@article{FerIoT24,

title = {Trust interoperability in the Internet of Things},

author = {Carmen Fernandez-Gago and Davide Ferraris and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/FerIoT24.pdf},

doi = {https://doi.org/10.1016/j.iot.2024.101226},

year  = {2024},

date = {2024-12-31},

urldate = {2024-12-31},

journal = {Internet of Things},

volume = {26},

abstract = {The Internet of Things (IoT) is a paradigm where entities or things are interconnected, often in heterogeneous contexts. As the interconnection happens, things establish collaborations with others, sometimes under uncertainty. Although trust can help us overcome this uncertainty, things might not be able to process the information about trust coming from other things: each thing could have its own trust model, which means its own way to understand and measure trust. If new trust relationships are to be established, it would be desirable to have a mechanism of interoperability that allows the things to process the information about the other things in terms of trust. In this paper, we describe an interoperability framework for tackling the trust interoperability issues in IoT, depending on the different types of trust models that might co-exist in the same IoT scenario.},

keywords = {},

pubstate = {forthcoming},

tppubtype = {article}

}

@article{morales2024commag,

title = {Toward a Framework for Cost-Effective and Publicly Verifiable Confidential Computations in Blockchain},

author = {Daniel Morales and Isaac Agudo and Javier Lopez},

url = {/wp-content/papers/morales2024commag.pdf},

doi = {10.1109/MCOM.001.2300839},

issn = {1558-1896},

year  = {2024},

date = {2024-09-03},

urldate = {2024-09-03},

journal = {IEEE Communications Magazine},

abstract = {Blockchain technologies have introduced a compelling paradigm for a new understanding of security through decentralized networks and consensus mechanisms. However, they need all data to be public, which may be unacceptable for use cases such as biometric data processing or sensitive monetary transactions. Therefore, confidentiality is identified as a need in blockchain. Additionally, blockchain can contribute to confidential applications by providing publicly verifiable mechanisms, therefore enhancing security. This work presents a framework for cost-effective and publicly verifiable confidential computations in blockchain, by relying on secure multi-party computation committees and zero-knowledge proofs. Our framework supports arbitrary computations on confidential data enforced by smart contracts. Additionally, staking, incentives, and cheat identification are provided as solutions to enhance trust. We also provide a technical solution to embed secure multi-party computations within smart contracts by using the Promise programming pattern. Finally, a cost analysis is provided to justify the feasibility of the framework compared to other solutions.},

keywords = {},

pubstate = {forthcoming},

tppubtype = {article}

}

@article{SYRMAKESIS2024100678,

title = {DAR-LFC: A data-driven attack recovery mechanism for Load Frequency Control},

author = {Andrew D. Syrmakesis and Cristina Alcaraz and Nikos D. Hatziargyriou},

url = {https://www.sciencedirect.com/science/article/pii/S1874548224000192?dgcid=rss_sd_all},

doi = {https://doi.org/10.1016/j.ijcip.2024.100678},

issn = {1874-5482},

year  = {2024},

date = {2024-07-01},

urldate = {2024-01-01},

journal = {International Journal of Critical Infrastructure Protection},

volume = {45},

issue = {100678},

pages = {100678},

abstract = {In power systems, generation must be maintained in constant equilibrium with consumption. A key indicator for this balance is the frequency of the power grid. The load frequency control (LFC) system is responsible for maintaining the frequency close to its nominal value and the power deviation of tie-lines at their scheduled levels. However, the remote communication system of LFC exposes it to several cyber threats. A successful cyberattack against LFC attempts to affect the field measurements that are transferred though its remote control loop. In this work, a data-driven, attack recovery method is proposed against denial of service and false data injection attacks, called DAR-LFC. For this purpose, a deep neural network is developed that generates estimations of the area control error (ACE) signal. When a cyberattack against the LFC occurs, the proposed estimator can temporarily compute and replace the affected ACE, mitigating the effects of the cyberattacks. The effectiveness and the scalability of the DAR-LFC is verified on a single and a two area LFC simulations in MATLAB/Simulink.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2023a,

title = {Protecting Digital Twin Networks for 6G-enabled Industry 5.0 Ecosystems},

author = {Cristina Alcaraz and Javier Lopez},

url = {/wp-content/papers/Alcaraz2023a.pdf

https://ieeexplore.ieee.org/abstract/document/10239369},

doi = {10.1109/MNET.004.2200529},

issn = {0890-8044},

year  = {2023},

date = {2023-12-31},

urldate = {2023-12-31},

journal = {IEEE Network Magazine},

volume = {37},

number = {2},

pages = {302-308},

publisher = {IEEE},

abstract = {New industrial paradigms, such as the Industrial Internet of Things (IIoT) and Industry 5.0, are emerging in industrial contexts with the aim of fostering quality in operational processes. With the expected launch of 6G in the coming years, IIoT networks in Industry 5.0 ecosystems can leverage 6G technology and its support for training machine learning models using Digital Twins (DTs), embedded in DT Networks (DTNs), to transparently and continuously optimize their communications. Unfortunately, the use of these technologies, in turn, intensifies the attack surface and poses a serious threat to the new goals of Industry 5.0, such as improving the user experience, sustainability and resilience. This article therefore proposes a layered protection framework for 6G-enabled IIoT environments, where not only DTs and DTNs are fully protected, but also the whole 6G ecosystem, complying with the expected goals of Industry 5.0. To achieve this, the framework identifies for each protection layer a set of security and privacy services to subsequently relate them to existing computing infrastructures (cloud, edge, edge-cloud) and provide the best approach for future IIoT deployments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{surveyIoTrust2023,

title = {A Survey on IoT Trust Model Frameworks},

author = {Davide Ferraris and Carmen Fernandez-Gago and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/surveyIoTrust2023.pdf},

doi = {10.1007/s11227-023-05765-4},

year  = {2023},

date = {2023-11-17},

urldate = {2023-11-17},

journal = {The Journal of Supercomputing},

abstract = {Trust can be considered as a multidisciplinary concept, which is strongly related to the context and it falls in different fields such as Philosophy, Psychology or Computer Science. Trust is fundamental in every relationship, because without it, an entity will not interact with other entities. This aspect is very important especially in the Internet of Things (IoT), where many entities produced by different vendors and created for different purposes have to interact among them through the internet often under uncertainty. Trust can overcome this uncertainty, creating a strong basis to ease the process of interaction among these entities. We believe that considering trust in the IoT is fundamental, and in order to implement it in any IoT entity, it is fundamental to consider it through the whole System Development Life Cycle. In this paper, we propose an analysis of different works that consider trust for the IoT. We will focus especially on the analysis of frameworks that have been developed in order to include trust in the IoT. We will make a classification of them providing a set of parameters that we believe are fundamental in order to properly consider trust in the IoT. Thus, we will identify important aspects to be taken into consideration when developing frameworks that implement trust in the IoT, finding gaps and proposing possible solutions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{jaime2023,

title = {Strenghtening Privacy and Data Security in Biomedical Microelectromechanical Systems by IoT Communication Security and Protection in Smart Healthcare},

author = {Francisco Jaime, Antonio Mu\~{n}oz, Francisco Rodr\'{i}guez-G\'{o}mez, Antonio Jerez-Calero},

editor = {MDPI},

doi = {10.3390/s23218944},

issn = {14248220},

year  = {2023},

date = {2023-11-03},

urldate = {2023-11-03},

journal = {Sensors},

volume = {23},

issue = {21},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2023b,

title = {OCPP in the spotlight: threats and countermeasures for electric vehicle charging infrastructures 4.0},

author = {Cristina Alcaraz and Jesus Cumplido and Alicia Trivi\~{n}o},

url = {/wp-content/papers/Alcaraz2023b.pdf

https://link.springer.com/article/10.1007/s10207-023-00698-8},

doi = {10.1007/s10207-023-00698-8},

issn = {1615-5262},

year  = {2023},

date = {2023-05-05},

urldate = {2023-05-05},

journal = {International Journal of Information Security},

publisher = {Springer},

address = {Springer Verlag},

abstract = {Undoubtedly, Industry 4.0 in the energy sector improves the conditions for automation, generation and distribution of energy, increasing the rate of electric vehicle manufacturing in recent years. As a result, more grid-connected charging infrastructures are being installed, whose charging stations (CSs) can follow standardized architectures, such as the one proposed by the open charge point protocol (OCPP). The most recent version of this protocol is v.2.0.1, which includes new security measures at device and communication level to cover those security issues identified in previous versions. Therefore, this paper analyzes OCPP-v2.0.1 to determine whether the new functions may still be susceptible to specific cyber and physical threats, and especially when CSs may be connected to microgrids. To formalize the study, we first adapted the well-known threat analysis methodology, STRIDE, to identify and classify threats in terms of control and energy, and subsequently we combine it with DREAD for risk assessment. The analyses indicate that, although OCPP-v2.0.1 has evolved, potential security risks still remain, requiring greater protection in the future.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{morales2023psi,

