The Michigan Terminal System (MTS) is one of the first time-sharing computer operating systems.. Created in 1967 at the University of Michigan for use on IBM S/360-67, S/370 and compatible mainframe computers, it was developed and used by a consortium of eight universities in the United States, Canada, and the United Kingdom over a period of 33 years (1967 to 1999)..
Overview The University of Michigan Multiprogramming Supervisor (UMMPS) was initially developed by the staff of the academic computing center at the University of Michigan for operation of the IBM S/360-67, S/370 and compatible computers. The software may be described as a multiprogramming, multiprocessing, virtual memory, time-sharing supervisor that runs multiple resident, reentrant programs. Among these programs is the Michigan Terminal System (MTS) for command interpretation, execution control, file management, and accounting. End-users interact with the computing resources through MTS using terminal, batch, and server oriented facilities.
The name MTS refers to: The UMMPS Job Program with which most end-users interact; The software system, including UMMPS, the MTS and other Job Programs, Command Language Subsystems (CLSs), public files (programs), and documentation; and The time-sharing service offered at a particular site, including the MTS software system, the hardware used to run MTS, the staff that supported MTS and assisted end-users, and the associated administrative policies and procedures.
MTS was used on a production basis at about 13 sites in the United States, Canada, the United Kingdom, Brazil, and possibly in Yugoslavia and at several more sites on a trial or benchmarking basis. MTS was developed and maintained by a core group of eight universities included in the MTS Consortium.
The University of Michigan announced in 1988 that "Reliable MTS service will be provided as long as there are users requiring it ... MTS may be phased out after alternatives are able to meet users' computing requirements". It ceased operating MTS for end-users on June 30, 1996."MTS Service to End", Information Technology Digest, Vol. 5, No. 5 (May 12, 1996), p.7 By that time, most services had moved to client/server-based computing systems, typically Unix for servers and various Mac, PC, and Unix flavors for clients. The University of Michigan shut down its MTS system for the last time on May 30, 1997."MTS Timeline", Information Technology Digest, University of Michigan, pp.10-11, Volume 5, No. 5 (May 13, 1966)
Rensselaer Polytechnic Institute (RPI) is believed to be the last site to use MTS in a production environment. RPI retired MTS in June 1999."MTS Timeline", an after the fact one entry addition for 1999 to Information Technology Digest, University of Michigan, Volume 5, No. 5 (May 13, 1966)
Today, MTS still runs using IBM S/370 emulators such as Hercules, Sim390,Sim390, an ESA/390 emulator and FLEX-ES.FLEX-ES, a S/390 and z/Architecture emulator
Origins In the mid-1960s, the University of Michigan was providing batch processing services on IBM 7090 hardware under the control of the University of Michigan Executive System (UMES), but was interested in offering interactive services using time-sharing."A History of MTS—30 Years of Computing Service", Susan Topol, Information Technology Digest, Volume 5, No. 5 (May 13, 1996), University of Michigan At that time the work that computers could perform was limited by their small real memory capacity. When IBM introduced its System/360 family of computers in the mid-1960s, it did not provide a solution for this limitation and within IBM there were conflicting views about the importance of and need to support time-sharing.
A paper titled Program and Addressing Structure in a Time-Sharing Environment by Bruce Arden, Bernard Galler, Frank Westervelt (all associate directors at UM's academic Computing Center), and Tom O'Brian building upon some basic ideas developed at the Massachusetts Institute of Technology (MIT) was published in January 1966."Program and Addressing Structure in a Time-Sharing Environment", B. W. Arden, B. A. Galler, T. C. O'Brien, F. H. Westervelt, Journal of the ACM, v.13 n.1, p.1-16, Jan. 1966 The paper outlined a virtual memory architecture using dynamic address translation (DAT) that could be used to implement time-sharing.
After a year of negotiations and design studies, IBM agreed to make a one-of-a-kind version of its S/360-65 mainframe computer with dynamic address translation (DAT) features that would support virtual memory and accommodate UM's desire to support time-sharing. The computer was dubbed the Model S/360-65M. The "M" stood for Michigan. But IBM initially decided not to supply a time-sharing operating system for the machine. Meanwhile, a number of other institutions heard about the project, including General Motors, the Massachusetts Institute of Technology's (MIT) Lincoln Laboratory, Princeton University, and Carnegie Institute of Technology (later Carnegie Mellon University). They were all intrigued by the time-sharing idea and expressed interest in ordering the modified IBM S/360 series machines. With this demonstrated interest IBM changed the computer's model number to S/360-67 and made it a supported product. With requests for over 100 new model S/360-67s IBM realized there was a market for time-sharing, and agreed to develop a new time-sharing operating system called TSS/360 (TSS stood for Time-sharing System) for delivery at roughly the same time as the first model S/360-67.
