Security in Distributed, Grid, Mobile, and Pervasive Computing, Y.. Xiao Eds., Auerbach Publications, pp. 255-288, April, 2007. More.. vivas2007.pdf (321.43 KB)
11th Australasian Conference on Information Security and Privacy (ACISP’06), LNCS 4058, Springer, pp. 383-394, 2006. DOI More..
Abstract
This paper elaborates on a solution to represent authorization and delegation in a graphical way, allowing users to better interpret delegation relationships. We make use of Weighted Trust Graph (WTG) as an instrument to represent delegation and authorization, extending it to cope with more complicated concepts, and providing a graphical representation of the level of confidence that exists between two entities regarding a resource or attribute. We represent the level of confidence for each pair of entities as a point in an axis diagram, as a set of points, or as a set of triangular regions depending on the accuracy we need. Then, we use the same diagram to represent the set of acceptable confidence level, that we call authorization policy set. In this way, a single diagram can be used to decide about authorization, thus providing a powerful tool for systems in which interaction of users is needed.
ERCIM News, no. 63, ERCIM, pp. 33-34, October, 2005. More.. IsaacAgudo2005.pdf (157.48 KB)
Nuevas tendencias en gestión de redes, Novática, no. 196, CEPIS, pp. 20-25, December, 2008. More..
Abstract
En el momento que se introduce en el mercado nuevas tecnologías basadas en entornos distribuidos comienzan a surgir en paralelo nuevos problemas de seguridad en los sistemas SCADA (Supervisory Control and Data Acquisition), los cuales monitorizan y gestionan otras infraestructuras de gran complejidad y escala. Un fallo o una interrupción en uno de sus componentes podría suponer un impacto negativo sobre la funcionalidad de otras infraestructuras, por lo que se hace necesario realizar frecuentes análisis de seguridad para así mantener actualizado el conocimiento y proveer recomendaciones y/o soluciones para mitigar o evitar futuras ocurrencias, garantizando una gestión de red fiable y siempre disponible.
IV Reunión Española de Criptología (IV REC), pp. 27-33, Septiembre, 1996. More..
Abstract
Nowadays cryptography is present in nearly every aspect of our everyday life, in particular public-key cryptosystems. Some of them have a mathematical foundation of number theory working with big integer numbers. Factoring these numbers is more complex and time-consuming than generating and testing prime numbers; this is the main reason for the strenght of some public key cryptosystems. This paper presents three different probabilistic methods for testing big prime numbers in a reasonable amount of time. A comparison of their efficiency to test prime numbers is also introduced.
18th International Conference on Applied Cryptography and Network Security (ACNS’20), vol. 12147, Springer, pp. 297-320, 10/2020. DOI More.. 1840.pdf (1.48 MB)