I. Introduction
In recent years, there has been an increasing interest in the Internet Protocol based Wireless Sensor Network (IP-WSN) [1]–[3]. IP-WSN has been applied in various reliable and realtime applications since it emerged. This is due to the integration of IP in WSN not only allowed large-scale deployment but also solved many far distance remote control and monitoring problems which has promised emergency message delivery on time regardless of client location. One of the attractive features of IP-WSN is their mobility support.