Tape backup
Also known as: LTO tape, tape storage, magnetic tape backup, LTO backup
Tape backup stores copies of data on magnetic tape cartridges, most commonly the LTO (Linear Tape-Open) format.
Tape offers very low cost per terabyte, long shelf life of decades when stored properly, and the ability to be physically disconnected and stored offsite, creating an 'air gap' ransomware can't reach. While tape seems old-fashioned, large organizations and cloud providers still rely on it for archives, though restoring from tape is slower than from disk or cloud.
Tape backup, explained at three levels
At home
Tape backup is like copying important papers into a sturdy box and storing it in a bank vault. Getting a document back takes a trip and some searching, but the box is cheap, lasts for decades and nobody can tamper with it from home. Tape works the same way: data is written to a cartridge, which is then removed and stored away from computers.
At work
Tape backup copies data onto magnetic tape cartridges, mostly in the LTO format, which hold tens of terabytes each. Once written, cartridges can be ejected and stored offsite, completely disconnected from the network. Businesses care because tape is very cheap per terabyte, lasts for decades and creates an offline copy that ransomware cannot reach, though restoring from it is slower than from disk.
At home
Tape stores data on a long ribbon of magnetic film wound inside a cartridge. A drive pulls the tape past a read and write head, recording data in many parallel tracks as it moves back and forth. Because the tape must wind to the right spot, finding one file is slow, but writing or reading large amounts in sequence is fast. Once written, a cartridge can be ejected and stored offline, where no hacker or ransomware can reach it.
At work
LTO is the dominant format, and recent generations, LTO-9 and LTO-10, store tens of terabytes per cartridge before compression. LTO supports hardware AES encryption and write-once, read-many cartridges for compliance. Earlier drives read one or two generations back, but LTO-10 dropped backward compatibility, so plan migrations as generations advance. Backup software catalogues what is on each tape, and tape libraries use robots to load cartridges automatically. Tapes are rotated offsite on a schedule.
At home
Old family videos on VHS or camcorder tapes use the same basic magnetic idea, but consumer tapes degrade with age, heat and humidity, and working players are becoming hard to find. Magnetic particles lose strength and the tape itself can become sticky. Once a tape fails, the footage may be gone. In my view, digitizing them soon is wise, and keeping the digital copies in two places protects them properly this time.
At work
Test restores regularly, since tape failures often surface only during recovery. Track tape inventory, labels and chain of custody, store cartridges in climate-controlled conditions, and keep at least one copy offsite. Plan drive compatibility across LTO generations, and migrate archives before the last compatible drive retires. Store encryption keys separately and securely, because a tape encrypted with a lost key is unrecoverable. Tape's air gap makes it a strong ransomware defence.
Real-world examples
At home
Lena's uncle stored decades of company records on tape at his small engineering firm. When ransomware hit, the offline tapes were untouched.
At work
Jerome manages IT for a Saskatoon municipality. Weekly LTO tapes go to an offsite vault, giving an air-gapped backup alongside cloud copies.
How it compares
| feature | Tape backup | Cloud backup |
|---|---|---|
| Cost per TB | Very low | Ongoing monthly fees |
| Restore speed | Slower | Faster for small restores |
| Ransomware isolation | Strong when offline | Strong with immutability |
| Equipment | Drives and media needed | Internet connection |
Tape is cheap and offline. Cloud is convenient and fast.
For analysts
For organizations with large archives or strict retention needs, I'd compare tape's long-term costs with cloud. Tape often wins for data that's rarely restored.
History & origin
IBM introduced magnetic tape storage with the IBM 726 drive in 1952, and tape reels became an iconic image of early computing. Cartridge formats replaced reels from the 1980s. HP, IBM, and Seagate formed the LTO consortium in the late 1990s, and the first LTO drives shipped in 2000. Each generation roughly doubled capacity, with LTO-9 in 2021 holding 18 TB uncompressed and LTO-10 arriving in 2025 at 30 TB, with a 40 TB cartridge following in early 2026. As ransomware attacks grew, offline tape regained interest as a last line of defence, and tape vendors reported strong capacity shipments. In my view, tape is the technology everyone keeps declaring dead that keeps quietly saving businesses.