On the Effectiveness of CoDel for Active Queue Management

Internet in the present scenario has become a gigantic source of information. There has been a tremendous rise in the variety of Internet applications, with each application demanding a specific performance criteria to be satisfied. Routers presently use Passive Queue Management (PQM) mechanisms and hence, merely have any control over the queue occupancy. Therefore, there has been an increased interest in exploring Active Queue Management (AQM) in Internet routers so as to reduce the queue latency and meet the demands of time sensitive applications. In this paper, we mainly focus on analyzing the effectiveness of a recently proposed AQM mechanism called Controlled Delay (CoDel). We study the effectiveness of CoDel by carrying out simulations in ns-2 and comparing its performance with existing AQM mechanisms in variety of Internet scenarios. Based on the simulation results obtained, we discuss the advantages and shortcomings of CoDel in terms of bottleneck link utilization, mean queue length and packet drop rate.