Download or read book S curit dans les r seaux sans fil Norme IEEE 802 11 written by Mühlethaler and published by . This book was released on with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MIMO Channel Hardware Simulator for LTE and 802 11ac Wireless Communication Systems written by Bachir Habib and published by . This book was released on 2013 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pour évaluer les performances des systèmes de communications sans fil, un simulateur matériel de canal MIMO (Multiple-Input Multiple-Output) est réalisé pour les nouveaux systèmes de communication. Il fournit la vitesse de traitement nécessaire et permet d’évaluer les performances en temps réel. Il permet de comparer les différents systèmes dans les mêmes conditions souhaitées. Les objectifs de ce travail concernent principalement les modèles de canal MIMO et l'architecture de bloc numérique du simulateur matériel.Le simulateur matériel conçu peut être configuré avec les nouveaux réseaux radio-mobiles (LTE) et les réseaux locaux sans fil (WLAN 802.11ac). Il utilise des modèles de canaux standardisés, comme le TGn IEEE 802.11n et le 3GPP-LTE, ou des résultats de mesures effectuées avec un sondeur de canalMIMO conçu et réalisé dans notre laboratoire. Récemment, le sondeur de canal a été utilisé au cours de campagnes de mesure pour des environnements à bord d’un navire et de l’extérieur-vers-l’intérieur (outdoor-to-indoor). Un algorithme est proposé pour que les réponses impulsionnelles mesurées soient compatibles avec la bande des signaux LTE. En outre, le modèle de Kronecker avec des évanouissements de Rayleigh est utilisé pour obtenir un canal variant dans le temps.Le simulateur doit être capable de reproduire différents types d'environnement. Dans ce contexte, de nombreux scénarios ont été proposés. Ils considèrent le mouvement à l'intérieur et à l'extérieur pour des environnements et des réseaux hétérogènes. Un algorithme est proposé et analysé pour basculer entre les environnements d’une manière continue. Ces réseaux offrent des services à travers un réseau cellulaire à l'aide du LTE et sont capables de maintenir le service lors du passage à un réseau local sans fil WLAN 802.11ac.Deux architectures pour le bloc numérique du simulateur matériel sont proposées. La première opère dans le domaine fréquentiel en utilisant des modules de transformée de Fourier rapide (FFT/IFFT). Dans ce contexte, une nouvelle architecture fréquentielle améliorée qui fonctionne avec des signaux d'entrée de longue durée est proposée. La seconde opère dans le domaine temporel en utilisant des filtres à Réponse Impulsionnelle Finie (FIR).Les architectures ont été implémentées sur des circuits programmables (FPGA : Field Programmable Gate Array) Virtex-IV de Xilinx. Leurs occupations sur FPGA, la précision des signaux de sortie et leur latence sont analysées et comparées. De plus, une solution basée sur un facteur d’échelle automatique (ASF: Auto-Scale Factor) est introduite pour augmenter la précision des signaux de sortie.
Download or read book Analyse de la consommation d nergie des r seaux sans fil IEEE 802 11 au niveau MAC written by Teck Aguilar Chiu and published by . This book was released on 2005 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book R seaux v hiculaires Mod les et algorithmes written by LABIOD Houda and published by Lavoisier. This book was released on 2013-09-01 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: L’émergence des systèmes de transport intelligents est due principalement aux grands progrès technologiques dans les domaines des protocoles de communication sans fil, des systèmes embarqués et temps réel. Très prometteurs, ces derniers permettront d’offrir un large éventail de nouvelles applications, de nouveaux véhicules communicants et de définir un éco-système de mobilités diversifiées. Les caractéristiques inhérentes à ces systèmes posent de nouveaux challenges en termes de protocoles et d’architectures de communications. Les réseaux véhiculaires connaissent des évolutions récentes : cet ouvrage propose d’en traiter les problèmes critiques, à savoir le contrôle de congestion, le routage, le clustering, l’interconnexion entre le réseau véhiculaire et les réseaux LTE/LTE Advanced, le contrôle du trafic routier ou encore la simulation à travers les outils et la génération de traces de mobilité. D’approche analytique, cet ouvrage se présente comme la genèse d’un nouveau domaine qui est en train de bouleverser les modèles de transports dans nos sociétés.
Download or read book Wireless and Mobile Network Security written by Hakima Chaouchi and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a thorough examination and analysis of cutting-edge research and security solutions in wireless and mobile networks. It begins with coverage of the basic security concepts and fundamentals which underpin and provide the knowledge necessary for understanding and evaluating security issues, challenges, and solutions. This material will be of invaluable use to all those working in the network security field, and especially to the many people entering the field. The next area of focus is on the security issues and available solutions associated with off-the-shelf wireless and mobile technologies such as Bluetooth, WiFi, WiMax, 2G, and 3G. There is coverage of the security techniques used to protect applications downloaded by mobile terminals through mobile cellular networks, and finally the book addresses security issues and solutions in emerging wireless and mobile technologies such as ad hoc and sensor networks, cellular 4G and IMS networks.
