Browsing by Author "Huang, Chun-Chieh"

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A Flexible Access Control Mechanism for Mobile Commerce
(2011)
Lo, Chi-Chun
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Huang, Chun-Chieh
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Chang, Chung-Huan
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資訊管理與財務金融系註：原資管所+財金所
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Department of Information Management and Finance
In this paper, we propose a flexible access control mechanism, which integrates domain information and confidence values, for mobile commerce. When user requests an access to the data server, the data server fetches and returns results according to the user's access right. Algorithms demonstrate the flexible access control is effective and flexible.
AN EFFICIENT AND SCALABLE EBS-BASED BATCH REKEYING SCHEME FOR SECURE GROUP COMMUNICATIONS
(2009)
Lo, Chi-Chun
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Huang, Chun-Chieh
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Chen, Shu-Wen
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資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
In a multicasting environment, group communications is essential. An important issue of providing secure group communications is group key management. The exclusion basis system (EBS) provides a framework for supporting group key management, especially in a large-size network. In EBS, a key server (KS) is used to generate both administration and session keys. In turn, KS uses these keys to distribute rekeying message to group members so as to keep them from eavesdropping and taping. However, the EBS system does not allow member nodes to join or leave their group. In this paper, we propose an EBS-based batch rekeying scheme which supports three operations, join, leave with collusion-resistant (L/CR), and leave with collusion-free (L/CF). To provide the join operation, KS periodically performs batch rekeying. Karnaugh map (K-map) is used in operation L/CR while the Chinese Remainder Theorem (CRT) is applied to operation L/CF. Both backward and forward secrecies are guaranteed in the proposed scheme. We compare the performance of the proposed scheme with that of EBS in terms of three performance metrics: storage cost, computation overhead, and communication overhead. By comparison, we notice that the proposed scheme outperforms EBS in all three categories. The simulation results also indicate that the proposed scheme is more efficient and scalable than EBS.
Analytical Settling Noise Models of Single-Loop Sigma-Delta ADCs
(2009-10-01)
Chen, Fu-Chuang
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Huang, Chun-Chieh
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電控工程研究所
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Institute of Electrical and Control Engineering
Switched-capacitor integrators are the basic building components for sigma-delta (Sigma Delta) modulators, and their incomplete charge transfer (settling problem) constitutes one of the dominant error sources in Sigma Delta modulators. Due to the complexity of the settling problem, analytic models for related noises are nonexistent. In this brief, closed forms of settling error models are obtained and represented as functions of Sigma Delta modulator system parameters. Both behavioral simulations and transistor-level circuit simulations are employed to verify these analytical models, and the results show that our analytical models are sufficiently accurate.
Front-end amplifier of low-noise and tunable BW/Gain for portable biomedical signal acquisition
(2008)
Huang, Chun-Chieh
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Hung, Shao-Hang
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Chung, Jen-Feng
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Van, Lan-Da
;
Lin, Chin-Teng
We proposed a novel analog circuit design which is suitable for various biomedical signal acquisitions. In addition to the consideration of low power and low noise, the analog front-end integrated Circuit (AFEIC) is presented with design of high common-mode rejection ratio (CMRR) and high power supply ripple rejection ratio (PSRR). It has not only reduced the number of outer components, and enhances a better signal-to-noise ratio (SNR). The chip includes a current-balancing instrumentation amplifier, switched-capacitor filter, non-overlapping clock generator, and a programmable gain amplifier (PGA). It was fabricated by TSMC 0.35 mu m CMOS 2P4M standard process, with CMRR 155 dB CMRR, 131 dB of PSRR+, and 127 dB of PSRR- at 50 Hz. The power consumption is about 142.4 mu W under +/- 1.5V supply.
Threshold Based Group-Oriented Nominative Proxy Signature Scheme for Digital Rights Management
(2010)
Huang, Chun-Chieh
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Lo, Chi-Chun
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資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
Digital Rights Management (DRM) is a system to protect high-value digital assets and control the distribution and usage of those digital assets. Digital licensing controls the contents to be accessed by the consumers. One of the major issues raised by DRM systems concerns the integrity of this license. In this paper, we propose a threshold based group-oriented nominative proxy signature scheme (TB-GO-NPSS) which supports an original provider to delegate his/her signing ability to the partial members of the proxy group having n members and to designate the partial members of the verifier group having 1 members to verify his/her digital licenses for the mobile users. The proposed scheme can guarantee that the digital products come from the authorized providers. A formal security analysis demonstrates that our scheme is secure enough to be used in DRM systems.