Hybrid routing and bridging strategies for large scale mobile ad hoc networks

Multi-hop packet radio networks (or mobile ad-hoc networks) are an ideal technology to establish "instant" communication infrastructure for military and civilian applications in which both hosts and routers are mobile. In this dissertation, a position-based/link-state hybrid, proactive routing protocol (Position-guided Sliding-window Routing---PSR) that provides for a flat, mobile ad-hoc routing architecture is described, analyzed and evaluated. PSR is based on the superposition of link-state and position-based routing, and it employs a simplified way of localizing routing overhead, without having to resort to complex, multiple-tier routing organization schemes. A set of geographic routing zones is defined for each node, where the purpose of the ith routing zone is to restrict propagation of position updates, advertising position differentials equal to the radius of the (i-1)th routing zone. Thus, the proposed protocol controls position-update overhead generation and propagation by making the overhead generation rate and propagation distance directly proportional to the amount of change in a node's geographic position. An analytical model and framework is provided, in order to study the various design issues and trade-offs of PSR routing mechanism, discuss their impact on the protocol's operation and effectiveness, and identify optimal values for critical design parameters, under different mobility scenarios. In addition an in-depth performance evaluation, via modeling and simulation, was performed in order to demonstrate PSR's operational effectiveness in terms of scalability, mobility support, and efficiency. Furthermore, power and energy metrics, such as path fading and battery capacity considerations, are integrated into the routing decision (cost function) in order to improve PSR's power efficiency and network lifetime. It is demonstrated that the proposed routing protocol is ideal for deployment and implementation especially in large scale mobile ad hoc networks.;Wireless local area networks (WLAN) are being deployed widely to support networking needs of both consumer and enterprise applications, and IEEE 802.11 specification is becoming the de facto standard for deploying WLAN. However IEEE 802.11 specifications allow only one hop communication between nodes. A layer-2 bridging solution is proposed in this dissertation, to increase the range of 802.11 base stations using ad hoc networking, and therefore solve the hotspot communication problem, where a large number of mobile users require Internet access through an access point. (Abstract shortened by UMI.).