@inproceedings {morales2022cc, title = {Real-time Crowd Counting based on Wearable Ephemeral IDs}, booktitle = {19th International Conference on Security and Cryptography (SECRYPT 2022)}, year = {2022}, month = {07/2022}, pages = {249-260}, publisher = {Scitepress}, organization = {Scitepress}, address = {Lisbon}, abstract = {Crowd Counting is a very interesting problem aiming at counting people typically based on density averages and/or aerial images. This is very useful to prevent crowd crushes, especially on urban environments with high crowd density, or to count people in public demonstrations. In addition, in the last years, it has become of paramount importance for pandemic management. For those reasons, giving users automatic mechanisms to anticipate high risk situations is essential. In this work, we analyze ID-based Crowd Counting, and propose a real-time Crowd Counting system based on the Ephemeral ID broadcast by contact tracing applications on wearable devices. We also performed some simulations that show the accuracy of our system in different situations. }, keywords = {Crowd Counting, IDS, Pandemics, privacy, Secure Multiparty computation}, isbn = {978-989-758-590-6}, issn = {2184-7711}, doi = {10.5220/0011327200003283}, author = {Daniel Morales and Isaac Agudo and Javier Lopez} } @inproceedings {1648, title = {Requisitos y soluciones de privacidad para la testificaci{\'o}n digital}, booktitle = {III Jornadas Nacionales de Investigaci{\'o}n en Ciberseguridad (JNIC 2017)}, volume = {Actas del JNIC 2017}, year = {2017}, pages = {51-58}, publisher = { Servicio de Publicaciones de la URJC}, organization = { Servicio de Publicaciones de la URJC}, address = {Madrid (Spain)}, isbn = {978-84-608-4659-8}, url = {https://eciencia.urjc.es/handle/10115/14540}, author = {Ana Nieto and Ruben Rios} } @inproceedings {430, title = {Recovery of Structural Controllability for Control Systems}, booktitle = {Eighth IFIP WG 11.10 International Conference on Critical Infrastructure Protection, SRI International, Arlington, Virginia, USA }, volume = {441}, year = {2014}, pages = {47-63}, publisher = {Springer}, organization = {Springer}, address = {Arlington, Virginia, USA}, abstract = {

Fundamental problems in control systems theory are controllability and observability, and designing control systems so that these properties are satisfied or approximated sufficiently. However, it is prudent to as- sume that an attacker will not only be able to subvert measurements but also control the system. Moreover, an advanced adversary with an understanding of the control system may seek to take over control of the entire system or parts thereof, or deny the legitimate operator this capability. The effectiveness of such attacks has been demonstrated in previous work. Indeed, these attacks cannot be ruled out given the likely existence of unknown vulnerabilities, increasing connectivity of nominally air-gapped systems and supply chain issues. The ability to rapidly recover control after an attack has been initiated and to detect an adversary{\textquoteright}s presence is, therefore, critical. This paper focuses on the problem of structural controllability, which has recently attracted substantial attention through the equivalent problem of the power dom- inating set introduced in the context of electrical power network control. However, these problems are known to be NP-hard with poor approx- imability. Given their relevance to many networks, especially power networks, this paper studies strategies for the efficient restoration of controllability following attacks and attacker-defender interactions in power-law networks.\ 

}, keywords = {Control systems, power domination, resilience, structural controllability}, isbn = {978-3-662-45354-4}, issn = {1868-4238}, doi = {http://dx.doi.org/10.1007/978-3-662-45355-1_4}, author = {Cristina Alcaraz and Stephen Wolthusen} } @inproceedings {Rios2012d, title = {Robust Probabilistic Fake Packet Injection for Receiver-Location Privacy in WSN}, booktitle = {17th European Symposium on Research in Computer Security (ESORICS 2012)}, series = {LNCS}, volume = {7459}, year = {2012}, month = {Sep 2012}, pages = {163-180}, publisher = {Springer}, organization = {Springer}, address = {Pisa, Italy}, abstract = {

The singular communication model in wireless sensor networks (WSNs) originate pronounced traffic patterns that allow a local observer to deduce the location of the base station, which must be kept secret for both strategical and security reasons. In this work we present a new receiver-location privacy solution called HISP (Homogenous Injection for Sink Privacy). Our scheme is based on the idea of hiding the flow of real traffic by carefully injecting fake traffic to homogenize the transmissions from a node to its neighbors. This process is guided by a lightweight probabilistic approach ensuring that the adversary cannot decide with sufficient precision in which direction to move while maintaining a moderate amount of fake traffic. Our system is both validated analytically and experimentally through simulations.

