Original subtitles

All right so we're going to move down a layer here and talk about Layer 2.

So remember ip for ip 6 IP addresses as a whole.

That is Layer 3.

We're talking about routing here in layer two.

We're going to be talking about a MAC address or a physical address.

Now Mac stands for media access control and that is identified here in our IRF config as this ether

here.

So we could think of this as our physical address and a way that we communicate when we are using switches

which is communicate over this physical address.

This is kind of how they know what device is.

What.

So what we say here is if we have a device say you just built a computer and you're installing your

network interface card or your Nick you're going to plug it in and you're going to have a mac address

for that Nick your cell phone.

That's going to have a mac address anything that's using a network interface is going to have a mac

address.

So these MAC addresses are important because they utilize layer two or switching and they are how we

communicate over switches.

Now there's something to be noted briefly about MAC addresses.

Now MAC addresses have identifiers.

So as you can see here this MAC address has six different pairs of two.

Right.

And what we can do is we could take the first three pairs and we can just copy this and we can go out

and we can try to put it into a MAC address.

Look up now for this one.

This is just going to be VM where I'm not sure if it's actually going to come up but I'm going to go

ahead and paste it and see what happens and you can see that the vendor actually shows up as VM where

so the first three pairs here are identifiers and we can identify what we're up against.

If you've ever looked in your house and you've looked at your network and you you're trying to find

a device and you see the IP address but the IP address isn't really help you identify it you might see

something along the lines of a MAC address because your your home device say your your router might

also be what's called a layer to slash Layer 3 device meaning it's doing switching and routing for you

and it will also know the MAC address of that device.

So you can take the first three pairs here.

Put those into the Google machine and see if you can identify what that device is.

So if I was unsure this didn't have a hostname or Device name and I could just reach out and say OK

well let me me look these up.

Maybe it'll give me an inkling.

It's not going to tell me the exact device but if I know it's running VM where then I can say oh you

know that's my host machine running or if it's related to like Texas Instruments or something maybe

I know that device in my house.

So this is just a quick way to look up devices and know about them.

The other option or other thing that you need to know here is just that again Mac addresses layer two

related to switching.

I'm just trying to repeat this and get this into your head so that's all we need to know from this lesson

and we're gonna go ahead and I'll catch you over in the next lesson.