Here you can find a few samples of RIPv2 configuration:
1. "Clear Text" RIPv2 authentication
int fa0/0
ip rip authentication key-chain CISCO
!
key chain CISCO
key 1
key-string CISCO
accept-lifetime local 00:07:00 Mar 1 2002 infinite
send-lifetime local 00:07:00 Mar 1 2002 infinite
2. MD5 RIPv2 authentication
int fa0/0
ip rip authentication mode md5
ip rip authentication key-chain CISCO
!
key chain CISCO
key 1
key-string CISCO
accept-lifetime local 00:07:00 Mar 1 2002 infinite
send-lifetime local 00:07:00 Mar 1 2002 infinite
3. Filtering routes that router sends to their neighbors
router rip
distribute-list 10 in FastEthernet0/0
!
access-list 10 deny 150.1.0.0 0.0.255.255
access-list 10 permit any
4. Default route
Router will send Default Route on Serial 1/0 interface, but only if it has 172.68.16.0/24 route in routing table.
router rip
version 2
network 172.68.16.0
default-information originate route-map condition
!
route-map condition permit 10
match ip address 10
set interface s1/0
!
access-list 10 permit 172.68.16.0 0.0.0.255