Video receiver based real-time estimation of channel capacity

This paper examines the problem of real-time estimation of the capacity, which is also known as the bottleneck bandwidth, of a network path using end-to-end measurements in a video streaming application. We utilize two basic packet-pair bandwidth-sampling methods and show how they can be applied in real-time to the video traffic. We then examine the performance of both sampling methods in a number of tests conducted using an MPEG-4 congestion-controlled streaming application over a Cisco network under a variety of conditions (including high link utilization scenarios). In addition, we study two simple estimation techniques, which can be applied in real-time to the collected samples, and show their performance in the same Cisco network with each of the sampling methods. We focus here on low-complexity and simple estimators that can be used in real-time by a wide range of receivers. We find that the sampling methods combined with the best estimator maintain very accurate estimates for the majority of the corresponding session in a variety of scenarios and could in fact be used by the application for congestion control in video over the Internet.