An Algorithm of Enhancing RED Fairness

Random Early Detection (RED) can effectively avoid transmiting congestion at routers, but RED can not provide bandwidth fairness. Different packet sizes are one of the reasons that damage fairness. RED routers provide little protection from some bulky data flows that use considerably more bandwidth than other flows in time of congestion. Modifying the formulas of calculating final packet-discard probability and packet count for RED algorithm based on the sending rate formula of TCP flows, a new algorithm named enhanced-fairness RED (EF-RED) is proposed. Simulation results show that the EF-RED algorithm can efficiently avoid the effect of different packet sizes on TCP bandwidth allocation when congestion takes place, and achieve better bandwidth fairness.