1. Network and Data Security Key Laboratory of Sichuan Province, University of Electronic Science and Technology of China, Chengdu, China
2. Department of Computer Science, University of Windsor, Windsor, Canada
3. Department of Electrical and Computer Engineering, University of Windsor, Windsor, Canada
4. State Key Laboratory of Integrated Service Networks, Xidian University, Xi’an, China
5. Department of Information Systems and Cyber Security, The University of Texas at San Antonio, San Antonio, TX, USA