Introduction
The selected cyber-related issue to be investigated is functional safety in physical cyberspace. Gu et al. describe functional safety as a part of the general safety associated with the equipment under control (EUC) and its control system, whose proper functionality depends on safety-related systems (Gu et al. 2020, 1). Functional safety is an aspect that puts the security of cyber-physical systems (CPSs) in the spotlight. CPSs are new systems that integrate computational and physical abilities to allow interaction with humans through new methods (Mo et al. 2014, 8). CPS senses the physical environment and performs feedback operations using computers, communication, and control systems. The aim is to achieve interaction between the physical and cyber worlds. However, this kind of integration poses security and safety challenges due to the vast difference between the two worlds.
Lack of information security and functional safety in the CPS causes confidential information to leak, causing a devastating impact on the physical and cyber worlds (Alam and Saddik 2017, 2050). The problem of function safety exposes the CPS to many security attacks. Functional safety is a cyberspace issue requiring closer examination to identify the security challenges it exposes to CPS. Existing cyber security solutions to address safety and security problems have been unsuccessful. Future research in functional safety will provide a lasting solution to help mitigate the problems posed in cyberspace. Investigating the issue will enable the researcher to explain the best solutions for tackling associated security problems where new methods can be used to defend the CPS from failures and attacks. The paper examines functional safety as a cyber–related issue in cyberspace, clearly stating the problem and explaining why it is an issue, and showing how further research and solution will help mitigate the effects. Solutions to the problem of functional safety will be provided, and an optimal solution will be recommended.
The Problem, its Importance, and the Need for Future Research
Functional safety is a fundamental part of the cyber-space system. It is an issue due to the security problems and associated cyber-attacks it exposes to cyberspace. CPS, cyber security, and functional safety are intertwined, which evolves into a generalized functional safety and security problem (Gu et al. 2020, 1). Ambiguity in applying various technologies, including intelligent, digital, and networking, has led to broken functional safety extensions. System failures and function errors due to random mechanical, physical, and electronic catastrophes break the reliability of functional safety in CPS (Gu et al. 2020, 2). Increased software and central processing unit (CPU) usage have improved conventional functional safety but present cybersecurity issues. That has been evident with unknown cyber-attacks targeting the CPS backdoors and design vulnerabilities, thus subverting operational safety practices and methods (Wu 2019, 371).
Functional safety problem causes fusion effects with cyber security, but the existing solutions to the problem are chaotic to sort out. The problem is uncertain and destructive, where information leakage can cause colossal damage (Gu et al. 2020, 4). Functional safety issue causes superimposed effects of growing problems that outrun human problem-solving capabilities. These effects make the nature of functional safety problems inherent and inevitable. Thus, thoroughly addressing vulnerabilities in cyberspace has been challenging due to the complexity and completeness of human technology development and cognitive level. Institutions and nations have not achieved a self-sustainable technology chain in the globalization era to address the CPS backdoor problem through management engineering (Wu 2022, 156). Furthermore, in complex systems, humans’ scientific and technological abilities do not support scrutiny of software and hardware code vulnerabilities. That remains a technological challenge without a solution even in the foreseeable future.
Functional safety problem in the CPS is an essential issue for examination since previously proposed solutions have not addressed the issue. Cyber security and conventionally dependability technologies have been unable to solve subversive challenges (Gu et al. 2020, 1). They cannot provide security assurance in a quantifiable and verifiable way of responding to cyber-attacks from hardware and software containing harmful security problems. The CPS functional safety facilities and devices have become a scary ghost to the cyber-space. Sliwiski et al. provided a new method that integrates both safety and security industrial control system evaluation using a process and procedure safety and security management. It is a safe-security approach that ensures data integrity and non-rejection only.
Zhou recommended using information security in the industrial Ethernet security protocol stack based on Cortex-A8 (Chun-Jie, Zhou 2013, n.page). The results show that the approach only achieved device authentication, information encryption, and access control measures to solve shared security issues. A cyclic redundancy check only feature detected data integrity errors. The study did not adopt any suitable method of identifying functional safety problems. The study by Ding et al. used an extension approach to quantify the residual error rate for functional safety communication (Ding et al. 2016, 488). The above studies examined solutions to functional safety problems at the risk analysis level and security evaluation. They have not provided a comprehensive analysis or systematic security information on identifying and protecting ideas to solve functional safety problems in cyberspace.
Wu noted that the current cyber security development paradigm does not provide a lasting solution to safety and security problems (Wu 2022, 4). The solution paradigms are based on awareness of the situation and detection analysis. That makes functional safety problem remains stuck as an unsolvable dilemma. Knowing the attacker before and their precise characteristics are not enough ground to base a lasting solution for safety and security problems in cyberspace. According to Jajodia, an ultimate solution to a functional safety problem in cyberspace requires applying a “patch-like” defense mechanism based on threat awareness (Cai et al. 2016, 1123). The move-target defense (MTD) mechanism can reduce attack attempt effectiveness. However, it can still expose the network to security threats since the host execution system and dynamic scheduling step cannot exclude being short-circuited or bypassed by high-risk vulnerabilities.
Dynamism and diversity of the methods cannot achieve changes in the software and hardware vulnerabilities’ logical nature. Preventing internal and external card attacks becomes challenging (Wu 2022, 5). Furthermore, increased transformations of instructions, data, networks, and addresses cause their damage significantly. Further research of the issue and examining the solutions will assist with mitigating the effects of functional safety issues in cyberspace. A holistic method to achieve security goals in cyberspace is needed. Such an approach will recognize the complementary nature of the safety and security outcomes, then highlight problems and possible solutions to the function safety problem of cyber security.
