Enable Interface-Specific Authentication

1. Enter the configuration mode for the interface.

   SEFOS# configure terminal
   SEFOS(config)# interface vlan 1
   SEFOS(config-if)# exit
   

2. Enter the configuration mode for the router.

   SEFOS# configure terminal
   SEFOS(config)# router rip
   SEFOS(config-router)# network 10.0.0.1
   SEFOS(config-router)# exit
   

3. On switch 1, enable interface-specific authentication on the specific interface.

   SEFOS(config)# interface vlan 1
   SEFOS(config-if)# ip rip authentication mode md5 key-chain 12345