All language subtitles for Free-CCNA-IPv6-Part-3-Day-33-CCNA-200-301-Complete-Course_en

This is a free, complete course for the CCNA.

If you like these videos, please subscribe\n

Also, please like and leave a comment, and\n

In this video we will wrap up our studies\nof IPv6.

Honestly, there is so much more I want to\n

up our IPv6 studies for the CCNA.

However, in future videos I will continue\n

Some labs will use IPv4, some will use IPv6,\nsome will use both.

Same for the examples in my lectures.

A lot of people studying for the CCNA don’t\n

just because they don’t spend a lot of time\n

Outside of a few IPv6-specific lessons everything\n

To review, here are the IPv6-specific topics\n

The focus of today’s video will be topic\n

you already know from IPv4 to IPv6.

Here’s what we’ll cover in this video.

First up, a correction about my previous IPv6\nvideos.

It’s not a big mistake, in fact it’s a\n

Then we’ll very briefly cover the IPv6 header.

We’ll also cover neighbor discovery protocol,\n

That’s right, IPv6 doesn’t use ARP.

Next we’ll cover something called SLAAC.

Finally, the main topic of today’s video\nis IPv6 static routing.

Although it’s probably the most important\n

because you already understand IPv4 static\n

As always, make sure to watch until the end\n

ExSim for CCNA, the best practice exams for\n

To check out ExSim, follow the link in the\nvideo description.

So, that correction I wanted to make is about\n

When making these videos I do a lot of research\n

as possible, and I often learn many new things\n

While preparing these IPv6 videos, I was looking\n

Let me briefly explain what an RFC is.

An RFC, which stands for Request for Comments,\n

and associated organizations like the IETF,\n

RFCs are the official documents of Internet\n

So, if you really want to go in-depth about\n

it, there are tons of RFCs that document OSPF,\n

RFC 5952 is titled ‘A Recommendation for\n

Before this RFC, IPv6 address representation\nwas more flexible.

For example, you could remove leading 0s from\n

You could replace all-0 quartets with a double\n

You could use upper-case hexadecimal A, B,\n

However, RFC 5952 suggests standardizing IPv6\n

Here are some of the details from that RFC.

So, this IPv6 address MUST be represented\n

The double colon MUST be used to shorten the\n

But if there is just a single all-0 quartet,\n

So, this IPv6 address has two choices for\nthe double colon.

On the left there are three all-0 quartets,\n

So, we MUST shorten it like this, using the\n

Then, if there are two equal-length choices\n

to shorten the one on the left.

So, this address has two choices for the double\n

So, we must shorten the one on the left.

Finally, this is the main one I wanted to\n

e, and f MUST be written using lower-case,\nnot upper-case.

In my videos I have been using both, sometimes\n

now on I will use only lower-case.

However, I’m not the only one who wasn’t\nfollowing this rule.

Here’s a screenshot from a Cisco router,\n

So, this is technically incorrect.

However, because even Cisco’s devices don’t\n

you write them in upper-case characters.

I guess this RFC isn’t very well-known,\n

But let’s try to follow the standard from\nnow on.

Okay, let’s move on to take a brief look\nat the IPv6 header.

Here it is, thanks to Wikipedia for the chart.

To compare, here’s the IPv4 header we studied\n

Now take another look at the IPv6 header.

One thing that makes it simpler is this word\n

The IPv4 header has a variable header length,\n

But the IPv6 header has a fixed size of 40\nbytes.

That’s why there is a ‘payload length’\n

Layer 4 segment, but no ‘header length’\n

The processing of the IPv6 header is much\n

Okay, I won’t spend a whole lecture on this\n

a brief description of each field.

First up, the version field, just like in\nIPv4.

It indicates the version of IP that is used.

Because this is IPv6, this field will always\n

And that’s all there is to say about this\nfield.

Next up is the Traffic Class field.

It’s used for QoS, quality of service, to\n

For example, IP phone traffic, live video\n

which gives them priority over other traffic.

QoS is something we’ll cover later in the\n

Next up is the ‘flow label’ field.

It’s used to identify specific traffic flows,\n

source and destination, like the interaction\n

I briefly talked about flows in the TCP/UDP\nvideo.

Okay, that’s all for this field.

Next up is the ‘payload length’ field.

It indicates the length of the payload, the\n

So, a value of 1024 in this field would mean\n

The length of the IPv6 header itself isn’t\n

Next is the ‘next header’ field.

