Abstract: Techniques are described for using unique features of a storage medium for authentication of data as originating from the storage medium, and also for installing software and data to a storage medium in a way which inhibits unauthorized copying of the software and data to another storage medium. Cryptoprocessing keys are created using unique features of the storage medium such as location information related to storage of selected elements of a software installation on the storage medium, or alternatively defective block information relating to the storage medium. The cryptoprocessing keys are used to encrypt data for transmission to a remote server. The remote server uses the cryptoprocessing keys to decrypt the data and authenticates the data as having been encrypted with the correct keys. In order to control operation of software on a storage medium, location information unique to the storage medium is employed to create links between software modules comprising the software.

Abstract: Magnetic media containing data and method for data verification are disclosed. The data verification method utilizes the relative position of specific features of magnetic media signals, such as, peak zero crossings, the ratio of preselected amplitudes, the locii of preselected points along the signal, the RMS value of the waveform and the like. In the preferred embodiment, the ratio of the separation of adjacent pulses in the signal is employed. The deviation of the precise location of the placement of the peak points in the signal waveform is referred to as "jitter". This "jitter" is enhanced to provide a pattern of "jitter" or a magnetic "signature" that is random, nonreproducible and that can be used to positively identify a particular specimen of magnetic media and the associated data. The magnetic jitter pattern or security signature can be separate from or an integral part of the data recorded on the magnetic media.