Optimal Information-Theoretic Wireless Location Verification

We develop a new Location Verification System (LVS) focussed on network-based Intelligent Transport Systems and vehicular ad hoc networks. The algorithm we develop is based on an information-theoretic framework which uses the received signal strength (RSS) from a network of base-stations and the claimed position. Based on this information we derive the optimal decision regarding the verification of the user's location. Our algorithm is optimal in the sense of maximizing the mutual information between its input and output data. Our approach is based on the practical scenario in which a non-colluding malicious user some distance from a highway optimally boosts his transmit power in an attempt to fool the LVS that he is on the highway. We develop a practical threat model for this attack scenario, and investigate in detail the performance of the LVS in terms of its input/output mutual information. We show how our LVS decision rule can be implemented straightforwardly with a performance that delivers near-optimality under realistic threat conditions, with information-theoretic optimality approached as the malicious user moves further from the highway. The practical advantages our new information-theoretic scheme delivers relative to more traditional Bayesian verification frameworks are discussed.Comment: Corrected typos and introduced new threat model

"On the Road" - Reflections on the Security of Vehicular Communication Systems

Vehicular communication (VC) systems have recently drawn the attention of industry, authorities, and academia. A consensus on the need to secure VC systems and protect the privacy of their users led to concerted efforts to design security architectures. Interestingly, the results different project contributed thus far bear extensive similarities in terms of objectives and mechanisms. As a result, this appears to be an auspicious time for setting the corner-stone of trustworthy VC systems. Nonetheless, there is a considerable distance to cover till their deployment. This paper ponders on the road ahead. First, it presents a distillation of the state of the art, covering the perceived threat model, security requirements, and basic secure VC system components. Then, it dissects predominant assumptions and design choices and considers alternatives. Under the prism of what is necessary to render secure VC systems practical, and given possible non-technical influences, the paper attempts to chart the landscape towards the deployment of secure VC systems

Opportunistic Sensing: Security Challenges for the New Paradigm

We study the security challenges that arise in Opportunistic people-centric sensing, a new sensing paradigm leveraging humans as part of the sensing infrastructure. Most prior sensor-network research has focused on collecting and processing environmental data using a static topology and an application-aware infrastructure, whereas opportunistic sensing involves collecting, storing, processing and fusing large volumes of data related to everyday human activities. This highly dynamic and mobile setting, where humans are the central focus, presents new challenges for information security, because data originates from sensors carried by people— not tiny sensors thrown in the forest or attached to animals. In this paper we aim to instigate discussion of this critical issue, because opportunistic people-centric sensing will never succeed without adequate provisions for security and privacy. To that end, we outline several important challenges and suggest general solutions that hold promise in this new sensing paradigm

AMISEC: Leveraging Redundancy and Adaptability to Secure AmI Applications

Security in Ambient Intelligence (AmI) poses too many challenges due to the inherently insecure nature of wireless sensor nodes. However, there are two characteristics of these environments that can be used effectively to prevent, detect, and confine attacks: redundancy and continuous adaptation. In this article we propose a global strategy and a system architecture to cope with security issues in AmI applications at different levels. Unlike in previous approaches, we assume an individual wireless node is vulnerable. We present an agent-based architecture with supporting services that is proven to be adequate to detect and confine common attacks. Decisions at different levels are supported by a trust-based framework with good and bad reputation feedback while maintaining resistance to bad-mouthing attacks. We also propose a set of services that can be used to handle identification, authentication, and authorization in intelligent ambients. The resulting approach takes into account practical issues, such as resource limitation, bandwidth optimization, and scalability

