掲載種別：研究論文（国際会議プロシーディングス）  

RSA-like cryptosystems, based on the original RSA algorithm, are gaining attention as potential alternatives to traditional techniques. They offer better security, efficiency, flexibility, and compatibility in cryptography. However, recent studies have uncovered vulnerabilities in these variants, particularly to Wiener-type attacks, despite initial expectations of security comparable to RSA. In this paper, we further investigate the security vulnerabilities of a variant of this technique, namely the Murru-Saettone (MS) cryptosystem. Our investigation employs lattice-based attacks to exploit weaknesses in systems with small private keys. It demonstrates that if the private exponent is smaller than N1/4, where N is the product of two distinct balanced primes, the small exponent of the cryptosystem can be recovered.

DOI： 10.1109/ICCE-Taiwan62264.2024.10674633

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掲載種別：研究論文（国際会議プロシーディングス）  

CP-ABE emerges as an advanced cryptographic method that offers secure and precise access control in Internet of Things and cloud storage applications. Nevertheless, the original CP-ABE algorithm relied on the PBC library with a security level limited to 80 bits and is now outdated, making it vulnerable to attacks. To address this issue, we have introduced ELiPS-based CP-ABE, which boosts the level of security to 128 bits using the ELiPS library. While this enhancement improved the overall performance, the decryption functions remained computationally intensive. To tackle this, we previously optimized the decryption function by minimizing final exponentiations and inversions. In this paper, we evaluate and analyze the impact of these optimizations on decryption efficiency. Moreover, we compare the ELiPS-based CP-ABE with these improvements to the initial version and the original PBC-based CP-ABE. As a result, the combination of both optimization techniques resulted in an average 43.06% overall reduction in decryption time compared to the initial version of the ELiPS-based CP-ABE scheme, while in total execution, it led to a 25.27% improvement. Furthermore, there was an average 53.81% overall reduction in total execution time compared to the original PBC-based CP-ABE method.

DOI： 10.1007/978-981-97-5810-4_30

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掲載種別：研究論文（国際会議プロシーディングス）  

CKKS homomorphic encryption is frequently utilized in cloud-based applications due to its ability to handle both real and complex numbers, ensuring the protection of sensitive data. However, the security of CKKS encryption relies on an encoding process to convert input data into a polynomial. While this process involves the Inverse Fast Fourier Transform (IFFT), there are two notable issues with IFFT: first, most multiplications between complex numbers require four multiplications between real numbers, and second, there are delays in processing due to data hazards. In this paper, we propose an effective way to handle these issues by substituting them using parallelization based on the sum of complex conjugates. This approach aims to reduce the multiplication cost, thereby improving processing time compared to IFFT.

DOI： 10.1109/ICCE-Taiwan62264.2024.10674426

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掲載種別：研究論文（国際会議プロシーディングス）  

The proliferation of the Internet of Things leads to the sharing of more data among diverse stakeholders, ranging from individual users to large enterprises. However, ensuring the security of this data exchange while simultaneously minimizing errors during transmission presents a complex challenge. Due to the involvement of numerous devices and users capable of data sharing, the dynamic and heterogeneous nature of the environment leads to constant changes. In this paper, we integrate the Kyber algorithm for post-quantum security with Bose-Chaudhuri-Hocquenghem (BCH) codes for error correction. We validate our approach by transmitting images from the widely- used CIFAR-10 dataset in encrypted mode over noisy communication channels. The system demonstrates effective image encryption and robust error correction capabilities.

DOI： 10.1109/ICCE-Taiwan62264.2024.10674282

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掲載種別：研究論文（国際会議プロシーディングス）  

Post-Quantum Cryptography (PQC) is becoming popular since it offers protection against quantum attacks. CRYSTALS-Dilithium is being considered as a promising NIST PQC standard candidate. It utilizes the Radix-2 Number Theoretic Transform (NTT). Its reliance on lattice-based cryptography and number-theoretic principles positions CRYSTALS-Dilithium as a strong contender for providing robust security in the era of quantum computing. Besides, the Radix-4 NTT divides polynomials into more parts than the Radix-2 NTT, making calculations more efficient by reusing values. In this paper, we improve the computational efficiency of CRYSTALS-Dilithium by implementing the Radix-4 NTT algorithm in both C and Rust programming languages. We verified the effectiveness through experiments in terms of signature and verification speeds. Additionally, we analyzed the assembly code generated by both languages to understand the performance differences.

DOI： 10.1109/ICCE-Taiwan62264.2024.10674226

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掲載種別：研究論文（国際会議プロシーディングス）  

Global healthcare systems face growing pressure as populations rise. This can lead to longer wait times and an increased risk of treatment delays or misdiagnosis. Artificial intelligence (AI) diagnostic systems are being developed to address these challenges, but concerns exist about their accuracy and data security. This study introduces a robust AI telehealth system that offers a two-pronged approach. It utilizes a cutting-edge image analysis method, vision transformer, to enhance diagnostic accuracy, while also incorporating post-quantum cryptography algorithm, Kyber, to ensure patient privacy. Furthermore, an interactive visualization tool aids in interpreting the diagnostic results, providing valuable insights into the model's decisionmaking process. This translates to faster diagnoses and potentially shorter wait times for patients. Extensive testing with various datasets has demonstrated the system's effectiveness. The optimized model achieves a remarkable 95.79% accuracy rate in diagnosing COVID-19 from chest X-rays, with the entire process completed in under five seconds.

DOI： 10.1109/MWSCAS60917.2024.10658795

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掲載種別：研究論文（国際会議プロシーディングス）  

In the digital age, organizations commonly use photos to share their activities for brand visibility. However, it is crucial to safeguard the facial information of individuals depicted in these photos to prevent potential misuse. In this paper, we propose a single-party security system for enabling selective image privacy with a focus on facial regions, called SnapSafe. It adopts the YOLOv8 deep learning model for face detection, AES encryption for security, and QR technology to store the encrypted face region coordinates. Our evaluation assesses the effectiveness of the system through the usability of its face locking and unlocking processes, alongside an analysis of its running time. The results demonstrate the system's proficiency in executing face protection tasks with high accuracy and minimal time overhead, thus indicating its suitability for real-time applications.

DOI： 10.1109/ITC-CSCC62988.2024.10628222

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掲載種別：研究論文（国際会議プロシーディングス）  

Pollard's rho method is a widely used probabilistic algorithm for solving the Elliptic Curve Discrete Logarithm Problem (ECDLP). To enhance its efficiency, the skew Frobenius mapping (SFM) has been incorporated into the method, reducing the average number of steps required to find a collision. However, the combination of Pollard's rho method with SFM introduces the occurrence of fruitless cycles, which are computational loops that do not contribute to solving the ECDLP and hinder the overall attacking efficiency. This paper presents a comprehensive analysis of fruitless cycles in Pollard's rho method with SFM, focusing on their impact when applied to Barreto-Naehrig (BN) curves. We propose a scheme to mitigate the occurrence of fruitless cycles by optimizing the seed point selection to be adaptive according to situation. To validate the effectiveness of our proposed method, we perform comprehensive experiments and compare the results with the conventional Pollard's rho method with SFM. The results indicate that the proposed approach significantly reduces the occurrence of fruitless cycles, leading to faster and more efficient ECDLP attacks on BN curves.

DOI： 10.1109/ITC-CSCC62988.2024.10628268

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掲載種別：研究論文（国際会議プロシーディングス）  

Utilizing Machine Learning (ML) techniques to construct models for Intrusion Detection Systems (IDS) has emerged as a leading strategy to enhance security measures. Previously, we applied an ensemble of Support Vector Machines (SVM) for model training, achieving an accuracy detection rate of 88.6% on familiar datasets. However, it performs poorly on unknown datasets due to overfitting problems. This work aims to improve accuracy and tackle overfitting problems by implementing stacked Long Short-Term Memory (LSTM) networks. Furthermore, analysis of variance (ANOVA) with F-test is used to find the important feature. The synthetic minority oversampling technique (SMOTE) algorithm is applied to obtain balanced data. Several experiments were conducted to analyze the performance of the proposed approach, including investigating stacked LSTM with tuning hyperparameters. The proposed method achieved the highest prediction accuracy of 97.23% and an overfitting value of 0.24%.

DOI： 10.1109/ICCE59016.2024.10444231

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掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/ijnc/ijnc14.html#HossainRAHKN24

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE59016.2024.10444231

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その他リンク： https://dblp.uni-trier.de/db/conf/iccel/icce2024.html#MusthafaHAKN24

掲載種別：研究論文（学術雑誌）  

Global food security is a pressing issue that affects the stability and well-being of communities worldwide. While existing Internet of Things (IoT) enabled plant monitoring systems have made significant strides in agricultural monitoring, they often face limitations such as high power consumption, restricted mobility, complex deployment requirements, and inadequate security measures for data access. This paper introduces an enhanced IoT application for agricultural monitoring systems that address these critical shortcomings. Our system strategically combines power efficiency, portability, and secure access capabilities, assisting farmers in monitoring and tracking crop environmental conditions. The proposed system includes a remote camera that captures images of surrounding plants and a sensor module that regularly monitors various environmental factors, including temperature, humidity, and soil moisture. We implement power management strategies to minimize energy consumption compared to existing solutions. Unlike conventional systems, our implementation utilizes the Amazon Web Services (AWS) cloud platform for reliable data storage and processing while incorporating comprehensive security measures, including Two-Factor Authentication (2FA) and JSON Web Tokens (JWT), features often overlooked in current agricultural IoT solutions. Users can access this secure monitoring system via a developed Android application, providing convenient mobile access to the gathered plant data. We validate our system’s advantages by implementing it with two potted garlic plants on Okayama University’s rooftop. Our evaluation demonstrates high sensor reliability, with strong correlations between sensor readings and reference data, achieving determination coefficients (R2) of 0.979 for temperature and 0.750 for humidity measurements. The implemented power management strategies extend battery life to 10 days on a single charge, significantly outperforming existing systems that typically require daily recharging. Furthermore, our dual-layer security implementation utilizing 2FA and JWT successfully protects sensitive agricultural data from unauthorized access.

DOI： 10.32604/cmc.2024.058144

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/candarw60564.2023.00044

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-Taiwan58799.2023.10226697

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2023.html#MusthafaAHKKN23

記述言語：英語   出版者・発行元：IJNC Editorial Committee  

Pairing is carried out by two steps, Miller loop and final exponentiation. In this manuscript, the authors propose an efficient Miller loop for a pairing on the FK12 curve. A Hamming weight and bit-length of loop parameter have a great effect on the computational cost of the Miller loop. Optimal-ate pairing is used as the most efficient pairing on the FK12 curve currently. The loop parameter of optimal-ate pairing is 6z + 2 where z is the integer to make the FK12 curve parameter. Our method uses z which has a shorter bit-length than the previous optimal-ate pairing as the loop parameter. Usually, z has a low Hamming weight to make final exponentiation efficient. Therefore, the loop parameter in our method has a lower Hamming weight than the loop parameter of the previous one in many cases. The authors evaluate our method by the number of multiplications and execution time. As a result, the proposed algorithm leads to a 3.71% reduction in the number of multiplications and a 3.03% reduction in the execution time. In addition, the authors implement other STNFS secure curves and evaluate these curves from viewpoint of execution time.

DOI： 10.15803/ijnc.13.2_242

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-Taiwan58799.2023.10226716

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2023.html#MiyoshiIAKKN23

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その他リンク： https://dblp.uni-trier.de/db/journals/ijnc/ijnc13.html#IkesakaNKKN23

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/SmartNets58706.2023.10215620

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その他リンク： https://dblp.uni-trier.de/db/conf/smartnets/smartnets2023.html#HudaNARHMAJ23

掲載種別：研究論文（国際会議プロシーディングス）  

In today's interconnected digital era, email stands as a primary platform for communication across various fields, such as business, academia, and personal interactions. Since it operates on shared mediums, email is inherently susceptible to interception and misuse of sensitive information. To cover this issue, Pretty Good Privacy (PGP) ensures the confidentiality of email contents. However, while PGP effectively encrypts the body of messages, a significant vulnerability emerges during key sharing. Blockchain technology comes with its immutability aspect. Once data is embedded into the blockchain, modifying it becomes exceedingly challenging. This makes it a potential safeguard against the vulnerabilities in PGP's key sharing mechanism. Additionally, smart contracts remove the requirement of a Man-in-the-Middle for sharing key, which enhances the sharing key's security and builds trust among users. In this paper, we integrate the strengths of blockchain into the PGP encryption process, specifically targeting the key sharing vulnerability. Also, we adopt Elliptic Curve Cryptography (ECC) to ensure the confidentiality of the PGP's key. First, generate the PGP's key. Then, encrypt it using ECC. After that, deploy a smart contract and continue with the encrypted PGP's key transactions in blockchain networks. Through this integration, we aim to enhance the security, ensuring both confidentiality and integrity of the PGP's key. We demonstrated that the proposed system is workable by experimental observation.

