Improvements in and relating to data protection

摘要

A data storage tape 4 has an associated memory device 3 in which is stored a number of signatures 12 each representative of and associated with a particular data set recorded on the storage medium. By comparing the signatures against either signatures created during reading of the data sets back from the tape or against reference information held on a secure database any tampering or alteration of the data on the storage medium can be detected.