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Twisted Ate pairing on hyperelliptic curves and applications

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Science china(information Sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1,2 1 School of information Science and Technology, sun yat-sen university, guangzhou 510275, china 2 guangdong key laboratory of information security Technology, guangzhou 510275, china 1. School of information Science 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

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 Science and Technology, sun yat-sen university, guangzhou 510275, china 2. guangdong province key laboratory of information security, guangzhou 510275, china 1. School of information Science 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.

Robust AVS audio watermarking

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Science china(information Sciences) 2010年第3期53卷 607-618页

作者： WANG Yong & HUANG JiWu guangdong key laboratory of information security Technology, School of information Science and Technology, sun yat-sen university, guangzhou 510275, china 1. guangdong key laboratory of information security Technology 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

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 Science and Technology,sun yat-sen university,guangzhou 510275,china 2 guangdong key Lab. of information security Technology,sun yat-sen university,guangzhou 510275,china School of information Science and Technology Sun Yat-Sen University Guangzhou 510275 China guangdong key Lab. of information security Technology 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

A Deniable Authenticated key Agreement Protocol

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Wuhan university Journal of Natural Sciences 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 Science and Technology, sun yat-sen university, guangzhou 510006, guangdong, china 2. guangdong key laboratory of information security Technology, sun yat-sen university, guangzhou 510275, guangdong, china School of information Science and Technology Sun Yat-Sen University Guangzhou 510006 Guangdong China guangdong key laboratory of information security Technology 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

RING PROXY SIGNATURES

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Journal of Electronics(china) 2008年第1期25卷 108-114页

作者： Wei Baodian Zhang Fangguo Chen Xiaofeng Department of Electronics and Communication Engineering Sun Yat-Sen University Guangzhou 510275 China Department of Computer Science Sun Yat-Sen University Guangzhou 510275 China guangdong.key laboratory of information security Technology Guangzhou 510275 China

Proxy signatures have been used to enable the transfer of digital signing power within some context and ring signatures can be used to provide the anonymity of a signer. By combining the functionalities of proxy signatures and ring signatures, this paper introduces a new concept, named ring proxy signature, which is a proxy signature generated by an anonymous member from a set of potential signers. The paper also constructs the first concrete ring proxy signature scheme based on the provably secure Schnorr's signatures and two ID-based ring proxy signature schemes. The security analysis is provided as well.

关键词： Proxy signature Ring signature Ring proxy signature ID-based cryptography Bilinear parings

Fabrication and field emission performance of arrays of vacuum microdiodes containing CuO nanowire emitters grown directly on glass without a catalyst

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Science Bulletin 2011年第9期 908-913页

作者： SHAO PengRui, DENG ShaoZhi, CHEN Jun & XU NingSheng* State key laboratory of Optoelectronic Materials and Technologies, guangdong province key laboratory of Display Materials and Technology, School of Physics and Engineering, sun yat-sen university, guangzhou 510275, china

Arrays of vacuum microelectronic sources are fabricated on a glass substrate using cupric oxide (CuO) nanowire emitters. The arrays of electron sources possess a microdiode structure, which can effectively induce field emission and control the delivery of emitted electrons to the anode in a triode-type device operation. A technique for precisely growing CuO nanowires at the centre of microcavities in an array without using a catalyst and at temperatures as low as 400°C is presented. Such a simplified fabrication procedure results in improved field emission performance from the array compared with previous vacuum microelectronic devices. Typical prototype devices have turn-on gate voltages as low as 169 V to give emission current densities of 10 μA/cm2 at the anode. The ratio of anode current to cathode current reaches ~0.85, and the maximum change in emission current density per volt is 1 μA/cm2. Electron emission from the arrays is stable and reproducible under either pulsed or direct current fields. These characteristics indicate that microgate-controlled CuO nanowire emitters may find application in practical devices.

关键词： field emission CuO nanowires vacuum microdiodes arrays emitters

NEW ID-BASED GROUP SIGNATURE FROM PAIRINGS

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Journal of Electronics(china) 2006年第6期23卷 892-900页

作者： Chen Xiaofeng Zhang Fangguo Kwangjo Kim School of information Science and Technology Sun Yat-sen University Guangzhou 510275 China International Research Center for information security Information and Communications University Taejon 305-714 Korea

We argue that traditional identity-based systems from pairings seem unsuitable for designing group signature schemes due to the problem of key escrow. In this paper we first propose new ID-based public key systems without trusted PKG (Private key Generator) from bilinear pairings. In our new ID-based systems, if the dishonest PKG impersonates an honest user to communicate with others, the user can provide a proof of treachery of the PKG afterwards, which is similar to certificate-based systems. Therefore, our systems reach the Girault’s trusted level 3. We then propose a group signature scheme under the new ID-based systems, the security and performance of which rely on the new systems. The size of the group public key and the length of the signature are independent on the numbers of the group.

关键词： Group signature Bilinear pairings Identity-based cryptography

3D-QSAR and Docking Analyses of c-Src Inhibitors

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3D-QSAR and Docking Analyses of c-Src Inhibitors