The fifth generation of cellular networks (5G) is now a reality which is starting to be implemented, and they are soon to be used in our everyday life, but this scenario has certain particularities that make it sensitive to attacks of different nature. The goal at NICS lab is to provide proactive security solutions for 5G; that is not only be able to provide real-time security solutions, but also be able to prepare the 5G infrastructure to act proactively. This requires defining the security requirements and deploying the basic enablers (e.g. specific software and hardware devices for security tasks) before deploying other security solutions. Thus, an important part of our research is to model different 5G scenarios in realistic simulations which make it possible for us to analyse the potential problems and offer solutions to them.
For example, one of the main concerns is the vulnerability of 5G networks to be taken down by rogue agents that appear to be normal users. 5G networks rely on technologies such as mmWave, which use small interconnected relays operating in EHF (Extremely High Frequency), ranging from 110 to 300 GHz. This means that the wavelength used is really short (from 1mm to 1cm), causing the signal to be vulnerable to interferences, such as rain or buildings, and, therefore, needing additional devices for increasing the radio coverage. These devices are very sensible to jamming and other proximity-based attacks, and other open challenges in different areas. However, to the well-known jamming and eavesdropping attacks, in recent years malware-based attacks has been added to the list of potential threats, as is highlighted in the last ENISA 5G theat landscape report. These new and advanced threats will make it very difficult to stop the attacks in 5G environments before they will be propagated, even towards different layers, causing serious damages to either the infrastructure or the users.
The current research at NICS Lab is focused on three main areas: i) detection and analysis of cross-layer attacks, ii) proactive digital forensics in 5G - and, in particular, how this can be useful to trace proximity-based attacks, and iii) security and QoS tradeoffs.
The Cloud Computing concept appeared as a response to the necessity of bringing computation and storage services following a flexible and on-demand business model. However, from its conception the cloud computing paradigm, and its associated nature of outsourced data management and computation, has bring also some security and privacy problems. Security in cloud computing has been traditionally regarded as one of the major concerns by enterprises and organizations. Moreover, there is no global and harmonized policies for data protection among different countries, which makes interoperability difficult both at legal and technical levels. Trust in the different actors that conform the cloud ecosystem is also a challenging issue, since the cloud model is inherently opaque. All these problems have hindered the adoption of cloud computing.
For example, the problem of accountability (e.g., "who is responsible of the security and proper stewardship of my data in the cloud?") has not a clear answer nowadays, as there is no accountability frameworks for distributed IT services. This leads to difficulty for users to understand, influence and determine how their service providers respond to their obligations. To this matter, NICS participates in the FP7 project A4Cloud, which aims to extend accountability across entire cloud service value chains, covering personal and business sensitive information in the cloud. A4Cloud will create solutions to support users in deciding and tracking how their data is used by cloud service providers.
Computing has become a major focus in many research areas. One of the current trends in cloud computing is the federation of different cloud providers. A federation of clouds would enable local cloud providers (i.e., SMEs) to build business alliances with other cloud providers (possibly scattered around the globe), for offering more competitive solutions. In this direction, NICS is working on the FISICCO project, where we aim to develop and integrate of services for federating and interconnecting cloud computing infrastructures in a secure way, through the extension of existing interconnection architectures and the definition of new connectors. FISICCO can be seen as an extension of existing interconnection architectures, that will lead cloud computing to an upper level of interoperability. Another research area within this project is addressing the problem of privacy and data confidentiality in cloud-based identity services using cryptographic means.
There are different deployment models depending on the level of abstraction used to define the services offered by the Cloud. The lower level, also known as Infrastructure as a Service (IaaS), deals with the hardware and virtualization techniques. How resources communicate in such a distributed setup and how interactions are authenticated is still work in progress. In the PASSIVE project we have worked towards an authentication scheme for applications, users and resources that is suitable for its use in large and highly dynamic deployments such as the Cloud.
Critical (Information) Infrastructures Protection (CIIP/CIP) has become one of the most cutting-edge research areas in recent years. Private and public entities are joining efforts to offer more and more attractive solutions that help governments/industries to protect their infrastructures. Within the CIIP field, we highlight Industry 4.0 by expanding the monitoring capacities of the traditional control systems, commonly known as Supervisory Control and Data Acquisition (SCADA) systems, and allowing the IT-OT (information technology and operation technology) convergence in control domains. Part of this convergence entails the pragmatic adaptation of new paradigms and technologies, among which we stress: Industrial Internet of Things (IIoT), Cyber-Physical Systems and Edge Computing, all capable of processing, rendering and storing large data volume, digitalising processes and addressing new "smart" services to improve the production and distribution costs, economy and society. Although the benefits are evident for the existing critical infrastructures, the technological complexities may hamper the functional processes and bring about multiple types of security risks, which may not help prevent and mitigate advanced attacks, like Advanced Persistent Threats (APTs).
