A Geometric Approach to Server Selection for Interactive Video Streaming

摘要

Many distributed interactive multimedia applications, such as live video conferencing and video sharing, require each participating client to transmit its captured video stream to other clients via relay servers. We consider connecting multiple clients through multiple relay servers and study the server selection problem from a dense pool of content delivery network edge locations and datacenters to reduce the end-to-end delays between clients. To achieve scalability in the presence of a large number of candidate servers, we formulate server selection as a geometric problem in a delay space instead of in a graph, which turns out to be an extension of the well-known Euclidean -median problem. We propose practical approximation schemes when using only one or two servers with theoretical worst-case guarantees as well as fast heuristics when using servers. We demonstrate the benefit of our optimized multiserver selection schemes through extensive evaluation based on real-world traces collected from the PlanetLab and Seattle platforms, containing personal mobile devices as well as real network experiments based on a prototype implementation.