1. Faculty of Engineering and Information Technology, Software Engineering Department, Taiz University, Taiz, Yemen
2. Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA
3. Lightwave Research Laboratory, School of Engineering and Technology, Sunway University, Petaling Jaya, Malaysia
4. School of Computing, Universiti Utara Malaysia,Malaysia, Sintok, Malaysia
5. InterNetworks Research Laboratory, School of Computing, Universiti Utara Malaysia, Malaysia, Sintok, Malaysia