Mainframe Computers By: Lyndsey Farris Mainframe Computers are large and expensive computers that were used for large organizations, mostly government agencies and banks to process manage and store data. Their purpose was to store large quantities of information like censuses, bank transaction processing, and industry and consumer statistics. (Wikipedia, 2005) To classify a computer as a Mainframe it has to have 1 to 16 CPU s (Central Processing Units), memory ranges from 128 Mb over 8 Gigabytes on line RAM. Its processing power ranges from 80 over 550 MIPS. The mainframe has different cabinets for storage. I/O and RAM or separate processes programs that are often found on the mainframe are task management, program management, job management, sterilization, catalogs, inter address space and communication. When mainframes first came out, they didn t operate on their own. You had to have an operator switching wires and setting switches to have the machine calculate a table. Mostly, these operators were engineers. Eventually, programming came out and mainframes were able to operate on their own without an operator setting the switches. These made it easier for scientists to program something and immediately receive an answer. (Mainframe Introduction, 2004) The actual mainframe is usually in an air-conditioned, humidity controlled room. The term mainframe computers didn t arise until the 1970 s when smaller Personal Computers (PC s) were introduced. (Wikipedia, 2005) PC s can even be hooked up to a mainframe computer to serve as a terminal. (Mainframe Introduction, 2004) Mainframes are known for their size, but they are also known for their high quality technical support. Mainframes could run for long periods of time without any repair. Unlike today, even
our small PC s require a lot of constant maintenance due to the increase in computer viruses. Mainframe vendors would provide on-site maintenance when something went wrong. (Wikipedia, 2005) As recently as 2004, IBM dominates the mainframe market by 90%. (Wikipedia, 2005) In the late 1990 s most mainframe manufactures started to get away from the market believing that there wasn t a place for mainframe anymore. IBM being left in started new innovations and dictating their own prices which increased sales and profits for IBM. Along with that competition started to rise again. (Mainframe Introduction, 2004) Unisys and Fujitsu are still a part of the mainframe market. However Hitachi is no longer in the mainframe market, except they just co-designed one with IBM. (Wikipedia, 2005) When mainframes first started being built, one would need a few hundred thousand dollars. The 60 s and 70 s models would require a few thousand dollars. (Mainframe Introduction, 2004) As of today, IBM mainframes start under $200,000. In the 1960 s and 1970 s when mainframes were in high demand, companies such as IBM and the Seven Dwarfs, Burroughs, Control Data Corporation, General Electric, Honeywell, NCR, RCA and Univac were the top companies in innovation of the mainframe computer. In the 1980 s the demand for mainframes greatly decreased and the competition got tough. RCA sold to Univac and Univac merged with Sperry which became Sperry/Univac, which later merged with Burroughs to form Unisys Corporation in 1986. Honeywell was bought out by Bull and GE left the market. Mainframes were being replaced at this time by the Personal Computer. However, in the late 1990 s businesses were starting to find a use for the mainframe again. Businesses were attracted to the low maintenance, lower power and administration
costs, plus they can offer web server performance similar to smaller machines. IBM s mainframe revenue is increasing with lower costs as well. The newest trend in mainframes is the Linux operating system. It can run on many mainframe systems and it allows companies and government agencies to use software and developmental expertise from an open source community, but also with low per-user costs and high reliability. (Wikipedia, 2005) In 1935, John Vincent Atanasoff was a physicist at Iowa State University. His students worked with linear partial differential equations. Atanasoff experimented with analog and then digital to aid in the students solutions. One evening at an Illinois tavern, he made four decisions. The first decision was to use electronics and electricity (which meant vacuum tubes then). The second decision was to use base 2 for economy. The third decision was to use condensers and regenerate them and lastly to compute by direct action. With that Atanasoff and graduate student Clifford Berry built the Atanasoff- Berry Computer (ABC), which was the first mainframe computer. (Atanasoff Berry Computer, 2005) According to Iowa State University s website it was built 1937-42. (Iowa State University, 2004) However according to Atanasoff Berry Computer s website, a prototype was built in 1939 and a full scale model was built in 1942. At the time it wasn t considered a modern computer because of the lack of programming control and didn t have a general purpose. The ABC was the first of many to use electronics for calculations and logic. (Atanasoff Berry Computer, 2005) Binary arithmetic, regenerative memory, parallel processing, and separation of memory and computing functions were the uses this computer was intended for. For many years, the ENIAC (which I will discuss later) was though to be the first mainframe or digital computer.
