Multipath Cross-Layer Service Discovery (MCSD) for Mobile Ad Hoc Networks

In this paper, we propose and study how to provide multipath cross-layer service discovery (MCSD) for mobile ad hoc networks (MANETs). Cross-layer service discovery integrates service discovery into route discovery by taking advantage of network-layer topology information and routing message exchange. Multipath service discovery differs from multipath routing in that multipath service discovery can be either multipath from a client to a server or multipath from a client to multiple servers, depending on the policy used in service selection and invocation. Compared with the traditional unipath cross-layer service discovery (UCSD), MCSD performs better in terms of improving throughput, enhancing service availability and optimizing network-layer resources. However, as a new service discovery scheme, MCSD posts a lot of challenges, particularly in the process of service discovery and how to find the optimal multipath. Due to the complexity of the problem, we focus on double-path cross-layer service discovery (DCSD), a special and most important case of MCSD. We present a heuristic, called iDCSD, which can intelligently find the optimal routes out of the candidate paths from a client to a server and from a client to two servers by minimizing hop count in network layer. Extensive simulation results show that compared with UCSD, i) MCSD delivers better service availability; and ii) the proposed iDCSD leads to a better network-layer performance with reasonable computational complexity.