Configuring RIPv1

Objectives

• Encounter and describe the limitations of RIPv1’s limitations.

• Apply the basic Routing Information Protocol Version 2 (RIPv2) configuration commands and evaluate RIPv2 classless routing updates.

• Analyze router output to see RIPv2 support for VLSM and CIDR

• Identify RIPv2 verification commands and common RIPv2 issues.

• Configure, verify, and troubleshoot RIPv2 in “handson” labs

Introduction 

• Chapter focus
• Difference between RIPv1 & RIPv2

• RIPv1
• A classful distance vector routing protocol
• Does not support discontiguous subnets
• Does not support VLSM 
• Does not send subnet mask in routing update
• Routing updates are broadcast

• RIPv2
• A classless distance vector routing protocol that is an enhancement of RIPv1’s features.
• Next hop address is included in updates
• Routing updates are multicast
• The use of authentication is an option 
• Similarities between RIPv1 & RIPv2
• Use of timers to prevent routing loops
• Use of split horizon or split horizon with poison reverse
• Use of triggered updates
• Maximum hop count of 15

RIPv1 Limitations

• Lab Topology
• Scenario:
• 3 router set up
• Topology is discontiguous
• There exists a static summary route
• Static route information can be injected into routing table updates using redistribution.
• Routers 1 & 3 contain VLSM networks

• Scenario Continued

• VLSM
• Recall this is sub netting the subnet

• Private IP addresses are on LAN links

• Public IP addresses are used on WAN links

• Loopback interfaces
• These are virtual interfaces that can be pinged and added to routing table

• Null Interfaces

• This is a virtual interface that does not need to be created or configured
• Traffic sent to a null interface is discarded
• Null interfaces do not send or receive traffic

• Static routes and null interfaces
• null interfaces will serve as the exit interface for static route
• Example of configuring a static supernet route with a null interface
• R2(config)#ip route 192.168.0.0 255.255.0.0 Null0

• Route redistribution
• Redistribution command is way to disseminate a static route from one router to another via a routing protocol
• Example R2(config-router)#redistribute static

• Verifying and Testing Connectivity Use the following commands:
• show ip interfaces brief
• ping
• traceroute

• RIPv1 – a classful routing protocol

• Subnet mask are not sent in updates
• Summarizes networks at major network boundaries
• if network is discontiguous and RIPv1 configured convergence will not be reached

•  Examining the routing tables
• To examine the contents of routing updates use the debug ip rip command
• If RIPv1 is configured then Subnet masks will not be included with the network address

• RIPv1 does not support VLSM Reason: RIPv1 does not send subnet mask in routing updates

• RIPv1 does summarize routes to the Classful boundary Or uses the Subnet mask of the outgoing interface to determine which subnets to advertise

• No CIDR Support

• In the diagram R2 will not include the static route in its update Reason: Classful routing protocols do not support CIDR routes that are summarized with a smaller mask than the classful subnet mask