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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Feedback in wireless networks: cross-layer design, secrecy and reliability

Gopala, Praveen Kumar 19 September 2007 (has links)
No description available.
92

Le secret professionnel en droit marocain et en droit comparé / Professional secrecy under Moroccan law and comparative law

Tijani, Abdelmajid 30 April 2015 (has links)
Le secret professionnel est un concept qui a connu un succès sans précédant dans la plupart des pays à l’échelle internationale. Il s’est généralisé à toutes les professions et à tous les domaines, de telle sorte qu’il devient aujourd’hui un élément indispensable dans tous les secteurs d’activités. C’est pourquoi, le législateur lui réserve une place privilégiée dans l’arsenal juridique. Notre droit positif, en s’inspirant des législations des pays démocratiques, prévoit des règles spéciales applicables à l’obligation du secret professionnel. En effet, l’article 446 du code pénal marocain pose le principe général du secret professionnel. Il met à la charge des professionnels une obligation générale de ne pas révéler au grand public des secrets confiés par leurs clients. Cette obligation légale relève de l’ordre public à laquelle on ne peut y déroger.L'application de la règle générale du secret professionnel souffre toutefois d'exceptions dans les hypothèses expressément et limitativement définies par la loi ou expressément prévues par les parties dans leurs conventions. Ces dérogations sont généralement établies au profit d'administrations et d'autorités administratives et judiciaires, de collectivités, services et organismes publics. En dehors de ces cas limitativement prévus par la loi qui autorisent larévélation par le professionnel du secret de nature professionnelle, il existe d’autres hypothèses de la levée de tels secrets, sans pour autant engager la responsabilité du confident. Il en ira ainsi, de l’infraction du blanchiment d’argent et le domaine des nouvelles technologies d’information et de communication, communément appelé le domaine duNumérique. La violation du secret professionnel par un agent de l'Administration entraîne l'application de sanctions pénales et, le cas échéant, de sanctions civiles, sans préjudice des sanctions disciplinaires pour manquement à la discrétion professionnelle. / Professional secrecy is a concept that has known unprecedented success in most countries worldwide. It has been generalized to all professions and areas such that it has become an indispensable tool for all sectors. For this reason, the legislature has placed professional secrecy on a privileged level of the legal arsenal. Our Positive Law, drawing on the laws of democratic countries, lays down special rules applicable to the obligation of professional secrecy. Indeed, Article 446 of the Moroccan Penal Code establishes the general principle of confidentiality. It imposes on professionals a general obligation not to disclose customers’ secrets to the public. This legal obligation relates to public order; from which we cannot derogate. The implementation of the general rule of professional secrecy allows exceptions in certain cases expressly and restrictively defined by law or expressly provided by parties in their agreements. These obligations are generally drawn up for administrations, administrative and judiciary authorities, communities, government departments and agencies. Apart from these legally prescribed and limited cases which authorize disclosure of professional secrets, thereexist other instances which permit the lifting of such secrets, without, however, engaging the liability of the confidant.This could be applicable to the infraction of money laundering and to the field of new information and communication technologies, commonly called the Digital Domain. The violation of professional secrecy by an agent of the Administration entails the execution of penal sanctions and, eventually, civil penalties, without prejudice to disciplinary sanctions forviolating professional secrecy.
93

From qualitative to quantitative program analysis : permissive enforcement of secure information flow / Approches qualitatives et quantitatives d'analyse de programmes : mise en oeuvre permissive de flux d’information sécurisés

Assaf, Mounir 06 May 2015 (has links)
De nos jours, les ordinateurs sont omniprésents. Tous ces ordinateurs stockent et manipulent de l'information, parfois sensible, d'où l'intérêt de protéger et de confiner la dissémination de cette information. Les mécanismes de contrôle de flux d'information permettent justement d'analyser des programmes manipulant de l'information sensible, afin de prévenir les fuites d'information. Les contributions de cette thèse incluent des techniques d'analyse de programmes pour le contrôle de flux d'information tant qualitatif que quantitatif. Les techniques d'analyse qualitatives permettent la détection et la prévention des fuites d'information. Les techniques quantitatives permettent d'estimer ces fuites afin de décider si elles sont négligeables. / Computers have become widespread nowadays. All these computers store and process information. Often, some of this information is sensitive; hence the need to confine and control its dissemination. An important field in computer science, that is concerned about analysing programs in order to confine and control the release of sensitive information, is the information flow control field. The contributions of this thesis include program analysis techniques for qualitative and quantitative information flow control. Qualitative techniques aim at detecting and preventing information leaks. Quantitative techniques go beyong the detection of information leaks, by estimating the leakage in order to decide whether it is negligeable.
94

