Entropy source for random number generation

Abstract

In a device having a data channel, in which random numbers are needed, such as a data storage device that uses random numbers to generate keys for cryptographic applications, random numbers are generated by a deterministic random bit generator seeded by bits derived from noise on the channel itself. The bits may be extracted from the least significant bits of the data signal after it is digitized, because those bits correspond to the noise in the signal. The extraction may occur immediately after digitization, or after subsequent filtering. A data signal emulator may be provided to simulate a data signal if a seed is required at a time when there is no data activity on the channel. The extracted bits may be post-processed to remove bias before the seed is provided to the deterministic random bit generator.

Dependencies are inferred from the claim text.