On-Line Monitoring of Random Number Generators for Embedded Security

Many embedded security chips require a high-quality Random Number Generator (RNG). Unfortunately, hardware RNG randomness can vary in time due to implementation defects or certain kinds of attacks. To overcome this issue, this paper presents the implementation of a battery of statistical test for randomness. The battery is selected for its efficient implementation, making the area and power consumption insignificant. Performance and cost of the hardware implementation are given for FPGA and VLSI targets. Results show that statistical tests can easily be implemented in low-cost embedded security circuits and can enhance on-line monitoring of RNG randomness to prevent RNG failures.