Quality of Service (QoS) Provisioning in Mobile Ad-Hoc Networks (MANETs)
Masoumeh Karimi · InTech eBooks · 2011
Next generation of wireless communication systems are engineered to service independent mobile users. These autonomous mobile users (nodes) are connected through wireless links to build a live and on-the-fly network called a Mobile Ad-hoc Network (MANET). The nodes involved in this system should collaborate among themselves and can function as both hosts and routers. They work together only based on the mutual agreement, without knowing about the network topology around them. Hence, maintaining appropriate Quality of Service (QoS) for MANETs is a complex task due to the dynamic behavior of the network topology. Commonly, QoS for a network is measured in terms of the guaranteed amount of data which a network transfers from one place to another during a certain time. The QoS is identified as a set of measurable pre-specified service requirements; such as delay, bandwidth, probability of packet loss, and delay variance (gitter). Therefore, a network needs to meet such requirements for the end users to satisfy a particular application while transporting a packet stream from a source to its destination. The traffic types in ad-hoc networks are quite different from other infrastructures and the widespread use of wireless technologies in MANETs make the QoS approaches more complicated. The application of MANETs was first proposed for military battlefield and disaster recovery. MANETs are mainly used when we require a quick deployment of a cooperative and distributed computing network, such as wireless sensor networks and integrated cellular networks. Accordingly, such networks are demanding to have special features; i.g., autonomous architecture, distributed operation, multi-hop routing, reconfigurable topology, fluctuating link capacity, and light weight terminals. Thus, several interesting issues can be technically involved when designing MANETs; such as security, routing, reliability, internetworking, and power consumption due to the shared nature of the wireless medium, node mobility, and battery limitations. Therefore, providing suitable QoS for delivery of real-time communications in MANETs is more challenging than the ones in the fixed networks. This chapter attempts to provide the reader with a basic understanding of the needs and techniques utilized for the MANETs in today’s telecommunication networks by emphasizing on the scalability issues, routing protocols, security administrations, and energy management strategies. Also, a special attention is paid on the fundamental problems that will occur when trying to provide the QoS. The structure of this chapter is