CRYPTOGRAPHIC KEY PRODUCTION FROM A PHYSICAL UNCLONABLE FUNCTION

摘要

An electronic cryptographic device (100) arranged to determine a cryptographic key. The cryptographic device has a physically unclonable function (PUF) (110), a debiasing unit (120) and a key reconstruction unit (150). The PUF is arranged to produce a first noisy bit string (112) during an enrollment phase and a second noisy bit string (114) during a reconstruction phase. The debiasing unit (120) is arranged to determine debiasing data (142) from the first noisy bit string during the enrollment phase. The debiasing data marks bits in the first noisy bit string as retained or discarded. The key reconstruction unit (150) is arranged to determine the cryptographic key from bits in the second noisy bit string marked as retained by the debiasing data, the cryptographic key being independent from bits in the second noisy bit string marked as discarded by the debiasing data.