Rip Overview; Rip Working Mechanism - 3Com MSR 50 Series Configuration Manual

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RIP Overview

RIP Working Mechanism

RIP C
ONFIGURATION
When configuring RIP, go to these sections for information you are interested in:
"RIP Overview" on page 971
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"Configuring RIP Basic Functions" on page 976
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"Configuring RIP Advanced Functions" on page 978
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"Optimizing the RIP Network" on page 981
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"Displaying and Maintaining RIP Configuration" on page 986
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"RIP Configuration Example" on page 986
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"Troubleshooting RIP Configuration" on page 990
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RIP is a simple Interior Gateway Protocol (IGP), mainly used in small-sized
networks, such as academic networks and simple structured LANs. RIP is not
applicable to complex networks.
RIP is still widely used in practical networking due to easier implementation,
configuration and maintenance than OSPF and IS-IS.
Basic concept of RIP
RIP is a Distance-Vector (D-V)-based routing protocol, using UDP packets for
exchanging information through port 520.
RIP uses a hop count to measure the distance to a destination. The hop count is
known as metric. The hop count from a router to its directly connected network is
0. The hop count of a network reachable through one router is 1. To limit
convergence time, the range of RIP metric value is from 0 to 15. A metric value of
16 (or bigger) is considered infinite, which means the destination network is
unreachable. That is why RIP is not suitable for large-scaled networks.
RIP prevents routing loops by implementing the split horizon and poison reverse
functions.
RIP routing table
Each RIP router has a routing table containing routing entries of all reachable
destinations, and each routing entry contains:
Destination address: IP address of a host or a network.
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Next hop: IP address of the adjacent router's interface to reach the destination.
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Egress interface: Interface through which the router forwards the packets to
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the destination.
Metric: Cost from the local router to the destination.
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