Field Guide · hardware

Also known as: tape, LTO

Magnetic tape stores data on a long, thin ribbon of magnetic film wound on reels, written and read sequentially by a tape drive.1

Overview

A drive pulls the tape past a head that magnetises regions to record bits, much like a hard disk drive but on flexible media that must be streamed end to end rather than seeked. The dominant modern format is LTO (Linear Tape-Open), whose cartridges now hold many terabytes each and improve with every generation. Because there are no fast random-access mechanics, the medium itself is extremely cheap, and a tape sitting on a shelf consumes no power and keeps data for decades.

Where it fits

Tape lives at the coldest, deepest end of the memory hierarchy: the slowest access but the lowest cost per terabyte and the longest shelf life, which is exactly what large-scale backup and archival want. Data centres still move petabytes onto LTO for “cold storage.” Its sequential nature suits write-once-read-rarely archives — a fitting place to retire years of GopherTrunk IQ captures that you want to keep but rarely touch, while live decoding stays on SSD or disk.

Sources

  1. Magnetic tape data storage — Wikipedia, on tape storage, LTO, and its role in archival. 

See also