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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.
51

Electronic Identification : Focus on bank services and security

Eriksson, Oskar, Maric, Kristian, Olsberg, Hans January 2005 (has links)
No description available.
52

Přístupy k auditu infrastruktury veřejných klíčů / Public Key Infrastructure audit approaches

Pěnka, Michal January 2010 (has links)
The aim of this work is to introduce fundamental concepts of public key infrastructure. Basic requirements for communication and related problems are presented. The solution of these problems can be found in cryptography. Different types of cyphers and infrastructures based on assymetric cryptography are described. The infrastructure types involve hierarchical system of certificate authorities and the web of trust. Furthermore, there is a list and description of cryptography software which can be used in the field of public key infrastructre. The main topic of this thesis is the audit of public key infrastructure. Audit can be supported by several available standards, e.g. WebTrust for Certificate Authorities, ETSI TS 101 456, ETSI TS 102 042 and ISO 21188:2006. This paper systematically describes these standards and using statistical methods compares and evaluates their complexity.
53

Analysing the behaviour of a smart card based model for secure communication with remote computers over the internet

Bhatt, Deep Vardhan 12 July 2011 (has links)
This dissertation presents the findings of a generic model aimed at providing secure communication with remote computers via the Internet, based on smart cards. The results and findings are analysed and presented in great detail, in particular the behaviour and performance of smart cards when used to provide the cryptographic functionality. Two implemented models are presented. The first model uses SSL to secure the communication channel over the Internet while using smart cards for user authentication and storage of cryptographic keys. The second model presents the SSH for channel security and smart cards for user authentication, key storage and actual encryption and decryption of data. The model presented is modular and generic by nature, meaning that it can easily be modified to accept the newer protocol by simply including the protocols in a library and with a minor or no modification to both server and client application software. For example, any new algorithm for encryption, key exchange, signature, or message digest, can be easily accommodated into the system, which proves that the model is generic and can easily be integrated into newer technologies. Similarly, smart cards are used for cryptography. Two options are presented: first the smart cards only store the algorithm keys and user authentication, and secondly, smart cards are used for storing the algorithm keys, user authentication, and actual data encryption or decryption, as the requirement may dictate. This is very useful, for example, if data to be transferred is limited to a few bytes, then actual data encryption and decryption is performed using smart cards. On the other hand, if a great deal of data is to be transferred, then only authentication and key storage are performed with smart cards. The model currently uses 3DES with smart card encryption and decryption, because this is faster and consumes fewer resources when compared to RSA. Once again, the model design is flexible to accommodate new algorithms such as AES or IDEA. Important aspects of the dissertation are the study and analysis of the security attacks on smart card use. Several smart card attack scenarios are presented in CHAPTER 3, and their possible prevention is also discussed in detail. AFRIKAANS : Hierdie verhandeling bied die bevindinge van 'n generiese model wat daarop gemik is om veilige kommunikasie te voorsien met 'n afstandsrekenaar via die Internet en op slimkaarte gebaseer. Die resultate en bevindings word ontleed en breedvoerig aangebied, veral die gedrag en werkverrigting van slimkaarte wanneer hulle gebruik word om die kriptografiese funksionaliteit te voorsien. Daar word twee geïmplementeerde modelle aangebied. Die eerste model gebruik SSL om die kommunikasiekanaal oor die Internet te beveilig terwyl slimkaarte vir gebruikerbekragtiging en stoor van kriptografiese sleutels gebruik word. Die tweede model bied die SSH vir kanaalsekuriteit en slimkaarte vir gebruikergeldigheidvasstelling, sleutelstoor en werklike kodering en dekodering van data. Die model wat aangebied word, is modulêr en generies van aard, wat beteken dat dit maklik gewysig kan word om die jongste protokolle te aanvaar deur bloot die protokolle by 'n programbiblioteek met geringe of geen wysiging van beide die bediener- en kliënttoepassingsagteware in te sluit. Byvoorbeeld, enige nuwe algoritme vir kodering, sleuteluitruiling, handtekening of boodskapbondeling kan maklik in die stelsel gehuisves word, wat bewys dat die model generies is en maklik in jonger tegnologieë geïntegreer kan word. Slimkaarte word op soortgelyke wyse vir kriptografie gebruik. Daar word twee keuses aangebied: eerstens stoor die slimkaarte slegs die algoritmesleutels en gebruikergeldigheidvasstelling en tweedens word slimkaarte gebruik om die algoritmesleutels, gebruikergeldigheidvasstelling en werklike datakodering en –dekodering te stoor na gelang van wat vereis word. Dit is baie nuttig, byvoorbeeld, wanneer data wat oorgedra moet word, tot 'n paar grepe beperk is, word die eintlike datakodering en – dekodering uitgevoer deur slimkaarte te gebruik. Andersyds, indien 'n groot hoeveelheid data oorgedra moet word, word slegs geldigheidvasstelling en stoor met slimkaarte uitgevoer. Die model gebruik tans 3DES met slimkaartkodering en –dekodering omdat dit vinniger is en minder hulpbronne gebruik vergeleke met RSA. Die modelontwerp is weer eens buigsaam om nuwe algoritmes soos AES of IDEA te huisves. Nog 'n belangrike aspek van die verhandeling is om die sekuriteitaanvalle op slimkaartgebruik te ondersoek en te ontleed. Verskeie slimkaartaanvalscenario's word in Hoofstuk 3 aangebied en die moontlike voorkoming daarvan word ook breedvoerig bespreek. / Dissertation (MEng)--University of Pretoria, 2011. / Electrical, Electronic and Computer Engineering / unrestricted
54

