检索结果-南通市图书馆

A formula on linear complexity of highest coordinate sequences from maximal periodic sequences over Galois rings

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2006年第9期16卷 998-1001页

作者： HU Lei and SUN Nigang (state key laboratory of information security, {5. School of Chinese Academy of Sciences, beijing 100049, china) [a]state key laboratory of information security Graduate School of Chinese Academy of Sciences Beijing China

Using a polynomial expression of the highest coordinate map, we deduce an exact formula on the linear complexity of the highest coordinate sequence derived from a maximal periodic sequence over an arbitrary Galois ring of characteristic p2 , where p is a prime. This generalizes the known result of Udaya and Siddiqi for the case that the Galois ring is Z4.

关键词： Galois ring highest coordinate sequence linear complexity.

Paillier's trapdoor function hides Θ(n) bits

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(information Sciences) 2011年第9期54卷 1827-1836页

作者： SU Dong & Lü KeWei state key laboratory of information security,{5. university of Chinese Academy of Sciences,beijing 100049,china 1. state key laboratory of information security Graduate University of Chinese Academy of Sciences Beijing 100049 China

In this paper,we re-examine the bit security of Paillier’s trapdoor *** show that given a random w=gcyN mod N2 ∈ZN2* the most significant bit of its class c is a hard-core predicate,under a standard assumption that is computing composite residuosity class is *** the simultaneous security,we prove that n number of the class c’s bits are simultaneously hard-core under the standard assumption,where n is the length of c.

关键词： Paillier’s trapdoor function hard-core predicate hard-core function simultaneous security most significant bit

Quantum threshold group signature

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology, beijing university of Technology, beijing 100124, china 2 state {5. laboratory of Integrated Services Network, Xidian university, Xi’an 710071, china 3 state key laboratory of information security (graduate university of Chinese Academy of Sciences), beijing 100049, china 4 state {5. laboratory of Networking and Switching Technology, beijing university of Posts and Tele-communications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China state key laboratory of Integrated Services Network Xidian University Xi’an 710071 China state key laboratory of information security Graduate University of Chinese Academy of Sciences Beijing 100049 China state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

Threshold quantum secret sharing between multi-party and multi-party

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,beijing university of Technology,beijing 100124,china 2 state {5. laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 state key laboratory of information security (graduate university of Chinese Academy of Sciences),beijing 100049,china 4 state {5. laboratory of Networking and Switching Technology,beijing university of Posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing 100124 China state key laboratory of Integrated Services Network Xidian University Xi’an 710071 China state key laboratory of information security ({5. university of Chinese Academy of Sciences) Beijing 100049 China state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Threshold proxy quantum signature scheme with threshold shared verification

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and Technology,beijing university of Technology,beijing 100124,china 2 state {5. laboratory of Networking and Switching Technology,beijing university of Posts and Tele-communications,beijing 100876,china 3 state {5. laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4 state {5. laboratory of information security(graduate university of Chinese Academy of Sciences) ,beijing 100049,china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 China 3. state key laboratory of Integrated Services Network Xidian University Xi’an 710071 China 4. state key laboratory of information security ({5. university of Chinese Academy of Sciences) Beijing 100049 China 2. state key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Multiparty simultaneous quantum identity authentication with secret sharing

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5.1 College of Computer Science and Technology,beijing university of Technology,beijing 100022,china 2 state {5. laboratory of information security (graduate university of the Chinese Academy of Sciences),beijing 100049,china 3 School of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4 Institute of Electronic Technology,information Engineering university,Zhengzhou 45.004,china 5.Trusted Computing laboratory,beijing university of Technology,beijing 100022,china College of Computer Science Technology Beijing University of Technology Beijing 100022 China state key laboratory of information security [graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Threshold quantum secure direct communication without entanglement

在线全文

学校读者我要写书评

暂无评论

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 100022, china 2 School of Science, beijing university of Posts and Telecommunications, beijing 100876, china 3 state key laboratory of information security (graduate School of Chinese Academy of Sciences), beijing 100049, china 1. College of Computer Science and Technology Beijing University of Technology Beijing 100022 China 3. state key laboratory of information security ({5. School of Chinese Academy 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

在线全文

学校读者我要写书评

暂无评论

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 100124, china 2 state {5. 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

SOME RESULTS ON GENERALIZED DIFFERENCE SETS

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2008年第1期21卷 76-84页

作者： Xiwang CAO School of Mathematical Science, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china state key Lab. of information {5., beijing 100049, china. School of Mathematical Science Nanjing University of Aeronautics Astronautics Nanjing 210016 China state key Lab. of information security Beijing 100049 China

Sequences with ideal correlation functions have important applications in communications such as CDMA, FDMA, etc. It has been shown that difference sets can be used to construct such sequences. The author extends Pott and Bradley＇s method to a much broader case by proposing the concept of generalized difference sets. Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations. The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv. Some examples are presented to illustrate that our method works.

关键词： Correlation functions diophantine equations generalized difference sets.