Ad Hoc Networks: Routing, Qos and Optimization

Chapter 1

Introduction to Ad Hoc Networks

 

 

 

1.1. Introduction

With recent technological advances in the domain of wireless communications and the emergence of portable computing devices, researchers have turned their attention to improving the function of networks and, in particular, to ensuring rapid access to information independent of time or place.

Until very recently, wireless networks were based exclusively upon planned and sized infrastructures and a hierarchical control of operations. With the vast expansion of wireless applications, particularly personal and local networks, the need for self-organization, independence, adaptability, and cost reduction has become apparent. Mobile ad hoc networks (MANETs) provide a solution that effectively responds to these issues.

The concept of MANETs attempts to expand notions of mobility to all parts of the environment. Unlike networks based on cellular communication, no central administration is available; mobile operators themselves provide a network infrastructure on an ad hoc basis. No supposition or limitation is made regarding the size of the ad hoc network, which can contain hundreds, or even thousands, of cellular units.

In this chapter, we present the evolution from networks with fixed infrastructures to MANET networks. Next, we list the different characteristics of ad hoc networks and give a few examples of their application.

1.2. Wireless networks and communications

In the past few decades, technological advancements ...