NCSA Telnet is an implementation of the

Telnet Telnet (sometimes stylized TELNET) is a client-server application protocol that provides access to virtual terminals of remote systems on local area networks or the Internet. It is a protocol for bidirectional 8-bit communications. Its main ...

protocol developed at the

National Center for Supercomputing Applications The National Center for Supercomputing Applications (NCSA) is a unit of the University of Illinois Urbana-Champaign, and provides high-performance computing resources to researchers in the United States. NCSA is currently led by Professor Bill ...

of the

University of Illinois at Urbana-Champaign The University of Illinois Urbana-Champaign (UIUC, U of I, Illinois, or University of Illinois) is a public land-grant research university in the Champaign–Urbana metropolitan area, Illinois, United States. Established in 1867, it is the f ...

, first released in 1986 and continuously developed until 1995. The initial implementation ran under

Mac OS Mac operating systems were developed by Apple Inc. in a succession of two major series. In 1984, Apple debuted the operating system that is now known as the classic Mac OS with its release of the original Macintosh System Software. The system ...

and Microsoft

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

, and provided basic DEC VT102 terminal emulation with support for multiple simultaneous connections and an

FTP The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and dat ...

client. NCSA Telnet was the first implementation of telnet for the Macintosh or PC that provided the ability to connect to multiple hosts simultaneously. Over time, the program evolved with added features and revisions to the user interface. Support for

Tektronix 4010 The Tektronix 4010 series was a family of text-and-graphics computer terminals based on storage-tube technology created by Tektronix. Several members of the family were introduced during the 1970s, the best known being the 11-inch 4010 and 19-in ...

/4014 vector terminal emulation and a protocol for downloading and viewing raster images were added. In 1987, a short-lived version for

Sun Microsystems Sun Microsystems, Inc., often known as Sun for short, was an American technology company that existed from 1982 to 2010 which developed and sold computers, computer components, software, and information technology services. Sun contributed sig ...

SunOS SunOS is a Unix-branded operating system developed by Sun Microsystems for their workstation and server computer systems from 1982 until the mid-1990s. The ''SunOS'' name is usually only used to refer to versions 1.0 to 4.1.4, which were based ...

was released. Although the MS-DOS version of NCSA Telnet lost popularity after Microsoft Windows became widespread, the

Macintosh Mac is a brand of personal computers designed and marketed by Apple Inc., Apple since 1984. The name is short for Macintosh (its official name until 1999), a reference to the McIntosh (apple), McIntosh apple. The current product lineup inclu ...

version remained in use throughout the 1990s as a basic connectivity tool in academic and commercial installations. NCSA Telnet originally used a built-in

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

protocol stack to communicate over the network. As standard APIs became available for network communication, the program was adapted to use them, most notably Apple's

MacTCP MacTCP is the standard TCP/IP implementation for the classic Mac OS through version 7.5.1. It is the first application-independent implementation of a TCP stack for a non-Unix platform and predates Winsock by over 5 years. Released in 1988, it is ob ...

. However, the built-in stack, one of the few completely independently developed TCP/IP stacks in use at the time, continued to ship in the software for years. NCSA Telnet was released as

free and open source Free and open-source software (FOSS) is software available under a license that grants users the right to use, modify, and distribute the software modified or not to everyone free of charge. FOSS is an inclusive umbrella term encompassing free ...

software (although the term "open source" was not yet in use), and as such spawned a number of spin-off products including * BetterTelnet * Brown tn3270 * BYUTelnet * InterCon's TCP/Connect series * MacBlue Telnet (Chinese-language version) * MacTelnet * NCSA Telnet-J (Japanese-language version)

References

External links

*{{cite web , title=NCSA PC Telnet Info Page , publisher=NCSA, date=28 September 2000 , url=http://archive.ncsa.uiuc.edu/SDG/Software/PCTelnet/ , archive-url=https://web.archive.org/web/20051225232051/http://archive.ncsa.uiuc.edu/SDG/Software/PCTelnet/ , archive-date=25 December 2005 , url-status=dead Free terminal emulators 1986 software Clear text protocols History of the Internet Telnet