Browse Prior Art Database

Congestion Control in IP/TCP Internetworks (RFC0896)

IP.com Disclosure Number: IPCOM000003945D
Original Publication Date: 1984-Jan-01
Included in the Prior Art Database: 2019-Feb-13
Document File: 9 page(s) / 17K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

J. Nagle: AUTHOR

Related Documents

10.17487/RFC0896: DOI

Abstract

This memo discusses some aspects of congestion control in IP/TCP Internetworks. It is intended to stimulate thought and further discussion of this topic. While some specific suggestions are made for improved congestion control implementation, this memo does not specify any standards.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 12% of the total text.

Network Working Group John Nagle Request For Comments: 896 6 January 1984 Ford Aerospace and Communications Corporation

Congestion Control in IP/TCP Internetworks

This memo discusses some aspects of congestion control in IP/TCP Internetworks. It is intended to stimulate thought and further discussion of this topic. While some specific suggestions are made for improved congestion control implementation, this memo does not specify any standards.

Introduction

Congestion control is a recognized problem in complex networks. We have discovered that the Department of Defense’s Internet Pro- tocol (IP) , a pure datagram protocol, and Transmission Control Protocol (TCP), a transport layer protocol, when used together, are subject to unusual congestion problems caused by interactions between the transport and datagram layers. In particular, IP gateways are vulnerable to a phenomenon we call "congestion col- lapse", especially when such gateways connect networks of widely different bandwidth. We have developed solutions that prevent congestion collapse.

These problems are not generally recognized because these proto- cols are used most often on networks built on top of ARPANET IMP technology. ARPANET IMP based networks traditionally have uni- form bandwidth and identical switching nodes, and are sized with substantial excess capacity. This excess capacity, and the abil- ity of the IMP system to throttle the transmissions of hosts has for most IP / TCP hosts and networks been adequate to handle congestion. With the recent split of the ARPANET into two inter- connected networks and the growth of other networks with differ- ing properties connected to the ARPANET, however, reliance on the benign properties of the IMP system is no longer enough to allow hosts to communicate rapidly and reliably. Improved handling of congestion is now mandatory for successful network operation under load.

Ford Aerospace and Communications Corporation, and its parent company, Ford Motor Company, operate the only private IP/TCP long-haul network in existence today. This network connects four facilities (one in Michigan, two in California, and one in Eng- land) some with extensive local networks. This net is cross-tied to the ARPANET but uses its own long-haul circuits; traffic between Ford facilities flows over private leased circuits, including a leased transatlantic satellite connection. All switching nodes are pure IP datagram switches with no node-to- node flow control, and all hosts run software either written or heavily modified by Ford or Ford Aerospace. Bandwidth of links in this network varies widely, from 1200 to 10,000,000 bits per second. In general, we have not been able to afford the luxury of excess long-haul bandwidth that the ARPANET possesses, and our long-haul links are heavily loaded during peak periods. Transit times of several seconds are thus common in our network.

RFC 896 Congestion Control in IP/TCP Internetworks 1/6/84

Because of our pure datagram ori...

Processing...
Loading...