The Experts below are selected from a list of 153 Experts worldwide ranked by ideXlab platform
Rodolphe Ortalo - One of the best experts on this subject based on the ideXlab platform.
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a flexible method for information System Security Policy specification
European Symposium on Research in Computer Security, 1998Co-Authors: Rodolphe OrtaloAbstract:This paper presents a method for the specification of the Security of information Systems. The proposed approach provides a flexible and expressive specification method, corresponding to the specific needs of organizations. First, we outline the overall guidelines of the Security Policy definition process, and the different consistency issues associated to the description of the Security requirements of an organization information System. The specification language used is based on a convenient extension of deontic logic. The formalism and its extensions are defined briefly. To illustrate the use of this formalism, the paper presents how the method applies to the description of the Security requirements of a real organization: a medium-size bank agency.
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ESORICS - A Flexible Method for Information System Security Policy Specification
Computer Security — ESORICS 98, 1998Co-Authors: Rodolphe OrtaloAbstract:This paper presents a method for the specification of the Security of information Systems. The proposed approach provides a flexible and expressive specification method, corresponding to the specific needs of organizations. First, we outline the overall guidelines of the Security Policy definition process, and the different consistency issues associated to the description of the Security requirements of an organization information System. The specification language used is based on a convenient extension of deontic logic. The formalism and its extensions are defined briefly. To illustrate the use of this formalism, the paper presents how the method applies to the description of the Security requirements of a real organization: a medium-size bank agency.
Yu Shun-zheng - One of the best experts on this subject based on the ideXlab platform.
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Self-distribution of Network Security Policy Based on Structure-dissimilarity
Computer Science, 2009Co-Authors: Yu Shun-zhengAbstract:The operations of Security Policy's request,update,and execute have put forward higher requirements of the Policy distribution.For purpose of resolving the distribution efficiency of the network Security Policy,the Security Policy self-distribution mathematic model and structural model were proposed based on structure-dissimilarity,which introduced the concepts of distribution factor,Security domain,etc.Expression and making ways of the structure-dissimilarity Policy faced on attribute characters and operation were analyzed emphatically.The Security Policy searching algorithm,comparing algorithm,structure-dissimilarity Policy building algorithm,address assigning and data transmitting algorithm based on Security domain were presented.Compared with the classical entire distribution model,the proposed methods are superior to enhance the System Security Policy disposal efficiency,and occupy the lesser resources of network channel.
Dengguo Feng - One of the best experts on this subject based on the ideXlab platform.
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operating System Security Policy hardening via capability dependency graphs
International Conference on Information Security, 2015Co-Authors: Zhihui Han, Liang Cheng, Yang Zhang, Dengguo FengAbstract:An operating System relies heavily on its access control mechanism to defend against various attacks. The complexities of modern access control mechanisms and the scale of possible configurations are often overwhelming to System administrators and software developers. Therefore, misconfigurations are very common and the Security consequences are serious. It is very necessary to detect and eliminate these misconfigurations. We propose an automated and Systematic approach to address how to correct the misconfigurations based on capability dependency graph generating and MaxSAT solving. Given the attacker’s initial capabilities, we first automatically generate a capability dependency graph to describe attacker’s potential capabilities and the dependency relationships among these capabilities. Based on the capability dependency graph, we then develop a solution to automate the task of hardening operating System Security Policy against multi-step attacks resulting from misconfigurations. In this solution, we first represent each capability obtained by an attacker as a propositional logic formula of initial conditions, and then transfer the Policy hardening problem to a MaxSAT problem. Finally, we present a notation called normal capability loss to aid an administrator to select an optimal hardening solution leading to minimum System usability loss. We apply our approach to analyze misconfigurations in Ubuntu10.04 shipped with SELinux and study an attack case to evaluate the effectiveness of our approach.
