Browse Prior Art Database

CONGESTION MANAGEMENT PROTOCOL FOR CONNECTIONLESS PACKET NETWORKS

IP.com Disclosure Number: IPCOM000008318D
Original Publication Date: 1997-Sep-01
Included in the Prior Art Database: 2002-Jun-05
Document File: 3 page(s) / 176K

Publishing Venue

Motorola

Related People

Paula Tjandra: AUTHOR [+2]

Abstract

This paper introduces a congestion management protocol for connectionless packet networks. Congestion in connectionless packet network environment is often related to the shared band- width within a cell boundary where bandwidth is shared between multiple users. By effectively capitalizing this information, the network can achieve throughput and higher level of user data security. Our proposal is based on the supposition that the protocols at the network (IP) layer and above will not be modified.

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MOTOROLA Technical Developments

CONGESTION MANAGEMENT PROTOCOL FOR CONNECTIONLESS PACKET NETWORKS

by Paula Tjandra and Tomas Capurka

ABSTRACT

  This paper introduces a congestion management protocol for connectionless packet networks. Congestion in connectionless packet network environment is often related to the shared band- width within a cell boundary where bandwidth is shared between multiple users. By effectively capitalizing this information, the network can achieve throughput and higher level of user data security. Our proposal is based on the supposition that the protocols at the network (IP) layer and above will not be modified.

INTRODUCTION

  Network security and bandwidth limitations have created a demand for user data encryption and compression functionality in data communication services. Data compression and stream type encryption functions require an underlying data link service which provides a reliable connection. In case of data loss the release of data layer connection is used as an indication to resynchronize the encryption key and the compression dictionaries at both end points.

  Frequent datagram loss results in frequent initialization of the encryption key and the compression dictionaries. Unfortunately the security level of encryption for, a stream type encryption algorithm decreases with the increase in the number of resynchronizations of the encryption algorithm. Also, the performance of a compression algorithm is greatly reduced as the number of resynchroniza- tions of the compression dictionary increases. Moreover, resynchronization requires reestablish- ment of data link layer which causes overhead in bandwidth usage for establishment messages between the two end points.

  In current packet data systems the compression, encryption and link layers do not take into consider- ation that congestion is often related to the shared bandwidth within a cell boundary. When the packet data network protocol is IP, congestion problems are handled by dropping of packets. When transport layer protocol TCP is used in conjunction with IP, packet losses are interpreted as an indication of congestion. However, when the congestion occurs at the cell level, the packets must be dropped at the link layer, resetting encryption and compression causing the negative impacts mentioned above.

  In CDPD', a packet data system which is already available in market, cell level congestion results in data link layer transmission error. This also forces the encryption key and compression dictionary to be initialized. Multiple users at a con- gested cell will experience the impact of frequent resynchronization.

  This paper proposes adding a congestion management protocol (CMP) below the IP layer and above the encryption/compression layer. The purpose of CMP is to decrease the number resynchronization caused by data loss.

DESCRIPTION

CONNECTIONLESS PACKET NETWORK MODEL

  A logical view of the underlying connectionless packet network and the manner...