Cyber-physical systems security: Limitations,issues and future trends

Typically, Cyber-Physical Systems (CPS) involve various interconnected systems, which can monitor and manipulate real objects and processes. They are closely related to Internet of Things (IoT) systems, except that CPS focuses on the interaction between physical, networking and computation processes. Their integration with IoT led to a new CPS aspect, the Internet of Cyber-Physical Things (IoCPT). The fast and significant evolution of CPS affects various aspects in people’s way of life and enables a wider range of services and applications including e-Health, smart homes, e-Commerce, etc. However, interconnecting the cyber and physical worlds gives rise to new dangerous security challenges. Consequently, CPS security has attracted the attention of both researchers and industries. This paper surveys the main aspects of CPS and the corresponding applications, technologies, and standards. Moreover, CPS security vulnerabilities, threats and attacks are reviewed, while the key issues and challenges are identified. Additionally, the existing security measures are presented and analyzed while identifying their main limitations. Finally, several suggestions and recommendations are proposed benefiting from the lessons learned throughout this comprehensive review.     

Industry 4.0 as a Cyber-Physical System study

Advances in computation and communication are taking shape in the form of the Internet of Things, Machine-to-Machine technology, Industry 4.0, and Cyber-Physical Systems (CPS). The impact on engineering such systems is a new technical systems paradigm based on ensembles of collaborating embedded software systems. To successfully facilitate this paradigm, multiple needs can be identified along three axes: (i) online configuring an ensemble of systems, (ii) achieving a concerted function of collaborating systems, and (iii) providing the enabling infrastructure. This work focuses on the collaborative function dimension and presents a set of concrete examples of CPS challenges. The examples are illustrated based on a pick and place machine that solves a distributed version of the Towers of Hanoi puzzle. The system includes a physical environment, a wireless network, concurrent computing resources, and computational functionality such as, service arbitration, various forms of control, and processing of streaming video. The pick and place machine is of medium-size complexity. It is representative of issues occurring in industrial systems that are coming online. The entire study is provided at a computational model level, with the intent to contribute to the model-based research agenda in terms of design methods and implementation technologies necessary to make the next generation systems a reality.     

信息-物理融合系统若干关键问题综述

信息-物理融合系统(Cyber-Physical System,CPS)集成了计算系统与物理系统,并通过嵌入式计算机与网络实现了两者之间的协作和融合,将对人们的生产和生活方式产生重要影响.CPS是一个全新的研究领域,利用现有基础理论和技术设计CPS时面临着众多问题.介绍了CPS的概念、特点和体系结构,分析了与嵌入式系统、网络的关联,从计算系统、网络系统和控制系统3个方面概括了CPS设计面临的主要挑战,并着重探讨了当前一些可用于CPS设计的理论和技术以及CPS研究的最新进展,指出CPS当前的发展应以解决系统抽象层次设计、系统建模、体系结构设计、数据传输和管理、子系统集成方面的问题作为其下一步发展主要的研究方向,并提出了一些可行的解决办法,可为相关研究提供参考.     

Advanced mobile and wearable systems

The recent spectacular progress in the microelectronic, information, communication, material and sensor technologies created a big stimulus towards development of smart communicating cyber-physical systems (CPS) and Internet of Things (IoT). CPS and IoT are undergoing an explosive growth to a large degree related to advanced mobile systems like smart automotive and avionic systems, mobile robots and wearable devices. The huge and rapidly developing markets of sophisticated mobile cyber-physical systems represent great opportunities, but these opportunities come with a price of unusual system complexity, as well as, stringent and difficult to satisfy requirements of many modern applications. Specifically, smart cars and various wearable systems to a growing degree involve big instant data from multiple complex sensors or other systems, and are required to provide continuous autonomous service in a long time. In consequence, they demand a guaranteed (ultra-)high performance and/or (ultra-)low energy consumption, while requiring a high reliability, safety and security. To adequately address these demands, sophisticated embedded computing and embedded design technologies are needed. After an introduction to modern mobile systems, this paper discusses the huge heterogeneous area of these systems, and considers serious issues and challenges in their design. Subsequently, it discusses the embedded computing and design technologies needed to adequately address the issues and overcome the challenges in order to satisfy the stringent requirements of the modern mobile systems.     

