Download or read book Clock Synchronization and Dominating Set Construction in Ad Hoc Wireless Networks written by Dong Zhou and published by . This book was released on 2005 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Ad Hoc wireless networks have been gaining importance in the communication world for the past decade. Wireless network extends the access to the network by removing the restriction of physical wires. Ad hoc network further improves the network coverage and availability to places without infrastructure support. Clock synchronization and dominating set are two of the fundamental issues in the wireless ad hoc networks. They are important for the correctness and/or performance of many protocols and applications. We focus on IEEE 802.11 wireless ad hoc networks in this dissertation due to the wide deployments of 802.11 networks. The theories and practices are definitely extensible to other types of ad hoc networks. IEEE 802.11 wireless network depends heavily on the distribution of timing information to all the stations in the network. Clock synchronization is important for frequency hopping, power saving and wireless medium reservation. We review the Timing Synchronization Function (TSF) of Ad Hoc mode defined in the 802.11 standard. It is well-known that the 802.11 TSF is not scalable. We carefully analyze the root causes of the scalability problem and design new schemes to overcome the problem. Our new schemes show great improvement over the 802.11 TSF and other solutions in the fields. Our solutions have nice characteristics: scalable, accurate, bounded and adaptive to station mobility. We are able to control the maximum clock differences under 25 micro seconds and 50 micro seconds in single hop and multihop networks respectively. The performance improvement is at least 200% or more compared with the current solutions. Dominating set has been widely used in multihop ad hoc networks (MANET) by numerous routing, broadcast and collision avoidance protocols. The problem to construct a minimum sized dominating set is known to be NP-hard. We propose a protocol that is simple, distributed, inexpensive, and adaptive to station mobility. We show that our protocol can construct dominating set using 35% to 60% less nodes than other distributed dominating set protocols. We study and address two of the fundamental and difficult problems in ad hoc wireless networks. Our solutions show significant improvements over the current solutions. Our work provides solid foundations to other important problems: routing, power saving, frequency hopping, media access scheduling, and broadcast storm mitigation.

Download or read book Opportunistic Clock Synchronization for Ad Hoc Networks written by Maria B. Carrasco and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An ad hoc network is a collection of computing nodes communicating over wireless channels without relying on any fi xed infrastructure such as servers and towers. Such networks are useful in rescue operations, and in rural and military settings. Clock synchronization is an essential building block for many ad hoc wireless network applications. It provides the participating computing nodes with logical clocks whose di erences can be bounded. Several traditional distributed clock synchronization algorithms use strict communication structures such as spanning trees. In such protocols, a node corrects its logical clock when it receives a new time-stamped message from its parent. In this thesis, we present a new clock synchronization protocol that exploits the broadcast medium in wireless networks, allowing nodes to opportunistically correct their logical clocks in order to converge to a reference time provided by a designated root node. Our protocol does not rely on a communication structure and is lightweight due to its low overhead. We also propose a variation of our opportunistic protocol, which further reduces overhead through randomized broadcast techniques. Our simulation-based experimental evaluation of the protocols illustrates that our opportunistic algorithms improve the accuracy of the nodes' logical clocks, when compared to a tree-based protocol. However, we show that the level of improvement is a function of the density of the wireless network. Additionally, the results show that our algorithms can produce around half the overhead, compared to an existing protocol that achieves higher levels of precision.

Download or read book Time Synchronization in Ad Hoc Wireless Networks written by Andrew Reid and published by . This book was released on 2008 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Simple Protocol for Dominating Set Construction in Mobile Ad Hoc Networks written by Donghoon Kim and published by . This book was released on 2003 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Local Construction of Connected Dominating Sets in Wireless Ad Hoc Networks written by Fei Dai and published by . This book was released on 2005 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Guaranteed Time Synchronization in Wireless and Ad hoc Networks written by Philipp Blum and published by . This book was released on 2005 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Protocols and Architectures for Wireless Sensor Networks written by Holger Karl and published by John Wiley & Sons. This book was released on 2007-10-08 with total page 531 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn all you need to know about wireless sensor networks! Protocols and Architectures for Wireless Sensor Networks provides a thorough description of the nuts and bolts of wireless sensor networks. The authors give an overview of the state-of-the-art, putting all the individual solutions into perspective with one and other. Numerous practical examples, case studies and illustrations demonstrate the theory, techniques and results presented. The clear chapter structure, listing learning objectives, outline and summarizing key points, help guide the reader expertly through the material. Protocols and Architectures for Wireless Sensor Networks: Covers architecture and communications protocols in detail with practical implementation examples and case studies. Provides an understanding of mutual relationships and dependencies between different protocols and architectural decisions. Offers an in-depth investigation of relevant protocol mechanisms. Shows which protocols are suitable for which tasks within a wireless sensor network and in which circumstances they perform efficiently. Features an extensive website with the bibliography, PowerPoint slides, additional exercises and worked solutions. This text provides academic researchers, graduate students in computer science, computer engineering, and electrical engineering, as well as practitioners in industry and research engineers with an understanding of the specific design challenges and solutions for wireless sensor networks. Check out www.wiley.com/go/wsn for accompanying course material! "I am deeply impressed by the book of Karl & Willig. It is by far the most complete source for wireless sensor networks...The book covers almost all topics related to sensor networks, gives an amazing number of references, and, thus, is the perfect source for students, teachers, and researchers. Throughout the book the reader will find high quality text, figures, formulas, comparisons etc. - all you need for a sound basis to start sensor network research." Prof. Jochen Schiller, Institute of Computer Science, Freie Universität Berlin