DOI： 10.1109/CANDARW60564.2023.00040

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW60564.2023.00050

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その他リンク： https://dblp.uni-trier.de/db/conf/candar/candar2023w.html#RahayuHAHKN23

掲載種別：研究論文（国際会議プロシーディングス）  

Vehicular Ad-Hoc Networks (VANETs) are a prominent technology in the drive towards establishing smart transportation systems in the Digital Transformation (DX) era. These networks provide users with critical road information for optimal route selection and accident avoidance. However, the openness of VANETs environment makes them susceptible to various cyber threats. Therefore, authenticating the entities that join the network is necessary and crucial for ensuring the security and integrity of VANET communications. Kerberos is one of the authentication protocols that ensure security, as the password and key are never directly sent among the entities. However, ensuring secure and efficient authentication, especially in VANET handovers, remains a challenge. This paper introduces an innovative authentication system for VANETs that leverages the combined power of blockchain and Kerberos. The system stores Kerberos authenticator messages in a distributed ledger within the blockchain, accessible to Trusted Authorities (TAS) and all RSUs. This approach streamlines vehicle handovers and safeguards authenticator messages against adversarial tampering. It exhibits minimal signalling overhead and authentication delay, ensuring swift and secure authentication processes. We verify the proposal's effectiveness by simulating the VANETs environment with 100 vehicles, 4 RSUs, and 1 TAS using Omnet++ with the Tsushima, Japan area map.

DOI： 10.1109/CANDARW60564.2023.00050

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW60564.2023.00040

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その他リンク： https://dblp.uni-trier.de/db/conf/candar/candar2023w.html#HossainRAHKN23

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/itc-cscc55581.2022.9894933

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/itc-cscc55581.2022.9894996

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/itc-cscc55581.2022.9895089

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/itc-cscc55581.2022.9894931

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掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/s22134909

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掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/e24060780

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掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/ijnc/ijnc12.html#NanjoSKKN22

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-Taiwan55306.2022.9869152

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2022.html#InoueMUAN22

掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/CANDAR57322.2022.00021

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2022.html#IkesakaNKKN22

掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/CANDARW57323.2022.00043

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2022w.html#IidaIKKN22

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ITC-CSCC52171.2021.9501429

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/itc-cscc52171.2021.9938141

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1007/978-3-030-72725-3_3

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/e23091168

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 電子情報通信学会  

<p>To be suitable in practice, pairings are typically carried out by two steps, which consist of the Miller loop and final exponentiation. To improve the final exponentiation step of a pairing on the BLS family of pairing-friendly elliptic curves with embedding degree 15, the authors provide a new representation of the exponent. The proposal can achieve a more reduction of the calculation cost of the final exponentiation than the previous method by Fouotsa et al.</p>

DOI： 10.1587/transfun.2020EAL2046

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その他リンク： https://dblp.uni-trier.de/db/journals/ieiceta/ieiceta104.html#NanjoSKN21

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IJNC編集委員会  

Pairings are widely used for innovative protocols such as ID-based encryption and group signature authentication. According to the recent works, the Barreto-Lynn-Scott (BLS) family of pairing-friendly elliptic curves is suggested for the pairings at the various security levels. One of the important facts is that the BLS family has fixed polynomial parameters of a field characteristic and group order in terms of an integer x_0. For practical pairing-based protocols, we have to carefully find x_0 which leads to efficient pairings, however, this search of x_0 is typically complicated. Thus, it is desired some convenient ways of finding x_0 which have advantageous for the pairings. For this reason, Costello et al. proposed simple restrictions for finding x_0 that generates the specific BLS subfamilies of curves with embedding degree k = 24 having one of the best field and curve constructions for the pairings. Since there are demands of such restrictions for the other cases of the embedding degrees, the authors extend their work and provide these for the cases of k = 2^m 3 and 3^n with arbitrary integers m, n>0 in this paper. The results will help to find new parameters which lead to one of the best performing pairings with the BLS family of curves with various k. The results also allow us to respond to change in the security levels of the pairings flexibly according to the progress in the security analyses in the future.

DOI： 10.15803/ijnc.11.2_383

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その他リンク： https://dblp.uni-trier.de/db/journals/ijnc/ijnc11.html#NanjoSKN21

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IJNC編集委員会  

In this paper, the authors focus on and propose an approach to attack a kind of pairing-friendly curves, the Barreto-Naehring (BN) curve, to accelerate the evaluation of the security level concerning the elliptic curve discrete logarithm problem (ECDLP). More precisely, this paper targets the BN curve, which is known to be a pairing-friendly curve, and Pollard's rho method based on the random-walk is adopted to attack the curve.Though Pollard's rho method with skew Frobenius mapping is known to solve the ECDLP efficiently, this approach sometimes induces the unsolvable cycle, called the fruitless cycle, and such trials must restart with a different starting point. However, any effective method to eliminate such fruitless cycles has not been proposed. Therefore, the authors focus and give the sophisticated analysis to propose an effective approach to eliminate such cycles to optimize Pollard's rho method furthermore. In addition, we confirm the effectiveness of the method by applying it to a BN curve with 12, 17, and 33-bit parameters.

DOI： 10.15803/ijnc.11.2_231

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その他リンク： https://dblp.uni-trier.de/db/journals/ijnc/ijnc11.html#MiuraKMKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9603232

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#SatoKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9602941

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#HattoriTTNKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9602954

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#EguchiMUAN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9603240

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#YoshimotoKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9603017

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#NasuKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9603146

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#MiyamotoFHYKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ICCE-TW52618.2021.9602917

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その他リンク： https://dblp.uni-trier.de/db/conf/icce-tw/icce-tw2021.html#TakahashiMAUN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDAR53791.2021.00014

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2021.html#NanjoSKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDAR53791.2021.00028

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2021.html#NanjoSKKN21a

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW53999.2021.00064

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2021w.html#NakanoseKKN21

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW53999.2021.00075

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2021w.html#EnamiKKN21

掲載種別：論文集(書籍)内論文  

DOI： 10.1515/9783110621730-006

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その他リンク： https://www.degruyter.com/document/doi/10.1515/9783110621730-006/xml

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/19361610.2019.1649534

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/19361610.2019.1669987

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掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW51189.2020.00076

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2020w.html#TangIKN20

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW51189.2020.00073

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2020w.html#NanjoSKN20

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW51189.2020.00066

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2020w.html#AkhterTNKF20

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDAR51075.2020.00029

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2020.html#MiuraMKN20

掲載種別：研究論文（国際会議プロシーディングス）  

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その他リンク： https://dblp.uni-trier.de/conf/isita/2020

掲載種別：研究論文（国際会議プロシーディングス）  

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その他リンク： https://dblp.uni-trier.de/conf/isita/2020

掲載種別：研究論文（国際会議プロシーディングス）  

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その他リンク： https://dblp.uni-trier.de/conf/isita/2020

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1007/978-3-030-58208-1_2

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その他リンク： https://dblp.uni-trier.de/db/conf/iwsec/iwsec2020.html#KoderaTKNU20

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IJNC編集委員会  

It is well-known that quadratic extension fields (QEFs) based on optimal extension fields (OEFs) are typically used for supersingular isogeny Diffie-Hellman (SIDH) key exchange protocol. On the other hand, there is a possibility of the performance improvement of SIDH by employing other attractive choices of QEFs with efficient performing arithmetics which are based on all-one polynomial extension fields (AOPFs) and extension fields with normal basis representation (EFNs). Thus, the authors confirm that the applicability of the new candidates of QEFs for SIDH and evaluate SIDH applied the possible choices of QEFs. As a result of the experiment, the authors found that the performances of SIDH applied the QEFs based on AOPF and EFN are comparable to that of the previous QEF. Moreover, one of the QEFs based on EFN result in a new efficient implementation of the SIDH with SIDH-friendly prime given as p= 2^{e_A}3^{e_B}f+1 where e_A, e_B and $f$ are positive integers.

DOI： 10.15803/ijnc.10.2_227

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 電子情報通信学会  

<p>A quadratic extension field (QEF) defined by F₁ = F_p[α]/(α²+1) is typically used for a supersingular isogeny Diffie-Hellman (SIDH). However, there exist other attractive QEFs F_i that result in a competitive or rather efficient performing the SIDH comparing with that of F₁. To exploit these QEFs without a time-consuming computation of the initial setting, the authors propose to convert existing parameter sets defined over F₁ to F_i by using an isomorphic map F₁ → F_i.</p>

DOI： 10.1587/transfun.2020TAL0002

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その他リンク： https://dblp.uni-trier.de/db/journals/ieiceta/ieiceta103.html#NanjoSKN20

掲載種別：研究論文（学術雑誌）  

DOI： 10.15803/ijnc.10.2_144

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/CANDARW.2019.00074

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019w.html#TaketaKTKNTU19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In recent years, pairing encryption is receiving a lot of attention since it enables many innovative and multi-functional cryptographic applications based on pairing e.g. searchable encryption, broadcast encryption and so on. Pairing is a map from two additive rational point groups mathbb{G}{1}, mathrm{G}{2} to a multiplicative group mathbb{G}{3}, however, it requires complexity computation. Therefore, the author tries to develop a 128-bit security level pairing library ELiPS (Efficient Library for Pairing Systems) that incorporates various high-speed methods using BLS curves. As a result, scalar multiplications on mathbb{G}{1} and mathbb{G}{2}, exponentiation on mathbb{G}{3}, and optimal-ate pairing can be computed in 0.42[ms], 0.79[ms], 1.13[ms], and 3.12[ms], respectively.

DOI： 10.1109/ITC-CSCC.2019.8793376

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In recent years, the number of companies are adopting cloud computing service for outsourcing is increasing. On the other hand, there are threats that are like falsification or leakage to data to be kept secret. Therefore, the technologies for managing encrypted data are the attractive topics in the cryptographic field. Among them, functional encryption which is constructed with pairing-based cryptography is closing to the practical stage because pairing operation is getting faster by the recent study of pairing. In addition, there are some pairing libraries which allow a user to introduce the pairing-based cryptography to their system. Nevertheless, they have some differences in several operations. In this paper, we reconstruct pairing-based homomorphic encryption by focusing on features of libraries and examine the performance evaluations of them.

DOI： 10.1109/ITC-CSCC.2019.8793446

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In recent years, CAN is spread widely as the in-vehicle network. However, CAN protocol does not guarantee the security for traffics against falsification and spoofing. Therefore, the MAC is required for CAN so as to communicate exactly. MAC is the countermeasure for falsification and spoofing using the secret key. The problem is a method of delivering the secret key securely. This paper proposes a method to update the secret key using broadcast encryption over a non-supersingular elliptic curve. The method is implemented on Raspberry Pi and experimentally find out to be able to update the secret key efficiently.

DOI： 10.1109/ITC-CSCC.2019.8793298

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper focuses on the computational security of elliptic curve discrete logarithm (ECDLP), which can evaluate by an actual attack. The authors apply Pollard's rho method to a Barreto-Naehrig curve with minimum parameters for solving an ECDLP. An analysis of the structure for all combinations of a select of seed and starting points are given. Then, we propose the method for selecting a set of efficient seed points for a random walk for the rho method.

DOI： 10.1109/ITC-CSCC.2019.8793449

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Block Turbo Decodings (BTDs) with Soft-In Soft-Out (SISO) decodings for two dimensional product codes of linear codes can achieve good error performance, however, large computational complexity of the BTDs can be a problem. Therefore, to reduce the computational complexity, quantization methods can be employed for the BTDs by sacrificing the error performance. In this paper, a study on design for low level quantizers for the BTD with S1SO Ordered Statistics Decoding for product codes of binary linear code is shown. From simulation results for a 4-level quantizer, the authors propose a new 5-level quantizer. The proposed 5-level quantizer achieves better error performance than 4-level quantizer.

DOI： 10.1109/ITC-CSCC.2019.8793409

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

A pseudorandom sequence has an inseparable role in various types of security applications. Especially, the linear complexity of a sequence is a measure of the randomness that should be large for secureness of a system. This paper considers the boundary of linear complexity of a geometric sequence called NTU sequence which is generated with a uniformization technique.