Over the last years, NICS Lab has dedicated part of its time on researching CPS and IIoT security and privacy challenges, providing specific solutions for situation awareness (detection, response and resilience) and secure interconnection of critical federated environments such as Smart Grid utilities. Many of these solutions have been framed within the context of Industry 4.0 (SADCIP, DISS-IIoT) and CIP (though mainly centered on SCADA systems - PISCIS, ATENEA, eCID or CRISIS), as well as part of other critical sectors such as energy (SealedGRID, CAIN, PERSIST, TIGRIS, SECRET, PROTECT-IC), water (FACIES) and health (CYBSEC-TECH). In this sense, thereotical models (structural controllability, Opinion Dynamics), technologies and paradigms (CPS, IIoT, Cloud/Fog), standards (IEC-62351, NIST-7628/800-82) and protocols (Modbus, OCPP, ZigBee PRO, WirelessHART, ISA100.11a) have been broadly considered to provide solid solutions under feasible and flexible specifications.
It is hard to find a globally accepted definition of the term Identity and even harder to precisely define what is understood by Identity Management. User Authentication, Access Control and Privilege Management form the core three aspects of Identity Management that have been the focus of NICS research from the very beginning. With the emergence of the Internet of Services, more and more complex aspects regarding identity have arisen, most of them related with its interoperability. There have been many developments in this field that have derived in the specification of standards for Identity Federation services. Those developments have motivated further research on related areas such as Trust Management and User Privacy.
At NICS we have covered most of the research areas that fall under Identity Management, some of them as a primary focus and some others transversally in the context of another research area. In a national project called PRIVILEGE we focused on the definition of a common framework for privilege management paying special attention to delegation and how to provide anonymity in attribute certificates. The work developed by NICS at the European project SPIKE focuses on the development of agile solutions for the authentication, authorisation and identity federation for allied companies. In the PICOS European project we concentrated on the privacy issues arising from the use of social community services.
Additionally, we have worked on the application of identity management systems in Future Internet scenarios. Cloud Computing promises a plethora of services in the cloud, among them there exists an opportunity to externalise the Identity Management service bringing great security and privacy concerns. Some solutions to these problems have been provided within the FISSICO project. Besides user authentication, we worked towards the authentication and authorisation of applications and resources within the PASSIVE and OSAMI projects. Another core element of the Future Internet are smart environments where the user interacts with objects surrounding him. NICS has also developed a privacy-aware user authentication solution that allows users to access proximity-based services without disclosing personally identifiable information.
The vision of the Internet of Things (IoT) has evolved from its core premise (“a worldwide network of interconnected entities”) in a multitude of ways. The ‘things’ themselves now encompass not only RFID tags and sensor devices, but also complex systems like connected cars, consumer devices (TVs and cameras), and even basic facilities (fridges, doors). Moreover, the concept of the IoT itself can be instantiated in multiple ways, such as the Industrial Internet of Things (IIoT) and the Internet of Everything; and is also related to many paradigms, such as Cyber-Physical Systems and Fog/Edge Computing. Still, there will be always various security challenges that need to be addressed: from protocol and network security to entity authentication, anomaly detection, privacy, and trust [Roman2018]. In fact, as we pointed out in our firsts analyses of this subject (SPRINT, NESSoS), security and privacy are of paramount importance for the successful adoption of this new paradigm: in a world with potentially billions of things, the number of attack vectors available to malicious attackers will be staggering. Moreover, such attacks will target our everyday things (cars, appliances, etc) - and our everyday lives.
Due to these reasons, over the last few years NICS has worked on various IoT security and privacy challenges. Some of these challenges, such as threat detection (intrusion detection, IoT honeypots), trust management, entity anonymity, and security infrastructures, are being studied in the context of Industry 4.0 (DISS-IoT, SADCIP), and Edge Computing (SMOG), among other areas like digital forensics and 5G (IoTest) and smart transportation (EV-UrbanLab). Other contributions include protection mechanisms such as secure communications, entity authentication, security and quality of service, and anomaly detection, which were studied in the context of smart metering and smart street lighting (TIGRIS), smart cities (ENVIA, BIO-VIA), e-Health [Najera12], and intelligent transport systems (DEPHISIT).
The network communication grounds (and among them, distance and lack of trust) makes translation of paper-based procedures to networked digital ones not a trivial task. Thus, in order to realise security in Internet (or any other networked including mobile) applications, special protocols are needed to ensure that any dispute could be solved between users if the network fails or an entity misbehaves. In the computer security field, these protocols are known as non-repudiation protocols, a key element for the provision of the non-repudiation service as standardised by the ITU-T X.813.
Research oriented to non-repudiation protocols has been active since the beginning of this millennium; considering in most occasions only two parties as the players of the protocol design scenario. The work in NICS has been focused in multi-party non-repudiation protocols analysis, design, simulation and implementation. This work covers from general designs and analysis to application-driven design and implementation (as the non-repudiation supported OMA-DRM framework developed in the UBISEC project). At the same time, multi-party non repudiation protocols serve as the basis for other value-added services like Certified Electronic Mail and Contract Signing protocols. In this direction NICS has designed optimal multi-party protocols and studied their properties compatibility.
