Authentication/Authorization/Accounting

Authentication is the process of identifying who the entity is or what it claims to be. Example To log in into the computer we need user-name and password, this is authentication.
Authorization is which resources a user or an entity can access.
Accounting keeps track of all what resource have been accessed and for what interval.


Rip version2 supports authentication. It authenticates the route updates. Rip authenication can be plain or encrypted using MD5

configuration for plain text authentication

r>enable
r#conf t
r(conf)#key chain ring
r(conf-keychain)#key 1
r(conf-keychain-key)#key-string cisco
r(conf-keychain-key)#exit
r(conf)#int s0/0
r(conf-if)#ip rip authentication key-chain ring



configuration for MD5 authentication

After configuring the key chain and key string use MD5 authentication under an interface

r(conf-if)#ip rip authentication mode MD5


Eigrp supports only Md5 authentication

Configuration

r>enable
r#conf t
r(conf)#key chain ring
r(conf-keychain)#key 1
r(conf-keychain-key)#key-string cisco
r(conf-keychain-key)#exit
r(conf)#int s0/0
r(conf-if)#ip authentication eigrp 10 key-chain ring
r(conf-if)#ip authentication eigrp 10 mode Md5