Title :
Random early detection gateways for congestion avoidance
Author :
Floyd, Sally ; Jacobson, Van
Author_Institution :
Lawrence Berkeley Lab., California Univ., Berkeley, CA, USA
fDate :
8/1/1993 12:00:00 AM
Abstract :
The authors present random early detection (RED) gateways for congestion avoidance in packet-switched networks. The gateway detects incipient congestion by computing the average queue size. The gateway could notify connections of congestion either by dropping packets arriving at the gateway or by setting a bit in packet headers. When the average queue size exceeds a present threshold, the gateway drops or marks each arriving packet with a certain probability, where the exact probability is a function of the average queue size. RED gateways keep the average queue size low while allowing occasional bursts of packets in the queue. During congestion, the probability that the gateway notifies a particular connection to reduce its window is roughly proportional to that connection´s share of the bandwidth through the gateway. RED gateways are designed to accompany a transport-layer congestion control protocol such as TCP. The RED gateway has no bias against bursty traffic and avoids the global synchronization of many connections decreasing their window at the same time. Simulations of a TCP/IP network are used to illustrate the performance of RED gateways
Keywords :
internetworking; network servers; packet switching; protocols; queueing theory; TCP; TCP/IP network; average queue size; bandwidth; bursty traffic; congestion avoidance; gateways; packet-switched networks; performance; random early detection; simulations; transport-layer congestion control protocol; Bandwidth; Delay effects; Delay estimation; Feedback; High-speed networks; Propagation delay; TCPIP; Throughput; Traffic control; Transport protocols;
Journal_Title :
Networking, IEEE/ACM Transactions on