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A version of the SCAP specification designated by a revision number in the format nn.nn.nn, where the first nn is the major revision number, the second nn number is the minor revision number, and the final nn number is the refinement number. A specific SCAP revision will populate all three fields, even if that means using zeros to show no minor revision or refinement number has been used to date. A leading zero will be used to pad single-digit revision or refinement numbers.
NISTIR 7511 Rev. 4