ALL ABOUT RIP

ALL ABOUT RIP

1. RIP stands for Routing Information Protocol.

2. It is an Interior Gateway Distance Vector routing protocol.

3. RIP protocol is based on Bellman-ford algorithm.

4. It uses Hop count matrix to calculate best route for sending data from one network to another

5. Maximum hop count limit is 15 hops, 16th hop will be unreachable.

6. Administrative Distance (AD) value of RIP is 120. 
7. It uses port number UDP 520 to carry data.

RIP VERSIONS

There are two versions of RIP, they are:

1. RIP version 1

2. RIP version 2

RIPv1

1. It broadcasts routing table. (broadcast address=255.255.255.255) 

2. It sends periodic updates     (default time= 30 seconds)

3. It supports only class-full IP addresses.

4. It does not supports authentication and discontinuous networks.

RIPv2

1. It multicasts routing table. (multicast address=224.0.0.9)

2. It sends triggered updates  (When there is a change in network)

3. It supports both class-full and classless IP

4. It supports VLSM and CIDR (classless Inter Domain Routing)

5. It also supports authentication and discontinuous networks.

6. RIP protocol uses port number UDP 520 to carry data.

RIP TIMERS

1. Route Update Timer (30 seconds)

2. Route Invalid Timer  (180 seconds)

3. Hold Down Timer      (180 seconds)

4. Flush Timer              (240 seconds)

1. Route Update Timer

Route update timer is an interval at which router sends it routing information to it's neighbors. default time is 30 seconds.

2. Route Invalid Timer

Route Invalid timer specifies how long a routing entry can be in the routing table without being updated. It is also known as expiration timer. default time is 180 seconds. router sets routing entry of that network to 16 means destination is unreachable if it does not receive any update of that network in 180 seconds. 

2. Hold down Timer

Hold down timer specifies the time in seconds that router waits before accept any new update for the route that in hold down. default time is 180 seconds. 

2. Flush Timer

Flush timer specifies the time at which router removes the route entry from it's routing table if there is no new update of that route. default time is 240 seconds.

To show timer's detail

Router# show ip protocols

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Router Protocol is "RIP"

Sending updates every 30 seconds, next due in 16 seconds

Invalid after 180 seconds, hold down 180, flushed after 240

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To change RIP timers

Router(config)# router rip

Router(config-router)# timer basic 40  190  190  250

where first is update timer (40 seconds), second is invalid timer (190 seconds), third is hold down timer (190 seconds), and forth is flush timer ( 250 seconds)

Routing Steps

Router1(config)# router rip

Router1(config-router)# network 10.0.0.0                    (connected network)

Router1(config-router)# network 40.0.0.0                    (connected network)

Router1(config-router)# end

Router1# write

Router2(config)# router rip

Router2(config-router)# network 40.0.0.0                    (connected network)

Router2(config-router)# network 50.0.0.0                    (connected network)

Router2(config-router)# network 20.0.0.0                    (connected network)

Router2(config-router)# end

Router2# write

Router3(config)# router rip

Router3(config-router)# network 50.0.0.0                    (connected network)

Router3(config-router)# network 30.0.0.0                    (connected network)

Router3(config-router)# end

Router3# write

To show routing table

Router# show ip route