Effective layer-3 protocols for integrating mobile ad hoc network and the Internet

Abstract

The next generation mobile communication systems will be based on infrastructure wired/ wireless LAN technologies and ad hoc networks. Such hybrid networks benefit the extension of infrastructure network coverage using ad hoc connectivity apart from offering the ad hoc nodes access to the resources of the wired/infrastructure networks. In most of the integration strategies Mobile IP is integrated with the ad hoc network routing protocol to provide Internet access and in few of the strategies the routing protocol has been enhanced to provide the connectivity without using Mobile IP.Few strategies use fixed gateways, others use mobile gateways. In this paper, we proposed two different approaches of integrating ad hoc network and the wired network using two different protocols. In the first part of this paper, an extended DSDV protocol, named as Efficient DSDV (Eff-DSDV) protocol is used to provide bi-directional connectivity between exclusive ad hoc hosts and the hosts on the Internet (wired network). The proposed framework uses one of the ad hoc hosts known as Mobile Gateway Node (MGN) to act as a bridge between ad hoc network and the Internet. The performance comparison is made between the proposed approach and one of the leading strategies based on packet delivery ratio, end-end delay, and control overhead. The experimental results indicate that the performance of the proposed strategy is better than the existing strategies. Later in the paper, we propose a framework for integrating mobile ad hoc network and the Internet using both fixed and mobile gateways. The ad hoc hosts can access the Internet using either fixed or mobile gateway, based on criteria of distance, load on the gateway. An extended version of AODV routing protocol is used in the framework. The objective behind using both fixed and mobile gateways is to increase the reliability of the Internet access, scalability, providing transparent Internet access to the ad hoc hosts and in general improve the performance of the integrated framework. The proposed framework is a hybrid architecture involving two-layer and three-layer approaches of integration. The performance comparison of the two proposed strategies has been done under common metrics. © 2009 Springer.