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Associate a network with a routing protocol.


       a                      b           c                            d          e                            f

PC1 <-------------------> Router1 <--------------------------> Router2 <-------------------------> PC2

I associated c interface(in Router1) with RIP; then I expected to see Router2 have a entry for PC1-Router1 network. Because I thought When someone configure an interface with a routing protocol,  router sends its information to other routers via that interface. That meant router2 must know the other network. But it doesn't.

I think it is because; like sender; also reciever must configure with same routing protocol. Right?

If it is right. Is it allowed to configure one interface with more than one routing protocol? If it is allowed, so the best thing is configure all the interfaces with all the routing protocols so router has more options to choose best way to add its routing table. Is that right? Are there any disadvantages?



Associate a network with a routing protocol.

You are correct in your first question - each router must be running the same routing protocol (RIP, in this case) in order to send/receive the updates.

You can configure more than one protocol per router, but there are disadvantages:

1) complexity - it becomes more of a burden to manage to some extent

2) resources - each routing protocol consumes resources (CPU, memory) of the appliance

3) overhead - each protocol is now consuming some amount of bandwidth on your links

In the end, the protocol with the lowest administrative distance is going to win, anyway.

Another thing to remember:  RIPv2 auto-summarizes to classful boundaries by default.  Depending on your addressing scheme, you may want to add the "no auto-summary" command to your RIP configuration.

Good luck!