Biblio
Cyber security risk assessment is very important to quantify the security level of communication-based train control (CBTC) systems. In this paper, a methodology is proposed to assess the cyber security risk of CBTC systems that integrates complex network theory and attack graph method. On one hand, in order to determine the impact of malicious attacks on train control, we analyze the connectivity of movement authority (MA) paths based on the working state of nodes, the connectivity of edges. On the other hand, attack graph is introduced to quantify the probabilities of potential attacks that combine multiple vulnerabilities in the cyber world of CBTC. Experiments show that our methodology can assess the security risks of CBTC systems and improve the security level after implementing reinforcement schemes.
This paper argues that the security management of the robot supply chain would preferably focus on Sino-US relations and technical bottlenecks based on a comprehensive security analysis through open-source intelligence and data mining of associated discourses. Through the lens of the newsboy model and game theory, this study reconstructs the risk appraisal model of the robot supply chain and rebalances the process of the Sino-US competition game, leading to the prediction of China's strategic movements under the supply risks. Ultimately, this paper offers a threefold suggestion: increasing the overall revenue through cost control and scaled expansion, resilience enhancement and risk prevention, and outreach of a third party's cooperation for confrontation capabilities reinforcement.
Secure multi-party computation(SMPC) is an important research field in cryptography, secure multi-party computation has a wide range of applications in practice. Accordingly, information security issues have arisen. Aiming at security issues in Secure multi-party computation, we consider that semi-honest participants have malicious operations such as collusion in the process of information interaction, gaining an information advantage over honest parties through collusion which leads to deviations in the security of the protocol. To solve this problem, we combine information entropy to propose an n-round information exchange protocol, in which each participant broadcasts a relevant information value in each round without revealing additional information. Through the change of the uncertainty of the correct result value in each round of interactive information, each participant cannot determine the correct result value before the end of the protocol. Security analysis shows that our protocol guarantees the security of the output obtained by the participants after the completion of the protocol.