Novel architectures and strategies for security offloading

Internet has become an indispensable and powerful tool in our modern society. Its ubiquitousness, pervasiveness and applicability have fostered paradigm changes around many aspects of our lives. This phenomena has positioned the network and its services as fundamental assets over which we rely and trust. However, Internet is far from being perfect. It has considerable security issues and vulnerabilities that jeopardize its main core functionalities with negative impact over its players. Furthermore, these vulnerabilities¿ complexities have been amplified along with the evolution of Internet user mobility. In general, Internet security includes both security for the correct network operation and security for the network users and endpoint devices. The former involves the challenges around the Internet core control and management vulnerabilities, while the latter encompasses security vulnerabilities over end users and endpoint devices. Similarly, Internet mobility poses major security challenges ranging from routing complications, connectivity disruptions and lack of global authentication and authorization. The purpose of this thesis is to present the design of novel architectures and strategies for improving Internet security in a non-disruptive manner. Our novel security proposals follow a protection offloading approach. The motives behind this paradigm target the further enhancement of the security protection while minimizing the intrusiveness and disturbance over the Internet routing protocols, its players and users. To accomplish such level of transparency, the envisioned solutions leverage on well-known technologies, namely, Software Defined Networks, Network Function Virtualization and Fog Computing. From the Internet core building blocks, we focus on the vulnerabilities of two key routing protocols that play a fundamental role in the present and the future of the Internet, i.e., the Border Gateway Protocol (BGP) and the Locator-Identifier Split Protocol (LISP). To this purpose, we first investigate current BGP vulnerabilities and countermeasures with emphasis in an unresolved security issue defined as Route Leaks. Therein, we discuss the reasons why different BGP security proposals have failed to be adopted, and the necessity to propose innovative solutions that minimize the impact over the already deployed routing solution. To this end, we propose pragmatic security methodologies to offload the protection with the following advantages: no changes to the BGP protocol, neither dependency on third party information nor on third party security infrastructure, and self-beneficial. Similarly, we research the current LISP vulnerabilities with emphasis on its control plane and mobility support. We leverage its by-design separation of control and data planes to propose an enhanced location-identifier registration process of end point identifiers. This proposal improves the mobility of end users with regards on securing a dynamic traffic steering over the Internet. On the other hand, from the end user and devices perspective we research new paradigms and architectures with the aim of enhancing their protection in a more controllable and consolidated manner. To this end, we propose a new paradigm which shifts the device-centric protection paradigm toward a user-centric protection. Our proposal focus on the decoupling or extending of the security protection from the end devices toward the network edge. It seeks the homogenization of the enforced protection per user independently of the device utilized. We further investigate this paradigm in a mobility user scenario. Similarly, we extend this proposed paradigm to the IoT realm and its intrinsic security challenges. Therein, we propose an alternative to protect both the things, and the services that leverage from them by consolidating the security at the network edge. We validate our proposal by providing experimental results from prof-of-concepts implementations.Internet se ha convertido en una poderosa e indispensable herramienta para nuestra sociedad moderna. Su omnipresencia y aplicabilidad han promovido grandes cambios en diferentes aspectos de nuestras vidas. Este fenómeno ha posicionado a la red y sus servicios como activos fundamentales sobre los que contamos y confiamos. Sin embargo, Internet está lejos de ser perfecto. Tiene considerables problemas de seguridad y vulnerabilidades que ponen en peligro sus principales funcionalidades. Además, las complejidades de estas vulnerabilidades se han ampliado junto con la evolución de la movilidad de usuarios de Internet y su limitado soporte. La seguridad de Internet incluye tanto la seguridad para el correcto funcionamiento de la red como la seguridad para los usuarios y sus dispositivos. El primero implica los desafíos relacionados con las vulnerabilidades de control y gestión de la infraestructura central de Internet, mientras que el segundo abarca las vulnerabilidades de seguridad sobre los usuarios finales y sus dispositivos. Del mismo modo, la movilidad en Internet plantea importantes desafíos de seguridad que van desde las complicaciones de enrutamiento, interrupciones de la conectividad y falta de autenticación y autorización globales. El propósito de esta tesis es presentar el diseño de nuevas arquitecturas y estrategias para mejorar la seguridad de Internet de una manera no perturbadora. Nuestras propuestas de seguridad siguen un enfoque de desacople de la protección. Los motivos detrás de este paradigma apuntan a la mejora adicional de la seguridad mientras que minimizan la intrusividad y la perturbación sobre los protocolos de enrutamiento de Internet, sus actores y usuarios. Para lograr este nivel de transparencia, las soluciones previstas aprovechan nuevas tecnologías, como redes definidas por software (SDN), virtualización de funciones de red (VNF) y computación en niebla. Desde la perspectiva central de Internet, nos centramos en las vulnerabilidades de dos protocolos de enrutamiento clave que desempeñan un papel fundamental en el presente y el futuro de Internet, el Protocolo de Puerta de Enlace Fronterizo (BGP) y el Protocolo de Separación Identificador/Localizador (LISP ). Para ello, primero investigamos las vulnerabilidades y medidas para contrarrestar un problema no resuelto en BGP definido como Route Leaks. Proponemos metodologías pragmáticas de seguridad para desacoplar la protección con las siguientes ventajas: no cambios en el protocolo BGP, cero dependencia en la información de terceros, ni de infraestructura de seguridad de terceros, y de beneficio propio. Del mismo modo, investigamos las vulnerabilidades actuales sobre LISP con énfasis en su plano de control y soporte de movilidad. Aprovechamos la separacçón de sus planos de control y de datos para proponer un proceso mejorado de registro de identificadores de ubicación y punto final, validando de forma segura sus respectivas autorizaciones. Esta propuesta mejora la movilidad de los usuarios finales con respecto a segurar un enrutamiento dinámico del tráfico a través de Internet. En paralelo, desde el punto de vista de usuarios finales y dispositivos investigamos nuevos paradigmas y arquitecturas con el objetivo de mejorar su protección de forma controlable y consolidada. Con este fin, proponemos un nuevo paradigma hacia una protección centrada en el usuario. Nuestra propuesta se centra en el desacoplamiento o ampliación de la protección de seguridad de los dispositivos finales hacia el borde de la red. La misma busca la homogeneización de la protección del usuario independientemente del dispositivo utilizado. Además, investigamos este paradigma en un escenario con movilidad. Validamos nuestra propuesta proporcionando resultados experimentales obtenidos de diferentes experimentos y pruebas de concepto implementados

Novel architectures and strategies for security offloading

Internet has become an indispensable and powerful tool in our modern society. Its ubiquitousness, pervasiveness and applicability have fostered paradigm changes around many aspects of our lives. This phenomena has positioned the network and its services as fundamental assets over which we rely and trust. However, Internet is far from being perfect. It has considerable security issues and vulnerabilities that jeopardize its main core functionalities with negative impact over its players. Furthermore, these vulnerabilities¿ complexities have been amplified along with the evolution of Internet user mobility. In general, Internet security includes both security for the correct network operation and security for the network users and endpoint devices. The former involves the challenges around the Internet core control and management vulnerabilities, while the latter encompasses security vulnerabilities over end users and endpoint devices. Similarly, Internet mobility poses major security challenges ranging from routing complications, connectivity disruptions and lack of global authentication and authorization. The purpose of this thesis is to present the design of novel architectures and strategies for improving Internet security in a non-disruptive manner. Our novel security proposals follow a protection offloading approach. The motives behind this paradigm target the further enhancement of the security protection while minimizing the intrusiveness and disturbance over the Internet routing protocols, its players and users. To accomplish such level of transparency, the envisioned solutions leverage on well-known technologies, namely, Software Defined Networks, Network Function Virtualization and Fog Computing. From the Internet core building blocks, we focus on the vulnerabilities of two key routing protocols that play a fundamental role in the present and the future of the Internet, i.e., the Border Gateway Protocol (BGP) and the Locator-Identifier Split Protocol (LISP). To this purpose, we first investigate current BGP vulnerabilities and countermeasures with emphasis in an unresolved security issue defined as Route Leaks. Therein, we discuss the reasons why different BGP security proposals have failed to be adopted, and the necessity to propose innovative solutions that minimize the impact over the already deployed routing solution. To this end, we propose pragmatic security methodologies to offload the protection with the following advantages: no changes to the BGP protocol, neither dependency on third party information nor on third party security infrastructure, and self-beneficial. Similarly, we research the current LISP vulnerabilities with emphasis on its control plane and mobility support. We leverage its by-design separation of control and data planes to propose an enhanced location-identifier registration process of end point identifiers. This proposal improves the mobility of end users with regards on securing a dynamic traffic steering over the Internet. On the other hand, from the end user and devices perspective we research new paradigms and architectures with the aim of enhancing their protection in a more controllable and consolidated manner. To this end, we propose a new paradigm which shifts the device-centric protection paradigm toward a user-centric protection. Our proposal focus on the decoupling or extending of the security protection from the end devices toward the network edge. It seeks the homogenization of the enforced protection per user independently of the device utilized. We further investigate this paradigm in a mobility user scenario. Similarly, we extend this proposed paradigm to the IoT realm and its intrinsic security challenges. Therein, we propose an alternative to protect both the things, and the services that leverage from them by consolidating the security at the network edge. We validate our proposal by providing experimental results from prof-of-concepts implementations.Internet se ha convertido en una poderosa e indispensable herramienta para nuestra sociedad moderna. Su omnipresencia y aplicabilidad han promovido grandes cambios en diferentes aspectos de nuestras vidas. Este fenómeno ha posicionado a la red y sus servicios como activos fundamentales sobre los que contamos y confiamos. Sin embargo, Internet está lejos de ser perfecto. Tiene considerables problemas de seguridad y vulnerabilidades que ponen en peligro sus principales funcionalidades. Además, las complejidades de estas vulnerabilidades se han ampliado junto con la evolución de la movilidad de usuarios de Internet y su limitado soporte. La seguridad de Internet incluye tanto la seguridad para el correcto funcionamiento de la red como la seguridad para los usuarios y sus dispositivos. El primero implica los desafíos relacionados con las vulnerabilidades de control y gestión de la infraestructura central de Internet, mientras que el segundo abarca las vulnerabilidades de seguridad sobre los usuarios finales y sus dispositivos. Del mismo modo, la movilidad en Internet plantea importantes desafíos de seguridad que van desde las complicaciones de enrutamiento, interrupciones de la conectividad y falta de autenticación y autorización globales. El propósito de esta tesis es presentar el diseño de nuevas arquitecturas y estrategias para mejorar la seguridad de Internet de una manera no perturbadora. Nuestras propuestas de seguridad siguen un enfoque de desacople de la protección. Los motivos detrás de este paradigma apuntan a la mejora adicional de la seguridad mientras que minimizan la intrusividad y la perturbación sobre los protocolos de enrutamiento de Internet, sus actores y usuarios. Para lograr este nivel de transparencia, las soluciones previstas aprovechan nuevas tecnologías, como redes definidas por software (SDN), virtualización de funciones de red (VNF) y computación en niebla. Desde la perspectiva central de Internet, nos centramos en las vulnerabilidades de dos protocolos de enrutamiento clave que desempeñan un papel fundamental en el presente y el futuro de Internet, el Protocolo de Puerta de Enlace Fronterizo (BGP) y el Protocolo de Separación Identificador/Localizador (LISP ). Para ello, primero investigamos las vulnerabilidades y medidas para contrarrestar un problema no resuelto en BGP definido como Route Leaks. Proponemos metodologías pragmáticas de seguridad para desacoplar la protección con las siguientes ventajas: no cambios en el protocolo BGP, cero dependencia en la información de terceros, ni de infraestructura de seguridad de terceros, y de beneficio propio. Del mismo modo, investigamos las vulnerabilidades actuales sobre LISP con énfasis en su plano de control y soporte de movilidad. Aprovechamos la separacçón de sus planos de control y de datos para proponer un proceso mejorado de registro de identificadores de ubicación y punto final, validando de forma segura sus respectivas autorizaciones. Esta propuesta mejora la movilidad de los usuarios finales con respecto a segurar un enrutamiento dinámico del tráfico a través de Internet. En paralelo, desde el punto de vista de usuarios finales y dispositivos investigamos nuevos paradigmas y arquitecturas con el objetivo de mejorar su protección de forma controlable y consolidada. Con este fin, proponemos un nuevo paradigma hacia una protección centrada en el usuario. Nuestra propuesta se centra en el desacoplamiento o ampliación de la protección de seguridad de los dispositivos finales hacia el borde de la red. La misma busca la homogeneización de la protección del usuario independientemente del dispositivo utilizado. Además, investigamos este paradigma en un escenario con movilidad. Validamos nuestra propuesta proporcionando resultados experimentales obtenidos de diferentes experimentos y pruebas de concepto implementados.Postprint (published version

