7.6 RIP and OSPF Redistribution
7.6.1 Case study: configuring a RIP network
This case study is a classic for those making the transition from RIP to OSPF. It has become extremely popular within networking circles. It has been modified and updated slightly, but otherwise the original text and message is identical to when it was a Cisco case study.

This case study addresses the issue of integrating RIP networks with OSPF networks. Most OSPF networks also use RIP to communicate with hosts or to communicate with portions of the internetwork that do not use OSPF.

Cisco supports both the RIP and OSPF protocols and provides a way to exchange routing information between RIP and OSPF networks. This case study provides examples of how to complete the following phases in redistributing information between RIP and OSPF networks:

  • Configuring a RIP network
  • Adding OSPF to the center of a RIP network
  • Adding OSPF areas
  • Setting up mutual distribution

Figure illustrates a RIP network. Three sites are connected with serial lines. The RIP network uses a Class B address and an 8-bit subnet mask. Each site has a contiguous set of network numbers.

Figure lists the network address assignments for the RIP network, including the network number, subnet range, and subnet masks. All interfaces indicate network 130.10.0.0; however, the specific address includes the subnet and subnet mask. For example, serial interface 0 on router C has an IP address of 130.10.63.3 with a subnet mask of 255.255.255.0.

RIP network assignments.

Configuration File Examples

The commands in the configuration file for router A determine the IP address for each interface and enable RIP on those interfaces. (see RouterA#show running-config command output).

The commands in the configuration file for router B determine the IP address for each interface and enable RIP on those interfaces (see RouterB#show running-config command output). 

The commands in the configuration file for router C determine the IP address for each interface and enable RIP on those interfaces. (see RouterC#show running-config command output).