CHOKe with Recent Drop History

Abstract

This paper proposes a new Active Queue Management (AQM) technique, called CHOKe-RH (CHOKe with Recent Drop History), to achieve congestion control in the network and to protect TCP responsive flows from unresponsive flows. CHOKe-RH retains the good features of RED and CHOKe, such as the low processing cost, while overcomes their limitations. CHOKe-RH upholds the simplicity principle of the Internet design and does not require per-flow information for its processing. It improves the match-drop technique of CHOKe. It performs multiple comparisons which consist of two parts: i) initial comparisons, and ii) penalty for unresponsive flows. The initial number of comparisons is set to 3 and the penalty for unresponsive flows is adjusted dynamically depending on the average queue size. CHOKe-RH maintains the history of recently dropped packets by storing their flow-ids and uses this history for penalizing the aggressive unresponsive flows. The performance of CHOKe-RH is analyzed through ns2 simulations in different network scenarios and is compared with the well-known techniques like RED, CHOKe and CHOKeR. The results demonstrate that CHOKe-RH punishes the unresponsive flows very effectively and ensures better fairness among different flows.