Integration of Wireless Mobile Ad Hoc Networks and the Internet : Heterogeneous Networks: An Integrated Internet- MANET (IIM)

Wireless Mobile Ad Hoc Network (MANET), an infrastructure-less, autonomous, standalone and self organizing network is one of the wireless technologies gaining popularity. It can be deployed in almost any environment with ease and flexibility. But it is constrained by limited wireless coverage and limited connectivity. The integration of MANET routing protocols with IP protocol makes Internet connectivity to the MANET nodes a plausible task. Due to the different architectural mismatches between the Internet and MANETs with regard to their communication topology, routing protocols, and operation, it becomes necessary to introduce an intermediate entity known as Gateway, capable of connecting to the Internet using mobile IP and to MANET using an ad hoc routing protocol. Mobile IP agents or access points are placed at the edge of the Internet to aid the MANET nodes realize multi-hop wireless Internet access. The important issues for providing Internet connectivity for ad hoc networks includes reduction of the mobile IP overhead,routing protocol overhead, improving the packet delivery ratio, gateway connectivity ratio and reducing the end-end delay & providing global connectivity.