. It uses an eight
position eight contact or eight p eight c
701
01:27:12,530 --> 01:27:19,750
modular connector. It can carry data or voice
and it's common usage is data networking,
702
01:27:19,750 --> 01:27:26,970
Ethernet, then there's the rj 48 C, it also
uses an eight position eight contact modular
703
01:27:26,970 --> 01:27:33,570
connector eight p eight c just like the rj
45 is a matter of fact, it's often thought
704
01:27:33,570 --> 01:27:40,510
of as being an RJ 45. But it's used as the
terminating connector at the demark point
705
01:27:40,510 --> 01:27:46,660
for T one lines. And as I said just a moment
ago, it's often confused with the rj 45 but
706
01:27:46,660 --> 01:27:54,670
the active pins are different. Then we have
the UTP coupler, the unshielded twisted pair
707
01:27:54,670 --> 01:28:03,000
coupler. It's used to connect UTP cables back
to back and still maintain adherence to industry
708
01:28:03,000 --> 01:28:08,410
standards, you might still come across the
66 block being used for network connections,
709
01:28:08,410 --> 01:28:13,530
but probably not. It's a punch down block
that was initially developed to terminate
710
01:28:13,530 --> 01:28:20,390
in distributed telephone lines in an enterprise
network. So you might still see it for telephony,
711
01:28:20,390 --> 01:28:25,680
but it's getting a little bit harder to find
it. It was also used in slower speed networks
712
01:28:25,680 --> 01:28:31,250
as it can handle data traffic that's rated
for cat three cabling, much more likely you'll
713
01:28:31,250 --> 01:28:36,650
find a 110 block. Now this is a punch down
block that was developed to terminate and
714
01:28:36,650 --> 01:28:43,190
distribute twisted pair network cabling. It's
capable of handling the signaling requirements
715
01:28:43,190 --> 01:28:49,961
of the modern network. I mentioned the DB
nine or rs 232 connector earlier. Well here
716
01:28:49,961 --> 01:28:59,000
we go. It is a nine pin D sub miniature connector
developed for asynchronous serial communication
717
01:28:59,000 --> 01:29:06,240
between nodes. It was a common type of connector
between a computer and an external modem.
718
01:29:06,240 --> 01:29:12,970
And as I said earlier, it often makes up one
end of the rollover cable, you might come
719
01:29:12,970 --> 01:29:25,480
across the dbx 25 also known as an Ei a 232,
or rs 232 serial connector. It is a 25 pin
720
01:29:25,480 --> 01:29:32,630
D sub miniature connector developed for asynchronous
serial communication between nodes just like
721
01:29:32,630 --> 01:29:39,470
the DB nine only it was larger it to provided
a type of connection between a computer and
722
01:29:39,470 --> 01:29:46,780
an external analog modem. And it's even less
common than the DB nine. Now let's move on
723
01:29:46,780 --> 01:29:52,980
to categories of twisted pair. And we begin
with cat three cat three was rated for up
724
01:29:52,980 --> 01:29:59,840
to 10 megabits per second speed, that's 10
base t networking and it had a maximum delay
725
01:29:59,840 --> 01:30:07,410
distance of 100 meters. By the way, unless
I specify all twisted pair cabling has a max
726
01:30:07,410 --> 01:30:13,890
distance of 100 meters, that 10 megabits per
second wasn't quite fast enough. So then we
727
01:30:13,890 --> 01:30:22,060
got cat five cat five is rated for up to 100
megabits per second speed, that's 100 base
728
01:30:22,060 --> 01:30:28,870
t networking. And that still wasn't fast enough.
So they developed cat five E to cat five,
729
01:30:28,870 --> 01:30:38,321
he is rated for up to one gigabits per second,
that's 1000 base t. Now we have cat six, cat
730
01:30:38,321 --> 01:30:46,420
six is rated for up to 10 gigabits per second,
that's 10 Gigabit Ethernet, or 10 gb E. And
731
01:30:46,420 --> 01:30:54,020
with cat six, you can only get that 10 gigabits
per second over a max distance of 55 meters.
732
01:30:54,020 --> 01:30:59,260
For some reason they thought they needed to
go more distance than 55 meters. So they developed
733
01:30:59,260 --> 01:31:07,930
cat six a, it has the same speed readings
as cat six, but it has a max distance of 100
734
01:31:07,930 --> 01:31:14,700
meters and you can still achieve that 10 gigabits
per second networking. Now that concludes
735
01:31:14,700 --> 01:31:21,060
this session on network cabling part one.
I talked about twisted pair cabling. Then
736
01:31:21,060 --> 01:31:27,740
I talked about twisted pair network connectors,
and I concluded with the categories of twisted
737
01:31:27,740 --> 01:31:37,270
pair cabling. Hello, I'm Brian ferrill, and
welcome to pace eyeties session on network
738
01:31:37,270 --> 01:31:44,380
cabling part two. Today we're going to be
talking about coaxial cabling, and fiber optic
739
01:31:44,380 --> 01:31:50,420
cabling. There's a fair amount of ground to
cover so let's go ahead and begin this session.
740
01:31:50,420 --> 01:31:58,940
And of course we're going to begin by talking
about coaxial cabling. coaxial or co x cabling
741
01:31:58,940 --> 01:32:06,880
is one of the oldest Ethernet standards for
network cabling. It was standardized in 1973.
742
01:32:06,880 --> 01:32:12,670
It's been used for baseband carries just a
single digital signal and it has been used
743
01:32:12,670 --> 01:32:19,140
for broadband carrying multiple digital signals.
It is composed of a central conductor that
744
01:32:19,140 --> 01:32:25,690
is covered by an insulating layer, which is
covered by an outer mesh or foil layer, which
745
01:32:25,690 --> 01:32:32,420
is then finished off with an outer insulating
layer. That inner metal mesh layer helps to
746
01:32:32,420 --> 01:32:38,850
protect against electromagnetic interference
EMI, there are several different types of
747
01:32:38,850 --> 01:32:47,660
CO x cable. There is rG 58. It was used in
10 base two networking, it could span a maximum
748
01:32:47,660 --> 01:32:57,150
distance of 185 meters and had a 50 ohms impedance
value. It's no longer commonly found in the
749
01:32:57,150 --> 01:33:04,510
modern network. Then there's rG 59. It's commonly
used to provide a broadband connection between
750
01:33:04,510 --> 01:33:12,880
two devices over a short distance and it has
a 75 ohms impedance value. And it's only used
751
01:33:12,880 --> 01:33:21,170
for short distances because it leaks its signal
it can't span very far. Then we have RG six,
752
01:33:21,170 --> 01:33:28,190
which is used for cable TV or broadband. Now
the distance that RG six can span varies,
753
01:33:28,190 --> 01:33:35,110
but it still has a 75 ohms impedance value,
and it's commonly used to make the connection
754
01:33:35,110 --> 01:33:43,700
to a cable modem by the cable company. There
are two basic types of CO x cable connectors.
755
01:33:43,700 --> 01:33:50,610
There is the BNC also known as the bayonet
meal Councilman connector. You can also call
756
01:33:50,610 --> 01:33:57,650
it a bayonet connector. It is used with CO
x cabling, but is now considered obsolete.
757
01:33:57,650 --> 01:34:02,660
The connection from the cable to the device
was achieved through a spring loaded twist
758
01:34:02,660 --> 01:34:09,910
lock type of connector. A BNC coupler can
also be used to connect to coax cable segments
759
01:34:09,910 --> 01:34:17,570
back to back much more common is the F connector.
It's a threaded bayonet connector, and it's
760
01:34:17,570 --> 01:34:24,390
also used with CO x cable. An f connector
coupler can be used to connect to coax cable
761
01:34:24,390 --> 01:34:31,700
segments back to back. Now let's move on to
fiber optic cabling. So now let me describe
762
01:34:31,700 --> 01:34:37,970
fiber optic cabling. First off, it's relatively
expensive and harder to work with than with
763
01:34:37,970 --> 01:34:45,430
other types of network cabling. It's not as
common as other types either co x or twisted
764
01:34:45,430 --> 01:34:52,080
pair in the land environment. But it can resist
all forms of electromagnetic interference
765
01:34:52,080 --> 01:34:58,970
and it cannot be easily tapped into. That
means it's harder for people to ease drop
766
01:34:58,970 --> 01:35:07,500
on your network. missions. It also can cover
long distances at high speed. Fiber Optic
767
01:35:07,500 --> 01:35:13,170
cabling is designated by fiber type cladding
size. By the way, the cladding is what the
768
01:35:13,170 --> 01:35:19,620
light bounces down, and it's jacket size that
outer jacket that covers the cable. The size
769
01:35:19,620 --> 01:35:25,630
of the cladding and the size of the jacket
are listed in micrometres. Most applications
770
01:35:25,630 --> 01:35:32,700
of fiber optic cabling require that the cables
be run in pairs, one cable to send transmissions
771
01:35:32,700 --> 01:35:38,750
one cable to receive transmissions. The type
of connector used on fiber optic cabling can
772
01:35:38,750 --> 01:35:45,390
impact the performance of the transmission.
There are two basic categories of connectors
773
01:35:45,390 --> 01:35:53,190
there is the UPC the ultra physical contact.
This connector has a back reflection rating
774
01:35:53,190 --> 01:36:01,750
of around a negative 55 decimal loss. Then
there's the AAPC the angle the physical connector,
775
01:36:01,750 --> 01:36:08,210
which has a back reflection rating of around
a negative 70 decibel loss, making it the
776
01:36:08,210 --> 01:36:15,170
better performing connector. Now let's talk
about fiber types. There's multimode fiber,
777
01:36:15,170 --> 01:36:22,690
which uses an infrared LED system to transmit
light down to the fiber. It sends multiple
778
01:36:22,690 --> 01:36:30,060
rays of lights down the cable at the same
time. It is used for shorter fiber runs under
779
01:36:30,060 --> 01:36:36,291
two kilometers. It is less expensive than
the other type of fiber cable and then we
780
01:36:36,291 --> 01:36:43,760
have single mode fiber SMF it uses a laser
diode arrangement to transmit light down the
781
01:36:43,760 --> 01:36:49,390
fiber. It only sends a single ray of light
down the cable. Even though my diagram depicts
782
01:36:49,390 --> 01:36:54,640
it is going straight, it still bounces down
the cladding but there's only one of them.
783
01:36:54,640 --> 01:37:03,110
It's used for longer runs that require high
speed and it can span more than 40 kilometers.
784
01:37:03,110 --> 01:37:09,930
So now let's talk about fiber optic cables
and connectors. In First up is the SC that
785
01:37:09,930 --> 01:37:15,610
is the subscriber connector or this square
connector. You can also call it a standard
786
01:37:15,610 --> 01:37:22,770
connector. An easy way to remember it is stick
in click it's a push pull type connector.
787
01:37:22,770 --> 01:37:28,490
Then we have the st the straight tip. You
can also think of this as stick and twist.
788
01:37:28,490 --> 01:37:36,020
It is a spring loaded twist lock type of connector.
There is also the LC which can be called the
789
01:37:36,020 --> 01:37:42,080
local connector or loosened connector or little
connector. It's a type of connector that uses
790
01:37:42,080 --> 01:37:50,240
a locking tab to secure the connection. Similar
to the LC is the mtrj the mechanical transfer
791
01:37:50,240 --> 01:37:58,590
register jack. It's a small form factor connector
that contains two fibers. And that also utilizes
792
01:37:58,590 --> 01:38:05,060
a locking tab to secure the connection. You
might also find a fiber optic coupler guess
793
01:38:05,060 --> 01:38:11,710
what it does, it's used to connect to fiber
optic cables back to back. Now that concludes
794
01:38:11,710 --> 01:38:19,260
this session on network cabling part two,
I talked about coaxial cabling, and I concluded
795
01:38:19,260 --> 01:38:28,950
with fiber optic cabling. Good day, I'm Brian
ferrill, and welcome to peace I t's session
796
01:38:28,950 --> 01:38:35,610
on network cabling, part three. Today I'm
going to be talking about media converters,
797
01:38:35,610 --> 01:38:40,920
and then I'm going to talk about some cabling
tools that you should know about. And with
798
01:38:40,920 --> 01:38:47,910
that, let's go ahead and begin today's session.
I will begin by discussing media converters.
799
01:38:47,910 --> 01:38:55,850
It is not uncommon to be in a situation where
network contains more than one type of cabling.
800
01:38:55,850 --> 01:39:00,440
This can lead to a situation where there's
a desire to connect different types of media
801
01:39:00,440 --> 01:39:07,330
together in order to make a cohesive or single
network. Thankfully, media converters are
802
01:39:07,330 --> 01:39:12,950
readily available. The issue of trying to
connect these disparate types of transmission
803
01:39:12,950 --> 01:39:19,540
together mostly comes into play when you're
trying to join a fiber optic transmission
804
01:39:19,540 --> 01:39:25,980
to a copper wire infrastructure. And that's
actually represented in the types of readily
805
01:39:25,980 --> 01:39:31,870
available media converters that are out there.
The most common media converters will connect
806
01:39:31,870 --> 01:39:38,730
single mode fiber to Ethernet, or multimode
fiber to Ethernet or single mode fiber to
807
01:39:38,730 --> 01:39:47,310
multimode fiber. And finally, there is a fiber
to coaxial cabling media converter. You need
808
01:39:47,310 --> 01:39:55,510
to be aware that these devices are out there
to help you create a solid network. Now let's
809
01:39:55,510 --> 01:40:02,250
move on to cabling tools. So every technician
should put some thought into the tools that
810
01:40:02,250 --> 01:40:08,500
are in his or her toolbox. It is often said
that you get what you pay for. And that is
811
01:40:08,500 --> 01:40:14,260
very true with tools. While a good technician
can get away with buying the most inexpensive
812
01:40:14,260 --> 01:40:21,150
tools, by spending a little more money for
a better tool that can often make the task
813
01:40:21,150 --> 01:40:27,070
easier and ultimately make the technician
more efficient. But you also need to be aware
814
01:40:27,070 --> 01:40:35,050
that you can spend more money than is necessary
and not utilize all of the features in a given
815
01:40:35,050 --> 01:40:41,080
tool. So you need to find that balance point
between spending too much money and not spending
816
01:40:41,080 --> 01:40:47,130
enough money to become a really efficient
technician. Now let's move on to the tools
817
01:40:47,130 --> 01:40:53,960
themselves. And we'll begin with crimpers
crimpers are used to place cable ends on cables.
818
01:40:53,960 --> 01:41:00,020
They can be designed to work with a single
type of cable, as in twisted pair wire with
819
01:41:00,020 --> 01:41:05,590
multiple types of cable. I've seen some crimpers
that have been able to work with RJ elevens
820
01:41:05,590 --> 01:41:13,900
rj 45 and with a coaxial f connector, next
step or wire strippers. wire strippers are
821
01:41:13,900 --> 01:41:20,000
used to remove the insulating covers on wires
and cables. Many are designed to just cut
822
01:41:20,000 --> 01:41:26,692
through the insulation without damaging the
cable contained within that insulation. But
823
01:41:26,692 --> 01:41:31,610
some are also designed to cut all the way
through the cable so that excess cabling can
824
01:41:31,610 --> 01:41:36,660
be trimmed. When you're using those to cut
insulation, you need to be careful that you
825
01:41:36,660 --> 01:41:42,550
don't cut the underlying cable. Then there
are punchdown tools. These are used to secure
826
01:41:42,550 --> 01:41:48,420
cable wires in it punch down blocks. A good
punch down tool will trim the ends at the
827
01:41:48,420 --> 01:41:54,680
same time as it places the wire in the punch
down block. Then there are cable testers.
828
01:41:54,680 --> 01:42:01,420
These are used to test cables for common problems
as in mis configuration of the ends or incorrect
829
01:42:01,420 --> 01:42:08,430
pin outs. Cable testers will often test for
the cable standard used either the T 568 A
830
01:42:08,430 --> 01:42:14,711
or the T 560 a b or they can tell you whether
or not you've created a crossover cable. Cable
831
01:42:14,711 --> 01:42:21,150
testers will test for shorts or breaks in
the continuity of the cable. Some types of
832
01:42:21,150 --> 01:42:27,550
testers can also test for cable length and
quality. These type of testers are called
833
01:42:27,550 --> 01:42:34,560
cable certifiers. Then we have the TDR the
time domain reflectometer. Now this is a cable
834
01:42:34,560 --> 01:42:40,760
tester for copper cabling that can determine
the length of a segment and the electrical
835
01:42:40,760 --> 01:42:47,840
characteristics of the cable. Also, a TDR
can tell you where break is in a segment.
836
01:42:47,840 --> 01:42:55,090
A TDR is capable of performing all of the
same tests that a cable tester can. But they
837
01:42:55,090 --> 01:43:00,860
are much more expensive than a standard cable
tester. This is where you can spend too much
838
01:43:00,860 --> 01:43:07,750
money and not utilize all of the features
available in the tool. Let's conclude this
839
01:43:07,750 --> 01:43:14,890
with the OTDR the optical time domain reflectometer.
It performs all of the same functions that
840
01:43:14,890 --> 01:43:22,840
a TDR can but it is specifically used for
fiber optic cabling. Now that concludes this
841
01:43:22,840 --> 01:43:29,110
session on network cabling, part three. I
briefly talked about media converters, and
842
01:43:29,110 --> 01:43:39,700
then I brought up some cabling tools that
you need to know about. Hello, I'm Brian ferrill,
843
01:43:39,700 --> 01:43:45,980
and welcome to pcit session on network topologies.
Today we're going to discuss what a topology
844
01:43:45,980 --> 01:43:51,461
is. Then we're going to discuss peer to peer
and client server networking. And then we're
845
01:43:51,461 --> 01:43:58,540
going to talk about some common network topologies.
And with that, let's go ahead and begin this
846
01:43:58,540 --> 01:44:06,590
session. So what is a topology? Well, a topology
is basically a map that can be used to describe
847
01:44:06,590 --> 01:44:13,190
how a network is laid out or how a network
functions. A network topology can be described
848
01:44:13,190 --> 01:44:19,530
as either being logical or physical. a logical
topology describes the theoretical signal
849
01:44:19,530 --> 01:44:26,091
path, while the physical topology describes
the physical layout of the network. And you
850
01:44:26,091 --> 01:44:32,710
should know that a logical and physical topology
don't need to match. And with that, let's
851
01:44:32,710 --> 01:44:40,280
move on to peer to peer versus the client
server networks. So are these really topologies?
852
01:44:40,280 --> 01:44:45,370
No, not really. They don't describe the signal
path or the physical layout of the network.
