Congestion control in differentiated services networks using Fuzzy-RED

Abstract

Network congestion control remains a critical and high priority issue. The rapid growth of the Internet and increased demand to use the Internet for time-sensitive voice and video applications necessitate the design and utilization of effective congestion control algorithms, especially for new architectures, such as differentiated services (Diff-Serv). As a result, a number of researchers are now looking at alternative schemes to TCP congestion control. Random early detection (RED) and its variants are one of these alternatives to provide quality of service (QoS) in TCP/IP Diff-Serv networks. In this paper, we present the results of a fuzzy logic control approach to RED implementation, Fuzzy-RED, implemented within the Diff-Serv framework. The proposed fuzzy logic approach for congestion control allows the use of linguistic knowledge to capture the dynamics of non-linear probability discard functions and offer more effective implementation, use multiple inputs to capture the (dynamic) state of the network more accurately, enable finer tuning for packet discarding behaviors for aggregated flows, and thus provide better QoS to different types of data streams, such as TCP/FTP traffic or TCP/Web-like traffic, whilst maintaining high utilization. © 2003 Elsevier Ltd. All rights reserved.