Survey of Bandwidth Estimation Techniques

The ability to locate bottleneck link along Internet paths is of great interest to end users as well as network operators. End users can use the information to estimate performance of a network path to a given destination. The knowledge of bottlenecks can provide network operators insight into the causes of congestion and ways of circumventing it. Flows that share a common bottleneck resource can benefit from cooperative congestion control strategies ([16]). Due to the intriguing nature of the problem and its practical importance, a number of techniques as well as tools have been proposed to measure bandwidth on Internet paths. In this paper we survey a large number of publicly available tools and techniques to estimate bandwidth in stub networks. We found that although there are some tools available that can be adapted to meet our requirement, these tools do not give consistent performance. We therefore devise a simple strategy that provides an upper bound to the estimation results. Our scheme ensures that the results of these tools do not stray beyond acceptable limits. The methodology was validated in actual Internet paths.