Performance Evaluation of Different Hybrid Gateway Discovery Methods

Mobile Ad hoc Network (MANET) consists of a set of wireless nodes which are connected but can freely move. These mobile nodes include a particular type of nodes, known as ‘gateway’ nodes, which are directly connected with internet and other mobile nodes in a MANET get internet access through them. Prior to access, any mobile node requires discovering such a nearest gateway node using a gateway discovery method. Both proactive and reactive methods suffer from higher delay and poor packet delivery. Hybrid method addresses these issues where the gateway node proactively broadcasts gateway advertisement message to mobile nodes up-to a particular number of hops. Beyond that, the other mobile nodes send gateway discovery messages to gateway nodes so that the gateway nodes can reactively reply. Prior works on hybrid methods use static values as number of hops. In a state-of-the-art work, an adaptive hybrid method was proposed where values for number of hops were dynamic. This paper discusses the performance of this adaptive hybrid method with other hybrid methods which are based on static number of hops. Results show that the adaptive method outperforms other static hybrid methods. Keywords- Adaptive hybrid method, Hybrid method with variable hop counts, Advertisement interval, TTL value, Hop count. 1