Mobile Ad-Hoc Networks

Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of-the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: quality-of-service and video communication, routing protocol and cross-layer design. A few interesting problems about security and delay-tolerant networks are also discussed. This book is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks

Efficient Cross Layer Designs for IEEE 802.11 Wireless Networks

Various properties of wireless networks, such as mobility, frequent disconnections and varying channel conditions, have made it a challenging task to design networking protocols for wireless communications. In this dissertation, we address several problems related to both the routing layer and medium access control (MAC) layer in wireless networks aiming to enhance the network performance. First, we study the effect of the channel noise on the network performance. We present mechanisms to compute energy-efficient paths in noisy environments for ad hoc networks by exploiting the IEEE 802.11 fragmentation mechanism. These mechanisms enhance the network performance up to orders of magnitude in terms of energy and throughput. We also enhance the IEEE 802.11 infrastructure networks with a capability to differentiate between different types of unsuccessful transmissions to enhance the network performance. Second, we study the effects of the physical layer capture phenomena on network performance. We modify the IEEE 802.11 protocol in a way to increase the concurrent transmissions by exploiting the capture phenomena. We analytically study the potential performance enhancement of our mechanism over the original IEEE 802.11. The analysis shows that up to 35% of the IEEE 802.11 blocking decisions are unnecessary. The results are verified by simulation in which we show that our enhanced mechanism can achieve up to 22% more throughput. Finally, we exploit the spatial reuse of the directional antenna in the IEEE 802.11 standards by developing two novel opportunistic enhancement mechanisms. The first mechanism augments the IEEE 802.11 protocol with additional information that gives a node the flexibility to transmit data while other transmissions are in its vicinity. The second mechanism changes the access routines of the IEEE 802.11 data queue. We show analytically how the IEEE 802.11 protocol using directional antenna is conservative in terms of assessing channel availability, with as much as 60% of unnecessary blocking assessments and up to 90% when we alter the accessing mechanism of the data queue. By simulation, we show an improvement in network throughput of 40% in the case of applying the first mechanism, and up to 60% in the case of applying the second mechanism

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Cooperative & cost-effective network selection: a novel approach to support location-dependent & context-aware service migration in VANETs

Vehicular networking has gained considerable interest within the research community and industry. This class of mobile ad hoc network expects to play a vital role in the design and deployment of intelligent transportation systems. The research community expects to launch several innovative applications over Vehicular Ad hoc Networks (VANETs). The automotive industry is supporting the notion of pervasive connectivity by agreeing to equip vehicles with devices required for vehicular ad hoc networking. Equipped with these devices, mobile nodes in VANETs are capable of hosting many types of applications as services for other nodes in the network. These applications or services are classified as safety-critical (failure or unavailability of which may lead to a life threat) and non-safety-critical (failure of which do not lead to a life threat). Safety-critical and non-safety-critical applications need to be supported concurrently within VANETs. This research covers non-safety-critical applications since the research community has overlooked this class of applications. More specifically, this research focuses on VANETs services that are location-dependent. Due to high speed mobility, VANETs are prone to intermittent network connectivity. It is therefore envisioned that location-dependence and intermittent network connectivity are the two major challenges for VANETs to host and operate non-safety-critical VANETs services. The challenges are further exacerbated when the area where the services are to be deployed is unplanned i.e. lacks communication infrastructure and planning. Unplanned areas show irregular vehicular traffic on the road. Either network traffic flows produced by irregular vehicular traffic may lead to VANETs communication channel congestion, or it may leave the communication channel under-utilized. In both cases, this leads to communication bottlenecks within VANETs. This dissertation investigates the shortcomings of location-dependence, intermittent network connectivity and irregular network traffic flows and addresses them by exploiting location-dependent service migration over an integrated network in an efficient and cost-effective manner

Enhanced QoS for real-time multimedia delivery over the wireless link using RFID technology.

This thesis presents a Sensor Guided Wireless Adaptation Scheme (SGWAS) that works in a micromobility domain. SGWAS infers the reason of high packet loss in a realtime multimedia flow received by a mobile node in a wireless cell. Determining the reason of packet loss relies on information obtained from wireless sensors, specifically RFID devices scattered in the cell, to detect the location of the mobile node. If packet loss is due to wireless link congestion, then local rate adaptation is applied in the cell. However, if it is due to handoff or signal propagation effects, e.g. obstruction or attenuation, then rate adaptation is not performed. The source adapts its transmission rate if congestion occurs in the wired network. SGWAS helps improve the quality of service and avoids unnecessary rate adaptation. Simulation results demonstrate that SGWAS identifies the reason of high packet loss and performs rate adaptation only when needed.Dept. of Computer Science. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2006 .E58. Source: Masters Abstracts International, Volume: 45-01, page: 0352. Thesis (M.Sc.)--University of Windsor (Canada), 2006