A Hybrid Internet Gateway Discovery Scheme in Mobile Ad Hoc Networks

Although an autonomous mobile ad hoc network (MANET) is useful in many scenarios, work on the integration of MANET with Internet is more desirable. In order to realize such integration, Internet gateway is required. The main issue involved in this case is when and how a mobile node obtains information about available Internet gateways while making a minimal consumption of the scarce network resources. So an efficient gateway discovery for MANET becomes a key element to enable the use of hybrid ad hoc networks in future mobile and wireless networks. Note that performance of the Internet connectivity will be degraded greatly if obvious unidirectional links are ignored and gateway discovery packets are rebroadcast blindly during MANET nodes discovery available Internet gateway, in this paper, an effective hybrid gateway discovery algorithm for MANET is proposed to remove unidirectional links and enhance Internet connectivity simultaneously. The routing protocol called ad hoc on-demand distance vector (AODV) has been modified to set up multihop paths to the Internet gateways in the MANET. Simulation results with NS2 show that this approach can provide better performance to avoid unidirectional links and can achieve good connectivity while keeping overhead costs low.