71 research outputs found

    Secure mobile radio communication over narrowband RF channel.

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    by Wong Chun Kau, Jolly.Thesis (M.Phil.)--Chinese University of Hong Kong, 1992.Includes bibliographical references (leaves 84-88).ABSTRACT --- p.1ACKNOWLEDGEMENT --- p.3Chapter 1. --- INTRODUCTION --- p.7Chapter 1.1 --- Land Mobile Radio (LMR) CommunicationsChapter 1.2 --- Paramilitary Communications SecurityChapter 1.3 --- Voice Scrambling MethodsChapter 1.4 --- Digital Voice EncryptionChapter 1.5 --- Digital Secure LMRChapter 2. --- DESIGN GOALS --- p.20Chapter 2.1 --- System Concept and ConfigurationChapter 2.2 --- Operational RequirementsChapter 2.2.1 --- Operating conditionsChapter 2.2.2 --- Intelligibility and speech qualityChapter 2.2.3 --- Field coverage and transmission delayChapter 2.2.4 --- Reliability and maintenanceChapter 2.3 --- Functional RequirementsChapter 2.3.1 --- Major system featuresChapter 2.3.2 --- Cryptographic featuresChapter 2.3.3 --- Phone patch facilityChapter 2.3.4 --- Mobile data capabilityChapter 2.4 --- Bandwidth RequirementsChapter 2.5 --- Bit Error Rate RequirementsChapter 3. --- VOICE CODERS --- p.38Chapter 3.1 --- Digital Speech Coding MethodsChapter 3.1.1 --- Waveform codingChapter 3.1.2 --- Linear predictive codingChapter 3.1.3 --- Sub-band codingChapter 3.1.4 --- VocodersChapter 3.2 --- Performance EvaluationChapter 4. --- CRYPTOGRAPHIC CONCERNS --- p.52Chapter 4.1 --- Basic Concepts and CryptoanalysisChapter 4.2 --- Digital Encryption TechniquesChapter 4.3 --- Crypto SynchronizationChapter 4.3.1 --- Auto synchronizationChapter 4.3.2 --- Initial synchronizationChapter 4.3.3 --- Continuous synchronizationChapter 4.3.4 --- Hybrid synchronizationChapter 5. --- DIGITAL MODULATION --- p.63Chapter 5.1 --- Narrowband Channel RequirementsChapter 5.2 --- Narrowband Digital FMChapter 5.3 --- Performance EvaluationChapter 6. --- SYSTEM IMPLEMENTATION --- p.71Chapter 6.1 --- Potential EMC ProblemsChapter 6.2 --- Frequency PlanningChapter 6.3 --- Key ManagementChapter 6.4 --- Potential Electromagnetic Compatibility (EMC) ProblemsChapter 7. --- CONCLUSION --- p.80LIST OF ILLUSTRATIONS --- p.81REFERENCES --- p.82APPENDICES --- p.89Chapter I. --- Path Propagation Loss(L) Vs Distance (d)Chapter II. --- Speech Quality Assessment Tests performedby Special Duties Unit (SDU

    State-of-the-art Survey of Data Hiding in ECG Signal

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    With the development of new communication technologies, the number of biomedical data that is transmitted is constantly increasing. This is sensitive data and therefore it is very important to preserve privacy when transmitting it. For this purpose, techniques for data hiding in biomedical signals are used. This is a comprehensive survey of research papers that covers the latest techniques for data hiding in ECG signal and old techniques that are not covered by the latest surveys. We show an overview of the methodology, robustness, and imperceptibility of the techniques

    A study and some experimental work of digital image and video watermarking

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    The rapid growth of digitized media and the emergence of digital networks have created a pressing need for copyright protection and anonymous communications schemes. Digital watermarking (or data hiding in a more general term) is a kind of steganography technique by adding information into a digital data stream. Several most important watermarking schemes applied to multilevel and binary still images and digital videos were studied. They include schemes based on DCT (Discrete Cosine Transform), DWT (Discrete Wavelet Transform), and fractal transforms. The question whether these invisible watermarking techniques can resolve the issue of rightful ownership of intellectual properties was discussed. The watermarking schemes were further studied from malicious attack point of view, which is considered an effective way to advance the watermarking techniques. In particular, the StirMark robustness tests based on geometrical distortion were carried out. A binary watermarking scheme applied in the DCT domain is presented in this research project. The effect of the binarization procedure necessarily encountered in dealing with binary document images is found so strong that most of conventional embedding schemes fail in dealing with watermarking of binary document images. Some particular measures have to be taken. The initial simulation results indicate that the proposed technique is promising though further efforts need to be made

