@article {Alcaraz2023a, title = {Protecting Digital Twin Networks for 6G-enabled Industry 5.0 Ecosystems}, journal = {IEEE Network Magazine}, year = {In Press}, publisher = {IEEE}, issn = {0890-8044}, author = {Cristina Alcaraz and Javier Lopez} } @incollection {2013, title = {POM: A Trust-based AHP-like Methodology to Solve Conflict Requirements for the IoT}, booktitle = {Collaborative Approaches for Cyber Security in Cyber-Physical Systems}, number = {Part of the Advanced Sciences and Technologies for Security Applications book series (ASTSA)}, year = {2023}, month = {01/2023}, pages = {145-170}, publisher = {Springer}, organization = {Springer}, keywords = {Analytic Hierarchy Process (AHP), Internet of Things (IoT), Multi Criteria Decision Analysis (MCDA), Requirements Engineering, Trust}, issn = {1613-5113}, doi = {https://doi.org/10.1007/978-3-031-16088-2_7}, url = {https://link.springer.com/chapter/10.1007/978-3-031-16088-2_7}, author = {Davide Ferraris and Carmen Fernandez-Gago and Javier Lopez} } @article {morales2023psi, title = {Private set intersection: A systematic literature review}, journal = {Computer Science Review}, volume = {49}, number = {100567}, year = {2023}, month = {05/2023}, publisher = {Elsevier}, type = {Review}, address = {ScienceDirect}, abstract = {Secure Multi-party Computation (SMPC) is a family of protocols which allow some parties to compute a function on their private inputs, obtaining the output at the end and nothing more. In this work, we focus on a particular SMPC problem named Private Set Intersection (PSI). The challenge in PSI is how two or more parties can compute the intersection of their private input sets, while the elements that are not in the intersection remain private. This problem has attracted the attention of many researchers because of its wide variety of applications, contributing to the proliferation of many different approaches. Despite that, current PSI protocols still require heavy cryptographic assumptions that may be unrealistic in some scenarios. In this paper, we perform a Systematic Literature Review of PSI solutions, with the objective of analyzing the main scenarios where PSI has been studied and giving the reader a general taxonomy of the problem together with a general understanding of the most common tools used to solve it. We also analyze the performance using different metrics, trying to determine if PSI is mature enough to be used in realistic scenarios, identifying the pros and cons of each protocol and the remaining open problems.}, keywords = {privacy, Private set intersection, Secure Multiparty computation, security}, issn = {1574-0137}, doi = {https://doi.org/10.1016/j.cosrev.2023.100567}, url = {https://www.sciencedirect.com/science/article/pii/S1574013723000345}, author = {Daniel Morales and Isaac Agudo and Javier Lopez} } @article {rios2022pmec, title = {Personal IoT Privacy Control at the Edge}, journal = {IEEE Security \& Privacy }, volume = {20}, year = {2022}, month = {01/2022}, pages = {23 - 32}, publisher = {IEEE}, abstract = {

This article introduces a privacy manager for IoT data based on Edge Computing. This poses the advantage that privacy is enforced before data leaves the control of the user, who is provided with a tool to express data sharing preferences based on a novel context-aware privacy language.

}, issn = {1540-7993}, doi = {10.1109/MSEC.2021.3101865}, author = {Ruben Rios and Jose A. Onieva and Rodrigo Roman and Javier Lopez} } @inproceedings {1979, title = {Privacidad Contextual en entornos Edge}, booktitle = {VII Jornadas Nacionales de Investigaci{\'o}n en Ciberseguridad (JNIC 2022)}, year = {2022}, month = {06/2022}, pages = {122-129}, address = {Bilbao, Spain}, abstract = {

La privacidad contextual se refiere a la protecci{\'o}n de toda aquella informaci{\'o}n que puede desprenderse de la interacci{\'o}n entre usuarios y/o servicios, exceptuando los datos que el propio usuario elige transmitir. La localizaci{\'o}n, el tiempo, los patrones de uso y los diferentes par{\'a}metros necesarios para realizar la comunicaci{\'o}n son algunos ejemplos. Este tipo de privacidad es extremadamente importante en la computaci{\'o}n edge debido al acercamiento de los recursos de la infraestructura a los usuarios. Por ello, el objetivo de este trabajo es ofrecer un an{\'a}lisis y clasificaci{\'o}n de las diferentes soluciones propuestas en la literatura respecto a la privacidad contextual en entornos edge, mostrando tanto las capacidades de los mecanismos actuales como los desaf{\'\i}os en este campo.

