Quantitative Adaptive RED in Differentiated Service Networks

This paper derives a quantitative model between RED (Random Early Detection) maxp and committed traffic rate for token-based marking schemes in DiffServ IP networks. Then, a DiffServ Quantitative RED (DQRED) is presented, which can adapt its dropping probability to marking probability of the edge router to reflect not only the sharing bandwidth but also the requirement of performance of these services. Hence, DQRED can cooperate with marking schemes to guarantee fairness between different DiffServ AF class services. A new marking probability metering algorithm is also proposed to cooperate with DQRED. Simulation results verify that DQRED mechanism can not only control congestion of DiffServ network very well, but also satisfy different quality requirements of AF class service. The performance of DQRED is better than that of WRED.