Download or read book Optimal Random Access Protocols for Wireless Networks written by Man Hon Cheung and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Random Access Protocols written by Matteo Berioli and published by . This book was released on 2016 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: Random access represents possibly the simplest and yet one of the best known approaches for sharing a channel among several users. Since their introduction in the 1970s, random access schemes have been thoroughly studied and small variations of the pioneering Aloha protocol have since then become a key component of many communications standards, ranging from satellite networks to ad hoc and cellular scenarios. A fundamental step forward for this old paradigm has been witnessed in the past few years, with the development of new solutions, mainly based on the principles of successive interference cancellation, which made it possible to embrace constructively collisions among packets rather enduring them as a waste of resources. These new lines of research have rendered the performance of modern random access protocols competitive to that of their coordinated counterparts, paving the road for a multitude of new applications. This monograph explores the main ideas and design principles that are behind some of such novel schemes, and aims at offering to the reader an introduction to the analytical tools that can be used to model their performance. After reviewing some relevant results for the random access channel, the volume focuses on slotted solutions that combine the approach of diversity Aloha with successive interference cancellation, and discusses their optimisation based on an analogy with the theory of codes on graphs. The potential of modern random access is then further explored considering two families of schemes: the former based on physical layer network coding to resolve collisions among users, and the latter leaning on the concept of receiver diversity. Finally, the opportunities and the challenges encountered by random access solutions recently devised to operate in asynchronous, i.e., unslotted, scenarios are reviewed and discussed.

Download or read book Design and Analysis of Medium Access Protocols for Multi hop Wireless Networks written by Kezhu Hong and published by . This book was released on 2007 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Wireless Networks written by Savo G. Glisic and published by John Wiley & Sons. This book was released on 2016-07-22 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt: The third edition of this popular reference covers enabling technologies for building up 5G wireless networks. Due to extensive research and complexity of the incoming solutions for the next generation of wireless networks it is anticipated that the industry will select a subset of these results and leave some advanced technologies to be implemented later,. This new edition presents a carefully chosen combination of the candidate network architectures and the required tools for their analysis. Due to the complexity of the technology, the discussion on 5G will be extensive and it will be difficult to reach consensus on the new global standard. The discussion will have to include the vendors, operators, regulators as well as the research and academic community in the field. Having a comprehensive book will help many participants to join actively the discussion and make meaningful contribution to shaping the new standard.

