Configuring RIP for IPv6 – RIPng in Cisco

Last Updated : 28 Oct, 2022

Pre-requisites: Routing Information Protocol (RIP), Routing Information Protocol (RIP) V1 & V2, Implementation of RIP Routing

Routing Information Protocol (RIP) is a dynamic routing protocol that applies hop count as a routing metric to find the best path between source and destination networks. It is a distance vector routing protocol with an AD value of 120 and operates on the network layer of the OSI model. RIP uses port number 520.

RIPng:

RIPng stands for Routing Information Protocol Next Generation. Plain distance-vector protocol utilizing UDP as its transport protocol using port number 521 instead of 520 (to avoid conflict with the existing RIPv1 & RIPv2). Wide adoption of RIP and support over a wide variety of CISCO routers as well as other different vendors prompted the creation of an IPv6 version of RIP called as RIPng. It is built on top of RIPv2 (RIP version 2 for IPv4). The destination IPv6 address for multicast RIPng advertisements is FF02::9. Many operations of RIPng are similar to RIPv2.

METRIC in RIPng:

It is based on hop counts. The metric is incremented by the receiver of RIPng advertisements.

metric =15 being the maximum
metric =16 representing infinity 
(as RIP/ RIPng is suitable for small office
/home office (SOHO) routers and simple networks)

Configure RIPng:

Step 1: Enable IPv6 unicast routing on both routers in global configuration mode :

R1(config)#ipv6 unicast-routing

R2(config)#ipv6 unicast-routing

Step 2: Enable IPv6 on the physical interface fastethernet0/0 :

R1(config)#interface fastethernet0/0
R1(config-if)#ipv6 enable
R1(config-if)#no shut 

R2(config)#interface fastethernet0/0
R2(config-if)#ipv6 enable
R2(config-if)#no shut

Step 3: Configure an IPv6 unicast address on the loopback interface of both routers using the ipv6 address/prefix-length :

R1(config)#interface loopback0
R1(config-if)#ipv6 address 2000:192:168::1/128

R2(config)#interface loopback0
R2(config-if)#ipv6 address 3000:192:168::1/128
$

At this point you will be able to ping the physical interface IPv6 address of the routers but wouldn’t be able to ping the loopback interfaces :

Try pinging R1’s loopback interface through R1 :

R2#ping 2000:192:168::1

This will be the output you will get on the R2 CLI :

So, now configure RIPng on both the routers and will try pinging them again after the configuration :

Step 4: Enabling RIPng on both routers using the ipv6 router rip <name> global configuration command :

R1#ipv6 router rip routing 
R2#ipv6 router rip routing

Step 5: Enable RIP on the physical as well as loopback interface with the ipv6 rip <name> enable interface subcommand on both the routers (where the <name> in this case “routing” matches the ipv6 router rip <name> global configuration command).

R1(config)#interface fastEthernet 0/0
R1(config-if)#ipv6 rip routing enable
R1(config-if)#exit
R1(config)#interface loopback 0
R1(config-if)#ipv6 rip routing enable
R1(config)#do wr

R2(config)#interface fastEthernet 0/0
R2(config-if)#ipv6 rip routing enable
R2(config-if)#exit
R2(config)#interface loopback 0
R2(config-if)#ipv6 rip routing enable
R2(config-if)#exit
R2(config)#do wr

Step 6: Verifying configuration of RIPng on both routers :

R1#show ipv6 protocols

R2#show ipv6 protocols

Checking Connectivity:

Now, try pinging R2’s loopback interface from R1 and vice versa :

R1#ping 3000:192:168::1

R2#ping 2000:192:168::1

R1 will be able to ping the R2 loopback interface after configuring RIPng and vice versa, as RIPng injected route entries of both the routers’ loopback interface IPv6 network in each other’s IPv6 route table through RIPng advertisements (same as RIPv2) :

To capture the interface in GNS3 :