Nutzung von Sozialen Netzwerk-Plattformen für die Verteilung von Public Keys

Hülder, Malte, Wolff-Marting, Vincent, Gruhn, Volker 29 January 2019 (has links)
Public Key Infrastrukturen (PKI) sind schon seit einigen Jahren bekannt, jedoch setzen sie sich nur sehr zögerlich durch, insbesondere im privaten Bereich. In diesem Artikel werden einige Hürden für die existierenden Ansätze (besonders das Web-of-Trust) beschrieben und es wird ein Lösungsansatz vorgestellt, der auf der Integration von sozialen Netzwerk-Plattformen mit den bestehenden Schlüssel-Servern beruht. Eine prototypische Umsetzung der genannten Ansätze zeigt, dass diese praktisch einsetzbar sind und die Usability von PKI verbessern können.
55

Security for Mobile Payment Transaction

Desta, Girmay January 2012 (has links)
The advancement of ICT in a variety of sectors helped in improving the time consuming and rigid service into fast and flexible service that is closer to the reach of individuals. For instance, mobile applications have evolved in different sectors such as healthcare patient support, geographic mapping and positioning, banking, e-commerce payment services and others. This study focuses on one of the most sensitive applications, which is mobile payment. Mobile payment system being one of the widely expanding mobile services, it has security concerns that prevented its wide acceptance. Some of the main security services given prior attention in mobile payment are issues of privacy, authentication and confidentiality. The research concentrates on the strong authentication of a mobile client to its server, securing the credit card* information and use of mobile card reader while making payments that enable customers to protect privacy of financial credentials. The strong authentication mechanism mainly follows the NIST standard publications namely, FIPS PUB 201 and FIPS 196; which are standards on Entity Authentication using public key cryptography and PKI credential storage Personal Identity Verification (PIV) card respectively. The proposed secure Credit Card Information (CCI) storage is in a secure element in order to prevent tampering of stored data. The secure element options are microSD, UICC, Smartcard (together with digital certificate and service ticket). During making payments, the payment information encrypted using a shared key is securely sent to payment server. A demo mobile application as proof of concept was implemented in a simulated lab (KTH SecLab), which has all the necessary infrastructure setup (servers, card reader) for testing the proposed solution. The paper was able to proof the concept of secure payment by enhancing the authentication, confidentiality and privacy of payment information. However, the demo for Strong Authentication did not completely succeed as expected due to unexpected bugs in the early version of card reader SDK.
56

Framework to Implement Authentication, Authorization and Secure Communications in a Multiuser Collaborative CAx Environment

Mensah, Francis 01 December 2014 (has links) (PDF)
Computer Aided Design (CAD) applications have historically been based on a single user per application architecture. Although this architecture is still popular to date, it does have several drawbacks. First of all the single user CAD architecture inhibits a concurrent engineering design process where several designers can work on the same model simultaneously. This limitation introduces time inefficiency especially when a project involves geographically dispersed designers. A solution to these drawbacks could be a transition from the traditional single user CAD architecture to a multiuser collaborative architecture. Advances in computer networking technologies, especially relating to the Internet, have provided the needed tools to make this transition a reality, thus making it possible for designers to simultaneously work on geometric models from one or more networked computers regardless of the location of the user. This new paradigm is expected to improve collaboration and greatly reduce product design times and consequently reduce cost and improve productivity. The multi-user architecture will, however, also require reliable security mechanisms to ensure its successful deployment in an enterprise environment where protection of intellectual property is of critical importance. This thesis proposes a framework to implement authentication, authorization and secure data communications in a multiuser collaborative CAD software system. This framework has been tested on an emerging multiuser collaborative CAD system called v-CAx being developed at Brigham Young University.
57

Evaluation of Decentralized Alternatives to PKI for IoT Devices : A litterature study and proof of concept implementation to explore the viability of replacing PKI with decentralized alternatives