Solutions
Practical solutions to a functional safety problem in cyberspace must address over 51% of common vulnerabilities or backdoor hardware and software problems. The architecture of the proposed methods should guarantee that the common endogenous security problems of the host do not short-circuit the functionality of distributed authentication nodes. A practical solution will have a robust mechanism to counteract disruptions caused by cyber-attacks and the nature of ingestion in cyberspace.
Wu (2022, p.7) proposed the dynamic heterogeneity redundancy (DHR) architecture and coding channel theory (CCT). This approach uses the cyberspace endogenous security paradigm to handle accidental failures and network attacks that are uncertain in an integrated manner. The generalized robust control method of DHR and CCT can solve the entire functional safety problem quantitative design under probability. DHR creates a new way of solving cyberspace’s collective endogenous security problems (Wu 2022, 8). The advantage is that DHR deals with random failures in the structure and guarantees the quantification and verification functionality of the generalized functional safety. However, one disadvantage of the DHR is that the reliability and trustworthiness of this functionality may not be assured when other factors, such as certificate theft, password cracking, and high-risk vulnerabilities to the interaction control, are present. DHR still requires encryption authentication technology support to fight the brutal force attacks at the front door.
Zakoldaev et al. (2020, p.1) proposed using a cluster and matric scheme as the typical structure for cyber and physical production to ensure functional safety in the company. The method engages reserve cyber and physical systems as part of the automatic technological line when the primary equipment elements have failed. CPS specifications help detect failures in time, thus creating equivalent technological lines reliability (Zakoldaev et al. 2020, 4). However, this approach has the disadvantage of depending on the level of functional safety within the smart factory since it may not be applicable at some levels.
The recommended optimal solution for CPS’s functional safety problem is applying functional safety and information security protection methods based on blockchain technology proposed by Gu et al. 2020. In this method, a distributed architecture of CPS is designed on the blockchain structure corresponding to each level. It has helped detect massive defects and risks in the CPS using physical equipment and communication protocols. At each architecture level, the blockchain structure applies a given technology to detect network risks to ensure complete fault diagnosis and protection against risk. Combining the calculation and determination and the encryption method reduces the authentication process complexity.
Conclusion
The functional safety problem is an issue in cyberspace that requires further examination. Ambiguity in applying different technologies to solve the problem has created anxiety around the issue. System failures and function errors make functional safety in CPS unreliable. Increased cyber-attacks at the CPS backdoors and design vulnerabilities have subverted the operational safety practices and efforts to address the problem using various methods. Previous solutions have not effectively addressed security attacks due to the functional safety problem in the CPS. Addressing the issue ultimately requires implementing an approach whose safety and protection mechanisms are applicable at different levels. Blockchain technology provides those capabilities and significantly reduces security risks in the CPS.
References
Alam, Kazi Masudul, and Abdulmotaleb El Saddik. 2017. “C2PS: A Digital Twin Architecture Reference Model for the Cloud-Based Cyber-Physical Systems.” IEEE Access 5, 2050–62. https://doi.org/10.1109/access.2017.2657006.
Cai, Gui-lin, Bao-sheng Wang, Wei Hu, and Tian-zuo Wang. 2016. “Moving Target Defense: State of the Art and Characteristics.” Frontiers of Information Technology & Electronic Engineering 17, no. 11, 1122–53. https://doi.org/10.1631/fitee.1601321.
Chun-Jie, Zhou. 2013. “Development of industrial ethernet security protocol stack based on Cortex-A8.” Computer Engineering and Design.
Ding, Long, Hong Wang, Aidong Xu, and Shixing Li. 2016. “New Considerations for SIL Verification of Functional Safety Fieldbus Communication.” Journal of Loss Prevention in the Process Industries 43, 488–502. https://doi.org/10.1016/j.jlp.2016.07.013.
Gu, Ai, Zhenyu Yin, Chuanyu Cui, and Yue Li. 2020. “Integrated Functional Safety and Security Diagnosis Mechanism of CPS Based on Blockchain.” IEEE Access 8, 15241–15255.
Śliwiński, M., E. Piesik, and J. Piesik. 2018. “Integrated Functional Safety and Cyber Security Analysis.” IFAC-PapersOnLine 51, no. 24, 1263–70. https://doi.org/10.1016/j.ifacol.2018.09.572.
Mo, Haining, Neeti Sharad Wagle, and Michael Zuba. 2014. “Cyber-Physical Systems.” XRDS: Crossroads, The ACM Magazine for Students 20, no. 3, 8–9. https://doi.org/10.1145/2590778.
Wu, Jiangxing. 2019. “The Principle of Cyberspace Mimic Defense.” Wireless Networks, 371–493. https://doi.org/10.1007/978-3-030-29844-9_9.
Wu, Jiangxing. 2022. “Development Paradigms of Cyberspace Endogenous Safety and Security.” Science China Information Sciences 65, no. 5, https://doi.org/10.1007/s11432-021-3379-2.
Wu, JiangXing. 2022. “Problems and Solutions Regarding Generalized Functional Safety in Cyberspace.” Security and Safety 1, 022001. https://doi.org/10.1051/sands/2022001.
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