Routing Information Protocol (RIP)

Routing Information Protocol (RIP)
The Routing Information Protocol (RIP) is currently the most common type of routing protocol.
RIP bases its routing path on the distance (number of hops) to the destination. In 1982,
RIP appeared in the Berkeley Software Distribution (BSD) version of UNIX as part of TCP/IP
protocol suite. Today, many other routing protocols, such as AppleTalk’s routing protocol, use
RIP as a foundation. Other companies, such as Novell and Banyan, have RIP-like routing protocols
as well. Also, Microsoft expanded NT’s WAN capabilities by adding support for routing
packets based on RIP. A router implements RIP by storing information in its routing table. A destination column indicates
all possible destination networks, a next-hop field identifies the router port to send the
packet next, and the distance field refers to the number of hops it will take to reach the destination
network. A RIP routing table contains only the best route to a particular destination. If the
router receives new routing information from another node, it will overwrite the entry.
RIP maintains optimum routing paths by sending out routing update messages if the network
topology changes. For example, if a router finds that a particular link is faulty, it updates its
routing table and then send a copy of the modified table to each of its neighbors. The neighbors
update their tables with the new information and send updates to their neighbors, and so
on. Within a short period, all routers have the new information