Performance analysis of congestion control mechanism using queue thresholds under bursty traffic

Performance modeling and analysis of the Internet Traffic Congestion control mechanism has become one of the most critical issues. Several approaches have been proposed in the literature by using queue thresholds. This motivates the analysis of a discrete-time finite capacity queue with thresholds to control the congestion caused by the bursy traffic. The maximum entropy (ME) methodology has been used to characterize the closed form expressions for the state and blocking probabilities. A GGeo/GGeo/1/[N-1, N-2) censored queue with external compound Bernoulli traffic process and generalised geometric transmission times under a first come first serve (FCFS) rule and arrival first (AF) buffer management policy for single class jobs has been used for the solution process. To satisfy the low delay along with high throughput, a threshold, N-1, has been incorporated to slow the arrival process from mean arrival rate lambda(1), to lambda(2) once the queue length has been reached up to the threshold value N-1 (N-2 is the total capacity of the queue). The source operates normally, otherwise. This is like an implicit feedback from the queue to the arrival process. The system can be potentially used as a model for congestion control based on Random Early Detection (RED) mechanism. Typical numerical results have been presented to show the credibility of ME solution and its validation against simulation.