}, keywords = {Computaci{\'o}n edge, Privacidad, Privacidad contextual}, isbn = {978-84-88734-13-6 }, author = {Manuel Ruiz and Ruben Rios and Rodrigo Roman and Javier Lopez} } @incollection {1777, title = {Privacy-Aware Digital Forensics}, booktitle = {Security and Privacy for Big Data, Cloud Computing and Applications}, year = {2019}, month = {09/2019}, publisher = {The Institution of Engineering and Technology (IET) }, organization = {The Institution of Engineering and Technology (IET) }, edition = {Lizhe Wang, Wei Ren, Raymoond Choo and Fatos Xhafa}, address = {United Kingdom}, isbn = {978-1-78561-747-8}, url = {https://www.amazon.es/Security-Privacy-Computing-Applications-Networks/dp/1785617478}, author = {Ana Nieto and Ruben Rios and Javier Lopez} } @inproceedings {kolar2018, title = {Policy Languages and Their Suitability for Trust Negotiation}, booktitle = {32nd Annual IFIP WG 11.3 Conference on Data and Applications Security and Privacy XXXII, 2018}, volume = {10980}, year = {2018}, month = {07/2018}, pages = {69-84}, publisher = {Springer, Cham}, organization = {Springer, Cham}, address = {Bergamo, Italy}, abstract = {

Entities, such as people, companies, institutions, authorities and web sites live and exist in a conjoined world. In order to live and enjoy social benefits, entities need to share knowledge, resources and to cooperate together. The cooperation brings with it many new challenges and problems, among which one is the problem of trust. This area is also important for the Computer Science. When unfamiliar entities wish to cooperate, they do not know what to expect nor whether they can trust each other. Trust negotiation solves this problem by sequential exchanging credentials between entities, which have decided to establish a trust relationship in order to reach a common goal. Entities specify their own policies that handle a disclosure of confidential information to maintain their security and privacy. Policies are defined by means of a policy language. This paper aims to identify the most suitable policy language for trust negotiation. To do so, policy languages are analysed against a set of criteria for trust negotiation that are first established.

}, isbn = {978-3-319-95728-9}, doi = {10.1007/978-3-319-95729-6_5}, url = {https://link.springer.com/chapter/10.1007/978-3-319-95729-6_5}, author = {Martin Kolar and Carmen Fernandez-Gago and Javier Lopez} } @inproceedings {RubioAlcarazLopez2017ESORICS, title = {Preventing Advanced Persistent Threats in Complex Control Networks}, booktitle = {European Symposium on Research in Computer Security}, volume = {10493}, year = {2017}, month = {09/2017}, pages = {402-418}, publisher = {22nd European Symposium on Research in Computer Security (ESORICS 2017)}, organization = {22nd European Symposium on Research in Computer Security (ESORICS 2017)}, author = {Juan E. Rubio and Cristina Alcaraz and Javier Lopez} } @inproceedings {1655, title = {PRoFIT: modelo forense-IoT con integraci{\'o}n de requisitos de privacidad}, booktitle = {XIII Jornadas de Ingenier{\'\i}a Telem{\'a}tica (JITEL 2017)}, volume = {Libro de actas}, year = {2017}, month = {01/2018}, pages = {302-309}, publisher = {Editorial Universitat Polit{\`e}cnica de Val{\`e}ncia}, organization = {Editorial Universitat Polit{\`e}cnica de Val{\`e}ncia}, address = {Valencia}, isbn = {978-84-9048-595-8}, doi = {http://dx.doi.org/10.4995/JITEL2017.2017.7061}, url = {http://jlloret.webs.upv.es/jitel2017/files/ACTASJITEL2017.pdf}, author = {Ana Nieto and Ruben Rios and Javier Lopez} } @article {lopez2017ecn, title = {Protecting Industry 4.0 against Advanced Persistent Threats}, journal = {European CIIP Newsletter}, volume = {11}, number = {1}, year = {2017}, month = {03/2017}, pages = {27-29}, publisher = {European CIIP Newsletter}, issn = {NONE}, author = {Javier Lopez and Cristina Alcaraz and Jes{\'u}s Rodriguez and Rodrigo Roman and Juan E. Rubio} } @article {nunez2017proxy, title = {Proxy Re-Encryption: Analysis of Constructions and its Application to Secure Access Delegation}, journal = {Journal of Network and Computer Applications}, volume = {87}, year = {2017}, month = {06/2017}, pages = {193-209}, publisher = {Elsevier}, abstract = {

This paper analyzes the secure access delegation problem, which occurs naturally in the cloud, and postulate that Proxy Re-Encryption is a feasible cryptographic solution, both from the functional and efficiency perspectives. Proxy re-encryption is a special type of public-key encryption that permits a proxy to transform ciphertexts from one public key to another, without the proxy being able to learn any information about the original message. Thus, it serves as a means for delegating decryption rights, opening up many possible applications that require of delegated access to encrypted data. In particular, sharing information in the cloud is a prime example. In this paper, we review the main proxy re-encryption schemes so far, and provide a detailed analysis of their characteristics. Additionally, we also study the efficiency of selected schemes, both theoretically and empirically, based on our own implementation. Finally, we discuss some applications of proxy re-encryption, with a focus on secure access delegation in the cloud.\ 

}, issn = {1084-8045}, doi = {10.1016/j.jnca.2017.03.005}, author = {David Nu{\~n}ez and Isaac Agudo and Javier Lopez} } @article {alcaraz2016POL, title = {Policy Enforcement System for Secure Interoperable Control in Distributed Smart Grid Systems}, journal = {Journal of Network and Computer Applications}, volume = {59}, year = {2016}, month = {01/2016}, pages = {301{\textendash}314}, publisher = {Elsevier}, abstract = {

