The popularity of wireless communications systems can be seen almost everywhere in the form of cellular networks, WLANs and WPANS. In addition, small portable devices have been fully equipped with various communication interfaces building a heterogeneous environment in terms of access technologies. the future heterogeneous environments are expected to integrate wireless technologies such as WLANs, WMANs and WWANs, based on the individual network architectures. It is envisioned that the next generation wireless systems would provide convergence of various wireless network technologies so as to have architectures with global connectivity [27, 28]. We present a view of the various routing protocols present in the Mobile AdHoc Networks (MANETs) and compare them as to see the best performance oriented. The Integration of different access technologies is a very complex task and involves issues at all layers of the protocol stack.

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