However in 1973, the ENIAC patent was declared invalid and Atanasoff was named the inventor of the first electronic digital computer. (Iowa State University, 2004) Harvard University started working on the Mark I Calculator in 1941 with Howard Aiken in charge. Through the use of banks of electromechanical relays that served as on and off switches, this calculator had 23 decimal places, 4 arithmetic operations, programs that could do logarithmic and trigonometric functions. At the time it could complete tasks that would take someone 6 months to do. However, it was soon replaced by the ENIAC. (Mainframe History, 1986) At Moore School of Electrical Engineering at University of Pennsylvania, the ENIAC (Electronic Numerical Integrator and Computer) was invented. This was supposed to be the first operational, general, electronic digital computer. Of all the developments made during World War I, the ENIAC was one of the most influential. The ENIAC could compute a thousand times faster than any machine before it s time. Throughout World War I, there were some machines made to help war efforts, however, they needed more. They decided to try to invent some kind of electrical calculating machines. After meeting with International Business Machines (IBM) in 1938 to seek help in these efforts, they didn t have enough funds, until 1941 when a tabulator and a multiplier were delivered. In June 1942, with the United States getting involved with World War II, Ballistic Research Laboratory (BRL) needed a machine that operated faster for the Army. (Moye, Jan. 1996) In the spring of 1943, BRL picked up on a proposal that had been put out to them to the Moore School of Electrical Engineering to design and built an electronic calculator for ballistic works. (Hendry, 1989) The Ordnance Department contracted with
Moore School to operate its faster Bush differential analyzer for the Army. Captain Paul N. Gillon, at BRL, requested that Lieutenant Herman H. Goldstine be assigned to duty at the Moore School serving as supervisor of computational and training activities. Goldstine was now working with very talented scientists and engineers. Two very important ones were Dr. John W. Mauchly, a physicist, and J. Presper Eckert, Jr., an engineer. Mauchly had come to Pennsylvania after meeting with John Atanasoff in 1941 of later works on the digital computer. In fall of 1942, Mauchly had sketched his ideas on an electronic computer. Early in 1943 a proposal was being worked on to present to the Chief of Ordinance at BRL. That was presented in April and a contract was signed in June. This project was named Project PX. The original contract between BRL and Moore School was $61,700. However, supplements extended the work that increased the total to $486,804.22. In late 1943 or early 1944, the makers of the ENIAC decided to work on solving one of the biggest problems with the ENIAC, the fact that it wasn t able to store programs. The program was originally designed by manually setting up switches and cable connections. As the project went on, the inventors of the ENIAC would work on a computer innovation that would store programs. In August 1944, Scientist and Mathematician John von Neumann of the Institute of Advanced Studies (IAS) at Princeton and a member of BRL s Scientific Advisory Board joined the ENIAC project. Construction began in June 1944, the final assembly in the fall of 1945 and formal dedication in 1946. (Moye, Jan. 1996) The ENIAC had 18,000 vacuum tubes and could perform 5,000 addition and subtraction, 350 multiplication and 50 division problems per second. It doubled the size of the Mark I (18 ft. by 80 ft.) (Mainframe History, 1986)
The ENIAC s first project was to solve a problem for the Manhattan Project. In late 1946, the ENIAC was dismantled and shipped to Aberdeen arriving in January 1947. It was in working condition again in August 1947. It represented the largest collection of interconnected electronic circuitry then in existence. While the ENIAC was one of the first most influential computers, it was discovered during the construction and training of the ENIAC that a smaller more compact computer was possible and desirable to serve peoples needs better, mostly for mathematical calculations. In 1948 after the reassembly took place at Aberdeen the ENIAC was converted into an internally storefixed program computer through the use of a converter code. Eventually through the years, an independent motor-electricity generator set was installed to provide steady, reliable power, along with a high speed electronic shifter and a 100-work static magneticcore memory which was done by Burroughs Corporation. The ENIAC was retired from 1948-1955. It was operated for 80,223 hours. The ENIAC became available to universities for use, free of charge. After seeing the ENIAC at Aberdeen s train station von Neumann became very involved with the recommendation of the development of the EDVAC (Electronic Discrete Variable Computer). The EDVAC s purpose was to be able to have stored memory. In October 1944, the Ordnance Department approved $105,600 in funds to start development on the EDVAC. Von Neumann wrote the First Draft of a Report on the EDVAC. This was very controversial and a lot of the members of the team weren t thrilled that their contributions weren t mentioned in this draft. It later led to the breakup of the team. (Moye, Jan.1996) Mauchly and Eckert started their own company after the ENIAC in March 1946