title = {Private set intersection: A systematic literature review},

author = {Daniel Morales and Isaac Agudo and Javier Lopez},

url = {/wp-content/papers/morales2023psi.pdf

https://www.sciencedirect.com/science/article/pii/S1574013723000345},

doi = {10.1016/j.cosrev.2023.100567},

issn = {1574-0137},

year  = {2023},

date = {2023-05-01},

urldate = {2023-05-01},

journal = {Computer Science Review},

volume = {49},

number = {100567},

publisher = {Elsevier},

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 = {},

pubstate = {published},

tppubtype = {article}

}

@article{Roman2023a,

title = {Current Perspectives on Securing Critical Infrastructures’ Supply Chains},

author = {Rodrigo Roman and Cristina Alcaraz and Javier Lopez and Kouichi Sakurai},

url = {/wp-content/papers/Roman2023a.pdf},

doi = {10.1109/MSEC.2023.3247946},

issn = {1540-7993},

year  = {2023},

date = {2023-03-08},

urldate = {2023-03-08},

journal = {IEEE Security \& Privacy},

volume = {21},

number = {4},

pages = {29-38},

publisher = {IEEE},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{MUNOZ2023103180,

title = {A survey on the (in)security of Trusted Execution Environments},

author = {Antonio Mu\~{n}oz and Ruben Rios and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/MUNOZ2023103180.pdf

https://www.sciencedirect.com/science/article/pii/S0167404823000901},

doi = {10.1016/j.cose.2023.103180},

issn = {0167-4048},

year  = {2023},

date = {2023-01-01},

urldate = {2023-01-01},

journal = {Computers \& Security},

pages = {103-180},

publisher = {Elsevier},

address = {In Press},

abstract = {As the number of security and privacy attacks continue to grow around the world, there is an ever increasing need to protect our personal devices. As a matter of fact, more and more manufactures are relying on Trusted Execution Environments (TEEs) to shield their devices. In particular, ARM TrustZone (TZ) is being widely used in numerous embedded devices, especially smartphones, and this technology is the basis for secure solutions both in industry and academia. However, as shown in this paper, TEE is not bullet-proof and it has been successfully attacked numerous times and in very different ways. To raise awareness among potential stakeholders interested in this technology, this paper provides an extensive analysis and categorization of existing vulnerabilities in TEEs and highlights the design flaws that led to them. The presented vulnerabilities, which are not only extracted from existing literature but also from publicly available exploits and databases, are accompanied by some effective countermeasures to reduce the likelihood of new attacks. The paper ends with some appealing challenges and open issues.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{munoz2022,

title = {A Test Environment for Wireless Hacking in Domestic IoT Scenarios},

author = {Antonio Mu\~{n}oz and Carmen Fernandez-Gago and Roberto Lopez-Villa},

url = {/wp-content/papers/munoz2022.pdf},

doi = {10.1007/s11036-022-02046-x},

issn = {1383-469X},

year  = {2022},

date = {2022-10-01},

urldate = {2022-10-01},

journal = {Mobile Networks and Applications},

publisher = {Springer},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{suciu2022samgrid,

title = {SAMGRID: Security Authorization and Monitoring Module Based on SealedGRID Platform},

author = {George Suciu and Aristeidis Farao and Giorgio Bernardinetti and Ivan Palam\'{a} and Mari-Anais Sachian and Alexandru Vulpe and Marius-Constantin Vochin and Pavel Muresan and Michail Bampatsikos and Antonio Mu\~{n}oz and Christos Xenakis},

url = {/wp-content/papers/suciu2022samgrid.pdf

https://www.mdpi.com/1424-8220/22/17/6527},

doi = {10.3390/s22176527},

issn = {1424-8220},

year  = {2022},

date = {2022-08-30},

urldate = {2022-08-30},

journal = {SENSORS},

volume = {22},

number = {17},

issue = {6527},

abstract = {IoT devices present an ever-growing domain with multiple applicability. This technology has favored and still favors many areas by creating critical infrastructures that are as profitable as possible. This paper presents a hierarchical architecture composed of different licensing entities that manage access to different resources within a network infrastructure. They are conducted on the basis of well-drawn policy rules. At the same time, the security side of these resources is also placed through a context awareness module. Together with this technology, IoT is used and Blockchain is enabled (for network consolidation, as well as the transparency with which to monitor the platform). The ultimate goal is to implement a secure and scalable security platform for the Smart Grid. The paper presents the work undertaken in the SealedGRID project and the steps taken for implementing security policies specifically tailored to the Smart Grid, based on advanced concepts such as Opinion Dynamics and Smart Grid-related Attribute-based Access Control.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Syrmakesis2022,

title = {Classifying resilience approaches for protecting smart grids against cyber threats},

author = {Andrew D. Syrmakesis and Cristina Alcaraz and Nikos D. Hatziargyriou},

url = {/wp-content/papers/Syrmakesis2022.pdf

https://link.springer.com/content/pdf/10.1007/s10207-022-00594-7.pdf},

doi = {https://doi.org/10.1007/s10207-022-00594-7},

issn = {1615-5262},

year  = {2022},

date = {2022-05-01},

urldate = {2022-05-01},

journal = {International Journal of Information Security},

volume = {21},

pages = {1189\textendash1210},

publisher = {Springer},

address = {Springer Verlag},

abstract = {Smart grids (SG) draw the attention of cyber attackers due to their vulnerabilities, which are caused by the usage of heterogeneous communication technologies and their distributed nature. While preventing or detecting cyber attacks is a well-studied field of research, making SG more resilient against such threats is a challenging task. This paper provides a classification of the proposed cyber resilience methods against cyber attacks for SG. This classification includes a set of studies that propose cyber-resilient approaches to protect SG and related cyber-physical systems against unforeseen anomalies or deliberate attacks. Each study is briefly analyzed and is associated with the proper cyber resilience technique which is given by the National Institute of Standards and Technology in the Special Publication 800-160. These techniques are also linked to the different states of the typical resilience curve. Consequently, this paper highlights the most critical challenges for achieving cyber resilience, reveals significant cyber resilience aspects that have not been sufficiently considered yet and, finally, proposes scientific areas that should be further researched in order to enhance the cyber resilience of SG.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{rios2022cpa,

title = {Constrained Proximity Attacks on Mobile Targets},

author = {Xueou Wang and Xiaolu Hou and Ruben Rios and Nils Ole Tippenhauer and Martin Ochoa},

url = {/wp-content/papers/rios2022cpa.pdf},

doi = {10.1145/3498543},

issn = {2471-2566},

year  = {2022},

date = {2022-05-01},

urldate = {2022-05-01},

journal = {ACM Transactions on Privacy and Security (TOPS)},

volume = {25},

number = {10},

pages = {1 - 29},

publisher = {Association for Computer Machinery (ACM)},

abstract = {Proximity attacks allow an adversary to uncover the location of a victim by repeatedly issuing queries with fake location data. These attacks have been mostly studied in scenarios where victims remain static and there are no constraints that limit the actions of the attacker. In such a setting, it is not difficult for the attacker to locate a particular victim and quantifying the effort for doing so is straightforward. However, it is far more realistic to consider scenarios where potential victims present a particular mobility pattern. In this paper, we consider abstract (constrained and unconstrained) attacks on services that provide location information on other users in the proximity. We derive strategies for constrained and unconstrained attackers, and show that when unconstrained they can practically achieve success with theoretically optimal effort. We then propose a simple yet effective constraint that may be employed by a proximity service (for example, running in the cloud or using a suitable two-party protocol) as countermeasure to increase the effort for the attacker several orders of magnitude both in simulated and real-world cases.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2022b,

title = {Digital Twin: A Comprehensive Survey of Security Threats},

author = {Cristina Alcaraz and Javier Lopez},

url = {/wp-content/papers/Alcaraz2022b.pdf

https://ieeexplore.ieee.org/document/9765576},

doi = {10.1109/COMST.2022.3171465},

issn = {1553-877X},

year  = {2022},

date = {2022-04-01},

urldate = {2022-04-01},

journal = {IEEE Communications Surveys \& Tutorials},

volume = {24},

number = {thirdquarter 2022},

pages = {1475 - 1503},

publisher = {IEEE},

address = {IEEE},

abstract = {Industry 4.0 is having an increasingly positive impact on the value chain by modernizing and optimizing the production and distribution processes. In this streamline, the digital twin (DT) is one of the most cutting-edge technologies of Industry 4.0, providing simulation capabilities to forecast, optimize and estimate states and configurations. In turn, these technological capabilities are encouraging industrial stakeholders to invest in the new paradigm, though an increased focus on the risks involved is really needed. More precisely, the deployment of a DT is based on the composition of technologies such as cyber-physical systems, the Industrial Internet of Things, edge computing, virtualization infrastructures, artificial intelligence and big data. However, the confluence of all these technologies and the implicit interaction with the physical counterpart of the DT in the real world generate multiple security threats that have not yet been sufficiently studied. In that context, this paper analyzes the current state of the DT paradigm and classifies the potential threats associated with it, taking into consideration its functionality layers and the operational requirements in order to achieve a more complete and useful classification. We also provide a preliminary set of security recommendations and approaches that can help to ensure the appropriate and trustworthy use of a DT.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ishak22,

