Editing Advanced Intelligent Tape

{{short description|Discontinued magnetic tape data storage format}}
{{more citations needed|date=August 2012}}
'''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 utilise Advanced Metal Evaporated (AME) technology.  It competed mainly against the [[Digital Linear Tape|DLT]], [[Linear Tape-Open|LTO]], [[Digital Data Storage|DAT/DDS]], and [[VXA]] formats.  AIT uses 8mm tape in a cassette similar to [[Video8]].  '''Super AIT''' ('''SAIT''') is a higher capacity variant using wider half inch (1/2") tape in a larger, single-spool cartridge.  Both AIT and SAIT use the [[helical scan]] method of reading and writing to the tape.

[[Image:AIT tapes.jpg|thumb|250px|AIT tapes.]]

== Form factors ==

AIT technology was available in two form factors.

* AIT – 8&nbsp;mm, dual reel cartridge, similar to Sony's 8&nbsp;mm videotape products and Exabyte's 8&nbsp;mm data tape products.
* SAIT – 1/2", single reel cartridge, similar to [[Digital Linear Tape|DLT]] and [[Linear Tape-Open|LTO]].

In March 2010, Sony announced the discontinuation of the AIT product line, and renewed collaboration with [[Hewlett-Packard]] on further development of the [[Digital Data Storage|DDS tape format]],<ref>{{cite web |url=http://synergybroadcast.com/blog/?p=2370 |title=Sony Kills AIT Line of Storage Products |website=synergybroadcast.com |url-status=dead |archive-url=https://web.archive.org/web/20100819020819/http://synergybroadcast.com/blog/?p=2370 |archive-date=2010-08-19}} </ref>

== 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 ==
{| class="wikitable" style="float:right; margin-left: 1em;"
! 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)
|
|-
| RPM
|
| 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&nbsp;GB native and up to 65 GB compressed, with a data transfer speed of 3&nbsp;MB/s.
* Extended length tape, introduced in 1999 gave additional capacity, 35&nbsp;GB.
* Speed increased to 4&nbsp;MB/s in 2001.
* Turbo variant, introduced in 2004, is 50% faster (6&nbsp;MB/s) and holds 40&nbsp;GB.
* A budget version, AIT-E Turbo, was also introduced in 2004 to compete with [[Digital Data Storage|DDS]].
* SATA version of AIT-1 Turbo available in 2006.

=== AIT-2 ===
* Doubled capacity and transfer speed
* [[Write Once Read Many|WORM]] technology introduced
* Turbo variant is 100% higher capacity, 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) 80Gb native.

{| class="wikitable" style="float:right; margin-left: 1em;"
! 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 is 50% higher capacity, 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<ref>{{cite press release |url=http://www.sony-europe.com/res/attachment/file/79/1159199085479.pdf |title=Sony announces availability of its fifth generation tape drive and media in celebrating 10 years of AIT |publisher=Sony |format=PDF |date=September 27, 2006 |accessdate=2007-10-15| archiveurl= https://web.archive.org/web/20070928123755/http://www.sony-europe.com/res/attachment/file/79/1159199085479.pdf| archivedate= 28 September 2007 | url-status= live}}</ref>
* 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&nbsp;dB compared with AIT-4/AME-2.
* A switch to [[Giant magnetoresistance|GMR head]] technology (Flux Guide GMR).

== SAIT generations ==
[[File:Supertape data storage capacities.svg|thumb|500px|Comparison of "supertape" capacities, including SAIT.]]
{| class="wikitable" style="margin-left: 1em;"
! 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&nbsp;GB).
The AIT format was developed and is controlled by Sony.

=== SAIT-2 ===
Released in 2006 by Sony, available only in libraries, 800&nbsp;GB native and 45&nbsp;MB/s sustained transfer rate.<ref name="sonybiz">{{cite web
  | title = SAIT2-800
  | publisher = Sony
  | url = http://www.sonybiz.net/biz/view/ShowProduct.action?product=SAIT2-800&site=biz_en_EU&pageType=OverviewFeatures&category=STO+S-AIT
  | format =
  | doi =
  | accessdate =  2007-01-30}}</ref>

== Notes ==
* Data Capacity and Speed figures above are for ''uncompressed'' data.  Sony assumes a 2x or 2.6x 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.

=== MIC ===
Memory-in-Cassette
is a 16-64KB 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.

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

=== WORM ===
[[Write Once Read Many]] functionality, useful for [[data|archive]] keeping.

==References==
<references/>

==External links==
* [http://www.ecma-international.org/publications/standards/Ecma-246.htm ECMA 246] Specification of AIT-1. [http://www.ecma-international.org/publications/files/ecma-st/ECMA-246.pdf]
* [http://www.ecma-international.org/publications/standards/Ecma-291.htm ECMA 291] Specification of AIT-1 w/ MIC. [http://www.ecma-international.org/publications/files/ecma-st/ECMA-291.pdf]
* [http://www.ecma-international.org/publications/standards/Ecma-292.htm ECMA 292] Specification of AIT-2 w/ MIC. [http://www.ecma-international.org/publications/files/ecma-st/ECMA-292.pdf]
* [http://www.ecma-international.org/publications/standards/Ecma-329.htm ECMA 329] Specification of AIT-3. [http://www.ecma-international.org/publications/files/ecma-st/ECMA-329.pdf]

{{Magnetic tape data formats}}
{{Ecma International Standards}}

[[Category:Computer storage tape media]]
[[Category:Ecma standards]]