If we don't enable a specific routing protocol....

[sawquecisco]

(for example rip), then a network information is come by rip protocol to our router, what happens then?

1-) Does router discard information that is brought with unenabled routing protocols on that router? or what?

2-) So is it adviced that to enable all the routing protocols? What are the trade-offs?

Thanks...

[Jan Hrnko]

Hi,

yes the router will ignore such routing information unless it has this protocol enabled and configured properly (you need first to add networks that you want to be part of the routing process).

But I don't think it is wise to enable ALL routing protocols. You need to enable just the routing protocol you choose and add just the networks you want to be involved in the routing process. The choice of routing protocol depends on what your network looks like and on the features you want to implement. I think that if you use more routing protocols it would consume more cpu and bandwidth. Also if you would use more routing protocols with the same information, only routes with best(lower) administrative distance would be installed (this would make the use of more protocols worthless). For example, same route in RIP, OSPF and EIGRP has administrative distance of 120(RIP), 110(OSPF) and 90(EIGRP) so only the routes learned from EIGRP would be installed in the routing table.

Best regards,

Jan