title = {Learning multi-party adversarial encryption and its application to secret sharing},

author = {Ishak Meraouche and Sabyasachi Dutta and Sraban Kumar Mohanty and Isaac Agudo and Kouichi Sakurai},

url = {/wp-content/papers/ishak22.pdf},

doi = {10.1109/ACCESS.2022.3223430},

issn = {2169-3536},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {IEEE Access},

publisher = {IEEE},

abstract = {Neural networks based cryptography has seen a significant growth since the introduction of adversarial cryptography which makes use of Generative Adversarial Networks (GANs) to build neural networks that can learn encryption. The encryption has been proven weak at first but many follow up works have shown that the neural networks can be made to learn the One Time Pad (OTP) and produce perfectly secure ciphertexts. To the best of our knowledge, existing works only considered communications between two or three parties. In this paper, we show how multiple neural networks in an adversarial setup can remotely synchronize and establish a perfectly secure communication in the presence of different attackers eavesdropping their communication. As an application, we show how to build Secret Sharing Scheme based on this perfectly secure multi-party communication. The results show that it takes around 45,000 training steps for 4 neural networks to synchronize and reach equilibria. When reaching equilibria, all the neural networks are able to communicate between each other and the attackers are not able to break the ciphertexts exchanged between them.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{rios2022pmec,

title = {Personal IoT Privacy Control at the Edge},

author = {Ruben Rios and Jose A. Onieva and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/rios2022pmec.pdf},

doi = {10.1109/MSEC.2021.3101865},

issn = {1540-7993},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {IEEE Security \& Privacy},

volume = {20},

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.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Flamini2022,

title = {Towards Trustworthy Autonomous Systems: Taxonomies and Future Perspectives},

author = {Francesco Flammini and Cristina Alcaraz and Emanuele Bellini and Stefano Marrone and Javier Lopez and Andrea Bondavalli},

url = {/wp-content/papers/Flamini2022.pdf

https://ieeexplore.ieee.org/abstract/document/9979717/authors$#$authors},

doi = {10.1109/TETC.2022.3227113},

issn = {2168-6750},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {IEEE Transactions on Emerging Topics in Computing},

publisher = {IEEE},

abstract = {The class of Trustworthy Autonomous Systems (TAS) includes cyber-physical systems leveraging on self-x technologies that make them capable to learn, adapt to changes, and reason under uncertainties in possibly critical applications and evolving environments. In the last decade, there has been a growing interest in enabling artificial intelligence technologies, such as advanced machine learning, new threats, such as adversarial attacks, and certification challenges, due to the lack of sufficient explainability. However, in order to be trustworthy, those systems also need to be dependable, secure, and resilient according to well-established taxonomies, methodologies, and tools. Therefore, several aspects need to be addressed for TAS, ranging from proper taxonomic classification to the identification of research opportunities and challenges. Given such a context, in this paper address relevant taxonomies and research perspectives in the field of TAS. We start from basic definitions and move towards future perspectives, regulations, and emerging technologies supporting development and operation of TAS.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2021a,

title = {Stakeholder Perspectives and Requirements on Cybersecurity in Europe},

author = {Simone Fischer-H\"{u}bner and Cristina Alcaraz and Afonso Ferreira and Carmen Fernandez-Gago and Javier Lopez and Evangelos Markatos and Lejla Islami and Mahdi Akil},

url = {/wp-content/papers/Alcaraz2021a.pdf

https://www.sciencedirect.com/science/article/pii/S2214212621001381},

doi = {10.1016/j.jisa.2021.102916},

issn = {2214-2126},

year  = {2021},

date = {2021-09-01},

urldate = {2021-09-01},

journal = {Journal of Information Security and Applications},

volume = {61},

number = {102916},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{anto2021,

title = {P2ISE: Preserving Project Integrity in CI/CD Based on Secure Elements},

author = {Antonio Mu\~{n}oz and Aristeidis Farao and Ryan Casas and Christos Xenakis},

url = {/wp-content/papers/anto2021.pdf},

issn = {2078-2489,},

year  = {2021},

date = {2021-08-01},

urldate = {2021-08-01},

journal = {Information},

volume = {12},

number = {357},

publisher = {MDPI},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Agudo2020,

title = {A Blockchain Approach for Decentralized V2X (D-V2X)},

author = {Isaac Agudo and Manuel Montenegro-G\'{o}mez and Javier Lopez},

url = {/wp-content/papers/Agudo2020.pdf},

doi = {10.1109/TVT.2020.3046640},

issn = {0018-9545},

year  = {2021},

date = {2021-05-01},

urldate = {2021-05-01},

journal = {IEEE Transactions on Vehicular Technology},

volume = {70},

number = {5},

pages = {4001 - 4010},

publisher = {IEEE},

abstract = {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.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{lopez2020,

title = {Digital Twins for Intelligent Authorization in the B5G-enabled Smart Grid},

author = {Javier Lopez and Juan E. Rubio and Cristina Alcaraz},

url = {/wp-content/papers/lopez2020.pdf

https://ieeexplore.ieee.org/document/9430900},

doi = {10.1109/MWC.001.2000336},

issn = {1536-1284},

year  = {2021},

date = {2021-04-01},

urldate = {2021-04-01},

journal = {IEEE Wireless Communications},

volume = {28},

pages = {48-55},

publisher = {IEEE},

abstract = {Beyond fifth generation (B5G) communication networks and computation paradigms in the edge are expected to be integrated into power grid infrastructures over the coming years. In this sense, AI technologies will play a fundamental role to efficiently manage dynamic information flows of future applications, which impacts the authorization policies applied in such a complex scenario. This article studies how digital twins can evolve their context awareness capabilities and simulation technologies to anticipate faults or to detect cyber-security issues in real time, and update access control policies accordingly. Our study analyzes the evolution of monitoring platforms and architecture decentralization, including the application of machine learning and blockchain technologies in the smart grid, toward the goal of implementing autonomous and self-learning agents in the medium and long term. We conclude this study with future challenges on applying digital twins to B5G-based smart grid deployments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ferraris2020b,

title = {A model-driven approach to ensure trust in the IoT},

author = {Davide Ferraris and Carmen Fernandez-Gago and Javier Lopez},

url = {/wp-content/papers/ferraris2020b.pdf},

doi = {10.1186/s13673-020-00257-3},

issn = {2192-1962},

year  = {2020},

date = {2020-12-01},

urldate = {2020-12-01},

journal = {Human-centric Computing and Information Sciences},

volume = {10},

number = {50},

publisher = {Springer},

abstract = {The Internet of Things (IoT) is a paradigm that permits smart entities to be interconnected anywhere and anyhow. IoT opens new opportunities but also rises new issues. 

In this dynamic environment, trust is useful to mitigate these issues. In fact, it is important that the smart entities could know and trust the other smart entities in order to collaborate with them. 

So far, there is a lack of research when considering trust through the whole System Development Life Cycle (SDLC) of a smart IoT entity. 

In this paper, we suggest a new approach that considers trust not only at the end of the SDLC but also at the start of it. More precisely, we explore the modeling phase proposing a model-driven approach extending UML and SysML considering trust and its related domains, such as security and privacy. 

We propose stereotypes for each diagram in order to give developers a way to represent trust elements in an effective way. 

Moreover, we propose two new diagrams that are very important for the IoT: a traceability diagram and a context diagram. 

This model-driven approach will help developers to model the smart IoT entities according to the requirements elicited in the previous phases of the SDLC. 

These models will be a fundamental input for the following and final phases of the SDLC.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Rubio2020IIoT,

title = {Integration of a Threat Traceability Solution in the Industrial Internet of Things},

author = {Juan E. Rubio and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/Rubio2020IIoT.pdf},

doi = {10.1109/TII.2020.2976747},

issn = {1551-3203},

year  = {2020},

date = {2020-10-01},

urldate = {2020-10-01},

journal = {IEEE Transactions on Industrial Informatics},

volume = {16},

number = {6575-6583},

publisher = {IEEE},

abstract = {In Industrial Internet of Things (IIoT) scenarios, where a plethora of IoT technologies coexist with consolidated industrial infrastructures, the integration of security mechanisms that provide protection against cyber-security attacks becomes a critical challenge. Due to the stealthy and persistent nature of some of these attacks, such as Advanced Persistent Threats, it is crucial to go beyond traditional Intrusion Detection Systems for the traceability of these attacks. In this sense, Opinion Dynamics poses a novel approach for the correlation of anomalies, which has been successfully applied to other network security domains. In this paper, we aim to analyze its applicability in the IIoT from a technical point of view, by studying its deployment over different IIoT architectures and defining a common framework for the acquisition of data considering the computational constraints involved. The result is a beneficial insight that demonstrates the feasibility of this approach when applied to upcoming IIoT infrastructures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{JUDAS2020,

title = {Becoming JUDAS: Correlating Users and Devices during a Digital Investigation},

