Adaptive Internet Gateway Discovery Scheme for Mobile Ad Hoc Networks

To integrate mobile ad hoc networks with the fixed Internet, it is important for mobile nodes to obtain the information of available gateways. To achieve this purpose, gateways periodically flood advertisements to all the nodes or nodes send solicitations on demand. These two approaches are so-called the proactive and the reactive gateway discovery. The hybrid gateway discovery combines these two approaches to provide a trade-off between efficiency and overhead by limiting the flooding scope of gateway advertisements and adjusting the advertisement interval. The flooding scope and advertisement interval should be carefully chosen to achieve good performance. This paper proposes a new adaptive hybrid gateway discovery scheme by dynamically adjusting the TTL value of advertisement packets and the advertisement interval according to the topology change and the movement of nodes. Simulation results show that our solution can achieve better performance than others under the circumstance of high traffic loads.