Contributions to the privacy provisioning for federated identity management platforms

Identity information, personal data and user’s profiles are key assets for organizations and companies by becoming the use of identity management (IdM) infrastructures a prerequisite for most companies, since IdM systems allow them to perform their business transactions by sharing information and customizing services for several purposes in more efficient and effective ways. Due to the importance of the identity management paradigm, a lot of work has been done so far resulting in a set of standards and specifications. According to them, under the umbrella of the IdM paradigm a person’s digital identity can be shared, linked and reused across different domains by allowing users simple session management, etc. In this way, users’ information is widely collected and distributed to offer new added value services and to enhance availability. Whereas these new services have a positive impact on users’ life, they also bring privacy problems. To manage users’ personal data, while protecting their privacy, IdM systems are the ideal target where to deploy privacy solutions, since they handle users’ attribute exchange. Nevertheless, current IdM models and specifications do not sufficiently address comprehensive privacy mechanisms or guidelines, which enable users to better control over the use, divulging and revocation of their online identities. These are essential aspects, specially in sensitive environments where incorrect and unsecured management of user’s data may lead to attacks, privacy breaches, identity misuse or frauds. Nowadays there are several approaches to IdM that have benefits and shortcomings, from the privacy perspective. In this thesis, the main goal is contributing to the privacy provisioning for federated identity management platforms. And for this purpose, we propose a generic architecture that extends current federation IdM systems. We have mainly focused our contributions on health care environments, given their particularly sensitive nature. The two main pillars of the proposed architecture, are the introduction of a selective privacy-enhanced user profile management model and flexibility in revocation consent by incorporating an event-based hybrid IdM approach, which enables to replace time constraints and explicit revocation by activating and deactivating authorization rights according to events. The combination of both models enables to deal with both online and offline scenarios, as well as to empower the user role, by letting her to bring together identity information from different sources. Regarding user’s consent revocation, we propose an implicit revocation consent mechanism based on events, that empowers a new concept, the sleepyhead credentials, which is issued only once and would be used any time. Moreover, we integrate this concept in IdM systems supporting a delegation protocol and we contribute with the definition of mathematical model to determine event arrivals to the IdM system and how they are managed to the corresponding entities, as well as its integration with the most widely deployed specification, i.e., Security Assertion Markup Language (SAML). In regard to user profile management, we define a privacy-awareness user profile management model to provide efficient selective information disclosure. With this contribution a service provider would be able to accesses the specific personal information without being able to inspect any other details and keeping user control of her data by controlling who can access. The structure that we consider for the user profile storage is based on extensions of Merkle trees allowing for hash combining that would minimize the need of individual verification of elements along a path. An algorithm for sorting the tree as we envision frequently accessed attributes to be closer to the root (minimizing the access’ time) is also provided. Formal validation of the above mentioned ideas has been carried out through simulations and the development of prototypes. Besides, dissemination activities were performed in projects, journals and conferences.Programa Oficial de Doctorado en Ingeniería TelemáticaPresidente: María Celeste Campo Vázquez.- Secretario: María Francisca Hinarejos Campos.- Vocal: Óscar Esparza Martí

AnonySense: A System for Anonymous Opportunistic Sensing

We describe AnonySense, a privacy-aware system for realizing pervasive applications based on collaborative, opportunistic sensing by personal mobile devices. AnonySense allows applications to submit sensing \emphtasks\/ to be distributed across participating mobile devices, later receiving verified, yet anonymized, sensor data \emphreports\/ back from the field, thus providing the first secure implementation of this participatory sensing model. We describe our security goals, threat model, and the architecture and protocols of AnonySense. We also describe how AnonySense can support extended security features that can be useful for different applications. We evaluate the security and feasibility of AnonySense through security analysis and prototype implementation. We show the feasibility of our approach through two plausible applications: a Wi-Fi rogue access point detector and a lost-object finder

Becoming Artifacts: Medieval Seals, Passports and the Future of Digital Identity

What does a digital identity token have to do with medieval seals? Is the history of passports of any use for enabling the discovery of Internet users\u27 identity when crossing virtual domain boundaries during their digital browsing and transactions? The agility of the Internet architecture and its simplicity of use have been the engines of its growth and success with the users worldwide. As it turns out, there lies also its crux. In effect, Internet industry participants have argued that the critical problem business is faced with on the Internet is the absence of an identity layer from the core protocols of its logical infrastructure. As a result, the cyberspace parallels a global territory without any identification mechanism that is reliable, consistent and interoperable across domains. This dissertation is an investigation of the steps being taken by Internet stakeholders in order to resolve its identity problems, through the lenses of historical instances where similar challenges were tackled by social actors. Social science research addressing the Internet identity issues is barely nascent. Research on identification systems in general is either characterized by a paucity of historical perspective, or scantily references digital technology and online identification processes. This research is designed to bridge that gap. The general question at its core is: How do social actors, events or processes enable the historical emergence of authoritative identity credentials for the public at large? This work is guided by that line of inquiry through three broad historical case studies: first, the medieval experience with seals used as identity tokens in the signing of deeds that resulted in transfers of rights, particularly estate rights; second, comes the modern, national state with its claim to the right to know all individuals on its territory through credentials such as the passport or the national identity card; and finally, viewed from the United States, the case of ongoing efforts to build an online digital identity infrastructure. Following a process-tracing approach to historical case study, this inquiry presents enlightening connections between the three identity frameworks while further characterizing each. We understand how the medieval doctrines of the Trinity and the Eucharist developed by schoolmen within the Church accommodated seals as markers of identity, and we understand how the modern state seized on the term `nationality\u27 - which emerged as late as in the 19th century - to make it into a legal fiction that was critical for its identification project. Furthermore, this investigation brings analytical insights which enable us to locate the dynamics driving the emergence of those identity systems. An ordering of the contributing factors in sequential categories is proposed in a sociohistorical approach to explain the causal mechanisms at work across these large phenomena. Finally this research also proposes historically informed projections of scenarios as possible pathways to the realization of authoritative digital identity. But that is the beginning of yet another story of identity