author = {Ana Nieto},

url = {/wp-content/papers/JUDAS2020.pdf

https://ieeexplore.ieee.org/document/9069950},

doi = {10.1109/TIFS.2020.2988602},

issn = {1556-6013},

year  = {2020},

date = {2020-07-01},

urldate = {2020-07-01},

journal = {IEEE Transactions on Information Forensics \& Security},

volume = {15},

pages = {3325-3334},

publisher = {IEEE},

abstract = {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 emphopen source intelligence (OSINT) sources when needed. In order to illustrate this approach, the proposed methodology is implemented in the emphJSON 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.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2020a,

title = {Blockchain-Assisted Access for Federated Smart Grid Domains: Coupling and Features},

author = {Cristina Alcaraz and Juan E. Rubio and Javier Lopez},

url = {/wp-content/papers/Alcaraz2020a.pdf},

issn = {0743-7315},

year  = {2020},

date = {2020-06-01},

urldate = {2020-06-01},

journal = {Journal of Parallel and Distributed Computing},

volume = {144},

pages = {124-135},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ferraris2020,

title = {A Trust Model for Popular Smart Home Devices},

author = {Davide Ferraris and Daniel Bastos and Carmen Fernandez-Gago and Fadi El-Moussa},

url = {/wp-content/papers/ferraris2020.pdf

https://link.springer.com/article/10.1007/s10207-020-00519-2},

doi = {10.1007/s10207-020-00519-2},

issn = {1615-5262},

year  = {2020},

date = {2020-01-01},

urldate = {2020-01-01},

journal = {International Journal of Information Security},

publisher = {Springer},

abstract = {Nowadays, smart home devices like Amazon Echo and Google Home have reached mainstream popularity. 

Being in the homes of users, these devices are intrinsically intrusive, being able to access details such as users’ name, gender, home address, calendar appointments and others. 

There are growing concerns about indiscriminate data collection and invasion of user privacy in smart home devices, but studies show that perceived benefits are exceeding perceived risks when it comes to consumers. 

As a result, consumers are placing a lot of trust in these devices, sometimes without realizing it. 

Improper trust assumptions and security controls can lead to unauthorized access and control of the devices, which can result in serious consequences. 

In this paper, we explore the behaviour of devices such as Amazon Echo and Google Home in a smart home setting with respect to trust relationships and propose a trust model to improve these relationships among all the involved actors. 

We have evaluated how trust was built and managed from the initial set up phase to the normal operation phase, during which we performed a number of interaction tests with different types of users (i.e. owner, guests). 

As a result, we were able to assess the effectiveness of the provided security controls and identify potential relevant security issues. In order to address the identified issues, we defined a trust model and propose a solution based on it for further securing smart home systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{alcaraz2019a,

title = {Covert Channels-based Stealth Attacks in Industry 4.0},

author = {Cristina Alcaraz and Giuseppe Bernieri and Federica Pascucci and Javier Lopez and Roberto Setola},

url = {/wp-content/papers/alcaraz2019a.pdf

https://ieeexplore.ieee.org/document/8715420?source=authoralert},

doi = {10.1109/JSYST.2019.2912308},

issn = {1932-8184},

year  = {2019},

date = {2019-12-01},

urldate = {2019-12-01},

journal = {IEEE Systems Journal.},

volume = {13},

pages = {3980-3988},

publisher = {IEEE},

abstract = {Industry 4.0 advent opens several cyber-threats scenarios originally designed for classic information technology, drawing the attention to the serious risks for the modern industrial control networks. To cope with this problem, in this paper we address the security issues related to covert channels applied to industrial networks, identifying the new vulnerability points when information technologies converge with operational technologies such as edge computing infrastructures. Specifically, we define two signaling strategies where we exploit the Modbus/TCP protocol as target to set up a covert channel. Once the threat channel is established, passive and active offensive attacks (i.e. data exfiltration and command an control, respectively) are further exploited by implementing and testing them on a real Industrial Internet of Things testbed. The experimental results highlight the potential damage of such specific threats, and the easy extrapolation of the attacks to other types of channels in order to show the new risks for Industry 4.0. Related to this, we discuss some countermeasures to offer an overview of possible mitigation and defense measures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{rub2019cose,

title = {Current Cyber-Defense Trends in Industrial Control Systems},

author = {Juan E. Rubio and Cristina Alcaraz and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/rub2019cose.pdf},

doi = {10.1016/j.cose.2019.06.015},

issn = {0167-4048},

year  = {2019},

date = {2019-11-01},

urldate = {2019-11-01},

journal = {Computers \& Security Journal},

volume = {87},

publisher = {Elsevier},

abstract = {Advanced Persistent Threats (APTs) have become a serious hazard for any critical infrastructure, as a single solution to protect all industrial assets from these complex attacks does not exist. It is then essential to understand what are the defense mechanisms that can be used as a first line of defense. For this purpose, this article will firstly study the spectrum of attack vectors that APTs can use against existing and novel elements of an industrial ecosystem. Afterwards, this article will provide an analysis of the evolution and applicability of Intrusion Detection Systems (IDS) that have been proposed in both the industry and academia.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{onieva2019vec,

title = {Edge-Assisted Vehicular Networks Security},

author = {Jose A. Onieva and Ruben Rios and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/onieva2019vec.pdf},

doi = {10.1109/JIOT.2019.2904323},

issn = {2327-4662},

year  = {2019},

date = {2019-10-01},

urldate = {2019-10-01},

journal = {IEEE Internet of Things Journal},

volume = {6},

pages = {8038-8045},

publisher = {IEEE Computer Society},

abstract = {Edge Computing paradigms are expected to solve some major problems affecting current application scenarios that rely on Cloud computing resources to operate. These novel paradigms will bring computational resources closer to the users and by doing so they will not only reduce network latency and bandwidth utilization but will also introduce some attractive context-awareness features to these systems. In this paper we show how the enticing features introduced by Edge Computing paradigms can be exploited to improve security and privacy in the critical scenario of vehicular networks (VN), especially existing authentication and revocation issues. In particular, we analyze the security challenges in VN and describe three deployment models for vehicular edge computing, which refrain from using vehicular- to-vehicular communications. The result is that the burden imposed to vehicles is considerably reduced without sacrificing the security or functional features expected in vehicular scenarios.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nunez19,

title = {Escrowed decryption protocols for lawful interception of encrypted data},

author = {David Nu\~{n}ez and Isaac Agudo and Javier Lopez},

url = {/wp-content/papers/nunez19.pdf},

doi = {10.1049/iet-ifs.2018.5082},

issn = {1751-8709},

year  = {2019},

date = {2019-09-01},

urldate = {2019-09-01},

journal = {IET Information Security},

volume = {13},

pages = {498 \textendash 507},

publisher = {IET},

abstract = {Escrowed decryption schemes (EDSs) are public-key encryption schemes with an escrowed decryption functionality that allows authorities to decrypt encrypted messages under investigation, following a protocol that involves a set of trusted entities called ‘custodians’; only if custodians collaborate, the requesting authority is capable of decrypting encrypted data. This type of cryptosystem represents an interesting trade-off to privacy versus surveillance dichotomy. In this study, the authors propose two EDSs where they use proxy re-encryption to build the escrowed decryption capability, so that custodians re-encrypt ciphertexts, in a distributed way, upon request from an escrow authority, and the re-encrypted ciphertexts can be opened only by the escrow authority. Their first scheme, called EDS, follows an all-or-nothing approach, which means that escrow decryption only works when all custodians collaborate. Their second scheme, called threshold EDS, supports a threshold number of custodians for the escrow decryption operation. They propose definitions of semantic security with respect to the authorities, custodians and external entities, and prove the security of their schemes, under standard pairing-based hardness assumptions. Finally, they present a theoretical and experimental analysis of the performance of both schemes, which show that they are applicable to real-world scenarios.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RubioSIJCS19,

title = {Tracking APTs in Industrial Ecosystems: A Proof of Concept},

author = {Juan E. Rubio and Rodrigo Roman and Cristina Alcaraz and Yan Zhang},

url = {/wp-content/papers/RubioSIJCS19.pdf},

issn = {0167-4048},

year  = {2019},

date = {2019-09-01},

urldate = {2019-09-01},

journal = {Journal of Computer Security},

volume = {27},

pages = {521-546},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{roman2018VIS,

title = {Immune System for the Internet of Things using Edge Technologies},

author = {Rodrigo Roman and Ruben Rios and Jose A. Onieva and Javier Lopez},

url = {/wp-content/papers/roman2018VIS.pdf

https://ieeexplore.ieee.org/document/8449989/},

doi = {10.1109/JIOT.2018.2867613},

issn = {2327-4662},

year  = {2019},

date = {2019-06-01},

urldate = {2019-06-01},

journal = {IEEE Internet of Things Journal},

volume = {6},

pages = {4774-4781},

publisher = {IEEE Computer Society},

abstract = {The Internet of Things (IoT) and Edge Computing are starting to go hand in hand. By providing cloud services close to end-users, edge paradigms enhance the functionality of IoT deployments, and facilitate the creation of novel services such as augmented systems. Furthermore, the very nature of these paradigms also enables the creation of a proactive defense architecture, an immune system, which allows authorized immune cells (e.g., virtual machines) to traverse edge nodes and analyze the security and consistency of the underlying IoT infrastructure. In this article, we analyze the requirements for the development of an immune system for the IoT, and propose a security architecture that satisfies these requirements. We also describe how such a system can be instantiated in Edge Computing infrastructures using existing technologies. Finally, we explore the potential application of immune systems to other scenarios and purposes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{kolar2019trust,

