Packet Reordering in High-Speed Networks and Its Impact on High-Speed TCP Variants.pdfVIP

Packet Reordering in High-Speed Networks and Its Impact on High-Speed TCP Variants Jie Feng, Zhipeng Ouyang, Lisong Xu, Byrav Ramamurthy Computer Science and Engineering University of Nebraska–Lincoln Lincoln, NE 68588-0115 Email :jfeng,zouyang,xu,byrav @ Abstract— Several recent Internet measurement studies show packet size experiences significantly more reordered packets that the higher the packet sending rate, the higher the packet when its sending rate is higher than 600Mbps. Since high- reordering probability. This implies that recently proposed high- speed TCP variants achieve much higher throughput than speed TCP variants are more likely to experience packet reorder- ing than regular TCP in high-speed networks, since they are regular TCP in high-speed networks, it is highly likely that designed to achieve much higher throughput than regular TCP they will experience more packet reordering than a regular in these networks. In this paper, we study the characteristics of TCP in these networks. packet reordering in high-speed networks, and its impact on high- While there is some debate [4] about whether packet re- speed TCP variants. In addition, we evaluate the effectiveness ordering is a pathological behavior of the Internet, and whether of the existing reordering-tolerant TCP enhancements. Our simulation results demonstrate that high-speed TCP variants this issue should be addressed by designing a reordering- perform poorly in the presence of packet reordering, and free network or by designing a reordering-tol