DOI： 10.1109/ICCE-TW46550.2019.8992029

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Pseudorandom sequences of having a uniform distribution of bit patterns and high linear complexity play a key role in many security applications. However, only a few pseudorandom sequence possesses both of these vital features. In this paper, the authors propose and evaluate a geometric sequence that has a uniform distribution and high linear complexity.

DOI： 10.1109/ICCE-TW46550.2019.8991711

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Random sequences play important roles in many security applications. Several security protocols have been developed based on random sequences. Hence, their generation is one of the topic of interests among many cryptographic researchers. Previously, the authors proposed a pseudo random sequence over odd characteristic field which is generated by applying primitive polynomial, trace function and Mobius function. Some important properties such as period, autocorrelation and cross-correlation have been presented in previous work. Randomness is generally measured by statistical tests and NIST Statistical Test Suite (NIST STS) is one of the most popular tools for randomness analysis. In this work, the randomness of the generated sequence is investigated by NIST STS.

DOI： 10.1109/ICCE-TW46550.2019.8992033

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掲載種別：研究論文（国際会議プロシーディングス）  

© 2018 IEICE. In this research, the choice of the parameter of the Montgomery trick in Pollard's Rho method to solve the elliptic curve discrete logarithm problem for Barreto-Naehrig (BN) curves is shown. The average number of generated rational points per unit time is chosen as a measure of the effectiveness of the choice of the parameter of the Montgomery trick. The results are derived from a sufficient number of experiments with several BN curves.

DOI： 10.23919/ISITA.2018.8664242

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

© 2018 IEICE. In this research, the choice of the parameter for a method to generate distinguished rational points in Pollard's Rho method to solve the elliptic curve discrete logarithm problem for Barreto-Naehrig (BN) curves is shown. The structures of random walk paths are confirmed by experiments for several BN curves. From the results, the authors clarify the conditions in which the Rho method does not stop during an attack, and the authors also show an indication for the choice of the parameter for the method to generate distinguished points with large bits of ECDLP.

DOI： 10.23919/ISITA.2018.8664405

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その他リンク： https://dblp.uni-trier.de/db/conf/isita/isita2018.html#IkutaJKKKN18a

記述言語：日本語   出版者・発行元：日本ソフトウェア科学会  

IoT機器の情報セキュリティを保証するために不可欠な技術の1つである暗号技術に関する実践的な演習科目を開発した．開発した演習は，現代暗号の基礎となっている代数学や離散数学の座学，暗号アルゴリズムのハードウェア実装，そして実装した暗号ハードウェアへのサイドチャネル攻撃実験で構成される．本演習では，暗号アルゴリズムの教科書的な知識を学ぶだけでなく，受講生自身が暗号アルゴリズムを市販ハードウェアへ実装し，その実装ハードウェアへの攻撃を実行することで，実用上の脅威を体験し，そのような脅威を考慮して暗号アルゴリズムを実装する重要性を理解することを目標としている．本演習を学部3, 4年生50名に対して実施し，ほぼ全員がこの目標を達成した．さらに受講生へのアンケートによると，ほぼ全ての受講生が暗号技術に関する実践力向上を実感する結果を得た．

DOI： 10.11309/jssst.36.30

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In this paper, we give some important characteristics of Knuth's quadratic congruential sequences with a particular modulus as a pseudorandom number generator. For modulus m = 2W p where p is an odd prime, we derive some periodic relations of the sequence by using analysis results shown by Iwasaki and Umeno for their one-stroke polynomial. Accordingly, we have theoretical analysis for randomness of these sequences and evaluate pseudorandom number outputs by these sequences by the NIST statistical tests.

DOI： 10.1109/IWSDA46143.2019.8966096

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その他リンク： https://dblp.uni-trier.de/db/conf/iwsda/iwsda2019.html#MiyazakiAKUN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

The increment of opportunities for using machine learning (ML) technologies has brought a new threat to cryptosystems. As a remarkable example, the ML technologies have gradually been employed in the side-channel attack (SCA) to obtain sensitive information. In this paper, the authors focus on the structure of a masked S-Box in AES, which aims to equip the SCA resistance even for the attacks using the ML technologies. More precisely, this paper analyzes the mathematical structure of the inverse operation over F(24)2 which is an isomorphic field for obtaining efficient arithmetic for the AES, so that all functions in the encryption scheme can handle masked data as it is. The mathematical structure is realized by introducing several mathematical tools such as the Gauss periods and the Itoh-Tsujii inversion algorithm, and as a result, we clarified the factors of the coefficients of A-1 for an element A F(24)2. It enables us to generate the corresponding element directly, which allows canceling the mask even after processing the SubBytes.

DOI： 10.1109/CANDAR.2019.00027

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019.html#KoderaTKN19

掲載種別：論文集(書籍)内論文   出版者・発行元：Springer International Publishing  

This paper considers a new construction of a keyword search including partial matching on an encrypted document. Typically, an index-based searchable symmetric encryption has been investigated. However, it makes a partial keyword matching difficult without a designated trapdoor. Thus, our objective is to propose a keyword search scheme which enables us to search a part of a keyword only by building trapdoors of each original keyword. The main idea is to insulate each character of a keyword into a bitstream of the sequence generated by a pseudorandom number generator. It achieves a partial search by giving a restriction on the length of a keyword.

DOI： 10.1007/978-3-030-17982-3_19

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掲載種別：研究論文（学術雑誌）   出版者・発行元：ASTES Journal  

The distribution of bit patterns is an important measure to check the randomness of a sequence. The authors of this paper observed this crucial property in a binary sequence which generated by using a primitive polynomial, trace function, and Legendre symbol defined over the sub extension field. The authors create a new dimension in the sequence generation research area by considering the sub extension field, whereas all our previous works are focused in the prime field. In terms of distribution of bit patterns property, this research work has notable outcomes more specifically the binary sequence (defined over the sub extension field) holds much better (close to uniform) bit distribution than the previous binary sequence (defined over the prime field). Furthermore, the authors theoretically proved the distribution of bit property in this paper.

DOI： 10.25046/aj040246

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掲載種別：研究論文（国際会議プロシーディングス）  

© Springer Nature Switzerland AG 2019. This paper proposes two attractive classes of Barreto-Naehrig curve for ate-based pairing by imposing certain condition χ ≡ 7, 11 (mod 12) on the integer χ that parameterizes the curve settings. The restriction results in an unparalleled way to determine a BN curve, its twisted curve coefficients, and obvious generator points. The proposed χ ≡ 11 (mod 12) are found to be more efficient than χ ≡ 7 (mod 12) together with pseudo 8-sparse multiplication in Miller's algorithm. The authors also provide comparative implementations for the proposal.

DOI： 10.1007/978-3-030-17982-3_5

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

This paper discusses the conditions of fruitless cycles for Pollard's rho method with skew Frobenius mapping for elliptic curve discrete logarithm problem (ECDLP) over a Barreto-Naehrig (BN) curve. When a random walk pass achieves a fruitless cycle, the random walk pass must restart with a different starting point. There can be several methods to eliminate fruitless cycles of short lengths for BN curves based on the construction of a random walk table. Therefore, in this research, the authors give an analysis of the previous methods for a BN curve of order 349 with the mapping with experiments. The results show that several fruitless cycles of length two and three cannot be eliminated by the previous methods. The authors investigated the reason for degradation. As a result of the analysis, a new condition where a part of the fruitless cycles of any lengths occur is derived, and a new method to eliminate the fruitless cycles is proposed.

DOI： 10.1109/CANDARW.2019.00068

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

Curve25519 has been used in various security protocols for its efficiency and rapidity. However, Curve25519 is known to have rational points whose orders are 2, 4, and 8. In this research, the authors focus on rational points of order 4 and demonstrate a side-channel attack (SCA) against a scalar multiplication algorithm for Curve25519. It purposes to compare two scalar multiplication algorithms in terms of the difficulty of estimating a secret key via the SCA, where the algorithms are differentiated whether it uses a conditional swap function or not. Furthermore, we examine to attack an open-source library for Arduino UNO which includes the scalar multiplication algorithm using a conditional swap function in practice. Since this library takes a countermeasure against the SCA during key exchange, we can use this secure library as a protocol tool. However, there is a threat when we implement a scalar multiplication by using some functions in this library without considering the SCA.

DOI： 10.1109/CANDAR.2019.00040

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019.html#YoshimotoUKKN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

Among the increasing evolution of IoT devices, practical applications need reliable secure protocols to communicate with each other. A major issue for modern cryptosystems is an implementation of secure and trustworthy mechanisms to rely on. A side-channel attack against these cryptosystems may overturn the guarantee of security against conventional cyber-attacks. Elliptic curve cryptography is public-key cryptography based on elliptic curves, and one of the well-known curves is Curve25519 which is used for TLS protocols as a recommended curve. This curve is mainly implemented on limited resource devices such as microcontrollers. However, this curve poses a weakness for low-order points during a Diffie-Hellman key exchange is employed. This research demonstrates possible exploitation of a threat of order 8 rational points of Curve25519 and shows results of the side-channel attacks using order 8 rational points on an embedded system. The results indicate the order 8 rational points might be applied to key extraction as attacker sides.

DOI： 10.1109/CANDAR.2019.00037

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019.html#UetakeYKWKN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

It is well-known that the class of binomial extension fields is widely used to construct quadratic extension fields (QEFs) of supersingular isogeny Diffie-Hellman (SIDH) key exchange protocol. There is a possibility to improve the performance of SIDH by employing other classes of QEFs, i.e., extension fields with normal basis and all-one polynomial extension fields, without sacrificing the range of primes. In this paper, the authors confirm that the applicability of the other classes for SIDH and evaluate the computational complexity of the large-degree isogenies required for SIDH. The results of the experiments show that the performances with the classes are comparable to the QEF with a binomial x2+1.

DOI： 10.1109/CANDAR.2019.00030

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019.html#NanjoSKN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In this paper, we focus on binary sequences obtained from piecewise logistic map over integers, and show the relation between the Lyapunov exponents of the maps and results of the NIST tests for the sequences. When the Lyapunov exponent is a negative value, we confirm that the branch diagram is sparse and the bit occurrence rate is also greatly biased. We also give a sample of that the positive/negative signs of the Lyapunov exponents mostly coincide on the evaluations of the NIST tests. From the branching diagram of the piecewise logistic map, we can moreover find that there are many good pseudorandom sequences generated by the individual control parameters of the map.

DOI： 10.1109/IWSDA46143.2019.8966109

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その他リンク： https://dblp.uni-trier.de/db/conf/iwsda/iwsda2019.html#EguchiMAUN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

Block Turbo Decodings (BTDs) with Soft-In SoftOut (SISO) decodings for two-dimensional product codes of linear codes can achieve good error performance. However, since large computational complexity of the BTDs can be a problem, a method which can reduce average computational complexity is needed. In this research, the authors focus on an early termination condition as the method for the reduction on the computational complexity. From the tendency of the output of SISO ordered statistics decoding, a condition is proposed. Based on simulation results for the two-dimensional product code of the (32,26,4) Reed-Muller code, analysis on a parameter of the condition are given. The results show that the computational complexity can be reduced to more than one fourth at the SN ratios higher than 7[dB] of Eb/No without degradation on error performance by choosing an appropriate parameter.

DOI： 10.1109/CANDARW.2019.00080

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2019w.html#KageyamaINKKN19

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE COMPUTER SOC  

In this paper, we propose a new pseudo random binary sequence generated from a primitive polynomial over an extension field. The sequence has maximum period and high linear complexity suitable for security applications. While generation, a new mapping function is proposed which is faster than conventional trace map and translates extension field elements to prime field elements. The output of mapping function is a p-ary sequence with elements 0~ (p-1) that is balanced in pattern distribution and has ideal autocorrelation. Then, a binarization method is utilized to derive binary sequence from p-ary sequence. Period, autocorrelation, linear complexity and computation time of the proposed sequence are studied and experimental results are presented. Finally, the efficiency of the proposal is verified by comparing with existing sequences in terms of period, linear complexity and generation time for sequences of different length.

