Una pretensión desmedida, pero necesaria

Presentación del número 11 de la revista Renglones con el tema de Cultura. La cultura como concepto ha sido estudiada desde diferentes enfoques, ramas del saber o tradiciones científicas, todas contribuyendo con su propia versión de lo que es cultura. Se revisan algunas definiciones realizadas por Edward Burnet Tylor, Antonio Gramsci, Gilberto Giménez y Pierre Bourdieu. Se enfatiza en la importancia de la producción y del estudio de la cultura desde la universidad y se da una introducción a los textos presentados en esta edición

Policy administration in tag-based authorization

Tag-Based Authorization (TBA) is a hybrid access control model that combines the ease of use of extensional access control models with the expressivity of logic-based formalisms. The main limitation of TBA is that it lacks support for policy administration. More precisely, it does not allow policy-writers to specify administrative policies that constrain the tags that users can assign, and to verify the compliance of assigned tags with these policies. In this paper we introduce TBA2 (Tag-Based Authorization & Administration), an extension of TBA that enables policy administration in distributed systems. We show that TBA2 is more expressive than TBA and than two reference administrative models proposed in the literature, namely HRU and ARBAC97. © 2013 Springer-Verlag

A privacy preservation model for Facebook-style social network systems

Recent years have seen unprecedented growth in the popularity of social network systems, with Facebook being an archetypical example. The access control paradigm behind the privacy preservation mechanism of Facebook is distinctly different from such existing access control paradigms as Discretionary Access Control, Role-Based Access Control, Capability Systems, and Trust Management Systems. This work takes a first step in deepening the understanding of this access control paradigm, by proposing an access control model that formalizes and generalizes the privacy preservation mechanism of Facebook. The model can be instantiated into a family of Facebook-style social network systems, each with a recognizably different access control mechanism, so that Facebook is but one instantiation of the model. We also demonstrate that the model can be instantiated to express policies that are not currently supported by Facebook but possess rich and natural social significance. This work thus delineates the design space of privacy preservation mechanisms for Facebook-style social network systems, and lays out a formal framework for policy analysis in these systems

Goal-Oriented Access Control Model for Ambient Assisted Living

International audienceAmbient assisted living is a new interdisciplinary field aiming at supporting senior citizens in their home by means of embedded technologies. This domain offer an interesting challenge for providing dependability and security in a privacy-respecting way: in order to provide services in an emergency we cannot monitor on a second-by-second base a senior citizen. Beside being immoral, it would be illegal (at least in Europe). At the same time if we do not get notified of an emergency, the entire system would be useless. In this paper we present an access control model for this domain that extends RBAC with the notion of organizational model, goals and dependencies. In this model we can associate permission to the objectives that have been assigned to the users of the system and solve the trade-off between security and dependability