Interoperability of distributed systems in charge of monitoring and maintaining the different critical domains belonging to Smart Grid scenarios comprise the central topic of this paper. Transparency in control transactions under a secure and reliable architecture is the aim of the policy enforcement system proposed here. The approach is based on the degree of observation of a context and on the role-based access control model defined by the IEC-62351-8 standard. Only authenticated and authorised entities are able to take control of those distributed elements (e.g., IEC-61850 objects) located at distant geographical locations and close to the critical infrastructures (e.g., substations). To ensure the effectiveness of the approach, it is built on graphical-theoretical formulations corresponding to graph theory, where it is possible to illustrate power control networks through power-law distributions whose monitoring relies on structural controllability theory. The interconnection of these distributions is subject to a network architecture based on the concept of the supernode where the interoperability depends on a simple rule-based expert system. This expert system focuses not only on accepting or denying access, but also on providing the means to attend to extreme situations, avoiding, as much as possible, the overloading of the communication. Through one practical study we also show the functionalities of the approach and the benefits that the authorisation itself can bring to the interoperability.\ 

}, issn = {1084-8045}, author = {Cristina Alcaraz and Javier Lopez and Stephen Wolthusen} } @inproceedings {rios2016b, title = {Privacy-Aware Trust Negotiation}, booktitle = {12th International Workshop on Security and Trust Management (STM)}, volume = {LNCS 9871}, year = {2016}, month = {09/2016}, pages = {98-105}, publisher = {Springer}, organization = {Springer}, address = {Heraklion, Crete, Greece}, abstract = {

Software engineering and information security have traditionally followed divergent paths but lately some efforts have been made to consider security from the early phases of the Software Development Life Cycle (SDLC). This paper follows this line and concentrates on the incorporation of trust negotiations during the requirements engineering phase. More precisely, we provide an extension to the SI* modelling language, which is further formalised using answer set programming specifications to support the automatic verification of the model and the detection of privacy conflicts caused by trust negotiations.

}, keywords = {Goal-Oriented Modelling, privacy, Requirements Engineering, Secure Software Engineering, Trust}, isbn = {978-3-319-46597-5}, issn = {0302-9743}, doi = {10.1007/978-3-319-46598-2 7}, url = {http://link.springer.com/chapter/10.1007/978-3-319-46598-2_7}, author = {Ruben Rios and Carmen Fernandez-Gago and Javier Lopez} } @inproceedings {nunez2015parametric, title = {A Parametric Family of Attack Models for Proxy Re-Encryption}, booktitle = {28th IEEE Computer Security Foundations Symposium}, series = {CSF{\textquoteright}15}, year = {2015}, month = {07/2015}, pages = {290-301}, publisher = {IEEE Computer Society}, organization = {IEEE Computer Society}, address = {Verona, Italy}, abstract = {

Proxy Re-Encryption (PRE) is a type of Public-Key Encryption (PKE) which provides an additional re-encryption functionality. Although PRE is inherently more complex than PKE, attack models for PRE have not been developed further than those inherited from PKE. In this paper we address this gap and define a parametric family of attack models for PRE, based on the availability of both the decryption and re-encryption oracles during the security game. This family enables the definition of a set of intermediate security notions for PRE that ranges from {\textquoteleft}{\textquoteleft}plain{\textquoteright}{\textquoteright} IND-CPA to {\textquoteleft}{\textquoteleft}full{\textquoteright}{\textquoteright} IND-CCA. We analyze some relations among these notions of security, and in particular, the separations that arise when the re-encryption oracle leaks re-encryption keys. In addition, we discuss which of these security notions represent meaningful adversarial models for PRE. Finally, we provide an example of a recent {\textquoteleft}{\textquoteleft}CCA1- secure{\textquoteright}{\textquoteright} scheme from PKC 2014 whose security model does not capture chosen-ciphertext attacks through re-encryption and for which we describe an attack under a more realistic security notion. This attack emphasizes the fact that PRE schemes that leak re-encryption keys cannot achieve strong security notions.

}, isbn = { 978-1-4673-7538-2}, issn = {1063-6900}, doi = {10.1109/CSF.2015.27}, author = {David Nu{\~n}ez and Isaac Agudo and Javier Lopez} } @incollection {nunez15privacy, title = {Privacy-Preserving Identity Management as a Service}, booktitle = {Accountability and Security in the Cloud}, series = {Lecture Notes in Computer Science}, volume = {8937}, year = {2015}, pages = {114-125}, publisher = {Springer International Publishing}, organization = {Springer International Publishing}, abstract = {

In this paper we tackle the problem of privacy and confidentiality in Identity Management as a Service (IDaaS). The adoption of cloud computing technologies by organizations has fostered the externalization of the identity management processes, shaping the concept of Identity Management as a Service. However, as it has happened to other cloud-based services, the cloud poses serious risks to the users, since they lose the control over their data. As part of this work, we analyze these concerns and present a model for privacy-preserving IDaaS, called BlindIdM, which is designed to provide data privacy protection through the use of cryptographic safeguards.

