Advanced Intelligent Tape (AIT) data cartridges were developed in 1996 by Sony. AIT data cartridges record data onto an 8mm media using the helical scan recording method. Another feature is the Memory In Cassette (MIC) chip which is used to store information about the data recorded on the tape.
The first AIT tape data cartridge had a native storage capacity of 25GB which was further developed with the 5th generation released in 2007 capable of storing 400GB of uncompressed data. The first Super AIT (SAIT) was released in 2003 with a native capacity of 500GB with the 2nd generation released in 2006 was capable of holding 800GB of uncompressed data, but only available in tape libraries. Sony officially announced the discontinuation of the AIT and SAIT range in 2010. Despite being obsolete some are still in use, mostly for restoring archive data, some of which have required tape data recovery.
Forerunner to AIT
The predecessor to AIT was the Exabyte tape data cartridge, also using 8mm media using the helical scan recording method. The Exabyte tapes were developed using the same technology as 8mm video recorders, engineered to record digital data. Exabyte Mammoth tapes a higher capacity format was introduced by the Exabyte Corporation, but struggled to compete with AIT, despite the release of the Mammoth 2 data cartridge in 1999.
Advanced Tape Technology
All AIT and Super AIT tape data cartridges use media created using the Advanced Metal Evaporation (AME) technique, allowing both higher density and more reliable data recording, when compared to the traditional Metal Particle tapes using in the original Exabyte cartridges.
The MIC chip contains data only for use by the tape drive, with no area for user data as seen in in the LTO memory chip. There is the possibility to create up to 12 partitions on an AIT data cartridge, although in practise most data cartridges only contain a single data area.
AIT and SAIT Data Recovery
The three most common reasons an AIT data cartridge will require tape data recovery is physical failure, logical data issues or user errors. Physical problems include tape media flaws, unreadable media, snapped tape and de-spooled media. Logical issues are related to a corruption of the tape backup or other restore failures.
A user error such as reinitialising the tape will usually result in some loss of data. A backup format which stores a large area of metadata at the front of the tape may however sometimes allow all files to be recovered. Should you overwrite a previous backup this will lead to some loss of data, the extent of which is depends on the amount data written during the original and subsequent backup.