A multiplayer game model to detect insiders in wireless sensor networks.

Insiders might have incentives and objectives opposed to those of the belonging organization. It is hard to detect them because of their privileges that partially protect them. In Wireless Sensor Networks (WSNs), significant security issues arise, including compromised nodes by insiders that disrupt the normal network operation. Immediate defensive actions to isolate malicious nodes would mitigate any related impacts. A multiplayer game model is proposed as a solution to the problem of insider attacks in WSNs, the Game of Wireless Sensor Networks (GoWiSeN). It is an imperfect information game, formulated with the use of non-cooperative game theory, holding the assumption that all players are rational. The model consists of several Local Intrusion Detection Systems (LIDSs), which are located to different nodes and communicate with a Global Intrusion Detection System (GIDS). Each LIDS gives suggestions whether the monitoring node is trusted or not. The game is being played between a potential attacker, the nodes and the GIDS. The GIDS is responsible for making a final decision and for isolating a compromised node in case of an internal attack. The theoretical model represents these interactions in an extensive form game. The formal elements of the game are specified, the outcomes of the game are quantified by first specifying players' preferences, and then, by using the von Neumann-Morgenstern utility function, and payoffs are obtained. The game is constructed and solved, by locating NE in pure and mixed strategies. Experimental evaluations conducted on real network datasets, using IDSs of different capabilities, simulate special cases and compromised nodes in a WSN, verify the model efficiency, and show how the game should be played.

Identifying and Analyzing Dependencies in and among Complex Cyber Physical Systems.

Contemporary Critical Infrastructures (CIs), such as the power grid, comprise cyber physical systems that are tightly coupled, to form a complex system of interconnected components with interacting dependencies. Modelling methodologies have been suggested as proper tools to provide better insight into the dependencies and behavioural characteristics of these complex systems. In order to facilitate the study of interconnections in and among critical infrastructures, and to provide a clear view of the interdependencies among their cyber and physical components, this paper proposes a novel method, based on a graphical model called Modified Dependency Structure Matrix (MDSM). The MDSM provides a compact perspective of both inter-dependency and intra-dependency between subsystems of one complex system or two distinct systems. Additionally, we propose four parameters that allow the quantitative assessment of the characteristics of dependencies, including multi-order dependencies in large scale CIs. We illustrate the workings of the proposed method by applying it to a micro-distribution network based on the G2ELAB 14-Bus model. The results provide valuable insight into the dependencies among the network components and substantiate the applicability of the proposed method for analyzing large scale cyber physical systems.

Cyber Risk Propagation and Optimal Selection of Cybersecurity Controls for Complex Cyberphysical Systems.

The increasingly witnessed integration of information technology with operational technology leads to the formation of Cyber-Physical Systems (CPSs) that intertwine physical and cyber components and connect to each other to form systems-of-systems. This interconnection enables the offering of functionality beyond the combined offering of each individual component, but at the same time increases the cyber risk of the overall system, as such risk propagates between and aggregates at component systems. The complexity of the resulting systems-of-systems in many cases leads to difficulty in analyzing cyber risk. Additionally, the selection of cybersecurity controls that will effectively and efficiently treat the cyber risk is commonly performed manually, or at best with limited automated decision support. In this work, we propose a method for analyzing risk propagation and aggregation in complex CPSs utilizing the results of risk assessments of their individual constituents. Additionally, we propose a method employing evolutionary programming for automating the selection of an optimal set of cybersecurity controls out of a list of available controls, that will minimize the residual risk and the cost associated with the implementation of these measures. We illustrate the workings of the proposed methods by applying them to the navigational systems of two variants of the Cyber-Enabled Ship (C-ES), namely the autonomous ship and the remotely controlled ship. The results are sets of cybersecurity controls applied to those components of the overall system that have been identified in previous studies as the most vulnerable ones; such controls minimize the residual risk, while also minimizing the cost of implementation.

A Privacy-Preserving Healthcare Framework Using Hyperledger Fabric.