}, isbn = {978-3-642-33167-1}, issn = {0302-9743}, doi = {10.1007/978-3-642-33167-1_10}, author = {Ruben Rios and Jorge Cuellar and Javier Lopez}, editor = {Sara Foresti and Moti Yung and Fabio Martinelli} } @inproceedings {rosado2009b, title = {Reusable Security Use Cases for Mobile Grid environments}, booktitle = {Workshop on Software Engineering for Secure Systems}, year = {2009}, pages = {1-8}, publisher = {IEEE}, organization = {IEEE}, address = {Vancouver, Canada}, abstract = {

Due to the growing complexity of softwaredevelopment, developing software through systematicprocesses is becoming more and more important.Likewise, it is important that the development processused integrates security aspects from the first stages atthe same level as other functional and non-functionalrequirements. In the last years, GRID technology hasshown to be the most important one and it allows us tobuild very complex information systems with differentand remarkable features (interoperability betweenmultiple security domains, cross-domainauthentication and authorization, dynamic,heterogeneous and limited mobile devices, etc).Traditionally, systems based on GRID Computing havenot been developed through adequate methodologiesand have not taken into account security requirementsthroughout their development, only offering securitytechnical solutions at the implementation stages. Thispaper shows part of a development methodology thatwe are elaborating for the construction of informationsystems based on Grid Computing highly dependent onmobile devices where security plays a very importantrole. Specifically, in this paper, we will present theanalysis phase, managed by reusable use casesthrough which we can define the requirements andneeds of these systems obtaining an analysis modelthat can be used as input to the following phase of themethodology, the design phase of mobile Grid systems.

}, isbn = {978-1-4244-3725-2}, author = {David G. Rosado and Eduardo Fernandez-Medina and Javier Lopez} } @inproceedings {rosado2009a, title = {Reutilizaci{\'o}n de Casos de Uso en el Desarrollo de Sistemas Grid seguros}, booktitle = {XII Conferencia Iberoamericana de Ingenier{\'\i}a de Requisitos y Ambientes de Software (IDEAS{\textquoteright}09)}, year = {2009}, pages = {388-393}, publisher = {University of Colombia}, organization = {University of Colombia}, address = {Medell{\'\i}n, Colombia}, abstract = {

El desarrollo software debe estar basado en un proceso sistem{\'a}tico y estructurado donde se definan los m{\'e}todos y t{\'e}cnicas a utilizar en todo su ciclo de vida, ayudando as{\'\i} a obtener un producto de calidad. Es igualmente importante que el proceso sistem{\'a}tico considere aspectos de seguridad desde las primeras etapas, integr{\'a}ndola como un elemento m{\'a}s en el ciclo de desarrollo. En este art{\'\i}culo mostramos la metodolog{\'\i}a de desarrollo sistem{\'a}tico que sirve de gu{\'\i}a para el desarrollo de cualquier sistema Grid con dispositivos m{\'o}viles, considerando la seguridad durante todas las fases de desarrollo, lo que nos permitir{\'a} obtener como resultado sistemas Grid seguros, robustos y escalables. Este art{\'\i}culo presenta la fase de an{\'a}lisis, dirigida por casos de uso reutilizables, mediante los cuales se definen los requisitos y necesidades de estos sistemas, y es aplicada a un caso de estudio real de un Grid para el acceso de contenidos multimedia en un contexto period{\'\i}stico.

}, isbn = {978-958-44-5028-9}, author = {David G. Rosado and Eduardo Fernandez-Medina and Javier Lopez} } @inproceedings {IsaacAgudo2005b, title = {A Representation Model of Trust Relationships with Delegation Extensions}, booktitle = {3th International Conference on Trust Management (iTRUST{\textquoteright}05)}, series = {LNCS}, volume = {3477}, year = {2005}, month = {May}, pages = {9-22}, publisher = {Springer}, organization = {Springer}, address = {Versailles, France}, abstract = {

Logic languages establish a formal framework to solve authorization and delegation conflicts. However, we consider that a visual representation is necessary since graphs are more expressive and understandable than logic languages. In this paper, and after overviewing previous works using logic languages, we present a proposal for graph representation of authorization and delegation statements. Our proposal is based on Varadharajan et al. solution, though improve several elements of that work. We also discuss about the possible implementation of our proposal using attribute certificates.

}, isbn = {978-3-540-26042-4}, issn = {0302-9743 (Print) 1611-3349 (Online)}, doi = {10.1007/11429760_9}, author = {Isaac Agudo and Javier Lopez and Jose A. Montenegro} }