853
01:44:45,370 --> 01:44:51,160
But yes, they are topologies because they
do describe how the network function. So that's
854
01:44:51,160 --> 01:44:56,920
why they're here in this discussion. Now in
a peer to peer topology, the nodes control
855
01:44:56,920 --> 01:45:03,620
and grant access to resources on the network.
No one node or group of nodes controls access
856
01:45:03,620 --> 01:45:11,280
to a single specific type of resource. There's
no real server present. Each node is responsible
857
01:45:11,280 --> 01:45:19,260
for the resources it's willing to share. No
client server topology differs. Network resource
858
01:45:19,260 --> 01:45:26,130
access is controlled by a central server or
servers. A server determines what resources
859
01:45:26,130 --> 01:45:31,530
get shared, who is allowed to use those resources.
And even when those resources can be used.
860
01:45:31,530 --> 01:45:39,250
Now, in the small office home office, it's
common to find a hybrid topology. That's where
861
01:45:39,250 --> 01:45:45,630
a combination of peer to peer and client server
networking is, you know, let's move on to
862
01:45:45,630 --> 01:45:52,430
some common network topology models. The first
one we're going to discuss is the bus. The
863
01:45:52,430 --> 01:45:58,160
original Ethernet standard established a bus
topology for the network, both logically and
864
01:45:58,160 --> 01:46:04,590
physically. And what I mean by a bus topology
is the signal traveled along a predetermined
865
01:46:04,590 --> 01:46:09,550
path from end to end, it went from one direction
to the other direction, and then it could
866
01:46:09,550 --> 01:46:16,280
come back. Now as time went on, the bus developed
some mechanical problems that led to the development
867
01:46:16,280 --> 01:46:22,120
of different physical topologies. But the
logical topology remained the same in order
868
01:46:22,120 --> 01:46:28,970
to maintain backward compatibility. So when
we discuss Ethernet networks, the logical
869
01:46:28,970 --> 01:46:35,960
topology is always a bus topology, while the
physical topology can be different. So let's
870
01:46:35,960 --> 01:46:41,120
talk about the bus. Again, the signal traverses
from one end of the network to the other,
871
01:46:41,120 --> 01:46:47,660
no break in the line breaks the network, the
ends of the bus line needed to be terminated
872
01:46:47,660 --> 01:46:53,380
in order to prevent signal bounce. And what
that means is that if there was a break or
873
01:46:53,380 --> 01:46:57,960
the ends of the line were not terminated,
when the signal got to the end, it would bounce
874
01:46:57,960 --> 01:47:04,630
back through and create a storm. In a bus
topology, the network cable is the central
875
01:47:04,630 --> 01:47:11,310
point. Now kind of related to the bus is the
ring, it's a bus line with the endpoint connected
876
01:47:11,310 --> 01:47:18,280
together, a break in the ring breaks the ring.
In a ring topology, it's common to use two
877
01:47:18,280 --> 01:47:24,500
rings multiple rings that can rotate the safeguards
against a break in one ring bringing down
878
01:47:24,500 --> 01:47:30,140
the whole network. Now ring topologies are
not very common anymore in the land. But they're
879
01:47:30,140 --> 01:47:37,860
still used in the wide area network, especially
when sonet or SDH is used. Moving on from
880
01:47:37,860 --> 01:47:45,080
the ring we have the star, the nodes radiate
out from a central point. Now when a star
881
01:47:45,080 --> 01:47:50,430
topology is implemented with a hub, a break
in a segment brings down the whole bus, because
882
01:47:50,430 --> 01:47:55,620
the hub retransmits out all ports. Now when
it's implemented with a switch of braking,
883
01:47:55,620 --> 01:48:01,940
the segment only brings down that segment,
it is the most common implementation in the
884
01:48:01,940 --> 01:48:08,860
modern LAN. Then there's the mesh. A true
mesh topology is when all nodes are connected
885
01:48:08,860 --> 01:48:14,890
to all other nodes, that's a full mesh. Now,
those aren't very common because they are
886
01:48:14,890 --> 01:48:21,080
expensive and difficult to maintain. But it's
common to find partial meshes. That's where
887
01:48:21,080 --> 01:48:27,630
there are multiple paths between nodes. Now
everyone knows at least one partial mesh network
888
01:48:27,630 --> 01:48:33,620
and that would be the internet. Now let's
move on to the point to point topology. That's
889
01:48:33,620 --> 01:48:38,690
where two nodes or systems are connected directly
together. Now if you're talking about two
890
01:48:38,690 --> 01:48:44,180
PCs, that's when they use a crossover cable
to create a point to point topology. There's
891
01:48:44,180 --> 01:48:50,790
no central device to manage the connection.
Now this is still a common topology when implemented
892
01:48:50,790 --> 01:48:58,280
across a LAN connection utilizing a T one
line. We also need to discuss point to multipoint.
893
01:48:58,280 --> 01:49:05,420
In a point to multipoint topology a central
device controls the paths to all other devices.
894
01:49:05,420 --> 01:49:11,280
This differs from the star in that the central
device is intelligent. Now wireless networks
895
01:49:11,280 --> 01:49:18,310
often implement point to multipoint topologies.
When the wireless access point sends all devices
896
01:49:18,310 --> 01:49:25,160
on the network receive the data. But when
a device sends its messages only passed along
897
01:49:25,160 --> 01:49:32,591
to the destination. It's also a common topology
when implementing a win across a packet switch
898
01:49:32,591 --> 01:49:41,420
network. Now let's discuss MPLS MPLS is multiprotocol
Label Switching and it is a topology that's
899
01:49:41,420 --> 01:49:47,720
used to replace both frame relay switching
in ATM switching. It's a topology because
900
01:49:47,720 --> 01:49:53,801
it specifies a signal path in layout. MPLS
is used to improve the quality of service
901
01:49:53,801 --> 01:50:01,470
and flow of network traffic. It uses label
edge routers, le RS which is MPLS labels to
902
01:50:01,470 --> 01:50:07,830
incoming packets if they don't already have
them know the Le RS and the labels and pass
903
01:50:07,830 --> 01:50:15,080
the packets along to lsrs Label Switching
router, these forward packets based on their
904
01:50:15,080 --> 01:50:22,421
MPLS labels. That's what makes this a topology.
Now that concludes this session on network
905
01:50:22,421 --> 01:50:27,920
topologies. We discussed what a topology is.
Then we discussed the differences between
906
01:50:27,920 --> 01:50:33,450
peer to peer and client server networking.
And then I brought up some common network
907
01:50:33,450 --> 01:50:42,360
topology models that you should know. Good
day. I'm Brian ferrill, and welcome to pace
908
01:50:42,360 --> 01:50:49,610
I t's session on network infrastructure implementations.
Today I'm going to be talking about design
909
01:50:49,610 --> 01:50:55,740
versus function. And then I'm going to talk
about categories of different networks. In
910
01:50:55,740 --> 01:51:01,990
with that, let's go ahead and begin the session.
Let's begin this session by talking about
911
01:51:01,990 --> 01:51:08,350
the difference between design and function.
when describing a network, you have a couple
912
01:51:08,350 --> 01:51:14,600
of different options are you describing its
design or its function? If you are going to
913
01:51:14,600 --> 01:51:21,020
describe its design, then the first place
to start is to describe its topology? Is it
914
01:51:21,020 --> 01:51:26,930
a bus network is it a star network or a point
to point but if you're going to describe how
915
01:51:26,930 --> 01:51:34,600
the network functions, then the first place
to start is to describe the category or infrastructure
916
01:51:34,600 --> 01:51:43,201
implementation of that network. And with that,
let's move on to categories of networks. First
917
01:51:43,201 --> 01:51:50,800
up is the local area network or the LAN. Most
lands are encompassed by a single network
918
01:51:50,800 --> 01:51:58,080
address range, that address range may be broken
up into subgroups. Through the use of virtual
919
01:51:58,080 --> 01:52:06,630
local area networks. VLANs. A LAN can span
anywhere from a small area like a single room
920
01:52:06,630 --> 01:52:13,880
to a whole building or a small group of buildings,
the land tends to be the highest speed network,
921
01:52:13,880 --> 01:52:20,690
it is becoming more common to see 10 gigabits
per second networking on the land. The most
922
01:52:20,690 --> 01:52:29,520
common types of network on the land are the
802 dot three or Ethernet and or the 802 dot
923
01:52:29,520 --> 01:52:37,190
11 or wireless local area network. These are
the most common types of network found on
924
01:52:37,190 --> 01:52:45,400
the LAN then there is the Metropolitan Area
Network or the man, it is larger than land.
925
01:52:45,400 --> 01:52:52,470
Most often it contains multiple local area
networks. mans or Metropolitan Area Networks
926
01:52:52,470 --> 01:52:59,920
are often owned by municipalities. When a
man is owned by a private entity, it is sometimes
927
01:52:59,920 --> 01:53:09,000
called a campus Area Network, then there is
the win the wide area network. Now a win spans
928
01:53:09,000 --> 01:53:16,410
significant geographic distances, they can
be described as a network of networks in the
929
01:53:16,410 --> 01:53:23,610
best example of a win is the internet. So
how do you tell when a man becomes a win?
930
01:53:23,610 --> 01:53:30,900
Well, as a general rule, if all of the infrastructure
implementation has a single owner, then it
931
01:53:30,900 --> 01:53:37,950
is not a win. If it's large, it'll be a man.
And if it's not quite so large, it'll be a
932
01:53:37,950 --> 01:53:46,610
LAN. But it's really easy to tell a personal
Area Network a pan. Why, because they are
933
01:53:46,610 --> 01:53:54,150
extremely distance and size limited. Most
often a pan is a connection between only two
934
01:53:54,150 --> 01:54:00,370
devices. Common examples include a Bluetooth
connection between a keyboard and a computer
935
01:54:00,370 --> 01:54:07,320
that's a pan, then there are infrared or IR
connections between a smartphone and a printer.
936
01:54:07,320 --> 01:54:14,850
That's a pan. Another example of a pan is
near field communication, which is now becoming
937
01:54:14,850 --> 01:54:22,530
seen between a smartphone and a payment terminal.
The pan tends to have low throughput of data
938
01:54:22,530 --> 01:54:28,880
and low power output, they don't consume a
whole lot of power. As the distance between
939
01:54:28,880 --> 01:54:37,280
devices increase, the throughput on a pan
will decrease. Now a couple of special categories
940
01:54:37,280 --> 01:54:44,700
of networks in first is the supervisory control
and data acquisition network, the scatter
941
01:54:44,700 --> 01:54:52,940
network. Now a scatter network is a type of
industrial control system or ICS that is designed
942
01:54:52,940 --> 01:54:59,740
to control large scale deployments of equipment.
The control equipment is usually at more than
943
01:54:59,740 --> 01:55:07,780
one sight. Scatter is often deployed in energy
distribution systems by utility companies.
944
01:55:07,780 --> 01:55:15,440
Scatter uses a distributed control system
or DCs to communicate with programmable logic
945
01:55:15,440 --> 01:55:22,050
controllers, PLCs and or remote terminals
to control the equipment and processes from
946
01:55:22,050 --> 01:55:28,060
a central location. So they have a central
location to control equipment that's at remote
947
01:55:28,060 --> 01:55:36,580
locations. Scattered networks are often proprietary,
and often require additional training to understand
948
01:55:36,580 --> 01:55:44,770
them and operate them. The last special mention
on categories of networks is the media net.
949
01:55:44,770 --> 01:55:51,690
It's a network designed and implemented specifically
to handle voice and video. They are designed
950
01:55:51,690 --> 01:55:58,600
and implemented to remove quality of service
issues like latency, or jitter that can occur
951
01:55:58,600 --> 01:56:05,880
in other types of infrastructure. A video
teleconference network, or VTC is an example
952
01:56:05,880 --> 01:56:13,910
of a media net. They are often implemented
as its own infrastructure, or as a sub infrastructure
953
01:56:13,910 --> 01:56:22,130
of a larger network. That concludes this session
on network infrastructure implementations.
954
01:56:22,130 --> 01:56:28,550
I talked about the differences between design
and function of networks. And I concluded
955
01:56:28,550 --> 01:56:38,690
with a discussion on the different categories
of networks. Hello, I'm Brian ferrill, and
956
01:56:38,690 --> 01:56:46,860
welcome to peace I t's session on the introduction
to ipv4, part one. Today we're going to be
957
01:56:46,860 --> 01:56:54,190
talking about the purpose of IP addressing.
And then we're going to move on to some ipv4
958
01:56:54,190 --> 01:56:59,580
address properties. There's a whole lot of
ground to cover, and we need to do it quickly.
959
01:56:59,580 --> 01:57:05,260
So let's go ahead and begin this session.
Of course, we're going to start with the purpose
960
01:57:05,260 --> 01:57:13,790
of IP addressing. When Bob on network a wants
to view a webpage hosted on a server on network
961
01:57:13,790 --> 01:57:21,470
C, how does Bob's computer know where to send
him? Well, somehow Bob has gotten that server's
962
01:57:21,470 --> 01:57:33,590
IP address, either an ipv4 format, or ipv6.
IP addresses are the location of a PC or server
963
01:57:33,590 --> 01:57:42,150
or some other network device that identifies
it by both its network location and host location
964
01:57:42,150 --> 01:57:49,720
within that network. IP addressing provides
a logical addressing scheme for our computers,
965
01:57:49,720 --> 01:57:55,950
so that they can communicate on networks.
Being logical means that the IP address can
966
01:57:55,950 --> 01:58:02,250
be changed with minimal fuss at any time.
Unlike the MAC address, or the media access
967
01:58:02,250 --> 01:58:10,170
control address, which is physically embedded
into the device. On the other hand, IP addresses
968
01:58:10,170 --> 01:58:17,360
are programmed and are easily change. Now
that we know the purpose of IP addressing,
969
01:58:17,360 --> 01:58:28,160
let's move on to sum ipv4 address properties.
ipv4 is made up of a 32 bit binary number.
970
01:58:28,160 --> 01:58:35,940
That means there are two to the 32nd power,
possible address combinations. That gives
971
01:58:35,940 --> 01:58:50,200
us 4,294,967,296. Possible address combinations.
With all of these possibilities, a process
972
01:58:50,200 --> 01:58:57,400
needed to be developed to keep everything
neat and tidy. And most of all, find double
973
01:58:57,400 --> 01:59:03,720
the implementation of a subnet mask was the
answer. And I'll get to that subnet mask in
974
01:59:03,720 --> 01:59:10,190
just a moment. Something that you will find
useful is learning how to convert from binary
975
01:59:10,190 --> 01:59:17,900
to decimal. Now decimal is base two, that
means there are only zeros and ones, as opposed
976
01:59:17,900 --> 01:59:23,210
to the base 10 that we're all used to dealing
with. If you would like more information on
977
01:59:23,210 --> 01:59:29,740
how to convert from decimal to binary or binary
to decimal, you can go to that website that's
978
01:59:29,740 --> 01:59:36,720
listed under this heading. So now let's talk
about the initial properties of ipv4. It is
979
01:59:36,720 --> 01:59:43,850
a 32 bit binary number. As I said before,
it's divided into four sets of eight called
980
01:59:43,850 --> 01:59:52,610
octets. These are separated by periods or
decimals. Each octet is eight bits which equals
981
01:59:52,610 --> 02:00:00,350
one byte. We often represent ipv4 addresses
in a human friendly format. That's called
982
02:00:00,350 --> 02:00:09,170
dotted decimal. Now when we look at this address
192 dot 168 dot 1.9. That is an IP address,
983
02:00:09,170 --> 02:00:15,150
but we don't know which portion is the network
or which portion is the host. To be able to
984
02:00:15,150 --> 02:00:21,280
resolve this, it requires the use of a mask,
which determines or defines which portion
985
02:00:21,280 --> 02:00:28,680
is which this mask is called the subnet mask.
And the subnet mask has the same format as
986
02:00:28,680 --> 02:00:36,390
the IP address, as in it's 32 bits, and it's
represented in dotted decimal format. So let's
987
02:00:36,390 --> 02:00:42,580
take a look at how an IP address and subnet
mask operate together. So we're going to begin
988
02:00:42,580 --> 02:00:54,180
with 192 dot 168 dot 1.9 with a subnet mask
of 25525525 5.0. Now the 192 dot 168 dot nine
989
02:00:54,180 --> 02:01:03,490
is the IP address. Like I said, in the other
portion, the 25525525 5.0 is the subnet mask.
990
02:01:03,490 --> 02:01:10,160
And it's easiest to show how the subnet masks
by converting that dotted decimal back into
991
02:01:10,160 --> 02:01:16,690
binary. So we can do that by deconstructing
the IP address. So the first octet would be
992
02:01:16,690 --> 02:01:26,950
one, one, followed by six zeros, that equals
192. The second octet is 10101, followed by
993
02:01:26,950 --> 02:01:33,960
three zeros, that equals 168. That third octets
really easy. It's seven zeros followed by
994
02:01:33,960 --> 02:01:40,000
a one. And then we have the fourth octet,
which is four zeros, a one, two zeros and
995
02:01:40,000 --> 02:01:47,240
a one that equals nine. Now if we deconstruct
the subnet mask, what we have is we have three
996
02:01:47,240 --> 02:01:52,780
octets that are full of ones and one octet
that's full of zeros that represents that
997
02:01:52,780 --> 02:02:03,230
25525525 5.0. Now if we put the subnet mask
under the representation of the IP address,
998
02:02:03,230 --> 02:02:11,220
anything that's not covered by a one in the
subnet mask is a part of the host address.
999
02:02:11,220 --> 02:02:16,050
Everything that is covered by a one is the
network address. So what we have for that
1000
02:02:16,050 --> 02:02:23,780
IP address is that 192 dot 168 dot one is
the network portion of the address. And the
1001
02:02:23,780 --> 02:02:30,560
node portion of the address is the nine. And
that's how the IP address and subnet mask
1002
02:02:30,560 --> 02:02:38,310
work together to define the network and the
node. Now that concludes this session on the
1003
02:02:38,310 --> 02:02:45,860
introduction to ipv4 part one, we talked about
the purpose of IP addressing and then we moved
1004
02:02:45,860 --> 02:02:57,320
on to some ipv4 address properties. Hello,
I'm Brian ferrill. And welcome to peace I
1005
02:02:57,320 --> 02:03:04,760
t's session on the introduction to ipv4 part
two. Today we're going to talk about classes
1006
02:03:04,760 --> 02:03:13,091
of ipv4 addresses. And then we're going to
move on to Classless ipv4 addressing and we
1007
02:03:13,091 --> 02:03:21,800
will conclude with a brief discussion on subnetting
ipv4 addresses. There's a whole lot of technical
1008
02:03:21,800 --> 02:03:28,140
information to cover, so let's go ahead and
begin the session. Let's begin by talking
1009
02:03:28,140 --> 02:03:37,780
about classes of ipv4 addresses. Internet
Protocol Version four ipv4 is a binary addressing
1010
02:03:37,780 --> 02:03:44,420
scheme that's used for networking. It was
initially finalized as a standard in 1981.
