Sujoy Sinha Roy

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In this paper we propose an efficient and compact processor for a ring-LWE based encryption scheme. We present three optimizations for the Number Theoretic Transform (NTT) used for polynomial multiplication: we avoid preprocessing in the negative wrapped convolution by merging it with the main algorithm, we reduce the fixed computation cost of the twiddle(More)
Present-day public-key cryptosystems such as RSA and Elliptic Curve Cryptography (ECC) will become insecure when quantum computers become a reality. This paper presents the new state of the art in efficient software implementations of a post-quantum secure public-key encryption scheme based on the ring-LWE problem. We use a 32-bit ARM Cortex-M4F(More)
In this paper we present an FPGA implementation of a highspeed elliptic curve scalar multiplier for binary finite fields. High speeds are achieved by boosting the operating clock frequency while at the same time reducing the number of clock cycles required to do a scalar multiplication. To increase clock frequency, the design uses optimized implementations(More)
Lattice-based public key cryptography often requires sampling from discrete Gaussian distributions. In this paper we present an efficient hardware implementation of a discrete Gaussian sampler with high precision and large tail-bound based on the Knuth-Yao algorithm. The Knuth-Yao algorithm is chosen since it requires a minimal number of random bits and is(More)
Public-key cryptography based on the “ring-variant” of the Learning with Errors (ring-LWE) problem is both efficient and believed to remain secure in a post-quantum world. In this paper, we introduce a carefully-optimized implementation of a ring-LWE encryption scheme for 8-bit AVR processors like the ATxmega128. Our research contributions include several(More)
Polynomial multiplication is the basic and most computationally intensive operation in ring-Learning With Errors (ring-LWE) encryption and “Somewhat” Homomorphic Encryption (SHE) cryptosystems. In this paper, the Fast Fourier Transform (FFT) with a linearithmic complexity of O(n logn), is exploited in the design of a high-speed polynomial multiplier. A(More)
We present a hardware architecture for all building blocks required in polynomial ring based fully homomorphic schemes and use it to instantiate the somewhat homomorphic encryption scheme YASHE. Our implementation is the first FPGA implementation that is designed for evaluating functions on homomorphically encrypted data (up to a certain multiplicative(More)
We propose a lightweight coprocessor for 16-bit microcontrollers that implements high security elliptic curve cryptography. It uses a 283-bit Koblitz curve and offers 140-bit security. Koblitz curves offer fast point multiplications if the scalars are given as specific τ -adic expansions, which results in a need for conversions between integers and τ -adic(More)