| Measuring the link bandwidth along a path is important for many applications. Some applications can adapt their content to exchange quality for speed. Some routing architectures route based on the bandwidth of links. Users and organizations benchmark the bandwidth of networking equipment and service providers for purchasing decisions and verifying service level agreements. Researchers measure bandwidth to understand the behavior of the Internet.; However, the diversity of the Internet makes bandwidth measurement challenging. The capacity, utilization, and latency of Internet links vary over several orders of magnitude. In addition, the heterogeneity of administrative domains inhibits the deployment of measurement infrastructure at the network core and end hosts.; The contribution of this dissertation is to increase the accuracy and decrease the overhead of doing end-to-end bandwidth measurement. Our thesis is that it is possible to do accurate and efficient end-to-end bandwidth measurement in the current heterogeneous Internet. We present a variety of techniques to deal with these challenges. Packet Tailgating is a technique to measure all the link bandwidths along a path. It requires no modifications to existing routers and typically requires 50% fewer probe packets than existing techniques, although the estimates of all current end-to-end techniques (including packet tailgating) can deviate from the nominal by as much as 100%. Receiver Only Packet Pair measures the bottleneck bandwidth along a path without requiring measurements from the sending host. Adaptive Kernel Density Estimation Filtering improves the accuracy of bottleneck link measurement by filtering out the effect of cross traffic, even when link bandwidths differ by several orders of magnitude. Potential Bandwidth Filtering improves the accuracy of passive bottleneck link bandwidth measurement by filtering out the effect of applications that send packets at a low rate. The combination of these techniques to measure bottleneck link bandwidth generates estimates that are within 10% of the nominal. |
