3Com Switch 7757, Руководство по настройке

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290 C
HAPTER
33: RIP C
ONFIGURATION
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Garbage-collection timer: An unreachable route will be completely deleted
from the routing table if no update packet for the route is received from the
neighbor before this timer times out.
RIP Startup and
Operation
The whole process of RIP startup and operation is as follows:
■
Once RIP is enabled on a router, the router broadcasts or multicasts a request
packet to its neighbors. Upon receiving the packet, each neighbor running RIP
answers a response packet containing its routing table information.
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When this router receives a response packet, it modifies its local routing table
and sends an update triggering packet to the neighbor. Upon receiving the
update triggering packet, the neighbor sends the packet to all its neighbors.
After a series of update triggering processes, each router can get and keep the
updated routing information.
■
By default, RIP sends its routing table to its neighbors every 30 seconds. Upon
receiving the packets, the neighbors maintain their own routing tables and
select optimal routes, and then advertise update information to their respective
neighbors so as to make the updated routes known globally. Furthermore, RIP
uses the timeout mechanism to handle the timeout routes so as to ensure
real-time and valid routes.
RIP is commonly used by most IP router suppliers. It can be used in most campus
networks and the regional networks that are simple and less dispersive. For larger
and more complicated networks, RIP is not recommended.
Introduction to RIP
Configuration Tasks
Table 213 RIP configuration tasks
Configuration Task Description Related section
Configuring Basic RIP
Functions Enabling RIP globally
and on the interface of
a specified network
segment Required “Enabling RIP
globally and on the
interface of a
specified network
segment” on page
292
Setting the RIP
operating status on an
interface Optional “Setting the RIP
operating status on
an interface” on
page 292
Specifying the RIP
version on an interface Optional “Specifying the RIP
version on an
interface” on page
292