1011
02:03:44,420 --> 02:03:51,300
ipv4 is a common network addressing scheme
that is still being deployed today. There
1012
02:03:51,300 --> 02:03:57,510
is an issue though with ipv4. Because of its
structure and the growth and popularity of
1013
02:03:57,510 --> 02:04:05,320
the internet. Most of the world has run out
of assignable ipv4 addresses. But thanks to
1014
02:04:05,320 --> 02:04:14,050
some forethought, it's still a valid scheme.
Today, we need to talk about classes of ipv4
1015
02:04:14,050 --> 02:04:19,400
addresses and we begin with a class a network
address. Class A networks have an address
1016
02:04:19,400 --> 02:04:33,550
range of zero to 127 in the first octet, that
gives us addresses from 0.0 dot 0.0 up to
1017
02:04:33,550 --> 02:04:40,820
127.255255255. The first octet on the left
has a binary representation that always begins
1018
02:04:40,820 --> 02:04:53,070
with a zero. This gives us a possible 16,777,214
host addresses and the subnet mask with a
1019
02:04:53,070 --> 02:05:02,900
class a network is always 255 dot 0.0 dot
zero then there are classes B network addresses,
1020
02:05:02,900 --> 02:05:11,750
they have an address range of 128 to 191 in
the first octet, that means that class B networks
1021
02:05:11,750 --> 02:05:26,790
can have a range of 128.0 dot 0.0 up to 191.255255255.
The first octet on the left always has a binary
1022
02:05:26,790 --> 02:05:34,290
representation that begins with a one zero.
Now Class B network addresses give us a possible
1023
02:05:34,290 --> 02:05:45,840
65,534 hosts in the subnet mask used with
a Class B network is always 255255 dot 0.0.
1024
02:05:45,840 --> 02:05:50,840
Then there are Class C network addresses and
they have an address range in the first octet
1025
02:05:50,840 --> 02:06:01,940
of 192 up to 223. That means that we have
an address range of 192.0 dot 0.0, up through
1026
02:06:01,940 --> 02:06:14,131
223.255255255. And that first octet on the
left always begins with a one zero. Class
1027
02:06:14,131 --> 02:06:23,090
C network addresses give us a possible 254
post addresses or node addresses and the subnet
1028
02:06:23,090 --> 02:06:32,760
mask with a Class C is always 25525525 5.0.
The last class of address that you need to
1029
02:06:32,760 --> 02:06:41,190
concern yourself with is the Class D network
address. It has an address range of 224 up
1030
02:06:41,190 --> 02:06:49,530
through 239 in the first octet, which means
that it can range from 220 4.0 dot 0.0 up
1031
02:06:49,530 --> 02:07:01,100
through 239.255255255. In that first octet
on the left has a binary representation of
1032
02:07:01,100 --> 02:07:11,700
1110. So the first four bits are always taken
and they are always 1110. Now subnet masks
1033
02:07:11,700 --> 02:07:19,430
are not defined for class the networking class
the network addresses are used for multicast
1034
02:07:19,430 --> 02:07:26,440
communication. And finally, we have a special
class of addresses Well, kind of a class of
1035
02:07:26,440 --> 02:07:33,490
addresses, and that involves automatic private
IP addressing up PIPA. In some cases, the
1036
02:07:33,490 --> 02:07:42,570
Dynamic Host Configuration Protocol DHCP process
may fail. In these cases, a node or host will
1037
02:07:42,570 --> 02:07:50,060
self configure an IP PIPA address. Now within
a PIPA address, the first two octets are always
1038
02:07:50,060 --> 02:08:00,290
168.2 54. And if you see that in your IP configuration,
you know that you have a DHCP problem. So
1039
02:08:00,290 --> 02:08:06,350
one of the first methods that they use to
conserve the ipv4 address space was they broke
1040
02:08:06,350 --> 02:08:14,170
them out into public and private IP addresses.
public IP addresses are routable. And being
1041
02:08:14,170 --> 02:08:22,380
routable means that each public IP address
is unique. There can only be one. Now public
1042
02:08:22,380 --> 02:08:30,180
IP addresses are not flexible, you are assigned
to your network space, you're not really given
1043
02:08:30,180 --> 02:08:37,030
a choice what your public IP address is going
to be. And then there are the private IP addresses.
1044
02:08:37,030 --> 02:08:43,110
These are non routable. They do not need to
be completely unique throughout the world.
1045
02:08:43,110 --> 02:08:48,040
They only have to be unique on their network.
The first one that we're going to discuss
1046
02:08:48,040 --> 02:08:53,860
is the class a license, there is only one
class a license, you have a possible address
1047
02:08:53,860 --> 02:09:05,830
range of 10.0 dot 0.0 up through 10.255255255.
Next up is the class B license. There are
1048
02:09:05,830 --> 02:09:13,460
16 possible network addresses, not networking
O's, but just network addresses available
1049
02:09:13,460 --> 02:09:23,550
in a class B license. They have an address
range of 172 dot 16 dot 0.0 up through 172
1050
02:09:23,550 --> 02:09:34,780
dot 31.255255. And last but not least is the
class C license. There are 256 Class C licenses
1051
02:09:34,780 --> 02:09:47,500
with a possible address range of 192.1 68
dot 0.0 up through 192.1 68.255255. Now private
1052
02:09:47,500 --> 02:09:54,540
IP addresses is highly flexible. You get to
assign the network space it's not assigned
1053
02:09:54,540 --> 02:10:02,900
to you. Now let's move on to Classless ipv4.
Addressing Now the classes of addresses actually
1054
02:10:02,900 --> 02:10:09,790
limited the flexibility of ipv4. Part of the
reason for that was that the first routing
1055
02:10:09,790 --> 02:10:15,860
protocols required the class structure. And
you would think that with over 4 billion possible
1056
02:10:15,860 --> 02:10:21,790
IP addresses that we'd still have flexibility,
but we really didn't. classless addressing,
1057
02:10:21,790 --> 02:10:28,680
which is called classless inter domain routing
or cider was developed to slow the growth
1058
02:10:28,680 --> 02:10:36,400
of routing tables. It also slowed the exhaustion
of ipv4 addresses, it also created much more
1059
02:10:36,400 --> 02:10:43,341
flexibility, the subnet mask becomes fluid,
it's not rigid with cider addresses. It does
1060
02:10:43,341 --> 02:10:48,550
not affect the private address space ranges
though, even though the subnet mask is now
1061
02:10:48,550 --> 02:10:54,310
fluid, you still only have those range of
addresses available in with the introduction
1062
02:10:54,310 --> 02:11:01,510
of classless addressing subnetting is now
possible, and it's highly desirable. So let's
1063
02:11:01,510 --> 02:11:09,330
take a look at how cider notation works. And
we'll begin with 190 2.1 68 dot nine with
1064
02:11:09,330 --> 02:11:21,760
a subnet mask of 25525 5.0. With that becomes
is 190 2.1 68 dot 0.9 slash 24. That slash
1065
02:11:21,760 --> 02:11:29,360
24 represents all of the ones in the subnet
mask. And that's those first three octets
1066
02:11:29,360 --> 02:11:39,060
on the left that 255255255. And if you look
at that address, it's a Class C address, which
1067
02:11:39,060 --> 02:11:47,910
always has a 25525525 5.0 subnet mask, but
it now becomes fluid with cider, we can take
1068
02:11:47,910 --> 02:11:56,480
it and we can make it a 190 2.1 68.1 28.0
slash 23. And what that really represents
1069
02:11:56,480 --> 02:12:07,930
that slash 23 is a subnet mask of 25525 5.1
28.0. And that gives us a network of 190 2.1
1070
02:12:07,930 --> 02:12:23,720
68.1 28.0 which actually gives us a host range
of 190 2.1 68.1 28.1 through 190 2.1 68.1
1071
02:12:23,720 --> 02:12:36,010
29.2 54. That gives us 512 host addresses
as opposed to the possible 254. Now the broadcast
1072
02:12:36,010 --> 02:12:46,050
address for that network would be 190 2.1
68.1 29.2 55. So now let's move on to subnetting
1073
02:12:46,050 --> 02:12:54,180
ipv4 addresses. So what is subnetting? Well,
subnetting cuts address spaces into smaller
1074
02:12:54,180 --> 02:13:00,390
pieces. It takes one range of addresses and
splits it. This creates flexibility and network
1075
02:13:00,390 --> 02:13:07,920
design and creates efficiency in address space
utilization. So let's take a look at an example
1076
02:13:07,920 --> 02:13:16,590
of subnetting. This will involve a small office
network. So originally, we have a network
1077
02:13:16,590 --> 02:13:25,940
address of 223 dot 15 dot 1.0 slash 24. This
is a Class C private network and it gives
1078
02:13:25,940 --> 02:13:35,170
us a possible 254 hosts available. Why only
254 will because a host cannot be assigned
1079
02:13:35,170 --> 02:13:42,850
to the network address which is 223 dot 15
dot 1.0. And it can't use the broadcast address
1080
02:13:42,850 --> 02:13:51,170
which is 223 dot 15 dot 1.255. In this example,
with this network address, all the hosts in
1081
02:13:51,170 --> 02:13:57,580
the network can see all the other nodes. Now
let's say that for security considerations,
1082
02:13:57,580 --> 02:14:03,880
you want to split this into two networks.
Well, you can do this using sub netting. So
1083
02:14:03,880 --> 02:14:11,000
what you do is you take that slash 24 network
and you create two slash 25 networks. And
1084
02:14:11,000 --> 02:14:22,050
those would be 223 dot 15 dot 1.0 slash 25
and 223 dot 15.1 dot 128 slash 25. In this
1085
02:14:22,050 --> 02:14:29,900
situation, the first networks host address
range would be 223 dot 15 dot 1.1 up through
1086
02:14:29,900 --> 02:14:37,980
to 23 dot 15.1 dot 126. And why is that? Well,
because you can't use the network address
1087
02:14:37,980 --> 02:14:47,081
which is 223 dot 15 dot 1.0. And you can't
use the broadcast address which is 223 dot
1088
02:14:47,081 --> 02:14:53,730
1.1 27. The second address range that would
be created through this subnetting process
1089
02:14:53,730 --> 02:15:04,231
would give us a host range of 223 dot 15.1
dot 129 up through 223 dot 15.1 dot 254. That's
1090
02:15:04,231 --> 02:15:11,930
because you can't use the network address
which is 223 dot 15.1 dot 128. And you can't
1091
02:15:11,930 --> 02:15:21,000
use the broadcast address which is 223 dot
15 dot 1.255. Each of those subnets would
1092
02:15:21,000 --> 02:15:32,030
have 126 possible host addresses. So you took
your possible 254 hosts available in one network,
1093
02:15:32,030 --> 02:15:37,260
and you broke it down so that you now have
two separate networks, each that's capable
1094
02:15:37,260 --> 02:15:46,000
of having 126 hosts. And that's an example
of subnetting an ipv4 address. Now, that concludes
1095
02:15:46,000 --> 02:15:54,950
this session on the introduction to ipv4 part
two, I talked about classes of ipv4 addresses.
1096
02:15:54,950 --> 02:16:03,280
I then moved on to Classless ipv4 addressing
and we concluded with a brief discussion on
1097
02:16:03,280 --> 02:16:13,990
subnetting ipv4 addresses. Good day. I'm Brian
ferrill. And welcome to pace IITs session
1098
02:16:13,990 --> 02:16:20,420
on the introduction to ipv6. Today, we're
going to be talking about the ipv6 address
1099
02:16:20,420 --> 02:16:28,990
structure. And then we're going to move on
to ipv6 network transmissions. And with that,
1100
02:16:28,990 --> 02:16:35,030
let's go ahead and begin this session. Of
course, I'm going to begin by talking about
1101
02:16:35,030 --> 02:16:42,160
the ipv6 address structure. Now, ipv6 is the
answer to the question of what do we do about
1102
02:16:42,160 --> 02:16:50,179
running out of ipv4 addresses. Unlike ipv4,
ipv6, will provide enough Internet Protocol
1103
02:16:50,179 --> 02:16:59,179
IP addresses for the foreseeable future. Now,
shortly after the creation of ipv4 and its
1104
02:16:59,179 --> 02:17:06,801
implementation, the IAA na the organization
that's tasked with assigning routable IP addresses,
1105
02:17:06,801 --> 02:17:13,591
realized the available ipv4 address space
would not be enough in very short order if
1106
02:17:13,591 --> 02:17:19,740
nothing was done. The IAA na then said about
creating the replacement, and they initially
1107
02:17:19,740 --> 02:17:26,000
started by working on IPv. Five. While they
were working on IPv. Five, they found that
1108
02:17:26,000 --> 02:17:30,690
due to the popularity of the internet, which
was increasing at that point in time that
1109
02:17:30,690 --> 02:17:36,960
it wasn't going to be enough. So they scrapped
IPv five and began working on ipv6. Now the
1110
02:17:36,960 --> 02:17:47,380
i na is confident that ipv6 will function
as the replacement for ipv4 for many decades
1111
02:17:47,380 --> 02:17:53,440
to come. Why are they so confident? Well,
we'll get to that here in just a moment. Now,
1112
02:17:53,440 --> 02:18:00,490
ipv6 works at layer three of the OSI model
just like ipv4 does. layer three of the OSI
1113
02:18:00,490 --> 02:18:07,179
model is also known as the network layer,
and its major focus is logical network and
1114
02:18:07,179 --> 02:18:15,790
host addresses. ipv6, his job is to provide
logical network and host addresses to devices.
1115
02:18:15,790 --> 02:18:27,280
ipv6 is 128 bit binary addressing scheme as
opposed to ipv4 is 32 bits. The 128 bits are
1116
02:18:27,280 --> 02:18:34,139
grouped together in sets, with each set being
separated by a colon. Now each of these sets
1117
02:18:34,139 --> 02:18:42,200
is two bytes long and a byte is a bit for
human readability kind of the binary ipv6
1118
02:18:42,200 --> 02:18:49,010
number is converted to hexadecimal that's
base 16. With each hexadecimal number being
1119
02:18:49,010 --> 02:18:55,020
equal to four bits. Now those four bits can
actually be referred to as a nibble. Because
1120
02:18:55,020 --> 02:19:02,809
it's half of a bite. An ipv6 address is eight
sets of four hexadecimal numbers, each being
1121
02:19:02,809 --> 02:19:11,130
separated by a colon. That means that there
are over 340 undecillion addresses available
1122
02:19:11,130 --> 02:19:22,760
to ipv6. That's two to the 120/8 power, which
is roughly equal to 340 times 10 to the 36
1123
02:19:22,760 --> 02:19:29,420
power. See that number there? I'm not even
going to begin to read that one to you. So
1124
02:19:29,420 --> 02:19:37,219
now let's talk about ipv6 is local address
structure for the local address. The first
1125
02:19:37,219 --> 02:19:45,760
64 bits on the left represent the local network
in the last 64 bits on the right always represent
1126
02:19:45,760 --> 02:19:54,010
the host. The local address structure follows
the E UI or extended unique identifier format,
1127
02:19:54,010 --> 02:20:02,370
specifically the UI 64 format for those hosts
that have a 48 bit Mac MAC address that 48
1128
02:20:02,370 --> 02:20:09,580
bits is actually padded with an extra 16 bits
to make it 64 bits in length, you can always
1129
02:20:09,580 --> 02:20:15,740
tell a local address, which is also called
the link local address as it always begins
1130
02:20:15,740 --> 02:20:23,970
with an F v 80. With ipv6, every device gets
both a local address and it gets a global
1131
02:20:23,970 --> 02:20:32,050
address. Now the global address is unique,
there is only one and every device gets one,
1132
02:20:32,050 --> 02:20:39,510
the host address is still always the last
64 bits. But every device actually gets assigned
1133
02:20:39,510 --> 02:20:46,170
to a global network. The network portion is
actually composed of a routing prefix and
1134
02:20:46,170 --> 02:20:53,450
a subnet. This portion of the global address
structure follows the classless inter domain
1135
02:20:53,450 --> 02:20:59,220
routing or cider convention, with the number
that follows the slash denoting the routing
1136
02:20:59,220 --> 02:21:05,070
prefix. That's the part of the extremely global
network that you belong to. The subnet is
1137
02:21:05,070 --> 02:21:13,850
composed of the bits between the prefix and
the EU I 64 host address. Global ipv6 addresses
1138
02:21:13,850 --> 02:21:23,640
always begin in the range of 2000, up through
3999 in that first group of numbers on the
1139
02:21:23,640 --> 02:21:31,100
left. Now in most cases, the need for Dynamic
Host Configuration Protocol DHCP has been
1140
02:21:31,100 --> 02:21:38,720
eliminated. When implemented, ipv6 will auto
configure both the local and the global addresses
1141
02:21:38,720 --> 02:21:44,750
that are required for their networks. When
a device first comes online, it will use the
1142
02:21:44,750 --> 02:21:52,000
Neighbor Discovery Protocol NDP to discover
what the required network addresses are both
1143
02:21:52,000 --> 02:22:00,081
the local and global addresses. This allows
devices to configure its own ipv6 address
1144
02:22:00,081 --> 02:22:09,451
without an administrator's intervention. So
let's talk about ipv6 notation. The 128 bit
1145
02:22:09,451 --> 02:22:16,210
nature of ipv6 makes it cumbersome to write
out and it can take up unnecessary space.
1146
02:22:16,210 --> 02:22:21,030
Because of this, some rules were developed
to ease the burden and save space. When you're
1147
02:22:21,030 --> 02:22:29,230
looking at a group of ipv6 numbers. Any leading
zeros in a set can be dropped. The thing to
1148
02:22:29,230 --> 02:22:35,890
really remember about ipv6 is that only a
single set of consecutive zeros may be replaced
1149
02:22:35,890 --> 02:22:40,910
with the double colon. Why is that? Well,
because if you could do it more than once,
1150
02:22:40,910 --> 02:22:46,180
how would routers and other devices know how
many zeros to pad in there. Even with this
1151
02:22:46,180 --> 02:22:54,190
ability to shorten it? It's still difficult
for us to remember ipv6 addresses, but it
1152
02:22:54,190 --> 02:23:00,200
is still easier to write out and it still
conserves space within systems. Now let's
1153
02:23:00,200 --> 02:23:09,470
move on to types of ipv6 network transmissions.
