Preemptive Packet-Mode Scheduling to Improve TCP Performance
نویسندگان
چکیده
Recent Internet traffic measurements show that 60% of the total packets are short packets, which include TCP acknowledgment and control segments. These short packets make a great impact on the performance of TCP. Unfortunately, short packets suffer from large delay due to serving long data packets in switches running in the packet mode, i.e. a packet is switched in its entirety. To optimize TCP performance, we apply a cross-layer approach to the design of switching architectures and scheduling algorithms. Specifically, we propose a preemptive packet-mode scheduling architecture and an algorithm called preemptive short packets first (P-SPF). Analysis and simulation results demonstrate that compared to existing packet-mode schedulers, P-SPF significantly reduces the waiting time for short packets while achieving a high overall throughput when the traffic load is heavy. Moreover, with a relatively low speedup, P-SPF performs better than existing packet-mode schedulers under any traffic load.
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