Thermal noise is an unpredictable electrical fluctuation from thermal motion in a resistor, usable as a physical source of randomness. section 2.2.1
Using thermal noise in a true random number generator requires:
- Estimating the entropy and generation rate from the physical source rather than predicting the actual output bits. section 2.2.1
- Adding health checks that can shut down the generator when operation becomes faulty. section 2.2.1
- Protecting the generator against attackers who can physically tamper with or influence its output. section 2.2.1
Resistor as a randomness source
Sampling thermal noise from a resistor provides unpredictable values, but the usable output rate depends on how quickly the underlying physical phenomenon can be sampled. section 2.2.1
