In computer networking; the process of moving packets across the network is called routing. The routers are devices that collect the required information about the different network subnets and route packets between these networks. The computer subnets are different ranges of IPs. For example; a computer with the IP address of 10.0.0.1 is in a different network than the computer with the IP address of 172.16.0.1
There are 3 types of network information in the routing table of routers:
- Directly connected routes
- Static Route
- Dynamic routing: RIP, OSPF, EIGRP
Static routing is not Scalable and should be manually configured on the routers. Despite that; the dynamic routing facilitate the network administration by configuring the routers to talk to each other and share the information that they have about the networks around them.
RIP v1 VS RIP v2
- RIP(Routing Information Protocol) is the simplest dynamic routing protocol to configure on the routers. RIP has some limitations as well. RIP is a distance vector routing protocol. The routing updates are sent every 30 seconds.
- RIP uses hop-count metric
- RIP can load balance across a maximum of six paths – default to four paths
- RIP v2 supports authentication
- RIP does not distinguish the speed and reliability of the links, just the hop-count
- Maximum hop-count is 15
- Hop-count of 16 will be considered unreachable
- RIP v1: Classful routing protocol, No VLSM support, No Authentication support, Advertisements are sent as broadcasts
- RIP V2: Classless routing protocol, VLSM support, Plain text or D5 authentication support, Advertisements sent as multicasts
More related information:
- Split horizon: RIP will not advertise a network out from the same interface that it learned the route from.
- Split horizon will prevent routing loops.
- Loopback interface is an interface that never goes down unless we shut it down. We can go to router A and ping the IP address of loop back interface of router B (troubleshooting using loopback interface).
Here are some useful commands in configuring RIP:
- Config# router rip
- Config-router# network ip-address
- Config-router# version 2
- Config-router# no auto-summary (Disables automatic summarization for RIPv2- RIP v1 always uses this command)
- Config-if# ip rip send version 1|2
- Config-if# ip rip receive version 1|2
- Config-if# ip rip authentication mode text|MD5
- Config# key chain name
- Config-keychain# key number
- Config-keychain-key# key-string string
#show ip route (Demonstrates all the routes that the routers recognizes)