AN EFFICIENT MECHANISM FOR CONNECTIVITY OF INTERNET & MANET

Abstract

Mobile ad hoc networks are extremely flexible, self-configurable and easy-to-deploy wireless networks. These properties make them an attractive component of future mobile and wireless network architectures. With the advent of future wireless networks consisting of an integration of different heterogeneous wireless technologies, the interconnection of MANETs to fixed IP networks is an area, which is becoming of paramount importance. In such scenarios, commonly known as hybrid ad hoc networks, mobile nodes are witnessed as an easily deployable extension to the existing infrastructure. Some nodes act as "gateways" and can be used by other mobile nodes to communicate with the nodes on fixed network. The challenge in interconnecting ad hoc networks to the Internet stems from the need to inform ad hoc nodes about available gateways in an extremely changing scenario while making a minimal consumption of the scarce network resources such as CPU capacity, storage capacity, battery power and bandwidth. Thus, an efficient gateway discovery becomes one of the key elements to enable the use of hybrid ad hoc networks. There are several routing protocols for ad hoc networks (e.g. AODV, DSR), which are used for routing within mobile ad hoc network. These protocols can be extended to provide communication between a mobile node and a node on fixed network (e.g. Internet), or to discover the "gateway". In this dissertation work we have modified AODV routing protocol to provide connectivity between MANETs and Internet. We have also proposed an efficient complete adaptive approach for gateway discovery. We have implemented the solution using Network Simulator 2 (NS 2). The simulation results. show that the proposed complete adaptive discovery mechanism is efficient and has reduced overheads. The parameters used for the performance comparison of our approach with the earlier approaches are packet delivery fraction (pdf) and number of overhead messages.