Routers utilize the IP addresses to make decisions while directing traffic and do not care about the transport protocol.
The IP addresses would map to the network layer in OSI model .
Routers use the UDP protocol to communicate with RIP.
But then how does router sends RIP messages which are encapsulated inside UDP ?
- RIP is a routing protocol to help IP to route it's datagrams through the Autonomous Systems.
- RIP messages are encapsulated inside UDP .
- UDP user datagrams are encapsulated inside IP datagrams.
So that means RIP runs at the application layer but create forwarding tables for IP at the network layer.