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New Member

RIPv1 and CIDR

Hello all

Could somebody help me with this subject?

I have two routers, one with RIPv1 and the other with RIPv2. In the RIPv2 router I have a static route redistributed within RIPv2.

When the RIPv1 router receive this route, it learn it correctly. In the route table of RIPv1 router appears the route How is it possible, when RIPv1 don't see the mask of the routing updates?

Thank you in advance.


Hall of Fame Super Silver

RIPv1 and CIDR


Would you post the interface configuration of the router running RIPv1? In particular we would like to see if the interface of the router is configured with an address in 172.16 and with a /12 mask.



New Member

Re: RIPv1 and CIDR


If you will allow me Jaime, I put a link where you can see the topology and the show ip route....

El mensaje fue editado por: Raul Martinez Lara

RIPv1 and CIDR

it's corect - RIPv1 is not CIDR -aware, it doesn't send a subnet  mask in the updates, but is a correct "class-full" network with correct mask, and RIPv1 simply use this information and put thia subnet "correctly" into routing table. 

If you would redistribute something like, I'm pretty sure you will see in RIPv1 the same network.

New Member

RIPv1 and CIDR

        ¿Are you sure that network is a "class-full" network with correct mask?The class-full masks are /8,/16 and/24....¿Do you agree?


Re: RIPv1 and CIDR

sorry, your're right I've mixed the subnet mask for the Private range with a B-class mask, sorry, sorry. forget it

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