Abstract:

Security strength and network performance are the two sides of a coin. If, one of these is enhanced, the other will suffer. Achieving a good trade-off between these two extremes is a fundamental challenge in security design for mobile ad-hoc networks which are basically self-organised wireless interconnecting communication devices that would either extend (or) operate in concert with the wired networking infrastructure.

Lot of research is going on in this field in respect of the unique characteristics of ad-hoc networks such as open peer-to-peer network architecture, shared wireless medium, highly dynamic topology and stringent resource constraints. These limitations make a strong case for building multi-fence security solutions that meet both the goals of security as well as desirable network performance. Ad-hoc networks can be established on demand and disappear when there is no need, traditional security solutions applicable to wired-networks will not be sufficient because of the inherent limitations of such networks. In such an open and distributed communication environment, a central authorisation facility that makes more stringent security will not be available. Self organisation in ad-hoc networks aims to bring orderliness to the evolving distributed systems with the least possible human intervention. The three important characteristics of such a self organised systems are - I.P (Internet Protocol) auto-configuration, peer-to-peer networking, and shared open-content web pages.
The fundamental security problem in mobile ad-hoc network is: the protection of its basic functionality to deliver the "data bits" from one node to the other. Unlike wired networks that have dedicated routers, each mobile node in an ad-hoc network will function as a router and forward packets to other peer nodes. Two basic approaches to protect mobile ad-hoc networks are: proactive and reactive.

In this paper, an attempt is made to discuss certain fundamental security design challenges like denial-of-service attacks, providing link-layer security support, protecting routing and forward protocal, secured authentication and end-to-end communication through data encryption, preventing viruses, worms and application abuses, at different layers in a wireless ad-hoc network.

Keywords:

Mobile Ad-hoc Networks, Q.O.S. (quality of service), Security Solutions, Net Wohk Layers, Link-layer, Viruses, Worms, Nodes.