Liu Hongquan, Ph.D. candidate in the Department of Electronic Engineering of Tsinghua University. His current research interests include wireless mesh networks and protocols, network coding congestion control. Email: liuhq.thu@gnail.com Gu Yuantao, associate professor and doctoral su- pervisor with the Department of Electronic Engi- neering, Tsinghua University. His current re- search interests include wireless networking, sig- nal processing and image processing. The corre-sponding author. Email: gyt@tsinghua.edu.cn