Service Provider Network Configuration with IS-IS 445

Gateway of last resort is not set

192.168.1.0 255.255.255.255 is subnetted, 1 subnets B 192.168.1.1 [20/0] via 192.168.3.9, 00:05:43

192.168.2.0 255.255.255.255 is subnetted, 1 subnets

C192.168.2.1 is directly connected, Loopback0 192.168.3.0 255.255.255.252 is subnetted, 2 subnets

C192.168.3.8 is directly connected, Serial0

B192.168.3.4 [20/0] via 192.168.3.9, 00:05:43

Tag Switching Forwarding Tables

In this section, the mapping of tags to IP prefixes shows that a complete LSP exists between the loopback addresses on the Atlanta and Raleigh POP routers. With an end-to-end LSP, the Core router only needs to examine the label, and therefore does not require full knowledge of the peer subnets.

Atlanta POP Router Forwarding Table

The Atlanta POP router will label-switch packets to the Raleigh POP router, as you can see in its forwarding table:

Core POP Router Forwarding Table

The Core router will label-switch labeled packets between the POP routers, as you can see in its forwarding table:

446 Appendix B Service Provider Tag Switching with OSPF and IS-IS

Raleigh POP Router Forwarding Table

The Raleigh POP router will send labeled packets to the Atlanta POP router, as you can see in its forwarding table: