Editing Multics (section)

==Project history==
In 1964, Multics was developed initially for the [[GE-645]] mainframe, a [[36-bit]] system. GE's computer business, including Multics, was taken over by Honeywell in 1970; around 1973, Multics was supported on the [[Honeywell 6000 series|Honeywell 6180]] machines, which included security improvements including hardware support for [[protection ring]]s.

Bell Labs pulled out of the project in 1969; some of the people who had worked on it there went on to create the [[Unix]] system. Multics development continued at MIT and General Electric. At MIT in 1975, use of Multics was declining and did not recover by 1976 to prior levels.<ref>{{cite journal |author=<!--Staff writer(s); no by-line.--> |date=December 1975 |title=Report of the President |url=https://libraries.mit.edu/archives/mithistory/presidents-reports/1975.pdf |journal=Massachusetts Institute of Technology Bulletin |volume=111 |issue=4 |pages=355 |access-date=April 12, 2022 |quote=Use of the Multics service, operated on the Honeywell 6180 system, declined...a decrease of 15 percent. |archive-date=April 13, 2022 |archive-url=https://web.archive.org/web/20220413015059/https://libraries.mit.edu/archives/mithistory/presidents-reports/1975.pdf |url-status=dead }}</ref><ref>{{cite journal |author=<!--Staff writer(s); no by-line.--> |date=November 1976 |title=Report of the President |url=https://libraries.mit.edu/archives/mithistory/presidents-reports/1975.pdf |journal=Massachusetts Institute of Technology Bulletin |volume=112 |issue=4 |pages=392 |access-date=April 12, 2022 |quote=... the demise of several Multics projects which failed to obtain funding. |archive-date=April 13, 2022 |archive-url=https://web.archive.org/web/20220413015059/https://libraries.mit.edu/archives/mithistory/presidents-reports/1975.pdf |url-status=dead }}</ref> Finally by slashing prices, MIT managed to lure users back to Multics in 1978.<ref>{{cite web |author=<!--Staff writer(s); no by-line.--> |date=1978 |title=Report of the President and the Chancellor |url=https://libraries.mit.edu/archives/mithistory/presidents-reports/1978.pdf |publisher=Massachusetts Institute of Technology |page=450 |access-date=April 12, 2022 |quote=This new pricing proved so attractive to many people, however, that Multics users and usage increased considerably. |archive-date=April 13, 2022 |archive-url=https://web.archive.org/web/20220413021106/https://libraries.mit.edu/archives/mithistory/presidents-reports/1978.pdf |url-status=dead }}</ref>

In 1974 Honeywell entered into a development contract with the Air Force (with MIT as a sub-contractor) to develop a [[security kernel]] for Multics. This would involve reducing the size of the Multics hardcore by moving specific components of the supervisor out of Ring 0. One of the initial steps after carrying out a security evaluation was the implementation of a [[multilevel security]] framework within Multics called AIM (Access Isolation Mechanism). This provided [[mandatory access control]] which could be enabled to supplement the already existing [[discretionary access control]] that Multics already possessed.<ref name="MDS">{{cite web |title=Multics Data Security |url=https://multicians.org/multics-data-security.html |website=multicians.org}}</ref> The resulting Project Guardian ran until termination in 1976; whilst most of its changes were not added to Multics, some parts of the project such as the proposed Secure Front End Processor was productized by Honeywell as SCOMP (Secure Communications Processor).<ref name="scomp">{{cite journal |last1=Fraim |first1=Lester J. |title=Scomp: A Solution to the Multilevel Security Problem |journal=Computer |date=July 1983 |volume=16 |issue=7 |pages=26–34 |doi=10.1109/MC.1983.1654440 |url=https://ieeexplore.ieee.org/document/1654440|url-access=subscription }}</ref> The SCOMP and its STOP operating system eventually evolved via XTS-200 and XTS-300 into current [[XTS-400]] offering of secure operating systems.<ref>{{cite web |title=STOP OS™ Version 7.3.1 Security Target |url=https://www.commoncriteriaportal.org/files/epfiles/BAE%20STOP%207%20Security%20Target%201.08.pdf |publisher=Common Criteria}}</ref>

Honeywell continued system development until 1985. About 80 multimillion-dollar sites were installed, at universities, industry, and government sites. The French university system had several installations in the early 1980s. After Honeywell stopped supporting Multics, users migrated to other systems, such as Unix.

In 1985, Multics was issued certification as a B2 level secure operating system using the [[Trusted Computer System Evaluation Criteria]] from the [[National Computer Security Center]] (NCSC), a division of the [[NSA]]; it was the first operating system evaluated to this level.

Multics was distributed from 1975 to 2000 by [[Groupe Bull]] in [[Europe]], and by Bull HN Information Systems Inc. in the United States. In 2006, [[Groupe Bull|Bull SAS]] released the source code of Multics versions MR10.2, MR11.0, MR12.0, MR12.1, MR12.2, MR12.3, MR12.4 & MR12.5 under a [[free software]] license.<ref>{{Cite web |title=Multics |url=https://stuff.mit.edu/afs/athena/reference/multics-history/ |access-date=2022-07-25 |website=stuff.mit.edu}}</ref>

The last known Multics installation running [[native (computing)|natively]] on Honeywell hardware was shut down on October 30, 2000, at the Canadian [[Department of National Defence (Canada)|Department of National Defence]] in Halifax, Nova Scotia, Canada.<ref name="urlMultics Dates">{{cite web
| url = http://www.multicians.org/chrono.html
| title = Multics History Dates
| quote = Shutdown of DND-H (17:08Z 10/30/00)
| access-date = 2015-09-13
}}</ref>

===Current status===
In 2006 Bull HN released the source code for MR12.5, the final 1992 Multics release, to MIT.<ref>{{cite web|last1=Van Vleck|first1=Tom|url=http://web.mit.edu/multics-history/#community|title=Open Source for Multics|website=Multicians.org|access-date=April 11, 2016}}</ref> Most of the system is now available as [[free software]] with the exception of some optional pieces such as [[TCP/IP]].<ref>{{cite web|first=Charles|last=Anthony|title=(email) Re: [dps8m-developers] Multiprocessor and/or networked Multics|url=https://sourceforge.net/p/dps8m/mailman/message/34310157/|website=Sourceforge.net|access-date=April 11, 2016}}</ref>

In 2014, Multics was successfully run on current hardware using an emulator created by Multicians Harry Reed and Charles Anthony.<ref>{{cite web|title=RingZero - Multics reborn|url=http://ringzero.wikidot.com/start|website=WikidotCom|access-date=April 11, 2015}}</ref> The 1.0 release of the emulator is available {{As of|2017|lc=y}}.<ref>{{cite web|title=Multics Simulator|url=http://multicians.org/simulator.html|access-date=July 9, 2017}}</ref> Release 12.6f of Multics accompanies the 1.0 release of the emulator, and adds a few new features, including command line recall and editing using the video system.<ref>{{cite web|title=Installing Multics|url=http://multics-wiki.swenson.org/index.php/Main_Page#Installing_Multics|access-date=May 19, 2020}}</ref>