Mobile ad hoc network is a self-configuring, self-organizing and decentralized network. It is connected by wireless links. Each device in a MANET is free to move independently in any direction. Hence it can change its links to other devices frequently. It is a collection of mobile wireless nodes that can dynamically form a network without using any pre-existing infrastructure. Due to characteristics like temporary topology and absence of centralized authority, routing is one of the major issues in ad hoc networks. Because of connectivity richness in mobile ad hoc networks, there often exist multiple paths between a source and a destination.