Subjective logic provides a means to describe the trust relationship of the real world.However,existing fusion operations it offers treat fused opinions equally,which makes it impossible to deal with the weighted opinions effectively.A.Jφsang presents a solution,which combines the discounting operator and the fusion operator to produce the consensus to the problem.In this paper,we prove that this approach is unsuitable to deal with the weighted opinions because it increases the uncertainty of the consensus.To address the problem,we propose two novel fusion operators that are capable of fusing opinions according to the weight of opinion in a fair way,and one of the strengths of them is improving the trust expressiveness of subjective logic.Furthermore,we present the justification on their definitions with the mapping between the evidence space and the opinion space.Comparisons between existing operators and the ones we proposed show the effectiveness of our new fusion operations.
ZHOU Hongwei1,2,3,SHI Wenchang1,2,LIANG Zhaohui1,2,LIANG Bin1,2 1.Key Laboratory of Data Engineering and Knowledge Engineering,Ministry of Education,Beijing 100872,China
This paper presents a trusted-environment construction method based on the underlying hardware.This method aims at protecting the security-sensitive software in the aspects of software loading,running,and storing in the general operating system.It extends the trust chain of the traditional trusted computing technology to reach the target software,ensuring trusted loading.The extended memory management mechanism effectively prevents memory dumping and memory tampering for the high-sensitivity data.The file monitoring mechanism protects files from vicious operation made by attackers.Flexible-expanded storage environment provides the target software with static storing protection.Experimental system verifies that the method is suitable for general operating system and can effectively protect security-sensitive software with low overhead.
LI Jing1,2,ZHANG Huanguo1,2,ZHAO Bo1,2,FANG Lingling1,2 1.School of Computer,Wuhan University,Wuhan 430072,Hubei,China
Advances in quantum computers threaten to break public key cryptosystems such as RSA, ECC, and EIGamal on the hardness of factoring or taking a discrete logarithm, while no quantum algorithms are found to solve certain mathematical problems on non-commutative algebraic structures until now. In this background, Majid Khan et al.proposed two novel public-key encryption schemes based on large abelian subgroup of general linear group over a residue ring. In this paper we show that the two schemes are not secure. We present that they are vulnerable to a structural attack and that, it only requires polynomial time complexity to retrieve the message from associated public keys respectively. Then we conduct a detailed analysis on attack methods and show corresponding algorithmic description and efficiency analysis respectively. After that, we propose an improvement assisted to enhance Majid Khan's scheme. In addition, we discuss possible lines of future work.
