Advanced Intelligent Tape (AIT) is a discontinued high-speed, high-capacity magnetic-tape data storage format developed and controlled by Sony. It was introduced in 1996 to use . It competed mainly against the DLT, LTO, DAT/DDS, and VXA formats. AIT uses 8 mm tape in a cassette similar to Video8. Super AIT (SAIT) is a higher-capacity variant using wider half-inch (1/2"; 12.7 mm) tape in a larger, single-spool cartridge. Both AIT and SAIT use the helical scan method of reading and writing to the tape.

Form factors

AIT technology was available in two form factors: AIT – 8 mm, dual-reel cartridge, similar to Sony's 8 mm videotape products and Exabyte's 8 mm data tape products. SAIT – 1/2" (12.7 mm), single-reel cartridge, similar to DLT and LTO.

In March 2010, Sony announced the discontinuation of the AIT product line and renewed collaboration with Hewlett-Packard on further development of the DDS tape format,

Compatibility One of the most compelling features of the AIT format is that many generations are both backwards and forwards compatible. This allows multiple generations of tape drives to both read and write to multiple generations of tape media.

AIT generations Generation AIT-E Turbo AIT-1 AIT-1 Turbo AIT-2 AIT-2 Turbo Release date 2004 1996 2004 1999 Native capacity (GB) 20 25, 35 40 36, 50 80 Max speed (MB/s) 6 3, 4 6 6 12 Encoding Trellis coding for partial response (TCPR) 4800 6400 Tape length (m) 98 170, 230 186 170, 230 186 Tape thickness (μm) 6.6 7.0, 5.3 6.6 7.0, 5.3 6.6

AIT-1 Original specification's data capacity up to 25 GB native and up to 65 GB compressed, with a data transfer speed of 3 MB/s. Extended length tape, introduced in 1999 gave additional capacity, 35 GB. Speed increased to 4 MB/s in 2001. Turbo variant, introduced in 2004, is 50% faster (6 MB/s) and holds 40 GB. A budget version, AIT-E Turbo, was also introduced in 2004 to compete with DDS. SATA version of AIT-1 Turbo available in 2006.

AIT-2 Doubled capacity and transfer speed WORM technology introduced Turbo variant has 100% higher capacity and is 100% faster (same speed as AIT-3) Turbo variant introduced R-MIC technology SATA version of AIT-2 Turbo available in 2006 Higher-capacity TAIT2-80N (Turbo) 80 GB native.

Generation AIT-3 AIT-3Ex AIT-4 AIT-5 AIT-6 Release date 2001 2006 2005 2006 cancelled Native capacity (GB) 100 150 200 400 800 Max speed (MB/s) 12 18 24 24 Encoding Extended TC-PRML Turbo-coded modulation Turbo-coded modulation Tape length (m) 230 246 246 Tape thickness (μm) 5.3 4.8 4.8 WORM-capable Yes Yes Yes Yes

AIT-3 Doubled capacity and transfer speed Ex variant has 50% higher capacity and is 50% faster

AIT-4 Doubled capacity and transfer speed New tape formulation, AME-2 Not compatible with previous generations

AIT-5 Available September 27, 2006 Announced July 2006, hardware and media expected "in the fall". Doubled capacity (via halved tracked pitch to 2.2 μm), maintained transfer speed. Backwards compatible with AIT-3, AIT-3Ex, AIT-4 New tape formulation, AME-3, which uses finer cobalt particles, resulting in SNR gain of 1 dB compared with AIT-4/AME-2. A switch to GMR head technology (Flux Guide GMR).

SAIT generations

Generation SAIT-1 SAIT-2 SAIT-3 SAIT-4 Release date 2003 2006 cancelled cancelled Native capacity (GB) 500 800 2000 4000 Max speed (MB/s) 30 45 120 240 Tape length (m) 600 640 Tape thickness (μm) 8.6

SAIT-1 Highest-capacity tape cartridge from 2003 to 2006. Displaced by DLT-S4 (800 GB). The AIT format was developed and is controlled by Sony.

SAIT-2 Released in 2006 by Sony, available only in libraries, 800 GB native and 45 MB/s sustained transfer rate.

Notes Data capacity and speed numbers above are for uncompressed data. Sony assumes a 2× or 2.6× compression factor in their marketing material. According to Sony, "All future products are based on technology projections."

Technical features

AME Advanced Metal Evaporated is a different formulation of tape media.Advanced Metal Evaporated (AME) is a magnetic tape technology that uses a thin vacuum-deposited metal film rather than the magnetic particles suspended in a binder used by conventional metal-particle tape media.

MIC Memory-in-Cassette is a 16–64 KB memory chip in the cartridge that keeps relevant information about the data on the tape to allow quicker access. The drive did not have to read the whole tape until it came across the file required like a file index.MIC (Memory-in-Cassette) is an integrated memory chip embedded in an AIT cartridge that stores metadata about the tape's contents. By maintaining information such as file locations and usage data, MIC enables faster access to stored data because the tape drive does not need to sequentially scan the entire tape to locate a file.

R-MIC Remote-Memory in Cassette. Like MIC, except it does not require physical contact.

WORM Write once read many functionality, useful for archive keeping.WORM (Write Once, Read Many) is a data storage feature that allows information to be written to a tape cartridge only once, preventing subsequent modification or deletion. This capability is commonly used for long-term archival storage and regulatory compliance.

References

External links ECMA 246 Specification of AIT-1. ECMA 291 Specification of AIT-1 w/ MIC. ECMA 292 Specification of AIT-2 w/ MIC. ECMA 329 Specification of AIT-3.