IEEE International Conference on Information Technology (ITRE’03), IEEE, pp. 274-278, 2003. DOI
The combined use of authorization and authentication infrastructures has led to AAIs (authorization and authentication infrastructures). These new infrastructures supply identification and authorization services to a distributed environment There are many possibilities of linkages to get AAIs; one of them is to include the PMI (privilege management infrastructure) as authorization infrastructure and an authentication infrastructure that can be a PKI (public key infrastructure) or kerberos. This symbiosis gives service to applications and servers. However, in physical environments where the physical presence of an individual is required, it is necessary to use biometric systems. This paper describes the development of a solution that combines the relationship between the biometric based systems and the PMIs to finally obtain the biometric AAI.
8th International Workshop on Security and Trust Management (STM 2012), A. Jøsang, P. Samarati, and M. Petrocchi Eds., LNCS 7783, Springer, pp. 113-128, 2013. DOI
During the last years, many trust and reputation models have been proposed, each one targeting different contexts and purposes, and with their own particularities. While most contributions focus on defining ever-increasing complex models, little attention has been paid to the process of building these models inside applications during their implementation. The result is that models have traditionally considered as ad-hoc and after-the-fact solutions that do not always fit with the design of the application. To overcome this, we propose an object-oriented development framework onto which it is possible to build applications that require functionalities provided by trust and reputation models. The framework is extensible and flexible enough to allow implementing an important variety of trust models. This paper presents the framework, describes its main components, and gives examples on how to use it in order to implement three different trust models.
International Journal of Information Security, vol. 13, issue 2, Springer, pp. 199-215, 2014. DOI (I.F.: 0.963)
Identity management is an almost indispensable component of today’s organizations and companies, as it plays a key role in authentication and access control; however, at the same time it is widely recognized as a costly and time-consuming task. The advent of cloud computing technologies, together with the promise of flexible, cheap and efficient provision of services, has provided the opportunity to externalize such a common process, shaping what has been called Identity Management as a Service (IDaaS). Nevertheless, as in the case of other cloud-based services, IDaaS brings with it great concerns regarding security and privacy, such as the loss of control over the outsourced data. In this paper we analyze these concerns and propose BlindIdM, a model for privacy-preserving IDaaS with a focus on data privacy protection. In particular, we describe how a SAML-based system can be augmented to employ proxy re-encryption techniques for achieving data condentiality with respect to the cloud provider, while preserving the ability to supply the identity service. This is an innovative contribution to both the privacy and identity management landscapes.
Computer Standards & Interfaces, Special Issue on Security in Information Systems, vol. 36, issue 4, Elsevier, pp. 792-800, 2014. DOI (I.F.: 0.879)
Trust is an essential feature of any system where entities have to collaborate among them. Trust can assist entities making decisions about what is the best entity for establishing a certain collaboration. It would be desirable to simulate behaviour of users as in social environments where they tend to establish relationships or to trust users who have common interests or share some of their opinions, i.e., users who are similar to them to some extent. Thus, in this paper we first introduce the concept of context similarity among entities and from it we derive a similarity network which can be seen as a graph. Based on this similarity network we dene a trust model that allows us also to establish trust along a path of entities. A possible applications of our model are proximity-based trust establishment. We validate our model in this scenario.
IEEE Transactions on Information Forensics & Security, vol. 15, IEEE, pp. 3325-3334, 17/04/2020. DOI (I.F.: 7.178)
One of the biggest challenges in IoT-forensics is the analysis and correlation of heterogeneous digital evidence, to enable an effective understanding of complex scenarios. This paper defines a methodology for extracting unique objects (e.g., representing users or devices) from the files of a case, defining the context of the digital investigation and increasing the knowledge progressively, using additional files from the case (e.g. network captures). The solution includes external searches using open source intelligence (OSINT) sources when needed. In order to illustrate this approach, the proposed methodology is implemented in the JSON Users and Devices analysis (JUDAS) tool, which is able to generate the context from JSON files, complete it, and show the whole context using dynamic graphs. The approach is validated using the files in an IoT-Forensic digital investigation where an important set of potential digital evidence extracted from Amazon’s Alexa Cloud is analysed.
Journal of Parallel and Distributed Computing, vol. 144, Elsevier, pp. 124-135, 06/2020. (I.F.: 3.734)
IEEE Transactions on Vehicular Technology, vol. 70, no. 5, IEEE, pp. 4001 - 4010, 05/2021. DOI (I.F.: 5.978)
New mobility paradigms have appeared in recent years, and everything suggests that some more are coming. This fact makes apparent the necessity of modernizing the road infrastructure, the signalling elements and the traffic management systems. Many initiatives have emerged around the term Intelligent Transport System (ITS) in order to define new scenarios and requirements for this kind of applications. We even have two main competing technologies for implementing Vehicular communication protocols (V2X), C-V2X and 802.11p, but neither of them is widely deployed yet.
One of the main barriers for the massive adoption of those technologies is governance. Current solutions rely on the use of a public key infrastructure that enables secure collaboration between the different entities in the V2X ecosystem, but given its global scope, managing such infrastructure requires reaching agreements between many parties, with conflicts of interest between automakers and telecommunication operators. As a result, there are plenty of use cases available and two mature communication technologies, but the complexity at the business layer is stopping the drivers from taking advantage of ITS applications.
Blockchain technologies are defining a new decentralized paradigm for most traditional applications, where smart contracts provide a straightforward mechanism for decentralized governance. In this work, we propose an approach for decentralized V2X (D-V2X) that does not require any trusted authority and can be implemented on top of any communication protocol. We also define a proof-of-concept technical architecture on top of a cheap and highly secure System-on-Chip (SoC) that could allow for massive adoption of D-V2X.