Download or read book Wireless Networks Model and Optimization Based Approaches to Clock Synchronization Random Access MAC and Video Streaming written by Nikolaos M. Freris and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We, via a model and optimization-based approach, address three issues related to wireless networks: clock synchronization, medium access control (MAC) and scalable video streaming. In Chapter 2 we develop, study and simulate a new model-based distributed network clock synchronization protocol. In a network of clocks, a given node is taken as reference and is associated with the time evolution t. We introduce and analyze a stochastic model for clocks, in which the relative speedup of a clock with respect to the reference node, called the skew, is characterized by an exponential transformation of an Orstein-Uhlenbeck process. We study the properties of our model, namely moment and sample path properties of the stochastic processes, and calculate its Allan variance. We show how our model can be used to translate the time of a clock to another clock's units. We study the problem of synchronizing clocks in a network, which amounts to estimating the instantaneous relative skews and relative offsets, i.e., the differences in the clock readouts, by exchange of time-stamped packets between pairs of nodes in the network. Based on a stochastic model for delays, we derive a scheme for obtaining relative skew measurements in a communication link by sending two time-stamped packets from node i to node j in order to obtain a noisy measurement of their relative skew. We develop an algorithm for filtering relative skew measurements across a link (i,j) in order to estimate the logarithm of the relative skew. We study the properties of the algorithms and provide theoretical guarantees on their performance. We also develop an online, centralized, model-based, asynchronous skew estimation algorithm for optimal filtering of the time-stamps in the entire network, as well as an efficient distributed suboptimal scheme which demonstrates near-optimal performance in simulations. Furthermore, we study some implementation issues, and present a scheme for pairwise relative offset estimation given skew estimates. We use the distributed asynchronous algorithm to obtain nodal offset estimates from relative offset estimates. We combine our findings into developing a new protocol for clock synchronization, namely the Model-Based Clock Synchronization Protocol (MBCSP). We present a comparative simulation study of its performance versus the leading scheme by Solis et al. (2006); the results show that MBCSP performs better in terms of skew, offset and delay estimation. Finally, we have performed trace-driven simulation based on time-stamps obtained from Berkeley motes. Our scheme outperforms that of Solis et al. by 45%, where we used the accuracy in predicting the receipt time-stamp at the sender as the clock synchronization metric. In Chapter 3, we study random access based MAC in the framework of network utility maximization (NUM). There has been much recent interest in protocol design for wireless networks based on maximizing a network utility function. A significant advance is the observation that a decomposition of the Lagrangian suggests an approach where transmissions are scheduled to minimize back-pressure. However, a satisfactory MAC protocol that can realize such a scheduling algorithm is notably missing, and we develop one potential scheme. We present a candidate random access MAC protocol that extends an existing algorithm by Gupta and Stolyar (2006) in calculating the access probabilities. We also consider the online adaptation of access probabilities using local information about queue lengths and active links. We provide OPNET simulation results to compare the performance of our scheme with the leading schemes. We estimate the capacity region of our scheme by simulation for various topologies and multiple flows. Our simulation studies indicate that our extension in conjunction with an implementation of back-pressure significantly outperforms the slotted-time algorithm of Gupta and Stolyar (2006). In Chapter 4, we present performance bounds for random access based MAC using carrier-sense multiple access (CSMA). In recent work, it was shown that a distributed CSMA-based MAC protocol is throughput-optimal which, in turn, implies that the class of controlled distributed random access MAC protocols can support the entire capacity region. It is challenging to study the performance of such schemes in terms of mean delays and compare it with some known results on the performance of centralized scheduling. We modify the model of Jiang and Walrand (2008) to obtain Markov chain models that incorporate the queue lengths as well as the information about the independent set, for single-hop networks. We show that the delay of the new models yields an upper bound on the delay of the original models. We derive upper and lower bounds on the mean total delay at the steady-state, and show that these bounds coincide with those for max-weight scheduling. Finally, we develop a method of deriving upper and lower bounds for random-access schemes by using linear programs (LPs). We present an optimization program for minimizing the upper bounds. In Chapter 5, we consider multihomed scalable video streaming systems where each video is concurrently transmitted over several access networks to a client. The problem is to determine which video packets of a video stream to transmit, and associate each video packet with an access network, so that the video quality at the client is maximized under measured network conditions. We present a network model and a video distortion model to capture the network conditions and video distortion characteristics, respectively. We develop a mathematical formulation to find the streaming strategy for maximizing the average video quality at the client. While the formulation can be optimally solved using exhaustive search or dynamic programming, doing so takes a prohibitively long time, and is not practical for real-time video streaming servers. In order to efficiently solve the problem in real time, we propose several suboptimal convex problems along with two heuristic algorithms. We conduct extensive trace-driven simulations to evaluate the algorithms using real network conditions and actual scalable video streams. We compare our algorithms against the rate control algorithms defined in the Datagram Congestion Control Protocol (DCCP) standard. The simulation results show that our algorithms significantly outperform current systems while being TCP-friendly. For example, compared to DCCP, our algorithms achieve at least 10 dB quality improvement and result in up to 83% packet delivery delay reduction. Finally, we study the trade-off between efficiency and optimality: One of the heuristic algorithms runs faster and is suitable for large-scale streaming systems, while the other one achieves better video quality and is more appropriate for smaller streaming servers. The convex programming approach demonstrates a good trade-off between running time and performance.

Download or read book Modern Random Access Protocols written by Matteo Berioli and published by Foundations and Trends (R) in Networking. This book was released on 2016-11-17 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern day wireless communication systems rely heavily on the random access schemes that were originally developed in the 1970s. The pioneering Aloha protocol has become a key component of many communications standards, ranging from satellite networks to ad hoc and cellular scenarios. Recent developments, however, have seen a fundamental leap forward based on using the principles of successive interference cancellation. The modern random access protocols using these new techniques have opened up a wealth of new applications. This tutorial style monograph explores the main ideas and design principles that are behind some of these novel schemes. It introduces the reader to the analytical tools used to model such performance. Focussing on slotted solutions it shows how Aloha can be combined with successive interference cancellation and optimized using the theory of codes on graphs. These techniques are illustrated in applications using physical layer network coding to resolve collisions among users and receiver diversity. It concludes by introducing the reader to the recently asynchronous (or unslotted) schemes. Modern Random Access Protocols is a comprehensive and erudite introduction to a set of techniques that will form part of many future modern communication or networked system.

