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Examines the issue of confidentiality of transmitted messages and of the devices themselves in ubiquitous computing. Analysis of asymmetric asymmetric cryptosystems; Comparison of maximum rate and maximum number of cycles; Distinction between secure disposal and encrypted storage.

Although the fascimile machine was invented in the 1840s, it remained largely a device used in the newspaper industry for the transmission of pictures until the mid-1980s. There were several reasons for this; some were technical and the others commercial. This chapter describes the fascimile machine as a system, as well as the design of its component parts. [ABSTRACT FROM PUBLISHER]

The article discusses about high-level synthesis. High-level synthesis (also known as behavioral synthesis) has been a popular research and development area since the 1970's. Several thousand papers on high-level synthesis have been published and more than a hundred prototype and production quality high level synthesis systems have been developed. The structure of computation is reorganized in such a way that input/output behavior is not altered. The goal is to make the computation more amenable for good implementation.

In this chapter we study multiconductor, multilayered transmission lines (MMTL) employing quasi-static, quasi-dynamic, and full-wave analyses. We begin with the quasi-static formulation (QSF), which provides the parasitic capacitance, inductance, resistance, and conductance. We introduce an intermediate formulation between that of the quasi-static and full-wave, referred to as the quasi-dynamic formulation (QDF). Next, we present the full-wave analysis, from which we extract the scattering parameters. The emphasis of this chapter is given to packaging and interconnects of high-speed digital circuits and systems and the implementation of numerical algorithms using wavelets. [ABSTRACT FROM PUBLISHER]

Any continuous-time analogue signal can be converted into a digital signal by making discrete both the time and the amplitude axes. The process of making the amplitude axis discrete is called quantization. It consists of dividing the amplitude axis in contiguous intervals and in associating to all the amplitudes within any interval a single amplitude value chosen among them. A regenerator receives the incoming pulse stream and transmits a new regenerated pulse stream that replicates the original sequence as closely as possible. To regenerate the signal, timing information must be known so that the regenerated pulse stream can be transmitted with the proper intervals between the pulses.

The SDH technique poses peculiar timing issues that deserve a closer look. Historically, the timing aspects of telecommunications networks have often been reduced to a set of pragmatic parameters and limits to verify, while their underlying rationale has not been normally considered part of the education of telecommunications engineers. Moreover, new timing issues have been raised by SDH, which implies new phenomena generating jitter and wander. In spite of the numerous advantages offered by SDH compared to PDH, SDH made the issue of controlling the jitter and wander of the transported tributaries more delicate than in traditional PDH networks.

Discusses the subject of ubiquitous computing. Formulation of ubiquitous computing at the Palo Alto Research Center of Xerox in California; Exploration of the vision of disappearing computing; Illustration of the concept of calm technology.

Introduces basic topics in computer security, particularly the three fundamental properties of confidentiality, integrity and availability in ubiquitous computing. Definition of disclosure as the threat to confidentiality; Analysis of encryption and decryption; Identification of the core idea of integrity protection.

Examines the issue of availability in ubiquitous computing. Investigation of threats to the communications channel; Identification of threats to the battery energy; Effect of the intersection of ubiquitous computing and mobile code.

Examines the issue of authentication in ubiquitous computing. Impact of the absence of an online server; Analysis of secure transient association; Discussion of the resurrecting duckling security policy model.

Examines the security solutions adopted in a variety of distributed systems, from the Internet to cellular telephony, and their replication in the ubiquitous computing context. Identification of Needham-Schroeder as one of the earliest and most influential authentication protocols for distributed systems; Mechanism of Kerberos, a network authentication protocol based on Needham-Schroeder; Method of managing and distributing public key infrastructures.

Focuses on the integrity of messages in ubiquitous computing. Prerequisites for integrity in a point-to-multipoint scenario; Protection of messages with a chain of hashes by the Guy Fawkes protocol; Mechanics of the scheme called Timed Efficient Stream Loss-tolerant Authentication.

Examines the issue of anonymity in ubiquitous computing. Development of the cocaine auction protocol as a way to conduct an anonymous auction in the absence of a trusted arbitrator; Investigation of the subtle trust issues in regular auctions; Analysis of the anonymity layer on which the auction protocol is built.

The views expressed in this chapter are those of the authors and do not necessarily reflect the views of their affiliation entity. [ABSTRACT FROM PUBLISHER]

Magnetic tapes and discs are the preferred media for the storage of electronic data where the data is to be retained even after the system power is switched off. A second medium commonly used for data storage is the flip-flop which can take one of two states (high or low corresponding to 1 or 0). In this case when the system power is shut off, the information stored is lost. Flip-flop circuits are discussed in detail in this appendix. Also discussed is semiconductor random access memory (RAM). [ABSTRACT FROM PUBLISHER]

The two basic functions of the radio receiver are: (1) to separate the signal induced in the antenna by the transmission that we wish to receive from all the other signals present and (2) to recover the "message" signal that was used to modulate the transmitter carrier. Basic and superheterodyne AM radio receivers are described in this chapter. [ABSTRACT FROM PUBLISHER]

The transmission of video images depends on a scanning device that can break up the image into a grid and measure the brightness of each element of the grid. This information can be sent serially or in parallel to a distant point and used to reproduce the image. It is evident that the smaller the size of the grid element, the better the definition of the image. The various aspects of television transmission are discussed in this chapter. [ABSTRACT FROM PUBLISHER]