While waiting for the Model 65M to arrive, U of M Computing Center personnel were able to perform early time-sharing experiments using an IBM System/360 Model 50 that was funded by the ARPA CONCOMP (Conversational Use of Computers) Project.CONCOMP: Research in Conversational Use of Computers: Final Report, Westervelt, F. H., University of Michigan Computing Center, 1970 The time-sharing experiment began as a "half-page of code written out on a kitchen table" combined with a small multi-programming system, LLMPS from MIT's Lincoln Laboratory, which was modified and became the U of M Multi-Programming Supervisor (UMMPS) which in turn ran the MTS job program. This earliest incarnation of MTS was intended as a throw-away system used to gain experience with the new IBM S/360 hardware and which would be discarded when IBM's TSS/360 operating system became available.
Development of TSS took longer than anticipated, its delivery date was delayed, and it was not yet available when the S/360-67 (serial number 2) arrived at the Computing Center in January 1967.The IBM 360/67 and CP/CMS, Tom Van Vleck At this time UM had to decide whether to return the Model 67 and select another mainframe or to develop MTS as an interim system for use until TSS was ready. The decision was to continue development of MTS and the staff moved their initial development work from the Model 50 to the Model 67. TSS development was eventually canceled by IBM, then reinstated, and then canceled again. But by this time UM liked the system they had developed, it was no longer considered interim, and MTS would be used at U of M and other sites for 33 years.
MTS Consortium MTS was developed, maintained, and used by a consortium of eight universities in the US, Canada, and the United Kingdom:"How did sites learn about and make the decision to use MTS?", an item in the discussion section of the Michigan Terminal System Archive
University of Michigan (U of M), 1967 to 1997, US University of British Columbia (UBC), 1968 to 1998, Canada NUMAC (University of Newcastle upon Tyne, University of Durham, and Newcastle Polytechnic),"How computers have changed since 1968", ITS News, Computing and Information Services, Durham University, 29 January 2005. Northumbrian Universities Multiple Access Computer (N.U.M.A.C.), a collaboration between of the universities of Durham (DUR), Newcastle upon Tyne (UNE) and Newcastle Polytechnic that shared a S/360-67 at Newcastle starting in 1969 1969 to 1992, United Kingdom University of Alberta (UQV), 1971 to 1994, Canada Wayne State University (WSU), 1971 to 1998, US Rensselaer Polytechnic Institute (RPI), 1976 to 1999, US Simon Fraser University (SFU), 1977 to 1992, Canada University of Durham (NUMAC), 1982 to 1992,In 1982 "How computers have changed since 1968", ITS News, Computing and Information Services, Durham University, 29 January 2005. NUMAC installed a separate machine running MTS at the University of Durham, prior to that both DUR and UNE shared a single MTS system running at the University of Newcastle upon Tyne. United Kingdom
Several sites ran more than one MTS system: NUMAC ran two (first at Newcastle and later at Durham), Michigan ran three in the mid-1980s (UM for Maize, UB for Blue, and HG at Human Genetics), UBC ran three or four at different times (MTS-G, MTS-L, MTS-A, and MTS-I for general, library, administration, and instruction).
Each of the MTS sites made contributions to the development of MTS, sometimes by taking the lead in the design and implementation of a new feature and at other times by refining, enhancing, and critiquing work done elsewhere. Many MTS components are the work of multiple people at multiple sites.It is difficult to properly give credit for all the work that was done, however, to avoid giving too little credit and at the risk of not giving proper credit to everyone that made contributions, an attempt is made to note the sites where a major feature or enhancement was initially developed
In the early days collaboration between the MTS sites was accomplished through a combination of face-to-face site visits, phone calls, the exchange of documents and magnetic tapes by snail mail, and informal get-togethers at SHARE or other meetings. Later, e-mail, computer conferencing using CONFER and *Forum, network file transfer, and e-mail attachments supplemented and eventually largely replaced the earlier methods.
The members of the MTS Consortium produced a series of 82 MTS Newsletters between 1971 and 1982 to help coordinate MTS development.Michigan Terminal System (MTS) subseries, Computing Center publications, 1965-1999, Bentley Historical Library, University of Michigan
Starting at UBC in 1974Proceedings - MTS Systems Workshop, 1974, University of British Columbia, Canada the MTS Consortium held annual MTS Workshops at one of the member sites. The workshops were informal, but included papers submitted in advance and Proceedings published after-the-fact that included session summaries.MTS (Michigan Terminal System) 1970-1986 series, Computing Center (University of Michigan) records, 1952-1996 and 1959-1987, Bentley Historical Library, University of Michigan In the mid-1980s several Western Workshops were held with participation by a subset of the MTS sites (UBC, SFU, UQV, UM, and possibly RPI).
The annual workshops continued even after MTS development work began to taper off. Called simply the "community workshop", they continued until the mid-1990s to share expertise and common experiences in providing computing services, even though MTS was no longer the primary source for computing on their campuses and some had stopped running MTS entirely.
MTS sites In addition to the eight MTS Consortium sites that were involved in its development, MTS was run at a number of other sites, including:
Centro Brasileiro de Pesquisas Fisicas (CBPF)CBPF is the Brazilian Center for Physics Research within the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq),CNPq is the National Council of Scientific and Technological Development Brazil Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA),EMBRAPA is the Brazilian Enterprise for Agricultural Research Brazil Hewlett-Packard (HP), US Michigan State University (MSU), US Goddard Space Flight Center, National Aeronautics and Space Administration (NASA), US