A hybrid gateway discovery method for mobile ad hoc networks

Mobile Ad hoc Network (MANET) consists of a set of mobile nodes which communicate among them only using their wireless interface. In order to get connected with internet, mobile nodes need to find out Gateway (GW), a particular type of mobile nodes which are directly connected with internet. Proactive, reactive, and hybrid, are the three methods for gateway discovery. In hybrid approach, GW nodes maintain their proactive property only within a range of the MANET and GW nodes do not broadcast advertise message outside that range. Current hybrid approach uses a very small heuristic value for this range and therefore majority portion of the MANET still has to follow reactive approach. This paper proposes a novel hybrid method using an adaptive value for this range which ensures proper utilization of hybrid method. In this method, after receiving replies from several mobile nodes in response to initial advertisement message, the GW sets its range for next broadcast based on the mean distance of all mobile nodes those have replied. This variable range allows the GW to send advertise message to long distance and at the same time follows reactive property too. Experiments show that this proposed approach achieves better results in term of packet delivery rate, delay, and packet drop.