}, keywords = {Cloud Computing, Cryptography, Identity Management as a Service, privacy}, isbn = {978-3-319-17198-2}, doi = {10.1007/978-3-319-17199-9_5}, url = {http://dx.doi.org/10.1007/978-3-319-17199-9_5}, author = {David Nu{\~n}ez and Isaac Agudo and Javier Lopez}, editor = {Massimo Felici and Carmen Fernandez-Gago} } @article {rios2015, title = {Probabilistic receiver-location privacy protection in wireless sensor networks}, journal = {Information Sciences}, volume = {321}, year = {2015}, month = {07/2015}, pages = {205 - 223}, publisher = {Elsevier}, abstract = {

Wireless sensor networks (WSNs) are continually exposed to many types of attacks. Among these, the attacks targeted at the base station are the most devastating ones since this essential device processes and analyses all traffic generated in the network. Moreover, this feature can be exploited by a passive adversary to determine its location based on traffic analysis. This receiver-location privacy problem can be reduced by altering the traffic pattern of the network but the adversary may still be able to reach the base station if he gains access to the routing tables of a number of sensor nodes. In this paper we present HISP-NC (Homogenous Injection for Sink Privacy with Node Compromise protection), a receiver-location privacy solution that consists of two complementary schemes which protect the location of the base station in the presence of traffic analysis and node compromise attacks. The HISP-NC data transmission protocol prevents traffic analysis by probabilistically hiding the flow of real traffic with moderate amounts of fake traffic. Moreover, HISP-NC includes a perturbation mechanism that modifies the routing tables of the nodes to introduce some level of uncertainty in attackers capable of retrieving the routing information from the nodes. Our scheme is validated both analytically and experimentally through extensive simulations.

}, keywords = {node capture, privacy, security, traffic analysis, wireless sensor networks}, issn = {0020-0255}, doi = {10.1016/j.ins.2015.01.016}, author = {Ruben Rios and Jorge Cuellar and Javier Lopez} } @article {MoLo15, title = {A practical solution for sealed bid and multi-currency auctions}, journal = {Computers \& Security}, volume = {45}, year = {2014}, month = {09/2014}, pages = {186-198}, publisher = {Elsevier}, abstract = {
This paper introduces a sealed bid and multi-currency auction using secure multiparty computation (SMC). 
Two boolean functions, a comparison and multiplication function, have been designed as required to apply SMC. These functions are applied without revealing any information, not even to trusted third parties such as the auctioneer. A type of Zero Knowledge proof, discreet proof, has been implemented with three variants, interactive, regular and reduced non interactive proofs. These proofs make it possible to verify the correctness of the functions whilst preserving the privacy of the bid values. Moreover, a system performance evaluation of the proposal has been realized on heterogeneous platforms, including a mobile platform. The evaluation concludes that our proposal is practical even on mobile platforms.
}, keywords = {Multi-currency auctions, proof certification, Sealed auctions, Secure Multiparty computation, Zero Knowledge Protocols}, issn = {0167-4048}, doi = {10.1016/j.cose.2014.06.004}, author = {Jose A. Montenegro and Javier Lopez} } @inproceedings {Lopez2014prl, title = {Preserving Receiver-Location Privacy in Wireless Sensor Networks}, booktitle = {Information Security Practice and Experience (ISPEC 2014)}, volume = {8434}, year = {2014}, month = {05/2014}, pages = {15-27}, publisher = {Springer}, organization = {Springer}, address = {Fuzhou, China}, abstract = {

Wireless sensor networks (WSNs) are exposed to many different types of attacks. Among these, the most devastating attack is to compromise or destroy the base station since all communications are addressed exclusively to it. Moreover, this feature can be exploited by a passive adversary to determine the location of this critical device. This receiver-location privacy problem can be reduced by hindering traffic analysis but the adversary may still obtain location information by capturing a subset of sensor nodes in the field. This paper addresses, for the first time, these two problems together in a single solution

}, keywords = {Location Privacy, node capture, traffic analysis, wireless sensor networks}, isbn = {978-3-319-06319-5}, issn = {0302-9743}, doi = {10.1007/978-3-319-06320-1_3}, url = {http://link.springer.com/chapter/10.1007/978-3-319-06320-1_3$\#$}, author = {Javier Lopez and Ruben Rios and Jorge Cuellar} } @article {agudo2013, title = {A Privacy-Aware Continuous Authentication Scheme for Proximity-Based Access Control}, journal = {Computers \& Security}, volume = {39 (B)}, year = {2013}, month = {11/2013}, pages = {117-126}, publisher = {Elsevier}, abstract = {

Continuous authentication is mainly associated with the use of biometrics to guarantee that a resource is being accessed by the same user throughout the usage period. Wireless devices can also serve as a supporting technology for continuous authentication or even as a complete alternative to biometrics when accessing proximity-based services. In this paper we present the implementation of a secure, non-invasive continuous authentication scheme supported by the use of Wearable Wireless Devices (WWD), which allow users to gain access to proximity-based services while preserving their privacy. Additionally we devise an improved scheme that circumvents some of the limitations of our implementation.