Download or read book Wireless Ad Hoc and Sensor Networks written by Houda Labiod and published by John Wiley & Sons. This book was released on 2010-01-05 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two new fields have recently appeared: mobile ad hoc networks and sensor networks. The emergence of these very promising systems is mainly due to great technological progress in the field of wireless communication protocols; these will make it possible to offer a broad range of new applications in both civilian and militarian domains. The inherent characteristics of these systems imply new challenges. This book deals with several relevant fields related to the evolution of these spontaneous and self-organized networks. The authors tackle critical problems such as the design of unicast/multicast routing protocols, the support of the quality of service, the security mechanisms for routing and data transmission, the service discovery, the techniques of clustering/self-organization, the mobility of code and the fault-tolerance techniques. The discussion adopts an analysis-oriented approach which aims to cover the current cutting-edge aspects of these fields and to highlight some potential future development, making it essential reading for anyone wishing to gain a better understanding of these exciting new areas.
Download or read book D veloppement d un simulateur sans fil multi antennes written by Marouane Loussayef and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Les systèmes de communication sans fil de nouvelle génération nécessitent des techniques avancées afin de supporter un nombre élevé d'usagers et d'augmenter le débit sans avoir besoin de largeur de bande additionnelle. Une de ces techniques est l'utilisation des systèmes MIMO (Multi-Input, Multi-Output). De tels systèmes augmentent le débit, la portée et la robustesse aux évanouissements du canal sans consommer de largeur de bande additionnelle. Dans cette thèse, nous modélisons la norme 802.11 pour les réseaux ad-hoc à accès MIMO. Nous dégageons des scénarios de simulation permettant de mettre en lumière certaines situations problématiques des réseaux sans-fil. Ce mémoire introduit dans un premier temps le canal sans fil et les spécifications de la norme 802.11. Dans un deuxième temps, nous introduisons le simulateur réseau NS-2 ainsi que certaines simulations des réseaux ad-hoc utilisant la norme 802.11. Et pour finir on a testé notre extension MIMO par des scénarios de simulation de réseaux étendus.
Download or read book Real 802 11 Security written by Jon Edney and published by Addison-Wesley Professional. This book was released on 2004 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes new approaches to wireless security enabled by the recent development of new core technologies for Wi-Fi/802.11. It shows how the new approaches work and how they should be applied for maximum effect. For system administrators, product designers, or advanced home users.
Download or read book Personal Wireless Communications Pwc 05 Proceedings Of The 10th Ifip Conference written by Pascal Lorenz and published by World Scientific. This book was released on 2005-07-07 with total page 543 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 10th IFIP International Conference on Personal Wireless Communications covers a wide spectrum: wireless sensors, signalization, traffic and QoA in wireless networks, Ad-Hoc, IEEE 802.11, cellular and mobile networks. This volume offers a large range of solutions to key problems in wireless networking and explores challenging avenues for industrial research and development. It is accessible to engineers, practitioners, and scientists as well as industry professionals from manufacturers to service providers.
Download or read book End to End Quality of Service written by Abdelhamid Mellouk and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: A modern communication network can be described as a large, complex, distributed system composed by higher interoperating, smaller sub-systems. Today, the proliferation and convergence of different types of wired, wireless, and mobile networks are crucial for the success of the next generation networking. However, these networks can hardly meet the requirements of future integrated-service networks, and are expected to carry multimedia traffic with various Quality of Experience (QoE) and Quality of Service (QoS) requirements. Providing all relevant QoS/QoE issues in these heterogeneous networks is then an important challenge for telecommunication operators, manufacturers, and companies. The impressive emergence and the important demand of the rising generation of real-time Multi-service (such as Data, Voice VoD, Video-Conference, etc.) over communication heterogeneous networks, require scalability while considering a continuous QoS. This book presents and explains all the techniques in new generation networks which integrate efficient global control mechanisms in two directions: (1) maintain QoS requirements in order to maximize network resources utilization, and minimize operational costs on all the types of wired-wireless-mobile networks used to transport traffic, and (2) mix the QoS associated with home, access, and core networks in order to provide Quality of Service/Quality of Experience expected by users of new services.
Download or read book Management Control and Evolution of IP Networks written by Guy Pujolle and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internet Protocol (IP) networks have, for a number of years, provided the basis for modern communication channels. However, the control and management of these networks needs to be extended so that the required Quality of Service can be achieved. Information about new generations of IP networks is given, covering the future of pervasive networks (that is, networks that arealways present), Wi-Fi, the control of mobility and improved Quality of Service, sensor networks, inter-vehicle communication and optical networks.
