Overview
ISO/IEC 13962:1995 specifies the DLT 2 data interchange format for 12.7 mm (0.5 in) wide, 112‑track magnetic tape cartridges. The standard defines the physical and magnetic characteristics of the cartridge and tape, the recording method and tape format, signal quality limits, error detection/correction mechanisms, and environmental and handling requirements. Used together with labelling standards (for example ISO 1001), it enables reliable interchangeability of cartridges between generating and receiving systems.
Key topics and technical requirements
- Physical tape and cartridge: materials (PET base film with ferromagnetic coating and conductive backcoat), tape length (355–365 m), tape width (12.649 mm ±0.010 mm), leader and cartridge mechanics.
- Magnetic recording characteristics: specified physical recording density (e.g., 1674 flux transitions per mm), bit‑cell/flux transition spacing, read signal amplitude, azimuth and channel skew limits, overwrite and peak‑shift requirements.
- Track and format layout: 112 physical tracks organized into logical pairs (logical tracks), calibration/guard/scratch/directory areas and detailed track locations and widths.
- Data format and error handling: byte and logical block formats; preamble, sync, data and control fields (CF1, CF2); CRC (Cyclic Redundancy Check) and ECC (Error‑Correcting Code) specifications and generation algorithms (annexes B, C).
- Conformance and interoperability: criteria for magnetictape cartridges, generating systems (writers) and receiving systems (readers) to claim conformance. Backward compatibility considerations noted with earlier DLT formats.
- Environment, handling and safety: test and operating environments (e.g., test conditioning 23 °C ±2 °C, 40–60% RH; operating 10–40 °C, 20–80% RH), storage/archival recommendations, transportation suggestions and flammability/safety requirements.
- Test and calibration: Master and Secondary Standard Reference Tapes, Standard Reference Amplitude/current, test recording current (1.1× standard), and procedures for measuring signal, roughness, friction, and durability.
Applications and who uses it
- Enterprise data backup and archival vendors who require a defined physical and logical tape format for long‑term storage and interchange.
- Tape drive and media manufacturers designing drives, cartridges and calibration tools to meet interchangeability and conformance.
- Data centers and IT operations teams standardizing backup media across multiple systems and vendors.
- Preservation and archives implementing long‑term storage media with specified environmental controls.
ISO/IEC 13962 is particularly relevant where vendor‑neutral interchangeability and predictable error handling (CRC/ECC) are critical.
Related standards
- ISO 1001 - File structure and labelling for magnetic tape interchange (referenced for labelling).
- ISO/IEC 13421 - earlier DLT format (12.7 mm, 48‑track) referenced for compatibility context.
Keywords: ISO/IEC 13962, DLT 2, 12.7 mm magnetic tape cartridge, 112‑track, tape format, data interchange, magnetic recording, CRC, ECC, tape archival, tape drive conformance.