DOI： 10.1109/CANDARW.2019.00076

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Research and development of automatic driving technology has been actively conducted in recent years. Under this background, it is considered that the car parking problem is expected to be developed for supporting drivers to complete automatic parking. Many parking lots in an urban area prepare parking spaces with asphalt road surface drawn by white paint. Research to recognize parking spaces using camera images has been conducted so far. However, camera images are known to be not robust to environmental conditions such as nighttime and a backlight. Therefore, a method of recognizing parking spaces is proposed so that it can be used even when the use time is day or night, irrespective of whether the road surface is dry or wet. In the proposed method, the road surface is classified using the statistical model of the received light intensity value of laser range scanner. Then, the target parking position is estimated by Hough transformation.

DOI： 10.1109/SII.2019.8700344

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その他リンク： https://dblp.uni-trier.de/db/conf/sii/sii2019.html#KamiyamaMOWN19

掲載種別：研究論文（学術雑誌）  

The authors propose a well balanced multi-value sequence (including a binary sequence). All the sequence coefficients (except the zero) appear almost the same in number, thus, the proposed sequence is so called the well balanced sequence. This paper experimentally describes some prominent features regarding a sequence, for instance, its period, autocorrelation, and cross-correlation. The value of the autocorrelation and cross-correlation can be explicitly given by the authors formulated theorems. In addition, to ensure the usability of the proposed multi-value sequence, the authors introduce its flexibility by making it a binary sequence. Furthermore, this paper also introduces a comparison in terms of the linear complexity and distribution of bit patterns properties with their previous works. According to the comparison results, the proposed sequence holds better properties compared to our previous sequence.

DOI： 10.25046/aj040423

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Scientific Research Publishing, Inc.  

DOI： 10.4236/jis.2019.103008

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

© 2018 IEEE. Pairing-based protocols are getting popular in many cryptographic applications. Pairing algorithms involve computations on elements in all three pairing groups, G 1 , G 2 and G 3 ; however, most protocols usually require additional scalar multiplication and exponentiation in any of these three groups. The Gallant-Lambert-Vanstone (GLV) method is an elegant technique to accelerate the scalar multiplication which can reduce the number of elliptic curve doubling by using Straus-Shamir simultaneous multi-scalar multiplication technique. However, efficiently computable endomorphisms are required to apply GLV for the elliptic curves. This paper shows the GLV technique by deriving efficiently computable endomorphism for Kachisa-Schaefer-Scott (KSS) curve defined over degree 16 extension field. In addition, the authors show explicit formulas to compute the GLV method together with Straus-Shamir simultaneous multi-scalar multiplication technique for 2, 4 and 8 dimensions in G 2 group. The comparative implementation shows that dimension 4 gives faster computational time than dimension 8 and 2.

DOI： 10.1109/CANDAR.2018.00021

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2018.html#KhandakerNKN18

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

© 2018 IEEE. In recent years, many innovative cryptography protocols based on the pairing. Finding out an efficient extension field construction is one of the prerequisites for a practical pairing implementation. The author tries to find an elegant extension field construction which will result in efficient pairing over Barreto-Naehrig (BN) curve. In this paper, two construction methods are considered for extension field of degree 12, and one of them results in an efficient exponentiation and the other enables to compute faster Miller loop than the former one. Therefore, a method which uses a basis conversion matrix between the two extension field is proposed. In comparison to the performance of Aranha et al.'s towering, the proposed implementation results in the efficient exponentiation in a multiplicative group, although pairing cost is slightly increased.

DOI： 10.1109/CANDARW.2018.00087

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2018w.html#NanjoKKN18

掲載種別：研究論文（国際会議プロシーディングス）  

To identify semiconductor devices that are dominant noise sources at low cost in order to reduce electromagnetic interference (EMI), we propose a method based on a noise source amplitude modulation technique and correlation analysis (NSM-CA). In this study, we applied the NSM-CA method to a printed circuit board (PCB) with multiple integrated circuits (ICs) and identified ICs dominantly contributing to EM emission. The switching currents produced in three of the ICs were modulated in amplitude with three different modulation signals. The noise source amplitude modulation was implemented in an FPGA, mounted on a PCB, by using three pseudorandom binary sequences (PRBSs) as modulation signals. During the modulations, EM emission was measured at frequencies where the emission exceeded the limit of EMI regulation. The temporal variation in the measured emission was correlated with each of the PRBSs. The ranking of the contributions of the ICs to the emission was determined by means of the resultant correlation coefficients. According to the ranking, the dominant ICs to which a combination of EMI reduction techniques should be primarily applied were identified. Moreover, we applied an EMI reduction technique to the dominant ICs and found a larger reduction in emission than when the technique was applied to low priority ICs.

DOI： 10.1109/EMCEurope.2018.8485011

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Cryptography is one of the most important elements on the information security. In this paper, we propose a construction method of a long-period binary sequence with good randomness which plays an important role in cryptography. We generate the sequence by combining two types of binary sequences; one is the m-sequence and the other is a quadratic congruential sequence proposed by Knuth. It is well known that the m-sequence has good statistical properties, and Knuth's method can generate a long period sequence. However, both of these sequences cannot pass the almost NIST statistical tests by stand-alone. We derive a binary sequence combining these two sequences. In addition; we also consider the reasons why the proposed sequence has good randomness properties.

DOI： 10.1109/ICCE-China.2018.8448725

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

With the spread of loT, it is necessary to implement of encryption and decryption in order to secure information handled by each device. We focus on generating a sequence having random number property for a microcomputer with a short available bit length. We propose binary sequences combined from two random number sequences of 16 bits or less, one is an interleaving operation and the other is a combination by using a Gray code. In this paper, we discussed about how to generate a sequence and random number properties.

DOI： 10.1109/ICCE-China.2018.8448887

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper presents an efficient arithmetic in extension field based on Cyclic Vector Multiplication Algorithm that reduces calculation costs over cubic extension for elliptic curve pairing cryptography. In addition, we evaluate the calculation costs compared to Karatsuba-based method.

DOI： 10.1109/ICCE-China.2018.8448573

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

Copyright © 2018 The Institute of Electronics, Information and Communication Engineers. Generalized Minimum Distance (GMD) decoding is a well-known soft-decision decoding for linear codes. Previous research on GMD decoding focused mainly on unquantized AWGN channels with BPSK signaling for binary linear codes. In this paper, a study on the design of a 4-level uniform quantizer for GMD decoding is given. In addition, an extended version of a GMD decoding algorithm for a 4-level quantizer is proposed, and the effectiveness of the proposed decoding is shown by simulation.

DOI： 10.1587/transfun.E101.A.1235

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その他リンク： https://dblp.uni-trier.de/db/journals/ieicet/ieicet101a.html#UedaIKKAN18

掲載種別：研究論文（国際会議プロシーディングス）  

© 2017 IEEE. The security of Internet of Things (IoT) devices is one of the most important problems. The processing ability of IoT devices is limited, therefore a more light-weight and secure cryptography is necessary. This paper shows the implementation of 256-bit Elliptic Curve Cryptography (ECC) on an 8-bit microcontroller by applying towering for extension field of degree 32. The authors use a twisted Montgomery curve with a Montgomery ladder which enables fast calculations without inverse elements. In addition to that, this implementation is considered resistant to the Side Channel Attack (SCA) since it applies the Montgomery ladder for the scalar multiplication (SCM). This ECC implementation on Arduino UNO, an 8-bit microcontroller board, takes 3 seconds for an SCM which can be made faster by careful assembly implementation.

DOI： 10.1109/CANDAR.2017.90

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1587/transfun.E101.A.1525

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記述言語：英語   出版者・発行元：一般社団法人 日本機械学会  

DOI： 10.1109/SMC.2018.00296

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CiNii Article

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その他リンク： https://dblp.uni-trier.de/db/conf/smc/smc2018.html#MorishitaMNW18

掲載種別：研究論文（学術雑誌）  

DOI： 10.1587/transfun.E101.A.1235

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

Pairing-based protocols are getting popular in many cryptographic applications. Pairing algorithms involve computations on elements in all three pairing groups, G 1 , G 2 and G 3 ; however, most protocols usually require additional scalar multiplication and exponentiation in any of these three groups. The Gallant-Lambert-Vanstone (GLV) method is an elegant technique to accelerate the scalar multiplication which can reduce the number of elliptic curve doubling by using Straus-Shamir simultaneous multi-scalar multiplication technique. However, efficiently computable endomorphisms are required to apply GLV for the elliptic curves. This paper shows the GLV technique by deriving efficiently computable endomorphism for Kachisa-Schaefer-Scott (KSS) curve defined over degree 16 extension field. In addition, the authors show explicit formulas to compute the GLV method together with Straus-Shamir simultaneous multi-scalar multiplication technique for 2, 4 and 8 dimensions in G 2 group. The comparative implementation shows that dimension 4 gives faster computational time than dimension 8 and 2.

DOI： 10.1109/CANDAR.2018.00021

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

DOI： 10.1109/CANDARW.2018.00087

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In this research, the choice of the parameter for a method to generate distinguished rational points in Pollard's Rho method to solve the elliptic curve discrete logarithm problem for Barreto-Naehrig (BN) curves is shown. The structures of random walk paths are confirmed by experiments for several BN curves. From the results, the authors clarify the conditions in which the Rho method does not stop during an attack, and the authors also show an indication for the choice of the parameter for the method to generate distinguished points with large bits of ECDLP.

DOI： 10.23919/ISITA.2018.8664405

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In this research, the choice of the parameter of the Montgomery trick in Pollard's Rho method to solve the elliptic curve discrete logarithm problem for Barreto-Naehrig (BN) curves is shown. The average number of generated rational points per unit time is chosen as a measure of the effectiveness of the choice of the parameter of the Montgomery trick. The results are derived from a sufficient number of experiments with several BN curves.

DOI： 10.23919/ISITA.2018.8664242

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Simeck family block cipher was proposed in CHES 2015. It is a kind of lightweight block cipher provide various block and key size. In this paper, we proposed efficient parallel implementation of Simeck with GPGPU by using OpenCL and present performance of Simeck parallel implementation.

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掲載種別：研究論文（学術雑誌）  

In the age of IoT, pairing-based cryptography (PBC) can play an important role as a public key cryptography since it enables several innovative protocols such as anonymous encryption, certificate less authentication and so on. However, due to the computation complexity, PBC is often regarded computationally unfeasible for IoT devices. Therefore, this paper tries to push that limit by efficiently calculating pairing operation together with scalar multiplication and exponentiation over Barreto-Naehrig (BN) curve by applying the state of art techniques. In addition to the theoretic explanation of the applied techniques, the authors also show a high-level implementation using C programming on a raspberry pi model 3 B, instead of hardware specific implementation.

DOI： 10.12720/jcm.13.2.88-93

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

DOI： 10.1109/CANDARW.2018.00061

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掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

With the matter of secure communication between devices, and especially for IoT devices, more and more applications need trustful protocols to communicate using public key cryptography. Elliptic curve cryptography is nowadays a very secure and efficient public key cryptography method. One of the most recent and secure curve is Curve25519 and one of its failure is attack on low-order elements during a Diffie-Hellman key exchange. This document demonstrates that an attack using an order 4 point is possible on an embedded system with a simple power analysis, pointing out every IoT using Curve255119 as a cryptographic method, a potential target to side-channel attacks.

DOI： 10.23919/ISITA.2018.8664293

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その他リンク： https://dblp.uni-trier.de/db/conf/isita/isita2018.html#UetakeSKNWD18

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

The development of the autonomous driving and the connected services severely increase security threats on old automotive technologies that are still present on-board vehicles since the long incremental process were employed. For example, the Controller Area Network (CAN) bus, which was standardized in 1991, can be connected to modern Linux embedded computer nodes where evil attacker might be able to exploit a vulnerability on the nodes. However, it is not easy to implement countermeasures on the CAN bus, since the strict requirements and limited performances of CAN specification. That is one of the major reason for the new standard CAN Flexible Data-rate (CAN FD) has been released in 2012 by Bosch to fill the gap between these challenges and the CAN protocol. In this research, a new simple authentication protocol for CAN FD is proposed, and the protocol is evaluated by experiments. The results show that the proposed protocol prevents infected nodes from usurping identity of a critical node and forge messages, with practical computational complexity on modern low-power embedding boards.