called Electronic Control Company (ECC). (Bergin) However, it was hard for them to sell their computer to institutions because of the high cost of $500,000/computer and $1,800/month on electric. (Mainframe History, 1986) In 1946, NBS (National Bureau of Standards) started to have discussions with Eckert and Mauchly about the possible use of computers by the Census Bureau. They collaborated with the IAS on input and output devices for this computer and negotiated on behalf of the Navy for the construction of a computer for naval use by the military electronics company, Raytheon. (Hendry, 1989) In July and August of 1946, 48 lectures were given at the Moore School called Theory and Techniques for the Design of Electronic Digital Computers Even though Mauchly and Eckert had their own company they were still two of the main lecturers. Many people though that the lectures would be about the ENIAC, but they were mostly about the new EDVAC. Enough information was distributed to where the design of the EDVAC was the basis design for other computers after that. The most important were the EDSAC (Electronic Delay Storage Automatic Computer) and the Mark I. Even with the breakup BRL still had a contract with Moore School. Basic construction of the EDVAC was performed at Moore School but it was moved to Aberdeen, which became its permanent location in August 1949. (Moye, Jan. 1996) Also, in 1949 the Raytheon Company s computer called the RAYDAC was still far from complete but the company was planning other projects. By 1950 it had indicated its intentions of building commercially available computers based on the RAYDAC. In the end, they did supply a lot of computers to the military. (Hendry, 1989) Even though EDVAC was for the most part complete, it didn t run its first test for two years in October 1951. From what I gather, this was not tested for that long due to
intimidation of the machine itself. When the machine was finished, it was not what von Neumann originally designed. It had been tweaked throughout the process of designing and building of the EDVAC. (Moye, Jan. 1996) The Raytheon s RAYDAC was based on EDVAC s proposals and completed in 1952. (Hendry, 1989) Not too long after the EDVAC was being used quite a bit, another machine was already getting more use, the ORDVAC (Ordinance Variable Automatic Computer) which was installed in 1952. The ORDVAC s basic logic was developed by von Neumann s group at IAS. (Moye, Jan. 1996) In December 1947, they re-founded their company; it was then called Eckert Mauchly Computer Corporation (EMCC). (Bergin) Eckert and Mauchly contracted with the U.S. Census Bureau, which provided them with enough funds to start working on their second digital computer, the BINAC, which helped calculate the 1950 census. (Mainframe History, 1986) Eckert and Mauchly secured a contract with Northrop Aviation to build the BINAC, which was a small computer that was part of a program of guided missile developed being funded by Air Force. (Hendry, 1989) In September 1949, the BINAC was delivered to Northrop Aviation. (Bergin) This is regarded as the first fully operational computer in American and second or third in the world. (Hendry, 1989) After the BINAC, they had enough money left over to start working on the UNIVAC (Universal Automatic Computer). (Mainframe History, 1986) However, Eckert and Mauchly started having financial problems and had to sell EMCC to Remington-Rand in February 1950. (Bergin) (Mainframe History, 1986) With enough financial backing, they were able to complete their first project. With von Neumann s stored memory it made the computer
automatic. This meant that the computer didn t have to constantly be monitored by engineers all the time. (Mainframe History, 1986) After the completion of the UNIVAC, it was delivered to the U.S. Census Bureau on March 31, 1951. (Bergin) (Mainframe History, 1986) Another 45 were eventually built. (Hendry, 1989) There ended up being 43 UNIVAC s delivered to different government organizations. The memory could only hold 1000 words of 12 alphanumeric characters and it had 45 operational codes. (Bergin) Engineering Research Associates (ERA) was operating on a commercial basis contracted by the Navy. Eventually it was taken over by Remington Rand. After the ERA s completion of the Atlas in 1950, ERA had more projects ahead of them. The Navy gave them permission to sell the Atlas commercially as