Non-physical true random number generator

A non-physical true random number generator (NPTRNG), also known as a non-physical nondeterministic random bit generator, is a generator of unpredictable random numbers without the use of a dedicated hardware entropy source. An NPTRNG uses a non-physical noise source that obtains entropy from system data, such as outputs of application programming interface functions, residual information in random access memory, system time, or human input, in the expectation that that data may contain elements that are truly random or at least not known to or controllable by an adversary. A typical NPTRNG is implemented as software running on a general-purpose computer. NPTRNGs are found in the kernels of popular operating systems that are expected to run on any generic CPU without requiring specialised hardware.