Radio Frequency IDentification (RFID) technology provides a seamless link between the items of the physical world and the information system including identification, information and computation capabilities. Due to this, it is being adopted in several sectors and is expected to be a key technology in the upcoming Internet of Things. However, its features turn it into a double-edge sword which arise several privacy and anonymity threats which combined with its extremely constrained computation and communication capabilities has turned RFID security into a relevant and complex research field.
From our group, we have and are working on the secure integration of RFID technology in a variety of scenarios. Up to now, our research has focused in two main scenarios: personal documentation and healthcare environments, both supported by research projects. In the context of the IDENTICA project, we focused on the secure integration of RFID technology in personal documentation. We introduced our concept of secure hybrid documentation and provided suitable mechanisms to improve their security properties. Part of this work included a fully functional prototype implementation of a robust and reliable key management infrastructure to manage the keys required for access the tag and establish a secure communication channel in RFID-based documents.
In the context of the CIES project, we devised the integration of RFID technology in healthcare environments in order ro improve reliability and safety of involved processes with the provision of two lab-tested solutions. First, we proposed a secure RFID-based medical equipment tracking system for healthcare facilities enabling both real-time locations and theft prevention which lab testing showed up relevant limitations of RFID technology. Moreover, we analyzed and provided a solution for care and control of patients in a hospital. Our prototype provides a secure backup data source from personnel and patients' tags, as well as an offline working mode which increase application reliability and patient's safety.
Security has traditionally been considered once the system is implemented and deployed as an after-the-fact property. This has led to poor security solutions in the form of patches that solve security problems only when a security incident has already caused damage. The area of secure software engineering takes a preventive approach by considering security in every phase of the Software Development Life Cycle (SDLC).
The underlying idea of secure software and service engineering is that software must be built with a security mind-set from the very beginning. Security is a cross-cutting concern that spans along the whole SDLC, from requirements engineering to assurance. Tackling security in every phase in a consistent and holistic way is thus a necessity to build trustworthy services and systems.
We have approached this area by considering both the SDLC as a whole and some of its stages. In the first direction, we have elaborated on development processes and assurance-based development methodologies. In the latter approach, mainly framed within the NESSoS EU project, we are concerned with security requirements specification and security frameworks for assisting during the architecture and implementation phases of the SDLC. In particular, one of our primary focus is on how to include trust and reputation requirements and models as part of systems from the very beginning, and not after-the-fact in an ad-hoc manner, which has been the standard for many years.
Since their origins trust management systems have been used in order to assist entities that have to interact with others in a system. It has been a very important tool for the decision-making process. Sometimes, the information available about the other entities is not enough for establishing a secure exchange of information, but still the interaction must take place. Trust management systems try to supply this lack of information. In the last years, due to the growth of electronic communications and transactions, reputation systems have been developed to aid trust management systems for assisting the trust decision process.
In order to establish the trust relationship a trust management system is usually composed of a symbolic language for representing trust and a way of measuring trust (trust metrics), that derives the trust assessment. At NICS we have mainly concentrated on designing different trust models. In particular, we designed a trust model based on graph theory and characterized the most suitable trust metrics to be used in each case depending on its properties or the nature of the system. Sometimes, the application case is dynamic and therefore the inclusion of time as a parameter for measuring trust is very convenient. We designed a trust model where besides trust and reliability as parameters time was also considered. Other trust models designed at NICS include delegation privileges for access control or a scale-based model. We also investigated how in the context of federated identity management trust perception can be exported by using a federated reputation system.
As an application of trust and reputation management to a specific field we considered the field Wireless Sensor Networks. We identified which are the main features that a trust and reputation management system should include for its application to WSN and which are the best practices that should govern their design. As an extension to the application of trust and reputation management to WSN we have developed a reputation-based early warning system for critical infrastructures.
Wireless Sensor Networks, or WSN, have evolved in the past years from a promising research field to a useful technology applicable to numerous scenarios, such as home and industrial environments. Security is a key factor for the successful deployment of this type of networks, as there are multiple issues (e.g. the capabilities of the nodes and the existence of multiple attack points) that must be carefully considered in order to assure a fault tolerant provisioning of protected services. The importance of security is acknowledged by current WSN specifications, such as Zigbee or ISA100.11a, which define their own security mechanisms and protocols.
Moreover, there are also incoming standards strictly focused on WSN security, such as ISO/IEC 29180 and ITU-IT X.1312. Nevertheless, as security is highly related to the needs of an application and its environment, NICS has been working on the analysis and development of security mechanisms specially adapted for the requirements of WSN applications. Not only NICS has studied different areas such as the use of cryptographic algorithms, the distribution of keying material, and the existence of network status systems, but also has provided some guidelines to integrate those mechanisms in middleware architectures (project SMEPP). Moreover, although WSN is a strategic component of the future Internet of Things, there are still various security challenges that need to be solved from a local perspective. Such challenges were analyzed by NICS in the projects ARES and SPRINT.