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Second-Order Power Analysis Attacks against Precomputation based Masking Countermeasure
Weijian Li,Haibo Yi 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.3
Precomputation look-up table based masking countermeasure is low-cost and secure against first-order DPA, therefore is more suitable for lightweight ciphers in resourceconstrained devices. In this paper, we investigate the resistance of this masking countermeasure against second-order power analysis attack under the attack context of the Hamming weight leakage and the precomputation masked S-box. We improve the Adapted CPA technique [1] to make a better use of this attack context. Our attack successfully reveals the secret key with and without electronic noise and algorithmic noise. The number of power traces required to reveal the secret key rises from 600(unprotected implementation) to 16,000.
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Haibo Yi,Weijian Li,Zhe Nie 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.9
Inversions in small finite fields are the most computationally intensive field arithmetic and have been playing a key role in areas of cryptography and engineering. The main algorithms for small finite field inversions are based on Fermat's little theorem, extended Euclidean algorithm, Itoh-Tsujii algorithm and other methods. In this brief, we present techniques to exploit special irreducible polynomials for fast inversions in small finite fields GF(2n) , where n is a positive integer and 0 < n < 16 . Then, we propose fast inversions based on Fermat's theorem for two special irreducible polynomials in small finite fields, i.e. trinomials and All-One-Polynomials (AOPs). Trinomials can be represented by polynomials xn + xm + 1 and AOPs can be represented by polynomials xn + Xn-1 + ... +1 , where m is a positive integer and 0 < m < n . Our designs have low hardware requirements, regular structures and are therefore suitable for hardware implementation. After that, our designs are programmed in Very-High-Speed Integrated Circuit Hardware Description Language (VHDL) by using integrated environment Altera Quartus II and implemented on a low-cost Field- Programmable Gate Array (FPGA). The experimental results on FPGAs show that our designs provide significant reductions in executing time of inversions in small finite fields, e.g. the executing time of inversion in GF(27) is 18.80 ns and the executing time of inversion in GF(212) is 29.57 ns.
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Fast Three-Input Multipliers over Small Composite Fields for Multivariate Public Key Cryptography
Haibo Yi,Weijian Li 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.9
Since quantum computer attacks will be threats to the current public key cryptographic systems, there has been a growing interest in Multivariate Public Key Cryptography (MPKC), which has the potential to resist such attacks. Finite field multiplication is playing a crucial role in the implementations of multivariate cryptography and most of them use two-input multipliers. However, there exist multiple multiplications of three elements in multivariate cryptography. This motivates our work of designing three-input multipliers, which extend the improvements on multiplication of three elements in three directions. First, since multivariate cryptography can be implemented over small composite fields, our multipliers are designed over such fields. Second, since it requires multiplications of two and three elements, our multipliers can execute both of them. Third, our multipliers adapt table look-up and polynomial basis, since they are faster over specific fields, respectively. We demonstrate the improvement of our design mathematically. We implement our design on a Field-Programmable Gate Array (FPGA), which shows that our design is faster than other two-input multipliers when computing multiplication of three elements, e.g. multiplier with field size 256 is 28.4% faster. Our multipliers can accelerate multivariate cryptography and mathematical applications, e.g. TTS is 14% faster.
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Seismic analysis of CFST frames considering the effect of the floor slab
Huang Yuan,Yi Weijian,Nie Jianguo 국제구조공학회 2012 Steel and Composite Structures, An International J Vol.13 No.4
This paper describes the refined 3-D finite element (FE) modeling of composite frames composed of concrete-filled steel tubular (CFST) columns and steel-concrete composite beams based on the test to get a better understanding of the seismic behavior of the steel-concrete composite frames. A number of material nonlinearities and contact nonlinearities, as well as geometry nonlinearities, were taken into account. The elastoplastic behavior, as well as fracture and post-fracture behavior, of the FE models were in good agreement with those of the specimens. Besides, the beam and panel zone deformation of the analysis models fitted well with the corresponding deformation of the specimens. Parametric studies were conducted based on the refined finite elememt (FE) model. The analyzed parameters include slab width, slab thickness, shear connection degree and axial force ratio. The influences of these parameters, together with the presence of transverse beam, on the seismic behavior of the composite frame were studied. And some advices for the corresponding seismic design provisions of composite structures were proposed.
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Behavior and Design of Distributed Belt Walls as Virtual Outriggers for Concrete High-Rise Buildings
Tae-Sung Eom,Hiubalt Murmu,Weijian Yi 한국콘크리트학회 2019 International Journal of Concrete Structures and M Vol.13 No.2
A new lateral force-resisting structural system for concrete high-rise buildings, distributed belt wall system, is proposed. Unlike conventional belt structures, the belt walls infilling the space between perimeter columns are distributed separately along the overall building height. In this study, the force transfer mechanism and performance of the distributed belt walls, acting as virtual outriggers under lateral load, are investigated. For the reinforcement of the belt walls subjected to high shear demand, a reinforcing method using high-strength prestressing strands (i.e. PSC belt wall) is suggested, and the shear strength of the PSC belt walls is estimated based on the compression field theory. By performing nonlinear finite element analysis, the shear behavior of the PSC belt walls, including cracking and yield strengths, is investigated in detail. Based on these investigations, recommendations for the shear design of the belt walls reinforced by high-strength prestressing strands are given.
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