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Mechanism and Defense on Malicious Code

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Wuhan University Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2.3. QING Si-han 1,2.3.1. Institute of Software, the chinese academy of sciences,{3.,{2. 2.Engineering research center for information security technology, the chinese academy of sciences,{3.,{2. 3.Graduate School of the chinese academy of sciences,{3.,{2. Institute of Software the Chinese Academy of Sciences Beijing 100080 China

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

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 {3. for {2. security technology, Institute of Software, chinese Aca- demy of sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of {2. technology, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 10003., china 1. Engineering research center for {2. {3. technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of information {2. 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.

Identifying heavy hitters in high-speed network monitoring

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Science china(information {2.) 2010年第3期53卷 659-676页

作者： ZHANG Yu1, FANG BinXing1,2.& ZHANG YongZheng2.1research {3. of Computer Network and {2. security technology, Harbin Institute of technology, Harbin 150001, china 2.0} {3. of {2. security, Institute of Computing technology, {12. academy of sciences, beijing 100190, china 1. research center of Computer Network and {2. {3. 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

research on applying physical chaos generator to spacecraft information {2.

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Science china(Technological sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing State Key Laboratory of information security,Graduate University of {2. {3. of sciences,beijing 100049,china china {3. of Space technology,beijing 100094,china State Key Laboratory of information security Graduate University of Chinese Academy of Sciences Beijing 100049 China china academy of Space {2. Beijing 100094 China

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

Recent progress in fingerprint recognition

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Progress in Natural Science:Materials International 2006年第3期16卷 231-240页

作者： TIAN Jie, CHEN Xinjian, ZHANG Yangyang, YANG Xin, HE Yuliang, LI Liang, XIE Weihua and ZHENG Zhipeng (center for Biometrics and security {2., Key Laboratory of Complex Systems and Intelligence Science, Institute of Automation, {3. academy of sciences, beijing 100080, china Graduate School of the chinese academy of sciences, beijing 100080, china) [a]center for Biometrics and security {2. Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Beijing China [b]Graduate School of the chinese academy of sciences Beijing China

Fingerprint recognition has been increasingly used to realize personal identification in civilian' s daily life, such as ID card, fingerprints hard disk and so on. Great improvement has been achieved in the on-line fingerprint sensing technology and automatic fingerprint recognition algorithms. Various fingerprint recognition techniques, including fingerprint acquisition, classification, enhancement and matching, are highly improved. This paper overviews recent advances in fingerprint recognition and summarizes the algorithm proposed for every step with special focuses on the enhancement of low-quality fingerprints and the matching of the distorted fingerprint images. Both issues are believed to be significant and challenging tasks. In addition, we also discuss the common evaluation for the fingerprint recognition algorithm of the Fingerprint Verification Competition 2.04 (FVC2.04) and the Fingerprint Vendor technology Evaluation 2.03.(FpVTE2.03., based on which we could measure the performance of the recognition algorithm objectively and uniformly.

关键词： biometrics fingerprint enhancement matching minutia image registration similarity measures.

Black-box testing based on colorful taint analysis

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Science china(information {2.) 2012年第1期55卷 171-183页

作者： CHEN Kai1,2.3.FENG DengGuo1,SU PuRui1&ZHANG YingJun1,2.3.1State Key Laboratory of information {3.,Institute of Software,{2. academy of Science,beijing 100190,china 2.tate Key Laboratory of information {3.,Graduate University of {2. academy of {13.,beijing 100049,china 3.ational Engineering research center of information {3.,beijing 100190,china 1. State Key Laboratory of information security Institute of Software Chinese Academy of Science Beijing 100190 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China3. National Engineering Research Center of Information Security Beijing 100190 China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3.& WEN QiaoYan2.1 College of Computer Science and technology, beijing University of technology, beijing 10002., china 2.School of Science, beijing University of Posts and Telecommunications, beijing 100876, china 3.State Key Laboratory of information security (Graduate School of {13. academy of {12.), beijing 100049, china 1. College of Computer Science and technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of information security (Graduate School of {2. {3. of sciences) Beijing 100049 China 2. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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Science china(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2.1 College of Computer Science and technology, beijing University of technology, beijing 10012., china 2.State Key Laboratory of information security, Graduate University of chinese academy of sciences, beijing 100049, china College of Computer Science and technology Beijing University of Technology Beijing 100124 China State Key Laboratory of information security Graduate University of Chinese Academy of Sciences Beijing 100049 China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing

Another ID-Based Proxy Signature Scheme and Its Extension

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Wuhan University Journal of Natural sciences 2007年第1期12卷 33-36页

作者： ZHANG Jianhong1,2., ZOU Wei3.1. College of Science, North china University of technology, {2. 100041,china 2. Institute of Software of chinese academy of sciences /State Key Laboratory of information security, beijing 100080, china 3. Institute of Computer Science and technology, Peking University, {2. 100871, china College of Science North China University of Technology Beijing China State Key Laboratory of information security Institute of Software of Chinese Academy of Sciences Beijing China Institute of Computer Science and technology Peking University Beijing China

So fur, the security of many proxy signatures has seldom been considered in a formal way and most of them cannot satisfy nonepudiation. In this work, a novel ID-based （Identity-based） proxy signature scheme is proposed by combining the proxy signature with ID-based public cryptography, and they formalize the notion of security for ID-based proxy signature schemes. And show that the security of the proposed scheme is secure. Compured with other proxy signature schemes, it does not need a secure channel. Thus, it is particularly suitable for the unreliable network computation environment. Finally, they extend proposed scheme to a proxy multi-signature which has the following advantages （1） the size of proxy multi- signature is independent of the number of delegating users; （{3. the computation cost of proxy multi-signature only need two Weil paring.

关键词： proxy signature multisignature security proof