GREEN: proactive queue management over a best-effort network

Abstract

We present a proactive queue-management (PQM) algorithm called GREEN (generalized random early evasion network) that applies knowledge of the steady-state behavior of TCP connections to drop packets intelligently and proactively, thus preventing congestion from ever occurring and ensuring a higher degree of fairness between flows. This congestion-prevention approach is in contrast to the congestion-avoidance approach of traditional active queue-management (AQM) schemes where congestion is actively detected early and then reacted to. In addition to enhancing fairness, GREEN keeps packet-queue lengths relatively low and reduces bandwidth and latency jitter. These characteristics are particularly beneficial to real-time multimedia applications. Further, GREEN achieves the above while maintaining high link utilization and low packet loss.