Toward an execution system for self-healing workflows in cyber-physical systems

Cyber-physical systems (CPS) represent a new class of information system that also takes real-world data and effects into account. Software-controlled sensors, actuators and smart objects enable a close coupling of the cyber and physical worlds. Introducing processes into CPS to automate repetitive tasks promises advantages regarding resource utilization and flexibility of control systems for smart spaces. However, process execution systems face new challenges when being adapted for process execution in CPS: the automated processing of sensor events and data, the dynamic invocation of services, the integration of human interaction, and the synchronization of the cyber and physical worlds. Current workflow engines fulfill these requirements only to a certain degree. In this work, we present PROtEUS—an integrated system for process execution in CPS. PROtEUS integrates components for event processing, data routing, dynamic service selection and human interaction on the modeling and execution level. It is the basis for executing self-healing model-based workflows in CPS. We demonstrate the applicability of PROtEUS within two case studies from the Smart Home domain and discuss its feasibility for introducing workflows into cyber-physical systems.     

Integration of decision support systems to improve decision support performance

Decision support system (DSS) is a well-established research and development area. Traditional isolated, stand-alone DSS has been recently facing new challenges. In order to improve the performance of DSS to meet the challenges, research has been actively carried out to develop integrated decision support systems (IDSS). This paper reviews the current research efforts with regard to the development of IDSS. The focus of the paper is on the integration aspect for IDSS through multiple perspectives, and the technologies that support this integration. More than 100 papers and software systems are discussed. Current research efforts and the development status of IDSS are explained, compared and classified. In addition, future trends and challenges in integration are outlined. The paper concludes that by addressing integration, better support will be provided to decision makers, with the expectation of both better decisions and improved decision making processes.     

基于因果逻辑关系的CPS分布式控因研究

针对多子系统间存在复杂因果逻辑关系的信息物理系统(cyber-physical systems,CPS),建立带有未知非线性项和不确定耦合项的CPS多因系统模型,并提出基于云控制技术的分布式控因方法.利用非线性解耦观测器对CPS多因系统进行动态前馈线性化,使得CPS多因系统分解为多个无耦合关联的CPS因系统.设计基于非线性解耦观测器的分布式模型预测控制器以及分布式优化算法,对解耦后的CPS因系统实现在线约束优化控制.最后,通过数值仿真表明所提出控制策略和优化算法的有效性.     

Review on Cyber-physical Systems

Cyber-physical systems (CPS) are complex systems with organic integration and in-depth collaboration of computation, communications and control (3C) technology. Subject to the theory and technology of existing network systems and physical systems, the development of CPS is facing enormous challenges. This paper first introduces the concept and characteristics of CPS and analyzes the present situation of CPS researches. Then the development of CPS is discussed from perspectives of system model, information processing technology and software design. At last it analyzes the main obstacles and key researches in developing CPS.      

Secure SCADA framework for the protection of energy control systems

Energy distribution systems are becoming increasingly widespread in today's society. One of the elements that are used to monitor and control these systems are SCADA (Supervisory Control and Data Acquisition) systems. In particular, these control systems and their complexities, together with the emerging use of the Internet and wireless technologies, bring new challenges that must be carefully considered. Examples of such challenges are the particular benefits of the integration of those new technologies, and also the effects they may have on the overall SCADA security. The main task of this paper is to provide a framework that shows how the integration of different state‐of‐the‐art technologies in an energy control system, such as wireless sensor networks, mobile ad hoc networks, and the Internet, can bring some interesting benefits, such as status management and anomaly prevention, while maintaining the security of the whole system. Copyright © 2010 John Wiley & Sons, Ltd.     

