1 Introduction
In cellular networks, a mobile host (MH) is allowed to communicate with another MH anytime from anywhere with the help of the mobile service station (MSS [1]). The geographical area covered by a cellular network is divided into smaller regions called cells [2]. In each cell, there is one MSS which serves the MHs present in the cell. An MH communicates with the MSS in its cell directly through a wireless link, while MSSs are usually connected by a wired network. Such an architecture [3] is shown in Fig. 1. A model of a wireless communication network.