Overview
Routing Information Protocol version 2 (RIP v2) is defined in RFC 1723 and is supported in IOS versions 11.1 and later. RIP v2 is similar to RIP v1, but is not a new protocol. RIP v2 features extensions to bring it up-to-date with modern routing environments. The RIP v2 extensions are listed in the following:
  • Subnet Masks carried with each route entry
  • Authentication for routing updates
  • Next Hop addressing carried with each route entry
  • Route Tags for external use
  • Queries in response to RIP v1 requests

The most important extension listed is the Subnet Mask field for routing-update entries. The Subnet Mask field enables the use of variable-length subnet masks (VLSMs) and qualifies RIP v2 as a classless routing protocol.

RIP v2 is the first of the classless routing protocols discussed in this module. This module serves as an introduction to classless routing and RIP v2.