    Preserving data integrity of encoded medical images: the LAR compression framework

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    International audienceThrough the development of medical imaging systems and their integration into a complete information system, the need for advanced joint coding and network services becomes predominant. PACS (Picture Archiving and Communication System) aims to acquire, store and compress, retrieve, present and distribute medical images. These systems have to be accessible via the Internet or wireless channels. Thus protection processes against transmission errors have to be added to get a powerful joint source-channel coding tool. Moreover, these sensitive data require confidentiality and privacy for both archiving and transmission purposes, leading to use cryptography and data embedding solutions. This chapter introduces data integrity protection and developed dedicated tools of content protection and secure bitstream transmission for medical encoded image purposes. In particular, the LAR image coding method is defined together with advanced securization services

    Data Hiding and Its Applications

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    Data hiding techniques have been widely used to provide copyright protection, data integrity, covert communication, non-repudiation, and authentication, among other applications. In the context of the increased dissemination and distribution of multimedia content over the internet, data hiding methods, such as digital watermarking and steganography, are becoming increasingly relevant in providing multimedia security. The goal of this book is to focus on the improvement of data hiding algorithms and their different applications (both traditional and emerging), bringing together researchers and practitioners from different research fields, including data hiding, signal processing, cryptography, and information theory, among others

    High Capacity Analog Channels for Smart Documents

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    Widely-used valuable hardcopy documents such as passports, visas, driving licenses, educational certificates, entrance-passes for entertainment events etc. are conventionally protected against counterfeiting and data tampering attacks by applying analog security technologies (e.g. KINEGRAMS®, holograms, micro-printing, UV/IR inks etc.). How-ever, easy access to high quality, low price modern desktop publishing technology has left most of these technologies ineffective, giving rise to high quality false documents. The higher price and restricted usage are other drawbacks of the analog document pro-tection techniques. Digital watermarking and high capacity storage media such as IC-chips, optical data stripes etc. are the modern technologies being used in new machine-readable identity verification documents to ensure contents integrity; however, these technologies are either expensive or do not satisfy the application needs and demand to look for more efficient document protection technologies. In this research three different high capacity analog channels: high density data stripe (HD-DataStripe), data hiding in printed halftone images (watermarking), and super-posed constant background grayscale image (CBGI) are investigated for hidden com-munication along with their applications in smart documents. On way to develop high capacity analog channels, noise encountered from printing and scanning (PS) process is investigated with the objective to recover the digital information encoded at nearly maximum channel utilization. By utilizing noise behaviour, countermeasures against the noise are taken accordingly in data recovery process. HD-DataStripe is a printed binary image similar to the conventional 2-D barcodes (e.g. PDF417), but it offers much higher data storage capacity and is intended for machine-readable identity verification documents. The capacity offered by the HD-DataStripe is sufficient to store high quality biometric characteristics rather than extracted templates, in addition to the conventional bearer related data contained in a smart ID-card. It also eliminates the need for central database system (except for backup record) and other ex-pensive storage media, currently being used. While developing novel data-reading tech-nique for HD-DataStripe, to count for the unavoidable geometrical distortions, registra-tion marks pattern is chosen in such a way so that it results in accurate sampling points (a necessary condition for reliable data recovery at higher data encoding-rate). For more sophisticated distortions caused by the physical dot gain effects (intersymbol interfer-ence), the countermeasures such as application of sampling theorem, adaptive binariza-tion and post-data processing, each one of these providing only a necessary condition for reliable data recovery, are given. Finally, combining the various filters correspond-ing to these countermeasures, a novel Data-Reading technique for HD-DataStripe is given. The novel data-reading technique results in superior performance than the exist-ing techniques, intended for data recovery from printed media. In another scenario a small-size HD-DataStripe with maximum entropy is used as a copy detection pattern by utilizing information loss encountered at nearly maximum channel capacity. While considering the application of HD-DataStripe in hardcopy documents (contracts, official letters etc.), unlike existing work [Zha04], it allows one-to-one contents matching and does not depend on hash functions and OCR technology, constraints mainly imposed by the low data storage capacity offered by the existing analog media. For printed halftone images carrying hidden information higher capacity is mainly attributed to data-reading technique for HD-DataStripe that allows data recovery at higher printing resolution, a key requirement for a high quality watermarking technique in spatial domain. Digital halftoning and data encoding techniques are the other factors that contribute to data hiding technique given in this research. While considering security aspects, the new technique allows contents integrity and authenticity verification in the present scenario in which certain amount of errors are unavoidable, restricting the usage of existing techniques given for digital contents. Finally, a superposed constant background grayscale image, obtained by the repeated application of a specially designed small binary pattern, is used as channel for hidden communication and it allows up to 33 pages of A-4 size foreground text to be encoded in one CBGI. The higher capacity is contributed from data encoding symbols and data reading technique

