A New TRNG Based on Coherent Sampling With Self-Timed Rings

Random numbers play a key role in applications such as industrial simulations, laboratory experimentation, computer games, and engineering problem solving. The design of new true random generators (TRNGs) has attracted the attention of the research community for many years. Designs with little hardware requirements and high throughput are demanded by new and powerful applications. In this paper, we introduce the design of a novel TRNG based on the coherent sampling (CS) phenomenon. Contrary to most designs based on this phenomenon, ours uses self-timed rings (STRs) instead of the commonly employed ring oscillators (ROs). Our design has two key advantages over existing proposals based on CS. It does not depend on the FPGA vendor used and does not need manual placement and routing in the manufacturing process, resulting in a highly portable generator. Our experiments show that the TRNG offers a very high throughput with a moderate cost in hardware. The results obtained with ENT, DIEHARD, and National Institute of Standards and Technology (NIST) statistical test suites evidence that the output bitstream behaves as a truly random variable.