DOI： 10.1109/CANDARW.2018.00057

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2018w.html#CarelIKNA18

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

To identify semiconductor devices that are dominant noise sources at low cost in order to reduce electromagnetic interference (EMI), we propose a method based on a noise source amplitude modulation technique and correlation analysis (NSM-CA). In this study, we applied the NSM-CA method to a printed circuit board (PCB) with multiple integrated circuits (ICs) and identified ICs dominantly contributing to EM emission. The switching currents produced in three of the ICs were modulated in amplitude with three different modulation signals. The noise source amplitude modulation was implemented in an FPGA, mounted on a PCB, by using three pseudorandom binary sequences (PRBSs) as modulation signals. During the modulations, EM emission was measured at frequencies where the emission exceeded the limit of EMI regulation. The temporal variation in the measured emission was correlated with each of the PRBSs. The ranking of the contributions of the ICs to the emission was determined by means of the resultant correlation coefficients. According to the ranking, the dominant ICs to which a combination of EMI reduction techniques should be primarily applied were identified. Moreover, we applied an EMI reduction technique to the dominant ICs and found a larger reduction in emission than when the technique was applied to low priority ICs.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper focuses on the Maximum Order Complexity of a pseudorandom sequence for security applications called NTU sequence. It shows the maximum feature on the nonlinear property and several properties have been theoretically proven. However, the NTU sequence requires a uniformization technique to overcome the drawback on its bits distribution. The technique has already proposed but the non-liear feature still has not investigated. Therefore, this paper evaluates the affects on the non-linear feature of the original NTU sequence by using Maximum Order Complexity.

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掲載種別：研究論文（学術雑誌）   出版者・発行元：MECS Publisher  

DOI： 10.5815/ijcnis.2017.09.07

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Institute of Electrical and Electronics Engineers Inc.  

In this paper, we will propose a digital watermarking for voice signals recorded by a digital voice recorder especially in conferences. We will discuss some requirements for detecting falsifications in the voice signal, because the conference record has the probability that a conclusion is changed for only a falsification in a little time interval. Next, we will show a method of locating an altered place in the voice signal and a new idea applying a white Gaussian noise for guarantee of the valid voice signal without falsification. One characteristic of our proposal is an agitation depending on a peak spectrum for making it difficult to illegally change the embedded watermark.

DOI： 10.1109/ICCE-China.2017.7991091

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

© 2017 IEEE. The Internet of Things (IoT) provides much convenient life for us, at the same time it has brought threats for our privacy. In this context, secure and efficient cryptosystem is required to which pseudorandom sequence plays an important role. Especially, the distribution of bit patterns in the pseudorandom sequence is one of important security aspects. This paper especially focuses on the bit patterns and the distribution in an NTU sequence. As a result of a lot of observation, an important assumption about the distribution of bit patterns in an NTU sequence is introduced. It will help to obtain the balanced NTU sequence in order to enhance the security of cryptosystem on IoT communications.

DOI： 10.1109/ICCE-China.2017.7991033

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掲載種別：研究論文（国際会議プロシーディングス）  

© 2017 IEEE. In this paper, the authors apply two modular exponentiation algorithms such as left-to-right binary method and Montgomery powering ladder algorithm on Raspberry Pi and evaluate their security against Side-channel attack.

DOI： 10.1109/ICCE-China.2017.7991108

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

The authors in this paper have proposed a multi-value sequence generated by a primitive polynomial, trace function, k-th power residue symbol, and a certain mapping function over the proper sub extension field. Here, the trace function actually maps an element of the extension field to an element of the proper sub extension field, which is actually a vector space. The distribution of numbers within the sequence becomes more balanced by considering the proper sub extension field. In addition, its period and autocorrelation properties also observed in this paper.

DOI： 10.1109/ICCE-China.2017.7991089

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER INTERNATIONAL PUBLISHING AG  

The security of cryptographic protocols which are based on elliptic curve cryptography relies on the intractability of elliptic curve discrete logarithm problem (ECDLP). In this paper, the authors describe techniques applied to solve 114-bit ECDLP in Barreto-Naehrig (BN) curve defined over the odd characteristic field. Unlike generic elliptic curves, BN curve holds an especial interest since it is well studied in pairing-based cryptography. Till the date of our knowledge, the previous record for solving ECDLP in a prime field was 112-bit by Bos et al. in Certicom curve ‘secp112r1’. This work sets a new record by solving 114-bit prime field ECDLP of BN curve using Pollard’s rho method. The authors utilized sextic twist property of the BN curve to efficiently carry out the random walk of Pollard’s rho method. The parallel implementation of the rho method by adopting a client-server model, using 2000 CPU cores took about 6 months to solve the ECDLP.

DOI： 10.1007/978-3-319-78556-1_13

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

The security of Internet of Things (IoT) devices is one of the most important problems. The processing ability of IoT devices is limited, therefore a more light-weight and secure cryptography is necessary. This paper shows the implementation of 256-bit Elliptic Curve Cryptography (ECC) on an 8-bit microcontroller by applying towering for extension field of degree 32. The authors use a twisted Montgomery curve with a Montgomery ladder which enables fast calculations without inverse elements. In addition to that, this implementation is considered resistant to the Side Channel Attack (SCA) since it applies the Montgomery ladder for the scalar multiplication (SCM). This ECC implementation on Arduino UNO, an 8-bit microcontroller board, takes 3 seconds for an SCM which can be made faster by careful assembly implementation.

DOI： 10.1109/CANDAR.2017.90

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/IWSDA.2017.8097082

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/IWSDA.2017.8095741

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/IWSDA.2017.8095739

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

DOI： 10.1109/CANDAR.2017.86

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER INTERNATIONAL PUBLISHING AG  

Acceleration of a pairing calculation of an Ate-based pairing such as Optimal Ate pairing depends not only on the optimization of Miller algorithm's loop parameter but also on efficient elliptic curve arithmetic operation and efficient final exponentiation. Some recent works have shown the implementation of Optimal Ate pairing over Kachisa-Schaefer-Scott (KSS) curve of embedding degree 18. Pairing over KSS curve is regarded as the basis of next generation security protocols. This paper has proposed a pseudo 12-sparse multiplication to accelerate Miller's loop calculation in KSS curve by utilizing the property of rational point groups. In addition, this papers has showed an enhancement of the elliptic curve addition and doubling calculation in Miller's algorithm by applying implicit mapping of its sextic twisted isomorphic group. Moreover this paper has implemented the proposal with recommended security parameter settings for KSS curve at 192 bit security level. The simulation result shows that the proposed pseudo 12-sparse multiplication gives more efficient Miller's loop calculation of an Optimal Ate pairing operation along with recommended parameters than pairing calculation without sparse multiplication.

DOI： 10.1007/978-3-319-53177-9_11

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その他リンク： https://dblp.uni-trier.de/db/conf/icisc/icisc2016.html#KhandakerONSD16

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

The Internet of Things (IoT) provides much convenient life for us, at the same time it has brought threats for our privacy. In this context, secure and efficient cryptosystem is required to which pseudorandom sequence plays an important role. Especially, the distribution of bit patterns in the pseudorandom sequence is one of important security aspects. This paper especially focuses on the bit patterns and the distribution in an NTU sequence. As a result of a lot of observation, an important assumption about the distribution of bit patterns in an NTU sequence is introduced. It will help to obtain the balanced NTU sequence in order to enhance the security of cryptosystem on IoT communications.

DOI： 10.1109/ICCE-China.2017.7991033

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In this paper, the authors apply two modular exponentiation algorithms such as left-to-right binary method and Montgomery powering ladder algorithm on Raspberry Pi and evaluate their security against Side-channel attack.

DOI： 10.1109/ICCE-China.2017.7991108

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掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Springer  

In this paper, we revisited the parallel implementation of SIMON and SPECK block ciphers. The performances of SIMON and SPECK are significantly improved by using ARM NEON SIMD (Single Instruction Multiple Data) parallel computing and OpenMP SIMT (Single Instruction Multiple Thread). We optimized the implementation on ARM NEON architecture. For optimized NEON, we reduced the number of registers for round key and increased the number of registers for plaintexts. Furthermore, we proposed the efficient forward and backward alignment methods. Finally, we maximize the performance by using SIMT (Single Instruction Multiple Threads). In the case of performance of proposed methods and proposed methods with SIMT, SIMON 128/128 encryption within 32.4, 14.3 cycles/byte, SIMON 128/192 encryption within 30.1, 15.9 cycles/byte, SIMON 128/256 encryption within 32.4, 16.9 cycles/byte, SPECK 128/128 encryption within 9.7, 5.1 cycles/byte, SPECK 128/192 encryption within 10.4, 5.6 cycles/byte, SPECK 128/256 encryption within 11.0, and 5.6 cycles/byte respectively on ARM Cortex-A53 environment.

DOI： 10.1007/978-3-319-93563-8_24

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER INTERNATIONAL PUBLISHING AG  

Efficiency of the next generation pairing based security protocols rely not only on the faster pairing calculation but also on efficient scalar multiplication on higher degree rational points. In this paper we proposed a scalar multiplication technique in the context of Ate based pairing with Kachisa-Schaefer-Scott (KSS) pairing friendly curves with embedding degree k = 18 at the 192-bit security level. From the systematically obtained characteristics p, order r and Frobenious trace t of KSS curve, which is given by certain integer z also known as mother parameter, we exploit the relation #E(F-p) = p + 1-t mod r by applying Frobenius mapping with rational point to enhance the scalar multiplication. In addition we proposed z-adic representation of scalar s. In combination of Frobenious mapping with multi-scalar multiplication technique we efficiently calculate scalar multiplication by s. Our proposed method can achieve 3 times or more than 3 times faster scalar multiplication compared to binary scalar multiplication, sliding-window and non-adjacent form method.

DOI： 10.1007/978-3-319-56549-1_19

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その他リンク： https://dblp.uni-trier.de/db/conf/wisa/wisa2016.html#KhandakerNSD16

掲載種別：研究論文（国際会議プロシーディングス）  

© Springer International Publishing AG 2017. Efficiency of the next generation pairing based security protocols rely not only on the faster pairing calculation but also on efficient scalar multiplication on higher degree rational points. In this paper we proposed a scalar multiplication technique in the context of Ate based pairing with Kachisa-Schaefer-Scott (KSS) pairing friendly curves with embedding degree k = 18 at the 192-bit security level. From the systematically obtained characteristics p, order r and Frobenious trace t of KSS curve, which is given by certain integer z also known as mother parameter, we exploit the relation #E(F p) = p+1−t mod r by applying Frobenius mapping with rational point to enhance the scalar multiplication. In addition we proposed z-adic representation of scalar s. In combination of Frobenious mapping with multi-scalar multiplication technique we efficiently calculate scalar multiplication by s. Our proposed method can achieve 3 times or more than 3 times faster scalar multiplication compared to binary scalar multiplication, sliding-window and non-adjacent form method.

DOI： 10.1007/978-3-319-56549-1_19

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER INTERNATIONAL PUBLISHING AG  

Following the emergence of Kim and Barbulescu’s new number field sieve (exTNFS) algorithm at CRYPTO’16 [21] for solving discrete logarithm problem (DLP) over the finite field; pairing-based cryptography researchers are intrigued to find new parameters that confirm standard security levels against exTNFS. Recently, Barbulescu and Duquesne have suggested new parameters [3] for well-studied pairing-friendly curves i.e., Barreto-Naehrig (BN) [5], Barreto-Lynn-Scott (BLS-12) [4] and Kachisa-Schaefer-Scott (KSS-16) [19] curves at 128-bit security level (twist and sub-group attack secure). They have also concluded that in the context of Optimal-Ate pairing with their suggested parameters, BLS-12 and KSS-16 curves are more efficient choices than BN curves. Therefore, this paper selects the atypical and less studied pairing-friendly curve in literature, i.e., KSS-16 which offers quartic twist, while BN and BLS-12 curves have sextic twist. In this paper, the authors optimize Miller’s algorithm of Optimal-Ate pairing for the KSS-16 curve by deriving efficient sparse multiplication and implement them. Furthermore, this paper concentrates on the Miller’s algorithm to experimentally verify Barbulescu et al.’s estimation. The result shows that Miller’s algorithm time with the derived pseudo 8-sparse multiplication is most efficient for KSS-16 than other two curves. Therefore, this paper defends Barbulescu and Duquesne’s conclusion for 128-bit security.

DOI： 10.1007/978-3-319-71667-1_10

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掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/corr/corr1709.html#abs-1709-05163

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Binary extension field F28 is recently used for AES encryption and IoT (Internet of Things) security with PUF (Physical Unclonable Function). The calculations over tower field such as F(24)2 or F((22)2)2 become more efficient than that of over F28. This paper focuses on the efficient calculations over F(24)2.