    Refactoring of Security Antipatterns in Distributed Java Components

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    The importance of JAVA as a programming and execution environment has grown steadily over the past decade. Furthermore, the IT industry has adapted JAVA as a major building block for the creation of new middleware as well as a technology facilitating the migration of existing applications towards web-driven environments. Parallel in time, the role of security in distributed environments has gained attention, as a large amount of middleware applications has replaced enterprise-level mainframe systems. The protection of confidentiality, integrity and availability are therefore critical for the market success of a product. The vulnerability level of every product is determined by the weakest embedded component, and selling vulnerable products can cause enormous economic damage to software vendors. An important goal of this work is to create the awareness that the usage of a programming language, which is designed as being secure, is not sufficient to create secure and trustworthy distributed applications. Moreover, the incorporation of the threat model of the programming language improves the risk analysis by allowing a better definition of the attack surface of the application. The evolution of a programming language leads towards common patterns for solutions for recurring quality aspects. Suboptimal solutions, also known as ´antipatterns´, are typical causes for quality weaknesses such as security vulnerabilities. Moreover, the exposure to a specific environment is an important parameter for threat analysis, as code considered secure in a specific scenario can cause unexpected risks when switching the environment. Antipatterns are a well-established means on the abstractional level of system modeling to inform about the effects of incomplete solutions, which are also important in the later stages of the software development process. Especially on the implementation level, we see a deficit of helpful examples, that would give programmers a better and holistic understanding. In our basic assumption, we link the missing experience of programmers regarding the security properties of patterns within their code to the creation of software vulnerabilities. Traditional software development models focus on security properties only on the meta layer. To transfer these efficiently to the practical level, we provide a three-stage approach: First, we focus on typical security problems within JAVA applications, and develop a standardized catalogue of ´antipatterns´ with examples from standard software products. Detecting and avoiding these antipatterns positively influences software quality. We therefore focus, as second element of our methodology, on possible enhancements to common models for the software development process. These help to control and identify the occurrence of antipatterns during development activities, i. e. during the coding phase and during the phase of component assembly, integrating one´s own and third party code. Within the third part, and emphasizing the practical focus of this research, we implement prototypical tools for support of the software development phase. The practical findings of this research helped to enhance the security of the standard JAVA platforms and JEE frameworks. We verified the relevance of our methods and tools by applying these to standard software products leading to a measurable reduction of vulnerabilities and an information exchange with middleware vendors (Sun Microsystems, JBoss) targeting runtime security. Our goal is to enable software architects and software developers developing end-user applications to apply our findings with embedded standard components on their environments. From a high-level perspective, software architects profit from this work through the projection of the quality-of-service goals to protection details. This supports their task of deriving security requirements when selecting standard components. In order to give implementation-near practitioners a helpful starting point to benefit from our research we provide tools and case-studies to achieve security improvements within their own code base.Die Bedeutung der Programmiersprache JAVA als Baustein für Softwareentwicklungs- und Produktionsinfrastrukturen ist im letzten Jahrzehnt stetig gestiegen. JAVA hat sich als bedeutender Baustein für die Programmierung von Middleware-Lösungen etabliert. Ebenfalls evident ist die Verwendung von JAVA-Technologien zur Migration von existierenden Arbeitsplatz-Anwendungen hin zu webbasierten Einsatzszenarien. Parallel zu dieser Entwicklung hat sich die Rolle der IT-Sicherheit nicht zuletzt aufgrund der Verdrängung von mainframe-basierten Systemen hin zu verteilten Umgebungen verstärkt. Der Schutz von Vertraulichkeit, Integrität und Verfügbarkeit ist seit einigen Jahren ein kritisches