GNS3 Service Provider Core and Edge Lab

To overcome some “boring” Layer 2 stuff of the CCIE RS exam preparation and to do some tests with BGP peering, Cisco Performance Routing (PfR) and DMVPN I decided to setup a Service Provider network in GNS3.

The network uses two hierarchical layers - A core layer and a distribution layer. It is split into four regions: North, East, South and West.

The core part is build with four devices in a ring topology. The distribution layer is made of four provider edge devices connected to the core layer. Additionally there are two devices facing other AS and acting as AS boundary routers. I know that we lack some redundancy but for the moment it should be ok…

All devices within AS 1896

run IS-IS Level 1-2
have MPLS enabled on the interfaces connecting the core devices to each other and between core device and the Provider Edge devices

The device northasbr acts as the BGP route reflector server. All other Provider Edge devices run BGP as route reflector clients.

The core is BGP free.

To get some prefixes into the BGP table there are a couple of loopback interfaces on the devices AS33, AS77 and AS99 which are redistributed. Those three devices run BGP. AS33 and AS77 have a peering with AS1896.

This is how the topology looks like.

See also