Affiliation: | [1]School of Computer Science, Beijing University of Posts and Telecommunications, Beijing 100876, P. R. China; [2]School of Software Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, P. R. China; [3]Key Laboratory of Trustworthy Distributed Computing and Service (BUPT), Ministry of Education, Beijing 100876, P. R. China; [4]Department of Electrical Engineering, University of Hawaii, Honolulu, Hawaii, U.S. |