And we begin with the unicast. unicast is
1154
02:23:09,470 --> 02:23:15,030
one to one communication. That is where a
specific device is sending network traffic
1155
02:23:15,030 --> 02:23:21,620
to another specific device. unicast can occur
on the local network, which remember always
1156
02:23:21,620 --> 02:23:28,280
begins with FC 80 or it can occur on the global
network. Then there's multicast, which is
1157
02:23:28,280 --> 02:23:35,350
one to a few communication. With multicast
a specific device is sending network traffic
1158
02:23:35,350 --> 02:23:42,330
to a specific group of devices that have registered
receive that traffic routers registered to
1159
02:23:42,330 --> 02:23:47,830
receive multicast transmissions that involve
the routing protocols that they are programmed
1160
02:23:47,830 --> 02:23:58,270
to use. With ipv6 multicast addresses always
begin with an F F. Both ipv6 and ipv4 use
1161
02:23:58,270 --> 02:24:06,560
both unicast and multicast transmissions.
A unique type of transmission to ipv6 is any
1162
02:24:06,560 --> 02:24:15,070
cast. Any cast is one to the closest communication.
This is where a specific device is sending
1163
02:24:15,070 --> 02:24:23,740
network traffic to a specific ipv6 address
that has been assigned to multiple devices.
1164
02:24:23,740 --> 02:24:31,131
The router only sends the communication to
the closest one, at least from its perspective.
1165
02:24:31,131 --> 02:24:38,700
Any cast transmission involves implementing
DHCP v six. Earlier I said we really don't
1166
02:24:38,700 --> 02:24:44,720
need to worry about DHCP anymore, but that's
only partially true. While ipv6 is capable
1167
02:24:44,720 --> 02:24:50,570
of auto configuring its own local and global
addresses in certain situations. That's not
1168
02:24:50,570 --> 02:25:00,350
always desirable. DHCP v six version sic can
be configured to hand out specific ipv6 addresses
1169
02:25:00,350 --> 02:25:07,440
Or duplicate ipv6 addresses when necessary.
That's useful for when load balancing a network
1170
02:25:07,440 --> 02:25:13,671
or when network and redundancy has been created.
Or when you have a user that has a tablet,
1171
02:25:13,671 --> 02:25:19,400
a cell phone and a laptop, and you want to
deliver the transmission to the closest device
1172
02:25:19,400 --> 02:25:27,830
the devices using at that point in time. That
is where DHCP v six comes in handy. ipv6 and
1173
02:25:27,830 --> 02:25:34,840
ipv4 are not compatible. But we can do what's
called a dual stack configuration. That's
1174
02:25:34,840 --> 02:25:42,070
where the network and devices on the network
receive both an ipv6 configuration and an
1175
02:25:42,070 --> 02:25:47,950
ipv4 configuration. Or we can use what's called
tunneling. There's six to four tunneling,
1176
02:25:47,950 --> 02:25:55,810
which is used to encapsulate an ipv6 data
packet and an ipv4 datagram, allowing that
1177
02:25:55,810 --> 02:26:03,730
ipv6 packet to travel across or through an
all ipv4 network. 64 tunneling can also be
1178
02:26:03,730 --> 02:26:10,950
called teredo tunneling. Now, that concludes
this session on the introduction to ipv6,
1179
02:26:10,950 --> 02:26:20,790
I talked about the ipv6 address structure.
And then I talked about ipv6 network transmissions.
1180
02:26:20,790 --> 02:26:30,721
Hello, I'm Brian ferrill, and welcome to pace
it session on special IP networking concepts.
1181
02:26:30,721 --> 02:26:35,640
Today I'm going to be talking about the media
access control address. And then I'm going
1182
02:26:35,640 --> 02:26:41,470
to talk about the difference between collision
domains and broadcast domains. And we're going
1183
02:26:41,470 --> 02:26:48,050
to conclude with types of network transmissions.
There's a whole bunch of technical information
1184
02:26:48,050 --> 02:26:54,160
to cover. So let's go ahead and begin this
session. Let's begin the formal part of this
1185
02:26:54,160 --> 02:27:02,080
session by discussing the media access control
address. All networking interfaces come with
1186
02:27:02,080 --> 02:27:10,370
their own special address already configured,
that would be the media access control address
1187
02:27:10,370 --> 02:27:17,710
the MAC address, the MAC address is often
referred to as the physical address or the
1188
02:27:17,710 --> 02:27:26,321
burned in address of the interface. While
MAC addresses may be changed or spoofed. Most
1189
02:27:26,321 --> 02:27:34,710
often it's set by the manufacturer and never
actually changes. Now switches and other OSI
1190
02:27:34,710 --> 02:27:42,990
layer two devices rely upon that MAC address
in order to get network packets to their correct
1191
02:27:42,990 --> 02:27:52,021
destinations. The MAC address has a specific
format. Actually it has two specific formats.
1192
02:27:52,021 --> 02:27:59,470
One is 48 bits in length, and the other is
64 bits in length. And both of them are represented
1193
02:27:59,470 --> 02:28:06,870
by hexadecimal numbers. Both formats can be
broken down into two parts, the organizationally
1194
02:28:06,870 --> 02:28:15,760
unique identifier or all UI, in the extended
unique identifier, the EU II, the Institute
1195
02:28:15,760 --> 02:28:23,900
of Electrical and Electronic Engineers, the
I triple E assigns all electronic manufacturers
1196
02:28:23,900 --> 02:28:33,130
their own Bo UI, which always makes up the
first portion of the MAC address. Each manufacturer
1197
02:28:33,130 --> 02:28:41,530
then assigns its own t UI to each device that
is produced. Usually it is the serial number
1198
02:28:41,530 --> 02:28:49,190
of that device. Theoretically, no two interfaces
will have the same MAC address, I need to
1199
02:28:49,190 --> 02:28:58,550
mention the EU I 64 format. ipv6 requires
that the node address or the MAC address be
1200
02:28:58,550 --> 02:29:07,801
in an EU ii 64 format. So that MAC address
has to be 64 bits in length. If the EU II
1201
02:29:07,801 --> 02:29:14,771
of the interface is only 24 bits in length,
it is actually split into two parts in 16
1202
02:29:14,771 --> 02:29:23,030
bits of padding are added to create the EU
I 64 format. Now let's discuss the difference
1203
02:29:23,030 --> 02:29:29,540
between collision domains and broadcast domains.
Before I can talk about collision domains
1204
02:29:29,540 --> 02:29:36,290
and broadcast domains, I need to talk about
carrier sense multiple access with collision
1205
02:29:36,290 --> 02:29:45,310
detection. All Ethernet networks use this
technology also called csma. With CD when
1206
02:29:45,310 --> 02:29:52,480
transmitting data in an Ethernet network,
all Ethernet devices have equal access to
1207
02:29:52,480 --> 02:30:00,760
the network media and are capable of transmitting
data at any time. This can lead to data collision
1208
02:30:00,760 --> 02:30:08,560
With csma CD, a device listens to the carrier
signal on the network media. If no other device
1209
02:30:08,560 --> 02:30:14,430
is transmitting, the device is free to send
data. If another device sends data at the
1210
02:30:14,430 --> 02:30:22,140
same time, a collision is possible, which
can corrupt the data. The devices listen for
1211
02:30:22,140 --> 02:30:27,570
collisions. That's the collision detection
part. If a collision occurs, the devices will
1212
02:30:27,570 --> 02:30:34,380
stop transmitting and wait a random period
of time before attempting to transmit again.
1213
02:30:34,380 --> 02:30:41,100
To do this, they use what is called a back
off algorithm. With that out of the way, now
1214
02:30:41,100 --> 02:30:47,040
let me explain what collision domains are.
Collision domains are an area of the network
1215
02:30:47,040 --> 02:30:54,221
where packets or network traffic can collide.
There are some devices that break up collision
1216
02:30:54,221 --> 02:31:00,511
domains, they can be broken up by switches,
bridges and routers, but not by hubs. On the
1217
02:31:00,511 --> 02:31:07,140
other hand, a broadcast domain is defined
as all the nodes that can be reached by a
1218
02:31:07,140 --> 02:31:14,810
broadcast transmission. all the nodes that
can be reached reside in the same network.
1219
02:31:14,810 --> 02:31:21,670
Broadcast traffic cannot pass routers. So
the domain is also defined by the subnet mask
1220
02:31:21,670 --> 02:31:29,960
in that subnet mask defines the network. Here's
a special note. Technically, ipv6 does not
1221
02:31:29,960 --> 02:31:39,800
use broadcast transmissions. ipv6 replaces
broadcast transmissions with multicast transmissions.
1222
02:31:39,800 --> 02:31:46,750
In what do you know, that's a good segue for
us to discuss types of network transmissions.
1223
02:31:46,750 --> 02:31:53,350
We're going to begin this section by talking
about types of ipv4 network transmissions
1224
02:31:53,350 --> 02:32:02,440
in First up is unicast. unicast is a specific
source address transmission going to a specific
1225
02:32:02,440 --> 02:32:09,800
source destination address, it can be thought
of as one to one communication, it's only
1226
02:32:09,800 --> 02:32:16,100
two devices transferring data between each
other, then there's multicast transmission.
1227
02:32:16,100 --> 02:32:23,300
This is where a specific source address transmission
is going to a set of registered destination
1228
02:32:23,300 --> 02:32:32,800
addresses. This is one to a few communication.
routers often use multicast transmissions
1229
02:32:32,800 --> 02:32:40,130
to track their routes and to make changes
to the routing tables. In finally their broadcast
1230
02:32:40,130 --> 02:32:47,420
transmissions. This is where a specific source
address transmission is going to all addresses
1231
02:32:47,420 --> 02:32:55,570
on the local network. This can be considered
as one to all communication because all devices
1232
02:32:55,570 --> 02:33:01,980
on the local network are going to be able
to receive this broadcast transmission. So
1233
02:33:01,980 --> 02:33:13,101
let's move on to types of ipv6 network transmissions.
In ipv6 uses unicast just like ipv4 does.
1234
02:33:13,101 --> 02:33:24,560
ipv6 also uses multicast, just like ipv4,
where ipv6 differs is with any cast transmission.
1235
02:33:24,560 --> 02:33:32,680
Any cast is where a specific source address
transmission is going to a specific ipv6 address
1236
02:33:32,680 --> 02:33:39,000
that has been assigned to multiple devices.
The router uses an algorithm to determine
1237
02:33:39,000 --> 02:33:46,760
which MAC address that has that specially
configured ipv6 address is closest in only
1238
02:33:46,760 --> 02:33:53,970
that device receives the anycast transmission,
any caste can be considered as one to the
1239
02:33:53,970 --> 02:34:02,080
closest communication. That concludes this
session on special IP networking concepts.
1240
02:34:02,080 --> 02:34:08,270
I talked about the MAC address, I talked about
the differences between a collision domain
1241
02:34:08,270 --> 02:34:16,181
and a broadcast domain. And then I concluded
with a discussion on the types of network
1242
02:34:16,181 --> 02:34:25,060
transmission. Hello, I'm Brian ferrill, and
welcome to peace I t's session on introduction
1243
02:34:25,060 --> 02:34:31,050
to routing concepts, part one. Today I'm going
to talk about the purpose of routing. And
1244
02:34:31,050 --> 02:34:36,130
then I'm going to move on to some basic routing
concepts. There's a fair amount of ground
1245
02:34:36,130 --> 02:34:44,150
to cover, so let's go ahead and begin this
session. First up is the purpose of routing.
1246
02:34:44,150 --> 02:34:49,530
The basic purpose of routing is to connect
different networks together to allow them
1247
02:34:49,530 --> 02:34:56,170
to communicate and pass data traffic between
them. Most often routing protocols are how
1248
02:34:56,170 --> 02:35:02,680
networks determine where to send network traffic.
That's the routes that they will take. In
1249
02:35:02,680 --> 02:35:08,120
these routing protocols build maps. Actually,
they build routing tables that we'll get to
1250
02:35:08,120 --> 02:35:15,010
that later, that they use for directing network
traffic. routing is what makes this interconnected
1251
02:35:15,010 --> 02:35:22,470
world function as well as it does. Networking
would be pure chaos without it as we'd have
1252
02:35:22,470 --> 02:35:30,920
no idea where to send traffic. Now let's move
on to some basic routing concepts. First up
1253
02:35:30,920 --> 02:35:38,980
is static routing. Static routing uses administrator
defined routes. Each router in a static routing
1254
02:35:38,980 --> 02:35:46,810
configuration must contain the route. A static
route from router a to router B requires that
1255
02:35:46,810 --> 02:35:54,160
router B has a static route back to router
a, in order for two way communication to take
1256
02:35:54,160 --> 02:36:01,260
place. If we had a static route from A to
B, and B didn't have one back to a, a could
1257
02:36:01,260 --> 02:36:07,870
send traffic to B but b could not send traffic
back to A. Now static routing is easy to set
1258
02:36:07,870 --> 02:36:15,341
up in small networks. But it's not so easy
to maintain. Networks change all the time.
1259
02:36:15,341 --> 02:36:20,500
With static routing. When a change occurs
in routers, the administrator has to go around
1260
02:36:20,500 --> 02:36:27,340
to each router and implement that change.
Then there's dynamic routing. This is where
1261
02:36:27,340 --> 02:36:34,480
routers use protocols in order to determine
the best route between two networks. The administrator
1262
02:36:34,480 --> 02:36:40,240
determines which protocols will be used on
the routers. In order for the routers to communicate,
1263
02:36:40,240 --> 02:36:46,280
they must all be using the same protocols.
There is an exception to that. And that's
1264
02:36:46,280 --> 02:36:53,340
route redistribution. An administrator can
configure a router to take one dynamic protocol
1265
02:36:53,340 --> 02:37:00,370
and transform it into a different routing
protocol to be used from that point on. This
1266
02:37:00,370 --> 02:37:06,300
is the only case when routing protocols can
be different across the network. routing protocols
1267
02:37:06,300 --> 02:37:12,400
can be stacked within a router that means
that there can be more than one dynamic routing
1268
02:37:12,400 --> 02:37:18,930
protocol programmed into a router. dynamic
routing is very fluid and dynamic in it's
1269
02:37:18,930 --> 02:37:26,431
what makes possible today's interconnected
world. The next concept is the default route.
1270
02:37:26,431 --> 02:37:31,201
The default route is the direction that a
router will send network traffic when there
1271
02:37:31,201 --> 02:37:38,270
is no known route in the routing table. The
default route is assigned by an administrator,
1272
02:37:38,270 --> 02:37:45,860
it is usually a designated interface on the
router or it is the next designated next hop
1273
02:37:45,860 --> 02:37:53,550
interface. Then there is the routing table.
The routing table is a list of known routes
1274
02:37:53,550 --> 02:38:00,960
to all known networks. From the routers perspective,
it is established by an administrator when
1275
02:38:00,960 --> 02:38:07,710
static routing is used. It is dynamically
built by routing protocols when dynamic routing
1276
02:38:07,710 --> 02:38:15,530
is employed. Each routing protocol maintains
its own routing table. Different routing protocols
1277
02:38:15,530 --> 02:38:23,530
may have different routes to the same network.
The loopback interface is an administratively
1278
02:38:23,530 --> 02:38:31,530
configured logical number assigned to a router
to ease administrative functions or routing
1279
02:38:31,530 --> 02:38:39,670
processes. Often the loopback interface is
a sign in an ipv4 address format, even when
1280
02:38:39,670 --> 02:38:46,080
ipv4 isn't used on the router. Many routing
protocols have been designed to take the loopback
1281
02:38:46,080 --> 02:38:53,660
interface into account when performing administrative
functions. The loopback interface may be completely
1282
02:38:53,660 --> 02:39:00,730
logical or a physical interface may be assigned
to be the loopback interface. Let's move on
1283
02:39:00,730 --> 02:39:07,110
to routing loops. A routing loop is a possible
problem that can be created if interconnected
1284
02:39:07,110 --> 02:39:13,660
routers have a breakdown in their routing
algorithms. When a routing loop occurs. network
1285
02:39:13,660 --> 02:39:19,170
traffic keeps looping through the routers
until some system or mechanism breaks the
1286
02:39:19,170 --> 02:39:26,600
cycle. routing loops can create network congestion,
or even bring down a network. routing protocols
1287
02:39:26,600 --> 02:39:32,310
use multiple methods to prevent routing loops
from occurring. One of the main methods that
1288
02:39:32,310 --> 02:39:39,970
they use is what's called the time to live
field for the TTL field. The TTL field keeps
1289
02:39:39,970 --> 02:39:45,710
track of how long that packet has been in
existence and how far it is traveled. And
1290
02:39:45,710 --> 02:39:52,880
after a specified amount of time or distance,
it will inform the next router to drop it.
1291
02:39:52,880 --> 02:39:59,480
This helps to prevent routing loops. That
concludes this session on the introduction
1292
02:39:59,480 --> 02:40:06,780
to router concept, part one, I talked about
the purpose of routing. And then I moved on
1293
02:40:06,780 --> 02:40:16,811
to some basic routing concepts. Hello, I'm
Brian ferrill, and welcome to peace I t's
1294
02:40:16,811 --> 02:40:23,030
session on introduction to routing concepts
part two. Today I'm going to be talking about
1295
02:40:23,030 --> 02:40:29,460
routing metrics, routing aggregation, and
then I'm going to conclude with a brief discussion
1296
02:40:29,460 --> 02:40:35,811
on high availability, we have a fair amount
of ground to cover, not a whole lot of time.
1297
02:40:35,811 --> 02:40:41,150
So let's go ahead and begin the session. Of
course, I'm going to begin by talking about
1298
02:40:41,150 --> 02:40:49,150
routing metrics. It is quite common for there
to be more than one route available to a remote
1299
02:40:49,150 --> 02:40:56,550
network. routing protocols use metrics to
determine which route is the best route to
1300
02:40:56,550 --> 02:41:02,930
reach those remote networks. Each routing
protocol will use its own set of metrics in
1301
02:41:02,930 --> 02:41:09,090
determining which routes to which networks
are placed in its routing table. The same
1302
02:41:09,090 --> 02:41:15,440
basic metric may be used by different routing
protocols. But when this occurs, the metric
1303
02:41:15,440 --> 02:41:22,830
is usually implemented in a different manner
through the use of different algorithms. The
1304
02:41:22,830 --> 02:41:29,010
first metric that we're going to discuss is
the hop count. The hop count is the number
1305
02:41:29,010 --> 02:41:37,090
of routers between two endpoints. This is
determined from the sending routers perspective,
1306
02:41:37,090 --> 02:41:44,050
the maximum transmission unit, or MTU, is
another metric that is used by routing protocols.
1307
02:41:44,050 --> 02:41:52,130
The MTU is the maximum allowed size of a packet
measured in bytes that's allowed through an
1308
02:41:52,130 --> 02:42:01,380
interface. The standard MTU for Ethernet is
1500 bytes. packets that exceed the MTU must
1309
02:42:01,380 --> 02:42:08,870
be fragmented into smaller pieces, leading
to more packets leading to a slower connection.
