7UDGLWLRQDOO\ 4R6 KDV EHHQ DGGUHVVHG E\ XVLQJ network measurements (e.g., loss rates and delays), and little attention has been paid to the quality perceived by end-users of the applications running over the network. Here, we address the issue of integrating speech quality subjective scores and network parameters measurements, for designing control algorithms that would yield the best QoS that could be delivered under a given communications network situation. First, we build a neural network based automaton to measure speech quality in real time, at the style of a group of human subjects when participating in an MOS test. We consider the effects of changes in network parameters (e.g., packetization interval, packet loss rate and their pattern distribution) and encoding on speech signals transmitted over the network. Our database includes transmitted speech signals in different languages. Then, we outline a control mechanism which, based on the application performance within a session (i.e., MOS speech quality scores generated by the neural networks), dynamically adjusts parameters (codec and packetization interval). Finally, we analyze preliminary results to show two main benefits: first, a better use of bandwidth, and second, delivery of the best possible speech quality given the network current situation. Index Terms9RLFH RYHU ,3 3DFNHW 6ZLWFKHG 1HWZRUNV Speech Quality Assessment, Neural Networks and End-to-End Control Mechanisms.

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<p class="MsoNormal" style="text-align: left; margin: 0cm 0cm 0pt;" align="left"><span class="text"><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;">RFID (Radio frequency identification) technology raises many privacy concerns among which the potential tracking of an RFID tag bearer and the eventuality of an illegitimate reading device (reader) collecting information about him. To solve these issues, many RFID privacy protecting protocols assume that readers have continuous connectivity with a centralised on-line database in charge of the identification of a certain amount of tags. However such centralised models can raise scalability and latency problems. Moreover, they are not suitable in applications where connectivity is intermittent. As RFID tags may often change hands, it is also necessary to guarantee the privacy of a new tag owner. In this paper, we introduce a privacy protecting scheme based on pseudonyms that allows an online database to delegate temporarily and in a secure manner the capability to identify tags to selected readers. A reader which receives delegation for a given tag can identify this tag without referring to the on-line database, thus solving possible intermittent connectivity issues and making tag identification more scalable. Our protocol also manages tags ownership transfer without threatening the new owner’s privacy.</span></span><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;"></span></p>

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All Rights ReservedNo part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. © 2007 Springer ISBN 978-1-4020-5396-2 (HB) ISBN 978-1-4020-5397-9 (e-book) I dedicate this book to my husband, my parents and my sister and brothers Houda Laboid Contents Dedication v Preface xiii Foreword xv Glossary 293References 311 PrefaceThe advent of ubiquitous computing and the proliferation of portable computing devices have raised the importance of mobile and wireless networking. Recently, there has been a tremendous interest in broadband wireless access systems, including wireless local area networks (WLANs), broadband wireless access, and wireless personal area networks (WPANs). This domain is a subject of huge research and many standardization activities are undertaken throughout the world.Based on the most recent developments in the field of wireless technologies related to WLAN, WPAN, wireless sensor networks (WSN) and wireless metropolitan area network (WMAN), this book gives a detailed description of the widespread or recently used standards like Wi-Fi, Bluetooth, ZigBee, and WiMAX. Our book aims at regrouping in a single volume up-to-date information related to these different technologies, which can be used separately or combined to provide specific applications. The emergence of these very promising systems is mainly due to great technological progress in the field of wireless communication protocols; they will also make it possible to offer a broad range of new applications in both civilian and military domains. The inherent characteristics of these systems imply new challenges. Our book deals with several relevant topics related to the evolution of these spontaneous, selforganized, or cellular-based networks. Through its seven chapters, we tackle critical problems such as the design of medium access control (MAC) and routing protocols, the support of the quality of service, the security mechanisms, the mobility/roaming aspects, etc. We preferred to follow an analysis-oriented approach which aims at drawing up complete states of the art on both technology and standards. We also present some practical aspects and highlight some trends as a stake for future standards. This book is intended for readers with knowledge of networking and protocols. The audience includes network engineers, designers, implementers, undergraduate/graduate/postgraduate students, and information systems managers.The standards that we present are definitely based strongly on the knowledge of modulation and coding though we try, in this book, to pass over this domain which is widely tackled in many specialized books. Hence, we try to xiii xiv Preface attract readers who are new to these technologies a...