IP Routing

RIP-1/RIP-2 Compatibility

In Chapter 2, we configured RIP as follows on NewYork in TraderMary’s network:

hostname NewYork
...
router rip
network 172.16.0.0

This configuration of RIP on a router running IOS 11.1 or later allows the receipt of both RIP-1 and RIP-2 updates but the sending of only RIP-1 updates.

To modify this configuration to allow the receipt of only RIP-1 updates, specify Version 1 under RIP. In the new configuration, the router will discard any RIP-2 updates it receives and will send only RIP-1 updates:

hostname NewYork
...
router rip
version 1
network 172.16.0.0

By extension, the following modification allows the receipt of only RIP-2 updates. In this configuration, the router will discard any RIP-1 updates it receivesand will send only RIP-2 updates:

hostname NewYork
...
router rip
version 2
network 172.16.0.0

RIP-1/RIP-2 Interworking

The behavior of RIP can be modified further in interface configuration mode to allow for interworking between RIP-1 and RIP-2 routers.

To send only Version 1 updates out of an interface (for example, when only RIP-1 listeners exist on a network), enter the following command in interface configuration mode:

ip rip send version 1

To send only Version 2 updates out of an interface (e.g., when only RIP-2 listeners exist on a network), enter the following command in interface configuration mode:

ip rip send version 2

To send Version 1 and 2 updates out of an interface (e.g., when RIP-1 listeners and RIP-2 listeners coexist on a network), enter ...