1310
02:42:08,870 --> 02:42:15,680
bandwidth is another common routing metric
bandwidth is a measure of the speed of the
1311
02:42:15,680 --> 02:42:22,391
network connection, the speed is commonly
measured in either kilobits per second, megabits
1312
02:42:22,391 --> 02:42:30,890
per second, or gigabits per second. Another
common metric is latency. latency is a measure
1313
02:42:30,890 --> 02:42:38,100
of time that a packet takes to traverse a
link. When latency is implemented by routing
1314
02:42:38,100 --> 02:42:45,970
protocols. The total amount of latency or
delay to go into in between two points is
1315
02:42:45,970 --> 02:42:53,311
what is used in the metric the administrative
distance, or ad as probably the most important
1316
02:42:53,311 --> 02:43:02,690
metric that's used on routers. The administrative
distance is the believability of a routing
1317
02:43:02,690 --> 02:43:09,560
protocols advertised routes, different routing
protocols are considered to be more believable,
1318
02:43:09,560 --> 02:43:16,870
or trustworthy than others. routers use the
ad to help determine which routing protocol
1319
02:43:16,870 --> 02:43:24,110
to use when more than one protocol is installed
on the router. The lowest ad of an advertised
1320
02:43:24,110 --> 02:43:30,851
route will determine the protocol that's used.
There are some common standard administrative
1321
02:43:30,851 --> 02:43:38,490
distance. First up is the directly connected
route. That's a direct link between two routers
1322
02:43:38,490 --> 02:43:46,840
that has an ad of zero in it is the most believable
or trustworthy routes. Next is the statically
1323
02:43:46,840 --> 02:43:55,729
configured route. It has an ad of one external
Border Gateway Protocol has an ad of 20. It's
1324
02:43:55,729 --> 02:44:04,760
still fairly trustworthy. Internal II II GRP
has an ad of 90 it's not as trustworthy as
1325
02:44:04,760 --> 02:44:13,360
BGP, but it is more trustworthy than OSPF
open shortest path first, which has an ad
1326
02:44:13,360 --> 02:44:24,650
of 110. i s i s has an ad of 115. So not quite
as believable as OSPF but more believable
1327
02:44:24,650 --> 02:44:35,810
than rip, which has an ad of 120. External
AIG RP has an ad of 170 in internal BGP, and
1328
02:44:35,810 --> 02:44:44,010
I've never seen internal BGP use has an ad
of 200. Now if you see an administrative distance
1329
02:44:44,010 --> 02:44:53,680
of 255 that means that that route is not believable
at all. As a side note, the ad can be set
1330
02:44:53,680 --> 02:45:00,730
by an administrator. So if you are running
both OSPF and is is on a router But you want
1331
02:45:00,730 --> 02:45:11,110
is is to be used you could actually set OSPF
ad to a higher number than is is and then
1332
02:45:11,110 --> 02:45:20,110
is is would always be used before OSPF. Now
let's move on to route aggregation. without
1333
02:45:20,110 --> 02:45:27,150
some mechanism put in place, routing tables
would soon become very large and highly inefficient.
1334
02:45:27,150 --> 02:45:33,320
through careful planning network administrator's
use a process called route aggregation to
1335
02:45:33,320 --> 02:45:40,540
condense the size of routing tables, they
do so through the use of classless inter domain
1336
02:45:40,540 --> 02:45:49,570
routing cider. To summarize routes to different
networks, route aggregation is common in networking.
1337
02:45:49,570 --> 02:45:56,460
Let's take a look at an example of Route aggregation.
Suppose we have a router that has the following
1338
02:45:56,460 --> 02:46:06,580
networks on its serial zero slash one interface.
It has 10.1 dot 1.0 slash 24 known on that
1339
02:46:06,580 --> 02:46:22,140
interface 10.1 dot 17.0 slash 24 10.1 dot
32.0 slash 24 and 10 dot 1.1 28.0 slash 24.
1340
02:46:22,140 --> 02:46:29,451
All of those networks are known to that interface
that s slash zero slash one interface. These
1341
02:46:29,451 --> 02:46:36,430
routes are what are known as contiguous routes,
they're all in line, they can be summarized
1342
02:46:36,430 --> 02:46:43,430
are aggregated by a common sider entry in
the routing table. They could all be summarized
1343
02:46:43,430 --> 02:46:53,390
by the following entry 10.1 dot 0.0 slash
16. Now there is a warning about route aggregation.
1344
02:46:53,390 --> 02:46:59,460
Route aggregation takes careful planning during
the network design phase. That above example
1345
02:46:59,460 --> 02:47:06,520
would not work if the serial interface one
slash one on that same router was connected
1346
02:47:06,520 --> 02:47:16,801
to network 10.1 dot 2.0 slash 24. Because
that new network makes those networks on on
1347
02:47:16,801 --> 02:47:23,940
the zero slash one interface, non contiguous
networks, all the known networks are no longer
1348
02:47:23,940 --> 02:47:29,660
all in a row. This leads to the fact that
the routes could no longer be aggregated or
1349
02:47:29,660 --> 02:47:37,491
summarize. Let's conclude with a discussion
on high availability. part of a network administrator's
1350
02:47:37,491 --> 02:47:44,280
job is to ensure that networks remain up and
active for the maximum amount of time. In
1351
02:47:44,280 --> 02:47:51,030
an effort to ensure that networks don't go
down. Administrators often remove single points
1352
02:47:51,030 --> 02:47:57,440
of failure. A single point of failure in a
network is the point where a single failure
1353
02:47:57,440 --> 02:48:04,530
will cause the network to cease functioning.
Network administrator's often use high availability
1354
02:48:04,530 --> 02:48:10,930
techniques in order to remove those single
points of failure. An example of a high availability
1355
02:48:10,930 --> 02:48:18,430
technique is the use of redundant links to
outside networks. Hot standby router protocol
1356
02:48:18,430 --> 02:48:29,170
hsrp is a specific example of a high availability
technique. hsrp is a proprietary Cisco method
1357
02:48:29,170 --> 02:48:35,670
of creating a fault tolerant link using two
or more routers, with connections outside
1358
02:48:35,670 --> 02:48:42,890
of the local subnet. The two routers are connected
together as well as having connections outside
1359
02:48:42,890 --> 02:48:50,250
of the local network. A virtual IP address
is created and shared between the two routers.
1360
02:48:50,250 --> 02:48:57,100
devices on the network are configured to use
that virtual IP address as their default gateway
1361
02:48:57,100 --> 02:49:02,940
for packets leaving the network. If a single
router goes down, the link outside of the
1362
02:49:02,940 --> 02:49:10,390
network is still available. Another high availability
technique is virtual router Redundancy Protocol
1363
02:49:10,390 --> 02:49:20,200
vrrp. It is an IETF Internet Engineering Task
Force standard that is similar in operation
1364
02:49:20,200 --> 02:49:28,520
to hsrp. That concludes this session on the
introduction to routing concepts. Part Two,
1365
02:49:28,520 --> 02:49:35,690
I discussed some routing metrics. Then I moved
on to route aggregation. And I concluded with
1366
02:49:35,690 --> 02:49:46,181
a brief discussion on high availability. Hello,
I'm Brian ferrill, and welcome to peace it
1367
02:49:46,181 --> 02:49:51,580
session on the introduction to routing protocols.
Today we're going to be talking about some
1368
02:49:51,580 --> 02:49:58,310
of the differences between interior and exterior
gateway routing protocols. We will introduce
1369
02:49:58,310 --> 02:50:05,770
some more routing concepts And then we will
end with routing protocols in themselves.
1370
02:50:05,770 --> 02:50:11,760
There's a whole lot of stuff to cover. So
let's go ahead and jump into this session.
1371
02:50:11,760 --> 02:50:19,850
Let's begin with the comparison between interior
and exterior gateway protocols. Interior gateway
1372
02:50:19,850 --> 02:50:28,260
protocols, or igps are a category of protocols
used within autonomy networks. Autonomous
1373
02:50:28,260 --> 02:50:34,580
networks are networks that you control or
that are under the control of a single organization.
1374
02:50:34,580 --> 02:50:45,400
The most popular IGP protocols are OSPF, open
shortest path first and rip version two. That's
1375
02:50:45,400 --> 02:50:51,630
routing information protocol version two.
Now there is a special mention here. And that's
1376
02:50:51,630 --> 02:51:01,510
is is which is intermediate system to intermediate
system is is is popular with extremely large
1377
02:51:01,510 --> 02:51:09,291
autonomous networks. Like an ISP. These are
Internet Service Providers network. Exterior
1378
02:51:09,291 --> 02:51:16,521
gateway protocols, on the other hand, are
a category of protocols used between non autonomous
1379
02:51:16,521 --> 02:51:23,520
networks. So eg peas are used between networks
that are controlled by different organizations
1380
02:51:23,520 --> 02:51:32,390
or entities. The most popular EGP protocol
is Border Gateway Protocol. No, it's not uncommon
1381
02:51:32,390 --> 02:51:38,381
for organizations to have more than one network
that they are routing traffic between. These
1382
02:51:38,381 --> 02:51:47,620
are called autonomy networks. Some IGP routing
protocols use an administrator defined autonomous
1383
02:51:47,620 --> 02:51:54,720
system number or AAS number as one means of
identifying which networks can directly communicate
1384
02:51:54,720 --> 02:52:00,850
with each other. The autonomous system number
is not a metric, but a means of identifying
1385
02:52:00,850 --> 02:52:06,960
a network that might possibly accept another
networks traffic. Something to remember is
1386
02:52:06,960 --> 02:52:14,800
that the AAS is only significant within autonomous
networks, and has no relevance outside of
1387
02:52:14,800 --> 02:52:23,800
them. Now let's move on to more routing concepts.
routing protocols can be classified by how
1388
02:52:23,800 --> 02:52:30,720
they perform thorough routing, interior gateway
and EGP. routing protocols can be broken out
1389
02:52:30,720 --> 02:52:37,200
into three other categories of protocols,
which is designated by their main method of
1390
02:52:37,200 --> 02:52:44,680
determining routes between networks. The first
class of routing protocols are distance vector
1391
02:52:44,680 --> 02:52:50,891
routing protocols. With distance vector routing
protocols, the routes are determined by how
1392
02:52:50,891 --> 02:52:57,950
many routers exist between the source and
the destination, the efficiency of the links
1393
02:52:57,950 --> 02:53:04,740
in the selected route is not taken into consideration
with distance vector protocols. Periodically,
1394
02:53:04,740 --> 02:53:11,220
the whole routing table is broadcast out onto
the network, then there are link state routing
1395
02:53:11,220 --> 02:53:18,180
protocols, metrics are used to determine the
best possible route between destinations doesn't
1396
02:53:18,180 --> 02:53:24,130
really matter how many hops there are, once
the route has been established. These protocols
1397
02:53:24,130 --> 02:53:30,460
then only monitor the state of directly connected
links and only make changes to their routing
1398
02:53:30,460 --> 02:53:37,610
tables. When changes to the links occur. With
link state routing protocols, only changes
1399
02:53:37,610 --> 02:53:44,431
in the link status are broadcasted in finally
there are hybrid routing protocols. These
1400
02:53:44,431 --> 02:53:52,920
use aspects of both the distance vector and
link state routing protocols. Let's talk about
1401
02:53:52,920 --> 02:54:01,040
the next hop. The next hop is the next router
in the path between two points. The next hop
1402
02:54:01,040 --> 02:54:08,560
is often designated by an interface address
of the device that is receiving the data or
1403
02:54:08,560 --> 02:54:16,550
by that routers name or by that routers location.
The routing table is the database table that
1404
02:54:16,550 --> 02:54:22,990
is used by a router to determine the best
possible route between two points. Different
1405
02:54:22,990 --> 02:54:29,740
routing protocols use different algorithms
to place routes in the routing table. The
1406
02:54:29,740 --> 02:54:36,691
next concept is convergence. Convergence can
be thought of as steady state. convergence
1407
02:54:36,691 --> 02:54:42,320
is measured in the amount of time that it
takes all of the routers in an autonomous
1408
02:54:42,320 --> 02:54:48,960
system to learn all of the possible routes
within that system. Faster convergence times
1409
02:54:48,960 --> 02:54:56,460
are desirable as that steady state allows
routing to occur more quickly. Now let's move
1410
02:54:56,460 --> 02:55:03,951
on to the routing protocols themselves. First
up is routing information protocol. version
1411
02:55:03,951 --> 02:55:12,040
two rip version two. Rip is an IGP distance
vector protocol. For a route to be placed
1412
02:55:12,040 --> 02:55:20,181
in the routing table, it can be no more than
15 hops away. A hop count of 16 is considered
1413
02:55:20,181 --> 02:55:27,550
unreachable. It uses various methods including
the hop count to reduce the chances of a routing
1414
02:55:27,550 --> 02:55:37,510
loop occurring. Rip version two uses multicast
address 220 4.0 dot 0.9. to advertise its
1415
02:55:37,510 --> 02:55:46,670
routing table. Open shortest path first OSPF
is the most popular IGP that's currently being
1416
02:55:46,670 --> 02:55:53,360
used. It is a link state routing protocol.
It uses the Dijkstra algorithm to determine
1417
02:55:53,360 --> 02:56:00,710
the shortest path to a network. after its
initial startup, it only advertises changes
1418
02:56:00,710 --> 02:56:07,770
to its routing table making convergence much
faster. It uses different types of link state
1419
02:56:07,770 --> 02:56:16,570
advertisements or lsats to announce different
changes or different operations. OSPF uses
1420
02:56:16,570 --> 02:56:28,190
two multicast addresses 220 4.0 dot 0.5 or
220 4.0 dot 0.6 depending upon the type of
1421
02:56:28,190 --> 02:56:37,660
LSA, that it's transmitting, next up intermediate
system to intermediate system or is is is
1422
02:56:37,660 --> 02:56:46,240
is is a link state routing protocol like OSPF
and similar to OSPF it to uses the Dijkstra
1423
02:56:46,240 --> 02:56:55,010
algorithm, but it uses different metrics to
determine the best path is is is highly scalable
1424
02:56:55,010 --> 02:57:03,101
and offers fast convergence is is is often
found within networks under the control of
1425
02:57:03,101 --> 02:57:10,351
an internet service provider. Then there's
Border Gateway Protocol BGP, it's an exterior
1426
02:57:10,351 --> 02:57:18,800
gateway protocol. That's also a hybrid routing
protocol. It is considered the routing protocol
1427
02:57:18,800 --> 02:57:26,160
of the internet. And as a hybrid protocol,
it is often considered a path vector protocol,
1428
02:57:26,160 --> 02:57:32,700
which makes it a hybrid. One of the metrics
used is the number of autonomous systems that
1429
02:57:32,700 --> 02:57:41,110
must be crossed, not individual routers, BGP
is highly scalable, but has a very slow convergence
1430
02:57:41,110 --> 02:57:48,690
time when changes do occur. As a special mention,
I'm going to talk about enhanced interior
1431
02:57:48,690 --> 02:57:57,540
gateway routing protocol, ie eigrp. It is
an advanced distance vector or hybrid IGP
1432
02:57:57,540 --> 02:58:05,720
routing protocol developed by Cisco in 2013.
Cisco made AIG RP, an open source routing
1433
02:58:05,720 --> 02:58:12,040
protocol and an effort to increase its use
in autonomous networks. It uses aspects of
1434
02:58:12,040 --> 02:58:18,420
both the distance vector protocol and the
link state protocol to build its routing table.
1435
02:58:18,420 --> 02:58:26,480
Ei GRP has a very fast convergence time. But
it's not as popular as OSPF because OSPF has
1436
02:58:26,480 --> 02:58:35,820
been open source longer than EEI GRP Ei GRP
uses a neighbor table, which is directly connected
1437
02:58:35,820 --> 02:58:42,080
routers, and a topology table to build its
routing table. The protocol only announces
1438
02:58:42,080 --> 02:58:50,750
changes to the routing table on multicast
address 224 dot 0.0 dot 10 in order to reduce
1439
02:58:50,750 --> 02:58:57,900
bandwidth consumption. That concludes this
session on the introduction to routing protocols.
1440
02:58:57,900 --> 02:59:05,690
I talked about the differences between interior
and exterior gateway protocols that I mentioned
1441
02:59:05,690 --> 02:59:15,430
some more routing concepts, and we concluded
with the routing protocols themselves. Hello,
1442
02:59:15,430 --> 02:59:23,350
I'm Brian ferrill, and welcome to pace it
session on basic elements of unified communications.
1443
02:59:23,350 --> 02:59:27,440
Today I'm going to be talking about unified
communications. And then I'm going to move
1444
02:59:27,440 --> 02:59:33,650
on to some Unified Communication concepts.
And then I'm going to end with voice over
1445
02:59:33,650 --> 02:59:40,261
IP. And with that, let's go ahead and begin
the session. Of course, I will begin this
1446
02:59:40,261 --> 02:59:47,950
session by talking about Unified Communication.
Now, unified communications is not encompassed
1447
02:59:47,950 --> 02:59:55,301
by a single product or device. It's a growing
category in the enterprise network. Unified
1448
02:59:55,301 --> 03:00:02,280
Communication or you see is the set of products
and services that Attempts to provide a consistent
1449
03:00:02,280 --> 03:00:09,660
single user interface and experience across
different media types in different devices,
1450
03:00:09,660 --> 03:00:16,500
you see allows a user to send a message from
one type of media, as in email, and have that
1451
03:00:16,500 --> 03:00:24,070
media received as a different type of media.
That email could become a text message or
1452
03:00:24,070 --> 03:00:30,990
a voicemail. So now let's talk about some
unified communication devices. First up is
1453
03:00:30,990 --> 03:00:38,200
the UCS server. These are specialized servers,
which quite often are virtual in nature that
1454
03:00:38,200 --> 03:00:45,670
are designed to implement Unified Communication
solutions in the workplace. The UC servers
1455
03:00:45,670 --> 03:00:53,150
work in conjunction with UC gateways. A UC
gateway is a network device that is designed
1456
03:00:53,150 --> 03:00:59,660
to translate between different signaling methods,
as in a voice over IP gateway, which will
1457
03:00:59,660 --> 03:01:06,860
translate an analog public switched telephone
network voice signal into a signal that can
1458
03:01:06,860 --> 03:01:13,950
be understood on The Voice network. There
are some other UC devices. any device that
1459
03:01:13,950 --> 03:01:21,660
can be used in the implementation of a unified
communication solution is considered a UC
1460
03:01:21,660 --> 03:01:29,700
device. They may include but are not limited
to voice phones, email systems, video conferencing
1461
03:01:29,700 --> 03:01:37,150
systems, and instant messaging networks. Now
let's move on to some unified communications
1462
03:01:37,150 --> 03:01:44,140
concepts. The first concept that we're going
to discuss is presence. Now presence is an
1463
03:01:44,140 --> 03:01:50,650
indicator that is used to communicate the
willingness or ability of a user to accept
1464
03:01:50,650 --> 03:02:00,080
communication. Common present statuses include
available online offline busy and do not disturb.
