The Routing Information Protocol (RIP) is a distance-vector routing protocol that uses hop count as its primary metric. It is one of the oldest routing protocols and was designed in the early 1980s for communication between gateways. RIP prevents routing loops by limiting the number of hops allowed in a path from source to destination, and the maximum hop count allowed for RIP is 15. RIP is known for being easy to configure and use in small networks, but its time to converge and scalability are poor compared to other routing protocols like EIGRP, OSPF, or IS-IS. RIP operates on the application layer of the OSI model and uses the User Datagram Protocol (UDP) as its transport protocol, assigned to the reserved port number 520. RIP messages use UDP datagrams, and all RIP messages exchanged between routers are encapsulated in a UDP datagram. RIP has three versions: RIP Version1, RIP Version2, and RIPng. RIP isnt generally as productive as other directing conventions, but it can be useful as a backup in case of an emergency.