}, issn = {0167-4048}, doi = {10.1016/j.cose.2013.05.004}, author = {Isaac Agudo and Ruben Rios and Javier Lopez} } @proceedings {1832, title = {Proceedings of the 10th International Conference on Trust, Privacy, and Security in Digital Business (TRUSTBUS 2013)}, journal = {10th International Conference on Trust, Privacy and Security in Digital Business (TRUSTBUS 2013)}, volume = {LNCS 8058}, year = {2013}, month = {Aug 2013}, publisher = {Springer}, address = {Prague, Czech Republic}, isbn = {978-3-642-40342-2}, editor = {Steve Furnell and Costas Lambrinoudakis and Javier Lopez} } @proceedings {1782, title = {Proceedings of the 7th International Conference on Critical Information Infrastructures Security (CRITIS 2012)}, journal = {7th International Conference on Critical Information Infrastructures Security (CRITIS 2012)}, volume = {LNCS 7722}, year = {2013}, month = {2013}, publisher = {Springer}, address = {Lillehammer (Norway)}, isbn = {978-3-642-41485-5 }, url = {http://link.springer.com/book/10.1007\%2F978-3-642-41485-5}, editor = {B. Hammerli and N. Svendsen and Javier Lopez} } @proceedings {1792, title = {Proceedings of the 7th International Conference on Network and System Security (NSS 2013)}, volume = {LNCS}, number = {7873}, year = {2013}, month = {Jun 2013}, publisher = {Springer}, isbn = {978-3-642-38631-2}, url = {http://www.springer.com/computer/security+and+cryptology/book/978-3-642-38630-5}, editor = {Javier Lopez and Xinyi Huang and Ravi Sandhu} } @proceedings {1783, title = {Proceedings of the 3rd International ACMSigsoft Symposium on Architecting Critical Systems (ISARCS 2012)}, journal = {3rd International ACMSigsoft Symposium on Architecting Critical Systems (ISARCS 2012)}, year = {2012}, month = {Jun 2012}, publisher = {ACM}, address = {Bertinoro (Italy)}, editor = {Jorge Cuellar and Javier Lopez} } @proceedings {1781, title = {Proceedings of the 4th International Symposium on Cyberspace Safety and Security (CSS 2012)}, journal = {4th International Symposium on Cyberspace Safety and Security (CSS 2012)}, volume = {LNCS}, year = {2012}, month = {Dec 2012}, publisher = {Springer}, address = {Melbourne (Australia)}, issn = {978-3-642-35362-8}, editor = {Y. Xiang and Javier Lopez and C. Kuo and W. Zhou} } @article {JordiForne2009, title = {Pervasive Authentication and Authorization Infrastructures for Mobile Users}, journal = {Computer and Security}, volume = {29}, year = {2010}, pages = {501-514}, publisher = {elsevier}, abstract = {

Network and device heterogeneity, nomadic mobility, intermittent connectivity and, more generally, extremely dynamic operating conditions, are major challenges in the design of security infrastructures for pervasive computing. Yet, in a ubiquitous computing environment, limitations of traditional solutions for authentication and authorization can be overcome with a pervasive public key infrastructure (pervasive-PKI). This choice allows the validation of credentials of users roaming between heterogeneous networks, even when global connectivity is lost and some services are temporarily unreachable. Proof-of-concept implementations and testbed validation results demonstrate that strong security can be achieved for users and applications through the combination of traditional PKI services with a number of enhancements like: (i) dynamic and collaborative trust model, (ii) use of attribute certificates for privilege management, and (iii) modular architecture enabling nomadic mobility and enhanced with reconfiguration capabilities.

}, issn = {0167-4048}, doi = {10.1016/j.cose.2009.09.001}, author = {Jordi Forne and Francisca Hinajeros and Andres Marin and Florina Almenarez and Javier Lopez and Jose A. Montenegro and Marc Lacoste and Daniel Diaz} } @proceedings {1784, title = {Proceeding of the 3rd International Conference on Network and System Security (NSS 2009)}, journal = {3rd International Conference on Network and System Security (NSS 2009)}, year = {2009}, month = {OCT 2009}, publisher = {IEEE Computer Sociaty}, address = {Gold Coast, Australia}, isbn = {978-07695-3838-9}, editor = {X. Xiang and Javier Lopez and H. Wang and W. Zhou} } @inproceedings {rosado2008, title = {PSecGCM: Process for the development of Secure Grid Computing based Systems with Mobile devices}, booktitle = {International Conference on Availability, Reliability and Security (ARES{\textquoteright}08)}, year = {2008}, pages = {136-143}, publisher = {IEEE Computer Society}, organization = {IEEE Computer Society}, address = {A Grid computing system is defined as a platform that supports distributed system applications which require fast access to a large quantity of distributed resources in a coordinated manner. With the development of wireless technology and mobile devices,}, abstract = {

A Grid computing system is defined as a platformthat supports distributed system applications which require fastaccess to a large quantity of distributed resources in acoordinated manner. With the development of wirelesstechnology and mobile devices, the Grid becomes the perfectcandidate so that mobile users can make complex works that addnew computational capacity to the Grid. Security of thesesystems, due to their distributed and open nature, receives greatinterest. The growing size and profile of the grid requirecomprehensive security solutions as they are critical to thesuccess of the endeavour. A formal approach to security in thesoftware life cycle is essential to protect corporate resources.However, little thought has been given to this aspect of softwaredevelopment. Due to its criticality, security should be integratedas a formal approach in the software life cycle. A methodology ofdevelopment for secure mobile Grid computing based systems isdefined, that is to say, an engineering process that defines thesteps to follow so that starting from the necessities to solve, wecan design and construct a secure Grid system with support formobile devices that is able to solve and cover these necessities.