1465
03:02:00,080 --> 03:02:06,200
Present services are an important service
provided in UC solutions, as they will track
1466
03:02:06,200 --> 03:02:13,070
the individual users across multiple devices
and networks in real time through the use
1467
03:02:13,070 --> 03:02:21,300
of multicast transmissions. Once a communication
session has been established, multicast communication
1468
03:02:21,300 --> 03:02:28,530
is dropped in unicast network transmissions
are used. Another UCX concept that you need
1469
03:02:28,530 --> 03:02:35,100
to grasp is quality of service. Quality of
Service techniques are implemented to improve
1470
03:02:35,100 --> 03:02:42,030
Unified Communication by managing network
traffic. The most common implementation of
1471
03:02:42,030 --> 03:02:50,510
quality of service is class of service CEOs.
Seo S is a quality of service technique that's
1472
03:02:50,510 --> 03:02:57,190
used to manage network traffic by grouping
similar types of traffic and assigning a network
1473
03:02:57,190 --> 03:03:05,470
priority to that traffic. As in Unified Communication
traffic is given a higher priority than email,
1474
03:03:05,470 --> 03:03:13,600
a six bit differentiated service code point
dscp is used in the IP header to establish
1475
03:03:13,600 --> 03:03:22,320
the CEOs or class of service. Now let's move
on to voice over IP voice is one of the most
1476
03:03:22,320 --> 03:03:30,280
common implementations in a unified communications
solution. Through the use of a presence service.
1477
03:03:30,280 --> 03:03:37,880
Calls can be routed to the correct location
for where the user is out to important protocols
1478
03:03:37,880 --> 03:03:46,570
used in voiceover IP are Session Initiation
Protocol, sip, and real time Transport Protocol
1479
03:03:46,570 --> 03:03:55,040
RTP. sip has two purposes. First, it is used
to establish a communication session between
1480
03:03:55,040 --> 03:04:02,670
two endpoints. The other purpose is that once
the session is completed, sip tears down that
1481
03:04:02,670 --> 03:04:10,470
connection between the two endpoints during
the communication session RTP is used as the
1482
03:04:10,470 --> 03:04:19,840
transport call, helping to provide that quality
of service through SEO s to the endpoints.
1483
03:04:19,840 --> 03:04:26,360
Now that concludes this session on the basic
elements of Unified Communication. I talked
1484
03:04:26,360 --> 03:04:32,640
about unified communications. Then I moved
on to some Unified Communication concepts,
1485
03:04:32,640 --> 03:04:43,660
and I concluded with a brief discussion on
Voice over IP. Good day. I'm Brian ferrill,
1486
03:04:43,660 --> 03:04:50,130
and welcome to pace it session on virtualization
Technologies. Today I'm going to be discussing
1487
03:04:50,130 --> 03:04:55,790
the difference between a hypervisor in Virtual
Machine Manager, then I'm going to move on
1488
03:04:55,790 --> 03:05:00,880
to components of virtualization, and then
I'm going to have a brief demo discussion
1489
03:05:00,880 --> 03:05:07,200
on software defined networking, I have a whole
lot of information to impart not a whole lot
1490
03:05:07,200 --> 03:05:12,940
of time. So let's go ahead and begin this
session. Of course, I'm going to begin with
1491
03:05:12,940 --> 03:05:20,960
hypervisors and virtual machine managers.
So what is the difference between a hypervisor
1492
03:05:20,960 --> 03:05:26,240
in a Virtual Machine Manager, the difference
could be nothing or the difference could be
1493
03:05:26,240 --> 03:05:33,490
everything. Some people use the term hypervisor,
very broadly, they use it to refer to any
1494
03:05:33,490 --> 03:05:39,740
of the software that is used to manage virtual
machines. Others will differentiate between
1495
03:05:39,740 --> 03:05:46,670
the two terms in this way, a hypervisor does
not need a host operating system, while a
1496
03:05:46,670 --> 03:05:55,370
virtual machine manager or VMM requires a
host operating system, such as Microsoft Windows,
1497
03:05:55,370 --> 03:06:04,170
Apple OS X, or a Linux operating system. Well,
the hypervisor can operate as its own operating
1498
03:06:04,170 --> 03:06:11,490
system. With that covered, let's talk about
some of the components of virtualization.
1499
03:06:11,490 --> 03:06:18,250
First up is the virtual desktop. A virtual
desktop is a virtual machine or VM that functions
1500
03:06:18,250 --> 03:06:26,990
as a desktop. Now, any modern operating system
can be run inside of a VM desktop, multiple
1501
03:06:26,990 --> 03:06:34,390
virtual desktops may be hosted on or from
a single host system. Then there are virtual
1502
03:06:34,390 --> 03:06:41,990
servers, which surprisingly, is a virtual
machine that functions as a server. Any modern
1503
03:06:41,990 --> 03:06:48,940
server operating system can be used in a virtual
server environment. multiple virtual servers
1504
03:06:48,940 --> 03:06:55,810
may be hosted on or from a single host, guess
what there are then virtual switches, firewalls,
1505
03:06:55,810 --> 03:07:02,110
and routers. These are virtual machines that
fulfill the functions of the switch firewall
1506
03:07:02,110 --> 03:07:08,110
and router. Virtual firewalls and routers
are particularly effective when they're combined
1507
03:07:08,110 --> 03:07:15,460
with virtual network interface controllers,
or virtual NICs, and virtual switches to create
1508
03:07:15,460 --> 03:07:21,840
virtual networks. Speaking of virtual networks
an important consideration for when designing
1509
03:07:21,840 --> 03:07:28,560
a virtual network is how that virtual network
is going to pass traffic to remote networks
1510
03:07:28,560 --> 03:07:36,330
or networks outside of the host system. virtualization
by its nature leads to either an open and
1511
03:07:36,330 --> 03:07:43,360
highly scalable network or a closed self contained
system, it is possible to create a completely
1512
03:07:43,360 --> 03:07:50,979
self contained network with all of the virtual
components and never have network traffic
1513
03:07:50,979 --> 03:07:56,740
leave the host machine. But if there is a
desire or need for that network traffic to
1514
03:07:56,740 --> 03:08:03,440
pass beyond the host system, then that function
needs to be specifically granted. A connection
1515
03:08:03,440 --> 03:08:10,270
must be created between the host systems physical
neck, and the virtual networking equipment
1516
03:08:10,270 --> 03:08:18,640
to allow network traffic to pass through the
physical host system. Next up software defined
1517
03:08:18,640 --> 03:08:26,590
networking. Software Defined Networking or
SDN is the process of allowing the administration
1518
03:08:26,590 --> 03:08:34,290
and configuration of a network to be done
dynamically. With SDN, the administrator uses
1519
03:08:34,290 --> 03:08:40,890
a front end program to make adjustments to
the network. This program sends the instructions
1520
03:08:40,890 --> 03:08:47,040
to the networking equipment, which is then
reconfigured to perform as the administrator
1521
03:08:47,040 --> 03:08:54,390
desires. SDN can allow network administrators
to dynamically adjust network performance
1522
03:08:54,390 --> 03:09:01,380
without the need to log into each individual
device that needs to be adjusted to achieve
1523
03:09:01,380 --> 03:09:09,420
the desired performance. SDN is considered
to still be an emerging technology. But SDN
1524
03:09:09,420 --> 03:09:16,840
also works well for virtual networks and cloud
computing. Now, that concludes this session
1525
03:09:16,840 --> 03:09:24,430
on virtualization technology. I talked about
hypervisors and virtual machine managers.
1526
03:09:24,430 --> 03:09:31,010
Then I moved on to a brief discussion on some
components of virtualization, and I concluded
1527
03:09:31,010 --> 03:09:41,391
with another brief discussion on software
defined networking. Hello, I'm Brian ferrill,
1528
03:09:41,391 --> 03:09:48,220
and welcome to pace eyeties session on storage
area networks. Today I'm going to discuss
1529
03:09:48,220 --> 03:09:55,580
the justification for storage area networks.
And then I'm going to talk about storage area
1530
03:09:55,580 --> 03:10:02,210
network technology. And with that, let's go
ahead and begin This session, of course, I'm
1531
03:10:02,210 --> 03:10:09,660
going to begin with justifications for storage
area networks. There have been several factors
1532
03:10:09,660 --> 03:10:16,470
that have led to the increased demand for
data storage. One of them has been the dramatic
1533
03:10:16,470 --> 03:10:23,630
decrease in the actual cost of data storage,
it actually costs us less now for storage
1534
03:10:23,630 --> 03:10:30,240
on a per gigabyte basis than it has in the
past. What has happened is that as the cost
1535
03:10:30,240 --> 03:10:37,391
of storage has decreased, the demand for storage
has increased dramatically. Businesses are
1536
03:10:37,391 --> 03:10:43,840
now generating and analyzing huge amounts
of data in an effort to create a competitive
1537
03:10:43,840 --> 03:10:50,220
advantage. Think Big Data, I'm sure you've
heard about big data recently, or this increase
1538
03:10:50,220 --> 03:10:57,470
in data collection has led to an increased
demand for storage capacity. Another factor
1539
03:10:57,470 --> 03:11:04,390
is that as the demand for data has increased,
it is needed to be more available, which means
1540
03:11:04,390 --> 03:11:10,500
that there has been a need to be able to access
that data from anywhere in the accessibility
1541
03:11:10,500 --> 03:11:17,300
as needed to be increased as well, including
from non standard devices. A storage area
1542
03:11:17,300 --> 03:11:26,150
network or sand can be a solution to the need
for both storage capacity, and high availability.
1543
03:11:26,150 --> 03:11:33,160
There are several advantages to the storage
area network. First off is scalability, the
1544
03:11:33,160 --> 03:11:39,950
amount of data that is being generated today
is huge. This has led to a need to store that
1545
03:11:39,950 --> 03:11:46,400
data, the sin is more scalable than other
options. As your storage needs increase, the
1546
03:11:46,400 --> 03:11:53,100
capacity of the sin can be easily increased
to meet that storage need. Then there's data
1547
03:11:53,100 --> 03:11:59,510
availability, the demand has also increased
for that data to be available at any time
1548
03:11:59,510 --> 03:12:05,870
from anywhere. And a sand can play a vital
role in creating that accessibility. One of
1549
03:12:05,870 --> 03:12:12,950
the most popular implementations of a sand
is to deploy it as part of a cloud computing
1550
03:12:12,950 --> 03:12:20,410
solution. This increases the availability
of that data that's being stored on the sand.
1551
03:12:20,410 --> 03:12:26,439
And finally, there's optimization. As the
requirements to store data are removed from
1552
03:12:26,439 --> 03:12:33,440
application servers, those servers can then
be optimized to run those applications much
1553
03:12:33,440 --> 03:12:41,360
more efficiently. At the same time, data storage
is also optimized. It's time now to discuss
1554
03:12:41,360 --> 03:12:49,260
some sand technology. The storage area network
or sand, and the network attached storage
1555
03:12:49,260 --> 03:12:56,729
or NAS often get confused with one another,
but they are different. The sin is an actual
1556
03:12:56,729 --> 03:13:03,190
network of devices that have the sole purpose
of storing data efficiently. On the other
1557
03:13:03,190 --> 03:13:10,030
hand, the NAS is a specifically designed network
appliance that has been configured to store
1558
03:13:10,030 --> 03:13:17,080
data more efficiently than standard storage
methods. The difference is that a NAS is a
1559
03:13:17,080 --> 03:13:23,220
data storage appliance that is placed on a
network. Well as San is a network of data
1560
03:13:23,220 --> 03:13:31,940
storage devices. It is not uncommon for a
San to contain multiple NAS devices. With
1561
03:13:31,940 --> 03:13:37,830
all of that data storage capabilities, several
technologies have been developed to ease the
1562
03:13:37,830 --> 03:13:43,871
transmission of that data. The first one that
we're going to discuss is fiber channel, or
1563
03:13:43,871 --> 03:13:51,760
FC fiber channel is a high speed network technology
that was originally developed to operate over
1564
03:13:51,760 --> 03:13:57,939
fiber optic cables only. since its introduction,
the standards have been modified to allow
1565
03:13:57,939 --> 03:14:04,650
the use of copper cabling, in conjunction
with fiber optic cabling. fiber channel is
1566
03:14:04,650 --> 03:14:12,600
commonly used to connect to sands. When Fibre
Channel is implemented. It uses the Fibre
1567
03:14:12,600 --> 03:14:21,640
Channel protocol RF CP, as its transport protocol
to transmit scuzzy commands, so it transmits
1568
03:14:21,640 --> 03:14:29,560
small computer system interface commands to
storage devices, as in the NAS appliances,
1569
03:14:29,560 --> 03:14:38,150
so a sin implements FCP as opposed to TCP
as its Transport Protocol when Fibre Channel
1570
03:14:38,150 --> 03:14:45,729
is used. Another technology that was developed
was internet scuzzy, or I scuzzy, I scuzzy
1571
03:14:45,729 --> 03:14:52,240
is an IP based networking standard that is
used to connect data storage facilities in
1572
03:14:52,240 --> 03:14:59,721
sans. I scuzzy allows for scuzzy commands
and processes to take place over longer distances.
1573
03:14:59,721 --> 03:15:08,771
Then the original scuzzy implementation, jumbo
frames are also allowed within the San environment.
1574
03:15:08,771 --> 03:15:15,400
jumbo frames allow for greater throughput
of data by allowing up to 9000 bytes of data
1575
03:15:15,400 --> 03:15:22,521
to be in a single frame. This can greatly
increase the efficiency of a sin. As a comparison,
1576
03:15:22,521 --> 03:15:30,880
the standard frame on an Ethernet network,
it can only be a maximum of 1500 bytes. Now
1577
03:15:30,880 --> 03:15:37,430
that concludes this session on storage area
networks. I talked about the justification
1578
03:15:37,430 --> 03:15:45,870
for storage area networks, and then I concluded
with a brief discussion on some sand technology.
1579
03:15:45,870 --> 03:15:56,110
Hello, I'm Brian ferrill, and welcome to pace
it session on basic cloud concepts. Today,
1580
03:15:56,110 --> 03:16:02,600
we're going to be talking about cloud classifications.
And then we will conclude with different types
1581
03:16:02,600 --> 03:16:08,350
of cloud computing. There's a fair amount
of information to cover. So let's go ahead
1582
03:16:08,350 --> 03:16:17,150
and dive right in. I will begin our session
with a discussion about cloud classifications.
1583
03:16:17,150 --> 03:16:24,140
Cloud computing is where the resources on
the network are not actually physical in nature,
1584
03:16:24,140 --> 03:16:30,970
they are provided to the end user. Virtually,
cloud computing can lead to a very fluid and
1585
03:16:30,970 --> 03:16:37,680
dynamic environment, as the required resources
are normally only provisioned or supplied
1586
03:16:37,680 --> 03:16:44,501
as needed, and are decommission or shut down
once their use is done. Most often. These
1587
03:16:44,501 --> 03:16:51,530
virtual resources are not owned by the company
or user that uses them, but are provided by
1588
03:16:51,530 --> 03:16:58,330
a service provider. While cloud computing
is highly configurable and changeable, it
1589
03:16:58,330 --> 03:17:04,689
does have some basic structures that are used
in the classification of the type of cloud
1590
03:17:04,689 --> 03:17:10,720
that is in use. The first classification of
cloud computing that we're going to talk about
1591
03:17:10,720 --> 03:17:18,290
is the public cloud. This is where systems
can interact with services, and devices within
1592
03:17:18,290 --> 03:17:24,580
the public cloud and on public networks, like
over the Internet, and possibly with other
1593
03:17:24,580 --> 03:17:32,250
public clouds. The public cloud is where the
services that are provided are not just provided
1594
03:17:32,250 --> 03:17:38,930
to a specific user, but are open for the public
to purchase in use, then there are private
1595
03:17:38,930 --> 03:17:46,810
clouds. This is where system only communicate
with services and devices within a specific
1596
03:17:46,810 --> 03:17:54,130
private cloud. A private cloud is essentially
just that private. The only users who have
1597
03:17:54,130 --> 03:18:00,730
access to it are ones who are authorized to
use it. The cloud classification can be hybrid,
1598
03:18:00,730 --> 03:18:06,600
it can combine aspects of both the public
and private clouds. And last up, there are
1599
03:18:06,600 --> 03:18:13,680
community clouds. This is where cloud services
are used by private individuals, organizations
1600
03:18:13,680 --> 03:18:21,010
or groups that have a common interest. Now
let's move on to different types of cloud
1601
03:18:21,010 --> 03:18:27,100
computing. Because of the nature of cloud
computing, it is very configurable to the
1602
03:18:27,100 --> 03:18:33,520
needs and desires of the purchaser of the
cloud services. purchasers have many options
1603
03:18:33,520 --> 03:18:39,200
beyond the type of cloud services that they
want to provision, they must also determine
1604
03:18:39,200 --> 03:18:45,270
what type of service they are going to require.
From the most basic of services to the most
1605
03:18:45,270 --> 03:18:52,080
highly complex of services, the purchaser
needs to have a plan going into Cloud computing,
1606
03:18:52,080 --> 03:18:57,900
in order for it to be efficient and effective
for them. So now let's move on to some of
1607
03:18:57,900 --> 03:19:05,561
those services that cloud computing can offer.
First up is Software as a Service. The End
1608
03:19:05,561 --> 03:19:12,290
User purchases the rights to use an application
or software without the need to configure
1609
03:19:12,290 --> 03:19:17,790
the virtual servers that will deliver the
application to them. It is usually delivered
1610
03:19:17,790 --> 03:19:25,271
as a web app or web application, open the
news from within a web browser. But not always.
1611
03:19:25,271 --> 03:19:35,010
If you have a subscription to Microsoft Office
365 you are utilizing software as a service.
1612
03:19:35,010 --> 03:19:43,160
Then there is platform as a service or P as
the user is provided with a development platform
1613
03:19:43,160 --> 03:19:48,380
for the creation of software packages without
the need to configure the virtual servers
1614
03:19:48,380 --> 03:19:55,200
and the infrastructure that delivers it. You
are essentially renting server or computing
1615
03:19:55,200 --> 03:20:04,729
power in order to develop your software packages.
Pa is more complex than software as a service.
