RFC 2080 (rfc2080) - Page 2 of 19
RIPng for IPv6
Alternative Format: Original Text Document
RFC 2080 RIPng for IPv6 January 1997
2.5 Output Processing . . . . . . . . . . . . . . . . . . . . . 14
2.5.1 Triggered Updates . . . . . . . . . . . . . . . . . . . . 14
2.5.2 Generating Response Messages . . . . . . . . . . . . . . . 15
2.6 Split Horizon . . . . . . . . . . . . . . . . . . . . . . . 16
3. Control Functions . . . . . . . . . . . . . . . . . . . . . . 17
4. Security Considerations. . . . . . . . . . . . . . . . . . . . 18
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction
This memo describes one protocol in a series of routing protocols
based on the Bellman-Ford (or distance vector) algorithm. This
algorithm has been used for routing computations in computer networks
since the early days of the ARPANET. The particular packet formats
and protocol described here are based on the program "routed," which
is included with the Berkeley distribution of Unix.
In an international network, such as the Internet, it is very
unlikely that a single routing protocol will used for the entire
network. Rather, the network will be organized as a collection of
Autonomous Systems (AS), each of which will, in general, be
administered by a single entity. Each AS will have its own routing
technology, which may differ among AS's. The routing protocol used
within an AS is referred to as an Interior Gateway Protocol (IGP). A
separate protocol, called an Exterior Gateway Protocol (EGP), is used
to transfer routing information among the AS's. RIPng was designed
to work as an IGP in moderate-size AS's. It is not intended for use
in more complex environments. For information on the context into
which RIP version 1 (RIP-1) is expected to fit, see Braden and Postel
[6].
RIPng is one of a class of algorithms known as Distance Vector
algorithms. The earliest description of this class of algorithms
known to the author is in Ford and Fulkerson [8]. Because of this,
they are sometimes known as Ford-Fulkerson algorithms. The term
Bellman-Ford is also used, and derives from the fact that the
formulation is based on Bellman's equation [4]. The presentation in
this document is closely based on [5]. This document contains a
protocol specification. For an introduction to the mathematics of
routing algorithms, see [1]. The basic algorithms used by this
protocol were used in computer routing as early as 1969 in the
ARPANET. However, the specific ancestry of this protocol is within
the Xerox network protocols. The PUP protocols [7] used the Gateway
Information Protocol to exchange routing information. A somewhat
updated version of this protocol was adopted for the Xerox Network
Systems (XNS) architecture, with the name Routing Information
Protocol [9]. Berkeley's routed is largely the same as the Routing
Malkin & Minnear Standards Track