RIPng Protocol Overview

The RIPng IGP uses the Bellman-Ford distance-vector algorithm to determine the best route to a destination, using hop count as the metric. RIPng allows hosts and routers to exchange information for computing routes through an IP-based network. RIPng is intended to act as an IGP for moderately-sized autonomous systems.

RIPng is a distinct routing protocol from RIPv2. The JUNOS software implementation of RIPng is similar to RIPv2, but has the following differences:

• RIPng does not need to implement authentication on packets.
• The JUNOS software does not support multiple instances of RIPng.
• The JUNOS software does not support RIPng routing table groups.

RIPng is a UDP-based protocol and uses UDP port 521.

RIPng has the following architectural limitations:

• The longest network path cannot exceed 15 hops (assuming that each network, or hop, has a cost of 1).
• RIPng is prone to routing loops when the routing tables are reconstructed. Especially when RIPng is implemented in large networks that consist of several hundred routers, RIPng might take extremely long time to resolve routing loops.
• RIPng uses only a fixed metric to select a route. Other IGPs use additional parameters, such as measured delay, reliability, and load.