(
Linear
Tape
Open) A family of open magnetic tape standards governed by HPE, IBM and Quantum that is licensed to third-party vendors. LTO is the only tape format in the 21st century with future plans. All other magnetic tapes are legacy storage formats, which may still be used in various companies. See
magnetic tape formats.
In 1998, two LTO formats were introduced that shared magnetic head and track layout, but the Ultrium cartridge was accepted, while the Accelis cassette never took off. An ambitious LTO roadmap is projecting an LTO-12 cartridge to have a native capacity of 144TB.
Built-in Cartridge Memory (CM)
LTO cartridges contain a memory (LTO CM), which is a non-volatile EEPROM chip that stores location data and usage. Like an RFID chip, it is read by radio waves. Starting with LTO-3, the CM chip contains algorithms that prevent tampering when LTO is used for read-only WORM storage. See
WORM and
EEPROM.
Partitioning
Starting with LTO-5, an index was added to the beginning of the tape that identifies the locations of the files. Partitioning, combined with the LTFS file system, makes LTO tape operate more like a disk (see
LTFS). See
WORM,
magnetic tape and
tape cartridge.
LTO-M (LTO-7 Cartridges for LTO-8)
LTO-7 cartridges can be initialized as LTO-M media for LTO-8 drives and store 9TB instead of 6TB. However, LTO-M cartridges cannot be read in LTO-7 drives.
An LTO (Ultrium) Cartridge
The tape is drawn out of the cartridge to a take-up reel inside the LTO drive.
Capacities
LTO Raw Tape EEPROM Hardware
Generation (TB) (KB) WORM Encrypt
LTO-14 576 | projected
LTO-13 288 | projected
LTO-12 144 | projected
LTO-11 72 | projected
LTO-10 36 | projected
LTO-9 2020 18 8 X X
LTO-8 2017 12 8 X X
LTO-7 2015 6 8 X X
LTO-6 2012 2.5 8 X X
LTO-5 2010 1.5 8 X X
(GB)
LTO-4 2007 800 8 X X
LTO-3 2005 400 4 X
LTO-2 2003 200 4
LTO-1 2000 100 4