}, issn = {978-0-7695-3102-1}, author = {David G. Rosado and Eduardo Fernandez-Medina and Javier Lopez and Mario Piattini} } @incollection {Lopez2007, title = {On the Protection and Technologies of Critical Information Infrastructures.}, booktitle = {On Foundations of Security Analysis and Design IV, FOSAD 2006/2007, Springer}, series = {LNCS}, volume = {4677}, year = {2007}, note = {

10.1007/978-3-540-74810-6_6

}, pages = {160-182}, abstract = {

Critical Infrastructures are complex and highly interconnected systems that are crucial for the well-being of the society. Any type of failure can cause significant damage, affecting one or more sectors due to their inherent interdependency. Not only the infrastructures are critical, but also the information infrastructures that manage, control and supervise them. Due to the seriousness of the consequences, the protection of these critical (information) infrastructures must have the highest priority. It is the purpose of this book chapter to review and discuss about these infrastructures, to explain their elements, and to highlight their research and development issues. This chapter will also discuss the role of Wireless Sensor Network (WSN) technology in the protection of these infrastructures.

}, keywords = {Critical Information Infrastructure Protection, wireless sensor networks}, issn = {0302-9743}, doi = {10.1007/978-3-540-74810-6_6}, url = {http://dx.doi.org/10.1007/978-3-540-74810-6_6}, author = {Javier Lopez and Cristina Alcaraz and Rodrigo Roman} } @proceedings {1609, title = {Public Key Infrastructure, 4th European PKI Workshop: Theory and Practice, EuroPKI 2007, Palma de Mallorca, Spain, June 28-30, 2007, Proceedings}, journal = {EuroPKI}, volume = {4582}, year = {2007}, publisher = {Springer}, isbn = {978-3-540-73407-9}, editor = {Javier Lopez and Pierangela Samarati and Josep L. Ferrer} } @inproceedings {IsaacAgudo2006a, title = {Pol{\'\i}ticas de delegaci{\'o}n para credenciales ponderadas y su representaci{\'o}n gr{\'a}fica}, booktitle = {IX Reuni{\'o}n Espa{\~n}ola sobre Criptolog{\'\i}a y Seguridad de la informaci{\'o}n (RECSI{\textquoteright}06)}, year = {2006}, month = {Septiembre}, pages = {311-322}, address = {Barcelona, Spain}, isbn = {84-9788-502-3}, author = {Isaac Agudo and Javier Lopez and Jose A. Montenegro} } @inproceedings {AntonioMunoz2005a, title = {Perfiles Seguros para Comercio Movil}, booktitle = {III Simposio Espa{\~n}ol de Comercio Electronico (SCE{\textquoteright}05)}, year = {2005}, pages = {235-244}, publisher = {Universitat de les Illes Balears}, organization = {Universitat de les Illes Balears}, abstract = {

Los escenarios de comercio m{\'o}vil existentes en la actualidad presentan muchas deficiencias. La mayor{\'\i}a de estos escenarios, como no podr{\'\i}a ser de otra forma, tienen en cuenta aspectos relativos a la seguridad, prestando especial atenci{\'o}n a las propiedades de Autenticaci{\'o}n y Autorizaci{\'o}n. De entre los elementos esenciales que se utilizan para proporcionar estos servicios de seguridad, los perfiles son un elemento com{\'u}n que permiten la personalizaci{\'o}n de los servicios del usuario m{\'o}vil. Sin embargo, los perfiles tambi{\'e}n precisan de una administraci{\'o}n segura. En este trabajo presentamos unas consideraciones iniciales respecto a los distintos tipos de perfiles, sus niveles de seguridad para cada tipo, as{\'\i} como indicaciones para el almacenamiento de manera segura. Por lo tanto, analizaremos las distintas alternativas como medio de almacenamiento, discuti{\'e}ndolas y prestando especial atenci{\'o}n a las tarjetas inteligentes.

}, author = {Mu{\~n}oz, Antonio and Jose A. Onieva and Javier Lopez} } @inproceedings {Roman2005a, title = {Protecci{\'o}n contra el Spam Utilizando Desaf{\'\i}os a Priori}, booktitle = {V Jornadas de Ingenier{\'\i}a Telem{\'a}tica (JITEL{\textquoteright}05)}, year = {2005}, month = {September}, pages = {375-382}, address = {Vigo (Spain)}, abstract = {

Spam is considered to be one of the biggest problems in messaging systems. In the area of email Spam, A high number of anti-spam schemes have been proposed and deployed, but the problem has yet been well addressed. In this paper, we introduce a new scheme, called pre-challenge scheme, which avoids problems that exists in other schemes such as delay of service and denial of service. Some new mechanisms are employed to reach a good balance between security against Spam and convenience to email users. In addition, our scheme can be used for protecting other types of messaging systems, such as Instant Messaging (IM) and Blogs, against Spam.