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ISPEC - Operating System Security Policy Hardening via Capability Dependency Graphs
Information Security Practice and Experience, 2015Co-Authors: Zhihui Han, Liang Cheng, Yang Zhang, Dengguo FengAbstract:An operating System relies heavily on its access control mechanism to defend against various attacks. The complexities of modern access control mechanisms and the scale of possible configurations are often overwhelming to System administrators and software developers. Therefore, misconfigurations are very common and the Security consequences are serious. It is very necessary to detect and eliminate these misconfigurations. We propose an automated and Systematic approach to address how to correct the misconfigurations based on capability dependency graph generating and MaxSAT solving. Given the attacker’s initial capabilities, we first automatically generate a capability dependency graph to describe attacker’s potential capabilities and the dependency relationships among these capabilities. Based on the capability dependency graph, we then develop a solution to automate the task of hardening operating System Security Policy against multi-step attacks resulting from misconfigurations. In this solution, we first represent each capability obtained by an attacker as a propositional logic formula of initial conditions, and then transfer the Policy hardening problem to a MaxSAT problem. Finally, we present a notation called normal capability loss to aid an administrator to select an optimal hardening solution leading to minimum System usability loss. We apply our approach to analyze misconfigurations in Ubuntu10.04 shipped with SELinux and study an attack case to evaluate the effectiveness of our approach.
Yi Xie - One of the best experts on this subject based on the ideXlab platform.
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implementation and realization of network Security Policy based on rule engine
Journal of Networks, 2011Co-Authors: Chenghua Tang, Yi XieAbstract:In order to solve the implementation and realization efficiency problem of the network information System Security Policy, an improved object-oriented Rete algorithm and its network structure model are proposed, and on this basis, the rule engine is introduced, where the implementation and realization steps and efficiency analysis are given. Result shows that the algorithm and network structure can effectively improve the efficiency of System enforcement and realization. The technology can be adapted to establishing and controlling the Policy service in the extensive network environment.
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An Improved Object-Oriented Rete Algorithm and Network Structure Model
2010 2nd International Symposium on Information Engineering and Electronic Commerce, 2010Co-Authors: Chenghua Tang, Yi XieAbstract:In order to solve the implementation efficiency problem of the network information System Security Policy, an improved object-oriented Rete algorithm and network structure model are proposed. The control methods of the nodes and tokens in the matching algorithm with the pattern join order are studied, that core idea is to use the separate matches to construct matching tree dynamically based on content for achieving significantly reduce the computational results. The improved object-oriented Rete optimize network structure based on the extended Rete class structure is proposed. Result shows that the algorithm and network structure can effectively improve the efficiency of System implementation.
Milos Doroslovacki - One of the best experts on this subject based on the ideXlab platform.
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covert timing channels exploiting non uniform memory access based architectures
Great Lakes Symposium on VLSI, 2017Co-Authors: Fan Yao, Guru Venkataramani, Milos DoroslovackiAbstract:Covert timing channels are a class of information leakage attacks where two processes, namely the trojan and spy, collude with intent to stealthily exfiltrate privileged information even when the underlying System Security Policy prohibits any direct communication between the two processes. In this paper, we present a new type of covert timing channel that exploits the access timing difference between various caches in Non-Uniform Memory Access (NUMA)-based architectures, especially multi-socket CPUs. We demonstrate a realistic covert timing channel implemented on a dual-socket Intel Xeon server. We then explore use of statistical analysis techniques to characterize and quantify the presence of covert timing channel activity. Our experimental results show that such quantification techniques could be a useful first step in formulating an effective defense against NUMA-based covert timing channels.
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ACM Great Lakes Symposium on VLSI - Covert Timing Channels Exploiting Non-Uniform Memory Access based Architectures
Proceedings of the on Great Lakes Symposium on VLSI 2017, 2017Co-Authors: Fan Yao, Venkataramani, Milos DoroslovackiAbstract:Covert timing channels are a class of information leakage attacks where two processes, namely the trojan and spy, collude with intent to stealthily exfiltrate privileged information even when the underlying System Security Policy prohibits any direct communication between the two processes. In this paper, we present a new type of covert timing channel that exploits the access timing difference between various caches in Non-Uniform Memory Access (NUMA)-based architectures, especially multi-socket CPUs. We demonstrate a realistic covert timing channel implemented on a dual-socket Intel Xeon server. We then explore use of statistical analysis techniques to characterize and quantify the presence of covert timing channel activity. Our experimental results show that such quantification techniques could be a useful first step in formulating an effective defense against NUMA-based covert timing channels.
