Measuring Capacity Bandwidth of Targeted Path Segments

Accurate measurement of network bandwidth is important for network management applications as well as flexible Internet applications and protocols which actively manage and dynamically adapt to changing utilization of network resources. Extensive work has focused on two approaches to measuring bandwidth: measuring it hop-by-hop, and measuring it end-to-end along a path. Unfortunately, best-practice techniques for the former are inefficient and techniques for the latter are only able to observe bottlenecks visible at end-to-end scope. In this paper, we develop end-to-end probing methods which can measure bottleneck capacity bandwidth along arbitrary, targeted subpaths of a path in the network, including subpaths shared by a set of flows. We evaluate our technique through ns simulations, then provide a comparative Internet performance evaluation against hop-by-hop and end-to-end techniques. We also describe a number of applications which we foresee as standing to benefit from solutions to this problem, ranging from network troubleshooting and capacity provisioning to optimizing the layout of application-level overlay networks, to optimized replica placement.