A systems and control perspective of CPS security

The comprehensive integration of instrumentation, communication, and control into physical systems has led to the study of Cyber-Physical Systems (CPSs), a field that has recently garnered increased attention. A key concern that is ubiquitous in CPS is a need to ensure security in the face of cyber attacks. In this paper, we carry out a survey of systems and control methods that have been proposed for the security of CPS. We classify these methods into three categories based on the type of defense proposed against the cyberattacks: prevention, resilience, and detection & isolation. A unified threat assessment metric is proposed in order to evaluate how CPS security is achieved in each of these three cases. Also surveyed are the risk assessment tools and the effect of network topology on CPS security. Furthermore, an emphasis has been placed on power and transportation applications in the overall survey.     

Cyber–physical systems: Extending pervasive sensing from control theory to the Internet of Things

Essentially, the emerging term “Cyber–Physical Systems (CPS)” is an architectural paradigm in which the pervasive sensing technologies represent a fundamental part. Originally defined in the computer sciences domain, the term Cyber–Physical Systems has been adapted to very different domains such as the control theory or electronic engineering. Even, some authors understand CPS as a particular scenario of the Internet of Things (IoT) based on pervasive sensing. Furthermore, recently, some works propose a definition for CPS including all the features described in the different domains. In this paper we provide a comprehensive analysis of the nature and characteristics of the different proposals, discuss the recent attempts to standardize CPS, and review the state-of-the-art on CPS for each technological domain. We compare those different proposals on CPS, discuss about some related terms and technologies and conclude by describing the main research challenges in the area.     

面向服务的信息物理融合系统建模与验证

针对信息物理融合系统(CPS)中建模与验证面临的问题与挑战,基于服务组合的思想,提出一种CPS建模与验证方法。首先,综合分析已有研究成果,提出一种CPS的组成结构,包含物理世界、感知系统、信息处理系统、控制系统及时间约束。基于该结构提出CPS资源的服务分类及组成框架,并利用时间自动机理论,提出CPS物理环境建模方法、CPS原子服务建模方法及服务组合方法。最后,通过案例设计和模型检测工具Uppaal,分别对系统安全性、可达性、活性及时间约束四种类型的性质进行了相关验证。结果表明,系统通过了这些性质的验证,这也证明了面向服务的CPS建模方法的正确性。     

Challenges in business systems integration

Four main frameworks for intercompany relationships (SCOR, CPFR, ISA95 and OAG) are discussed and compared. The link between the frameworks and different supply chain integration applications such as ERP, CRM and VMI are pictured. Finally the state-of-the-art, future state and challenges of the supply chain integration applications are discussed. It is concluded that the main challenge with respect to frameworks supporting business systems integration is to extend them with implementation functionality to better support business system application development. An example of this is customer requirement fulfillment processes such as product development and order fulfillment. Not only do they cross the borders of the company's departments (sales, logistics, purchasing, etc) but also various companies in the supply chain. In spite of this development, business integration across systems and borders are still not matured and to a large extend based on human interaction.     

Integrated moving target defense and control reconfiguration for securing Cyber-Physical systems

With the increasingly connected nature of Cyber-Physical Systems (CPS), new attack vectors are emerging that were previously not considered in the design process. Specifically, autonomous vehicles are one of the most at risk CPS applications, including challenges such as a large amount of legacy software, non-trusted third party applications, and remote communication interfaces. With zero day vulnerabilities constantly being discovered, an attacker can exploit such vulnerabilities to inject malicious code or even leverage existing legitimate code to take over the cyber part of a CPS. Due to the tightly coupled nature of CPS, this can lead to altering physical behavior in an undesirable or devastating manner. Therefore, it is no longer effective to reactively harden systems, but a more proactive approach must be taken. Moving target defense (MTD) techniques such as instruction set randomization (ISR), and address space randomization (ASR) have been shown to be effective against code injection and code reuse attacks. However, these MTD techniques can result in control system crashing which is unacceptable in CPS applications since such crashing may cause catastrophic consequences. Therefore, it is crucial for MTD techniques to be complemented by control reconfiguration to maintain system availability in the event of a cyber-attack. This paper addresses the problem of maintaining system and security properties of a CPS under attack by integrating moving target defense techniques, as well as detection, and recovery mechanisms to ensure safe, reliable, and predictable system operation. Specifically, we consider the problem of detecting code injection as well as code reuse attacks, and reconfiguring fast enough to ensure the safety and stability of autonomous vehicle controllers are maintained. By using MTD such as ISR, and ASR, our approach provides the advantage of preventing attackers from obtaining the reconnaissance knowledge necessary to perform code injection and code reuse attacks, making sure attackers can’t find vulnerabilities in the first place. Our system implementation includes a combination of runtime MTD utilizing AES 256 ISR and fine grained ASR, as well as control management that utilizes attack detection, and reconfiguration capabilities. We evaluate the developed security architecture in an autonomous vehicle case study, utilizing a custom developed hardware-in-the-loop testbed.     

