Global ETD Search

231	Enhancing Security, Privacy, and Efficiency of Vehicular Networks Al-Shareeda, Sarah Yaseen Abdulrazzaq 07 December 2017 (has links) No description available. Computer Engineering Computer Science Electrical Engineering Transportation Vehicular Networks Public Key Infrastructure Security Privacy Cryptography Elliptic Curves Cryptography Pairings Group Signatures Trust Authentication Grouping Dedicated Short Range Communication Beaconing Rate
232	Elektroninio parašo atributų sertifikavimas / Certification of electronic signature attributes Lozda, Marius 27 June 2014 (has links) Darbe nagrinėjama atributinės informacijos sertifikavimo šiuo metu naudojamuose elektroniniuse parašuose problema. Trumpai apžvelgiami elektroninio parašo principai ir supažindinama su viešųjų raktų infrastruktūra, nurodant galimybes jai išplėsti, iškilus poreikiui užtikrinti aukštesnį saugumo lygį keičiantis papildoma (atributine) informacija. Nagrinėjami įvairūs atributinės informacijos sertifikavimo metodai, viešųjų raktų infrastruktūroje įvedant atributų sertifikato ir atributų sertifikavimo centro sąvokas. Pateikiamas tinkamiausio metodo pritaikymo pavyzdys, modeliuojant elektroninio parašo naudojimo situaciją, artimą dabartinei situacijai Lietuvoje. Sprendimo pritaikymas demonstruojamas apibrėžiant patobulintos elektroninio parašo infrastruktūros prototipą. / This paper analyses issues of attribute certification in currently used electronic signatures. Fundamentals of electronic signatures and public key infrastructure are briefly described, focusing on possibilities of achieving higher security level in communication when attribute information is important. Various suggestions for attribute certification are analysed, introducing atribute certificates and atribute authorities. Different certification methods are compared and evaluated, applying the most suitable one in the public key infrastructure usage model, that is constructed by simplifying the current situation of electronic signatures. The solution is represented by describing the prototype of improved electronic signature infrastructure. Atributų sertifikavimas Autorizacija Autentifikacija Atributinė informacija Elektroninis parašas Sertifikatas Sertifikavimo centras X.509 Parašo taisyklės Prototipas Skaitmeninis parašas Viešųjų raktų infrastruktūra Sertifikavimo veiklos nuostatai Attribute certification Authorization Autentification Digital signature Electronic signature Certificate Certificate authority Signature policy Prototipe Public key infrastructure Certificate practice statement
233	Inter-device authentication protocol for the Internet of Things Wilson, Preethy 18 May 2017 (has links) The Internet of things (IoT) recently blossomed remarkably and has been transforming the everyday physical entities around us into an ecosystem of information that will enrich our lives in unimaginable ways. Authentication is one of the primary goals of security in the IoT and acts as the main gateway to a secure system which transmits confidential and/or private data.This thesis focuses on a Device-to-Device Mutual Authentication Protocol, designed for the smart home network, which is an essential component of communication in the Internet of Things(IoT). The protocol has been developed based on asymmetric cryptography to authenticate the devices in the network and for the devices to agree on a shared secret session key. In order to ensure the security of a communications session between the devices, the session keys are changed frequently - ideally after every communication session. The proposed scheme has been programmed in HLPSL, simulated and its efficiency verified using the SPAN/ AVISPA tool. When SPAN substantiates the protocol simulation and the attacker simulation, the back-ends of the AVISPA tool verifies the safety and security of the proposed authentication protocol. The thesis also evaluates the protocol's security against the attacks successful against protocols proposed by other researchers. / Graduate / 0544 / 0984 / 0537 / pwilson1@uvic.ca Authentication Internet of Things (IoT) Smart Homes Smart Home Network AVISPA/SPAN AVISPA Internet Security Cryptography Encryption Asymmetric Cryptography Shared Session Key Private Key Public Key Cloud Fog Security HLPSL Quality Metrics Simulation Protocol Simulation Attacker Simulation Formal Verification Verification Multi-protocol Attack Reflection Attack OFMC CL-AtSe Communication Computing Mutual Authentication Device-to-device inter-device machine-to-machine Attacks