Magnusson, Sebastian January 2018 (has links)
This report is the result of an investigation into current possibilities to use blockchain or other distributed ledger technologies for identification and authentication in an Internet-of-Things (IoT) setting. During the course of the project, several different distributed ledgers have been examined and their strengths and weaknesses analyzed with respect to their potential use in connected devices with constrained resources. After investigating whether there are any solutions providing identification and authentication through distributed ledgers available today, one was chosen for implementation in a Proof of Concept (PoC), where the solution was tested on a certain piece of hardware representing an IoT-device. The performance of the PoC was then analyzed and evaluated. The results of the literature study as well as the tests on the PoC led to the conclusion that a number of factors prevent such a solution from being a viable alternative to current solutions. However, as the technology involved is still in its infancy and developing rapidly, this verdict may be subject to change in the future. The advancements required for such a solution to become viable are: improved consensus models, light nodes and possibly fundamentally new and improved distributed ledger technologies. / Denna rapport är resultatet av en undersökning av nuvarande möjligheter att använda blockkedje- eller annan distribuerade-liggare-teknologi för identifikation och autentisering i en sakernas internet (IoT). Under arbetets gång har ett antal olika distribuerade liggare undersökts och deras respektive styrkor och svagheter har analyserats i förhållande till deras potentiella användbarhet i uppkopplade enheter med begränsad hårdvaruprestanda. Efter att ha undersökt om det finns några lösningar som erbjuder identifikation och autentisering genom distribuerade liggare tillgängliga idag valdes en för att implementeras i en konceptvalidering där lösningen testades på en viss hårdvara som representerade en enhet i IoT. Konceptvalideringens prestanda analyserades därefter och utvärderades. Resultaten av litteraturstudien och testerna av konceptvalideringen ledde till slutsatsen att ett antal faktorer hindrar en sådan lösning från att vara ett gångbart alternativ till dagens lösningar. Då teknologin i fråga fortfarande är i sin linda och utvecklas snabbt kan dock denna slutsats komma att ändras i framtiden. Framsteg som behöver göras för att en sådan lösning ska kunna vara praktisk är förbättrade konsensusmodeller, lätta noder och möjligen grundligen nya och förbättrade distribuerade liggare.
58

LF-PKI: Practical, Secure, and High-Performance Design and Implementation of a Lite Flexible PKI / LF-PKI: Praktisk, säker och Högpresterande design och Implementering av Lite Flexible PKI

Xu, Yongzhe January 2022 (has links)
Today’s Web Public Key Infrastructure (PKI) builds on a homogeneous trust model. All Certificate Authorities (CAs) are equally trusted once they are marked as trusted CAs on the client side. As a result, the security of the Web PKI depends on the weakest CA. Trust heterogeneity and flexibility can be introduced in today’s Web PKI to mitigate the problem. Each client could have different levels of trust in each trusted CA, according to the properties of each CA, such as the location, reputation and scale of the CA. As a result, the loss caused by the compromise of a less trusted CA will be relieved. In this work, we study Flexible-PKI (F-PKI), which is an enhancement of Web PKI, and propose Lite Flexible-PKI (LF-PKI) to address the limitations of F-PKI. LF-PKI is designed to securely and efficiently manage domain policies and enable trust heterogeneity on the client side. The domain owner can issue domain policies for their domains, and the client will have a complete view of the domain policies issued for a specific domain. Based on the collection of domain policies from LF-PKI, trust heterogeneity can be achieved on the client side. Each client will choose the domain policies based on the trust levels of the CA. On the basis of the LF-PKI design, a high-performance implementation of LF-PKI was developed, optimized, and analyzed. The optimized implementation can provide the LF-PKI services for worldwide domains on a single server with moderate hardware. / Dagens Web Public Key Infrastructure (PKI) bygger på en homogen förtroendemodell. Alla certifikatutfärdare (CA) är lika betrodda när de är markerade som betrodda certifikatutfärdare på klientsidan. Som ett resultat beror säkerheten för webb-PKI på den svagaste CA. Förtroendeheterogenitet och flexibilitet kan införas i dagens webb-PKI för att mildra problemet. Varje klient kan ha olika nivåer av förtroende för varje betrodd certifikatutfärdare, beroende på egenskaperna hos varje certifikatutfärdare, såsom certifikatutfärdarens plats, rykte och omfattning. Som ett resultat kommer förlusten som orsakats av kompromissen av en mindre pålitlig CA att avhjälpas. I detta arbete studerar vi Flexible-PKI (F-PKI), som är en förbättring av webb-PKI, och föreslår Lite Flexible-PKI (LF-PKI) för att ta itu med begränsningarna hos F-PKI. LF-PKI är utformad för att säkert och effektivt hantera domänpolicyer och möjliggöra förtroendeheterogenitet på klientsidan. Domänägaren kan utfärda domänpolicyer för sina domäner, och klienten kommer att ha en fullständig bild av domänpolicyerna som utfärdats för en specifik domän. Baserat på insamlingen av domänpolicyer från LF-PKI kan förtroendeheterogenitet uppnås på klientsidan. Varje klient kommer att välja domänpolicyer baserat på förtroendenivåerna för CA. På basis av LF-PKI-designen utvecklades, optimerades och analyserades en högpresterande implementering av LF-PKI. Den optimerade implementeringen kan tillhandahålla LF-PKI-tjänster för världsomspännande domäner på en enda server med måttlig hårdvara.
59

