High-Speed NTT-based Polynomial Multiplication Accelerator for CRYSTALS-Kyber Post-Quantum Cryptography

This paper demonstrates an architecture for accelerating the polynomial multiplication using number theoretic transform (NTT). Kyber is one of the finalists in the third round of the NIST post-quantum cryptography standardization process. Simultaneously, the performance of NTT execution is its main challenge, requiring large memory and complex memory access pattern. In this paper, an efficient NTT architecture is presented to improve the respective computation time. We propose several optimization strategies for efficiency improvement targeting different performance requirements for various applications. Our NTT architecture, including four butterfly cores, occupies only 798 LUTs and 715 FFs on a small Artix-7 FPGA, showing more than 44% improvement compared to the best previous work. We also implement a coprocessor architecture for Kyber KEM benefiting from our high-speed NTT core to accomplish three phases of the key exchange in 9, 12, and 19 \mus, respectively, operating at 200 MHz

Progress in Cryptology – AFRICACRYPT 2019: 11th International Conference on Cryptology in Africa, Rabat, Morocco, July 9–11, 2019, Proceedings

International audienceThis book constitutes the refereed proceedings of the 11th International Conference on the Theory and Application of Cryptographic Techniques in Africa, AFRICACRYPT 2019, held in Rabat, Morocco, in July 2019. The 22 papers presented in this book were carefully reviewed and selected from 53 submissions. The papers are organized in topical sections on protocols; post-quantum cryptography; zero-knowledge; lattice based cryptography; new schemes and analysis; block ciphers; side-channel attacks and countermeasures; signatures. AFRICACRYPT is a major scientific event that seeks to advance and promote the field of cryptology on the African continent. The conference has systematically drawn some excellent contributions to the field. The conference has always been organized in cooperation with the International Association for Cryptologic Research (IACR)

Blockchain Agency Theory

Longstanding assumptions underlying strategic alliances, such as agency theory, are actively being revoked by dynamics in the new economy. The mechanism of inter-firm cooperation is increasingly being altered by radical developments in blockchains and artificial intelligence among other technologies. To capture and address this shift, this review takes a problematisation approach and focuses wholly on the pertinence of agency theory. First, it begins by acknowledging the established corpus in the area before, second, appraising the seven long-held assumptions in the principal-agent relationship encompassing (1) self-interest, (2) conflicting goals, (3) bounded rationality, (4) information asymmetry, (5) pre-eminence of efficiency, (6) risk aversion and (7) information as a commodity. Third, to add a fresh perspective, the review proceeds to proffer seven assumptions to advance a novel ‘Blockchain Agency Theory’ that would better describe new attributes and relaxed agency behaviour in blockchain alliances. These counter assumptions are (1) common interests, (2) congruent goals, (3) unbounded rationality, (4) information symmetry, (5) smart contracts, (6) mean risk and (7) information availability. In the fourth part, the prior audience of principals and agents is appraised and this culminates into, fifth, a consideration of a new audience of blockchain agency in algocratic environments. Altogether, the seven new assumptions extend and provoke new agency thinking among scholars and blockchain practitioners alike

Constant time algorithms for ROLLO-I-128

In this work, we propose different techniques that can be used to implement the ROLLO, and partially RQC, family of algorithms in a standalone, efficient and constant time library. For simplicity, we focus our attention on one specific instance of this family, ROLLO-I-128. For each of these techniques, we present explicit code (with intrinsics when required), or pseudo-code and performance measures to show their impact. More precisely, we use a combination of original and known results and describe procedures for Gaussian reduction of binary matrices, generation of vectors of given rank, multiplication with lazy reduction and inversion of polynomials in a composite Galois field. We also carry out a global performance analysis to show the impact of these improvements on ROLLO-I-128. Through the SUPERCOP framework, we compare it to other 128-bit secure KEMs in the NIST competition. To our knowledge, this is the first optimized full constant time implementation of ROLLO-I-128