It indicates the type of the ‘next header’,\n

It has the same function as the ‘protocol’\n

The next field is the ‘hop limit’ field.

The value in this field is decremented by\n

If the value reaches 0, the packet is discarded.

So, the function is the same as the IPv4 header’s\nTTL field.

Finally, the last two fields are the source\n

As you already know, they are 128 bits in\nlength each.

128 bits for the source, 128 bits for the\ndestination.

These fields contain the IPv6 addresses of\n

Okay, so that was a very brief explanation\n

I will include flashcards to help you remember\nthe fields.

However, I doubt that you will get any direct\n

But I still think it’s good foundational\n

Okay, the next topic is something I didn’t\n

However, it’s an important part of Neighbor\n

First let me just show you how the address\n

An IPv6 solicited-node multicast address is\n

The address begins with a fixed prefix, ff02::1:ff\n

6 hex digits of the unicast address this solicited-node\n

For example, here’s a unicast IPv6 address.

To generate a solicited-node multicast address\n

That’s it, that’s how you generate a solicited-node\n

Try to write out the solicited-node multicast\naddress yourself.

Add ff02::1:ff to them, and you get the answer.

I showed you this output in the previous video\n

I pointed out that routers join the FF02::1\n

But notice this other multicast group that\nR1 joined.

That’s a solicited-node multicast address.

FF02::1:FF, and then 6 more hex digits.

Those last six digits are the same as in this\n

Okay, so now you know how solicited-node multicast\n

introduce NDP and show you how these addresses\nare used.

Neighbor Discovery Protocol, NDP, is a protocol\nused with IPv6.

It’s not directly listed on the exam topics\n

of IPv4 routing, NDP is an essential part\n

It has various functions, and one of those\n

The ARP-like function of NDP uses ICMPv6 and\n

As you probably remember, ARP in IPv4 uses\n

Solicited-node multicast messages are much\n

host, unlike a broadcast which is for all\nhosts.

In the process, two message types are used.

The first one is the neighbor solicitation\n

Note that the NDP neighbor solicitation message\n

I haven’t talked much about ICMP in this\n

messages, perhaps the most famous one being\nping.

After I finish the course I’ll probably\n

Anyway, IPv6 has its own version of ICMP,\n

The other message is the neighbor advertisement\n

Try to remember those ICMP message types,\n

So, here’s the basic function of the neighbor\n

Let’s say I typed PING 2001:db8::78:9abc\n

R1 needs to encapsulate that packet in an\n

To ask for R2’s MAC address, R1 will send\n

So, R1 is basically just saying ‘Hi, what’s\nyour MAC address?’.

Now, to show you how this is different than\n

different addresses in the packet and frame.

Below is this message taken from a Wireshark\n

The source IP is R1’s IP address.

The destination IP address, however, is R2’s\n

How does R1 know R2’s solicited node address?

Well, it knows the unicast address because\n

to automatically calculate the solicited-node\n

The source MAC is the MAC address of R1’s\nG0/0 interface.

That’s the same as in ARP as well.

The destination MAC address is a multicast\n

Notice that in Wireshark it is displayed as\n

can see the real multicast MAC address in\nbrackets.

I haven’t really taught you about multicast\n

them for the CCNA, so don’t worry about\nthe details here.

Just note that the big difference between\n

ARP request message, is that the ARP request\n

is multicast, which is more efficient.

Now let’s see the neighbor advertisement\n

R2 received a message from R1 asking for its\nMAC address.

Basically, in response R2 just teaches R1\nits MAC address.

So, let’s see the different addresses in\nthe message.

R2 will send the neighbor advertisement message\n

the destination will be R1’s G0/0 IP address.

It knows R1’s IP address because it was\n

The source MAC will be R2’s G0/0 MAC address,\n

Again, R2 knows R1’s MAC address because\n

Now, since IPv6 doesn’t use ARP, there isn’t\nan ARP table.

Instead, the devices will keep an IPv6 neighbor\ntable.

Keep in mind I’m showing this on Cisco routers,\n

Here’s R1’s IPv6 neighbor table, you can\n

First, the IPv6 address column.

Notice that R1 has an entry for both R2’s\n

It learned that link-local address automatically,\n

Next, the age column indicates how long ago\n

The link-layer address column shows R2’s\n

course, shows the interface this entry was\nlearned on.