Download or read book Optimization in the Natural Sciences written by Alexander Plakhov and published by Springer. This book was released on 2015-06-10 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the 30th Euro Mini-Conference, EmC-ONS 2014, held in Aveiro, Portugal, in February 2014. The 13 revised full papers presented were carefully reviewed and selected from 70 submissions. The papers are organized in topical sections on dynamical systems; optimization and applications; modeling and statistical techniques for data analysis.

Download or read book Energy and Spectrum Efficient Wireless Network Design written by Guowang Miao and published by Cambridge University Press. This book was released on 2015 with total page 387 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides the fundamental principles and practical tools needed to design next-generation wireless networks that are both energy- and spectrum-efficient.

Download or read book Medium Access Control in Wireless Networks written by Hongyi Wu and published by Nova Publishers. This book was released on 2008 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wireless technologies and applications are becoming one of the fastest growing and most promising areas in recent years. To accommodate data transmission by multiple stations sharing the scarce wireless bandwidth, a medium access control (MAC) protocol plays a crucial role in scheduling packet transmission fairly and efficiently. The emerging wireless networks, such as ad-hoc networks, sensor networks or mesh networks, are mostly multi-hop based and in distributed manner, which brings a lot of problems and challenges in designing fine-tuned MAC protocols tailored for modern wireless network. In this book, the authors give complete and in-depth overviews to the classic medium access control algorithms and the related protocols, as well as their applications in various wireless data networks especially the most successful Wireless Local Area Networks (WLAN). The book consists of three major parts. Part I of this book, including Chapters 1-7, is emphasising on the fundamentals of medium access control algorithms and protocols. Chapter 1 provides an introduction to the wireless networks, such as overview of wireless networks, problems and challenges of the wireless networks, and the classifications of MAC protocols as well as the performance metrics. Chapter 2 introduces important collision resolution algorithms applied in medium access controls, for example, the splitting algorithm and the backoff algorithm. Chapter 3 reviews the hybrid access control algorithms that combine both contention and allocation schemes. A series of important collision avoidance schemes are introduced in Chapters 4-7 respectively, with a specific design goal covered in each chapter. Chapter 4 focuses on the multi-channel MAC protocols for collision avoidance; Chapter 5 introduces the concepts of power control and power management in medium access control and how they can be applied in MAC protocol design; Chapter 6 presents how to provide Quality-of- Service (QoS) to multimedia wireless networks, in either centralised or distributed manner; and Chapter 7 explains how the smart antennas can be applied in the medium access control to provide high channel throughput and low packet collision.

Download or read book Throughput Optimization in Multi hop Wireless Networks with Random Access written by Md. Forkan Uddin and published by . This book was released on 2011 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research investigates cross-layer design in multi-hop wireless networks with random access. Due to the complexity of the problem, we study cross-layer design with a simple slotted ALOHA medium access control (MAC) protocol without considering any network dynamics.

Download or read book Wireless Systems and Mobility in Next Generation Internet written by Gabriele Kotsis and published by Springer. This book was released on 2005-02-25 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Internet is subject to permanent modi?cations and to continuous restr- turing. This is primarily due to the tremendous rise in demand for bandwidth by the ever increasing number of users. When compared to the early years of the Internet the quality of the services o?ered had to be signi?cantly improved in di?erent respects (delay, network and service availability, jitter,. . . )inorder to satisfy the needs of many new applications. Within the last decade two new developments have contributed to many new opportunities, as well as to a need for intensive research and development: – the increased mobility of users together with the desire for ubiquitous hi- quality access to all o?ered services, at reasonable cost; – the use of wireless communication. Despite their relatively low capacity (when compared with ?xed backbone n- works) the use of radio links supports the ubiquitous availability of Internet services in a quasiperfect way. A considerable amount of research and development activities are currently - ing on worldwide in order to adapt Internet services to the particular needs of mobile users and of wireless communication links. These questions were - tensively discussed at the ?rst workshop organized by the EURO-NGI Network of Excellence (‘Next Generation Internet’), which has been funded by the - ropean Union since January 2004 under their IST programme.

Download or read book Optimization of Computer Networks written by Pablo Pavón Mariño and published by John Wiley & Sons. This book was released on 2016-05-02 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the design and optimization of computer networks applying a rigorous optimization methodology, applicable to any network technology. It is organized into two parts. In Part 1 the reader will learn how to model network problems appearing in computer networks as optimization programs, and use optimization theory to give insights on them. Four problem types are addressed systematically – traffic routing, capacity dimensioning, congestion control and topology design. Part 2 targets the design of algorithms that solve network problems like the ones modeled in Part 1. Two main approaches are addressed – gradient-like algorithms inspiring distributed network protocols that dynamically adapt to the network, or cross-layer schemes that coordinate the cooperation among protocols; and those focusing on the design of heuristic algorithms for long term static network design and planning problems. Following a hands-on approach, the reader will have access to a large set of examples in real-life technologies like IP, wireless and optical networks. Implementations of models and algorithms will be available in the open-source Net2Plan tool from which the user will be able to see how the lessons learned take real form in algorithms, and reuse or execute them to obtain numerical solutions. An accompanying link to the author’s own Net2plan software enables readers to produce numerical solutions to a multitude of real-life problems in computer networks (www.net2plan.com).

