Overview
ISO/IEC 11694-5:2014 specifies the data format for optical memory cards that use the linear recording method, enabling compatibility and interchange between systems. Part 5 defines the logical conventions - directory layout, tag-based identification and TLV (Tag-Length-Value) streams - that allow different card writers and readers to find, interpret and share data on the card’s public zone. It complements ISO/IEC 11694-4 (logical data structures) and the other parts of ISO/IEC 11694 that address physical and optical characteristics.
Key topics and technical requirements
- Tag-based identification: Data items are identified by a unique 16-bit tag; tags are assigned and documented by a tag issuing body (it is proposed that HID Global act as the tag issuing body). Tags enable universal interpretation of stored items.
- TLV data streams: Multiple data items can be stored in a TLV (Tag, Length, Value) stream within a single data file; a tag value of zero terminates the stream.
- Directory structure: The standard defines the starting location and format of the directory used to map data items to locations on the card; writers select data locations and then write directory entries so readers can locate files.
- Data files and layouts: A data file may contain a single data item or a TLV stream. A data item has a defined meaning and layout; tag documents describe both.
- Little-endian numeric format: All multi‑byte numbers are written in little-endian order on the media.
- Public vs private zones: Cards may include a public zone (accessible to all drives) and a private zone (restricted); ISO/IEC 11694-5 governs public-zone data formatting.
- Defined tag ranges: The standard defines tag ranges for categories (examples):
- 1000 - ICAO MRZ data
- 1001–1999 - Demographic text
- 2000–2999 - Encoded face
- 3000–3999 - Encoded finger
- 6000–6999 - Displayed portrait
(Readers can search ranges relevant to their application.)
- Interoperability rules: A card is not fully compliant unless each public-zone data item has a published tag document describing its layout and meaning.
Practical applications and who uses this standard
ISO/IEC 11694-5:2014 is used by:
- Card manufacturers and optical memory card vendors
- System integrators and OEMs building card readers/writers
- Government identity programs (eIDs, passports, national ID)
- Access control and secure credentialing systems
- Biometric system implementers (face, fingerprint, iris templates)
- Software developers and middleware that parse TLV streams and directory entries
Benefits include reliable data interchange, standardized storage of images and biometrics, and simplified reader implementations.
Related standards
- ISO/IEC 11694-1 through -6 (Physical characteristics, dimensions, optical properties, logical structures, data format - this part, biometrics)
- ISO/IEC 11694-4 (Logical data structures) - normative reference
Keywords: ISO/IEC 11694-5:2014, optical memory cards, linear recording method, data format, TLV, tags, directory structure, little-endian, optical stripe, tag issuing body.
Open preview (PDF)Identification cards — Optical memory cards — Linear recording method — Part 5: Data format for information interchange for applications using ISO/IEC 11694-4