234	Criptografia de chave pública sem certificado / Certificateless public key cryptography Goya, Denise Hideko 16 December 2011 (has links) A criptografia de chave pública sem certificado (certificateless) é uma alternativa ao modelo convencional de criptografia assimétrica, pois a autenticação da chave pública ocorre implicitamente durante a execução dos protocolos, sem a necessidade de gerenciamento e distribuição de certificados digitais. Potencialmente reduz custos computacionais e o nível de segurança alcançado é maior quando comparado ao modelo baseado em identidade. Nesta tese de doutorado, modelos formais de segurança para acordo de chave com autenticação sem certificado são aprimorados visando dois objetivos paralelos: (1) aumentar o nível de confiança que usuários podem depositar na autoridade geradora de chaves secretas parciais e (2) viabilizar protocolos que sejam eficientes computacionalmente e com propriedades de segurança relevantes, dentre as quais se inclui resistência a ataques de adversários que têm total controle do canal de comunicação e que podem substituir chaves públicas de usuários por valores arbitrários. Para atestar que as melhorias efetuadas são praticáveis e possibilitam que os objetivos sejam alcançados, novos protocolos são propostos para o caso que envolve dois participantes na comunicação. Os protocolos são provados seguros, usando-se técnica de redução de problemas computacionais. / Certificateless public key cryptography is an alternative model to traditional asymmetric key cryptography, because the public key authentication occurs implicitly during a protocol run, with no need of digital certificates management and distribution. It has the potential to reduce computing costs, and it allows a higher security level than the one in the identity-based model. In this PhD thesis, formal security models for certificateless authenticated key agreement are improved with two independent objectives: (1) to increase the trust level for the partial secret key generating authority on which users rely, and (2) to enable computationally efficient protocols, with significant security properties, such as resistance against attacks from adversaries with full control of the communication channel, and from adversaries who are able to replace users\' public keys by any chosen value. In order to demonstrate that these improvements made are feasible and achieve the objectives, new protocols are proposed in the two-party case. These protocols are proved secure by using reduction techniques for provable security. Acordo de chave com autenticação Authenticated key agreement Bilinear pairing Certificateless public key cryptography Criptografia sobre curva elíptica Elliptic curve cryptography Emparelhamento bilinear Information systems security Modelos de segurança Provable security Security models Segurança de sistemas de informação Segurança demonstrável
235	A Bio-Inspired Autonomous Authentication Mechanism in Mobile Ad Hoc Networks / Ein bioinspirierter autonomer Authentifizierungsmechanismus in mobilen Ad-hoc-Netzwerken Memarmoshrefi, Parisa 30 May 2012 (has links) No description available. 004 Informatik AHH 430 AHI 000 Mathematics and Computer Science mobiles ad hoc Netzwerk (MANET) Soft Sicherheitsmechanismus autonomes System Ameisenkolonien Optimierung (ACO) Mobile ad hoc network (MANET) Soft security mechanism Public key authentication autonomous system Ant colony optimization (ACO) 54.00
236	Det rättsliga utrymmet för implementering av elektroniska underskrifter vid uppfyllandet av formkrav : En studie av formkraven / The legal capacity for implementation of electronic signatures when fulfilling forms prescribed by law : A study of the forms prescribed by law Christerson, Johan, Kihlstrand, Jakob January 2018 (has links) Elektroniska underskrifter är en relativt ny metod för att ingå bindande avtal. Tanken med tekniken är att den ska effektivisera, förenkla och öka säkerheten för användarna vid ingående av avtal. Det kan dock uppstå problem när lagstiftning anpassas till att reglera ny teknik, eftersom det är viktigt att lagstiftaren fortsätter att ta hänsyn till de skyddsintressen som ligger bakom gällande rätt. Denna uppsats belyser och diskuterar rättsliga hinder som föreligger vid användandet av elektroniska underskrifter, vid upprättande av de tre, privaträttsligt mest vanliga, rättshandlingarna som kräver en viss form för giltighet: överlåtelse av fast egendom, upprättande av testamente eller äktenskapsförord. Uppsatsen utreder hur den nya EU-förordningen eIDAS ((EU) nr 910/2014) har påverkat svenska myndigheters förhållningssätt till elektroniska underskrifter och elektroniska handlingar. Från presumtionen att det var fysiska handlingar som krävdes, om inte särskilda regler godkände elektroniska rutiner, till att elektroniska rutiner gäller om inte särskilda formkrav förbjuder det. Vidare förklaras förenklat tekniken bakom avancerade- och kvalificerade signaturer samt elektroniska dokument. Formkraven för skriftlighet, underskrift, bevittning och registrering och de skyddsintressen som ligger bakom dessa analyseras. Formkraven till ovan nämnda rättshandlingar kan till viss del tillgodoses med elektroniska signaturer och dokument, men i dagsläget krävs det en fysisk underskrift för att göra ovan nämnda rättshandlingar giltiga, på grund av den tolkning av begreppet underskrift som har gjorts i Ds 2003:29. Vidare analyseras hur sakrätten, rent teoretiskt, skulle kunna förändras genom en potentiell lagändring eller om en ny tolkning av begreppet underskrift medför att elektroniska signaturer kan användas vid överlåtelse av fast egendom. I uppsatsen diskuteras även de förtjänster och risker som en lagändring skulle kunna innebära, och hur dessa bör vägas mot varandra, för att sedan konstatera om en ökad implementering av elektroniska rutiner är önskvärd eller inte. Public-key Juridik Elektronisk underskrift Avtal överlåtelse av fast egendom upprättande av testamente upprättande av äktenskapsförord eIDAS elektroniska handlingar avancerade signaturer kvalificerade signaturer Formkrav Underskrift BankID Biometri jordabalken formfel köpehandling bindande rättshandlingar e-legitimation digital signatur elektroniskt certifikat Mobilt BankID Avtalsrätt Law Juridik
