Exploring Embedded Path Capacity Estimation in TCP Receiver

Accurate estimation of network characteristics, such as capacity, based on non-intrusive measurements is a fundamental desire of several applications. For instance, P2P applications that build overlay networks can use path capacity for optimizing network performance. We present a simple technique to estimate end-to-end Internet paths capacity simply by making adequate inferences at the TCP receiver behavior. Our proposed method does not require access or permission at remote machines. An off-the-shelf Linux kernel is used to implement the method and provide precise measurements. In addition, a large number of experiments in a high speed environment are used to i) validate, ii) show the accuracy and iii) evaluate path capacity heterogeneity of some Internet paths. Applications of our method include improving TCP throughput using the receiver advertised window, and identifying the location of the narrow link (i.e. bottleneck) on an Internet path.