Master Thesis - 2007

Recently, MANET, which allows mobile terminals to create a network autonomously is spotlighted. Terminals can compose a MANET in an easy way without supports from existing infrastructures. Serveral routing protocols for MANET has been developed to deal with frequent topology changes derived from move, entry or quit of terminals. Especially, AODV is receiving much attention because of its flexibility. However, MANET has two major problems such as the low scalability problem and the geographical dependence problem, which are caused by using multihop wireless communications.

To resolve these problems, several methods have been proposed such as extended MAC and/or PHY layer protocols and extended IP layer protocols. Although these methods overcome each problem individually, it is difficult to resolve both of them without detracting the flexibility of MANET.

In this paper, I propose a new method, which uses a dynamic linkage with the IPbased infrastructure to compose a wide area MANET. The proposed method extends AODV and enables to search for destinations on the IP-based infrastructure. Hence, the proposed method settles the low scalability problem by creating shortcut paths on the IP infrastructure. In addition, to overcome the geographical dependence problem, the proposed method connects terminals which are out of radio range each other by using the IP infrastructure. In this way, the proposed method can flexibly establish a wide area MANET, which is scalable and free from geographical constraint.

Finally, simulation experiments show that the proposed method can resolve the low scalability problem and the geographical problem.