多路径数据传输中的可用带宽测量算法研究

A Measurement Algorithm of Available Bandwidth in Multi-path Transmission

在分布式中转服务器网络辅助的多路径数据传输系统中,为获得最快的数据传输速率,需要使用可用带宽测量技术以获得数据发送端至各中转服务器的可用带宽值列表。然而,传统的可用带宽测量算法难以同时兼顾测量精度与收敛速度,故无法达到实际数据传输系统中准确快速完成维护可用带宽值列表的目的。为解决上述问题,提出了一种可用带宽测量算法。通过收集初始探测流的包对在发送端及接收端的时间间隔关系数据获得可用带宽估测值,再以此值为后续探测流的发送速率初始值,通过自适应方法调整探测流发送速率以逐渐逼近可用带宽真实值。实验结果表明,改进算法能快速获得高精度的测量结果,有效提升可用带宽的测量效率,满足数据传输系统的需求。

In order to obtain maximum transmission rate in distributed transfer servers＇ network assisted multipath transmission system, a list of transfer servers that have maximum transmission rate with the sender is needed via available bandwidth measurement techniques. However, traditional available bandwidth measurement algorithm can hardly ensure convergence rate and accuracy simultaneously. An available bandwidth measurement algorithm is proposed to solve this problem. The interval time of packets＇ pairs are used to estimate the available bandwidth value in the initial probing stream. Based on the value, we adjust the transmission rate to gradually approach true value of current available bandwidth adaptively. The simulation result shows that this algorithm has high convergence rate and high accuracy, thus it improves the measurement of available bandwidth effectively and meets the requirements of the multi-path transmission system.