Cisco - Configure OSPF with MD5

Q. We are currently using OSPF as routing protocol. Can you please help me how to configure our OSPF to make it more secure and encrypted? We use 14.1.0.0/16

A. To encrypt your OSPF or even your RIP version 2 network, you may use an MD5. First, you need to generate a that you can use for authentication purposes.

Note: If the match, the router accepts the packets, otherwise, rejects it.

Here's what you can do to one of your routers. Just do the same to other routers. Remember that the should be the same to all routers to match!

Router(config)#router ospf 1

Router(config-router)#network 14.1.0.0 0.0.255.255 area 0

Router(config-router)#area 0 authentication message-digest

Router(config-router)#exit

Router(config)#int fa0/0

Router(config-if)#ip ospf message-digest-key 1 md5

Save it.

Note: The router's fa0/0 is the one connected to OSPF area (network).