| This dissertation presents a suite of adaptive and efficient position-based protocols for neighbor discovery, routing, and location service in mobile ad-hoc networks. These protocols use the position information of nodes, which helps them circumvent several problems due to node mobility. In this dissertation, we develop: (1) Three new hello protocols, which use adaptive and on-demand techniques and trade a little accuracy of neighbor tables or the end-to-end delay to reduce the hello message overhead significantly. (2) A localized and high-performance angular-routing protocol (alphaRP), which combines greedy forwarding along with angle-based forwarding heuristics to circumvent dead ends. (3) The Greedy forwarding with Geographic Path-Based Recovery (GGPR) protocol employes a novel dead end recovery mechanism using geographic paths. It incurs a low communication overhead and guarantees packet delivery if the source and the destination are connected. (4) The hierarchical light-weight location service protocol (HLLS) and the on-demand location service (OLS) protocol to track the position of mobile nodes in ad-hoc networks. Both these protocols use (a) a novel concept of a geographic hierarchy, and (b) routing to a position (as opposed to a node) to achieve communication efficiency. Further, they are scalable with respect to the number of nodes, node mobility, and network traffic. (5) A self-healing On-demand Geographic-Path Routing Protocol (GGPR), which establishes geographic paths towards the destination, and forwards packets along these paths. A geographic path decouples node ID's from the path, thus, any node along the geographic path can forward a packet towards its destination. This decoupling reduces path breaks significantly even in mobile networks. An assoicated path-healing mechanism helps geographic paths adapt to the network topology. (6) A robust position-based protocol, OGPR version 2 (OGPRv2), which copes with both unidirectional links and selfish nodes.; All these protocols adapt to dynamically changing network topologies, deliver high performance, and require low control overhead compared to their well-known counterparts. The dissertation shows the practicality of each of these protocols under various networking scenarios through performance results obtained via extensive simulation studies, and analytically where possible.; Keywords. Position-based protocols, neighbor discovery, routing, location service, ad-hoc networks. |