title = {A Model Specification for the Design of Trust Negotiations},

author = {Martin Kolar and Carmen Fernandez-Gago and Javier Lopez},

url = {/wp-content/papers/kolar2019trust.pdf

https://www.sciencedirect.com/science/article/pii/S0167404818310484},

doi = {10.1016/j.cose.2019.03.024},

issn = {0167-4048},

year  = {2019},

date = {2019-04-01},

urldate = {2019-04-01},

journal = {Computers \& Security},

volume = {84},

pages = {288-300},

publisher = {Elsevier},

abstract = {Trust negotiation is a type of trust management model for establishing trust between entities by a mutual exchange of credentials. This approach was designed for online environments, where the attributes of users, such as skills, habits, behaviour and experience are unknown. Required criteria of trust negotiation must be supported by a trust negotiation model in order to provide a functional, adequately robust and efficient application. Such criteria were identified previously. In this paper we are presenting a model specification using a UML-based notation for the design of trust negotiation. This specification will become a part of the Software Development Life Cycle, which will provide developers a strong tool for incorporating trust and trust-related issues into the software they create. The specification defines components and their layout for the provision of the essential functionality of trust negotiation on one side as well as optional, additional features on the other side. The extra features make trust negotiation more robust, applicable for more scenarios and may provide a privacy protection functionality.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{sarita2018,

title = {Detection of Node Capture Attack in Wireless Sensor Networks},

author = {Sarita Agrawal and Manik Lal Das and Javier Lopez},

issn = {1932-8184},

year  = {2019},

date = {2019-03-01},

urldate = {2019-03-01},

journal = {IEEE Systems Journal},

volume = {13},

pages = {238 - 247},

publisher = {IEEE},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HFNR2019,

title = {Cybersecurity Profiles based on Human-Centric IoT Devices},

author = {Ana Nieto and Ruben Rios},

url = {/wp-content/papers/HFNR2019.pdf},

doi = {10.1186/s13673-019-0200-y},

issn = {2192-1962},

year  = {2019},

date = {2019-01-01},

urldate = {2019-01-01},

journal = {Human-centric Computing and Information Sciences},

volume = {9},

number = {1},

pages = {1-23},

publisher = {Springer},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ferraris2019,

title = {TrUStAPIS: A Trust Requirements Elicitation Method for IoT},

author = {Davide Ferraris and Carmen Fernandez-Gago},

url = {/wp-content/papers/ferraris2019.pdf

https://link.springer.com/article/10.1007%2Fs10207-019-00438-x},

doi = {10.1007/s10207-019-00438-x},

issn = {1615-5262},

year  = {2019},

date = {2019-01-01},

urldate = {2019-01-01},

journal = {International Journal of Information Security},

pages = {111-127},

publisher = {Springer},

abstract = {The Internet of Things (IoT) is an environment of interconnected entities, which are identifiable, usable and controllable via the Internet. Trust is useful for a system such as the IoT as the entities involved would like to know how the other entities they have to interact with are going to perform. 

When developing an IoT entity, it will be desirable to guarantee trust during its whole life cycle. Trust domain is strongly dependent on other domains such as security and privacy. 

To consider these domains as a whole and to elicit the right requirements since the first phases of the System Development Life Cycle (SDLC) is a key point when developing an IoT entity. 

This paper presents a requirements elicitation method focusing on trust plus other domains such as security, privacy and usability that increase the trust level of the IoT entity developed. To help the developers to elicit the requirements, we propose a JavaScript Notation Object (JSON) template containing all the key elements that must be taken into consideration. 

We emphasize on the importance of the concept of traceability. This property permits to connect all the elicited requirements guaranteeing more control on the whole requirements engineering process.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{alcarazlopez-IEEESystems-2017,

title = {A Cyber-Physical Systems-Based Checkpoint Model for Structural Controllability},

author = {Cristina Alcaraz and Javier Lopez},

url = {/wp-content/papers/alcarazlopez-IEEESystems-2017.pdf

http://ieeexplore.ieee.org/document/8057984/},

doi = {10.1109/JSYST.2017.2740719},

issn = {1932-8184},

year  = {2018},

date = {2018-12-01},

urldate = {2018-12-01},

journal = {IEEE Systems Journal},

volume = {12},

pages = {3543-3554},

publisher = {IEEE},

abstract = {The protection of critical user-centric applications, such as Smart Grids and their monitoring systems, has become one of the most cutting-edge research areas in recent years. The dynamic complexity of their cyber-physical systems (CPSs) and their strong inter-dependencies with power systems, are bringing about a significant increase in security problems that may be exploited by attackers. These security holes may, for example, trigger the disintegration of the structural controllability properties due to the problem of non-locality, affecting, sooner or later, the provision of the essential services to end-users. One way to address these situations could be through automatic checkpoints in charge of inspecting the healthy status of the control network and its critical nature. This inspection can be subject to special mechanisms composed of trustworthy cyberphysical elements capable of detecting structural changes in the control and activating restoration procedures with support for warning. This is precisely the aim of this paper, which presents a CPSs-based checkpoint model with the capacity to manage heterogeneous replications that help ensure data redundancy, thereby guaranteeing the validity of the checkpoints. As a support to this study, a theoretical and practical analysis is addressed to show the functionality of the approach in real contexts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NAFMONET2018,

title = {Crowdsourcing analysis in 5G IoT: Cybersecurity Threats and Mitigation},

author = {Ana Nieto and Antonio Acien and Gerardo Fernandez},

url = {/wp-content/papers/NAFMONET2018.pdf},

doi = {10.1007/s11036-018-1146-4},

issn = {1383-469X},

year  = {2018},

date = {2018-10-01},

urldate = {2018-10-01},

journal = {Mobile Networks and Applications (MONET)},

pages = {881-889},

publisher = {Springer US},

abstract = {underlineCrowdsourcing can be a powerful weapon against underlinecyberattacks in underline5G networks. In this paper we analyse this idea in detail, starting from the use cases in underlinecrowdsourcing focused on security, and highlighting those areas of a underline5G ecosystem where underlinecrowdsourcing could be used to mitigate local and remote attacks, as well as to discourage criminal activities and underlinecybercriminal behaviour. We pay particular attention to the capillary network, where an infinite number of underlineIoT objects coexist. The analysis is made considering the different participants in a underline5G underlineIoT ecosystem.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hiroshi18IoT,

title = {Feasibility of Societal Model for Securing Internet of Things},

author = {Hiroshi Tsunoda and Rodrigo Roman and Javier Lopez and Glenn Mansfield Keeni},

url = {/wp-content/papers/Hiroshi18IoT.pdf

http://www.itiis.org/digital-library/manuscript/2082},

doi = {10.3837/tiis.2018.08.003},

issn = {1976-7277},

year  = {2018},

date = {2018-08-01},

urldate = {2018-08-01},

journal = {KSII Transactions on Internet and Information Systems},

volume = {12},

number = {8},

pages = {3567-3588},

publisher = {KSII},

abstract = {In the Internet of Things (IoT) concept, devices communicate autonomously with applications in the Internet. A significant aspect of IoT that makes it stand apart from present-day networked devices and applications is a) the very large number of devices, produced by diverse makers and used by an even more diverse group of users; b) the applications residing and functioning in what were very private sanctums of life e.g. the car, home, and the people themselves. Since these diverse devices require high-level security, an operational model for an IoT system is required, which has built-in security. We have proposed the societal model as a simple operational model. The basic concept of the model is borrowed from human society \textendash there will be infants, the weak and the handicapped who need to be protected by guardians. This natural security mechanism works very well for IoT networks which seem to have inherently weak security mechanisms. In this paper, we discuss the requirements of the societal model and examine its feasibility by doing a proof-of-concept implementation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{transactionInformaticsSG2018,

title = {A Resilient Architecture for the Smart Grid},

author = {Javier Lopez and Juan E. Rubio and Cristina Alcaraz},

url = {/wp-content/papers/transactionInformaticsSG2018.pdf},

doi = {10.1109/TII.2018.2826226},

issn = {1551-3203},

year  = {2018},

date = {2018-08-01},

urldate = {2018-08-01},

journal = {IEEE Transactions on Industrial Informatics},

volume = {14},

pages = {3745-3753},

publisher = {IEEE},

abstract = {The Smart Grid offers many benefits due to the bidirectional communication between the users and the utility company, which makes it possible to perform a fine-grain consumption metering. This can be used for Demand Response purposes with the generation and delivery of electricity in real time. It is essential to rapidly anticipate high peaks of demand or potential attacks, so as to avoid power outages and denial of service, while effectively supplying consumption areas. In this paper, we propose a novel architecture where cloud computing resources are leveraged (and tested in practice) to enable, on the one hand, the consumption prediction through time series forecasting, as well as load balancing to uniformly distribute the demand over a set of available generators. On the other and, it also allows the detection of connectivity losses and intrusions within the control network by using controllability concepts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RomanIoT18,

