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Robust Threshold Guillou-Quisquater Signature Scheme

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 207-210页

作者： WANGHong ZHANGZhen-feng FENGdeng-guo statekeylaboratoryofinformationsecurity（graduateschoolofchineseacademyofsciences） Beijing100039 statekeylaboratoryofinformationsecurity（InstituteofSoftwareofChineseAcademyofSciences） Beijing100080China

The deficiencies of the first threshold Guilbu-Quisquater signature schemepresented by Li-San Liu, Cheng-Kang Chu and Wen-Guey Tzeng arc analysiscd at first, and then a newthreshold Guillou-Quisquater signature scheme is presented. The new scheme isunforgeable and robustagainst any adaptive adversary if the base Guillou-Quisquater signature scheme is unforgeable underthe chosen message attack and computing the discrete logarithm modulo a prime is hard This schemecan also achieve optimal resilience. However, the new scheme does not need the assumption that N isthe product of two safe primes. The basie signature scheme underlying the new scheme is exactlyGuillou-Quisqualtr signature scheme, and the additional strong computation assumption introduced bythe first threshold Guillou-Quisquater scheme is weaken.

关键词： vcriablc secret sharing threshold cryptography digital signature scheme robust secure multiparty computation

SUBGROUPS OF CLASS GROUPS OF ALGEBRAIC QUADRATIC FUNCTION FIELDS

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Chinese Annals of Mathematics,Series B 2003年第3期24卷 315-322页

作者： WANGKUNPENG ZHANGXIANKE statekeylaboratoryofinformationsecurity GraduateSchoolofChineseAcademyofSciencesBeijing100039China DepartmentofMathematicalSciences TsinghuaUniversityBeijing100084China.

Ideal class groups H(K) of algebraic quadratic function fields K are studied. Necessaryand sufficient condition is given for the class group H(K) to contain a cyclic subgroup of anyorder n, which holds true for both real and imaginary fields K. Then several series of functionfields K, including real, inertia imaginary, and ramified imaginary quadratic function fields, aregiven, for which the class groups H(K) are proved to contain cyclic subgroups of order n.

关键词： Function field Quadratic extension Class group Class number Continued fraction

Trace Representations of S-boxes and Their Application

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Wuhan University Journal of Natural Sciences 2004年第2期9卷 173-176页

作者： ZengXiang-yong FuJian-ming LiuHe-guo ZhangHuan-guo SchoolofComputer WuhanUniversityWuhan430072HubeiChina statekeylaboratoryofinformationsecurity(graduateschoolofchineseacademyofsciences) Beijing100039China

In the paper, we use trace representations of Boolean functions to obtain that a class mappings including functionsF(x)=x d over field GF(2 n ), withW(d)=n?1, have desirable cryptographic properties. Therefore we generalize an important result of Nyberg. As application, we use these conclusions to analyze cryptographic property of the S-box of AES (the Advanced Encryption Standard) and give its several equivalent representations, proving that the composition of inversion function of AES and any invertible affine transformations is impossible to satisfy strict avalanche criterion, any order propagation criteria and any order correlation immunity. Key words trace function - nonlinearity - differentially uniform - strict avalanche criterion CLC number TP 309 Foundation item: Supported by the National Natural Science Foundation of China (60373089, 60373041), Natural Science Foundation of Hubei Province (2002AB0037) and Chen-guang Plan of Wuhan City (20025001007).Biography: Zeng Xiang-yong (1973-), male, A postdoctoral fellow, research direction: cryptology and the representation theory of algebra.

关键词： trace function nonlinearity differentially uniform strict avalanche criterion

New Semantic Model for Authentication Protocols in ASMs

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Journal of Computer Science & Technology 2004年第4期19卷 555-563页

作者： RuiXue Deng-GuoFeng statekeylaboratoryofinformationsecurity InstituteofSoftwareTheChineseAcademyofSciencesBeijing100080P.R.China

A new semantic model in Abstract State Model (ASM) for authentication protocols is presented. It highlights the Woo-Lam's ideas for authentication, which is the strongest one in Lowe's definition hierarchy for entity authentication. Apart from the flexible and natural features in forming and analyzing protocols inherited from ASM, the model defines both authentication and secrecy properties explicitly in first order sentences as invariants. The process of proving security properties with respect to an authentication protocol blends the correctness and secrecy properties together to avoid the potential flaws which may happen when treated separately. The security of revised Helsinki protocol is shown as a case study. The new model is different from the previous ones in ASMs.

关键词： cryptographic protocol formal analysis abstract state machine (ASM) authentication protocol

Oblivious Polynomial Evaluation

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Journal of Computer Science & Technology 2004年第4期19卷 550-554页

作者： Hong-DaLi Dong-YaoJi Deng-GuoFeng BaoLi StateKeyLabofInformationSecurity GraduateSchoolofChineseAcademyofSciencesBeijing100039P.R.China

The problem of two-party oblivious polynomial evaluation (OPE) is studied, where one party (Alice) has a polynomial P(x) and the other party (Bob) with an input x wants to learn P(x) in such an oblivious way that Bob obtains P(x) without learning any additional information about P except what is implied by P(x) and Alice does not know Bob's input x. The former OPE protocols are based on an intractability assumption except for OT protocols. In fact, evaluating P(x) is equivalent to computing the product of the coefficient vectors (a(0),...,a(n)) and (1,...,x(n)). Using this idea, an efficient scale product protocol of two vectors is proposed first and then two OPE protocols are presented which do not need any other cryptographic assumption except for OT protocol. Compared with the existing OPE protocol, another characteristic of the proposed protocols is the degree of the polynomial is private. Another OPE protocol works in case of existence of untrusted third party. Keywords oblivious polynomial evaluation, oblivious transfer, secure multi-party computation, information.

