Nuts and Bolts
Neighbor Establishment
- Both protocols use periodic multicast Hello packets, ÅgI heard youÅh mechanism to establish 2-way communication
- Both protocols have settable hello/holding timers to allow tradeoff between stability, overhead, and responsiveness
- OSPF requires hello and holding timers to match on all routers on the same subnet (side effect of DR election algorithm) making it difficult to change timers without disruption