title = {Evolution and Trends in the Security of the Internet of Things},

author = {Rodrigo Roman and Javier Lopez and Stefanos Gritzalis},

url = {/wp-content/papers/RomanIoT18.pdf

https://ieeexplore.ieee.org/document/8423133/},

doi = {10.1109/MC.2018.3011051},

issn = {0018-9162},

year  = {2018},

date = {2018-07-01},

urldate = {2018-07-01},

journal = {IEEE Computer},

volume = {51},

pages = {16-25},

publisher = {IEEE Computer Society},

address = {New Jersey, USA},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{IonnaisPanosMihalisAlcarazLopez2018,

title = {Survey of IoT-enabled Cyberattacks: Assessing Attack Paths to Critical Infrastructures and Services},

author = {Ioannis Stellios and Panayiotis Kotzanikolaou and Mihalis Psarakis and Cristina Alcaraz and Javier Lopez},

url = {https://ieeexplore.ieee.org/document/8410404},

doi = {10.1109/COMST.2018.2855563},

issn = {1553-877X},

year  = {2018},

date = {2018-07-01},

urldate = {2018-07-01},

journal = {IEEE Communications Surveys and Tutorials},

volume = {20},

pages = {3453-3495},

publisher = {IEEE},

abstract = {As the deployment of Internet of Things (IoT) is experiencing an exponential growth, it is no surprise that many recent cyber attacks are IoT-enabled: The attacker initially exploits some vulnerable IoT technology as a first step towards compromising a critical system that is connected, in some way, with the IoT. For some sectors, like industry, smart grids, transportation and medical services, the significance of such attacks is obvious, since IoT technologies are part of critical backend systems. However, in sectors where IoT is usually at the enduser side, like smart homes, such attacks can be underestimated, since not all possible attack paths are examined. In this paper we survey IoT-enabled cyber attacks, found in all application domains since 2010. For each sector, we emphasize on the latest, verified IoT-enabled attacks, based on known real-world incidents and published proof-of-concept attacks. We methodologically analyze representative attacks that demonstrate direct, indirect and subliminal attack paths against critical targets. Our goal is threefold: (i) To assess IoT-enabled cyber attacks in a risk-like approach, in order to demonstrate their current threat landscape; (ii) To identify hidden and subliminal IoT-enabled attack paths against critical infrastructures and services, and (iii) To examine mitigation strategies for all application domains.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{cazorla2016cyber,

title = {Cyber Stealth Attacks in Critical Information Infrastructures},

author = {Lorena Cazorla and Cristina Alcaraz and Javier Lopez},

url = {/wp-content/papers/cazorla2016cyber.pdf

http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=7445136\&isnumber=8350419},

doi = {10.1109/JSYST.2015.2487684},

issn = {1932-8184},

year  = {2018},

date = {2018-06-01},

urldate = {2018-06-01},

journal = {IEEE Systems Journal},

volume = {12},

pages = {1778-1792},

publisher = {IEEE},

abstract = {Current Critical Infrastructures (CIs) are complex interconnected industrial systems that, in recent years, have incorporated information and communications technologies such as connection to the Internet and commercial off-the-shelf components. This makes them easier to operate and maintain, but exposes them to the threats and attacks that inundate conventional networks and systems. This paper contains a comprehensive study on the main stealth attacks that threaten CIs, with a special focus on Critical Information Infrastructures (CIIs). This type of attack is characterized by an adversary who is able to finely tune his actions to avoid detection while pursuing his objectives. To provide a complete analysis of the scope and potential dangers of stealth attacks we determine and analyze their stages and range, and we design a taxonomy to illustrate the threats to CIs, offering an overview of the applicable countermeasures against these attacks. From our analysis we understand that these types of attacks, due to the interdependent nature of CIs, pose a grave danger to critical systems where the threats can easily cascade down to the interconnected systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2018a,

title = {Cloud-Assisted Dynamic Resilience for Cyber-Physical Control Systems},

author = {Cristina Alcaraz},

url = {/wp-content/papers/Alcaraz2018a.pdf

http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=\&arnumber=8304395\&isnumber=8304374},

doi = {10.1109/MWC.2018.1700231},

issn = {1536-1284},

year  = {2018},

date = {2018-02-01},

urldate = {2018-02-01},

journal = {IEEE Wireless Communications},

volume = {25},

number = {1},

pages = {76-82},

publisher = {IEEE},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nrlSensors2018,

title = {IoT-Forensics meets Privacy: Towards Cooperative Digital Investigations},

author = {Ana Nieto and Ruben Rios and Javier Lopez},

url = {/wp-content/papers/nrlSensors2018.pdf

http://www.mdpi.com/1424-8220/18/2/492},

doi = {10.3390/s18020492},

issn = {1424-8220},

year  = {2018},

date = {2018-02-01},

urldate = {2018-02-01},

journal = {Sensors},

volume = {18},

number = {492},

publisher = {MDPI},

abstract = {IoT-Forensics is a novel paradigm for the acquisition of electronic evidence whose operation is conditioned by the peculiarities of the Internet of Things (IoT) context. As a branch of computer forensics, this discipline respects the most basic forensic principles of preservation, traceability, documentation, and authorization. The digital witness approach also promotes such principles in the context of the IoT while allowing personal devices to cooperate in digital investigations by voluntarily providing electronic evidence to the authorities. However, this solution is highly dependent on the willingness of citizens to collaborate and they may be reluctant to do so if the sensitive information within their personal devices is not sufficiently protected when shared with the investigators. In this paper, we provide the digital witness approach with a methodology that enables citizens to share their data with some privacy guarantees. We apply the PRoFIT methodology, originally defined for IoT-Forensics environments, to the digital witness approach in order to unleash its full potential. Finally, we show the feasibility of a PRoFIT-compliant digital witness with two use cases.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{LOPEZ201846,

title = {Access control for cyber-physical systems interconnected to the cloud},

author = {Javier Lopez and Juan E. Rubio},

url = {/wp-content/papers/LOPEZ201846.pdf

http://www.sciencedirect.com/science/article/pii/S1389128618300501},

doi = {10.1016/j.comnet.2018.01.037},

issn = {1389-1286},

year  = {2018},

date = {2018-01-01},

urldate = {2018-01-01},

journal = {Computer Networks},

volume = {134},

pages = {46 - 54},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{RomanFog16,

title = {Mobile edge computing, Fog et al.: A survey and analysis of security threats and challenges},

author = {Rodrigo Roman and Javier Lopez and Masahiro Mambo},

url = {/wp-content/papers/RomanFog16.pdf

https://authors.elsevier.com/c/1VmhQ,3q5xKgZZ},

doi = {10.1016/j.future.2016.11.009},

issn = {0167-739X},

year  = {2018},

date = {2018-01-01},

urldate = {2018-01-01},

journal = {Future Generation Computer Systems},

volume = {78},

pages = {680-698},

publisher = {Elsevier},

abstract = {For various reasons, the cloud computing paradigm is unable to meet certain requirements (e.g. low latency and jitter, context awareness, mobility support) that are crucial for several applications (e.g. vehicular networks, augmented reality). To fulfil these requirements, various paradigms, such as fog computing, mobile edge computing, and mobile cloud computing, have emerged in recent years. While these edge paradigms share several features, most of the existing research is compartmentalised; no synergies have been explored. This is especially true in the field of security, where most analyses focus only on one edge paradigm, while ignoring the others. The main goal of this study is to holistically analyse the security threats, challenges, and mechanisms inherent in all edge paradigms, while highlighting potential synergies and venues of collaboration. In our results, we will show that all edge paradigms should consider the advances in other paradigms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ruben2017trust,

title = {Modelling Privacy-Aware Trust Negotiations},

author = {Ruben Rios and Carmen Fernandez-Gago and Javier Lopez},

url = {/wp-content/papers/Ruben2017trust.pdf},

doi = {10.1016/j.cose.2017.09.015},

issn = {0167-4048},

year  = {2018},

date = {2018-01-01},

urldate = {2018-01-01},

journal = {Computers \& Security},

volume = {77},

pages = {773-789},

publisher = {Elsevier},

abstract = {Trust negotiations are mechanisms that enable interaction between previously unknown users. After exchanging various pieces of potentially sensitive information, the participants of a negotiation can decide whether or not to trust one another. Therefore, trust negotiations bring about threats to personal privacy if not carefully considered. This paper presents a framework for representing trust negotiations in the early phases of the Software Development Life Cycle (SDLC). The framework can help software engineers to determine the most suitable policies for the system by detecting conflicts between privacy and trust requirements. More precisely, we extend the SI* modelling language and provide a set of predicates for defining trust and privacy policies and a set of rules for describing the dynamics of the system based on the established policies. The formal representation of the model facilitates its automatic verification. The framework has been validated in a distributed social network scenario for connecting drivers with potential passengers willing to share a journey.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{jaime2017,

title = {Interdisciplinarity in practice: Challenges and benefits for privacy research},

