Spatial Multipath Location Aided Routing

Mobile ad-hoc networks (MANETs) are infrastructure-free networks of mobile nodes that communicate with each other wirelessly. There are several routing schemes that have been proposed and several of these have been already extensively simulated or implemented as well. The primary applications of such networks have been in disaster relief operations, military use, conferencing and environment sensing. There are several ad hoc routing algorithms at present that utilize position information (usually in two dimensional terms) to make routing decisions at each node. Our goal is to utilize three-dimensional (3D) position information to provide more reliable as well as efficient routing for certain applications. We thus describe extensions to various location aware routing algorithms to work in 3D. We propose a new hierarchical, zone-based 3D routing algorithm, based on GRID by Liao, Tseng and Sheu. Our new algorithm called "Hyper-GRID" is a hybrid algorithm that uses multipath routing (alternate path caching) in 3D. We propose replacing LAR with Multipath LAR (MLAR) in GRID. We have implemented MLAR and are validating MLAR through simulation using ns-2 and studying its efficiency, scalability and other properties. We use a random waypoint mobility model and compare our MLAR approach versus LAR, AODV and AOMDV in both 2D and 3D for a range of traffic and mobility scenarios. Our simulation results demonstrate the performance benefits of MLAR over LAR and AODV in most mobility situations. AOMDV delivers more packets than MLAR consistently, but does so at the cost of more frequent flooding of control packets and thus higher bandwidth usage than MLAR.