Applied Mathematics & Information Sciences

Author Country (or Countries)



Queue management is critical for high-performance and high-speed routers. Pushout scheme (PO) performs well in terms of buffer utilization and packet loss probability, but requires identifying the longest flow queue and executing frequent pushout operations whenever a packet arrives at a full buffer. Additionally, PO cannot effectively protect lightly loaded flows against bandwidth aggression from heavily loaded flows under bursty traffic conditions. To overcome the disadvantages of the PO, this study proposes a simple but efficient queue management scheme, namely pushout with differentiated dropping (PDD). PDD uses a weight function to estimate the weights of active flows based on their traffic intensity; moreover, it maintains the flow states of two approximate maximum and submaximum differentiated factors. By comparing differentiated factors of arriving packets with both maintained differentiated factors, PDD can correctly deal with each arriving packet by discard, pushout or acceptance. Simulation results verify that PDD has better fair bandwidth sharing and much lower packet pushout probability than PO under a variety of traffic conditions.