Exploiting the Path Propagation Time Differences in Multipath Transmission with FEC
IEEE Journal on Selected Areas in Communications
We consider a transmission of a delay-sensitive data stream (e.g., a video call) from a single source to a single destination. The reliability of this transmission may suffer from bursty packet losses -the predominant type of failures in today's Internet. An effective and well studied solution to this problem is to protect the data by a Forward Error Correction (FEC) code and send the FEC packets over multiple paths. In this paper, we show that the loss rate of such a classic multipath FEC
... multipath FEC scheme can often be significantly reduced, while keeping the total transmission rate and delay unchanged. Our key observation is that the propagation times on the available paths often significantly differ, usually by 10-100ms. We propose to exploit these differences by appropriate packet scheduling that we call 'Spread'. We evaluate our solution with a precise, analytical formulation and trace-driven simulations. Our studies show that Spread substantially outperforms the state-of-the-art solutions. It typically achieves two-to five-fold improvement (reduction) in the effective loss rate. Or conversely, keeping the same level of effective loss rate, Spread significantly decreases the observed delays and helps fighting the delay jitter. Index Terms-Multipath transition, FEC, block delay, propagation time, loss rate, total transmission rate, scheduling Maciej Kurant received a M.Sc. degree from Gdansk University of Technology, Poland, in 2002, and a Ph.D. degree from EPFL, Lausanne, Switzerland, in 2009. Currently, he is a postdoc at University of California, Irvine. His main areas of research interest include sampling and inference from large-scale networks (such as Internet topologies or the human brain), multipath routing with FEC, and survivability in WDM networks. He is also a founder of AcronymCreator.neta tool that helps creating new, meaningful acronyms.