Biblio
In this paper we consider the threat surface and security of air gapped wallet schemes for permissioned blockchains as preparation for a Markov based mathematical model, and quantify the risk associated with private key leakage. We identify existing threats to the wallet scheme and existing work done to both attack and secure the scheme. We provide an overview the proposed model and outline justification for our methods. We follow with next steps in our remaining work and the overarching goals and motivation for our methods.
Cyber-Physical Systems (CPS) is mostly deployed in security-critical applications where their failures can cause serious consequences, and therefore it is critical to evaluate its availability. In this paper, an architecture model of CPS is established from the perspective of object-oriented system. The system is a unified whole formed by various independent objects (including sensors, controllers and actuators) through communication connection. Then the paper presents the Object-oriented Timed Petri Net to model the system. The modeling method can be used to describe the whole system and the characteristics of the object. At the same time, the availability analysis of the system is carried out by using the mathematical analysis method and simulation tool of Petri net. Finally, a concrete case is given to verify the feasibility of the modeling method in CPS availability analysis.
Usually, the air gap will appear inside the composite insulators and it will lead to serious accident. In order to detect these internal defects in composite insulators operated in the transmission lines, a new non-destructive technique has been proposed. In the study, the mathematical analysis model of the composite insulators inner defects, which is about heat diffusion, has been build. The model helps to analyze the propagation process of heat loss and judge the structure and defects under the surface. Compared with traditional detection methods and other non-destructive techniques, the technique mentioned above has many advantages. In the study, air defects of composite insulators have been made artificially. Firstly, the artificially fabricated samples are tested by flash thermography, and this method shows a good performance to figure out the structure or defects under the surface. Compared the effect of different excitation between flash and hair drier, the artificially samples have a better performance after heating by flash. So the flash excitation is better. After testing by different pollution on the surface, it can be concluded that different pollution don't have much influence on figuring out the structure or defect under the surface, only have some influence on heat diffusion. Then the defective composite insulators from work site are detected and the image of defect is clear. This new active thermography system can be detected quickly, efficiently and accurately, ignoring the influence of different pollution and other environmental restrictions. So it will have a broad prospect of figuring out the defeats and structure in composite insulators even other styles of insulators.
This paper presents an efficiency and adaptive cryptographic protocol to ensure users' privacy and data integrity in RFID system. Radio Frequency Identification technology offers more intelligent systems and applications, but privacy and security issues have to be addressed before and after its adoption. The design of the proposed model is based on clustering configuration of the involved tags where they interchange the data with the reader whenever it sends a request. This scheme provides a strong mutual authentication framework that suits for real heterogeneous RFID applications such as in supply-chain management systems, healthcare monitoring and industrial environment. In addition, we contribute with a mathematical analysis to the delay analysis and optimization in a clustering topology tag-based. Finally, a formal security and proof analysis is demonstrated to prove the effectiveness of the proposed protocol and that achieves security and privacy.
Cloud computing is an emerging paradigm shifting the shape of computing models from being a technology to a utility. However, security, privacy and trust are amongst the issues that can subvert the benefits and hence wide deployment of cloud computing. With the introduction of omnipresent mobile-based clients, the ubiquity of the model increases, suggesting a still higher integration in life. Nonetheless, the security issues rise to a higher degree as well. The constrained input methods for credentials and the vulnerable wireless communication links are among factors giving rise to serious security issues. To strengthen the access control of cloud resources, organizations now commonly acquire Identity Management Systems (IdM). This paper presents that the most popular IdM, namely OAuth, working in scope of Mobile Cloud Computing has many weaknesses in authorization architecture. In particular, authors find two major issues in current IdM. First, if the IdM System is compromised through malicious code, it allows a hacker to get authorization of all the protected resources hosted on a cloud. Second, all the communication links among client, cloud and IdM carries complete authorization token, that can allow hacker, through traffic interception at any communication link, an illegitimate access of protected resources. We also suggest a solution to the reported problems, and justify our arguments with experimentation and mathematical modeling.