A delay-based analysis of multiple bottleneck links of end-to-end paths in the internet

Measurement and analysis of bottleneck links play an important role in improving the network quality of service (QoS) and preventing network attacks in the Internet. Existing methods usually treat the link with the smallest available bandwidth or the largest delay as the bottleneck link, without considering multiple bottleneck links in an end-to-end path. In this paper, we propose a new approach to measure and analyze bottleneck links based on path delay. We design a parallel active measurement framework to measure the path delays of many destinations simultaneously. Then an algorithm to identify multiple bottleneck links is proposed using the Ward data clustering method. Experiments are conducted to test the algorithm by measuring 10 different destinations in the Internet for 14 days. Using the proposed approach, we have found that bottleneck links are mainly few constant links which are in the intermediate of end-to-end paths or near the destinations. Furthermore, the results have shown that the number of intra-domain bottleneck links takes a large portion in most cases, which hints that the performance of end-to-end paths may be greatly influenced by iBGP routing. Besides, the results have also demonstrated that the intercontinental links in an anonymous system (AS) incline to be bottleneck links in end-to-end paths.