237	Implantation sécurisée de protocoles cryptographiques basés sur les codes correcteurs d'erreurs / Secure implementation of cryptographic protocols based on error-correcting codes Richmond, Tania 24 October 2016 (has links) Le premier protocole cryptographique basé sur les codes correcteurs d'erreurs a été proposé en 1978 par Robert McEliece. La cryptographie basée sur les codes est dite post-quantique car il n'existe pas à l'heure actuelle d'algorithme capable d'attaquer ce type de protocoles en temps polynomial, même en utilisant un ordinateur quantique, contrairement aux protocoles basés sur des problèmes de théorie des nombres. Toutefois, la sécurité du cryptosystème de McEliece ne repose pas uniquement sur des problèmes mathématiques. L'implantation, logicielle ou matérielle, a également un rôle très important pour sa sécurité et l'étude de celle-ci face aux attaques par canaux auxiliaires/cachés n'a débuté qu'en 2008. Des améliorations sont encore possibles. Dans cette thèse, nous proposons de nouvelles attaques sur le déchiffrement du cryptosystème de McEliece, utilisé avec les codes de Goppa classiques, ainsi que des contre-mesures correspondantes. Les attaques proposées sont des analyses de temps d'exécution ou de consommation d'énergie. Les contre-mesures associées reposent sur des propriétés mathématiques et algorithmiques. Nous montrons qu'il est essentiel de sécuriser l'algorithme de déchiffrement en le considérant dans son ensemble et non pas seulement étape par étape / The first cryptographic protocol based on error-correcting codes was proposed in 1978 by Robert McEliece. Cryptography based on codes is called post-quantum because until now, no algorithm able to attack this kind of protocols in polynomial time, even using a quantum computer, has been proposed. This is in contrast with protocols based on number theory problems like factorization of large numbers, for which efficient Shor's algorithm can be used on quantum computers. Nevertheless, the McEliece cryptosystem security is based not only on mathematical problems. Implementation (in software or hardware) is also very important for its security. Study of side-channel attacks against the McEliece cryptosystem have begun in 2008. Improvements can still be done. In this thesis, we propose new attacks against decryption in the McEliece cryptosystem, used with classical Goppa codes, including corresponding countermeasures. Proposed attacks are based on evaluation of execution time of the algorithm or its power consumption analysis. Associate countermeasures are based on mathematical and algorithmic properties of the underlying algorithm. We show that it is necessary to secure the decryption algorithm by considering it as a whole and not only step by step Cryptographie à clé publique Cryptosystème de McEliece Codes de Goppa (classiques) Cryptographie post-quantique Attaque par canal auxiliaire (/ caché) Attaque temporelle Attaque par analyse de consommation Contre-mesure Public key cryptography McEliece cryptosystem Goppa codes Post-quantum cryptography Side-channel attacks Timing attack Power analysis attack Countermeasure
238	Blockchain Technology : a new domain for Cyber Forensics Rasool, Muhammad Ahsan, Muhammad Shafiq, Hafiz January 2018 (has links) Traditional database with no prior security measures is becoming challenging in the era of data technology. Database storage on a central location with single point of failure and vulnerable to cyber attacks is getting exposed to big risk of being hacked with the evolution of powerful machines and modern hacking techniques. Since its commencement, the BlockChain technology has shown a promising performance for application buildup in diversed fields of life from cryptocurrency to smart contracts and decentralized applications. Although multiple studies on privacy, data confidentiality and security issues of BlockChain are performed but a systematic examination is still needs attention. In this thesis work we conduct a systematic study about the vulnerabilities of BlockChain system and review the security enhancement solutions that may point to a good future direction for further research into the area of BlockChain technology and its applications. Smart contracts are self-executable objects hosted on the 2nd generation blockchain like Ethereum, carry billions of SEK worth of cryptocoins and cannot be updated once deployed. Smart contracts are generally considered secure objects but the systematic analysis of technology and source code exposes a new class of vulnerabilities which are more likely an ethical aspect of programming than the software coding errors. Besides the literature review we empower our results with a static code analysis especially with the perspective of cyber forensics. Blockchain Bitcoin Ethereum Ethereum Virtual Machine Smart Contracts vulnerabilities Securify Remix IDE Solidity Locked Funds Initial Coin Offering cryptocurrency attacks bytecode analysis wallet Public Key Untested Code Elektroteknik och elektronik Other Engineering and Technologies Annan teknik Computer Systems Datorsystem
