Performance Investigation of Simulation Models of Wireless Mobile Ad Hoc Networks

ABSTRACT: Wireless ad hoc networks have attracted great interest in last few years, due to envisioning of their great potential in military and commercial applications. Being a wireless network of mobile computing devices that doesn’t rely on any pre-established infrastructure, they eliminate the complexity of infrastructure setup. Accordingly become popular in several application areas, such as battlefields, emergency areas, wireless sensor networks and hybrid wireless networks and can be deployed anywhere at anytime. This thesis provides a Petri-net-based model of a wireless ad hoc network, where all fundamental aspects with the proposed, a general and more realistic, inter-node communication scheme are implemented. The model is implemented in terms of extended Petri nets and the simulation system Winsim is used in development and simulation. There are two types of modules in the model, namely node and switching module, that is, the model is organized in a multi-module system. Three fundamental performance metrics of an ad hoc network – packet delivery ratio, average number of hops and relative network traffic – were investigated under different transmission radius, model parameters and conditions of mobility model and inter-node communication scheme. The entire model, together with the proposed inter-node communication scheme can be used for study of routing protocols as well as other aspects of information transmission in wireless ad hoc networks. The further study of this thesis can be the development of an efficient routing protocol that results in reduced network load and energy usage at mobile nodes as well as increasing the security of the network. The thesis is organized as follows. Chapter 1 introduces the era of computer and wireless networks, with the problem and statement of the work goal of the thesis. Chapter 2 provides a survey of the existing methods and tools for modeling and simulation of wireless ad hoc networks. Chapter 3 is devoted to the specification of system assumptions and the chosen mobility model. Chapter 4 explains the proposed scheme of inter-node communication. In Chapter 5, the organization and components of the entire model is considered. Chapter 6 describes the simulation setup and results of simulation. Chapter 7 concludes the thesis. Keywords: Mobile wireless ad hoc networks, oriented links, simulation, extended Petri nets, mobility models.