Electronic health record (EHR) management systems require the adoption of effective technologies when health information is being exchanged. Current management approaches often face risks that may expose medical record storage solutions to common security attack vectors. However, healthcare-oriented blockchain solutions can provide a decentralized, anonymous and secure EHR handling approach. This paper presents PREHEALTH, a privacy-preserving EHR management solution that uses distributed ledger technology and an Identity Mixer (Idemix). The paper describes a proof-of-concept implementation that uses the Hyperledger Fabric's permissioned blockchain framework. The proposed solution is able to store patient records effectively whilst providing anonymity and unlinkability. Experimental performance evaluation results demonstrate the scheme's efficiency and feasibility for real-world scale deployment.

Security, Privacy, and Trustworthiness of Sensor Networks and Internet of Things.

This editorial gives an overview of the papers included in the Special Issue on "Security, Privacy, and Trustworthiness of Sensor Networks and Internet of Things" of Sensors. The context of the special issue theme is first briefly described. This is then followed by an outline of each paper that provides information on the problem addressed; the proposed solution/approach; and, where relevant, the results of the evaluation of the proposed solution.

The challenge for security and privacy services in distributed health settings.

The health care sector is quickly exploiting Information and Communication Technologies towards the provision of e-health services. According to recent surveys, one of the most severe restraining factors for the proliferation of e-health is the (lack of) security measures required to assure both service providers and patients that their relationship and transactions will be carried out in privacy, correctly, and timely. A large number of individuals are not willing to engage in e-health (or are only participating at a reduced level) simply because they do not trust the e-health service providers' sites and the underlying information and communication technologies to be secure enough. This paper considers privacy and security issues and challenges for e-health applications.

High level security policies for health care establishments.

Health Care Establishments (HCE) are today highly dependent upon Information and Communications Technologies (ICT). This increasing reliance upon ICT has stressed the need to foster security in Healthcare Information Systems (HIS). Security policies may have a significant contribution to this effort, but they could become the cause of portability and interoperability problems. Moreover, policies that fail to take into account all the aspects of HIS security, the legal and regulatory requirements, and the existence of several stakeholders may lead to ineffective or inefficient security measures. Policies of a special category, named Generic Security Policies (GSP), should be developed to provide policy-level harmonisation and guidance to policy-makers within HCE. Six such policies are comparatively reviewed herein.

High level security policies for Healthcare Information Systems.

Healthcare Establishments (HCE) have are today highly dependent upon Information and Communications Technologies (ICT). This increasing reliance upon ICT has stressed the need to foster security in Healthcare Information Systems (HIS). Security policies may have a significant contribution to this effort, but they could become the cause of portability and interoperability problems. Moreover, policies that fail to take into account all the aspects of HIS security, the legal and regulatory requirements, and the existence of several stakeholders may lead to ineffective or inefficient security measures. Policies of a special category, named Generic Security Policies (GSPs), should be developed to provide policy-level harmonisation and guidance to policy-makers within HCEs. Five such policies are comparatively reviewed herein.

Quality assured trusted third parties for deploying secure internet-based healthcare applications.

In this paper we present a complete reference framework for the provision of quality assured Trusted Third Party (TTP) services within a medical environment. The main objective is to provide all the basic guidelines towards the development of a quality system for a TTP as an organisation, which could be mapped directly to the requirements of ISO-9000 standards. The important results of the implementation of a quality system, are the enhanced trustworthiness of the TTP and the confidence of the medical society in the provided services. Furthermore, the value added certification services conform to customer requirements and are characterised by efficiency, reliability, security, credibility and trust. The internal organisation acquires a clear and strict structure and maximises its effectiveness by establishing quality management, committed to control, assure and improve quality. The TTP requirements for quality are identified and the various elements of the quality system are described illustratively.

Why we need standardisation in Healthcare security.

This chapter presents the benefits resulting from standardisation in the field of Security in Healthcare Information Systems (HIS). Especially in the EU, standardisation appears as a key element for the effectiveness of the Single Market and the competitiveness of European industry.

Overview on security standards for Healthcare information systems.

The intense need for Healthcare information exchange has revealed a lack of interoperability of systems and applications. Security controls, usually based on proprietary methods and techniques, aggravate the current situation. However, timely development of HIS security standards may improve the interoperability and enable the integration of systems. This chapter provides an overview of the standardisation work that is being done by official standardisation organisations in Europe and world-wide.