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Twisted Ate pairing on hyperelliptic curves and applications

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science China({1. sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1.2 1.School of information {1. and technology, sun yat-sen university, guangzhou 51.275, China 2 Guangdong Key Laboratory of information Security technology, guangzhou 51.275, China 1. School of information {1. and technology Sun Yat-Sen University Guangzhou 510275 China2. Guangdong Key Laboratory of Information Security Technology Guangzhou 510275 China

In this paper we show that the twisted Ate pairing on elliptic curves can be generalized to hyperelliptic curves, and give a series of variations of the hyperelliptic Ate and twisted Ate pairings. Using the hyperelliptic Ate pairing and twisted Ate pairing, we propose a new approach to speeding up the Weil pairing computation. For some hyperelliptic curves with high degree twist, computing Weil pairing by our approach may be faster than Tate pairing, Ate pairing, and all other known pairings.

关键词： Ate pairing Weil pairing hyperelliptic curves pairing-based cryptosystems twisted curves

Calibration based universal JPEG steganalysis

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science in China(Series F) 2009年第2期52卷 260-268页

作者： HUANG FangJun1.2 & HUANG JiWu1.2 1.School of information {1. and technology,sun yat-sen university,guangzhou 51.275,China 2 Guangdong Key Lab. of information Security technology,sun yat-sen university,guangzhou 51.275,China School of information {1. and technology Sun Yat-Sen University Guangzhou 510275 China Guangdong Key Lab. of information Security {1. Sun Yat-Sen University Guangzhou 510275 China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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science China({1. sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1.DAI XianHua 2 & Pan DaRu 1.1.School of Physics and Telecommunication Engineering,South China Normal university,{1. 51.006,China 2 department of information science and technology,sun yat-sen university,guangzhou 51.026,China 1. School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to {1.-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

Steganalysis of stochastic modulation steganography

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science in China(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1.2 & HUANG Jiwu1.2 1. School of information {1. and technology, sun yat-sen university, guangzhou 51.275, China 2. Guangdong Province Key Laboratory of information Security, guangzhou 51.275, China 1. School of information {1. and technology Sun Yat-sen University Guangzhou 510275 China 2. Guangdong Province Key Laboratory of information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

A Deniable Authenticated Key Agreement Protocol

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Wuhan university Journal of Natural {1.s 2008年第6期13卷 645-650页

作者： TIAN Haibo1.2, CHEN Xiaofeng1.2, ZHANG Fangguo1.2, WEI Baodian1.2 1. School of information {1. and technology, sun yat-sen university, guangzhou 51.006, Guangdong, China 2. Guangdong Key Laboratory of information Security technology, sun yat-sen university, guangzhou 51.275, Guangdong, China School of information {1. and technology Sun Yat-Sen University Guangzhou 510006 Guangdong China Guangdong Key Laboratory of information Security {1. Sun Yat-Sen University Guangzhou 510275 Guangdong China

This paper presents a deniable authenticated key agreement protocol. This protocol can provide an authenticated session key while the sender and the receiver can deny their involvement in such a protocol if the protocol is executed successfully. Then both can deny their transmitted messages protected by the authenticated session key. If this protocol fails, no authenticated session key can be established and no protected messages can be transmitted. The protocol can be proved secure against key compromise impersonation attack. The protocol employs a new method to isolate a session key from confirmation keys.

