Terminal server

A terminal server connects devices with a serial port to a local area network (LAN). Products marketed as terminal servers can be very simple devices that do not offer any security functionality, such as data encryption and user authentication. The primary application scenario is to enable serial devices to access network server applications, or vice versa, where security of the data on the LAN is not generally an issue. There are also many terminal servers on the market that have highly advanced security functionality to ensure that only qualified personnel can access various servers and that any data that is transmitted across the LAN, or over the Internet, is encrypted. Usually, companies that need a terminal server with these advanced functions want to remotely control, monitor, diagnose and troubleshoot equipment over a telecommunications network. A console server (also referred to as console access server, console management server, serial concentrator, or serial console server) is a device or service that provides access to the system console of a computing device via networking technologies. Although primarily used as an Interface Message Processor starting in 1971, the Honeywell 316 could also be configured as a Terminal Interface Processor (TIP) AND PROVIDE terminal server support for up to 63 ASCII serial terminals through a multi-line controller in place of one of the hosts. Historically, a terminal server was a device that attached to serial RS-232 devices, such as "green screen" text terminals or serial printers, and transported traffic via TCP/IP, Telnet, SSH or other vendor-specific network protocols (e.g., LAT) via an Ethernet connection. Digital Equipment Corporation's DECserver 100 (1985), 200 (1986) and 300 (1991) are early examples of this technology. (An earlier version of this product, known as the DECSA Terminal Server was actually a test-bed or proof-of-concept for using the proprietary LAT protocol in commercial production networks.