ERA 1101. Only 1 was made. Then ERA 1102, a special purpose version was introduced. It was specifically designed for an online control project for the Air Force and 3 machines were supplied. ATLAS II started to be developed, together with a variant of it for missile control. There weren t enough funds to complete the project and this is when ERA was purchased by Remington-Rand. Now 340 engineers were employed for the ATLAS II project. ATLAS II, which was ERA 1103 when it was sold commercially with permission of the Navy and 20 were built in all. IBM (International Business Machines) was America s leading manufacturer in data processing equipment. IBM had begun research on an electromechanical calculator with Harvard University before WWII. After a conflict with IBM s president Thomas J. Watson, Sr. and Harvard s leading researcher of this project, Howard Aiken. Aiken continued research by himself and IBM had their project completed by 1948. It was the
SSEC (Selective Sequence Electronic Calculator), which was a large hybrid electronicelectromechanical calculator. In 1949, Thomas Watson Jr. supported a project that Ralph L. Palmer (IBM engineer researcher) and his team were working on. It was an experimental computer using magnetic tape input and output, The Tape Processing Machine. Watson, Jr. argued that there was enough government demand to support the construction ahead of any firm orders, of 20 special purpose computers as part of the Korean War effort. Watson, Sr. didn t agree with his son s proposal. However, after much debate the Defense Calculator, eventually renamed IBM 701 was created in 1952. (Hendry, 1989) (IBM: Archives, 1950 s) It was a general purpose computer with Williams s tube and magnetic drum storage and punches card and magnetic tape input and output. It also had standardized packaged circuitry. (Hendry, 1989) This was IBM s first large computer based on vacuum tubes. These tubes were quicker and smaller. The IBM 701 executed 17,000 instructions per second and was mostly used for government and research work. (IBM: Archives, 1950 s) Nineteen IBM 701 series computers were produced and supplied over the next 4 years. The Tape Processing computer was developed into a business computer called the IBM 702 and it was first delivered in 1954. (Hendry, 1989) The IBM 7090 was one of the first fully transistorized mainframes that could perform 229,000 calculations per second. The U.S Air Force used the 7090 to run its Ballistic Missile Early Warning System. (IBM: Archives: 1950 s) It was introduced on December 30, 1958 and withdrawn on July 14, 1969. The 7090 greatly sped up the design of missiles, jet engineers, nuclear reactors and supersonic aircraft. The 7090 also
processed large scale business applications such as inventory control, production control, forecasting and general accounting. (IBM: 7090 Data Processing System) On April 7, 1964 IBM introduced System/360. It was the first large family of computers to use interchangeable software and peripheral equipment. Fortune magazine dubbed it IBM s $5 billion gamble. System/360 offered a choice of 5 processors and 19 combinations of power, speed and memory. A single user could operate the same magnetic tape and disk products as another user with a processor 100 times more powerful. (IBM Archives: 1960 s) Another series of systems was introduced by IBM called System/370. It was able to run System/360 programs. However, System/370 was one of the first lines of computers to include Virtual Memory technology. This was a technique that was developed in England, 1962. It was developed to expand the capabilities of the computer by using space on the hard drive to accommodate the memory requirements of software. The System/370 Model 145 was the first general purpose business computer to use monolithic circuits in all memory and logic functions, and used semiconductor technology rather than magnetic cores. (IBM Archives: 1970) Mainframe computers have been around for decades. They have been the central processing tools, data storage devices, and calculating mechanisms for banking and governmental agencies. As technological advances have been made throughout the years, so have the advances in capabilities. In the beginning mainframe computers were most significantly applied in war scenarios and were incapable of storing data in memory nor could they perform commands on their own. As time passed and advances were made the computers were capable of storing program data and could calculate at a
significantly more rapid rate. Once PC s were introduced in the 1970 s and 1980 s, mainframes took a back seat as the technological world shifted its operating demands. Finally, in the 1990 s the mainframe computers were back in demand because of their more maintenance free approach. IBM took the market by storm becoming the dominant manufacturer of the mainframe computer systems that are currently in today s business societies.