关键词： deniable authentication key agreement key compromise impersonation

Robust AVS audio watermarking

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science China({1. sciences) 2010年第3期53卷 607-618页

作者： WANG Yong & HUANG JiWu Guangdong Key Laboratory of information Security {1., School of information science and {1., sun yat-sen university, guangzhou 51.275, China 1. Guangdong Key Laboratory of information Security {1. School of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China

Part Ⅲ of AVS (China Audio and Video Coding Standard) is the first generic audio standard proposed in China and is becoming popular in some applications. For MP3 audio, some effiorts have been made to solve the copyright pirating and malicious modifications by the way of watermarking. To our best knowledge, similar work on the AVS audio has not been explored. In this paper, we present a novel robust watermarking algorithm for AVS audio. We find that the frame type in the AVS coded process can be used as a robust feature for watermarking. Then we design a novel watermarking algorithm which is integrated into the AVS audio coding process. The watermark bits are embedded into the compressed bit stream. At the extracting end, the watermark bits can be extracted from the compressed bit stream directly. This algorithm achieves robustness to decoding/re-coding attacks, and has low computation complexity for both embedding and extracting while preserving the quality of the audio signals.

关键词： AVS audio security problems robust watermarking

Biorthogonal multiple wavelets generated by vector refinement equation

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science China Mathematics 2007年第7期50卷 1015-1025页

作者： Song LI~(1.) Jun XIAN~2 1.department of Mathematics,Zhejiang {1.,Hangzhou 31.027,China 2 department of Mathematics,sun yat-sen university,guangzhou 51.275,China 1. department of Mathematics Zhejiang University Hangzhou 310027 China 2. department of Mathematics Sun Yat-Sen University Guangzhou 510275 China

Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis. In this paper we provide a general method for the construction of compactly supported biorthogonal multiple wavelets by refinable function vectors which are the solutions of vector refinement equations of the form $$\varphi (x) = \sum\limits_{\alpha \in \mathbb{Z}^s } {a(\alpha )\varphi (Mx - \alpha ), x \in \mathbb{R}^s } ,$$ where the vector of functions ? = (? 1. …, ? r)T is in $(L_2 (\mathbb{R}^s ))^r ,a = :(a(\alpha ))_{\alpha \in \mathbb{Z}^s } $ is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim n→∞ M ?n = 0. Our characterizations are in the general setting and the main results of this paper are the real extensions of some known results.

关键词： refinement equation biorthogonal multiple wavelets refinable function vector 42C40 41.1. 41.1. 41.25

Secure multi-party computation protocol for sequencing problem

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science China({1. sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1.2,SHI GuiHua 1.& YAO ZhengAn 3 1.School of Mathematics and information {1.,guangzhou university,guangzhou 51.006, China 2State Key Laboratory of information Security, Institute of Software {1.,Chinese Academy of {1.s,Beijing 1.0080,China 3 School of Mathematics and Computational {1.,sun yat-sen university,guangzhou 51.275,China 1. School of Mathematics and information {1. Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1./2 participants, and an active adversary that can corrupt at most t < n/3 *** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

An Aggregation Composition Compensation Method Based on Paired Net

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International Journal of Automation and computing 2012年第5期9卷 530-538页

作者： Xiao-Yong Mei 1.2 Yi-Yan Fan 2 Chang-Qin Huang 3 Ai-Jun Jiang 1.Shi-Xian Li 1.1.School of information {1. and technology,sun yat-sen university,guangzhou 51.006,China 2 School of Computer {1. and technology,Hunan university of Arts and {1.,Changde 41.000,China 3 department of Electrical Engineering and Computer {1.,university of California,Irvine,CA,92697,USA 1. School of information {1. and technology Sun Yat-sen University Guangzhou 510006 China 2. School of Computer science and {1. Hunan University of Arts and Science Changde 415000 China 3. department of Electrical Engineering and Computer {1. University of California Irvine CA 92697 USA

With regard to the failure and cancellation of business logic of web services composition(WSC),this paper propose a novel web services transaction compensation mechanism based on paired net which can dynamically establish agile compensation-triggered process(CSCP-Nets),and satisfy prospective compensation *** related execution semantics of five usual composition compensation patterns based on paired net are analyzed in the situations of successful execution,failure compensation and failure *** net based application of trip reservation process(TRP) shows that it is feasible.

关键词： Web services composition failure handling composition compensation execution semantic analysis paired net