author = {Daniel Le M\'{e}tayer, Mathias Bossuet, Fanny Coudert, Claire Gayrel, Francisco Jaime, Christophe Jouvray, Antonio Kung, Zhendong Ma, Antonio Ma\~{n}a},

editor = {Elsevier},

doi = {10.1016/j.clsr.2017.05.020},

year  = {2017},

date = {2017-12-09},

urldate = {2017-12-09},

journal = {Computer Law \& Security Review},

volume = {33},

issue = {6},

pages = {864-869},

abstract = {The goal of this paper is to draw the lessons learned from a project that involved security systems engineers, computer scientists, lawyers and social scientists. Since one of the goals of the project was to propose actual solutions following the privacy by design approach, its aim was to go beyond multidisciplinarity and build on the variety of expertise available in the consortium to follow a true interdisciplinary approach. We present the challenges before describing the solutions adopted by the project to meet them and the outcomes and benefits of the approach. We conclude with some lessons to be drawn from this experience and recommendations for future interdisciplinary projects.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NietNLS15,

title = {Dynamic Knowledge-based Analysis in non-Secure 5G Green Environments using Contextual Data},

author = {Ana Nieto and Nikolaos Nomikos and Javier Lopez and Charalambos Skianis},

url = {/wp-content/papers/NietNLS15.pdf},

doi = {10.1109/JSYST.2015.2477782},

issn = {1932-8184},

year  = {2017},

date = {2017-12-01},

urldate = {2017-12-01},

journal = {IEEE Systems Journal},

volume = {11},

number = {99},

pages = {2479-2489},

publisher = {IEEE},

abstract = {The growing number of parameters in heteroge- neous networks, as is the case of the emphfifth generation (5G) Green networks, greatly complicates the analysis of the emphSecurity and Quality of Service Tradeoff (SQT). However, studying these types of relationships is crucial in Future Internet scenarios to prevent potential points of failure and to enhance the use of limited resources, increasing the user’s experience. Therefore, it is fundamental to provide tools and models for training, so that the users understand these dependencies and solve them prior to deploying new solutions. In this paper, a Recommendation System for SQT (SQT-RS) is deployed in 5G Green systems, considering the particular case of relay networks and the impact of eavesdropping and jamming contexts on the models generated by the user, aided by SQT-RS. With this goal in mind, we provide a component for the user to automatically select specific contexts based on 5G Green capabilities.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz:2017:IJCIS,

title = {Resilient Industrial Control Systems based on Multiple Redundancy},

author = {Cristina Alcaraz},

doi = {10.1504/IJCIS.2017.10009287},

issn = {1741-8038},

year  = {2017},

date = {2017-11-01},

urldate = {2017-11-01},

journal = {International Journal of Critical Infrastructures (IJCIS)},

volume = {13},

number = {2/3},

pages = {278 - 295},

publisher = {Inderscience Publisher},

address = {London, UK},

abstract = {The incessant search for cost-effective recovery solutions for structural controllability has led to one of the most challenging research areas within the field of critical infrastructure protection. The resilience of large heterogeneous distributions, like industrial control scenarios, is proving to be a complicated mission due to the inherent non-locality problems of structural controllability and its susceptibility to advanced threats. To address these issues, this paper proposes a new repair approach based on multiple redundant pathways and the lessons learnt from the work presented in [1]. From [1], we have adapted the local measures, to combine them with each of the five strategies of remote reconnection described in this paper. To validate the sustainability of the combined approaches, two practical case studies are presented here, showing that a local dependence on a brother driver node together with remote dependence is enough to reach optimal states in linear times.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alcaraz2017COSE,

title = {Resilient Interconnection in Cyber-Physical Control Systems},

author = {Cristina Alcaraz and Javier Lopez and Kim-Kwang Raymond Choo},

url = {/wp-content/papers/Alcaraz2017COSE.pdf

http://www.sciencedirect.com/science/article/pii/S0167404817300573},

doi = {10.1016/j.cose.2017.03.004},

issn = {0167-4048},

year  = {2017},

date = {2017-11-01},

urldate = {2017-11-01},

journal = {Computers \& Security},

volume = {71},

pages = {2-14},

publisher = {Elsevier},

abstract = {Secure interconnection between multiple cyber-physical systems has become a fundamental requirement in many critical infrastructures, where security may be centralized in a few nodes of the system. These nodes could, for example, have the mission of addressing the authorization services required for access in highlyrestricted remote substations. For this reason, the main aim of this paper is to unify all these features, together with the resilience measures so as to provide control at all times under a limited access in the field and avoid congestion. Concretely, we present here an optimal reachability-based restoration approach, capable of restoring the structural control in linear times taking into account: structural controllability, the supernode theory, the good practices of the IEC-62351 standard and the contextual conditions. For context management, a new attribute is specified to provide a more complete authorization service based on a practical policy, role and attribute-based access control (PBAC + RBAC + ABAC). To validate the approach, two case studies are also discussed under two strategic adversarial models.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lopez2017iotpriv,

title = {Evolving privacy: From sensors to the Internet of Things},

author = {Javier Lopez and Ruben Rios and Feng Bao and Guilin Wang},

url = {/wp-content/papers/Lopez2017iotpriv.pdf},

doi = {10.1016/j.future.2017.04.045},

issn = {0167-739X},

year  = {2017},

date = {2017-10-01},

urldate = {2017-10-01},

journal = {Future Generation Computer Systems},

volume = {75},

pages = {46\textendash57},

publisher = {Elsevier},

abstract = {The Internet of Things (IoT) envisions a world covered with billions of smart, interacting things capable of offering all sorts of services to near and remote entities. The benefits and comfort that the IoT will bring about are undeniable, however, these may come at the cost of an unprecedented loss of privacy. In this paper we look at the privacy problems of one of the key enablers of the IoT, namely wireless sensor networks, and analyse how these problems may evolve with the development of this complex paradigm. We also identify further challenges which are not directly associated with already existing privacy risks but will certainly have a major impact in our lives if not taken into serious consideration.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{rubiorecommender17,

title = {Recommender System for Privacy-Preserving Solutions in Smart Metering},

author = {Juan E. Rubio and Cristina Alcaraz and Javier Lopez},

url = {/wp-content/papers/rubiorecommender17.pdf},

issn = {1574-1192},

year  = {2017},

date = {2017-10-01},

urldate = {2017-10-01},

journal = {Pervasive and Mobile Computing},

volume = {41},

pages = {205-218},

publisher = {Pervasive and Mobile Computing},

abstract = {Nowadays, Smart Grid is envisaged to provide several benefits to both customers and grid operators. However, Smart Meters introduce many privacy issues if consumption data is analysed. In this paper we analyse the main techniques that address privacy when collecting electricity readings. In addition to privacy, it is equally important to preserve efficiency to carry on with monitoring operations, so further control requirements and communication protocols are also studied. Our aim is to provide guidance to installers who intend to integrate such mechanisms on the grid, presenting an expert system to recommend an appropriate deployment strategy.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nunez2017proxy,

title = {Proxy Re-Encryption: Analysis of Constructions and its Application to Secure Access Delegation},

author = {David Nu\~{n}ez and Isaac Agudo and Javier Lopez},

url = {/wp-content/papers/nunez2017proxy.pdf},

doi = {10.1016/j.jnca.2017.03.005},

issn = {1084-8045},

year  = {2017},

date = {2017-06-01},

urldate = {2017-06-01},

journal = {Journal of Network and Computer Applications},

volume = {87},

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.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{lopez2017ecn,

title = {Protecting Industry 4.0 against Advanced Persistent Threats},

author = {Javier Lopez and Cristina Alcaraz and Jes\'{u}s Rodriguez and Rodrigo Roman and Juan E. Rubio},

url = {/wp-content/papers/lopez2017ecn.pdf},

year  = {2017},

date = {2017-03-01},

urldate = {2017-03-01},

journal = {European CIIP Newsletter},

volume = {11},

number = {1},

pages = {27-29},

publisher = {European CIIP Newsletter},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{AlcarazLopezWolthusen2017,

title = {OCPP Protocol: Security Threats and Challenges},

author = {Cristina Alcaraz and Javier Lopez and Stephen Wolthusen},

url = {/wp-content/papers/AlcarazLopezWolthusen2017.pdf},

doi = {10.1109/TSG.2017.2669647},

issn = {1949-3053},

year  = {2017},

date = {2017-02-01},

urldate = {2017-02-01},

journal = {IEEE Transactions on Smart Grid},

volume = {8},

pages = {2452 - 2459},

publisher = {IEEE},

abstract = {One benefit postulated for the adoption of Electric Vehicles (EVs) is their ability to act as stabilizing entities in smart grids through bi-directional charging, allowing local or global smoothing of peaks and imbalances. This benefit, however, hinges indirectly on the reliability and security of the power flows thus achieved. Therefore this paper studies key security properties of the alreadydeployed Open Charge Point Protocol (OCPP) specifying communication between charging points and energy management systems. It is argued that possible subversion or malicious endpoints in the protocol can also lead to destabilization of power networks. Whilst reviewing these aspects, we focus, from a theoretical and practical standpoint, on attacks that interfere with resource reservation originating with the EV, which may also be initiated by a man in the middle, energy theft or fraud. Such attacks may even be replicated widely, resulting in over- or undershooting of power network provisioning, or the (total/partial) disintegration of the integrity and stability of power networks.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fer_IS17,

