Download or read book Channel Sharing of Competing Flows in Ad Hoc Networks written by and published by . This book was released on 2003 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper studies the fairness with which competing flows share the channel in ad hoc networks using collision avoidance protocols. It is shown that the required multihop coordination makes the backoff-based distributed fair queueing schemes less effective. Using extensive simulations of two competing flows with different underlying network configurations, it is shown that the commonly used flow contention graph is insufficient to model the contention among nodes and that various degrees of unfairness can take place. The fairness problem is more severe in Transmission Control Protocol (TCP)-based flows due to the required acknowledgment traffic, and TCP throughput also is negatively affected. A measurement-based fair scheme is analyzed in which nodes estimate their fair share of the channel from overheard traffic and adjust their backoff window accordingly (voluntarily). It is shown that such a scheme achieves much better fairness but sacrifices too much throughput. These results indicate that more explicit information exchange among contending nodes is mandatory to solve the fairness problem conclusively while maintaining reasonable throughput.
Download or read book New Topics in Theoretical Computer Science written by Oleg N. Terikhovsky and published by Nova Publishers. This book was released on 2008 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical computer science focuses on the more abstract, logical and mathematical aspects of computing, such as the theory of computation, analysis of algorithms and semantics of programming languages. This new book presents the latest research in the field from around the globe.
Download or read book Eighth IEEE International Symposium on Computers and Communication written by and published by . This book was released on 2003 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AD HOC NETWORKS written by Prasant Mohapatra and published by Springer Science & Business Media. This book was released on 2006-01-16 with total page 287 pages. Available in PDF, EPUB and Kindle. Book excerpt: AD HOC NETWORKS: Technologies and Protocols is a concise in-depth treatment of various constituent components of ad hoc network protocols. It reviews issues related to medium access control, scalable routing, group communications, use of directional/smart antennas, network security, and power management among other topics. The authors examine various technologies that may aid ad hoc networking including the presence of an ability to tune transmission power levels or the deployment of sophisticated smart antennae. Contributors to this volume include experts that have been active in ad hoc network research and have published in the premier conferences and journals in this subject area. AD HOC NETWORKS: Protocols and Technologies will be immensely useful as a reference work to engineers and researchers as well as to advanced level students in the areas of wireless networks, and computer networks.
Download or read book Quality of Service IWQoS 2003 written by Kevin Jeffay and published by Springer. This book was released on 2003-08-03 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: The refereed proceedings of the 10th International Workshop on Quality of Service, IWQoS 2003, held in Berkeley, CA, USA, in June 2003. The 27 revised full papers presented were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on analysis and modeling, resource allocation and admission control, multimedia and incentives, dependability and fault tolerance, routing, availability and dependability, Web services, rate-based QoS, and storage.
Download or read book Optical Electronic Materials and Applications written by Yu Hang Yang and published by Trans Tech Publications Ltd. This book was released on 2011-03-15 with total page 874 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume is indexed by Thomson Reuters CPCI-S (WoS). The aim of this special volume is to facilitate the exchange of information on best practice for Photonics Materials and Devices, Optical Materials and Devices, NEMS/MEMS Materials and Devices, Electronic Materials and Instruments, Modeling, Simulation and Applications, etc. It will provide an opportunity for engineers and scientists in academia, industry and government to address the most innovative research and development ideas, together with their technical challenges, social and economic issues, and to discuss the ideas, results, work-in-progress and experience in all aspects of optical and electronic materials and their applications.