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2008 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Network Analysis and its Applications written by Evangelos Kranakis and published by Springer Science & Business Media. This book was released on 2012-10-24 with total page 415 pages. Available in PDF, EPUB and Kindle. Book excerpt: As well as highlighting potentially useful applications for network analysis, this volume identifies new targets for mathematical research that promise to provide insights into network systems theory as well as facilitating the cross-fertilization of ideas between sectors. Focusing on financial, security and social aspects of networking, the volume adds to the growing body of evidence showing that network analysis has applications to transportation, communication, health, finance, and social policy more broadly. It provides powerful models for understanding the behavior of complex systems that, in turn, will impact numerous cutting-edge sectors in science and engineering, such as wireless communication, network security, distributed computing and social networking, financial analysis, and cyber warfare. The volume offers an insider’s view of cutting-edge research in network systems, including methodologies with immense potential for interdisciplinary application. The contributors have all presented material at a series of workshops organized on behalf of Canada’s MITACS initiative, which funds projects and study grants in ‘mathematics for information technology and complex systems’. These proceedings include papers from workshops on financial networks, network security and cryptography, and social networks. MITACS has shown that the partly ghettoized nature of network systems research has led to duplicated work in discrete fields, and thus this initiative has the potential to save time and accelerate the pace of research in a number of areas of network systems research.

Download or read book Computing and Combinatorics written by Lusheng Wang and published by Springer Science & Business Media. This book was released on 2005-08-04 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt: The refereed proceedings of the 11th Annual International Computing and Combinatorics Conference, COCOON 2005, held in Kunming, China in August 2005. The 96 revised full papers presented together with abstracts of 3 invited talks were carefully reviewed and selected from 353 submissions. The papers cover most aspects of theoretical computer science and combinatorics related to computing and are organized in topical sections on bioinformatics, networks, string algorithms, scheduling, complexity, steiner trees, graph drawing and layout design, quantum computing, randomized algorithms, geometry, codes, finance, facility location, graph theory, graph algorithms.

Download or read book Handbook of Sensor Networks written by Ivan Stojmenovic and published by John Wiley & Sons. This book was released on 2005-09-19 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: The State Of The Art Of Sensor Networks Written by an international team of recognized experts in sensor networks from prestigious organizations such as Motorola, Fujitsu, the Massachusetts Institute of Technology, Cornell University, and the University of Illinois, Handbook of Sensor Networks: Algorithms and Architectures tackles important challenges and presents the latest trends and innovations in this growing field. Striking a balance between theoretical and practical coverage, this comprehensive reference explores a myriad of possible architectures for future commercial, social, and educational applications, and offers insightful information and analyses of critical issues, including: * Sensor training and security * Embedded operating systems * Signal processing and medium access * Target location, tracking, and sensor localization * Broadcasting, routing, and sensor area coverage * Topology construction and maintenance * Data-centric protocols and data gathering * Time synchronization and calibration * Energy scavenging and power sources With exercises throughout, students, researchers, and professionals in computer science, electrical engineering, and telecommunications will find this an essential read to bring themselves up to date on the key challenges affecting the sensors industry.

Download or read book New Challenges in Computational Collective Intelligence written by Radoslaw Katarzyniak and published by Springer Science & Business Media. This book was released on 2009-08-27 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Collective intelligence has become one of major research issues studied by today’s and future computer science. Computational collective intelligence is understood as this form of group intellectual activity that emerges from collaboration and compe- tion of many artificial individuals. Robotics, artificial intelligence, artificial cognition and group working try to create efficient models for collective intelligence in which it emerges from sets of actions carried out by more or less intelligent individuals. The major methodological, theoretical and practical aspects underlying computational collective intelligence are group decision making, collective action coordination, collective competition and knowledge description, transfer and integration. Obviously, the application of multiple computational technologies such as fuzzy systems, evo- tionary computation, neural systems, consensus theory, knowledge representation etc. is necessary to create new forms of computational collective intelligence and support existing ones. Three subfields of application of computational technologies to support forms of collective intelligence are of special attention to us. The first one is semantic web treated as an advanced tool that increases the collective intelligence in networking environments. The second one covers social networks modeling and analysis, where social networks are this area of in which various forms of computational collective intelligence emerges in a natural way. The third subfield relates us to agent and mul- agent systems understood as this computational and modeling paradigm which is especially tailored to capture the nature of computational collective intelligence in populations of autonomous individuals.

Download or read book Time Synchronization and Periodic Aggregation in Wireless Ad hoc Sensor Networks written by Saurabh Ganeriwal and published by . This book was released on 2003 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Clock Synchronization for Mobile Ad Hoc Networks written by Rajan Chandra and published by . This book was released on 2003 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings written by and published by . This book was released on 2005 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interval based Time Synchronization for Mobile Ad hoc Networks written by Lennart Meier and published by . This book was released on 2006 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Algorithmic Aspects of Wireless Sensor Networks written by Sotiris Nikoletseas and published by Springer. This book was released on 2007-01-26 with total page 227 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the reviewed proceedings of the Second International Workshop on Algorithmic Aspects of Wireless Sensor Networks, ALGOSENSORS 2006, held in Venice, Italy in July 2006, in association with ICALP 2006. Topics addressed are foundational and algorithmic aspects of the wireless sensor networks research. In particular, ALGOSENSORS focuses on abstract models, complexity-theoretic results and lower-bounds.