Design and Analysis of QoS-Aware Key Management and Intrusion Detection Protocols for Secure Mobile Group Communications in Wireless Networks

Cho, Jin-Hee 10 December 2008 (has links)
Many mobile applications in wireless networks such as military battlefield, emergency response, and mobile commerce are based on the notion of secure group communications. Unlike traditional security protocols which concern security properties only, in this dissertation research we design and analyze a class of QoS-aware protocols for secure group communications in wireless networks with the goal to satisfy not only security requirements in terms of secrecy, confidentiality, authentication, availability and data integrity, but also performance requirements in terms of latency, network traffic, response time, scalability and reconfigurability. We consider two elements in the dissertation research: design and analysis. The dissertation research has three major contributions. First, we develop three "threshold-based" periodic batch rekeying protocols to reduce the network communication cost caused by rekeying operations to deal with outsider attacks. Instead of individual rekeying, i.e., performing a rekeying operation right after each group membership change event, these protocols perform batch rekeying periodically. We demonstrate that an optimal rekey interval exists that would satisfy an imposed security requirement while minimizing the network communication cost. Second, we propose and analyze QoS-aware intrusion detection protocols for secure group communications in mobile ad hoc networks to deal with insider attacks. We consider a class of intrusion detection protocols including host-based and voting-based protocols for detecting and evicting compromised nodes and examine their effect on the mean time to security failure metric versus the response time metric. Our analysis reveals that there exists an optimal intrusion detection interval under which the system lifetime metric can be best traded off for the response time performance metric, or vice versa. Furthermore, the intrusion detection interval can be dynamically adjusted based on the attacker behaviors to maximize the system lifetime while satisfying a system-imposed response time or network traffic requirement. Third, we propose and analyze a scalable and efficient region-based group key management protocol for managing mobile groups in mobile ad hoc networks. We take a region-based approach by which group members are broken into region-based subgroups, and leaders in subgroups securely communicate with each other to agree on a group key in response to membership change and member mobility events. We identify the optimal regional area size that minimizes the network communication cost while satisfying the application security requirements, allowing mobile groups to react to network partition/merge events for dynamic reconfigurability and survivability. We further investigate the effect of integrating QoS-aware intrusion detection with region-based group key management and identify combined optimal settings in terms of the optimal regional size and the optimal intrusion detection interval under which the security and performance properties of the system can be best optimized. We evaluate the merits of our proposed QoS-aware security protocols for mobile group communications through model-based mathematical analyses with extensive simulation validation. We perform thorough comparative analyses against baseline secure group communication protocols which do not consider security versus performance tradeoffs, including those based on individual rekeying, no intrusion detection, and/or no-region designs. The results obtained show that our proposed QoS-aware security protocols outperform these baseline algorithms. â / Ph. D.
95

