Chapter 5 Avaya P460 Layer 3 Features
46 Avaya P460 Configuration Guide
RIP (Routing Interchange Protocol) ConfigurationRIP Overview
RIP is one of the two main groups of routing protocols - the other is OSPF (refer to
"OSPF Overview" on page 49 for details). It is a “distance vector protocol” – the
router decides which path to use on distance or the number o f interm ediate ho ps. In
order for this protocol to work correctly, all the routers – and possibly the nodes –
need to gather information on how to reach each destination in the Internet. The
very simplicity of RIP has a disadvantage however: this protocol does not take into
account he network bandwidth, physical cost, data priority, and so on.
The P460 supports the widely used RIP routing protocol – both RIPv1 and RIPv2.
The RIPv1 protocol imposes some limitations on the network design with regard to
subnetting. When operating RIPv1, you must not configure variable length
subnetwork masks (VLMS). Each IP network must have a single mask, implying
that all subnetworks in a given IP network are of the same size. Also, when
operating RIPv1, you must not configure supernets. These are networks with a
mask smaller than the natural net mask of the address class, such as 192.1.0.0 with
mask 255.255.0.0, smaller than the natural class C mask which is 255.255.255.0. For
detailed descriptions of RIP refer to the standards and published literature.
RIPv2 is a new version of the RIP routing protocol but with some advantages over
RIPv1. RIPv2 solves some of the problems associated with RIPv1. The most
important change in RIPv2 is the addition of a subnetwork mask field which allows
RIPv2 to support variable length subnetworks. RIPv2 also includes an
authentication mechanism similar to the one used in OSPF.
Configuration of the RIP version, 1 or 2, is per IP interface. Configuration must be
homogenous on all routers on each subnetwork, that is, there should not be both
RIPv1 and RIPv2 routers on the same subnetwork. However, you can configure
different IP interfaces of the P460 with different RIP versions. This configuration is
valid as long as all routers on the subnet are configured to the same version.
RIPv2 and RIPv1 are considered the same protocol with regard to redistribution to/
from OSPF and static route preferences.
The Avaya P460 supports both RIPv1 and RIPv2 in Router mode.