RFC 1139 (rfc1139) - Page 1 of 6
Echo function for ISO 8473
Alternative Format: Original Text Document
Network Working Group IETF-OSI Working Group
Request for Comments: 1139 R. Hagens
January 1990
An Echo Function for ISO 8473
Status of this Memo
This memo defines an echo function for the connection-less network
layer protocol. This memo is not intended to compete with an ISO
standard. This is a Proposed Elective Standard for the Internet.
Distribution of this memo is unlimited.
Abstract
This memo defines an echo function for the connection-less network
layer protocol. Two mechanisms are introduced that may be used to
implement the echo function. The first mechanism is recommended as
an interim solution for the Internet community. The second mechanism
will be progressed to the ANSI X3S3.3 working group for consideration
as a work item.
When an ISO standard is adopted that provides functionality similar
to that described by this memo, then this memo will become obsolete
and superceded by the ISO standard.
1. Introduction
The OSI Connection-less network layer protocol (ISO 8473) defines a
means for transmitting and relaying data and error report PDUs
through an OSI internet. Unfortunately, the world that these packets
travel through is imperfect. Gateways and links may fail. This memo
defines an echo function to be used in the debugging and testing of
the OSI network layer.
Network management protocols can be used to determine the state of a
gateway or link. However, since these protocols themselves utilize a
protocol that may experience packet loss, it cannot be guaranteed
that the network management applications can be utilized. A simple
mechanism in the network layer is required so that systems can be
probed to determine if the lowest levels of the networking software
are operating correctly. This mechanism is not intended to compete
with or replace network management; rather it should be viewed as an
addition to the facilities offered by network management.
There are three important issues to consider when defining an echo
extension to ISO 8473: complexity, code-path divergence, and backward
IETF-OSI Working Group