Chapter 1 introduces the history of telecommunications. From the advent of the electric telegraph to the emergence of the Internet and the World Wide Web, the last 150 years have been a time of tremendous growth and change in telecommunications. [ABSTRACT FROM PUBLISHER]

It is on long-distance channels (trunks or tolls) that signal processing techniques have proven to be most successful. In this chapter the common signal processing techniques used in the telephone system and some of the circuits employed are examined. [ABSTRACT FROM PUBLISHER]

The article provides various information related to the book "Scheduling in Real-Time Systems." The information included covers the reserved rights of the publisher; contents of the book; description of the notations and symbols used in the articles included in the journal; and an introduction to the book. This book concerns applications where a computer system controls an environment in real-time. The primary objective of this book is to serve as a text book with exercises and answers, and also some useful case studies. The second objective of this book is to provide a reference book that can be used by practitioners and developers in the industry.

Chapter 6 models computer networks by a graph and the two-terminal and all-terminal reliability (availability) are developed in terms of event spaces and cut- and tie-sets. More advanced graph transformations are introduced. Exact and approximate solutions are discussed. Design of backbone networks using minimum cost and maximum reliability spanning trees and enhancement methods are developed. [ABSTRACT FROM PUBLISHER]

Chapter 3 analyzes and compares the reliability and availability of a wide range of redundant techniques, including parallel, standby, and r-out-or-n systems. Additional gains due to the addition of repair are analyzed. Markov models and Laplace transforms are used to simplify the analysis. The reliability of various RAID storage schemes is discussed and the levels of reliability and availability achieved in Tandem and Stratus non-stop system is studied. [ABSTRACT FROM PUBLISHER]

Chapter 4 studies the reliability and availability gains obtained for N-modular redundancy. Triple modular redundancy (TMR) is compared with 5-level modular redundancy. Voter circuits, redundant voters, imperfect voters, and comparisons with parallel and standby schemes are included. Markov models and Laplace transform solutions are used for repairable systems. Advanced voting techniques are introduced. [ABSTRACT FROM PUBLISHER]

Chapter 5 introduces software development and software engineering, and defines software errors. Reliability theory is reviewed and models for remaining number of software errors and software reliability are developed. Measurement of the model parameters and prediction of software reliability and mean time to failure (MTTF) are given for three different models. The chapter concludes with rollback and recovery techniques. [ABSTRACT FROM PUBLISHER]

Chapter 1 explores the need for fault-tolerance in modern systems, which are extremely complex because of the low cost and power provided by digital electronics. The growth in complexity is illustrated in Moore's law of microprocessor growth. Reliability and availability are defined and the values achieved in practice are compared for a number of highly reliable systems. [ABSTRACT FROM PUBLISHER]

The article focuses on the broad ranging topic of baseband processing. At present, the status of design tools and methods is emerging as the primary limitation in the development of efficient software defined radio (SDR) systems. Baseband technology has emerged as an important and central element of mature and generic SDR architectures. The baseband of any radio system is responsible for digitally transforming raw data streams into the correct format ready for transmission over a known wireless channel.

This chapter discusses the integration of performance engineering in the context of SDL (and MSC). The chapter represents an application of the general concepts and techniques introduced in chapter 2. We provide an in-depth discussion of the extra information to be associated with SDL to support performance engineering, and of the issues concerning the integration with SDL. In addition, we survey important tools that support performance engineering in the context of SDL and MSC. [ABSTRACT FROM PUBLISHER]

This article presents the introductory material for the journal "Systems Engineering With SDL." It provides a table of the contents, foreword, preface, acknowledgements and index of topics. In the foreword, the author writes that performance engineering means to describe, to analyze and to optimize the dynamic, time dependent behavior of systems. However, it is common for a system to be fully designed and functionally tested before an attempt is made to determine its performance characteristics. The redesign of software and hardware is costly and may cause late system delivery.

Chapter 10 focuses on the indoor system of BRAIN, a mm-waveband high-speed multimedia wireless LAN. It discusses the architecture and design of the prototype; a description of a wireless MAC protocol; the configuration and implementation of the system. [ABSTRACT FROM PUBLISHER]

Chapter 11 proposes a private branch exchange (PBX) based mobility manager for WLL, which allows users to receive wireless service at any location within the WLL service area. [ABSTRACT FROM PUBLISHER]

Chapter Six covers a channel model analysis based on a series of measurements carried out at 2GHz designed to characterize a wide band WLL in a range of environments; An experimental procedure used in two measurement campaigns; The data processing stages used to determine the channel parameters; The channel model used. [ABSTRACT FROM PUBLISHER]

The article presents information about the January 1, 2004 issue of the journal CDMA: Access and Switching. Code division may be considered as a generalized method for access and switching in communication networks. Such an approach may be viewed as a user encoding process where the choices of the code and spreading types can create a large set of access and switching techniques in which the traditional ones are included. In this sense, code division can provide a unified approach for multiple access and switching in communications.

This appendix provides detailed insight into the area of using CAD along the lines of the oscillator. It examines an electronic feedback system that dramatically improves the phase noise and a novel "push-push" oscillator, which has been proposed for various wireless applications. A complete introduction to nonlinear phase noise analysis of oscillators with validation is also included. [ABSTRACT FROM PUBLISHER]