Download or read book Cryptographie principes et mises en uvre 2 me dition revue et augment e written by BARTHELEMY Pierre and published by Lavoisier. This book was released on 2012-04-16 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quels sont les enjeux de la cryptographie moderne ? Quels sont ses objets, son langage ? Quelles sont les solutions actuelles aux problèmes de confidentialité, d'authentification et d'anonymat ? Quel degré de confiance peut-on accorder à ces solutions ? Cette seconde édition, enrichie et mise à jour, propose un panorama des outils et procédés de la cryptographie. Après avoir présenté et analysé les méthodes, cet ouvrage offre une description précise des techniques mathématiques indispensables et des principales primitives cryptographiques. Les fonctionnalités de base comme le chiffrement, la signature ou l'authentification, sont étudiées dans le cadre de la cryptographie à clé publique ou secrète. Cryptographie analyse également l'interaction entre ces notions ainsi que leurs mises en oeuvre dans des protocoles généraux et dans des applications concrètes. Il s'intéresse aux attaques contre les systèmes cryptographiques y compris celles par canaux cachés et par injection de fautes. Il aborde le domaine désormais indispensable des preuves de sécurité.
Download or read book Annales des t l communications written by and published by . This book was released on 2007 with total page 1472 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Secure Routing and Medium Access Protocols in Wireless Multi hop Networks written by Soufiene Djahel and published by GRIN Verlag. This book was released on 2011-10-28 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2011 in the subject Computer Science - Internet, New Technologies, Lille 1 University (Laboratoire d'Informatique Fondamentale de Lille), course: Security in Wireless Multi-hop Networks, language: English, abstract: While the rapid proliferation of mobile devices along with the tremendous growth of various applications using wireless multi-hop networks have significantly facilitate our human life, securing and ensuring high quality services of these networks are still a primary concern. In particular, anomalous protocol operation in wireless multi-hop networks has recently received considerable attention in the research community. These relevant security issues are fundamentally different from those of wireline networks due to the special characteristics of wireless multi-hop networks, such as the limited energy resources and the lack of centralized control. These issues are extremely hard to cope with due to the absence of trust relationships between the nodes. To enhance security in wireless multi-hop networks, this dissertation addresses both MAC and routing layers misbehaviors issues, with main focuses on thwarting black hole attack in proactive routing protocols like OLSR, and greedy behavior in IEEE 802.11 MAC protocol. Our contributions are briefly summarized as follows. As for black hole attack, we analyze two types of attack scenarios: one is launched at routing layer, and the other is cross layer. We then provide comprehensive analysis on the consequences of this attack and propose effective countermeasures. As for MAC layer misbehavior, we particularly study the adaptive greedy behavior in the context of Wireless Mesh Networks (WMNs) and propose FLSAC (Fuzzy Logic based scheme to Struggle against Adaptive Cheaters) to cope with it. A new characterization of the greedy behavior in Mobile Ad Hoc Networks (MANETs) is also introduced. Finally, we design a new backoff scheme to quickly detect the greedy nodes that do not comply with IEEE 802.11 MAC protocol, together with a reaction scheme that encourages the greedy nodes to become honest rather than punishing them.
Download or read book Mobile and Wireless Networks written by Khaldoun Al Agha and published by John Wiley & Sons. This book was released on 2016-08-17 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the state of the art in the field of mobile and wireless networks, and anticipates the arrival of new standards and architectures. It focuses on wireless networks, starting with small personal area networks and progressing onto the very large cells of wireless regional area networks, via local area networks dominated by WiFi technology, and finally metropolitan networks. After a description of the existing 2G and 3G standards, with LTE being the latest release, LTE-A is addressed, which is the first 4G release, and a first indication of 5G is provided as seen through the standardizing bodies. 4G technology is described in detail along with the different LTE extensions related to the massive arrival of femtocells, the increase to a 1 Gbps capacity, and relay techniques. 5G is also discussed in order to show what can be expected in the near future. The Internet of Things is explained in a specific chapter due to its omnipresence in the literature, ad hoc and mesh networks form another important chapter as they have made a comeback after a long period of near hibernation, and the final chapter discusses a particularly recent topic: Mobile-Edge Computing (MEC) servers.
Download or read book Ad Hoc Networks Telecommunications and Game Theory written by Malek Benslama and published by John Wiley & Sons. This book was released on 2015-01-05 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Random SALOHA and CSMA protocols that are used to access MAC in ad hoc networks are very small compared to the multiple and spontaneous use of the transmission channel. So they have low immunity to the problems of packet collisions. Indeed, the transmission time is the critical factor in the operation of such networks. The simulations demonstrate the positive impact of erasure codes on the throughput of the transmission in ad hoc networks. However, the network still suffers from the intermittency and volatility of its efficiency throughout its operation, and it switches quickly to the saturation zone. In this context, game theory has demonstrated his ability to lead the network to a more efficient equilibrium. This, we were led to propose our model code set that formalizes the behavior of nodes during transmission within SALOHA networks and CSMA respectively.