There is also a ‘state’ column, but for\n

Basically, this REACH state means that the\n

By the way, this is R2’s neighbor table,\n

Okay, I will briefly explain one more function\n

Another function of NDP allows hosts to automatically\n

Again, two messages are used for this process.

First one, router solicitation, which is ICMPv6\ntype 133.

Don’t mix this up with the neighbor solicitation\n

These are sent to multicast address FF02::2,\n

This message asks routers on the local link,\n

This message is sent when an interface is\n

The next kind of message is the router advertisement,\n

These messages are sent to multicast address\n

So, these messages are received by all hosts\n

Using this message, the router announces its\n

about the link, the local network.

These messages are sent in response to RS\nmessages.

If a router receives an RS, it will send an\nRA.

However, even if the router doesn’t receive\n

To give a brief demonstration, I’ll use\nR1 and R2 again.

Once again, these functions aren’t unique\nto routers.

Although only routers send router advertisements,\n

So, let’s say we enable R2’s G0/0 interface.

It automatically sends an RS message, asking\n

R1 replies, identifying itself.

There are lots of ways this can be used, for\n

default gateway from these RA messages.

But let’s move on to the next topic, and\n

SLAAC stands for Stateless Address Auto-configuration.

Yes, another way to configure IPv6 addresses.

When using SLAAC, hosts use the RS and RA\n

link, for example 2001:db8::/64.

Then they use that prefix to automatically\n

When using the IPv6 address eui-64 command,\n

However, the command for SLAAC, IPV6 ADDRESS\n

It’s because NDP is used to learn the prefix\n

Then the device will use EUI-64 to generate\n

depending on the device and maker.

Let me show you that on a Cisco router.

R1 is configured with an IPv6 address, but\n

So, I use the command IPV6 ADDRESS AUTOCONFIG\n

the global unicast address it generated, and\n

Once again, keep in mind that although I’m\n

SLAAC is a standard function of IPv6, and\n

they don’t use Cisco IOS commands, of course.

Okay, one final point about NDP before moving\n

This is a simple concept, and you should be\n

Duplicate Address Detection, DAD, which is\n

if other devices on the local link are using\n

Any time an IPv6-enabled interface initializes,\n

an IPv6 address is configured on an interface,\n

address, the device performs DAD to check\n

DAD uses two messages that you already learned\n

So that’s good news, you don’t have to\n

To perform DAD, the host will send an NS to\n

If it doesn’t get a reply it knows the address\nis unique.

However, if it does get a reply, a neighbor\n

host on the network is already using the address.

On a Cisco router, you’ll get a message\n

Exactly what happens next depends on how the\n

etc, but we don’t have to go any deeper\ninto DAD for the CCNA.

Finally, let’s get into IPv6 static routing.

As a reminder, here’s what you need to know\nfor the CCNA.

You should be able to configure and verify\n

But now that you’re a little more experienced,\n

routes in general, not just for IPv6.

IPv6 routing works the same as IPv4 routing.

A packet arrives on one of the router’s\n

address in its routing table, and then forwards\n

Although IPv6 routing works the same, the\n

and the two routing tables are separate as\nwell.

You’ve already seen how the router builds\n

IPv4 routing is enabled on Cisco routers by\ndefault.

However, IPv6 routing is disabled by default,\n

If IPv6 routing is disabled, the router will\n

but will not ‘route’ IPv6 traffic, meaning\n

Always make sure to use the IPV6 UNICAST-ROUTING\ncommand.

If everything about your IPv6 configuration\n

isn’t working, there’s a big chance that\n

To demonstrate IPv6 routing, we’ll use this\nnetwork here.

But before we actually configure static routes\n

So, here’s R1’s IPv6 routing table.

Just like in IPv4, a connected ‘network\n

A network route is a route to a network, a\n

Also, a local ‘host route’ is automatically\n

A host route is a route to a single specific\n

For example, here you can see the connected\n

A /64 connected network route, and a /128\nlocal host route.

Some of you might have noticed this route\n

It says ‘via Null0’, which is an interface\n

so this discards multicast traffic.

This route was automatically configured, but\n

If you’re curious, try searching on google\nfor more information.

Also one more thing I’d like to point out,\n

R1’s G0/0 and G0/1 both have link local\n

Now let’s actually take a look at static\nroutes.

Here’s the IPv6 static route command, written\n

If you haven’t seen a command written like\n

Although it’s not required knowledge for\n

to read commands like this for your future\nstudies.