Obfuscation of Transmission Fingerprints for Secure Wireless Communications

Rahbari, Hanif January 2016 (has links)
Our world of people and objects is on the verge of transforming to a world of highly-interconnected wireless devices. Incredible advances in wireless communications, hardware design, and power storage have facilitated hasty spread of wireless technologies in human life. In this new world, individuals are often identified and reached via one or multiple wireless devices that they always carry (e.g., smartphones, smart wearable, implantable medical devices, etc.), and their biometrics identities are replaced by their digital fingerprints. In near future, vehicles will be controlled and monitored via wireless monitoring systems and various physical objects (e.g., home appliance and retail store items) will be connected to the Internet. The list of these changes goes on. Unfortunately, as different aspects of our lives are being immerged in and dependent to wireless devices and services, we will become more vulnerable to wireless service/connection interruptions due to adversarial behavior and our privacy will become more potent to be exposed to adversaries. An adversary can learn the procedures of a wireless system and analyze its stages, and accordingly, launch various attacks against the operations of the system or the privacy of the people. Existing data confidentiality and integrity services (e.g., advanced encryption algorithms) have been able to prevent the leakage of users' messages. However, in wireless networks, even when upper-layer payloads are encrypted, the users' privacy and the operation of a wireless network can be threatened by the leakage of transmission attributes at the physical (PHY) layer. Examples of these attributes are payload size, frequency offset (FO), modulation scheme, and the transmission rate. These attributes can be exploited by an adversary to launch passive or active attacks. A passive attacker may learn about the interests, sexual orientation, political views, and patentable ideas of the user through analyzing these features, whereas an active attacker exploits captured attributes to launch selective packet jamming/dropping and disrupt wireless services. These call for novel privacy preserving techniques beyond encryption. In this dissertation, we study the vulnerability of current wireless systems to the leakage of transmission attributes at the PHY layer and propose several schemes to prevent it. First, we design and experimentally demonstrate with USRPs an energy-efficient and highly disruptive jamming attack on the FO estimation of an OFDM system. OFDM is the core multiplexing scheme in many modern wireless systems (e.g., LTE/5G and 802.11a/n/ac) and is highly susceptible to FO. FO is the difference in the operating frequencies of two radio oscillators. This estimation is done by the receiver using the publicly-known frame preamble. We show that the leakage of FO value via the preamble can facilitate an optimally designed jamming signal without needing to know the channel between the transmitter and the legitimate receiver. Our results show that the jammer can guarantee a successful attack even when its power is slightly less than the transmitter's power. We then propose four mitigation approaches against the proposed FO attack. Next, we consider certain transmission attributes that are disclosed via unencrypted PHY/MAC headers. Example of these attributes are payload size, transmission rate, and MAC addresses. Beyond unencrypted headers, the adversary can estimate the frame size and transmission rate through identifying the payload's modulation scheme and measuring the transmission time. To prevent the leakage of these attributes, we propose Friendly CryptoJam scheme, which consists of three components: First, a modulation-aware encryption scheme to encrypt the headers. Second, an efficient modulation obfuscation techniques. Specifically, the proposed modulation obfuscation scheme embeds the modulation symbols of a frame's payload into the constellation of the highest-order modulation scheme supported by the system. Together with effective PHY/MAC header encryption at the modulation level, the proposed obfuscation scheme hides the transmission rate, payload size, and other attributes announced in the headers while avoiding any BER performance loss. Compared with prior art, Friendly CryptoJam enjoys less complexity and less susceptibility to FO estimation errors. The third component is a novel PHY-level identification method. To facilitate PHY/MAC header encryption when a MAC layer sender identifier cannot be used (e.g., due to MAC address encryption), we propose two preamble-based sender identification methods, one for OFDM and one for non-OFDM systems. A sender identifier is special message that can be embedded in the frame preamble. The extent of the applications of our embedding scheme goes beyond identifier embedding and include embedding part of the data frame, the sender's digital signature, or any meta-data that the sender provides. Our message embedding method can further be used to mitigate the FO estimation attack because the jammer can no longer optimize its jamming signal with respect to a fixed preamble signal. In addition, we considered friendly jamming technique in a multi-link/hop network to degrade the channels of the eavesdroppers and prevent successful decoding of the headers, while minimizing the required jamming power by optimally placing the friendly jamming devices.
96

Physical-Layer Security in Orbital Angular Momentum Multiplexing Free-Space Optical Communications

Sun, Xiaole, Djordjevic, Ivan B. 02 1900 (has links)
The physical-layer security of a line-of-sight (LOS) free-space optical (FSO) link using orbital angular momentum (OAM) multiplexing is studied. We discuss the effect of atmospheric turbulence to OAM-multiplexed FSO channels. We numerically simulate the propagation of OAM-multiplexed beam and study the secrecy capacity. We show that, under certain conditions, the OAM multiplexing technique provides higher security over a single-mode transmission channel in terms of the total secrecy capacity and the probability of achieving a secure communication. We also study the power cost effect at the transmitter side for both fixed system power and equal channel power scenarios.
97

Detente or Razryadka? The Kissinger-Dobrynin Telephone Transcripts and Relaxing American-Soviet Tensions, 1969-1977.

