Internet中支配延迟的特征行为研究

Research on the Characteristic Behavior of Internet Dominant Delay

通过对CAIDA机构授权的原始海量样本数据处理得到单向链路延迟,在此基础上计算了路径上最大的链路延迟对端到端延迟的比例以及路径上链路个数分布,基于此定义了支配延迟.针对链路延迟对端到端延迟的影响进行分析,表明支配延迟之间的差异是导致端到端延迟呈现多峰分布的主要原因.支配延迟更多地出现在路径的中间部分和AS自治域内部,说明延迟瓶颈从网络的接入部分向传输部分转移,得出传输延迟在总延迟中的影响逐渐减小,路径中的支配延迟将主要由传播延迟决定的结论.

By dealing with the raw giant data samples authorized by CAIDA, we obtain one-way link delay. Together with the ratio of the biggest link delay to the end-to-end delay and the distribution of the Intemet hops, the dominant delay is defined. Analysis on the impact of link delay on the end-to-end delay reviews that discrepancy of dominant delay primarily accounts for the multi-modal distribution of end-to-end delay. Besides, dominant delay tends to position more preferentially on the middle part of paths and inside the AS, which indicates that the delay bottleneck was shifted from access part to transmission part. At last, conclusion is draw that propagation delay is the major composition of the dominant delay as the effect of transmission delay declined.