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Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2,3 & LI Gaicheng1,3 1. engineering research center for information security technology, Institute of Software, chinese academy of sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information technology, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 100039, china 1. engineering research center for information security technology Institute of Software Chinese Academy of Sciences Beijing 100080 China 2. beijing Zhongke Ansheng Corporation of information technology Beijing 100080 China 3. Graduate School of the chinese academy of sciences Beijing 100039 China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Mechanism and Defense on Malicious Code

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Mechanism and Defense on Malicious Code

The 1st chinese Conference on Trusted Computing and information security

作者： WEN Wei-ping, QING Si-nan Institute of Software, the chinese academy of sciences, beijing 100080, china engineering research center for information security technology, the chinese academy of sciences, beijing 100080, china Graduate School of the chinese academy of sciences, beijing 100080, china

＜正＞ With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

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简评欧洲密码大计划的发展现状

计算机科学 2003年第2期30卷 22-25页

作者：张文涛吴文玲卿斯汉中国科学院软件研究所北京100080 中国科学院信息安全技术工程研究中心北京100080

At the 2nd NESSIE workshop on 12-13 September 2001 ,NESSIE gives the selection of 7 primitives from 17 block cipher candidates for further evaluation in Phase Ⅱ. In this paper,the NESSIE evaluation criteria is introduced ,the reason of each candidate for selection or not is explained ,furthermore ,analysis results for each block cipher candidate are listed.

关键词：欧洲密码计划 64比特分组密码密钥密码学

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入侵检测技术研究综述

通信学报 2004年第7期25卷 19-29页

作者：卿斯汉蒋建春马恒太文伟平刘雪飞中国科学院软件研究所北京100080 中国科学院信息安全技术工程研究中心北京100080 中国科学院研究生院北京100080

入侵检测是信息安全保障的关键技术之一。本文综述了入侵检测系统的最新研究进展,包括基本概念、模型、方法等,讨论了该领域尚存在的问题及今后的发展趋势。

关键词：入侵检测误用检测异常检测评估标准化

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一种高效和可扩展的OCSP系统

通信学报 2003年第11期24卷 93-99页

作者：周永彬卿斯汉季庆光张振峰中国科学院软件研究所中国科学院信息安全技术工程研究中心北京100080 信息安全国家重点实验室北京100080

证书状态查询是PKI中的一个关键问题,OCSP是解决这个问题的一种重要机制。本文分析了OCSP协议的技术细节,并在此基础上设计了一种高效的、可扩展的OCSP系统。文中对该系统的关键技术和其自身的安全性问题进行了详细的论述。最后,给出了... 详细信息

证书状态查询是PKI中的一个关键问题,OCSP是解决这个问题的一种重要机制。本文分析了OCSP协议的技术细节,并在此基础上设计了一种高效的、可扩展的OCSP系统。文中对该系统的关键技术和其自身的安全性问题进行了详细的论述。最后,给出了关于OCSP机制的一些未决问题以及某些思考。

关键词：公钥基础设施 OCSP系统证书状态查询认证中心

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NIDS报警信息关联分析进展研究

计算机科学 2004年第12期31卷 61-64页

作者：刘雪飞马恒太张秉权吴伯桥蒋建春文伟平南京理工大学计算机系南京210096 中科院信息安全技术工程研究中心湖南信息技术职业学院计算机系长沙610200

入侵检测技术是当前网络安全领域的一个研究热点,报警关联分析是其中一个重要部分。通过报警信息的关联分析,可以显著地降低入侵检测系统的误警率,提高它的检测率和可用性,帮助网络管理员更好地掌握当前网络的安全状况。本文对当前国际... 详细信息

入侵检测技术是当前网络安全领域的一个研究热点,报警关联分析是其中一个重要部分。通过报警信息的关联分析,可以显著地降低入侵检测系统的误警率,提高它的检测率和可用性,帮助网络管理员更好地掌握当前网络的安全状况。本文对当前国际上报警关联分析技术的研究现状进行了综合分析,并对现有方法进行了分类和比较。

关键词： NIDS 入侵检测技术入侵检测系统网络安全关联分析误警率网络管理员报警信息国际综合分析

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2,3 & LI Gaicheng1,2,3 1. engineering research center for information security technology, Institute of Software, chinese Aca- demy of sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information technology, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 100039, china 1. engineering research center for information security technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of information technology 100080 Beijing China 3. Graduate School of the chinese academy of sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

research of the Gas-solid Flow Character Based on the DEM Method

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Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao research center for Clean Energy and Power,chinese academy of sciences Key Laboratory of Advanced Energy and Power,chinese academy of sciences (Institute of engineering Thermophysics),beijing,100190,china research center for Clean Energy and Power Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

Identifying heavy hitters in high-speed network monitoring

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Science china(information sciences) 2010年第3期53卷 659-676页

作者： ZHANG Yu1, FANG BinXing1,2 & ZHANG YongZheng2 1research center of Computer Network and information security technology, Harbin Institute of technology, Harbin 150001, china 2research center of information security, Institute of Computing technology, chinese academy of sciences, beijing 100190, china 1. research center of Computer Network and information security technology Harbin Institute of Technology Harbin 150001 China2. Research Center of Information Security Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Identifying heavy hitters in a network traffic stream is important for a variety of network applications ranging from traffic engineering to anomaly detection such as detection of denial-of-service attacks. Existing methods generally examine newly arriving items in the stream, perform a small number of operations using a small amount of memory, and still provide guarantees on the identifying accuracy. In high-speed network monitoring, the update speed per item is extremely critical. However, so far as we know, there are no identifying algorithms which can provide constant update time (O(1)) in a weighted data stream. In this paper, we present an algorithm named Weighted Lossy Counting (WLC) which is able to identify heavy hitters in a high-speed weighted data stream with constant update time. WLC employs a novel efficient partially ordered data structure which is able to provide a fast per-item update speed while keeping the memory cost relatively low. We compare WLC with state-of-the-art algorithms for finding heavy hitters in real traffic traces. The experimental results show that WLC performs well in accuracy (recall, precision and average relative error) as other algorithms; moreover it has a much higher update speed at the cost of relatively larger memory space used. A theoretical worst-case memory bound of WLC is also derived in this paper; however, experiments with long real traffic traces show that WLC requires much less space than the theoretical bound in practice.

关键词： network traffic monitoring heavy hitter weighted data streams