In PIM Dense Mode, why does an Assert loser send a Prune message to the winner? What is the actual motivation for this?
I found a post that answers my question. For anyone that might be interested:
Edit: So the answer to my question is: simply to inform the winner to stop sending traffic because it doesn't need it. Now, there are more scenarios that may appear:
- Scenario 1: there are only the two routers on the segment: In this case the winner receives the PIM Prune message and it stops sending the traffic.
- Scenario 2: there is a third router (downstream) on the segment: In which case, both the winner and the third router receive the PIM Prune message, and the third router responds to it by sending a PIM Join to override the PIM Prune sent by the loser.
- Scenario 3: there is an IGMP receiver on the segment: in which case the winner won't stop forwarding traffic, I assume that because of the IGMP active client.