239	Criptografia de chave pública sem certificado / Certificateless public key cryptography Denise Hideko Goya 16 December 2011 (has links) A criptografia de chave pública sem certificado (certificateless) é uma alternativa ao modelo convencional de criptografia assimétrica, pois a autenticação da chave pública ocorre implicitamente durante a execução dos protocolos, sem a necessidade de gerenciamento e distribuição de certificados digitais. Potencialmente reduz custos computacionais e o nível de segurança alcançado é maior quando comparado ao modelo baseado em identidade. Nesta tese de doutorado, modelos formais de segurança para acordo de chave com autenticação sem certificado são aprimorados visando dois objetivos paralelos: (1) aumentar o nível de confiança que usuários podem depositar na autoridade geradora de chaves secretas parciais e (2) viabilizar protocolos que sejam eficientes computacionalmente e com propriedades de segurança relevantes, dentre as quais se inclui resistência a ataques de adversários que têm total controle do canal de comunicação e que podem substituir chaves públicas de usuários por valores arbitrários. Para atestar que as melhorias efetuadas são praticáveis e possibilitam que os objetivos sejam alcançados, novos protocolos são propostos para o caso que envolve dois participantes na comunicação. Os protocolos são provados seguros, usando-se técnica de redução de problemas computacionais. / Certificateless public key cryptography is an alternative model to traditional asymmetric key cryptography, because the public key authentication occurs implicitly during a protocol run, with no need of digital certificates management and distribution. It has the potential to reduce computing costs, and it allows a higher security level than the one in the identity-based model. In this PhD thesis, formal security models for certificateless authenticated key agreement are improved with two independent objectives: (1) to increase the trust level for the partial secret key generating authority on which users rely, and (2) to enable computationally efficient protocols, with significant security properties, such as resistance against attacks from adversaries with full control of the communication channel, and from adversaries who are able to replace users\' public keys by any chosen value. In order to demonstrate that these improvements made are feasible and achieve the objectives, new protocols are proposed in the two-party case. These protocols are proved secure by using reduction techniques for provable security. Acordo de chave com autenticação Criptografia sobre curva elíptica Emparelhamento bilinear Modelos de segurança Segurança de sistemas de informação Segurança demonstrável Authenticated key agreement Bilinear pairing Certificateless public key cryptography Elliptic curve cryptography Information systems security Provable security Security models
240	Data Encryption on a Network Luque González, Jorge, Arenchaga Fernandez, Ignacio January 2010 (has links) In this project you can find a study about different encryption algorithms, which are use to safeguard the information on messages over the network. We have developed a client-server application which will send information through the network which has to be secured. There are two kinds of encryption algorithms, the symmetric and the asymmetric key algorithms. Both were used to establish the communication, the asymmetric algorithm (RSA) is used to set up a symmetric key and then, all the communication process is done only with the symmetric algorithm (Blowfish). / En este proyecto encontraras un estudio sobre diferentes algoritmos de encriptación, que son usados para salvaguardar la información en mensajes por la red. Además hemos desarrollado una aplicación cliente-servidor que enviara información a través de la red de forma segura. Hay dos tipos de algoritmos de encriptación, los simétricos y los asimétricos. Ambos tipos de algoritmos son utilizados para establecer la comunicación, el asimétrico (RSA) es utilizado para establecer la clave del simétrico y a partir de entonces se utilizara exclusivamente el algoritmo simétrico (Blowfish). encryption decryption DES Triple-DES security serpent blowfish Diffie-Hellman RSA AES private key public key security attack brute force man-in-the-middle. encriptacion decriptacion DES Triple-DES seguridad serpent blowfish Diffie-Hellman RSA AES clave privada clave pública ataque fuerza bruta man-in-the-middle Computer Sciences Datavetenskap (datalogi) Telecommunications Telekommunikation Computer Sciences Datavetenskap (datalogi)

Search results