人机智能技术及系统研究进展综述

人机智能系统是能够实现人机智能协作的机器人系统,近年来成为了机器人领域的研究热点,具有广泛的应用前景。针对人机智能系统技术和应用的国内外研究现状,从人机智能系统的关键技术和典型应用领域两方面进行了进展综述。重点综述了与传统机器人系统存在差异性的人机智能系统关键技术,从建模、交互、协同和优化4个方面的研究进展分别展开论述,对涉及的典型应用领域及典型人机智能系统进行总结,并对人机智能系统发展的挑战和未来研究方向进行了展望。     

Cyber-physical systems alter automation architectures

Recent automation systems are well structured according to tasks fulfilled by the functions executed on dedicated devices. These functional assignments are also reasons for the design and topology of fieldbus communication systems. New approaches like Cyber Physical System (CPS) require different approaches according to existing communication technologies and engineering. On one side the interaction models advance, and on the other side the demands for industrial plants become a lot more flexible. This article shows upcoming demands on automation systems and discusses new strategies for software deployment of automation applications and communication systems to fulfill these requirements. This includes handling of different types of functional coupling, e.g. loose coupling with internet/web based technologies for interaction and information management. In addition the current device models offering specific device functions have to be adapted to the new CPS approach.     

Supporting decisions in real-time enterprises: autonomic supply chain systems

Supporting decisions in real time has been the subject of a number of research efforts. This paper reviews the technology and architecture necessary to create an autonomic supply chain for a real-time enterprise for supply chain systems. The technologies weaved together include knowledge-based event managers, intelligent agents, radio frequency identification (RFID), database and system integration, and enterprise resource planning systems. This article is part of the “Handbook on Decision Support Systems” edited by Frada Burstein and Clyde W. Holsapple (2008) Springer.     

离散事件系统框架下信息物理系统攻击问题综述

信息物理系统(cyber physical system, CPS)由受控对象、传感器、执行器、监控器和通信网络组成,通信网络的使用增加了信息物理系统面临外部攻击的风险.鉴于此,综述基于离散事件系统框架处理信息物理系统攻击问题的相关研究工作.首先对信息物理系统进行简要介绍;然后对信息物理系统中的攻击进行分类;最后重点阐述信息物理系统中攻击策略的设计、攻击的检测与防御以及攻击鲁棒性监控器设计的研究现状.     

Data management challenges and development for military information systems

This paper explores challenges facing information system professionals in the management of data and knowledge in the Department of Defense (DOD), particularly in the information systems utilized to support command, control, communications, computers, and intelligence (C/sup 4/ I). These information systems include operational tactical systems, decision-support systems, modeling and simulation systems, and nontactical business systems, all of which affect the design, operation, interoperation, and application of C/sup 4/ I systems. Specific topics include issues in integration and interoperability, joint standards, data access, data aggregation, information system component reuse, and legacy systems. Broad technological trends, as well as the use of specific developing technologies are discussed in light of how they may enable the DOD to meet the present and future information-management challenges.     

信息物理融合系统研究综述

信息物理融合系统(Cyber-physical systems, CPS)是多维异构的计算单元和物理对象在网络环境中高度集成 交互的新型智能复杂系统,具有实时、鲁棒、自治、高效和高性能等特点.本 文首先介绍了CPS的概念和特征,综述了CPS的当前发展状况与应用前景;其次, 对CPS的系统构成进行了简要分析,讨论了CPS与相关技术的区别与联系;最后, 对CPS技术发展所面临的主要挑战及可能的研究方向进行了总结与展望.