Huang Hongyu, received the B.S. and M.S. degrees in computer science from Chongqing Normal University and Chongqing University, in 2002 and 2005, respectively. He is currently working toward the Ph. D. degree with the Department of Computer Science and Engineering, Shanghai Jiaotong University, Shanghai, China. His research interests include wireless networks and intelligent transportation systems.To whom correspondence should be addressed. E-mail : hyu _ huang@ es. sjtu. edu. cn