Novel AODV based service discovery protocol for MANETS

Service discovery is an inevitable process in most of the network. Mobile AdHoc network (MANET) being self-sustained and resource constrained, sharing of resources and service discovery is very essential. A service discovery protocol designed for a fixed network is not suitable for AdHoc network because of the constraint in the resources, mobility of nodes and the lack of centralized infrastructure. Therefore there arises a need to design protocols specific to MANET. A protocol designed for service discovery at the application layer in Mobile AdHoc Network would generate the same amount of control messages during service discovery as would a routing protocol during route discovery. To ease the network congestion it would be beneficial to integrate service discovery with route discovery. This would discover the services and route simultaneously. Therefore the AdHoc On-demand Distance Vector (AODV) routing protocol being a reactive routing protocol was modified to include service discovery so that as the services are discovered, a route to the service provider is also available. During service discovery if multiple servers are offering the same service, there arises a need to select the best one. We propose a ranking mechanism that selects an optimal server by considering the route and server specific metrics. We also propose an algorithm that performs service discovery by taking care of Expanding Ring Search of AODV protocol so as to be able to discover multiple servers. The proposed approach has been evaluated, and it was observed that the storage overhead is reduced by 50%, average Service Discovery Latency was reduced and the Service Discovery Ratio was improved by 16%.