An investigation of issues of privacy, anonymity and multi-factor authentication in an open environment

This thesis performs an investigation into issues concerning the broad area ofIdentity and Access Management, with a focus on open environments. Through literature research the issues of privacy, anonymity and access control are identified. The issue of privacy is an inherent problem due to the nature of the digital network environment. Information can be duplicated and modified regardless of the wishes and intentions ofthe owner of that information unless proper measures are taken to secure the environment. Once information is published or divulged on the network, there is very little way of controlling the subsequent usage of that information. To address this issue a model for privacy is presented that follows the user centric paradigm of meta-identity. The lack of anonymity, where security measures can be thwarted through the observation of the environment, is a concern for users and systems. By an attacker observing the communication channel and monitoring the interactions between users and systems over a long enough period of time, it is possible to infer knowledge about the users and systems. This knowledge is used to build an identity profile of potential victims to be used in subsequent attacks. To address the problem, mechanisms for providing an acceptable level of anonymity while maintaining adequate accountability (from a legal standpoint) are explored. In terms of access control, the inherent weakness of single factor authentication mechanisms is discussed. The typical mechanism is the user-name and password pair, which provides a single point of failure. By increasing the factors used in authentication, the amount of work required to compromise the system increases non-linearly. Within an open network, several aspects hinder wide scale adoption and use of multi-factor authentication schemes, such as token management and the impact on usability. The framework is developed from a Utopian point of view, with the aim of being applicable to many situations as opposed to a single specific domain. The framework incorporates multi-factor authentication over multiple paths using mobile phones and GSM networks, and explores the usefulness of such an approach. The models are in tum analysed, providing a discussion into the assumptions made and the problems faced by each model.Adobe Acrobat Pro 9.5.1Adobe Acrobat 9.51 Paper Capture Plug-i

Privacidade em redes de próxima geração

Doutoramento em Engenharia InformáticaIn the modern society, communications and digital transactions are becoming the norm rather than the exception. As we allow networked computing devices into our every-day actions, we build a digital lifestyle where networks and devices enrich our interactions. However, as we move our information towards a connected digital environment, privacy becomes extremely important as most of our personal information can be found in the network. This is especially relevant as we design and adopt next generation networks that provide ubiquitous access to services and content, increasing the impact and pervasiveness of existing networks. The environments that provide widespread connectivity and services usually rely on network protocols that have few privacy considerations, compromising user privacy. The presented work focuses on the network aspects of privacy, considering how network protocols threaten user privacy, especially on next generation networks scenarios. We target the identifiers that are present in each network protocol and support its designed function. By studying how the network identifiers can compromise user privacy, we explore how these threats can stem from the identifier itself and from relationships established between several protocol identifiers. Following the study focused on identifiers, we show that privacy in the network can be explored along two dimensions: a vertical dimension that establishes privacy relationships across several layers and protocols, reaching the user, and a horizontal dimension that highlights the threats exposed by individual protocols, usually confined to a single layer. With these concepts, we outline an integrated perspective on privacy in the network, embracing both vertical and horizontal interactions of privacy. This approach enables the discussion of several mechanisms to address privacy threats on individual layers, leading to architectural instantiations focused on user privacy. We also show how the different dimensions of privacy can provide insight into the relationships that exist in a layered network stack, providing a potential path towards designing and implementing future privacy-aware network architectures.Na sociedade moderna, as comunicações e transacções digitais estão a tornar-se a regra e não a excepção. À medida que permitimos a intromissão de dispositivos electrónicos de rede no nosso quotidiano, vamos construíndo um estilo de vida digital onde redes e dispositivos enrirquecem as nossas interacções. Contudo, ao caminharmos para um ambiente digital em rede, a nossa privacidade vai-se revestindo de maior importãncia, pois a nossa informação pessoal passa a encontrar-se cada vez mais na rede. Isto torna-se particularmente relevante ao adoptarmos redes de próxima geração, que permitem acesso ubíquo a redes, serviços e conteúdos, aumentando o impacte e pervasividade das redes actuais. Os ambientes onde a conectividade e os serviços se tornam uma constante, assentam em protocolos de rede que normalmente contemplam poucas considerações sobre privacidade, comprometendo desta forma o utlizador. O presente trabalho centra-se nos aspectos de privacidade que dizem respeito à rede devido à forma como os protocolos são utilizados nas diferentes camadas, e que resultando em ameaças à privacidade do utilizador. Abordamos especificamente os identificadores presentes nos protocolos de rede, e que são essenciais à sua função. Neste contexto exploramos a possibilidade destes identificadores comprometerem a privacidade do utilizador através da informação neles contida, bem como das relações que podem ser estabelecidas entre identificadores de diferentes protocolos. Após este estudo centrado nos identificadores, mostramos como a privacidade em redes pode ser explorada ao longo de duas dimensões: uma dimensão que acentua as relações verticais de privacidade, cruzando vários protocolos até chegar ao utilizador, e uma dimensão horizontal que destaca as ameaças causadas por cada protocolo, de forma individual, normalmente limitadas a uma única camada. Através destes conceitos, mostramos uma visão integrada de privacidade em redes, abrangendo tanto as interacçoes de privacidade verticais como as horizontais. Esta visão permite discutir vários mecanismos para mitigar ameaças específicas a cada camada de rede, resultando em instânciações arquitecturais orientadas à privacidade do utilizador. Finalmente, mostramos como as diferentes dimensões de privacidade podem fornecer uma visão diferente sobre as relações estabelecidas na pilha protocolar que assenta em camadas, mostrando um caminho possível para o desenvolvimento de futuras arquitecturas de rede com suporte para privacidade

