Active Queue Management in EGPRS

Active queue management (AQM) schemes such as random early detection (RED) or explicit congestion notification (ECN) for TCP-based traffic are important components of the general packet radio service (GPRS) system performance because of potential traffic bottlenecks caused by, e.g., limited radio capacity. Poorly implemented or configured AQM may lead to intolerable end-to-end buffer delays in the serving GPRS support node (2G-SGSN) as well as reduced overall throughput when the system load increases. Although the usefulness of AQM in the fixed Internet is well known, the need for adequate AQM in GPRS or enhanced GPRS (EGPRS) has not been much documented. In this paper, we evaluate the performance of various AQM schemes by means of simulations and we show that RED and ECN are among the most efficient for reducing buffer delay and improving overall end-user experience