VRED: An improvement over RED algorithm by using queue length growth velocity


1 Computer Engineering Department, University of MohagheghArdabili, Ardabil, Iran

2 Department of Computer Engineering, Zanjan Branch, Islamic Azad University, Zanjan, Iran

3 Sama technical and vocational training college, Islamic Azad University,Ardabil Branch, Ardabil, Iran


Active Queue Management (AQM) plays an important role in the Internet congestion control. It tries to enhance congestion control, and to achieve tradeoff between bottleneck utilization and delay. Random Early Detection (RED) is the most popular active queue management algorithm that has been implemented in the in Internet routers and is trying to supply low delay and low packet loss. RED algorithm uses only the average queue length as a congestion meter to trigger packet dropping or packet marking as a congestion feedback. Since the average queue length considers only long–term behavior of any queue, this approach fails to see instantaneous changes of the queue length and hence its reaction is not fast enough. This paperincludes another meter i.e. queue length growth velocity to measure congestion level in the router. This leads to fast reaction to the congestion and hence improves the network performance. Simulation results show that the proposed algorithm outperforms RED algorithm in terms of number of dropped packets and bottleneck utilization.