1616
03:20:04,729 --> 03:20:11,110
In Finally we have Infrastructure as a Service.
This is where the end user is provided with
1617
03:20:11,110 --> 03:20:18,971
access to virtual servers configurable by
the customer, and other virtual network resources,
1618
03:20:18,971 --> 03:20:25,560
their infrastructure is actually virtually
provided to them. This creates a highly configurable
1619
03:20:25,560 --> 03:20:31,630
environment in which customers can create
the resources and the performance that they
1620
03:20:31,630 --> 03:20:39,350
require. The End User supplies the software
that's going to be used on the IaaS network,
1621
03:20:39,350 --> 03:20:46,641
or they purchase it as an additional software
as a service service. As you could have guessed
1622
03:20:46,641 --> 03:20:52,670
from that last statement, it's not uncommon
for the type of cloud computing being utilized
1623
03:20:52,670 --> 03:21:00,500
by an organization to be a mix. Some departments
may rely upon in use Infrastructure as a Service.
1624
03:21:00,500 --> 03:21:06,979
While the development team will only utilize
a platform as a service service. Part of the
1625
03:21:06,979 --> 03:21:14,580
advantage of cloud computing is that the purchaser
only needs to initialize and pay for resources
1626
03:21:14,580 --> 03:21:21,120
as they are needed. In a private cloud situation,
it is possible for an organization that is
1627
03:21:21,120 --> 03:21:26,950
using it to actually own the cloud resources.
If they do own the cloud resources, they may
1628
03:21:26,950 --> 03:21:35,280
have it on site, or they may pay to have those
resources hosted off site. That way they can
1629
03:21:35,280 --> 03:21:42,020
offload the maintenance cost of maintaining
those resources. Now, that concludes this
1630
03:21:42,020 --> 03:21:49,500
session on basic cloud concepts. I talked
about different cloud classifications. And
1631
03:21:49,500 --> 03:21:59,540
then I concluded with a brief discussion on
types of cloud computing. Good day, I'm Brian
1632
03:21:59,540 --> 03:22:06,270
ferrill, and welcome to peace I t's session
on implementing a basic network. Today we're
1633
03:22:06,270 --> 03:22:12,729
going to discuss plan the network and then
configure the network. There's a fair amount
1634
03:22:12,729 --> 03:22:19,000
of ground to cover. So let's go ahead and
dive into this session. Of course, I'm going
1635
03:22:19,000 --> 03:22:26,260
to begin with plan the network. So you need
a simple small office home office network,
1636
03:22:26,260 --> 03:22:34,110
Craig just plugged two PCs into a single hub,
and you have a very basic network. But does
1637
03:22:34,110 --> 03:22:40,689
it achieve what you want? How do you know
if you don't have a plan? A network plan is
1638
03:22:40,689 --> 03:22:48,520
vital when implementing any network more complicated
than the most very basic of networks. That
1639
03:22:48,520 --> 03:22:55,560
plan should cover what you are hoping to achieve
and how you are going to get there. In addition
1640
03:22:55,560 --> 03:23:02,420
to your expertise, you are also going to need
input from your end users. Nothing is quite
1641
03:23:02,420 --> 03:23:08,550
so frustrating as delivering the network that
you've planned and built, and having the customer
1642
03:23:08,550 --> 03:23:15,920
tell you that it is not what they wanted,
or needed. Let's talk about that network plan
1643
03:23:15,920 --> 03:23:22,890
in a little bit more detail. The first thing
that you should do is create a list of requirements.
1644
03:23:22,890 --> 03:23:27,880
Now in order to make that list, you need to
define why the network is needed. That will
1645
03:23:27,880 --> 03:23:34,650
help you to define what network features are
required, then you need to define the scope
1646
03:23:34,650 --> 03:23:41,810
or size of the network. Once you have those,
they will help to establish a budget to implement
1647
03:23:41,810 --> 03:23:48,160
that network. Once you know why the network
is needed, and what features are required
1648
03:23:48,160 --> 03:23:54,250
then you can work on network design. In network
design, you need to determine what equipment
1649
03:23:54,250 --> 03:24:00,000
is needed to implement that network. Part
of the design is also how the network will
1650
03:24:00,000 --> 03:24:06,660
be organized and how shared resources will
be placed on the network. When you're planning
1651
03:24:06,660 --> 03:24:12,090
the network something that you should also
consider are compatibility issues. You need
1652
03:24:12,090 --> 03:24:19,360
to know what standards are in use now in what
standards will there be in the future. Included
1653
03:24:19,360 --> 03:24:25,450
in those compatibility issues our does any
current equipment that is required, needs
1654
03:24:25,450 --> 03:24:32,060
specific cabling or connectors in order to
be installed. That is something that often
1655
03:24:32,060 --> 03:24:38,900
gets overlooked. Your network plan also needs
to deal with network cabling runs your internal
1656
03:24:38,900 --> 03:24:45,120
connections, how many node connections will
be required and where How will you plan for
1657
03:24:45,120 --> 03:24:51,290
future expansion? that future expansion is
more than likely going to require more internal
1658
03:24:51,290 --> 03:24:57,220
connections you should build in some tolerance
for future expansion. Then you need to consider
1659
03:24:57,220 --> 03:25:03,450
external connections. How will the network
connect to the outside. Where will that when
1660
03:25:03,450 --> 03:25:09,150
connection come into your building? And where
will your equipment be placed so that it can
1661
03:25:09,150 --> 03:25:15,410
reach those wind connections. That is also
part of the network equipment placement plan.
1662
03:25:15,410 --> 03:25:20,470
Part of that plan also needs to consider if
there is a wiring or equipment closet and
1663
03:25:20,470 --> 03:25:26,100
where it's going to be located. If you do
have a wiring or equipment closet, are there
1664
03:25:26,100 --> 03:25:31,790
environmental considerations about placing
the equipment in there? Is it too hot? Is
1665
03:25:31,790 --> 03:25:36,960
it too cold? Is it too humid? Or is it too
dry? You need to think about those things
1666
03:25:36,960 --> 03:25:43,040
when you're placing your network equipment.
Your plan should also cover how network security
1667
03:25:43,040 --> 03:25:48,920
will be implemented. Are there specific types
of firewall emplacement considerations for
1668
03:25:48,920 --> 03:25:56,840
those firewalls? Will virtual local area networks
be required? And if so, how many? Also, how
1669
03:25:56,840 --> 03:26:04,630
will your switch port security be implemented?
All of these go into a successful network
1670
03:26:04,630 --> 03:26:11,710
plan. Now let's talk about configuring the
network. Here are some network configuration
1671
03:26:11,710 --> 03:26:19,430
considerations for you. First up, how will
your clients receive their internet protocol
1672
03:26:19,430 --> 03:26:26,450
addresses their IP addresses, using static
IP address configuration creates a higher
1673
03:26:26,450 --> 03:26:33,460
level of security. But it's harder to manage,
you could use Dynamic Host Configuration Protocol
1674
03:26:33,460 --> 03:26:42,080
DHCP to automatically assign IP addresses
from a pre configured pool. But your security
1675
03:26:42,080 --> 03:26:49,240
may be a little bit lower If you do so, if
you do use DHCP, you might want to consider
1676
03:26:49,240 --> 03:26:56,140
using MAC filtering. MAC filtering will only
allow specified MAC addresses that physical
1677
03:26:56,140 --> 03:27:01,600
burned in address onto the network. It is
an effective security measure that kind of
1678
03:27:01,600 --> 03:27:07,811
like static IP addressing, it can be difficult
to control and manage especially as the network
1679
03:27:07,811 --> 03:27:13,540
grows. Something else to consider is that
if a server will be hosted on the network
1680
03:27:13,540 --> 03:27:19,140
that needs to be accessed from outside of
that network, as in you're hosting a web server,
1681
03:27:19,140 --> 03:27:27,000
then you're going to need a demilitarized
zone a DMZ. the DMZ is an area of the network
1682
03:27:27,000 --> 03:27:32,811
in which outside connections are allowed.
While the internal network remains protected
1683
03:27:32,811 --> 03:27:39,790
from that outside traffic. A DMZ will require
a custom configuration of the firewall. In
1684
03:27:39,790 --> 03:27:47,910
most implementations, two firewalls are used.
But it's not necessary to use two firewalls.
1685
03:27:47,910 --> 03:27:54,100
Talking about firewalls, firewall placement
and configuration considerations. Our next
1686
03:27:54,100 --> 03:28:02,630
most small office home office when connection
devices, as in their cable modems or DSL modems
1687
03:28:02,630 --> 03:28:09,280
include firewall services that are sufficient
in most cases for those small simple networks.
1688
03:28:09,280 --> 03:28:15,280
But if a DMZ needs to be deployed, the best
method is to introduce an additional router
1689
03:28:15,280 --> 03:28:21,590
in firewall into the network with the DMZ
residing between the wind equipment, and the
1690
03:28:21,590 --> 03:28:29,170
new router firewall combination. Another aspect
of deploying a DMZ is that port forwarding
1691
03:28:29,170 --> 03:28:37,090
should also be used at the router firewall
level. Port Forwarding is used to direct requests
1692
03:28:37,090 --> 03:28:45,430
for specific resources, like a request for
a web page to the computer that has the resource.
1693
03:28:45,430 --> 03:28:52,189
Let's move on to wireless network configuration
considerations. The first thing to consider
1694
03:28:52,189 --> 03:28:58,660
in a wireless network is the name of the wireless
network. That's the service set identifier,
1695
03:28:58,660 --> 03:29:07,260
the SSID. Now the SSID can be set to broadcast
in the clear. Alternatively, the SSID can
1696
03:29:07,260 --> 03:29:13,740
be set for the broadcast to be hidden. Some
people consider hiding the SSID broadcast
1697
03:29:13,740 --> 03:29:19,750
as a security measure. But it really doesn't
work that way. It doesn't stop the broadcast.
1698
03:29:19,750 --> 03:29:26,721
It only hides the broadcast. A packet sniffer
can easily see those broadcasts and those
1699
03:29:26,721 --> 03:29:33,970
broadcast packets can be easily interpreted.
So hiding the SSID is not an effective security
1700
03:29:33,970 --> 03:29:40,090
measure. But it does make things a little
bit more difficult. The next aspect of wireless
1701
03:29:40,090 --> 03:29:45,870
network configuration that you need to consider
is encryption. First off, I will say you need
1702
03:29:45,870 --> 03:29:52,520
to have encryption on your wireless network.
Not only that, but you need to turn it on.
1703
03:29:52,520 --> 03:29:59,340
By default wireless routers and wireless access
points why apps do not have encryption enable
1704
03:29:59,340 --> 03:30:09,141
it Add the minimum. Your encryption type should
be WPA to personal. That's at the minimum.
1705
03:30:09,141 --> 03:30:14,730
Some wireless network equipment comes with
a service that is called why five Protected
1706
03:30:14,730 --> 03:30:22,150
Setup, WPS. And if it does, it's enabled by
default, this should be turned off and not
1707
03:30:22,150 --> 03:30:29,060
used as it creates a weakness in the wireless
network. Why is that? Well, because WPS can
1708
03:30:29,060 --> 03:30:36,439
be easily exploited by an attacker, the network
that you implement may not be exactly what
1709
03:30:36,439 --> 03:30:43,560
you planned. So document any changes to the
plan. undoubtably, during the process of implementing
1710
03:30:43,560 --> 03:30:50,180
that plan, some changes will be introduced
some by you in some by request of the end
1711
03:30:50,180 --> 03:30:57,830
user. Always document those changes to the
plan and have the end user sign off on them,
1712
03:30:57,830 --> 03:31:04,460
then be sure to incorporate those changes
into the final network documentation. Now,
1713
03:31:04,460 --> 03:31:11,880
that concludes this session on implementing
a basic network. I talked about plan the network,
1714
03:31:11,880 --> 03:31:20,729
and then I talked about configure the network.
Good day. I'm Brian ferrill. And welcome to
1715
03:31:20,729 --> 03:31:28,150
pace I t's session on analyzing monitoring
reports. Today I'm going to talk about baseline
1716
03:31:28,150 --> 03:31:33,080
reports. And then I'm going to move on to
just reports in general, I have a fair amount
1717
03:31:33,080 --> 03:31:39,640
of ground to cover not a whole lot of time.
So let's go ahead and jump into this session.
1718
03:31:39,640 --> 03:31:45,970
And of course, I'm going to begin by talking
about baselines. How do you know what constitutes
1719
03:31:45,970 --> 03:31:52,061
good network performance and what indicates
that an issue is about to happen. This is
1720
03:31:52,061 --> 03:31:58,850
where baseline documentation comes into play.
baseline documentation provides a snapshot
1721
03:31:58,850 --> 03:32:05,420
of the network when it is running efficiently,
at least hopefully, when it's running efficiently.
1722
03:32:05,420 --> 03:32:11,840
baselines are usually kept as a log file.
At the minimum baselines should be established
1723
03:32:11,840 --> 03:32:19,300
on CPU utilization, and network bandwidth
utilization. You may also base Mark other
1724
03:32:19,300 --> 03:32:25,710
functions as you deem them to be relevant.
network administrators should perform periodic
1725
03:32:25,710 --> 03:32:32,540
tests against the baseline to check to see
if the baseline is changed, they will change
1726
03:32:32,540 --> 03:32:38,170
over time. And in order for network administrators
to know what constitutes good performance
1727
03:32:38,170 --> 03:32:43,550
on their network, their baselines need to
be current, you can use Windows performance
1728
03:32:43,550 --> 03:32:50,250
monitor to help establish the baselines for
your network. Let's talk about some of the
1729
03:32:50,250 --> 03:32:59,190
items that should be considered for baseline
reports. First up is network device CPU utilization.
1730
03:32:59,190 --> 03:33:05,320
Knowing the CPU utilization on a piece of
equipment can help to determine when a network
1731
03:33:05,320 --> 03:33:13,170
device is going to fail. If your CPU utilization
is constantly at 100%, you know, there's a
1732
03:33:13,170 --> 03:33:17,940
problem. That problem may be that it's going
to fail. Or it may be that you need to install
1733
03:33:17,940 --> 03:33:23,439
more network devices to take care of a growing
network. But you won't really know that if
1734
03:33:23,439 --> 03:33:31,270
you're not baselining the CPU utilization
network device memory utilization should also
1735
03:33:31,270 --> 03:33:37,670
be baseline. It can help to determine when
it is time to expand the memory of a network
1736
03:33:37,670 --> 03:33:44,330
device. A good item for baselining is bandwidth
utilization. This can help to determine the
1737
03:33:44,330 --> 03:33:50,290
overall health of a network, it can help to
determine when network segmentation should
1738
03:33:50,290 --> 03:33:56,790
occur. It can also help to determine if a
network device is about to fail, particularly
1739
03:33:56,790 --> 03:34:03,930
if it's creating a storm of data. baseline
utilization reports can help identifying when
1740
03:34:03,930 --> 03:34:10,120
a security breach has occurred, you might
want to consider baselining your storage device
1741
03:34:10,120 --> 03:34:15,810
utilization This can help to determine when
storage utilization has become a bottleneck
1742
03:34:15,810 --> 03:34:20,979
on the network, where your storage devices
actually causing the network to slow down
1743
03:34:20,979 --> 03:34:25,560
because there's too much data being pushed
into it. Which means that baselining your
1744
03:34:25,560 --> 03:34:32,420
storage utilization can help determine when
to increase the storage capacity of that network.
1745
03:34:32,420 --> 03:34:38,890
You might also want to baseline your wireless
channel utilization. This can help to determine
1746
03:34:38,890 --> 03:34:45,040
how saturated the wireless channels have become.
Once it's been determined that your wireless
1747
03:34:45,040 --> 03:34:51,620
channels are saturated, a new wireless access
point can be installed to alleviate the pressure
1748
03:34:51,620 --> 03:34:57,560
and then you need to create a new baseline
for wireless channel utilization. This baseline
1749
03:34:57,560 --> 03:35:04,390
can also help to determine if there is unauthorized
wireless access occurring on your wireless
1750
03:35:04,390 --> 03:35:09,840
network, especially if there is utilization
on a channel that is not supposed to have
1751
03:35:09,840 --> 03:35:18,250
any utilization. Now let's move on to analyzing
reports. Before we talk about analyzing reports,
1752
03:35:18,250 --> 03:35:25,250
let's talk about log file management. log
files can accumulate data quickly. And unfortunately,
1753
03:35:25,250 --> 03:35:32,010
some administrators only review log files
after a major problem has occurred. In most
1754
03:35:32,010 --> 03:35:38,670
situations, this is a case of too much information
at the wrong time. Good administrators will
1755
03:35:38,670 --> 03:35:44,750
set the proper reporting levels with their
logging software, they won't be logging all
1756
03:35:44,750 --> 03:35:51,590
that debug information that level seven information,
unless of course, they're actively debugging
1757
03:35:51,590 --> 03:35:58,280
a system or application. Good administrators
will review log files and compare them against
1758
03:35:58,280 --> 03:36:04,061
their baseline documentation. They do this
to find issues while the issues are still
1759
03:36:04,061 --> 03:36:11,360
minor and before they become major. log files
should also be kept and archived in case there
1760
03:36:11,360 --> 03:36:16,979
is a need for historical data. When you do
archive your log files, you should follow
1761
03:36:16,979 --> 03:36:23,760
the organization's data storage policy. something
to consider is that you may want to create
1762
03:36:23,760 --> 03:36:29,950
running graphs of important metrics that are
captured by log files. graphing the data gives
1763
03:36:29,950 --> 03:36:36,729
a quick visual reference making it easier
to spot issues and trends. Many logging applications
1764
03:36:36,729 --> 03:36:42,790
give the administrator the option of creating
those graphs easily and quickly. But then
1765
03:36:42,790 --> 03:36:49,241
again, they don't do you any good if you don't
review them on a regular basis. If you're
1766
03:36:49,241 --> 03:36:54,261
having an issue with a router or link, one
of the first things that you want to do is
1767
03:36:54,261 --> 03:37:00,280
you want to run an interface report. Now when
you're reviewing the output from the interface
1768
03:37:00,280 --> 03:37:06,500
report, the first line is usually a report
on the status of the link or that interface.
1769
03:37:06,500 --> 03:37:12,301
If it says something like Fast Ethernet is
up line protocol is up that's all good. That
1770
03:37:12,301 --> 03:37:17,900
means that interface is up and active and
a link has been established. If it says Fast
1771
03:37:17,900 --> 03:37:25,600
Ethernet zero slash zero is up line protocol
is down, guess what all is not good. The interface
1772
03:37:25,600 --> 03:37:31,460
is administratively set up, but it is not
able to communicate with the other end of
1773
03:37:31,460 --> 03:37:36,511
the link. And there are several different
issues that may be the cause there. If that
1774
03:37:36,511 --> 03:37:44,000
first line says Fast Ethernet zero slash zero
is down line protocol is up all is not good.
