[AUDIO LOGO]
Hello, and welcome to Discovering MPLS Layer 3 VPNs.
In this skill, we're going to be going over
the technical information about layer 3 VPNs as far as
how they work, how they function,
and all of the different moving parts.
There are quite a few moving parts
here that we need to deal with.
Each of those moving parts is designed
to address a specific issue.
So what are the moving parts that we need to discuss?
Well, we're going to start off by talking about VRFs,
or Virtual Routers and Forwarders,
and how we use those to separate customer routes on the network
edge.
But once those have been separated,
we then have to start talking about core routing.
What do we mean by core routing?
Well, the routes have to get from one PE router
to another PE router.
And that means they have to be kept separate
as they pass through the service provider core.
The next problem we're going to have to address
is route distribution.
Now, what this really means is once we pass the routes
through the core, then we have to determine
which VRF those routes go in on the egress router.
We have to know how to separate the routes per customer.
Now, something else we're going to be addressing here
is central service VPNs.
These are, of course, optional.
But the service provider can use these to offer services
to their customers.
But we have to be careful that we
don't join the customers to gather or leak
the routes between the customers through the central service
VPN.
Finally, we're going to wrap up by talking about CE-PE routing.
This is the routing protocol that's
going to be run between the customer and the provider.
We have some different choices here.
And it really is up to the service provider
to choose which protocols they're going to support.
So we'll talk about some of the pros and cons of each one.
I will throw out there that using BGP
is really the most common choice.
However, there are other options available.
So let's go ahead and jump in and get started.
Lots of things to talk about.
We're going to have a lot of fun.
I'll see you in the next video.