Alleinstellungsmerkmal für den Markterfolg von Produkten. Verwundbarkeiten in Produkten wirken mittlerweile indirekt über kundenseitigen Vertrauensverlust negativ auf den wirtschaftlichen Erfolg der Softwarehersteller, zumal der Sicherheitsgrad eines Systems durch die verwundbarste Komponente bestimmt wird. Ein zentrales Ziel dieser Arbeit ist die Erkenntnis zu vermitteln, dass die alleinige Nutzung einer als ´sicher´ eingestuften Programmiersprache nicht als alleinige Grundlage zur Erstellung von sicheren und vertrauenswürdigen Anwendungen ausreicht. Vielmehr führt die Einbeziehung des Bedrohungsmodells der Programmiersprache zu einer verbesserten Risikobetrachtung, da die Angriffsfläche einer Anwendung detaillierter beschreibbar wird. Die Entwicklung und fortschreitende Akzeptanz einer Programmiersprache führt zu einer Verbreitung von allgemein anerkannten Lösungsmustern zur Erfüllung wiederkehrender Qualitätsanforderungen. Im Bereich der Dienstqualitäten fördern ´Gegenmuster´, d.h. nichtoptimale Lösungen, die Entstehung von Strukturschwächen, welche in der Domäne der IT-Sicherheit ´Verwundbarkeiten´ genannt werden. Des Weiteren ist die Einsatzumgebung einer Anwendung eine wichtige Kenngröße, um eine Bedrohungsanalyse durchzuführen, denn je nach Beschaffenheit der Bedrohungen im Zielszenario kann eine bestimmte Benutzeraktion eine Bedrohung darstellen, aber auch einen erwarteten Anwendungsfall charakterisieren. Während auf der Modellierungsebene ein breites Angebot von Beispielen zur Umsetzung von Sicherheitsmustern besteht, fehlt es den Programmierern auf der Implementierungsebene häufig an ganzheitlichem Verständnis. Dieses kann durch Beispiele, welche die Auswirkungen der Verwendung von ´Gegenmustern´ illustrieren, vermittelt werden. Unsere Kernannahme besteht darin, dass fehlende Erfahrung der Programmierer bzgl. der Sicherheitsrelevanz bei der Wahl von Implementierungsmustern zur Entstehung von Verwundbarkeiten führt. Bei der Vermittlung herkömmlicher Software-Entwicklungsmodelle wird die Integration von praktischen Ansätzen zur Umsetzung von Sicherheitsanforderungen zumeist nur in Meta-Modellen adressiert. Zur Erweiterung des Wirkungsgrades auf die praktische Ebene wird ein dreistufiger Ansatz präsentiert. Im ersten Teil stellen wir typische Sicherheitsprobleme von JAVA-Anwendungen in den Mittelpunkt der Betrachtung, und entwickeln einen standardisierten Katalog dieser ´Gegenmuster´. Die Relevanz der einzelnen Muster wird durch die Untersuchung des Auftretens dieser in Standardprodukten verifiziert. Der zweite Untersuchungsbereich widmet sich der Integration von Vorgehensweisen zur Identifikation und Vermeidung der ´Sicherheits-Gegenmuster´ innerhalb des Software-Entwicklungsprozesses. Hierfür werden zum einen Ansätze für die Analyse und Verbesserung von Implementierungsergebnissen zur Verfügung gestellt. Zum anderen wird, induziert durch die verbreitete Nutzung von Fremdkomponenten, die arbeitsintensive Auslieferungsphase mit einem Ansatz zur Erstellung ganzheitlicher Sicherheitsrichtlinien versorgt. Da bei dieser Arbeit die praktische Verwendbarkeit der Ergebnisse eine zentrale Anforderung darstellt, wird diese durch prototypische Werkzeuge und nachvollziehbare Beispiele in einer dritten Perspektive unterstützt. Die Relevanz der Anwendung der entwickelten Methoden und Werkzeuge auf Standardprodukte zeigt sich durch die im Laufe der Forschungsarbeit entdeckten Sicherheitsdefizite. Die Rückmeldung bei führenden Middleware-Herstellern (Sun Microsystems, JBoss) hat durch gegenseitigen Erfahrungsaustausch im Laufe dieser Forschungsarbeit zu einer messbaren Verringerung der Verwundbarkeit ihrer Middleware-Produkte geführt. Neben den erreichten positiven Auswirkungen bei den Herstellern der Basiskomponenten sollen Erfahrungen auch an die Architekten und Entwickler von Endprodukten, welche Standardkomponenten direkt oder indirekt nutzen, weitergereicht werden. Um auch dem praktisch interessierten Leser einen möglichst einfachen Einstieg zu bieten, stehen die Werkzeuge mit Hilfe von Fallstudien in einem praktischen Gesamtzusammenhang. Die für das Tiefenverständnis notwendigen Theoriebestandteile bieten dem Software-Architekten die Möglichkeit sicherheitsrelevante Auswirkungen einer Komponentenauswahl frühzeitig zu erkennen und bei der Systemgestaltung zu nutzen

    Big Data Security (Volume 3)

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    After a short description of the key concepts of big data the book explores on the secrecy and security threats posed especially by cloud based data storage. It delivers conceptual frameworks and models along with case studies of recent technology

    Intelligent Circuits and Systems

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    ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.  This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering
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