Design and implementation of a novel cryptographically secure pseudorandom number generator
To address the challenge of simultaneously achieving security, statistical quality, and hardware efficiency in pseudorandom number generators (PRNGs) for lightweight cryptographic applications, this paper proposes a novel cryptographically secure PRNG (CSPRNG). The core innovation lies in the first integration of a lightweight modular exponentiation chain—providing strong mathematical hardness—with a customized Feistel-like nonlinear structure that employs S-boxes, bit-level diffusion, and permutation for efficient non-linear confusion. Implemented on FPGA, the design achieves a throughput of 1.2 Gbps while reducing area overhead by 37% compared to state-of-the-art lightweight CSPRNGs. It passes all statistical tests in both NIST SP 800-22 and Dieharder suites on a 2⁴⁰-bit output sequence. The proposed CSPRNG thus delivers provable cryptographic security, excellent statistical randomness, and high hardware efficiency with good portability across constrained platforms.