Fuzzy Logic Congestion Control in TCP/IP Best-Effort Networks

This paper presents a new active queue management (AQM) scheme -Fuzzy Explicit Marking (FEM)supporting explicit congestion notification (ECN), to provide congestion control in TCP/IP besteffort networks using a fuzzy logic control approach. While many AQM mechanisms have recently been proposed, these require careful configuration of nonintuitive control parameters, and show weaknesses to detect and control congestion under dynamic traffic changes, and a slow response to regulate queues. The proposed fuzzy logic approach for congestion control allows the use of linguistic knowledge to capture the dynamics of nonlinear probability marking functions, uses multiple inputs to capture the (dynamic) state of the network more accurately, and can offer effective implementation. A simulation study over a wide range of traffic conditions shows that the FEM controller outperforms a number of representative AQM schemes in terms of queue fluctuations and delays, packet losses, and link utilization.