Accton Technology ES4626 - Manual (Page 389)

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Switch(config)#ip route 10.1.1.0 255.255.255.0 10.1.2.1
Next hop use the partner IP address
Switch(config)#ip route 10.1.4.0 255.255.255.0 10.1.3.1
Configuration of layer3 SwitchB
Switch#config
Switch(config)#ip route 0.0.0.0 0.0.0.0 10.1.3.2
In this way, ping connectivity can be established between PC-A and PC-C, and PC-B and
PC-C
13.4 RIP
13.4.1 Introduction to RIP
RIP is first introduced in ARPANET, this is a protocol dedicated to small, simple
networks. RIP is a distance vector routing protocol based on the Bellman-Ford algorithm.
Network devices running vector routing protocol send 2 kind of information to the
neighboring devices regularly:
Number of hops to reach the destination network, or metrics to use or number of
networks to pass.
What is the next hop, or the director (vector) to use to reach the destination network.
The distance vector Layer 3 switch send all their route selecting tables to the
neighbor layer3 switches at regular interval. A layer3 switch will build their own route
selecting information table based on the information received from the neighbor layer3
switches. Then, it will send this information to its own neighbor layer3 switches. As a
result, the route selection table is built on second hand information, route beyond 15 hops
will be deemed as unreachable.
RIP protocol is an optional routing protocol based on UDP. Hosts using RIP send and
receive packets on UDP port 520. All layer3 switches running RIP send their route table
to all neighbor layer3 switches every 30 seconds for update. If no information from the
partner is received in 180 seconds, then the device is deemed to have failed and the
network connected to that device is considered to be unreachable. However, the route of
that layer3 switch will be kept in the route table for another 120 seconds before deletion.
As layer3 switches running RIP built route table with second hand information, infinite
count may occur. For a network running RIP routing protocol, when an RIP route
becomes unreachable, the neighboring RIP layer3 switch will not send route update
packets at once, instead, it waits until the update interval timeout (every 30 seconds) and
sends the update packets containing that route. If before it receives the updated packet,
its neighbors send packets containing the information about the failed neighbor, “infinite