}, author = {Rodrigo Roman and Javier Lopez and Jianying Zhou} } @inproceedings {Roman2005d, title = {Protection Against Spam using Pre-Challenges}, booktitle = {20th IFIP International Information Security Conference (IFIP-SEC{\textquoteright}05)}, year = {2005}, month = {May}, pages = {281-294}, publisher = {Springer}, organization = {Springer}, address = {Chiba (Japan)}, abstract = {

Spam turns out to be an increasingly serious problem to email users. A number of anti-spam schemes have been proposed and deployed, but the problem has yet been well addressed. One of those schemes is challenge-response, in which a challenge is imposed on an email sender. However, such a scheme introduces new problems for the users, e.g., delay of service and denial of service attacks. In this paper, we introduce a pre-challenge scheme that avoids those problems. It assumes each user has a challenge that is defined by the user himself/herself and associated with his/her email address, in such a way that an email sender can simultaneously retrieve a new receiver{\textquoteright}s email address and challenge before sending an email in the first contact. Some new mechanisms are employed to reach a good balance between security against spam and convenience to email users.

}, isbn = {0-387-25658-X}, author = {Rodrigo Roman and Jianying Zhou and Javier Lopez}, editor = {Ry{\^o}ichi Sasaki and Sihan Qing and Eiji Okamoto and Hiroshi Yoshiura} } @article {JavierLopez2004b, title = {PKI Design Based on the Use of On-line Certification Authorities}, journal = {International Journal of Information Security (IJIS)}, volume = {2}, number = {2}, year = {2004}, pages = {91-102}, publisher = {Springer}, abstract = {

Public-Key Infrastructures (PKIs) are considered the basis of the protocols and tools needed to guarantee the security demanded for new Internet applications like electronic commerce, government-citizen relationships and digital distribution. This paper introduces a new infrastructure design, Cert{\textquoteright}eM, a key management and certification system that is based on the structure of the electronic mail service and on the principle of near-certification. Cert{\textquoteright}eM provides secure means to identify users and distribute their public-key certificates, enhances the efficiency of revocation procedures, and avoids scalability and synchronization problems. Because we have considered the revocation problem as priority in the design process, and with a big influence in the rest of the PKI components, we have developed an alternative solution to the use of Certificate Revocation Lists (CRLs), which has become one of the strongest points in this new scheme.

}, issn = {1615-5262}, author = {Javier Lopez and Antonio Mana and Jose A. Montenegro and Juan J. Ortega} } @inproceedings {Zhou2004, title = {Protecting Free Roaming Agents against Result-Truncation Attack}, booktitle = {60th IEEE Vehicular Technology Conference (VTC{\textquoteright}04)}, year = {2004}, pages = {3271-3274}, publisher = {IEEE Vehicular Technology Society Press}, organization = {IEEE Vehicular Technology Society Press}, abstract = {

Mobile agents are especially useful in electronic commerce, for both wired and wireless environments. Nevertheless, there are still many security issues on mobile agents to be addressed, for example, data confidentiality, non-repudiability, forward privacy, publicly verifiable forward integrity, insertion defense, truncation defense, etc. One of the hardest security problems for free roaming agents is truncation defense where two visited hosts (or one revisited host) can collude to discard the partial results collected between their respective visits. We present a new scheme satisfying those security requirements, especially protecting free roaming agents against result-truncation attack.

}, keywords = {cryptographic protocol, mobile agent, Secure electronic commerce}, author = {Jianying Zhou and Jose A. Onieva and Javier Lopez} } @proceedings {1617, title = {Public Key Infrastructure, First European PKIWorkshop: Research and Applications, EuroPKI 2004, Samos Island, Greece, June 25-26, 2004, Proceedings}, journal = {EuroPKI}, volume = {3093}, year = {2004}, publisher = {Springer}, isbn = {3-540-22216-2}, editor = {Sokratis K. Katsikas and Stefanos Gritzalis and Javier Lopez} } @inproceedings {Onieva2003a, title = {Practical Service Charge for P2P Content Distribution}, booktitle = {Fifth International Conference on Information and Communications Security}, series = {LNCS}, volume = {2836}, year = {2003}, month = {October}, pages = {112 - 123}, publisher = {Springer}, organization = {Springer}, abstract = {

With emerging decentralized technologies, peer-to-peer (P2P) content distribution arises as a new model for storage and transmission of data. In this scenario, one peer can be playing different roles, either as a distributor or as a receiver of digital contents. In order to incentivize the legal distribution of these contents and prevent the network from free riders, we propose a charging model where distributors become merchants and receivers become customers. To help in the advertisement of digital contents and collection of payment details, an intermediary agent is introduced. An underlying P2P payment protocol presented in [1] is applied to this scenario without total trust on the intermediary agent.

