What is a Terminal Emulator, and how can I tell if it's a good one?

A terminal emulator is a software program that enables a computer to communicate with programs that usually reside on a midframe or mainframe computer. In the past these networks used to depend on terminals used exclusively for that purpose. Since that technology has ceased to be developed and manufactured it has become increasingly difficult and expensive to replace or repair these terminals, and thus the need arose for an inexpensive alternative.

Terminal emulation software is usually installed on some or all PCs (or terminal servers) in a network. This enables users to work locally on regular PC or workstation programs, and also to open a window and work directly with mainframe applications. The terminal emulator runs like any other PC or workstation application as a separate program task, providing its own window to the user.

The user interface of a terminal emulator normally emulates the look and feel of the old mainframe or other legacy network terminal, although a good terminal emulator should offer possibilities for custom GUI development, interfacing with third party software, user assignable keys, user selectable colors and rich text formatted (RTF) network printing.

The following list of features could serve as a guideline in selecting a terminal emulator:

1.    Terminal Emulation

Support for the most-used terminals, including::

IBM 3270/8/9/E with full TN3270E support

*IBM 5250,

DEC VT100/220/330, ANSI, SCO ANSI, Linux console

Data General D211,

HP 700/92,

*Sperry UTS60,

*Burroughs T27 (TD830 / ET1100)

Easy key mapping with over 750 function keys.

A version written in Java for use in any Java enabled operating system or browser.

A version for JavaScript and XML-enabled browsers, via web server.

Screen and host printing to multiple remote printers.

Windows programs with COM/Automation interface.

Full script language including special functions like:

Execute external Windows programs.

Addressable cursor.

IP and MAC address reporting.

Screen and data stream reading.

Colour and 132-column operation.

Multiple sessions.

Mouse support with copy and paste and custom automation.