Download or read book Quality of Service in Wireless Networks Over Unlicensed Spectrum written by Klara Nahrstedt and published by Springer Nature. This book was released on 2022-06-01 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Synthesis Lecture presents a discussion of Quality of Service (QoS) in wireless networks over unlicensed spectrum. The topic is presented from the point of view of protocols for wireless networks (e.g., 802.11) rather than the physical layer point of view usually discussed for cellular networks in the licensed wireless spectrum. A large number of mobile multimedia wireless applications are being deployed over WiFi (IEEE 802.11) and Bluetooth wireless networks and the number will increase in the future as more phones, tablets, and laptops are equipped with these unlicensed spectrum wireless interfaces. Achieving QoS objectives in wireless networks is challenging due to limited wireless resources, wireless nodes interference, wireless shared media, node mobility, and diverse topologies. The author presents the QoS problem as (1) an optimization problem with different constraints coming from the interference, mobility, and wireless resource constraints and (2) an algorithmic problem with fundamental algorithmic functions within wireless resource management and protocols. Table of Contents: Preface / Basics of Quality of Service in Wireless Networks / QoS-Aware Resource Allocation / Bandwidth Management / Delay Management / Routing / Acknowledgment / References / Author Biography
Download or read book Medium Access Control in Ad Hoc Networks with Omni directional and Directional Antennas written by Yu Wang and published by . This book was released on 2004 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: An ad hoc network is a dynamic network formed on demand by a group of nodes without the aid of any pre-existing network infrastructure. An efficient and effective medium access control (MAC) protocol which regulates nodes access to the shared channel(s) is essential in an ad hoc network. Our work is focused on the throughput and fairness properties of existing omni-directional MAC protocols as well as enhancement of their performance with directional antennas via both analytical and simulation approaches. In the first part, we present the first analytical modeling of collision avoidance MAC protocols including the popular IEEE 802.11 MAC protocol in multi-hop ad hoc networks. We show that in ad hoc networks with a lot of hidden terminals, collision avoidance even if done correctly, can still limit achievable throughput significantly because of the much reduced spatial reuse. Then we advance the analytical modeling to evaluate those MAC protocols which use directional antennas and can achieve much higher throughput through directing transmissions and receptions to desired directions only. We show that the gain in spatial reuse outweighs that of collision avoidance and hence an aggressive all-directional scheme is more advantageous than other hybrid schemes that take conservative (or unnecessary) tradeoff between collision avoidance and spatial reuse. All the analytical work has provided very useful insight on the interaction between spatial reuse, interference reduction and collision avoidance that previous work lacked.
Download or read book MOBICOM written by and published by . This book was released on 2005 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A History based Scheduling Medium Access Protocol for Ad Hoc Networks written by Ye Bao and published by . This book was released on 2003 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ad Hoc Networks written by Shiwen Mao and published by Springer. This book was released on 2010-01-23 with total page 927 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ad hoc networks refer to the wireless networking paradigm that covers a variety of network forms for specific purposes, such as mobile ad hoc networks, sensor n- works, vehicular networks, underwater networks, underground networks, personal area networks, and home networks. The various forms of ad hoc networks promise a broad scope of applications in civilian, commercial, and military areas, which have led to significant new research problems and challenges, and have attracted great efforts from academia, industry, and government. This unique networking paradigm neces- tates re-examination of many established wireless networking concepts and protocols, and calls for developing new fundamental understanding of problems such as interf- ence, mobility, connectivity, capacity, and security, among others. While it is ess- tial to advance theoretical research on fundamentals and practical research on efficient algorithms and protocols, it is also critical to develop useful applications, experim- tal prototypes, and real-world deployments to achieve a practical impact on our so- ety for the success of this networking paradigm. The annual International Conference on Ad Hoc Networks (AdHocNets) is a new event that aims at providing a forum to bring together researchers from academia as well as practitioners from industry and government to meet and exchange ideas and recent research work on all aspects of ad hoc networks. As the first edition of this event, AdHocNets 2009 was successfully held in Niagara Falls, Ontario, Canada, during September 22–25, 2009.
Download or read book Improving Fairness and Utilisation in Ad Hoc Networks written by Mohamed Arabi and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ad hoc networks represent the current de-facto alternative for infrastructure-less environments, due to their self-configuring and resilience characteristics. Ad hoc networks flexibility benefits, such as unrestrained computing, lack of centralisation, and ease of deployment at low costs, are tightly bound with relevant deficiencies such as limited resources and management difficulty. Ad hoc networks witnessed high attention from the research community due to the numerous challenges faced when deploying such a technology in real scenarios. Starting with the nature of the wireless environment, which raises significant transmission issues when compared with the wired counterpart, ad hoc networks require a different approach when addressing the data link problems. Further, the high packet loss due to wireless contention, independent of network congestion, requires a different approach when considering quality of service degradation and unfair channel resources distribution among competing flows. Although these issues have already been considered to some extent by researchers, there is still room to improve quality of service by reducing the effect of packet loss and fairly distributing the medium access among competing nodes. The aim of this thesis is to propose a set of mechanisms to alleviate the effect of packet loss and to improve fairness in ad hoc networks. A transport layer algorithm has been proposed to overcome the effects of hidden node collisions and to reduce the impact of wireless link contention by estimating the four hop delay and pacing packet transmissions accordingly. Furthermore, certain topologies have been identified, in which the standard IEEE 802.11 faces degradation in channel utilisation and unfair bandwidth allocation. Three link layer mechanisms have been proposed to tackle the challenges the IEEE 802.11 faces in the identified scenarios to impose fairness in ad hoc networks through fairly distributing channel resources between competing nodes. These mechanisms are based on monitoring the collision rate and penalising the greedy nodes where no competing nodes can be detected but interference exists, monitoring traffic at source nodes to police access to the channel where only source nodes are within transmission range of each other, and using MAC layer acknowledgements to flag unfair bandwidth allocation in topologies where only the receivers are within transmission range of each other. The proposed mechanisms have been integrated into a framework designed to adapt and to dynamically select which mechanism to adopt, depending on the network topology. It is important to note that the proposed mechanisms and framework are not alternatives to the standard MAC protocol but are an enhancement and are triggered by the failure of the IEEE 802.11 protocol to distribute the channel resources fairly. All the proposed mechanisms have been validated through simulations and the results obtained from the experiments show that the proposed schemes fairly distribute channel resources fairly and outperform the performance of the IEEE 802.11 protocol in terms of channel utilisation as well as fairness.
