A 3270 Emulator is a

terminal emulator A terminal emulator, or terminal application, is a computer program that emulates a video terminal within some other display architecture. Though typically synonymous with a shell or text terminal, the term ''terminal'' covers all remote termin ...

that duplicates the functions of an

IBM 3270 The IBM 3270 is a family of block oriented display and printer computer terminals introduced by IBM in 1971 and normally used to communicate with IBM mainframes. The 3270 was the successor to the IBM 2260 display terminal. Due to the text ...

mainframe computer terminal on a computer, usually a PC or similar

microcomputer A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PC ...

. As the original 3270 series terminals were connected to the

host computer A network host is a computer or other device connected to a computer network. A host may work as a Server (computing), server offering information resources, services, and applications to users or other hosts on the network. Hosts are assigned at ...

through a display controller (cluster controller) using

coaxial cable Coaxial cable, or coax (pronounced ) is a type of electrical cable consisting of an inner conductor surrounded by a concentric conducting shield, with the two separated by a dielectric ( insulating material); many coaxial cables also have a p ...

, emulators originally required channel (rare), coax or synchronous communication adapter cards to be installed in the PC. Today, many emulators communicate with the

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 ...

through a TN3270 server using the

TN3270 The IBM 3270 is a family of block oriented display and printer computer terminals introduced by IBM in 1971 and normally used to communicate with IBM mainframes. The 3270 was the successor to the IBM 2260 display terminal. Due to the text ...

() variant of the

Telnet Telnet is an application protocol used on the Internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control i ...

()protocol common on

TCP/IP The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suit ...

networks including the

Internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

, so special hardware is no longer required on machines with Internet access. Several vendors offered both coax and communications attached 3270 emulators and TN3270 clients as part of the same product.

Connectivity

One way of categorizing a 3270 simulator is by how it connects to the host. Some 3270 simulators use a channel adapter to connect directly to the host. This is common in protocol converters or other situations where performance justifies the higher cost. Some 3270 simulators use a coax adapter such as the

Irma board Irma may refer to: People * Irma (name), a female given name * Irma (singer), full name Irma Pany, a Cameroonian female singer-songwriter Places * Irma, Alberta, Canada, a village * Irma, Lombardy, Italy, a ''comune'' * Irma, Wisconsin, USA, a ...

to connect to a cluster controller. Some 3270 simulators use a synchronous serial link to connect to a communications controller. Using

BSC A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University ...

requires less code, but SDLC with SNA allows more functionality. Some 3270 simulators use a LAN interface to a cluster controller. Contemporary 3270 simulators typically use TN3270 to connect to a TN3270 server on the host.

Products

In 1983, IBM marketed the IBM 3270 PC, a bundled package including a PC, a graphics adapter, 3270 emulation software and coax interface card. 3270 emulators and TN3270 clients are also available from many third-party vendors like

Attachmate Attachmate Corporation is a 1982-founded software company which focused on secure terminal emulation, legacy integration, and managed file transfer software. Citrix-compatibility and Attachment ''Reflection'' were enhanced/added offerings. Hist ...

and

Ericom Ericom Software, Inc. is a Closter, New Jersey-based company that provides web isolation and remote application access software to businesses. Overview Ericom develops and sells Remote Browser isolation technology, available as a cloud service o ...

. Some solutions permitted a coax interface to be shared by workstations in a LAN.

Notes

External links

{{link farm, date=August 2020
x3270
open-source, multi-platform TN3270 client
TN3270
emulator for Linux, Windows, Mac OS X
Virtel
terminal thin-client emulation for 3270 mainframe screens
QWS3270 PLUS
a TN3270 client by Jolly Giant Software
QWS3270 Secure
a TN3270E client by Jolly Giant Software
Vista tn3270
a TN3270 emulator by Tom Brennan Software
Rocket BlueZone
a 3270 terminal emulator by Rocket Software
Nexus Terminal
a TN3270/TN5250, SSH, SFTP/FTPS and printer client by Nexus Integration
FlexTerm
a TN3270 client by FlexSoftware Inc

a TN3270 client by Mochasoft

a TN3270 client by Attachmate
Host Explorer
a TN3270 client by OpenText (formerly Hummingbird)
Personal Communications
PCOMM: a 3270 emulator and TN3270 client by IBM
tn3270 X
a TN3270 emulator for Mac OS from Brown University
Flynet Viewer
a web-based client by Flynet
Host Access for the Cloud
a highly available, cloud deployed, web-based client by Micro Focus

Fastest, Most Functional Web Terminal Emulator by Inventu
TNZ emulator
a python 3.6+ library / emulator may interest you if you write software that automates 3270 terminal interactions or if you just use a 3270 terminal emulator. Terminal emulators

Connectivity

Products

See also

Notes

External links