1775
03:37:44,000 --> 03:37:50,170
This down up status indicates that there is
an issue on your end of the connection. In
1776
03:37:50,170 --> 03:37:56,570
most cases, that's going to be a cable issue
or with the physical port itself. In your
1777
03:37:56,570 --> 03:38:04,260
final status option is Fast Ethernet is down
line protocol is down. If you see that all
1778
03:38:04,260 --> 03:38:10,521
is not good. But also all is not bad, at least
not yet. The issue here is that the interface
1779
03:38:10,521 --> 03:38:16,689
has been administratively shut down. If you
want that interface up, you need to issue
1780
03:38:16,689 --> 03:38:21,740
the command to bring that interface up and
then check the status report again. If the
1781
03:38:21,740 --> 03:38:27,910
link status of the interface indicates that
there are no problems, as in it's in an up
1782
03:38:27,910 --> 03:38:33,590
in up state, but something is not operating
correctly, then it's time to dig a little
1783
03:38:33,590 --> 03:38:39,120
bit deeper into that interface monitoring
report. There are a lot of things that can
1784
03:38:39,120 --> 03:38:45,460
happen on a network devices interface to cause
issues. In most cases, you will be required
1785
03:38:45,460 --> 03:38:51,979
to log into the device and run the device's
report to determine the cause of any problems
1786
03:38:51,979 --> 03:38:57,290
on that interface. One of the main culprits
for creating an issue on an interface are
1787
03:38:57,290 --> 03:39:04,080
speed and duplex settings. If there is a speed
mismatch, the devices will not connect. And
1788
03:39:04,080 --> 03:39:10,550
it's highly likely that your status will be
in an up line protocol down state. If a duplex
1789
03:39:10,550 --> 03:39:17,110
mismatch has occurred. This will cause intermittent
issues, you will need to look at the errors
1790
03:39:17,110 --> 03:39:23,690
counter in the output or input reports. You
also need to look at the counter for dropped
1791
03:39:23,690 --> 03:39:30,050
packets. If the device is discarding incoming
packets, then more than likely the device's
1792
03:39:30,050 --> 03:39:36,181
CPU is being over utilized. So you may need
another device or that device is about to
1793
03:39:36,181 --> 03:39:43,000
fail. If the device is dropping outgoing packets,
then there is a bandwidth congestion issue
1794
03:39:43,000 --> 03:39:49,110
on that interface. If the interface resets
counter keeps going up, that means that the
1795
03:39:49,110 --> 03:39:55,390
interface keeps resetting itself, the most
likely cause is a communications issue between
1796
03:39:55,390 --> 03:40:02,910
the two endpoints that's forcing that interface
to reset Now that concludes this session on
1797
03:40:02,910 --> 03:40:10,070
analyzing monitoring reports. I briefly talked
about baseline reports. And then I moved on
1798
03:40:10,070 --> 03:40:18,811
to other reports that you should be analyzing
to take care of problems before they occur.
1799
03:40:18,811 --> 03:40:26,530
Hello, I'm Brian ferrill. And welcome to peace
I t's session on network monitoring, part
1800
03:40:26,530 --> 03:40:31,320
one. Today we're going to be talking about
the why of monitoring. And then we're going
1801
03:40:31,320 --> 03:40:36,689
to talk about tools to monitor the network.
There's a fair amount of ground to cover.
1802
03:40:36,689 --> 03:40:44,400
So let's go ahead and jump into this session.
I'm going to begin with the why of network
1803
03:40:44,400 --> 03:40:50,870
monitoring. How do you know what is going
on in your network? Is it healthy? Or is it
1804
03:40:50,870 --> 03:40:58,540
about to crash? network administrator's really
hate to be surprised by failures in their
1805
03:40:58,540 --> 03:41:05,330
networks, especially ones that could have
been foreseen and therefore kept from happening?
1806
03:41:05,330 --> 03:41:11,730
How do they keep from being surprised? Well,
they enact a plethora of procedures and tools
1807
03:41:11,730 --> 03:41:18,460
to monitor their networks. And to keep track
of how those networks are behaving. They do
1808
03:41:18,460 --> 03:41:25,740
this to reduce the surprise element. Now that
we've covered the why of network monitoring,
1809
03:41:25,740 --> 03:41:32,260
let's talk about tools that you can use to
monitor the network. One of the main tools
1810
03:41:32,260 --> 03:41:39,310
that network administrators use to monitor
their networks are log files. all operating
1811
03:41:39,310 --> 03:41:44,990
systems offer a means of viewing events that
occurred to that specific machine. That also
1812
03:41:44,990 --> 03:41:51,200
includes networking equipment. There have
been some applications that have been developed
1813
03:41:51,200 --> 03:41:57,610
to monitor systems and networks that also
generate log files, among other actions that
1814
03:41:57,610 --> 03:42:03,610
they can take. log files can be used to help
pinpoint when a problem occurred, and help
1815
03:42:03,610 --> 03:42:10,290
narrow down the possible causes of that problem.
log files can also be used to help create
1816
03:42:10,290 --> 03:42:16,930
a baseline of network behavior so that you
know what to expect from your network. log
1817
03:42:16,930 --> 03:42:23,760
files can usually be classified as being systems
logs, General logs, or history logs. As a
1818
03:42:23,760 --> 03:42:29,642
general rule, log files are an after the fact
means of monitoring the network, and they're
1819
03:42:29,642 --> 03:42:36,990
not very good at real time analysis. That's
partially due to the sheer amount of information
1820
03:42:36,990 --> 03:42:43,810
that log files can generate. It's just too
difficult to keep track of that in real time.
1821
03:42:43,810 --> 03:42:49,471
Now let's talk about some specific logging
tools that you can use. The first one that
1822
03:42:49,471 --> 03:42:55,590
I'm going to talk about is Event Viewer. It's
not really a log file in itself. It comes
1823
03:42:55,590 --> 03:43:02,880
with Windows Server in most other Windows
operating systems, and this tool can be used
1824
03:43:02,880 --> 03:43:10,560
to review windows log files. The most important
log files that you can view from Event Viewer
1825
03:43:10,560 --> 03:43:17,300
are application security and systems logs.
Application logs containing events that are
1826
03:43:17,300 --> 03:43:23,660
triggered by the actions of an application.
For example, if you have live update enabled,
1827
03:43:23,660 --> 03:43:31,101
it will create log entries based on actions
taken by live update. Then there are security
1828
03:43:31,101 --> 03:43:37,090
logs. These contain events that are triggered
by security events. For example, some logs
1829
03:43:37,090 --> 03:43:44,720
are created for successful and unsuccessful
logon attempts. Then there are systems logs.
1830
03:43:44,720 --> 03:43:50,400
These contain events triggered by Windows
systems components, for example, it will create
1831
03:43:50,400 --> 03:43:58,060
an entry for when a driver starts or fails
to start in either situation in log entry
1832
03:43:58,060 --> 03:44:06,950
will be created. Now let's talk about a non
Microsoft log. And that would be syslog. syslog,
1833
03:44:06,950 --> 03:44:12,689
was developed in the 1980s. And it provides
devices that normally would not be able to
1834
03:44:12,689 --> 03:44:20,760
communicate with a means of delivering performance
and problem information to systems administrators.
1835
03:44:20,760 --> 03:44:26,130
This permits there to be separation between
the software that generates the message, the
1836
03:44:26,130 --> 03:44:33,080
storage of that message in the software that
analyzes the generated message. This separation
1837
03:44:33,080 --> 03:44:39,420
of function allows syslog to be highly configurable,
and this allowed it to continue to be a vital
1838
03:44:39,420 --> 03:44:46,410
tool for monitoring networks, even today.
As a matter of fact, the Internet Engineering
1839
03:44:46,410 --> 03:44:55,740
Task Force the IETF, like syslog so much that
they standardized it in 2009 syslog can generate
1840
03:44:55,740 --> 03:45:03,000
log messages based on the types of services
that are running And includes a severity level
1841
03:45:03,000 --> 03:45:10,160
that ranges from zero the most severe, up
through seven, the least severe syslog can
1842
03:45:10,160 --> 03:45:16,370
generate a lot of log messages. Most network
administrators configure it so that they only
1843
03:45:16,370 --> 03:45:22,439
get alerted when a minimum severity level
has been reached. As a matter of fact, you
1844
03:45:22,439 --> 03:45:29,800
almost never want to capture debug log events
unless you are actively debugging an application
1845
03:45:29,800 --> 03:45:36,790
or service. Just because it generates so much
information. syslog can be configured so that
1846
03:45:36,790 --> 03:45:44,610
network administrators receive their alerts
via text message or SMS message or by email,
1847
03:45:44,610 --> 03:45:51,010
or they may even receive a voicemail message.
Well, syslog is a cool tool. It's not the
1848
03:45:51,010 --> 03:45:58,380
only one that's out there. There's also simple
Network Management Protocol SNMP. SNMP is
1849
03:45:58,380 --> 03:46:05,810
an application layer protocol used to monitor
and manage a networks Health Network or systems
1850
03:46:05,810 --> 03:46:12,270
administrators configure monitors. These are
often called traps. on devices that view the
1851
03:46:12,270 --> 03:46:19,830
operation of a specific item. As in is that
routers interface up or is that routers interface
1852
03:46:19,830 --> 03:46:27,689
down, the monitors periodically communicate
with a network management station or NMS through
1853
03:46:27,689 --> 03:46:35,760
get messages. That's g t messages that the
NMS sends out. The response from the monitors
1854
03:46:35,760 --> 03:46:43,240
is stored in a management information base,
or MIB, which is a type of log file. That
1855
03:46:43,240 --> 03:46:50,680
administrator can custom configure the monitors
with set messages sent from the network management
1856
03:46:50,680 --> 03:46:58,030
station. When an event occurs, as in the interface
goes down, the trap is tripped and the event
1857
03:46:58,030 --> 03:47:05,510
is logged SNMP. Just like syslog can be configured
to just log the event or it can be configured
1858
03:47:05,510 --> 03:47:12,400
to contact the network administrator SNMP
gives network and systems administrators the
1859
03:47:12,400 --> 03:47:20,270
ability to provide more real time monitoring
of a network's performance and health than
1860
03:47:20,270 --> 03:47:27,120
their security information and event management
cm. It's a term for software products and
1861
03:47:27,120 --> 03:47:34,740
services that combined security information
management or sim and security event management
1862
03:47:34,740 --> 03:47:43,229
Sam, si e m may be provided by a software
package network appliance or as a third party
1863
03:47:43,229 --> 03:47:50,530
cloud service. It is used as a means of monitoring
and providing real time analysis of security
1864
03:47:50,530 --> 03:47:57,050
alerts. That is an example of the security
event management function the sim function,
1865
03:47:57,050 --> 03:48:03,140
it can also be used as a tool to analyze long
term data in log files. That's an example
1866
03:48:03,140 --> 03:48:11,250
of the sim function or the security information
management function. Si m can be highly configured
1867
03:48:11,250 --> 03:48:17,950
to the needs of the individual network. Now
that concludes this session on network monitoring
1868
03:48:17,950 --> 03:48:24,240
part one, I talked about the why of network
monitoring. And then I briefly touched on
1869
03:48:24,240 --> 03:48:34,160
some tools for monitoring the network. Hello,
I'm Brian ferrill. And welcome to pace 80s
1870
03:48:34,160 --> 03:48:40,340
session on network monitoring part two. Today
we're going to be talking about active network
1871
03:48:40,340 --> 03:48:46,070
monitoring tools. Then I'm going to move on
to wireless monitoring tools. And we're going
1872
03:48:46,070 --> 03:48:51,880
to conclude with environmental monitoring.
We have a fair amount of ground to cover not
1873
03:48:51,880 --> 03:48:57,320
a whole lot of time. So let's go ahead and
begin the session. Of course I'm going to
1874
03:48:57,320 --> 03:49:04,490
begin by talking about active network monitoring
tools. Port scanners are used to scan a network
1875
03:49:04,490 --> 03:49:10,750
for open ports and protocols. The information
that a port scanner gathers is vital information
1876
03:49:10,750 --> 03:49:17,180
if you want to harden the network. Port scanners
are a great method of finding vulnerabilities
1877
03:49:17,180 --> 03:49:22,820
in the network infrastructure, allowing the
network administrator to plug those vulnerabilities
1878
03:49:22,820 --> 03:49:29,030
before they become a security breach. I do
have to issue a word of caution. You should
1879
03:49:29,030 --> 03:49:36,080
only use a port scanner on a network or system
that you are authorized to scan. Port scanning
1880
03:49:36,080 --> 03:49:42,220
is a possible sign of someone trying to breach
a system in can lead to problems if you're
1881
03:49:42,220 --> 03:49:47,580
not authorized to scan that system. You don't
want to have to try and explain to an information
1882
03:49:47,580 --> 03:49:53,310
security specialist why you were scanning
their network if you're not authorized to
1883
03:49:53,310 --> 03:49:59,790
scan it. A little bit different than a port
scanner are applications that use interface
1884
03:49:59,790 --> 03:50:05,710
monitor Or packet flow monitoring. These are
usually deployed as an active software tool
1885
03:50:05,710 --> 03:50:12,410
to monitor and analyze network traffic within
a network segment. They're commonly called
1886
03:50:12,410 --> 03:50:18,610
packet sniffers or protocol analyzers. They
allow for an in depth look at what traffic
1887
03:50:18,610 --> 03:50:24,050
is on the network, and may reveal security
issues that the network administrator can
1888
03:50:24,050 --> 03:50:31,130
then mitigate. They help to identify top talkers
on a network segment. Top talkers are those
1889
03:50:31,130 --> 03:50:37,610
nodes or applications that generate the most
amount of traffic, packet sniffers can help
1890
03:50:37,610 --> 03:50:44,990
to identify top listeners on a network segment.
A top listener is that interface or the interfaces
1891
03:50:44,990 --> 03:50:50,521
that are receiving the most network traffic.
Or put another way those interfaces that are
1892
03:50:50,521 --> 03:50:57,410
utilizing the most bandwidth for receiving
packets. This can help an administrator when
1893
03:50:57,410 --> 03:51:03,290
they have determined that load balancing might
be needed on the network. Microsoft message
1894
03:51:03,290 --> 03:51:10,570
analyzer and Wireshark are examples of free
packet flow monitoring tools. Now let's move
1895
03:51:10,570 --> 03:51:17,480
on to wireless monitoring tools. And we're
going to begin with the Wi Fi analyzer. A
1896
03:51:17,480 --> 03:51:24,511
Wi Fi analyzer is a similar tool to a protocol
analyzer, but only for wireless networks.
1897
03:51:24,511 --> 03:51:30,580
It sniffs out packets on wireless networks
and gives you statistics on those packets
1898
03:51:30,580 --> 03:51:37,979
that it sees. It can check for bandwidth usage,
channel usage, top talkers, top listeners,
1899
03:51:37,979 --> 03:51:44,860
etc. Just like a packet sniffer can. Wi Fi
analyzers can also identify networks by passively
1900
03:51:44,860 --> 03:51:52,110
scanning the radio frequencies to determine
where traffic is coming from. Given enough
1901
03:51:52,110 --> 03:51:59,070
time, a Wi Fi analyzer can also identify hidden
networks, or those that you don't know about.
1902
03:51:59,070 --> 03:52:06,780
A Wi Fi analyzer can also infer non beaconing
networks. based on data traffic over the radio
1903
03:52:06,780 --> 03:52:13,720
frequencies, they may not be able to discover
the SSID but they can tell the network administrator
1904
03:52:13,720 --> 03:52:20,340
that something is passing traffic there. Another
type of wireless monitoring tool are wireless
1905
03:52:20,340 --> 03:52:26,450
survey tools. They're most commonly used as
a design tool for setting up high quality
1906
03:52:26,450 --> 03:52:32,330
wireless networks. When used in conjunction
with mapping tools, the survey tools can help
1907
03:52:32,330 --> 03:52:38,851
to establish the required amount of access
points to get the proper amount of coverage,
1908
03:52:38,851 --> 03:52:44,800
the ideal antenna placement and the optimum
amount of channel overlap. Wireless survey
1909
03:52:44,800 --> 03:52:54,231
tools can also help to identify possible sources
of radio frequency interference, or RFI. Wireless
1910
03:52:54,231 --> 03:53:00,950
survey tools are often used to eliminate wireless
network performance and security issues before
1911
03:53:00,950 --> 03:53:08,051
they ever have a chance to occur. Let's move
on to environmental monitoring. A network's
1912
03:53:08,051 --> 03:53:13,271
health can be affected by more than just a
network interface failing or a possible security
1913
03:53:13,271 --> 03:53:19,660
breach. Network and systems administrators
also need to be concerned about environmental
1914
03:53:19,660 --> 03:53:25,610
factors. Some of those factors include the
quality and quantity of electrical power being
1915
03:53:25,610 --> 03:53:31,370
supplied to their equipment, in the amount
of heat in the rooms that equipment is kept.
1916
03:53:31,370 --> 03:53:38,130
And also with that the humidity level power
monitoring tools or systems and tools that
1917
03:53:38,130 --> 03:53:43,760
can be used to evaluate the amount of in the
quality of the electrical power being delivered
1918
03:53:43,760 --> 03:53:50,880
to the system, they're often deployed with
or alongside an uninterruptible power supply
1919
03:53:50,880 --> 03:53:58,720
or ups. The monitor will issue an alert when
an issue with electrical power has been identified,
1920
03:53:58,720 --> 03:54:04,590
giving the network or System Administrator
a chance to rectify the problem before any
1921
03:54:04,590 --> 03:54:10,160
equipment has been damaged. All electrical
components are designed to operate within
1922
03:54:10,160 --> 03:54:16,960
a specific heat range. Not only are they designed
to operate within that heat range, but all
1923
03:54:16,960 --> 03:54:22,990
electrical equipment will generate some heat
while they're in operation. And the harder
1924
03:54:22,990 --> 03:54:28,181
that equipment works, the more heat they will
generate. This is where heat monitors come
1925
03:54:28,181 --> 03:54:34,710
into play. The heat monitor allows an administrator
to control the temperature levels before they
1926
03:54:34,710 --> 03:54:41,200
become an issue. humidity is another item
that network administrators need to keep in
1927
03:54:41,200 --> 03:54:47,939
mind. Too little humidity increases the risk
of electrostatic discharge or ESD. But too
1928
03:54:47,939 --> 03:54:54,470
much humidity increases the risk of condensation
on equipment and your electrical components
1929
03:54:54,470 --> 03:54:59,689
do not like that condensation. Humidity monitors
allow administrators
242040
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