Stackhouse, Daniel S., Jr. 01 January 2013 (has links)
This dissertation argues that through a secret backchannel, US National Security Adviser and later Secretary of State Henry Kissinger and Soviet Ambassador to the US Anatoly Dobrynin formed a relationship which provided the empathy needed to bridge many of the ideological differences between their two countries. It examines transcripts of their telephone conversations from 1969-1977 when the United States and the Soviet Union engaged in detente, or a relaxation of tensions, during the Cold War. The dissertation concludes that the Kissinger-Dobrynin backchannel serves as a case study of the effectiveness of back channels in international diplomacy.
98

The Financial Secrecy Index: An Information Theory Approach / The Financial Secrecy Index: An Information Theory Approach

Galuszka, Lukáš January 2016 (has links)
The objective of this thesis is to evaluate alternative weighting systems to determine if they have the potential to improve the current weighting system of the Financial Secrecy Index (FSI). The FSI, a measure of countries' contributions to global financial secrecy, currently weights its 15 qualitative components equally. A web-based opinion survey conducted in January and February 2016 among academics, journalists, experts and other persons familiar with FSI serves as the baseline for assessing new weights. The new weights derived from the survey results are not significantly different from the equal weights in 14 out of 15 components. The survey results suggest that widely held opinion is consistent with equal weight assumptions. Statistical model selection criteria from information theory that penalize model complexity prefer in majority of cases the simple model over the more complex one even though more complex model provides better goodness-of-fit statistics. Alternative methods and analysis such as Principal Components Analysis is performed and discussed. The present work finds that, statistically, the weights should not diverge from the equal weighting system in use currently. Powered by TCPDF (www.tcpdf.org)
99

Administrative secrecy: the uses and abuses of information in the security classification system

Sturmer, Ronald T., Sturmer, Ronald T. January 1979 (has links)
No description available.
100

O sigilo bancário brasileiro face à nova regulamentação americana Foreign Account Tax Compliance Act - FATCA

Holzmann, Deia Virginia Tidei 10 March 2016 (has links)
Made available in DSpace on 2016-04-26T20:24:22Z (GMT). No. of bitstreams: 1 Deia Virginia Tidei Holzmann.pdf: 908027 bytes, checksum: 7c5dac144c97c3c30b6f9d918e675b21 (MD5) Previous issue date: 2016-03-10 / In light of the globalization we are facing a new reality of global interconnections which act as a central power transforming the international judicial relationships. Some countries have enacted regulations with extraterritorial effects as the Foreign Account Tax Compliance Act (FATCA), which establishes the sharing of information protected by bank secrecy which constitutes fundamental rights pursuant to the terms of the Brazilian Constitution. The proposal of the present work is to conduct an analysis of the Brazilian judicial system vis a vis the obligations established by the Foreign Account Tax Compliance Act (FATCA) in order to explore possible conflicts between the American regulation and the Brazilian laws with emphasis in the review of the fundamental rights guaranteed by the Brazilian Constitution. In the present work the topics covered are related to the historic and conceptual evolution of the bank secrecy and its insertion in the Brazilian law, the concept of the Foreign Account Tax Compliance Act (FATCA) and brief analysis of the Intergovernmental Cooperation Agreement (IGA) executed between Brazil and the United States of America, considerations on individual rights and guarantees protected by the Brazilian regulation and conclusion about the treatment of bank secrecy in Brazil / Em face da globalização nos vemos diante de uma nova realidade de interconexões globais que atuam como força motriz transformadora das relações jurídicas internacionais. Alguns países têm promulgado regulamentações com alcance extraterritorial, como no caso do Foreign Account Tax Compliance Act (FATCA), que determina o compartilhamento de informações protegidas por sigilo bancário que constituem direito fundamental nos termos da Constituição Federal brasileira de 1988. A proposta do presente trabalho é realizar uma análise do sistema jurídico brasileiro vis-à-vis as obrigações estabelecidas pelo Foreign Account Tax Compliance Act (FATCA) de forma a abordar possíveis confrontos entre esta regulamentação americana e as leis brasileiras, com ênfase na análise dos direitos fundamentais assegurados pela Constituição Federal de 1988. Na presente dissertação são abordados temas referentes a evolução histórica e conceitual do sigilo bancário e sua inserção no direito brasileiro, conceituação jurídica do Foreign Account Tax Compliance Act (FATCA) e breve análise do Acordo de Cooperação Intergovernamental (IGA) firmado entre o Brasil e os Estados Unidos da América, considerações acerca os direitos e garantias individuais tutelados pela regulamentação brasileira e conclusão acerca do tratamento do sigilo bancário no Brasil

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