Part 3: Transmittal format binary encoding
Part 3: Transmittal format binary encoding
This part of ISO/IEC 18023 defines a binary encoding technique that allows encoding DRM objects specified in Part 1 of ISO/IEC 18023 according to the abstract syntax specified in Part 2 of ISO/IEC 18023. The name of this binary encoding is SEDRIS Transmittal Format (STF). The STF was designed to be as efficient as possible for general purpose use of the API.
http://www.iso.ch/iso/en/ittf/PubliclyAvailableStandards/ISO_IEC_18023-3_Ed1.html