}, author = {Jose A. Onieva and Jianying Zhou and Javier Lopez} } @inproceedings {JavierLopez2002i, title = {Perspectiva Composicional para el Dise{\~n}o y la Implementaci{\'o}n de una PKI}, booktitle = {I Congreso Internacional Sociedad de la Informaci{\'o}n}, year = {2002}, pages = {423-428}, address = {Las Palmas, Espa}, abstract = {
The important role of Public Key Infrastructures (PKIs) inside the general scope of Internet communication, and more precisely, inside electronic commerce, has driven us to the revision of actual procedures followed in the development of software of these elements that provide security and trust to the digital certification environment. In this work we introduce the actual results of a joint research project of the Security Group of the University of Malaga and the Department of Technology Innovation of Banesto regarding a PKI implementation. The originality of this work is that we have paid attention not only to functional aspects of the infrastructure, but also to the programming techniques used. Basically, we have developed a solution in which implementation has been guided by the increase in the study of software architectures and those paradigms that have emerged in parallel, as component orientation, software frameworks, and design patterns. The correct use of these techniques provide a different point of view that allows the development of every PKI building block in a modular and independent way.
}, author = {Javier Lopez and Jose A. Montenegro and Jose M. Troya} } @inproceedings {JavierLopez2002, title = {Protecci{\'o}n de Software basada en Tarjetas Inteligentes}, booktitle = {VII Reuni{\'o}n Espa{\~n}ola sobre Criptolog{\'\i}a y Seguridad de la Informaci{\'o}n (VII RECSI)}, year = {2002}, month = {Septiembre}, pages = {485-497}, address = {Oviedo, Espa}, author = {Javier Lopez and Antonio Mana and Juan J. Ortega and Ernesto Pimentel} } @inproceedings {JavierLopez2002b, title = {Protocol Engineering Applied to Formal Analysis of Security Systems}, booktitle = {International Conference on Infrastructure Security (InfraSec{\textquoteright}02)}, series = {LNCS}, volume = {2437}, year = {2002}, month = {October}, pages = {246-259}, publisher = {Springer-Verlag}, organization = {Springer-Verlag}, address = {Bristol, U.K.}, abstract = {

Every communication system requiring security properties is certainly critical. In order to study the security of communication systems, we have developed a methodology for the application of the formal analysis techniques of communication protocols to the analysis of cryptographic ones. We have extended the design and analysis phases with security properties. Our methodology uses a specification technique based on the HMSC/MSC requirement languages, and translates it into a generic schema for the SDL specification language, which is used for the analysis. Thus, the technique allows the specification of security protocols using a standard formal language and uses Object-Orientation for reusability purposes. The final goal is not only the formal specification of a security system, but to examine the possible attacks, and later use the specification in more complex systems.

}, author = {Javier Lopez and Juan J. Ortega and Jose M. Troya} } @article {1711, title = {Proyecto CASENET: Integraci{\'o}n del Dise{\~n}o y An{\'a}lisis de Protocolos Segurospara el Comerio-e}, journal = {Revista SIC: Seguridad en Inform{\'a}tica y Comunicaciones}, volume = {49}, year = {2002}, pages = {1-2}, issn = {1136-06}, author = {Javier Lopez} } @inproceedings {JavierLopez1999d, title = {Problem{\'a}tica de Seguridad para el Comercio Electr{\'o}nico en el Sector Tur{\'\i}stico}, booktitle = {I Congreso Nacional Turismo y Tecnolog{\'\i}a de la Informaci{\'o}n y las Comunicaciones (TURITEC{\textquoteright}99)}, year = {1999}, month = {Septiembre}, pages = {99-110}, abstract = {

Uno de los servicios que cada d\ía cobra m\ás importancia y que promete un cambio radical para las empresas es el comercio electr\ónico en Internet, pero tradicionalmente las empresas relacionadas con el turismo s\ólo han empleado la red para darse a conocer y ofertar sus productos. La raz\ón esencial es la desconfianza que existe sobre la seguridad de las transacciones llevadas a cabo en la red. La criptograf\ía de clave p\ública proporciona servicios adecuados para garantizar la seguridad de esas transacciones. Pero en la actualidad, algunos de esos servicios est\án menos desarrollados que otros; un ejemplo de ellos es el servicio de No-Repudio. En este art\ículo se estudian distintas formas de ofrecer servicios de no-repudio y se analizan sus ventajas y desventajas en funci\ón de las necesidades del entorno en que se utilicen.

}, author = {Javier Lopez and Javier Areitio and Felipe Rosello} } @inproceedings {JavierLopez1999a, title = {A Public Key Infrastructure for User Identification}, booktitle = {IFIP Working Conference on User Identification and Privacy Protection}, year = {1999}, month = {June}, pages = {209-227}, address = {Stockholm, Sweden}, abstract = {

While there is wide agreement on the immense potential of Internet, its growth and performance are adversely affected by security issues. Despite its impressive size, scope and reach, the Internet has not yet become a common vehicle for many of these new possibilities. Progress in fields as electronic commerce and government-citizen relationships have been limited by the open design of the network itself. Today, Public-Key Infrastructures are the basis of the protocols and tools needed to guarantee the security demanded in those fields. Trust management and user identification are also important issues that remain unresolved. This paper introduces a key management and user identification system, named Cert\’eM, that is based on the electronic mail service. Cert{\textquoteright}eM provides important advantages over existing Public-Key Infrastructures and user identification proposals.

}, author = {Javier Lopez and Antonio Mana and Juan J. Ortega} }