Shared Bottleneck Detection Based on Congestion Interval Variance Measurement

The key technical issue of bottleneck fairness-based multipath congestion control is to detect whether two flows share a common bottleneck or not. Previous approaches perform poorly when the delay of the two paths from the shared bottleneck to the common receiver differs significantly (named the path lag problem). In this letter, we propose and implement a shared bottleneck detection scheme based on congestion interval variance measurement (SBDV). Our scheme uses only one-way delay measurement within each flow to detect whether two flows share a bottleneck or not. If the variance of time interval between the two flows experiencing congestion is smaller than a threshold, which is determined by the duration of congestion, the two flows can be considered to share a common bottleneck. Otherwise, they are considered to have different bottlenecks. Our simulation shows that the accuracy of SBDV is high in most of the experiments, even when the bottlenecks are partially overlapped, and our scheme is robust to the troublesome Path lag problem, as compared to other state-of-the-art techniques.