A quality measurement tool for high-speed data transfer in long fat networks

Due to rapid increase of network bandwidth, applications and systems working in long fat network (LFN) play more important roles. For effective development of them, precise measurements of network conditions are significant. Transmission Control Protocol (TCP) is the most commonly used protocol, but is essentially unable to achieve high throughput in LFNs with packet losses. For this reason, it is hard for conventional network measurement tools to show the maximum or available bandwidth in LFN, especially in high packet loss environments. To overcome this issue, we introduce a novel data transfer protocol on TCP/IP transport layer, namely high-performance and flexible protocol (HpFP). For high-precision pace control and retransmission control, the HpFP intermittently monitors network conditions such as packet loss and latency. We develop an application via the HpFP, named hperf, which measures end-to-end throughput as well as status of packet loss and latency in LFNs. We carry out experiments to examine the abilities of the hperf in high-throughput data transfer and measurement of network qualities in terms of packet loss and latency. The hperf achieves almost wire-rate throughput, 10 Gbps, on the international link between Japan and the USA with even 0.5% packet loss ratio (PLR). The measurements of packet loss and latency show good correspondence with the conventional methods via iperf and ping. These results are verified in our laboratory experiments on 10 Gbps link using a network simulator as well. We conclude that the HpFP has significant potential for a variety of network applications and the hperf is a good network quality measurement tool in LFNs, compared to the conventional TCPs.