Product Code Database
A tape drive is a data storage device that reads and writes data on a magnetic tape. Magnetic-tape data storage is typically used for offline, archival data storage. Tape media generally has a favorable unit cost and long archival stability.
A tape drive provides sequential access storage, unlike a hard disk drive, which provides random access storage. A disk drive can move to any position on the disk in a few milliseconds, but a tape drive must physically wind tape between reels to read any one particular piece of data. As a result, tape drives have very large average . However, tape drives can stream data very quickly off a tape when the required position has been reached. For example, Linear Tape-Open (LTO) supports continuous data transfer rates of up to , a rate comparable to hard disk drives.
In early computer systems, magnetic tape served as the main storage medium because although the drives were expensive, the tapes were inexpensive. Some computer systems ran the operating system on tape drives such as DECtape. DECtape had fixed-size indexed blocks that could be rewritten without disturbing other blocks, so DECtape could be used like a slow disk drive.
Data tape drives may use advanced data integrity techniques such as multilevel forward error correction, shingling, and linear serpentine layout for writing data to tape.
Tape drives can be connected to a computer with SCSI, Fibre Channel, SATA, USB, FireWire, FICON, or other interfaces. Tape drives are used with autoloaders and tape libraries which automatically load, unload, and store multiple tapes, increasing the volume of data that can be stored without manual intervention.
In the early days of home computing, floppy and hard disk drives were very expensive. Many computers had an interface to store data via an audio tape recorder, typically on Compact Cassettes. Simple dedicated tape drives, such as the professional DECtape and the home ZX Microdrive and Rotronics Wafadrive, were also designed for inexpensive data storage. However, the drop in disk drive prices made such alternatives obsolete.
In early tape drives, non-continuous data transfer was normal and unavoidable. Computer processing power and available memory were usually insufficient to provide a constant stream, so tape drives were typically designed for start-stop operation. Early drives used very large spools, which necessarily had high inertia and did not start and stop moving easily. To provide high start, stop and seek performance, several feet of loose tape was played out and pulled by a suction fan down into two deep open channels on either side of the tape transport. The long thin loops of tape hanging in these vacuum columns had far less inertia than the two reels and could be rapidly started, stopped and repositioned. The large reels would move as required to keep the slack tape in the vacuum columns.
Later, most tape drives of the 1980s introduced the use of an internal data buffer to somewhat reduce start-stop situations. These drives are often referred to as tape streamers. The tape was stopped only when buffer underrun, or when it was full of data during reading. As faster tape drives became available, despite being buffered, the drives started to suffer from the shoe-shining sequence of stop, rewind, start.
Some newer drives have several speeds and implement algorithms that dynamically match the tape speed level to the computer's data rate. Example speed levels could be 50 percent, 75 percent and 100 percent of full speed. A computer that streams data slower than the lowest speed level (e.g., at 49 percent) will still cause shoe-shining.