Download or read book Resource Allocation in Next Generation Wireless Networks written by Wayne Li and published by Nova Publishers. This book was released on 2006 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Next generation wireless and mobile communication systems are rapidly evolving to satisfy the demands of various network users. Due to the great success and enormous impact of IP networks, high-speed transmission is now possible for both indoor and outdoor wireless systems, internet access and web browsing have become the ruling paradigm for next generation system. It is envisioned that new generation wireless networks and hand-held terminals will support a wide variety of multimedia services such as multimedia web browsing, video and news on demand, mobile office system, stock market information, and so on, to mobile users anywhere, anytime in an uninterrupted and seamless way with low-powered handsets. The characteristics of wireless links, as well as the desire to maintain connectivity while on the move, offer significant challenges to provisioning quality of service and the related performance is of central interest. Since the resources (such as time, frequency and code) in the wireless segments of such networks are very limited, over-dimensioning the network resource is equivalent to poor capital investment, while congestion at busy hours could mean lost calls and lost revenues. It is therefore critical for wireless network designers to utilise these resources efficiently and effectively. In response to the above demand for next generation wireless and mobile communication systems, this book aims at providing a timely and concise reference of the current activities and findings in the relevant technical fields. The primary goal is to address the key technical issues pertaining to the integrated new systems and present novel technical contributions. The book contains 14 invited chapters from prominent researchers working in this area around the world.

Download or read book Embedded Computing Systems Applications Optimization and Advanced Design written by Khalgui, Mohamed and published by IGI Global. This book was released on 2013-04-30 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Embedded computing systems play an important and complex role in the functionality of electronic devices. With our daily routines becoming more reliant on electronics for personal and professional use, the understanding of these computing systems is crucial. Embedded Computing Systems: Applications, Optimization, and Advanced Design brings together theoretical and technical concepts of intelligent embedded control systems and their use in hardware and software architectures. By highlighting formal modeling, execution models, and optimal implementations, this reference source is essential for experts, researchers, and technical supporters in the industry and academia.

Download or read book Network Control and Optimization written by Tijani Chahed and published by Springer. This book was released on 2007-10-24 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book constitutes the refereed proceedings of the First Euro-FGI International Conference on Network Control and Optimization, NET-COOP 2007, held in Avignon, France in June 2007. The 22 revised full papers presented together with nine invited lectures address all current issues in network control and optimization, ranging from performance evaluation and optimization of general stochastic networks to more specific targets.

Download or read book A Stable Random Access Protocol for Wireless Data Networks written by Anil Kumar Donthula and published by . This book was released on 2003 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wireless Networking written by Anurag Kumar and published by Elsevier. This book was released on 2008-05-09 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, the world has witnessed an explosion in the development and deployment of new wireless network technologies. From cellular mobile telephony to the ubiquitous “WiFi networks in coffee-shops and airports, to the emerging WiMAX wireless broadband access networks, the menu of wireless access systems has become so comprehensive that wireline access to user devices may soon become a relic of the past. Wireless Networking serves as a one-stop view of cellular, WiFi, and WiMAX networks, as well as the emerging wireless ad hoc and sensor networks. Rather than provide descriptive accounts of these technologies and standards, the book emphasizes conceptual perspectives on the modeling, analysis, design and optimization of such networks. Furthermore, the authors present wireless networking within the unifying framework of resource allocation, using simple abstractions of the underlying physical wireless communication. In short, Wireless Networking is an in-depth, exhaustive, and invaluable asset to anyone working in this rapidly evolving field. Goes beyond descriptive and qualitative treatments, by presenting the foundations underlying the various wireless networking technologies Provides abstractions, models and analyses of established and emerging wireless networks, thereby supplying the reader with a conceptual and quantitative treatment, thus ensuring longevity of the learning from this material Aids comprehension by including over 120 figures, four appendices on the mathematics of the various models, several inline exercises, and extensive problem sets at the end of each chapter