Resilient Anonymity Networks

Unverkettbare Nachrichten sind ein Grundbaustein anonymer Kommunikation. Anonymisierungsnetze schützen mittels Unverkettbarkeit, wer mit wem kommuniziert sowie die Identität der Beteiligten einer Kommunikationsbeziehung. Anonymisierungsnetze benötigen Kooperation, da die Anonymität durch Ressourcen anderer Teilnehmer geschützt wird. Wenn die Kosten und der Nutzen eines Anonymisierungsnetzes transparent sind, ergeben sich Zielkonflikte zwischen rationalen Teilnehmern. Es wird daher untersucht, inwiefern daraus resultierendes egoistisches Verhalten die Widerstandsfähigkeit dieser Netze beeinträchtigt. Störungen werden in einem spieltheoretischen Modell untersucht, um widerstandsfähige Konfigurationen von Anonymisierungsnetzen zu ermitteln. Eine weitere Störquelle sind Überflutungsangriffe mittels unverkettbarer Nachrichten. Es soll sowohl die Verfügbarkeit als auch die Anonymität geschützt werden. Dazu wird Unverkettbarkeit für Nachrichten aufrecht erhalten, außer wenn die Senderate eines Nachrichtenstroms eine Richtlinie überschreitet. Innerhalb verkettbarer Nachrichten können Überflutungsangriffe erkannt werden. Darüber kann die Verfügbarkeit des Netzdienstes geschützt werden

Technical challenges of network anonymity

The Internet promises an ever-increasing variety of services available anytime, almost anywhere, to anyone of just about any experience level. Thus, in many respects, the virtual world has become a viable alternative to our real world, where we can buy anything from a dishwasher to personal services, or publish any information we choose on a personal web site. With all of the convenience and freely available information that this virtual world provides, it has one major problem: in the real world people can nearly always exert some control over their privacy. If they choose, they can study in absolute solitude or meet with others in private rooms, or they can anonymously buy a magazine. However, on the Internet, users have few controls, if any, over the privacy of their actions. Each communication leaves trails here or there and there is always someone who can follow these trails back to the user. Thus, should we just forget about having privacy in the Internet as others have proclaimed? The one path towards enabling true network privacy is to provide anonymity. Anonymity services can allow users to carry out their activities anonymously and unobservably on the Internet. In this work, we investigate the following technical questions: what is network anonymity, what are the various techniques for reliably achieving anonymity, and what are their associated impacts on network performance and user experience. Our emphasis is on deployable systems for the Internet that provide strong anonymity against a strong attacker model. We present the network anonymity techniques (algorithms) suggested in the past and the ones currently in use, and then we discuss possible anonymity techniques of the future. We present the accepted terminology for discussing anonymity, and the definition and different measures of anonymity. However, throughout our discussions we pay particular attention to the analysis of network performance in the presence of anonymity mechanisms