| 1951 | Remington Rand | UNISERVO | First computer tape drive, used " nickel-plated phosphor bronze tape | |
| 1952 | IBM | 726 | Use of plastic tape (cellulose acetate); 7-track tape that could store every 6-bit byte plus a parity bit | |
| 1953 | IBM | 727 | ||
| 1958 | IBM | 729 | Separate read/write heads providing transparent read-after-write verification. | |
| 1961 | IBM | 7340 | 10-track 1" tape cartridge that could store every 8-bit byte plus a parity bit. | |
| 1964 | IBM | 24xx | 9-track tape that could store every 8-bit byte plus a parity bit | |
| 1970s | IBM | 34xx | Auto-loading tape reels and drives, avoiding manual tape threading 6250 BPI with Group coded recording (GCR) for error recovery | |
| 1972 | 3M | Quarter Inch Cartridge (QIC-11) | Tape cassette (with two reels) Linear serpentine recording | |
| 1974 | IBM | 3850 | Tape cartridge (with single reel) First tape library with robotic access | |
| 1975 | (various) | Kansas City standard | Use of standard audio cassettes | |
| 1977 | Commodore International | Commodore Datasette | ||
| 1980 | Cipher | (F880?) | RAM buffer to mask start-stop delays | |
| 1984 | IBM | 3480 | 200 MB | Internal takeup reel with automatic tape takeup mechanism. Thin-film magnetoresistive (MR) head |
| 1984 | DEC | TK50 | Digital Linear Tape (DLT) line of products | |
| 1986 | IBM | 3480 | Hardware data compression (IDRC algorithm) | |
| 1987 | Exabyte/Sony | EXB-8200 | First helical digital tape drive Elimination of the capstan and pinch-roller system | |
| 1993 | DEC | Tx87 | Tape directory (database with first tapemark nr on each serpentine pass) | |
| 1995 | IBM | 3570 | Servo tracks - factory-recorded tracks for precise head positioning (Time Based Servoing or TBS) Tape on unload rewound to the midpoint—halving access time (requires two-reel cassette) | |
| 1996 | Hewlett-Packard | DDS3 | Partial-response maximum-likelihood (PRML) reading method—no fixed thresholds | |
| 1997 | IBM | IBM VTS | Virtual tape—disk cache that emulates tape drive | |
| 1999 | Exabyte | Mammoth-2 | Small cloth-covered wheel for cleaning tape heads. Inactive burnishing heads to prep the tape and deflect any debris or excess lubricant. Section of cleaning material at the beginning of each data tape. | |
| 2000 | Quantum | Super DLT | Visual Servoing precisely positioning the heads | |
| 2000 | Linear Tape-Open | LTO-1 | ||
| 2003 | IBM | 3592 | Virtual backhitch | |
| 2003 | Linear Tape-Open | LTO-2 | ||
| 2003 | Sony | SAIT-1 | Single-reel cartridge for helical recording | |
| 2005 | IBM | TS1120 | ||
| 2005 | Linear Tape-Open | LTO-3 | ||
| 2006 | StorageTek | T10000 | Multiple head assemblies and servos per drive | |
| 2007 | Linear Tape-Open | LTO-4 | ||
| 2008 | IBM | TS1130 | Encryption capability integrated into the drive | |
| 2008 | StorageTek | T10000B | ||
| 2010 | Linear Tape-Open | LTO-5 | Linear Tape File System (LTFS), which allows accessing files on tape in the file system directly (similar to disk filesystems) without an additional tape library database | |
| 2011 | IBM | TS1140 | Linear Tape File System (LTFS) supported | |
| 2011 | StorageTek | T10000C | Linear Tape File System (LTFS) supported | |
| 2012 | Linear Tape-Open | LTO-6 | ||
| 2013 | StorageTek | T10000D | ||
| 2014 | IBM | TS1150 | ||
| 2015 | Linear Tape-Open | LTO-7 | ||
| 2017 | IBM | TS1155 | ||
| 2017 | Linear Tape-Open | LTO-8 | ||
| 2018 | IBM | TS1160 | ||
| 2021 | Linear Tape-Open | LTO-9 | ||
| 2023 | IBM | TS1170 | 50 TB |
In 2011, Fujifilm and IBM announced that they had been able to record 29.5 billion bits per square inch with magnetic-tape media developed using Barium Ferrite (BaFe) particles and nanotechnologies, allowing drives with true (uncompressed) tape capacity of 35 TB. The technology was not expected to be commercially available for at least a decade.
In 2014, Sony and IBM announced that they had been able to record 148 billion bits per square inch with magnetic tape media developed using a new vacuum thin-film forming technology able to form extremely fine crystal particles, allowing true tape capacity of 185 TB.
On December 15, 2020, Fujifilm and IBM announced a Strontium Ferrite (SrFe) technology able, in theory, to store 580 TB per tape cartridge.
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