Variable Length Virtual Output Queue Based Fuzzy Adaptive RED for Congestion Control at Routers

Internet routers play an important role during the time of network congestion. All the Internet routers have some buffer at input and output ports, which hold the packets at the time of congestion. Many queue management algorithms have been proposed but they focus on fixed queue limit. Recognizing the fact that active queue management algorithms have fixed maximum queue limit, we direct our attention to variable length queue limit for Combined Input Output Queued (CIOQ) switches. We incorporated our proposed technique, which is a fuzzy logic control based generic variable length active queue management scheme in TCP/IP networks, to the drop-tail and the Adaptive RED (A-RED) algorithm. The empirical results show low packet loss and high queue utilization in modified algorithms (augmented with variable length active queue management scheme) in comparison to the original droptail, RED and A-RED algorithms.