Bibliography Atanasoff Berry Computer-ABC (1935 USA) Last updated: February 2, 2005 History of Computing Project Retrieved March 8, 2005 from http://www.thocp.net/hardware/abc.html Bergin, Thomas. J, (date unknown) Mainframe Computers. Computer History Museum- American University Retrieved March 8, 2005 from http://www.computinghistorymuseum.org/teaching/lectures/pptlectures/9- mainframecomputers.ppt Websites Bibliography: Mauric V. Wilkes, Memoirs of a Computer Pioneer, MIT Press, 1985 David E. Lundstrom, A Few Good Men From UNIVAC, MIT Press, 1987 Charles J. Bashe, et.al, IBM s Early Computers, MIT Press, 1986 Emerson Pugh, et.al, IBM s 360 and Early Systems, MIT Press, 1991 Caminar, et.al., LEO, The Incredible Story of the World s First Business Computer, McGraw-Hill, 1998 Lavington, Early British Computers, Digital Press, 1980 Hendry, Innovation for Failure: Government Policy and the Early British Computer Industry, MIT Press, 1989 Hendry, John, (1989) Computer Technology and Its Commercial Exploitation in Postwar America. Massachusetts Institute of Technology, Innovation for Failure (pp. 23-32) IBM (date unknown) IBM Archives: 1950 s. Retrieved February 17, 2005 from http://www-03.ibm.com/ibm/history/history/decade_1950.html IBM (date unknown) IBM Archives: 1960 s. Retrieved February 17, 2005 from http://www-03.ibm.com/ibm/history/history/decade_1960.html IBM (date unknown) IBM Archives: 1970. Retrieved March 13, 2005 from http://www- 03.ibm.com/ibm/history/history/year_1970.html IBM (date unknown) IBM Archives: 7090 Data Processing System. Retrieved February 17, 2005 from http://www- 03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP7090.html Iowa State University (2004) John Vincent Antanasoff and the Birthplace of the Digital Computer Retrieved March 2, 2005 from http://www.cs.iastate.edu/jva/jva-archive.shtml Mainframe History: The Big (Mainframe) Computers (1986) Retrieved January 25, 2005 from http://icarus.brainerd.net/~kuck/history/mainfram.html Websites Bibliography: Schneiderman, Ron 1986 Computers: From Babbage to the Fifth Generation. New York: Grolier.
Mainframe Introduction. Last updated: July 12, 2004 History of Computing Project Retrieved January 25, 2005 from http://www.thocp.net/hardware/mainframe.htm Moye, William T. (January 1996) ENIAC: The Army-Sponsored Revolution Retrieved March 2, 2005 from http://ftp.arl.mil/~mike/comphist/96summary/index.html Wikipedia (January 2, 2005) Mainframe computer the free encyclopedia Retrieved January 24, 2005 from http://en.wikipedia.org/wiki/mainframe_computer