pen) A family of open magnetic tape standards developed by HP, IBM and Quantum (formerly the Certance subsidiary of Seagate) that is licensed to third-party vendors. As of 2019, LTO is the only thriving tape cartridge format.
LTO cartridges contain an LTO-CM (LTO cartridge memory), which is a non-volatile EEPROM chip that stores location data and usage. The tape is drawn out of the cartridge to a non-removable take-up reel inside the drive.
Although LTO was introduced with a native capacity of only 100GB, multi-terabyte tapes followed. Starting with LTO-3, write once-read many (WORM) support was added, and LTO-4 built in hardware encryption (see table below). See WORM
Ultrium Won Out
In 1998, two LTO formats were introduced: single-hub Ultrium and dual-hub Accelis. Sharing head, track layout and other features, the single-hub Ultrium was accepted, while Accelis never took off. For information, visit www.lto.org. See magnetic tape
An LTO (Ultrium) Cartridge
The single-hub Ultrium is the only LTO format, and LTO and Ultrium are synonymous.
Generation Native Hardware
(year) Capacity WORM Encryption
LTO-1 (2000) 100GB
LTO-2 (2003) 200GB
LTO-3 (2005) 400GB X
LTO-4 (2007) 800GB X X
LTO-5 (2010) 1.5TB X X
LTO-6 (2012) 2.5TB X X
LTO-7 (2015) 6.0TB X X
LTO-8 (2017) 12.0TB X X