Editing Digital Linear Tape (section)

==Technology==
DLT uses [[Magnetic tape data storage#Linear|linear serpentine]] recording with multiple tracks on half-inch (12.7&nbsp;mm) wide tape. The [[Data cartridge (tape)|cartridges]] contain a single [[reel]] and the [[Magnetic tape|tape]] is pulled out of the cartridge by means of a leader tape attached to the take-up reel inside the drive. The drive leader tape is buckled to the cartridge leader during the load process. Tape speed and tension are controlled electronically via the reel motors; there is no [[Capstan (tape recorder) |capstan]]. The tape is guided by 4 to 6 rollers that touch only the back side of the tape. Tape material is [[metal particle tape]] (MP/AMP).

SDLT adds an [[Visual Servoing|optical servo]] system that reads servo patterns on the back of the tape to keep the data tracks on the front of the tape correctly aligned with the read/write heads. This is important for newer tape media, which have very thin, dense data tracks; 256, 384 and 768 data tracks on a {{convert |1/2|in|mm| adj=mid|-wide}} tape are available. 

DLT7000 and 8000 tilt the head forward and backward to reduce crosstalk between adjacent tracks through [[azimuth]]; this is called [[Symmetric Phase Recording]].

All (S)DLT drives support hardware [[data compression]]. The often-used compression factor of 2:1 is optimistic and generally only achievable for text data; a more realistic factor for a file system is 1.3:1 to 1.5:1, although drive compression applied to pre-compressed data can actually make the written data larger than having compression turned off in the tape drive.

Media are guaranteed for 30 years of [[data retention]] under specified environmental conditions; they are easily damaged by mishandling (dropping or improper packaging during shipment.)

Manufacturers of cartridges for the DLT/SDLT market are [[Fujifilm]], Hitachi/[[Maxell]] and [[Imation]]. VStape is made by [[Sony]]. All other companies/brands (even Quantum) are contractors and/or resellers of these companies.

A new naming convention took effect in 2005, calling the performance line DLT-S and the value line DLT-V.

DLT includes [[Write Once Read Many]] (WORM) capability.<ref>{{Citation | url = http://www.quantum.com/Products/TapeDrives/DLT/DLTSageWORM/ | title = DLTSage WORM functionality is available at no additional charge | publisher = Quantum}}.</ref>

In February 2007, Quantum stopped developing the next generations of DLT drives (S5 and V5) after insufficient market acceptance of the S4 and V4 drives, shifting its drive strategy to [[Linear Tape-Open|LTO]].