Secure and Privacypreserving V2X multicast DNS

Atif, Ayub, Arieltan, Justin January 2020 (has links)
The Domain Name System is a hierarchical naming system that provides information of network resources or services given domain names. DNS applications in vehicular networks raise new challenges with regards to security and privacy of vehicles. In particular, vehicular communications outside the coverage of roadside infrastructure needs to be preserved. Multicast DNS is proposed as a method to restrict queries to vehicles in a Vehicle-to-Everything environment which could include other connected devices. Contemporary DNS applications rely on robust security protocols provided by the DNS Security Extensions to authenticate responses and verify resource records. Vehicular DNS communications need authentication to verify the source and legitimacy of DNS resource records. This can be achieved through multihop Vehicle- to-Vehicle communications to reach a name server supplemented by a novel approach to verify records using the Bloom filter.In this thesis, we analyze the security and privacy risks posed by a non-authenticated baseline communication protocol. We then build a secure and privacy-preserving networked system based on pseudonym certificate-based public key infrastructure solution. The experimental analysis confirmed the improvement on security and privacy at the cost of communication and computation overhead. / Domännamnssystemet är en hierarkisk benämningssystem som ger information om nätverksresurser eller tjänster för givna domännamn. DNS application i fordon nätverk framkallar nya utmaningar när det handlar om datasäkerhet och fordons integritet. Det är särskilt fordon kommunikation utanför vägkant-infrastrukturens räckvidd som behöver bevara och försäkra operationer av DNS applikation i fordon nätverk. Multicast DNS är en föreslagen metod för att begränsa förfrågan till fordon i en fordon-till-all-miljö som kan inkludera andra anslutna enheter. Nuvarande applikationer förlitar sig på en robust säkerhetsprotokoll som kommer från DNS säkerhetsförlängning för att autentisera svar och verifiera resurs rekord. Fordon DNS kommunikationer behöver autentisering för att verifiera källor och legitimitet av DNS resurs rekord. Detta kan uppnås genom multihop fordon-till-fordon kommunikation för att ansluta sig till en namn server med hjälp av en ny metod för att verifiera uppgifter med hjälp av bloomfilter datastruktur.I tesen analyserar vi risken som finns i en icke-autentiserad integritets-läckande kommunikationsprotokoll. Vi bygger sedan ett nätverk och använder en pseudonym certifikatbaserad publik nyckel infrastruktur lösning för att undersöka förbättringar inom säkerhet och integritet. Analysen från experimenten visar att det finns en förbättring för säkerhet och integritet i utbyte mot tidsprestanda, vilket är en intressant kompromiss.
60

Protocolo multiplataforma no centralizado para comunicaciones multimedia seguras

Aguirre Pastor, José Vicente 27 January 2016 (has links)
En este trabajo se propone y desarrolla una topología en k-hipercubos que resuelve los principales inconvenientes asociados a la topología en hipercubo convencional. Los resultados obtenidos son muy prometedores, con aplicaciones tanto en el campo de la voz sobre IP, como en muchos otros campos que precisen de un intercambio de información muchos a muchos. Sobre la topología propuesta se define el protocolo Darkcube, que es una propuesta de protocolo totalmente distribuido basado en el concepto de darknet, posibilitando la realización de conversaciones muchos a muchos incluyendo audio, vídeo, texto y datos de geoposicionamiento, entre otros. También se propone un método de codificación de coordenadas de geoposicionamiento que resulta especialmente eficiente en el aprovechamiento del ancho de banda sobrante en las comunicaciones muchos a muchos que proporciona Darkcube. Durante el desarrollo de este trabajo, se ha implementado el simulador DarkcubeEmu; herramienta que posibilita la obtención de resultados relevantes en términos de la calidad de la comunicación. Finalmente, utilizando como base el protocolo Darkcube, se propone un protocolo de seguridad que traslada un esquema de infraestructura de clave pública a un protocolo totalmente distribuido, como es Darkcube; garantizando, de esta forma, la confidencialidad en las comunicaciones y la legitimidad de la identidad asociada a cada uno de sus miembros.

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