TCP and UDP performance for Internet over optical packet-switched networks

A strong candidate for the future Internet core is optical packet-switched (OPS) network. In this paper, we study the impact of mechanisms as employed in OPS networks on the performance of upper layer Internet protocols represented by TCP and UDP. The mechanisms we investigate are packet aggregation, deflection routing, and ingress buffering. We show that packet aggregation in general improves TCP throughput, and the improvement increases with the aggregation interval (or optical packet size). With the packets destined to the same egress optical switch, aggregation may be done at different granularities: aggregating all the packets (full aggregation), aggregating packets from the same traffic class (per-class aggregation), and aggregating packets from the same flow (per-flow aggregation). We show that with perclass aggregation and per-flow aggregation some flows may be severely penalized in throughput at large aggregation intervals, resulting in significant degradation in TCP fairness...

• Type: Journal
• Year: 2004
• Where: CN
• Authors: Jingyi He, S.-H. Gary Chan
• Keywords: CN 2004, Packet Aggregation, Per-flow Aggregation, Throughput