DOI： 10.1109/ICCE-TW.2016.7520896

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper proposes a dynamic job scheduling method for reliable and high-performance volunteer computing. In volunteer computing, each job is replicated and allocated to multiple participants (workers) to remove incorrect results by a voting mechanism. Hence, the number of workers necessary to complete a job is an important factor for the system performance; however, this is not well-considered in the existing methods. The proposed method defines the expected probability of completion for each job based on the worker's secession probability. By allocating each job so that the expected probability is always greater than a specified value, the proposed method avoids excess job allocation, which leads to the higher performance. The performance of the proposed method is evaluated by computer simulation, under the two scenarios of workers having uniform and different processing speeds. It is found that the performance of the proposed method is higher than the existing method especially under the practical latter scenario.

DOI： 10.1109/ICISSEC.2015.7370964

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In elliptic curve cryptography (ECC), a scalar multiplication for rational point is the most time consuming operation. This paper proposes an efficient calculation for a scalar multiplication by applying Frobenious Mapping. Particularly, this paper deals with Barreto-Naehrig curve defined over extension field F-q(2), where q - p(6) and p is a large prime.

DOI： 10.1109/ICCE-TW.2016.7520894

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Barreto-Naehrig (BN) curve is a well studied pairing friendly curve of embedding degree 12, that uses arithmetic in F-p12. Therefore the arithmetic of F-p12 extension field is well studied. In this paper, we have proposed an efficient approach of arithmetic operation over the extension field of degree 18 by towering. F-p18 extension field arithmetic is considered to be the basis of implementing the next generation pairing based security protocols. We have proposed to use F-p element to construct irreducible binomial for building tower of extension field up to F-p6, where conventional approach uses the root of previous irreducible polynomial to create next irreducible polynomials. Therefore using F-p elements in irreducible binomial construction, reduces the number of multiplications in F-p to calculate inversion and multiplication over F-p18, which effects acceleration in total arithmetic operation over F-p18.

DOI： 10.1109/ICCITECHN.2016.7860209

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Pairing based cryptography is considered as the next generation of security for which it attracts many researcher to work on faster and efficient pairing to make it practical. Among the several challenges of efficient pairing; efficient scalar multiplication of rational point defined over extension field of degree k >= 12 is important. However, there exists isomorphic rational point group defined over relatively lower degree extension field. Exploiting such property, this paper has showed a mapping technique between isomorphic rational point groups in the context of Ate-based pairing with Kachisa-Schaefer-Scott (KSS) pairing friendly curve of embedding degree k = 18. In the case of KSS curve, there exists sub-field sextic twisted curve that includes sextic twisted isomorphic rational point group defined over F(p)3. This paper has showed the mapping procedure from certain F(p)18 rational point group to its sub-field isomorphic rational point group in F(p)3 and vice versa. This paper has also showed that scalar multiplication is about 20 times faster after applying the proposed mapping which in-turns resembles that the impact of this mapping will greatly enhance the pairing operation in KSS curve.

DOI： 10.1109/CANDAR.2016.38

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2016.html#KhandakerN16

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

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その他リンク： http://dblp.uni-trier.de/db/conf/isita/isita2016.html#conf/isita/ArshadNOIUMT16

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

DOI： 10.1109/CANDAR.2016.0109

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Pseudo random sequences play an important role in cryptography and network security system. This paper proposes a new approach for generation of pseudo random sequence over odd characteristic field. The sequence is generated by applying a primitive polynomial over odd characteristic field, trace function and mobius function. Then, some important properties of the newly generated sequence such as period, autocorrelation and cross-correlation have been studied in this work. The properties of the generated sequence are evaluated on various bit length of odd characteristics. Finally, the experimental results are compared with existing works which show the superiority of the proposed sequence over existing ones.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In our previous work, well balanced pseudo random signed binary sequence generated by using trace function and Legendre symbol has been researched. Our previous sequence generated by applying primitive polynomial over odd characteristic field F-p, trace function and Legendre symbol. The important features such as period, periodic autocorrelation, and cross-correlation have already been well discussed in our previous work. In this paper, the signed binary sequence is generated by utilizing one additional parameter A. Let p be an odd prime and F-p is an odd characteristic prime field and m be the degree of the primitive polynomial f(x). The procedure for generating sequence is as follows: primitive polynomial f (x) generates maximum length vector sequence, then trace function Tr (.) maps an element of extension field F(p)m to an element of prime field F-p, next a non-zero scalar A is an element of F-p is added to the trace value and finally Legendre symbol is used to map the scalars into signed binary sequence. In this paper, the authors have restricted the discussion on linear complexity and linear complexity profile properties of signed binary sequence based on some experimental results.

DOI： 10.1109/ICCITECHN.2016.7860207

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER INTERNATIONAL PUBLISHING AG  

In this paper we revisited the parallel implementations of LEA. By taking the advantages of both the light-weight features of LEA and the parallel computation abilities of ARM-NEON platforms, performance is significantly improved. We firstly optimized the implementations on ARM and NEON architectures. For ARM processor, barrel shifter instruction is used to hide the latencies for rotation operations. For NEON engine, the minimum number of NEON registers are assigned to the round key variables by performing the on-time round key loading from ARM registers. This approach reduces the required NEON registers for round key variables by three registers and the registers and temporal registers are used to retain four more plaintext for encryption operation. Furthermore, we finely transform the data into SIMD format by using transpose and swap instructions. The compact ARM and NEON implementations are combined together and computed in mixed processing way. This approach hides the latency of ARM computations into NEON overheads. Finally, multiple cores are fully exploited to perform the maximum throughputs on the target devices. The proposed implementations achieved the fastest LEA encryption within 3.2 cycle/byte for Cortex-A9 processors.

DOI： 10.1007/978-3-319-56549-1_27

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その他リンク： https://dblp.uni-trier.de/db/conf/wisa/wisa2016.html#SeoPHSBHZNZK16

掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Pseudo random sequences play an important role in cryptography and network security system. This paper proposes a new approach for generation of pseudo random sequence over odd characteristic field. The sequence is generated by applying a primitive polynomial over odd characteristic field, trace function and möbius function. Then, some important properties of the newly generated sequence such as period, autocorrelation and cross-correlation have been studied in this work. The properties of the generated sequence are evaluated on various bit length of odd characteristics. Finally, the experimental results are compared with existing works which show the superiority of the proposed sequence over existing ones.

DOI： 10.1109/IWCI.2016.7860341

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その他リンク： https://dblp.uni-trier.de/db/conf/iwci/iwci2016.html#AkhterN16

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Let p be an odd prime number as the characteristic of finite field, this paper introduces a pseudo random binary sequence generated by a primitive polynomial of degree 2 over F-p, trace function, and Legendre symbol. Then, its period and autocorrelation are introduced with a small example.

DOI： 10.1109/ICCE-TW.2016.7520895

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1007/978-3-662-48324-4_4

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その他リンク： https://dblp.uni-trier.de/db/conf/ches/ches2015.html#UenoHSNA15

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

It is shown that public key cryptosystems based on discrete logarithm probrem can be solved if the quantum computer and Shor's algorithm are realized. Thus a new cryptosystem called post-quantum cryptosystem so as not to be broken by quantum computer is needed. NTRU is proposed by Hoffstein et al. in 1998. It is one of post-quantum cryptosystem. It is based on problems on lattice for which there are no efficient algorithms to solve. In NTRU, using convolution polynomial ring as Zq[X]/(Xn-1). However, (X-1), that is a trivial factor of Xn-1 sometimes make problems. Thus we consider a variant using a quotient polynomial ring such as Zq[X]/(Xn + Xx-1 +...+X + 1) and CVMA: Cyclic Vector Multiplication Algorithm.

DOI： 10.1109/ICCE-TW.2015.7216956

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper presents the performance evaluations of GMP-based applications on Web-based Volunteer Computing (VC) systems. Web-based VC is expected to gather many volunteer participants (workers) by allowing workers to execute a computation program (job) on Web browsers. On the other hand, the job execution performance on workers degraded because jobs are executed on Web browsers. To reveal the actual performance of Web-based VC, we convert practical applications which use GMP, that is a multi-precision library for scientific computations, and evaluate its performance. The experimental results show that the performance degradation is negligibly small in some cases, e.g. a short bit-length of arguments. This paper also shows a potential for the performance improvement of Web-based VC by substituting GMP functions.

DOI： 10.1109/ICCE-TW.2015.7216970

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper addresses a job scheduling problem in Volunteer Computing (VC) systems, where some malicious participant may return incorrect results (sabotaging). Credibility-based job scheduling method, namely ENR-ECJ, is a promising approach to realize high-performance and sabotage-tolerant VC systems based on the credibility of each participant (worker). However, managing the credibility values in the management node may cause considerable performance degradation of whole the system. By implementing ENR-ECJ into a small scale VC system, this paper demonstrates the primacy of ENR-ECJ over existing methods and reveals its condition through the performance evaluation for various number of workers. The results show that ENR-EJC improves the overall performance about 10% when the access frequency of workers is less than 2 per second.

DOI： 10.1109/ICCE-TW.2015.7216948

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掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/iacr/iacr2015.html#Seo0NCK15a

掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/iacr/iacr2015.html#Seo0NCK15

掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Springer  

Binary field multiplication is the most fundamental building block of binary field Elliptic Curve Cryptography (ECC) and Galois/Counter Mode (GCM). Both bit-wise scanning and Look-Up Table (LUT) based methods are commonly used for binary field multiplication. In terms of Side Channel Attack (SCA), bit-wise scanning exploits insecure branch operations which leaks information in a form of timing and power consumption. On the other hands, LUT based method is regarded as a relatively secure approach because LUT access can be conducted in a regular and atomic form. This ensures a constant time solution as well. In this paper, we conduct the SCA on the LUT based binary field multiplication. The attack exploits the horizontal Correlation Power Analysis (CPA) on weights of LUT. We identify the operand with only a power trace of binary field multiplication. In order to prevent SCA, we also suggest a mask based binary field multiplication which ensures a regular and constant time solution without LUT and branch statements.

DOI： 10.1007/978-3-319-31875-2_14

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その他リンク： https://dblp.uni-trier.de/db/conf/wisa/wisa2015.html#SeoC0NPCK15

掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/iacr/iacr2015.html#SeoC0NPCK15

掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/iacr/iacr2015.html#UenoHSNA15

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Recently, binary sequences generated by chaotic maps have been widely studied. In particular, the logistic map is used as one of the chaotic map. However, if the logistic map is implemented by using finite precision computer arithmetic, rounding is required. In order to avoid rounding, Miyazaki, Araki, Uehara and Nogami proposed the logistic map over finite fields, and show some properties of sequences generated by the logistic map over finite fields. In this paper, we show some properties of periods of sequences generated by the logistic map over finite fields with control parameter four. In particular, we show conditions for parameters and initial values to have a long period, and asymptotic properties for periods by numerical experiments.

DOI： 10.1109/IWSDA.2015.7458394

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その他リンク： https://dblp.uni-trier.de/db/conf/iwsda/iwsda2015.html#TsuchiyaN15

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE Computer Society  

DOI： 10.1109/CANDAR.2015.53

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

An anonymous credential system allows a user to convince a service provider anonymously that he/she owns certified attributes. Previously, we proposed a paring-based anonymous credential system with constant size of proofs, where the combinations of logical AND and OR relations on user attributes can be proved as CNF formulas. However, this system has a problem of requiring large online computation time during authentication, which depends on the number of AND relations in the proved formula. In this paper, we propose an efficiency improvement of the computational overhead based on online/offline precomputation technique. In our improvement, all exponentiations that can be used for the accumulator and witness computations are executed in advance in the precomputation algorithm. Thus, exponentiations in the online accumulator and witness computations are excluded, and only multiplications are needed. We implemented the system using a fast pairing library, and measured the processing times, while changing the size of the proved CNF formula. The experimental result shows that the computational costs of the proof generation in the case of using lots of AND relations are greatly reduced than the previous system. Hence, it is practical for mobile users.

DOI： 10.1109/ICEEICT.2015.7307538

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

An anonymous credential system allows a user to convince a service provider anonymously that he/she owns certified attributes. Previously, an anonymous credential system was proposed to prove user's attributes to satisfy a monotone formula, i.e., a logic relation with any combination of AND/OR relations. However, this system has a problem of requiring large authentication time which depends on the number of attributes in the proved formula. In this paper, we propose methods to accelerate the authentication time by reducing the exponentiation costs for the calculations of accumulator and the witness which are used in the system. We implemented the accelerated system using a fast pairing library, and measured the authentication times, while changing the size of the proved relation.