Download or read book Handbook on Theoretical and Algorithmic Aspects of Sensor Ad Hoc Wireless and Peer to Peer Networks written by Jie Wu and published by CRC Press. This book was released on 2005-08-08 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt: The availability of cheaper, faster, and more reliable electronic components has stimulated important advances in computing and communication technologies. Theoretical and algorithmic approaches that address key issues in sensor networks, ad hoc wireless networks, and peer-to-peer networks play a central role in the development of emerging network
Download or read book Ad Hoc Wireless Networks written by C. Siva Ram Murthy and published by Pearson Education. This book was released on 2004-05-24 with total page 1050 pages. Available in PDF, EPUB and Kindle. Book excerpt: Practical design and performance solutions for every ad hoc wireless network Ad Hoc Wireless Networks comprise mobile devices that use wireless transmission for communication. They can be set up anywhere and any time because they eliminate the complexities of infrastructure setup and central administration-and they have enormous commercial and military potential. Now, there's a book that addresses every major issue related to their design and performance. Ad Hoc Wireless Networks: Architectures and Protocols presents state-of-the-art techniques and solutions, and supports them with easy-to-understand examples. The book starts off with the fundamentals of wireless networking (wireless PANs, LANs, MANs, WANs, and wireless Internet) and goes on to address such current topics as Wi-Fi networks, optical wireless networks, and hybrid wireless architectures. Coverage includes: Medium access control, routing, multicasting, and transport protocols QoS provisioning, energy management, security, multihop pricing, and much more In-depth discussion of wireless sensor networks and ultra wideband technology More than 200 examples and end-of-chapter problems Ad Hoc Wireless Networks is an invaluable resource for every network engineer, technical manager, and researcher designing or building ad hoc wireless networks.
Download or read book Computational Science and Its Applications ICCSA 2006 written by Marina L. Gavrilova and published by Springer Science & Business Media. This book was released on 2006 with total page 1281 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NETWORKING 2007 Ad Hoc and Sensor Networks Wireless Networks Next Generation Internet written by Ian F. Akyildiz and published by Springer Science & Business Media. This book was released on 2007-04-27 with total page 1278 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the 6th International IFIP-TC6 Networking Conference, NETWORKING 2007, held in Atlanta, GA, USA in May 2007. The 99 revised full papers and 30 poster papers were carefully reviewed and selected from 440 submissions. The papers are organized in topical sections on ad hoc and sensor networks: connectivity and coverage, scheduling and resource allocation, mobility and location awareness, routing, and key management; wireless networks: mesh networks, mobility, TCP, MAC performance, as well as scheduling and resource allocation; next generation inte.
Download or read book Ad hoc Mobile and Wireless Networks written by Xiang-Yang Li and published by Springer. This book was released on 2012-07-04 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the 11th International Conference on Ad-hoc, Mobile, and Wireless Networks, ADHOC-NOW 2012 held in Belgrade, Serbia, July 9-11, 2012. The 36 revised full papers presented were carefully reviewed and selected from 76 submissions. The accepted papers cover a wide spectrum of traditional networking topics ranging from routing to the application layer, to localization in various networking environments such as wireless sensor and ad-hoc networks, and give insights in a variety of application areas.
