- Not only can we have virtual servers and virtual switches
like we talked about in our last lesson,
we can also have virtualized data paths.
For example, let's say that we've got a couple of routers
that want to be OSPF neighbors.
They challenge is they live in different cities
and we've got to cross maybe the internet
to get between those two routers.
They're physically not next to each other.
What do we do?
Well, we could have a tunnel between them
to make them logically look like they're adjacent
and form that OSPF neighborship.
Another way of creating a virtualized data path
is to have a physical router
with multiple virtual routers running inside of it.
A service provider, for example,
might have different customers
and they each need their own router
with their own routing at table.
We don't want those routing tables to leak
from customer A to customer B probably.
Well, we can keep all those isolated inside
of the same physical router.
In fact, that's what we're going to look at next.
It's a feature called VRF.