DOI： 10.1109/ICCE-TW.2015.7216952

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Springer  

In this paper, we present high speed parallel multiplication and squaring algorithms for the Mersenne prime 2521 − 1. We exploit 1- level Karatsuba method in order to provide asymptotically faster integer multiplication and fast reduction algorithms. With these optimization techniques, ECDH on NIST’s (and SECG’s) curve P-521 requires 8.1/4M cycles on an ARM Cortex-A9/A15, respectively. As a comparison, on the same architecture, the latest OpenSSL 1.0.2d’s ECDH speed test for curve P-521 requires 23.8/18.7M cycles for ARM Cortex-A9/A15, respectively.

DOI： 10.1007/978-3-319-30840-1_11

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その他リンク： https://dblp.uni-trier.de/db/conf/icisc/icisc2015.html#Seo0NPCZK15

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Elliptic curve discrete logarithm problem (ECDLP) is the base of the security of elliptic curve cryptography (ECC). The verification of the security of ECC has been studied by solving an ECDLP. However, we need a large amount of computational resources for the verification. Then, this paper proposes a method gathering computational resources with Web-based Volunteer Computing (Web-based VC). This paper solves 70-bit ECDLP, and evaluates the computational performance of 2 types of the execution clients: Native Client (NaCl) and Portable NaCl (PNaCl). In the case of NaCl, 70-bit ECDLP was solved in 3086 seconds. On the other hand, in the case of PNaCl, 70-bit ECDLP was solved in 6583 seconds.

DOI： 10.1109/CANDAR.2015.46

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その他リンク： https://dblp.uni-trier.de/db/conf/ic-nc/candar2015.html#KajitaniNMA15

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

In our previous work, k-value pseudo random sequence generated by power residue symbol has been researched. The sequence is generated by applying a primitive polynomial over odd characteristics field, trace function, and power residue symbol. The sequence has some important features such as period, periodic autocorrelation, and linear complexity. In this paper, by applying an additional process to the previous procedure, an extended multi-value sequence is generated. Its features, such as the period, periodic autocorrelation, periodic crosscorrelation, and linear complexity are examined in this paper. According to the results, the new sequence also has some interesting features.

DOI： 10.1109/ICISSEC.2015.7371002

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Vector decomposition problem has been proposed on some supersingular curves whose embedding degree is 2 for example. In order to apply the problem as a trapdoor for some innovative cryptosystems, it is necessary to make pairing-related calculations more efficient. Our previous work has considered an approach for Tate pairing on a supersingular curve of embedding degree 2 over extension field of extension degree 2. It improved both Miller's algorithm and final exponentiation that was required for the Tate pairing. In detail, one multiplication in the calculation of Miller's loop was eliminated by using a twist mapping. This paper shows a more improved calculation of pairing with some experimental result for the efficiency discussion.

DOI： 10.1109/ICISSEC.2015.7370982

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掲載種別：研究論文（学術雑誌）  

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その他リンク： https://dblp.uni-trier.de/db/journals/corr/corr1510.html#TsuchiyaN15

掲載種別：研究論文（国際会議プロシーディングス）  

We analyzed equivalent current source of cryptographic circuits implemented on a field programmable gate array (FPGA). The equivalent current source represented internal switching current behaviors in the cryptographic circuits during an Advanced Encryption Standard (AES) operation. In this work, the internal current was analyzed for extracting leakage functions and correlation coefficients from scatter diagrams of the Hamming Distance (HD) of AES intermediate values and the current magnitudes. The obtained leakage functions were confirmed a well-known assumption on the HD power model that magnitude of switching current due to transition of register states is proportional to HD of the register. The internal current was also investigated in terms of correlation with the HD model. Correlation coefficients increased as transforming the external power trace in the internal current because two types of noise were reduced by the transform; constant noise and overlap effect of successive rounds. The noise reduction inferred that the use of the internal current source would provide more precise verification of countermeasures.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper investigated about introduction of the burst pulse injection method standardized for immunity tests to a cryptanalysis using faulty ciphertexts. We investigated the potential of the burst injection method to induce faulty ciphertexts experimentally. Firstly, the standard burst pulse was injected through the power cable to a cryptographic module implementing the Advanced Encryption Standard (AES) on a field programmable gate array (FPGA). As a result, it was confirmed that the burst pulse injection might cause clock glitches on the module. Secondly, the clock glitch was varied in magnitude and timing by use of two pulse generators and transmitted to the AES circuit to clarify what types of clock glitch induce critical faulty ciphertexts suited for recovering the crypto-key successfully. Results confirmed that the clock glitch had potential to induce faulty ciphertexts when it exceeded the threshold and produced a clock interval shorter than the critical path delay in the target round. The two experimental results suggested that burst pulse injection to cryptographic modules through their power cables is a possible scenario of fault analysis attacks.

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記述言語：日本語   出版者・発行元：一般社団法人エレクトロニクス実装学会  

バルク電流やバーストといった外乱注入により発生した暗号FPGAの誤動作に関して考察した。特に発生した誤動作の直接原因がクロックグリッチの場合について、まず、外乱によりFPGAのクロック配線にグリッチが重畳することを実験により検証した。次に、発生した誤動作をグリッチ付クロックをFPGAに直接与える構成において再現し、回路動作とグリッチの関係を検証した。以上の実験結果に基づき、外乱によりクロックグリッチが発生した場合の誤動作発生機構、および評価環境における誤動作発生確率を示した。

DOI： 10.11486/ejisso.28.0_63

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Pollard's rho method is well-known as an efficient method for solving discrete logarithm problem (DLP). This paper adopts the DLP on the so-denoted G(3) over Barreto-Naehrig curve, together with XTR group. Then, this paper shows this idea with the proposed algorithm, and the experimental computation time of solving the DLP is reduced by about 15%.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Recently, ordinary pairing-friendly elliptic curves whose embedding degree is 1 have been often focused on, for example some composite order pairing-based cryptographies do. In the case of non-symmetric pairings whose embedding degree is larger than 2, recent efficient pairing techniques such as Rate and Xate pairings adopt a certain special rational point group with an efficient isomorphic mapping and then accelerate pairing-related operations such as a pairing calculation and a scalar multiplication. Based on cubic, quartic, and sextic twists, this paper shows how to activate these efficient techniques together with point compression on pairing-friendly curves of embedding degree 1. © 2011 IEEE.

DOI： 10.1109/icc.2011.5962421

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その他リンク： https://dblp.uni-trier.de/db/conf/icc/icc2011.html#IzutaNM11

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

Recently, ordinary pairing-friendly elliptic curves whose embedding degree is 1 have been often focused on, for example some composite order pairing-based cryptographies do. In the case of non-symmetric pairings whose embedding degree is larger than 2, recent efficient pairing techniques such as Rate and Xate pairings adopt a certain special rational point group with an efficient isomorphic mapping and then accelerate pairing-related operations such as a pairing calculation and a scalar multiplication. Based on cubic, quartic, and sextic twists, this paper shows how to activate these efficient techniques together with point compression on pairing-friendly curves of embedding degree 1.

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掲載種別：研究論文（学術雑誌）  

Recently, ubiquitous Internet-access services have been provided by Internet service providers (ISPs) by deploying wireless local area networks (LANs) in public spaces including stations, hotels, and coffee shops. The IEEE802.1X protocol is usually used for user authentications to allow only authorized users to access services. Then, although user personal information of access locations, services, and operations can be easily collected by ISPs and thus, their strict management has been demanded, it becomes very difficult when multiple ISPs provide roaming services by their corporations. In this paper, we present an anonymous IEEE802.1X authentication system using a group signature scheme to allow user authentication without revealing their identities. Without user identities, ISPs cannot collect personal information. As an efficient revocable group signature scheme, we adopt the verifier-local revocation (VLR) type with some modifications for use of the fast pairing computation. We show the implementation of our proposal and evaluation results where the practicality of our system is confirmed for up to 1,000 revoked users.

DOI： 10.2197/ipsjjip.18.63

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：SPRINGER-VERLAG BERLIN  

In the case of Barreto-Naehrig pairing-friendly curves of embedding degree 12 of order r, recent efficient Ate pairings such as R-ate, optimal, and Xate pairings achieve Miller loop lengths of (1/4) left perpendicularlog(2) r right perpendicular]. On the other hand, the twisted Ate pairing requires (3/4) left perpendicularlog(2) r right perpendicular] loop iterations, and thus is usually slower than the recent efficient Ate pairings. This paper proposes an improved twisted Ate pairing using Frobenius maps and a small scalar multiplication. The proposal splits the Miller&apos;s algorithm calculation into several independent parts, for which multi-pairing techniques apply efficiently. The maximum number of loop iterations in Miller&apos;s algorithm for the proposed twisted Ate pairing is equal to the (1/4) left perpendicularlog(2) r right perpendicular] attained by the most efficient Ate pairings.

DOI： 10.1007/978-3-642-14423-3_4

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その他リンク： https://dblp.uni-trier.de/db/conf/icisc/icisc2009.html#SakemiTNM09

記述言語：英語   出版者・発行元：Information and Media Technologies 編集運営会議  

Recently, ubiquitous Internet-access services have been provided by Internet service providers (ISPs) by deploying wireless local area networks (LANs) in public spaces including stations, hotels, and coffee shops. The IEEE802.1X protocol is usually used for user authentications to allow only authorized users to access services. Then, although user personal information of access locations, services, and operations can be easily collected by ISPs and thus, their strict management has been demanded, it becomes very difficult when multiple ISPs provide roaming services by their corporations. In this paper, we present an anonymous IEEE802.1X authentication system using a group signature scheme to allow user authentication without revealing their identities. Without user identities, ISPs cannot collect personal information. As an efficient revocable group signature scheme, we adopt the verifier-local revocation (VLR) type with some modifications for use of the fast pairing computation. We show the implementation of our proposal and evaluation results where the practicality of our system is confirmed for up to 1, 000 revoked users.

DOI： 10.11185/imt.5.751

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

This paper shows two improvements of twisted te pairing with Barreto Naehrig curve so as to be efficiently carried out by dividing the calculation loops of Miller&apos;s algorithm based on divisor theorem. Then, this paper shows some experimental results from which it is shown that each improvements accelerate twisted- te pairing.

DOI： 10.1109/ICCIT.2009.203

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/ISCE.2009.5156956

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Institute of Electronics, Information and Communication, Engineers, IEICE  

This paper proposes an extension field named TypeII AOPF. This extension field adopts TypeII optimal normal basis, cyclic vector multiplication algorithm, and Itoh-Tsujii inversion algorithm. The calculation costs for a multiplication and inversion in this field is clearly given with the extension degree. For example, the arithmetic operations in TypeII AOPF Fp5 is about 20% faster than those in OFF Fp5, Then, since CVMA is suitable for parallel processing, we show that Typell AOPF is superior to AOPF as to parallel processing and then show that a multiplication in TypeII AOPF becomes about twice faster by parallelizing the CVMA computation in TypeII AOPF. Copyright © 2005 The Institute of Electronics, Information and Communication Engineers.

DOI： 10.1093/ietfec/e88-a.5.1200

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記述言語：日本語   出版者・発行元：一般社団法人映像情報メディア学会  

本稿では画像圧縮と切り取りに対して耐性をもつ電子透かし法を提案する.本手法では, まず透かしを挿入する対象画像にハール基底の離散ウェーブレット変換を施し, 多重解像度近似(MRA)を抽出する.そのMRAに対しPN系列を用いて周波数拡散を施し, その後1列ごとに1次元フーリエ変換を施す.得られたフーリエ係数を埋め込む透かし情報のピットに応じて増減させることにより情報を埋め込む.本手法は, PN系列を用いて周波数拡散しているため, 埋め込みに用いたPN系列を知らない第3者には解読・改竄はできないという特徴を有している.検出時には原画像のPN拡散を施したMRA成分と透かし情報の埋め込まれた画像のPN拡散MRAの差分を求め, 1次元離散フーリエ係数の変化分を算出している.このため切り取られた画像の一部分のデータからでも透かし情報の検出ができるという特徴をもっている.