关键词： oblivious polynomial evaluation oblivious transfer secure multi-party computation information security

Collision attack on reduced-round Camellia

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Science in China(Series F) 2005年第1期48卷 78-90页

作者： WUWenling FENGDengguo statekeylaboratoryofinformationsecurity InstituteofSoftwareChineseAcademyofSciencesBeijing100080China

Camellia is the final winner of 128-bit block cipher in NESSIE. In this paper, we construct some efficient distinguishers between 4-round Camellia and a random permutation of the blocks space. By using collision-searching techniques, the distinguishers are used to attack on 6, 7, 8 and 9 rounds of Camellia with 128-bit key and 8, 9 and 10 rounds of Camellia with 192/256-bit key. The 128-bit key of 6 rounds Camellia can be recovered with 210 chosen plaintexts and 215 encryptions. The 128-bit key of 7 rounds Camellia can be recovered with 212 chosen plaintexts and 254.5 encryptions. The 128-bit key of 8 rounds Camellia can be recovered with 213 chosen plaintexts and 2112.1 encryptions. The 128-bit key of 9 rounds Camellia can be recovered with 2113.6 chosen plaintexts and 2121 encryptions. The 192/256-bit key of 8 rounds Camellia can be recovered with 213 chosen plaintexts and 2111.1 encryptions. The 192/256-bit key of 9 rounds Camellia can be recovered with 213 chosen plaintexts and 2175.6 encryptions. The 256-bit key of 10 rounds Camellia can be recovered with 214 chosen plaintexts and 2239.9 encryptions.

关键词： block cipher collision attack key data complexity time complexity.

An Additive Problem with Primes in Arithmetic Progressions

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Acta Mathematica Sinica,English Series 2005年第1期21卷 155-168页

作者： ZhenFengZHANG statekeylaboratoryofinformationsecurity InstituteofSoftwareChineseAcademyofSciencesBeijing100080P.R.China

In this paper, we extend a classical result of Hua to arithmetic progressionswith large moduli. The result implies the Linnik Theorem on the least prime in an arithmeticprogression.

关键词： Additive problem Prime Arithmetic progression Circle method

Microbial changes in rhizospheric soils contaminated with petroleum hydrocarbons after bioremediation

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Journal of Environmental Sciences 2004年第6期16卷 987-990页

作者： LINXin LIPei-jun ZHOUQi-xing XUHua-xia ZHANGHai-rong KeyLboratoryofTerrestrialEcologicalProcess InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016China graduateschoolofchineseacademyofsciences Beijing100039China

Effects of bioremediation on microbial communities in soils contaminated with petroleum hydrocarbons are a scientific problem to be solved. Changes in dominate microbial species and the total amount of microorganisms including bacteria and fungi in rhizospheric soils after bioremediation were thus evaluated using field bioremediation experiments. The results showed that there were changed dominant microorganisms including 11 bacterial strains which are mostly Gram positive bacteria and 6 fungal species which were identified. The total amount of microorganisms including bacteria and fungi increased after bioremediation of microbial agents combined with planting maize. On the contrary, fungi in rhizospheric soils were inhibited by adding microbial agents combined with planting soybean.

关键词： bioremediation rhizosphere microbial community contaminated soil petroleum hydrocarbon

Characteristics of nitrogen forms in the southern Huanghai Sea surface sediments

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Acta Oceanologica Sinica 2004年第3期23卷 473-482页

作者： LüXiaoxia SONGJinming LIXuegang YUANHuamao ZHANTianrong LINing GAOXuelu InstituteofOceanology ChineseAcademyofSciencesQingdao266071China graduateschoolofchineseacademyofsciences Beijing100039China

The distributions of different forms of nitrogen in the surface sediments of the southern Huanghai Sea are different and affected by various factors. The contents of IEF-N, SOEF-N and TN gradually decrease eastward, and those of SAEF-N northward, while those of WAEF-N westward. Around the seaport of the old Huanghe (Yellow) River, the contents of both SOEF-N and TN are the highest. Among all the factors, the content of fine sediment is the predominant factor to affect the distributions of different forms of nitrogen. The contents of IEF-N, SOEF-N, and TN have visibly positive correlation with the content of fine sediments, and the correlative coefficient is 0.68, 0.58 and 0.71 respectively, showing that the contents of the three forms of nitrogen increase with those of fine sediments. The content of WAEF-N is related to that of fine sediments to a certain extent, with a correlative coefficient of 0.35; while the content of SAEF-N is not related to that of fine sediments, showing that the content of SAEF-N is not controlled by fine grain-size fractions of sediments. In addition, the distributions of different forms of nitrogen are also interacted one another, and the contents of IEF-N and SOEF-N are obviously affected by TN, while those of inorganic nitrogen (WAEF-N, SAEF-N and IEF-N) are not affected by SOEF-N and TN obviously, although they are interacted each other.

关键词： nitrogen form characteristics controlling factors southern Huanghai Sea surface sediment