RIP Question, not rest in peace :)

[Iluvnetwork]

Network A --- Router 1 --- Router 2 --- Router 3, Router4 (Router 3 and Router 4 are both connected to Router 2)

My understanding: If network A is down, router 1 deletes the route to network A on the routing table and send poisoning packets to Router 2 using 255.255.255.255. Route 1 will deletes the route to network A on the inter database after 240 seconds. Router 2 receives the poisoning packet from router 1, deletes the route to network A on the routing table, sends poisoning pakcet to Router 3 and Router 4, and sends poison reverse packet to Router 1.

Instructor: If network A is down, router 1 deletes the route to network A on the routing table and send poisoning packets to Router 2 using 255.255.255.255. Route 1 will deletes the route to network A on the inter database after 60 seconds since invalid time is skipped (240 - 180). Router 2 receives the poisoning packet from router 1, doesn't delete the route to network A on the routing table until it receives poisoning reverse packets from Router 3 and Router 4, sends poisoning pakcet to Router 3 and Router 4, and sends poison reverse packet to Router 1.

I tested on both Packet Tracer 7.1 and GNS3 and got different answers. If you know the correct answer, please let me know :)

[Julio E. Moisa · Accepted solution]

Hi

As I remember the network is removed and the poisoned route is sent to the neighbor they remove the route quickly and they dont have to wait for the maximum time to remove it. It is done around of 1 minutes on the neighbors. In EIGRP is done faster.

Please check this link:

https://supportforums.cisco.com/t5/lan-switching-and-routing/rip-v2-triggered-route-poisoning-and-holddown-time/td-p/1634266

Hope it is useful

:-)

[Iluvnetwork]

Thank you very much. Whenever I read Peter's explanations, I always get enlightened :)

[Julio E. Moisa]

It was a pleasure, have a great day

:-)