RIPv1 vs. RIPv2 (continued)
RIPv1 RIPv2
Classful Classless
Broadcast based Uses Multicast 224.0.0.9
No support for VLSM Supports VLSM networks
No authentication Allows for MD5 authentication
No support for discontiguous
networks
Supports discontiguous networks
TABLE 3 . 1 3 RIPv2 Authentication Commands
Command Meaning
version Configures the version of RIP which is running
key chain name This just creates a key chain name
key key
Key-string string This is the authentication string that is sent and received in the
packets by the routing protocol being authenticated
ip rip authentication
key-chain chain_name
Enables authentication on the interface and configures the key
chain that will be used
ip rip authentication
mode md5
Optional, but highly recommended. If you do not add the md5
authentication, then the key-chain is sent in clear text.
Configuring RIPv2 is pretty straightforward. Here’s an example:
Lab_C(config)#router rip
Lab_C(config-router)#network 192.168.40.0
Lab_C(config-router)#network 192.168.50.0
Lab_C(config-router)#version 2
That’s it—just add the command version 2 at the (config-router)# prompt, and
you are now running RIPv2. Now, let’s add authentication to the RIP route
updates. Lab_C#config t
Lab_C(config)#key chain todd
Lab_C(config)#key 1
Lab_C(config)#key-string 12345
Lab_C(config)#interface serial 0/0
Lab_C(config-if)#ip rip authentication key-chain todd
Lab_C(config-if)#ip rip authentication mode md5
OK, let’s verify RIP routing