DOI： 10.11485/itetr.25.83.0_49

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記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/030130100

記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/030130117

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IoT時代の到来に伴い,インターネットに接続する端末数が爆発的に増加すると予想されている.計算資源に乏しいIoT機器においても,十分な安全性を担保することが求められており,動画像の送受信における安全性が問題となっている.そこで本研究では,Raspberry Piで撮影した動画像をリアルタイムで暗号化して送信する際の性能評価を行った.検証の結果,1秒で30フレームの画像を処理可能であり,通信遅延を1秒に抑えた通信が可能である.
With the advent of the IoT era, it is expected that the number of devices connected to the Internet will explosively increase. Even with IoT devices that have limited computing resources, there is a need to ensure sufficient security, and video data transmission has become a serious issue. In this research we evaluated the performance of transmitting and encrypting the video data in real-time based on Raspberry Pi. And as a result, we can process 30 frames per second and have only a one-second delay.

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記述言語：日本語  

IoT時代の到来に伴い，インターネットに接続する端末数が爆発的に増加することが予想されている．IoT機器のような限られた計算資源下においても，暗号技術を用いた高信頼な情報通信を実現することが要求される．楕円曲線暗号は安全かつ効率的な公開鍵暗号であり，Curve25519は利便性の高い楕円曲線として注目を集める．一方で，サイドチャネル攻撃への耐性評価も重要となる．本稿では，FPGAに実装したCurve25519に対し，位数4の有理点を利用した単純電力解析による攻撃を行った．その結果，位数4の有理点を選択暗号文として用いることで，秘密鍵の特定が可能であることがわかった．
With the matter of secure communication between devices, and especially for IoT devices, more and more applications need trustful protocols to communicate using public key cryptography. Elliptic curve cryptography is nowadays a secure and efficient public key cryptography. One of the most recent and secure curves is Curve25519 and one of its failures is an attack on low-order elements during a Diffie-Hellman key exchange. This document shows that an attack using order 4 rational points is possible on an FPGA with simple power analysis, points out every IoT device using Curve255119 as a cryptographic method has a potential target to side-channel attacks.

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記述言語：英語   出版者・発行元：電子情報通信学会  

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記述言語：英語   出版者・発行元：電子情報通信学会  

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記述言語：英語   出版者・発行元：電子情報通信学会  

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記述言語：英語   出版者・発行元：電子情報通信学会  

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記述言語：日本語   出版者・発行元：一般社団法人 電気学会  

IoT・AI時代のセキュリティ

現代ICT社会は，インターネットを仲介して様々な情報がクラウドサーバなどに蓄積され，それをAIが解析して自動的に処理を行うという時代に入ってきている。例えば自

DOI： 10.1541/ieejjournal.139.313

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記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/029633293

記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/029631007

記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/029633004

記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/029633374

記述言語：日本語   出版者・発行元：電子情報通信学会  

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その他リンク： http://id.ndl.go.jp/bib/029631051

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記述言語：日本語   出版者・発行元：日本ソフトウェア科学会  

あらゆるデバイスがインターネットを介して繋がるIoT時代において，我々はそれらデバイスの利用により大きな利便性を享受できる一方，第三者からの攻撃を意識している利用者は決して多くはない．利用者がそういった意識を持つことはもちろん有意義なことであるが，それらデバイスを提供する側の人間は，より一層専門的な知識と意識付けが必要である．とりわけ，情報系の学部生など，エンジニアや研究者として第一線での活躍を目指す人材においてその必要性が顕著であり，「成長分野を支える情報技術人材の育成拠点の形成プログラム」であるenPiTでは，学部生に最先端の情報技術を学ぶ機会を提供し，社会の具体的な課題に対する解決力を身に付けた人材の育成を目指している．本稿では岡山大学で行われたenPiT-Security先進PBL演習Gの取り組みを紹介し，受講生の感想を踏まえて演習の有用性や改善の余地について述べる．

DOI： 10.11309/jssst.36.95

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記述言語：英語   出版者・発行元：電気学会  

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記述言語：英語   出版者・発行元：電気学会  

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記述言語：日本語   出版者・発行元：電子情報通信学会  

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DOI： 10.18178/ijiee.2018.8.1.685

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DOI： 10.18178/ijiee.2018.8.1.685

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記述言語：英語   出版者・発行元：電子情報通信学会  

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DOI： 10.24138/jcomss.v14i2.461

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DOI： 10.24138/jcomss.v14i1.446

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記述言語：英語   出版者・発行元：CROATIAN COMMUNICATIONS & INFORMATION SOC  

In cloud environment, profile matching is a key technique in applications such as health care and social networks. Ciphertext-Policy Attribute-Based Encryption (CP-ABE) is a suitable technique for data sharing in such environments. In this paper, we propose an asymmetric pairing based Hierarchical Multi-Authority CP-ABE (HM-CP-ABE) construction for profile matching. We utilize the fast Ate pairing to make the proposed HM-CP-ABE scheme efficient. The performance analysis of the proposed scheme shows improved efficiency in terms of computational costs for initialization, key generation and encryption using ELiPS library when compared with existing works.

DOI： 10.24138/jcomss.v14i2.461

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記述言語：英語   出版者・発行元：CROATIAN COMMUNICATIONS & INFORMATION SOC  

Wireless Body Area Networks (WBANs) play an important role in healthcare system by enabling medical experts to guide patients remotely. The unauthorized access of medical data from WBAN controller as well as the unreliable data communication may leads to risk for patients life. Currently, Chunqiang Hu et al., [1] proposed a data communication protocol by using Ciphertext-Policy Attribute-Based Encryption (CP-ABE) for a single file. The major limitation of Chunqiang Hu et al., [1] is that as the number of files increases, CP-ABE will suffer from parameters such as message size, energy consumption and computation cost. This paper proposes a more secure and efficient data communication scheme for WBANs by using an efficient File Hierarchy CP-ABE (FH-CP-ABE). The proposed scheme uses integrated access structure which is a combination of two or more access structures with hierarchical files encrypted. We evaluate the performance analysis of the proposed data communication protocol in terms of message size, energy consumption, computation cost and compared with Chunqiang Hu et al., [1].

DOI： 10.24138/jcomss.v14i1.446

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記述言語：英語  

DOI： 10.1587/transfun.E100.A.2720

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その他リンク： https://dblp.uni-trier.de/db/journals/ieicet/ieicet100a.html#TsuchiyaNU17

記述言語：日本語   出版者・発行元：電子情報通信学会  

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記述言語：英語  

本稿では，BLS曲線におけるPseudo 8-Sparse乗算を用いた効率的なMillerのアルゴリズムの実装方法について記す．近年新たな離散対数問題の解法アルゴリズム(exTNFS)が発表されたため，本稿ではこれに対応する最新のパラメータを用いて，BLS曲線とKSS曲線について効率的なOptimal-Ateペアリングの実装を行った．その結果，一回のペアリングにかかる時間はBN曲線よりもBLS曲線のほうが高速に実装することができた．
This paper shows an efficient Miller's algorithm implementation technique by applying pseudo 8-sparse multiplication over Barreto-Lynn-Scott (BLS12) curve of embedding degree 12. The recent development of exTNFS algorithm for solving discrete logarithm problem urges researchers to update parameter for pairing-based cryptography. Therefore, this papers applies the most recent parameters and also shows a comparative implementation of optimal-Ate pairing between BLS12 curve and Barreto-Naehrig (BN) curve. The result finds that pairing in BLS12 curve is faster than BN curve.

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担当区分：筆頭著者   記述言語：英語  

DOI： 10.1587/transfun.E100.A.1816

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その他リンク： https://dblp.uni-trier.de/db/journals/ieicet/ieicet100a.html#TsuchiyaN17

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DOI： 10.1587/transfun.E100.A.922

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DOI： 10.1587/transfun.E100.A.1838

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DOI： 10.6109/jicce.2017.15.2.97

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DOI： 10.1002/sec.1462

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記述言語：英語   出版者・発行元：ASSOC COMPUTING MACHINERY  

In this article, we present a hybrid method to improve the performance of the Montgomery reduction by taking advantage of the Karatsuba technique. We divide the Montgomery reduction into two sub-parts, including one for the conventional Montgomery reduction and the other one for Karatsuba-aided multiplication. This approach reduces the multiplication complexity of n-limb Montgomery reduction from theta(n(2) + n) to asymptotic complexity theta(7n(2)/8 + n). Our practical implementation results over an 8-bit microcontroller also show performance enhancements by 11%.

DOI： 10.1145/2890502

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DOI： 10.1145/2890502

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DOI： 10.1145/2890502

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担当区分：筆頭著者   記述言語：英語  

DOI： 10.1587/transinf.2015ICP0018

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その他リンク： https://dblp.uni-trier.de/db/journals/ieicet/ieicet99d.html#NogamiKIMN16

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DOI： 10.1587/transinf.2015PAP0027

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記述言語：英語   出版者・発行元：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

This paper addresses the problem of job scheduling in volunteer computing (VC) systems where each computation job is replicated and allocated to multiple participants (workers) to remove incorrect results by a votingmechanism. In the job scheduling of VC, the number of workers to complete a job is an important factor for the system performance; however, it cannot be fixed because some of the workers may secede in real VC. This is the problem that existing methods have not considered in the job scheduling. We propose a dynamic job scheduling method which considers the expected probability of completion (EPC) for each job based on the probability of worker's secession. The key idea of the proposed method is to allocate jobs so that EPC is always greater than a specified value (SPC). By setting SPC as a reasonable value, the proposed method enables to complete jobs without excess allocation, which leads to the higher performance of VC systems. We assume in this paper that worker's secession probability follows Weibull-distribution which is known to reflect more practical situation. We derive parameters for the distribution using actual trace data and compare the performance of the proposed and the previous method under the Weibull-distribution model, as well as the previous constant probability model. Simulation results show that the performance of the proposed method is up to 5 times higher than that of the existing method especially when the time for completing jobs is restricted, while keeping the error rate lower than a required value.

DOI： 10.1587/transinf.2015PAP0027

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その他リンク： https://dblp.uni-trier.de/db/journals/ieicet/ieicet98d.html#MiyakoshiYWFN15

記述言語：英語   出版者・発行元：電子情報通信学会  

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DOI： 10.1016/j.cose.2015.03.005

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記述言語：英語   出版者・発行元：ELSEVIER ADVANCED TECHNOLOGY  

Optimal Prime Fields (OPFs) are considered to be one of the best choices for lightweight elliptic curve cryptography implementations on resource-constraint embedded processors. In this paper, we revisit the efficient modular arithmetic over the special prime fields, and present improved implementations of modular multiplication and squaring for OPFs, called Optimal Prime Field Coarsely Integrated Operand Caching (OPF-CIOC) and Coarsely Integrated Sliding Block Doubling (OPF-CISBD) methods. The OPF-CIOC and OPF-CISBD methods follow the general ideas of (consecutive) operand caching and sliding block doubling techniques, respectively. The methods have been carefully optimized and redesigned for Montgomery multiplication and squaring in an integrated fashion. We then evaluate the practical performance of proposed methods on representative 8-bit AVR processor. Experimental results show that the proposed OPF-CIOC and OPF-CISBD methods outperform the previous best known results in ACNS'14 by a factor of 8% and 32%. Furthermore, our methods are implemented in a regular way which helps to reduce the leakage of side-channel information. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.cose.2015.03.005

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記述言語：日本語   出版者・発行元：一般社団法人電子情報通信学会  

現在主に利用されている公開鍵暗号の多くは,量子コンピューターの実現と,Shorのアルゴリズムによって破られることが示されている.この問題に対して,耐量子暗号と呼ばれる暗号の研究が行われている.NTRU暗号はHoffsteinらによって提案された耐量子暗号であり,円分多項式を用いるため,高速な演算が可能である.本研究では,これに対して円分多項式から自明な因数多項式を除いて与えられるAll One Polynomialと呼ばれる多項式を法とする多項式環All One Polynomial Ringを用いた方式を考える.この環上ではCVMAと呼ばれる乗算アルゴリズムが利用でき,NTRUと同様の理論で安全性に関する考察が行える.

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記述言語：日本語   出版者・発行元：一般社団法人電子情報通信学会  

吉田らは埋め込み次数2の超特異楕円曲線を用いたペアリング暗号におけるベクトル分解問題について詳細に考察を与えた.これをトラップドアとした暗号応用を考えると,ペアリングを高速化,効率化する必要があり,本稿では2次拡大体上の超特異楕円曲線を用いてTateペアリングの効率化を考える.Tateペアリングを構成するMillerのアルゴリズムと最終べきの両方に計算工夫を施した.超特異楕円曲線の性質を利用した計算の効率化,さらには曲線にツイスト写像を用いてMillerループ中の直線計算と接線計算の乗算を1回減らすことによって,どの程度ペアリングが効率化されたかを検討する.

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記述言語：英語  

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