This first part is easy enough to understand.

The command begins IPV6 ROUTE, and then you\n

Now let explain this next part in the curly\nbrackets.

Curly brackets mean a required choice.

So, you HAVE to either enter a next-hop address,\n

That’s what the square brackets mean, the\n

Finally, you can see AD in square brackets,\n

It’s administrative distance, which you’ll\n

Now, there is actually a name for each of\n

on if you specify just the exit interface,\n

This concept isn’t unique to IPv6, by the\n

First up, a ‘directly attached’ static\n

For example, on R1 you might use this command:\n

Okay, the next type is a recursive static\n

On R1, you might use the command IPV6 ROUTE\n

destination, and then 2001:db8:0:12::2, telling\n

It’s because it requires a ‘recursive’\n

its routing table multiple times.

First, it has to look up the destination.

Then it has to look up the next hop to know\n

Let me demonstrate, here’s R1’s routing\n

If it receives a packet destined for PC2’s\n

It says the next hop is 2001:db8:0:12::2.

So R1 has to look up that address now.

It finds this matching entry, so it knows\n

Okay, the next type of static route is the\n

exit interface and next hop are specified.

For example, to reach that same network from\n

Okay, try to remember these three kinds of\n

the same for both IPv4 and IPv6.

I didn’t specifically mention these types\n

can have directly attached, recursive, and\n

Before moving on, I have to point one thing\n

In IPv6, you can’t use directly attached\n

So, this command I wrote here actually won’t\nwork.

G0/0, which stands for gigabitETHERNET0/0,\n

Actually, the router will let you enter the\n

configuration, but the route just won’t\nwork.

R1 simply won’t send the packet.

If it was a serial interface, for example,\n

Although directly attached static routes work\n

You have to use a recursive or fully specified\n

Okay, let’s look at an example IPv6 route\n

First up, a network route, a route to a specific\nsubnet.

I configured this route on R1.

IPv6 ROUTE 2001:db8:0:3::/64, which is the\n

Then I specified the next hop, 2001:db8:0:12::2,\n

This tells R1: if you receive a packet with\n

Next up, a host route, a route to single specific\nhost.

For example, let’s configure host routes\n

Here’s the route to PC1, and here’s the\nroute to PC2.

Since there are probably plenty of other PCs\n

use host routes in a situation like this,\n

But I just wanted to demonstrate how to configure\n

Okay, the next type is a default route.

Let’s configure a default route on R3.

Here it is, notice the ::/0 which is like\n0.0.0.0/0 in IPv4.

Okay, so here are four IPv6 static routes.

Think about the different static route types\n

attached, recursive, and fully specified.

Of those previous types, what type are these\n

They are all recursive, they all specify only\nthe next hop.

Okay, now I left out one type of static route\n

Although this example network here doesn’t\n

configure a floating static route?

By raising the AD, we can make static backup\n

If the main route to the destination was learned\n

the static route’s AD to higher than 110,\n

If the main route to the destination was learned\n

to set the static route’s AD to higher than\n

Always set the AD to higher than the main\nroute.

Finally, I want to bring up a point that I\n

about using a link-local address as the next\n

Here on R1, I tried to configure a route to\n

However, I got an error message and the command\ndidn’t work.

‘Interface has to be specified for a link-local\nnexthop’.

So, if you want to use a link-local address\n

next hop address and the exit interface.

What’s this kind of static route called,\n

It’s a fully specified static route.

Here’s that route in the routing table.

The reason you need to specify the exit interface\n

the router isn’t able to figure out, on\n

Okay, let’s review before going on to the\nquiz.

First in this video, I showed you some basic\n

Nothing important for the test, but still\n

Then I briefly introduced each field of the\nIPv6 header.

It has a fixed size of 40 bytes and is much\n

I doubt there will be any specific questions\n

consider it fundamental networking knowledge.

Then I introduced neighbor discovery protocol,\nNDP.

NDP is a very important part of IPv6 which\n

One of those functions is to replace ARP by\n

Another is for automatic discovery of routers\n

Router Advertisement messages.

Those Router Solicitation and Router Advertisement\n

SLAAC, Stateless Address Auto-configuration,\n

Finally, we covered IPv6 static routes.

Remember those three types, directly attached,\n

Also network, host, default and floating routes.

All of those types apply to both IPv4 and\n

review, but some of it was new.

