HALR: A TCP Enhancement Scheme Using Local Caching in High-Availability Cluster

作者：Feng Yi Hsuan^*; Huang Nen Fu; Wu Yen Min

来源：IEICE - Transactions on Communications, 2009, E92B(1): 26-33.

DOI：10.1587/transcom.E92.B.26

• high availability
• TCP enhancement
• modeling
• local loss recovery

In this paper, we study the end-to-end TCP performance over a path deploying a High-Availability cluster, whose characteristics are highlighted by the failover procedure to remove single-point failure. This paper proposes an approach, called High-Availability Local Recovery (HALR), to enhance TCP performance in the face of a cluster failover. To minimize the latency of retransmission, HALR saves TCP packets selectively and resends them locally after the failover is finished. For better understanding, we further develop simple analytic models to predict the TCP performance in the aspect of flow latency under a range of failover times and the effects of HALR. Using simulation results, we validate our models and show that HALR improves the TCP performance significantly over a failover event as compared with the original TCP. Typically., HALR reduces the flow latency from 4.1 see to less than 1.9sec when the failover time equals to 500 ms. The simulation by real packet trace further demonstrates that the memory requirement of the proposed solution is not a concern for modern network equipments.

• 出版日期2009-1
• 单位清华大学