SIMTEL20

Simtel, sometimes cited as Simtelnet, was an important long-running archive of freeware and shareware for various operating systems.

The Simtel archive had significant ties to the history of several operating systems: it was in turn a major repository for CP/M, MS-DOS, Microsoft Windows and FreeBSD. The archive was hosted initially on TOPS-20, then FreeBSD servers, with archive distributor Walnut Creek CDROM helping fund FreeBSD development. It began as an early mailing list, then was hosted on the ARPANET, and finally the fully open Internet.

The service was shut down on March 15, 2013.

Simtel originated as SIMTEL20, a software archive started by Keith Petersen in 1979 while living in Royal Oak, Michigan. The original archive consisted of CP/M software for early 8080-based microcomputers. The software was hosted on a PDP-10 at MIT that also ran a CP/M mailing list Mr. Petersen subscribed to.

When access to the particular MIT computer was removed in 1983, fellow CP/M enthusiast Frank Wancho, then an employee at the White Sands Missile Range, arranged for the archive to be hosted on a DECSYSTEM-20 computer with ARPANET access, accessible via FTP at simtel20.arpa, later known as wsmr-simtel20.army.mil. At this time, Simtel began archiving MS-DOS software in addition to its archive of CP/M software. Over time, the SIMTEL20 archive added software for other operating systems, user groups and various programming languages, including the Ada Software Repository, the CP/M User's Group, PC/Blue, SIG/M(icros), and the Unix/C collections. In 1991, Walnut Creek CDROM was founded by Robert A. Bruce, which helped distribute the Simtel archive on CD-ROM discs for those not wishing, or unable, to access the archive online.

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