title = {Modelling Trust Dynamics in the Internet of Things},

author = {Carmen Fernandez-Gago and Francisco Moyano and Javier Lopez},

url = {/wp-content/papers/Fer_IS17.pdf},

doi = {10.1016/j.ins.2017.02.039},

issn = {0020-0255},

year  = {2017},

date = {2017-01-01},

urldate = {2017-01-01},

journal = {Information Sciences},

volume = {396},

pages = {72-82},

publisher = {Elsevier},

abstract = {The Internet of Things (IoT) is a paradigm based on the interconnection of everyday objects. It is expected that the ‘things’ involved in the IoT paradigm will have to interact with each other, often in uncertain conditions. It is therefore of paramount importance for the success of IoT that there are mechanisms in place that help overcome the lack of certainty. Trust can help achieve this goal. In this paper, we introduce a framework that assists developers in including trust in IoT scenarios. This framework takes into account trust, privacy and identity requirements as well as other functional requirements derived from IoT scenarios to provide the different services that allow the inclusion of trust in the IoT.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nrlSIC16,

title = {Testificaci\'{o}n Digital},

author = {Ana Nieto and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/nrlSIC16.pdf

https://revistasic.es/index.php?option=com_content\&view=article\&id=1713\&Itemid=1498},

issn = {1136-0623},

year  = {2016},

date = {2016-11-01},

urldate = {2016-11-01},

journal = {Revista SIC},

volume = {122},

pages = {94-98},

publisher = {Ediciones CODA},

abstract = {El creciente n\'{u}mero de dispositivos interconectados trae consigo problemas de seguridad bien conocidos; por ejemplo, aquellos debidos a las vulnerabilidades en protocolos muy diversos \textendashmuchos de ellos propietarios\textendash y al factor de error humano introducido por los usuarios. Sin embargo, cabe preguntarse c\'{o}mo podemos usar el despliegue de tales dispositivos en beneficio de la ciberseguridad. En el proyecto IoTest se est\'{a} desarrollando una soluci\'{o}n, el Testigo Digital, que permitir\'{a} a los dispositivos personales con arquitectura de seguridad embebida reaccionar ante ataques virtuales, protegi\'{e}ndonos de los ciberataques emergentes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nunez2016application,

title = {On the Application of Generic CCA-Secure Transformations to Proxy Re-Encryption},

author = {David Nu\~{n}ez and Isaac Agudo and Javier Lopez},

url = {/wp-content/papers/nunez2016application.pdf},

doi = {10.1002/sec.1434},

issn = {1939-0114},

year  = {2016},

date = {2016-08-01},

urldate = {2016-08-01},

journal = {Security and Communication Networks},

volume = {9},

pages = {1769-1785},

publisher = {Wiley},

abstract = {Several generic methods exist for achieving chosen-ciphertext attack (CCA)-secure public-key encryption schemes from weakly secure cryptosystems, such as the Fujisaki\textendashOkamoto and REACT transformations. In the context of proxy re-encryption (PRE), it would be desirable to count on analogous constructions that allow PRE schemes to achieve better security notions. In this paper, we study the adaptation of these transformations to proxy re-encryption and find both negative and positive results. On the one hand, we show why it is not possible to directly integrate these transformations with weakly secure PRE schemes because of general obstacles coming from both the constructions themselves and the security models, and we identify 12 PRE schemes that exhibit these problems. On the other hand, we propose an extension of the Fujisaki\textendashOkamoto transformation for PRE, which achieves a weak form of CCA security in the random oracle model, and we describe the sufficient conditions for applying it},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nunez2016eliciting,

title = {Eliciting Metrics for Accountability of Cloud Systems},

author = {David Nu\~{n}ez and Carmen Fernandez-Gago and Jes\'{u}s Luna},

url = {/wp-content/papers/nunez2016eliciting.pdf},

doi = {10.1016/j.cose.2016.07.003},

issn = {0167-4048},

year  = {2016},

date = {2016-08-01},

urldate = {2016-08-01},

journal = {Computers \& Security},

volume = {62},

pages = {149-164},

publisher = {Elsevier},

abstract = {Cloud computing provides enormous business opportunities, but at the same time is a complex and challenging paradigm. The major concerns for users adopting the cloud are the loss of control over their data and the lack of transparency. Providing accountability to cloud systems could foster trust in the cloud and contribute toward its adoption. Assessing how accountable a cloud provider is becomes then a key issue, not only for demonstrating accountability, but to build it. To this end, we need techniques to measure the factors that influence on accountability. In this paper, we provide a methodology to elicit metrics for accountability in the cloud, which consists of three different stages. Since the nature of accountability at- tributes is very abstract and complex, in the first stage we perform a conceptual analysis of the accountability attributes in order to decompose them into concrete practices and mechanisms. Then, we analyze relevant control frameworks designed to guide the implementation of security and privacy mechanisms, and use them to identify measurable factors, related to the practices and mechanisms defined earlier. Lastly, specific metrics for these factors are derived. We also provide some strategies that we consider relevant for the empirical validation of the elicited accountability metrics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ercim-nrl16,

title = {Digital Witness: Digital Evidence Management Framework for the Internet of Things},

author = {Ana Nieto and Rodrigo Roman and Javier Lopez},

url = {http://ercim-news.ercim.eu/images/stories/EN106/EN106-web.pdf},

issn = {0926-4981},

year  = {2016},

date = {2016-07-01},

urldate = {2016-07-01},

journal = {ERCIM News},

number = {106},

pages = {9-9},

publisher = {ERCIM EEIG},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{JNCA16,

title = {A Model-driven Approach for Engineering Trust and Reputation into Software Services},

author = {Francisco Moyano and Carmen Fernandez-Gago and Javier Lopez},

url = {/wp-content/papers/JNCA16.pdf},

issn = {1084-8045},

year  = {2016},

date = {2016-04-01},

urldate = {2016-04-01},

journal = {Journal of Network and Computer Applications},

volume = {69},

pages = {134-151},

publisher = {Elsevier},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ieeenet16-nrl,

title = {Digital Witness: Safeguarding Digital Evidence by using Secure Architectures in Personal Devices},

author = {Ana Nieto and Rodrigo Roman and Javier Lopez},

url = {/wp-content/papers/ieeenet16-nrl.pdf

http://ieeexplore.ieee.org/document/7764297/$#$full-text-section},

doi = {10.1109/MNET.2016.1600087NM},

issn = {0890-8044},

year  = {2016},

date = {2016-01-01},

urldate = {2016-01-01},

journal = {IEEE Network},

pages = {12-19},

publisher = {IEEE Communications Society},

abstract = {Personal devices contain electronic evidence associated with the behaviour of their owners and other devices in their environment, which can help clarify the facts of a cyber-crime scene. These devices are usually analysed as containers of proof. However, it is possible to harness the boom of personal devices to define the concept of digital witnesses, where personal devices are able to actively acquire, store, and transmit digital evidence to an authorised entity, reliably and securely. This article introduces this novel concept, providing a preliminary analysis on the management of digital evidence and the technologies that can be used to implement it with security guarantees in IoT environments. Moreover, the basic building blocks of a digital witness are defined.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{alcaraz2016POL,

title = {Policy Enforcement System for Secure Interoperable Control in Distributed Smart Grid Systems},

author = {Cristina Alcaraz and Javier Lopez and Stephen Wolthusen},

url = {/wp-content/papers/alcaraz2016POL.pdf},

issn = {1084-8045},

year  = {2016},

date = {2016-01-01},

urldate = {2016-01-01},

journal = {Journal of Network and Computer Applications},

volume = {59},

pages = {301\textendash314},

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 emphrole-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 emphstructural controllability theory. The interconnection of these distributions is subject to a network architecture based on the concept of the emphsupernode 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 emphinteroperability.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NL-COMCOM15,

title = {Contextualising Heterogeneous Information in Unified Communications with Security Restrictions},

author = {Ana Nieto and Javier Lopez},

url = {/wp-content/papers/NL-COMCOM15.pdf

http://www.sciencedirect.com/science/article/pii/S0140366415002534},

doi = {10.1016/j.comcom.2015.07.015},

issn = {0140-3664},

year  = {2015},

date = {2015-09-01},

urldate = {2015-09-01},

journal = {Computer Communications},

volume = {68},

pages = {33-46},

publisher = {Elsevier},

abstract = {The lack of abstraction in a growing semantic, virtual and abstract world poses new challenges for assessing security and QoS tradeoffs. For example, in Future Internet scenarios, where Unified Communications (UC) will take place, being able to predict the final devices that will form the network is not always possible. Without this information the analysis of the security and QoS tradeoff can only be based on partial information to be completed when more information about the environment is available. In this paper, we extend the description of context-based parametric relationship model, providing a tool for assessing the security and QoS tradeoff (SQT) based on interchangeable contexts. Our approach is able to use the heterogeneous information produced by scenarios where UC is present.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}