What is 3270 (Information Display System)? - Definition from WhatIs.com

Definition

3270 (Information Display System)

Part of the Hardware glossary:

The 3270 Information Display System, a product from IBM, was, prior to the arrival of the PC, the way that almost the entire corporate world interfaced with a computer. When first produced (the early 1970s), a 3270 display terminal was considered a vast improvement over its predecessor, the 2260.

The 3277 terminal was a non-graphical (text only) monochrome (black screen with green letters) display that buffer ed data so that key strokes could be saved until the ENTER key was pressed. (Previous terminals sent every key stroke immediately to the computer to which the terminal was attached.) The 3277 was also field-oriented rather than line-oriented which meant that a program could write an output data stream to the terminal based on application-oriented fields rather than having to create the display output line by line. A number of 3277s could be attached to a control unit or cluster controller which in turn was attached to an IBM mainframe computer. Terminals could be attached to the computer on a relatively high-bandwidth local link called a channel or remotely over a telecommunication link that was either dedicated (usually a leased line ) or dial-up .

After the personal computer arrived with its own self-sufficient operating system and applications, it gradually replaced the 3270 system in much of the corporate world (although there almost certainly are some working 3270s in use as this is being written). A 3270 terminal became the most prominent example of what became known as a " dumb terminal ," since it relied entirely on its attachment to a mainframe (and sometimes a minicomputer ) for its "brains." The PC attached to a mainframe then became known generically as an " intelligent workstation ." It could run its own programs independently of the mainframe and it could also interface with mainframe applications. There was one product attempt to blend the two, called the 3270 PC.

The terminals themselves were the 3277 (which attached to a control unit), a 3275 standalone terminal (for locations where only a single terminal was needed), the 3278 (a sleeker version of the 3277), and the 3279 color terminal. The control units were the 3271 (channel attachment), 3272 (telecommunication attachment), and the 3274 (a control unit with a smaller form factor that could handle up to 32 terminals). For about 15 years, the 3270 family, one of IBM's most successful products ever, was a ubiquitous feature of offices the world over. The PC changed all that.

However, many thousands of corporate legacy application programs written to interact with users at 3270s are being used from PCs equipped with software known generally as 3270 emulator s. TN3270 is a program that provides PC users remote ( Telnet ) connection to an IBM computer that is running 3270 applications.

This was last updated in March 2011
Contributor(s): Jason Kelley
Posted by: Margaret Rouse

Related Terms

Definitions

  • cache memory

    - Cache memory, also called CPU memory, is random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. (SearchStorage.com)

  • flash storage

    - Flash storage, based on flash memory, is used for data repositories, storage systems and consumer devices, such as USB drives, smartphones and solid-state drives. Flash-based storage is faster than... (WhatIs.com)

  • SSD (solid-state drive, solid-state disk, solid-state storage drive)

    - Definition: Learn what a solid-state drive (SSD) is, why SSDs are replacing electromechanical hard drives and which form factors are approved by the Solid State Storage Initiative (SSSI). (SearchStorage.com)

Glossaries

  • Hardware

    - Terms related to computer hardware, including definitions about cables, connectors and power supply units and words and phrases about computing peripheral devices including the keyboard, mouse, au...

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About 3270 (Information Display System)Powered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.