A mobile ad hoc network (MANET) R. Ramanathan, J. Redi, IEEE Commun Magaz 40(5): 20–22, 2002,  is an autonomous system of mobile routers as well as hosts connected by wireless links which form an arbitrary graph when taken together. The mobile nodes roam around in a given area and organize themselves to form a network via wireless links. The network’s topology changes regularity due to node movement. Such kind of network may operate in a stand-alone fashion or may be connected to the larger network such as the Internet. Ad hoc networks are characteristically different because they do not require any prior fixed infrastructure. Instead, the network nodes relay each other’s packet towards their final destinations via several hosts using their self-created topology. An example of a typical MANET topology is shown in Fig. 3.1.