A comprehensive survey of V2X cybersecurity mechanisms and future research paths

Recent advancements in vehicle-to-everything (V2X) communication have notably improved existing transport systems by enabling increased connectivity and driving autonomy levels. The remarkable benefits of V2X connectivity come inadvertently with challenges which involve security vulnerabilities and breaches. Addressing security concerns is essential for seamless and safe operation of mission-critical V2X use cases. This paper surveys current literature on V2X security and provides a systematic and comprehensive review of the most relevant security enhancements to date. An in-depth classification of V2X attacks is first performed according to key security and privacy requirements. Our methodology resumes with a taxonomy of security mechanisms based on their proactive/reactive defensive approach, which helps identify strengths and limitations of state-of-the-art countermeasures for V2X attacks. In addition, this paper delves into the potential of emerging security approaches leveraging artificial intelligence tools to meet security objectives. Promising data-driven solutions tailored to tackle security, privacy and trust issues are thoroughly discussed along with new threat vectors introduced inevitably by these enablers. The lessons learned from the detailed review of existing works are also compiled and highlighted. We conclude this survey with a structured synthesis of open challenges and future research directions to foster contributions in this prominent field.This work is supported by the H2020-INSPIRE-5Gplus project (under Grant agreement No. 871808), the ”Ministerio de Asuntos Económicos y Transformacion Digital” and the European Union-NextGenerationEU in the frameworks of the ”Plan de Recuperación, Transformación y Resiliencia” and of the ”Mecanismo de Recuperación y Resiliencia” under references TSI-063000-2021-39/40/41, and the CHIST-ERA-17-BDSI-003 FIREMAN project funded by the Spanish National Foundation (Grant PCI2019-103780).Peer ReviewedPostprint (published version

Multi-factor Physical Layer Security Authentication in Short Blocklength Communication

Lightweight and low latency security schemes at the physical layer that have recently attracted a lot of attention include: (i) physical unclonable functions (PUFs), (ii) localization based authentication, and, (iii) secret key generation (SKG) from wireless fading coefficients. In this paper, we focus on short blocklengths and propose a fast, privacy preserving, multi-factor authentication protocol that uniquely combines PUFs, proximity estimation and SKG. We focus on delay constrained applications and demonstrate the performance of the SKG scheme in the short blocklength by providing a numerical comparison of three families of channel codes, including half rate low density parity check codes (LDPC), Bose Chaudhuri Hocquenghem (BCH), and, Polar Slepian Wolf codes for n=512, 1024. The SKG keys are incorporated in a zero-round-trip-time resumption protocol for fast re-authentication. All schemes of the proposed mutual authentication protocol are shown to be secure through formal proofs using Burrows, Abadi and Needham (BAN) and Mao and Boyd (MB) logic as well as the Tamarin-prover