Fast Digital TRNG Based on Metastable Ring Oscillator
- Cite this paper as:
- Vasyltsov I., Hambardzumyan E., Kim YS., Karpinskyy B. (2008) Fast Digital TRNG Based on Metastable Ring Oscillator. In: Oswald E., Rohatgi P. (eds) Cryptographic Hardware and Embedded Systems – CHES 2008. CHES 2008. Lecture Notes in Computer Science, vol 5154. Springer, Berlin, Heidelberg
In this paper, a new true random number generator (TRNG), based entirely on digital components is proposed. The design has been implemented using a fast random number generation method, which is dependent on a new type of ring oscillator with the ability to be set in metastable mode. Earlier methods of random number generation involved employment of jitter, whereas the proposed method leverages the metastability phenomenon in digital circuits and applies it to a ring oscillator. The new entropy employment method allows an increase in the TRNG throughput by significantly reducing the required entropy accumulating time. Samples obtained from simulation of TRNG design have been evaluated using AIS.31 and FIPS 140-1/2 statistical tests. The results of these tests have proven the high quality of generated data. Corners analysis of the TRNG design was also performed to estimate the robustness to technology process and environment variations. Investigated in FPGA technology, phase distribution highlighted the advantages of the proposed method over traditional architectures.