Remember to watch until the end of the quiz\n

best practice exams for the CCNA.

Okay, let’s get started with quiz question\n1.

R2 sends a message to R1, to tell R1 about\n

What kind of message does R2 send to R1?

Pause the video to think about the answer.

The answer is B, NA, neighbor advertisement.

R1 would have sent an NS, neighbor solicitation\n

In response, R2 sends an NA to R1, telling\n

This is like the ARP function of IPv4.

RS, router solicitation, and RA, router advertisement,\n

Okay, let’s go to question 2.

You configure an IPv6 address on R1’s G0/0\ninterface.

What kind of message will it send to perform\nDAD?

Pause the video to think about the answer.

The answer is D, NS, neighbor solicitation.

When an IPv6 address is configured on an interface,\n

interface’s own solicited-node multicast\n

If no reply comes, it knows that the address\nis unique.

If it receives a reply, it means that another\n

Okay, let’s go to question 3.

R1 sends an RA message to devices on the local\n

the prefix of the network, etc.

What IPv6 address does R1 send the message\nto?

Pause the video to think about your answer.

IPv6 routers send RA, router advertisement,\n

link about the router’s presence, as well\n

To do this, the all-nodes link-local multicast\n

Okay, let’s go to question 4.

You configure the following IPv6 static route,\n

So, two of the following static route types\napply to this route.

Pause the video to think about your answer,\nselect two.

Okay, the answers are A, fully specified,\nand B, network.

It’s a fully specified static route because\n

It’s a network route because its destination\n

Which of the following commands configures\n

Pause the video to think about your answer.

Okay, the answer is C. A recursive static\n

A is a directly attached static route and\n

A host route is a route to a single host,\n

A and D are network routes, and B and C are\nhost routes.

So C is the only one that is both a recursive\n

Okay, that’s all for the quiz.

Now let’s take a look at a bonus question\n

Okay, here's today's Boson ExSim practice\nquestion.

You issue the ipv6 route 2001:db8:2::/64 2001:db8:1::2\n

When you attempt to ping the GigabitEthernet0/1\n

2001:db8:2::2 command on RouterA, the ping\nfails.

Which of the following is most likely the\nproblem?

Okay, so here are the four options.

Please pause the video and find the correct\nanswer.

Okay, let's check the answer.

A, RouterB does not have a route to the 2001:db8:1::/64\nnetwork.

That is probably not the problem, that is\n

RouterA does not have a default gateway.

So, RouterA does not have a default route.

Well, we just configured a route to this network,\n

So B is probably not the answer.

RouterC does not have a route to the 2001:db8:1::/64\nnetwork.

For RouterA to successfully ping RouterC,\n

RouterC must be able to reach RouterA.

So RouterC does need a route to this network.

So C might be the correct answer.

RouterB does not have a route to the 2001:db8:2::/64\nnetwork.

Again, that is a connected network on RouterB,\n

So, that leaves us with C. I believe C is\nthe correct answer.

I'll click on Show Answer down here to check.

Okay, here's Boson's explanation.

You can pause the video now to check it out.

And also notice some references to Cisco documentation.

I highly recommend using the Cisco documentation\n

Okay, so that's Boson ExSim for the CCNA.

I highly recommend these practice exams.

I used them myself, they're great, and if\n

There are supplementary materials for this\nvideo.

There is a flashcard deck to use with the\nsoftware ‘Anki’.

Note that I have added the tag ‘ipv6’\n

two videos, so you can use Anki to specifically\n

There was a lot to memorize in these videos,\n

There will also be a packet tracer practice\n

That will be in the next video.

Sign up for my mailing list via the link in\n

the flashcards and packet tracer lab files\nfor the course.

Before finishing today’s video I want to\n

To join, please click the ‘Join’ button\nunder the video.

Thank you to TheGunguy, l33america, Brandon,\n

Prakaash, Nasir, Erlison, Apogee, Wasseem,\n

Ed, Value, John, Funnyydart, Scott, Hassan,\n

Sidi, Boson Software, Charlesetta, Devin,\n

Sorry if I pronounced your name incorrectly,\n

One of you is still displaying as Channel\n

me know and I’ll see if YouTube can fix\nit.

This is the list of JCNP-level members at\n

If you signed up recently and your name isn’t\n

Please subscribe to the channel, like the\n

with anyone else studying for the CCNA.

If you want to leave a tip, check the links\nin the description.

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