ESCON (Enterprise Systems Connection) is a data connection created by
IBM, and is commonly used to connect their
mainframe computer
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterpris ...
s to peripheral devices such as
disk storage
Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is ...
,
tape drive
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 a long archival stability.
...
s and
IBM 3270 display controllers. ESCON is an
optical fiber
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparency and translucency, transparent fiber made by Drawing (manufacturing), drawing glass (silica) or plastic to a diameter slightly thicker than that of a Hair ...
,
half-duplex
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow ...
,
serial interface. It originally operated at a rate of 10MB/s, which was later increased to 17MB/s. The current maximum distance is 43 kilometers.
IBM introduced ESCON in September 1990 as part of its System/390 announcement.
[
] It replaced the older, slower (4.5MB/s), copper-based, parallel,
IBM System/360
The IBM System/360 (S/360) is a family of mainframe computer systems that was announced by IBM on April 7, 1964, and delivered between 1965 and 1978. It was the first family of computers designed to cover both commercial and scientific applic ...
Bus and Tag
Bus and Tag is an "IBM standard for a computer peripheral interface", and was commonly used to connect their mainframe computers to peripheral devices such as line printers, disk storage, magnetic tape drives and IBM 3270 display controllers. T ...
channels technology of 1960-1990 era mainframes. Optical fiber is smaller in diameter and weight, and hence could save installation costs. Space and labor could also be reduced when fewer physical links were required - due to ESCON's switching features. ESCON is being supplanted by the substantially faster