Ideally, the generation of random numbers in CSPRNGs uses entropy obtained from a high-quality source, which might be a hardware random number generator or perhaps unpredictable system processes--though unexpected correlations have been found in several such ostensibly independent processes.
Ideally, the generation of random numbers in CSPRNGs uses entropy obtained from a high-quality source, generally the operating system's randomness API. However, unexpected correlations have been found in several such ostensibly independent processes.