Browse Prior Art Database

Traffic Control in Packet Switched Networks

IP.com Disclosure Number: IPCOM000084593D
Original Publication Date: 1975-Dec-01
Included in the Prior Art Database: 2005-Mar-02
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Friedman, SW: AUTHOR [+3]

Abstract

In packet switched data communication networks--organized for multinodal store and forward exchange switching of data messages in a multibit packet segment--congestion due to overloading of nodal storage and channel facilities can be efficiently eased, by selectively blocking transfers of "uncommitted" traffic and preferentially transferring only "committed" traffic through the congested facilities.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 65% of the total text.

Page 1 of 1

Traffic Control in Packet Switched Networks

In packet switched data communication networks--organized for multinodal store and forward exchange switching of data messages in a multibit packet segment--congestion due to overloading of nodal storage and channel facilities can be efficiently eased, by selectively blocking transfers of "uncommitted" traffic and preferentially transferring only "committed" traffic through the congested facilities.

It is possible to compute by heuristic techniques, the expected (or idealized) number of intervening nodes each packet should encounter in transit through the network. By attaching to each packet header count parameters which indicate both this expected number and the number of nodes actually traversed by the respective packet, a measure of "commitment" is given to the nodal facility presently handling that packet. This can be used as the basis for deciding logically whether to pass or block that packet. Thus, during congestion, a packet transferred over less than 40% of the total anticipated path may be treated as uncommitted and blocked. Conversely, a packet transferred over more than 40% may be treated as committed and given preferential "pass" handling.

The criterion employed for selection can be variably tuned to the degree of congestion (assuming that measures of degrees of congestion can be calculated and represented).

The effect of such pass/block selection is to "throttle" traffic just entering the ""congested'' net...