3Com 4510G, Руководство по настройке

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RIP Configuration
The term “router” in this document refers to a router in a generic sense or a Layer 3 switch.
When configuring RIP, go to these sections for information you are interested in:
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RIP Overview
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Configuring RIP Basic Functions
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Configuring RIP Route Control
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Configuring RIP Network Optimization
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Displaying and Maintaining RIP
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RIP Configuration Examples
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Troubleshooting RIP
RIP Overview
RIP is a simple Interior Gateway Protocol (IGP), mainly used in small-sized networks, such as
academic networks and simple 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.
Operation of RIP
Introduction
RIP is a distance vector 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 from a router to a
directly connected network is 0. The hop count from a router to a directly connected router is 1. To limit
convergence time, the range of RIP metric value is from 0 to 15. A metric value of 16 (or greater) 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
A RIP router has a routing table containing routing entries of all reachable destinations, and each
routing entry contains:
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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.