Highly Dynamic Nature of Mobile AD-HOC Networks (MANETs): Requirement of Stringent Security Measures

Wireless mobile AD-HOC networks (MANETs) can be established on demand and disappear when there is no need. Each mobile node in the network acts both as a terminal and also as a router. Thus, each mobile node is having a capability of forwarding packets of information to other peer nodes. The nodes are, basically, self-organized wireless interconnecting communication devices which can either extend or operate in concert with the wired networking infrastructure. Lot of research is going on, in this field, regarding the unique characteristics of AD-HOC networks such as open peer-to-peer network architecture, highly dynamic topology, shared wireless medium, stringent resource control etc. These limitations make a strong case for a desirable network performance with reasonably good security measures for the information interchange. Unlike networks that have dedicated routers, the nodes in the MANETs are highly dynamic in nature, there by liable for easy security breaches. Security Strength and network performance (Q.O.S) 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 challenging task in security design for mobile AD-HOC networks since these networks are characterized by an open and distributed communication environment where there is no central authorization facility that ensures more stringent security. An attempt is made in this paper to discuss certain topologies and security problems like (i) Denial-of-service attacks, (ii) Secured authentication, (iii) Protecting routing and forwarding of packets, (iv) End-to-end Communication through data encryption, (v) Preventing viruses, worms and application abuses at different layers.