Interconnecting MANET And INTERNET--Design And Implementation Of Ad-Hoc Dynamic Gateway Based On Mobile IP

MANET (Mobile Ad Hoc Networks) is a temporary autonomous network which consists of many router-enabled mobile nodes with radio transceiver devices. And it does not have a wired infrastructure to support mobile networks.As the development of real-time multimedia services over Internet, it prompts people to consider the connectivitis between MANET and infrastructure networks especially Internet to expand the fixed network and the wireless applications. Therefore, the research of connectivities between MANET and Internet has profound significance and practical value. Currently, the main stream research method is that appoint one fixed node as a selected gateway.Mobile IP is a global mobile features available on the Internet program, it has scalability, reliability and security, and the communication maintains when mobile node switch among different links.This project comes from the Ministry of Education personnel abroad, which aims to develop a combination of MANET routing protocols and mobile IP, dynamic gateway solution, in order to achieve a dynamic MANET connected to the Internet. The issue of concern is based on the dynamics of mobile IP gateway solution.The paper first discusses the mobile IP working principle, the key technologies and their implementations, and then focuses on the dynamics of the gateway based on mobile IP architecture, including the gateway discovery mechanism, gateway switching mechanism, and describes the Ad Hoc relevant protocol, such as AODV, OLSR and so on.According to requirements, we design the final application, the module design ideas, as well as mobile IP module and the Ad hoc Protocol Module process communication mechanism. And we propose a dynamic gateway algorithm to achieve the gateway discovery and gateway handoff. At the end of this paper, we also discribe the test scenarios and NS2 simulation, the test results show that our scheme has achieve the goal without increasing the network overhead.Finally, the paper points out the shortcomings of the study and future research directions.