Tymshare

History

Overview

Tymshare Inc was a diversified computer services business initially founded and headquartered in Palo Alto, CA and eventually based in Cupertino, CA. Tymshare was founded in 1965 to provide commercial computer services to engineering and scientific users in the San Francisco Bay area in the form of computer timesharing, a new and developing technology at the time. Although IBM and GE were experimenting with commercial application of computer timesharing in 1966 it was untested in the real world of markets, technology and profitability.

In its almost 20 years as a successful publicly traded enterprise Tymshare became an international company with locations in France, Canada, The UK, Germany, Japan and a number of other countries. Over time Tymshare added new revenue producing divisions involved in computer consulting, computer maintenance, financial transaction services, computer networks and computing services for the fuel and travel industries. Tymshare grew to over $300 million in annual sales ($750 million in 2016 dollars) with over 3500 employees. After over 18 years as a successful and independent entity it was sold in 1984 to McDonald Douglas Corporation. It was purchased as a supplement to its own existing computer timesharing and services business as well as contemplated future commercial network offerings. Subsequently over the next 20 years parts of Tymshare and its Tymnet network business were sold to British Telecom, Sprint and MCI. The last functioning part of the Tymnet network only ceased to operate in 2004, almost 20 years after the sale of Tymshare to McDonald Douglas Corporation.

Along the way through growth and expansion Tymshare pioneered many technology and business innovations to meet the challenges of its businesses and growth. Many of these innovations have become a part of other companies and whole segments of the computer industry for a variety of computing oriented uses.

Timeshared Computing and the idea to start a business (This history 1965-1970 was written in 1970 by Rebecca McNown, then an employee of Tymshare. Tenses are left as written in 1970)

Tymshare, Inc. is a California corporation with its first headquarters in Palo Alto. The company was formed to market timesharing computer services, Computer timesharing is a method by which many people may simultaneously, from their own locations pretty much wherever they may be. These many users use the same computer to solve their computational problems. The computer slices its processing time into a small interval for each user and then after a designated time, saves the state where its work is currently for an individual user and then moves to the next time slice for the next user, retrieves their state as last preserved and processes their work for another designated interval. By doing so over and over at an extremely fast pace each person is unaware that he is sharing the computer. To him, it appears that he alone is using it although in reality the computing and associated resources are shared.

Tymshare's customers may access one of the company's computers from their individual locations with a simple phone call. A customer leases or purchases a terminal, which may be a teletypewriter-like device or a cathode ray tube unit, and an acoustic coupler which connects the terminal and the computer via a standard telephone.

The primary advantages of time-sharing are instant availability of computing resources, remote access capabilities, access to a large variety of computing resources (languages, editors, compilers, software applications, data storage, etc) and finally its economy compared to dedicated in house computers. The customer is not required to lease, purchase, or maintain his own computer. Nor does he need to develop his own languages to run the computer. He uses the computer languages and applications programs developed and made accessible by the timesharing vendor.

Timesharing is a recent development in computer technology. The mid-1960's saw the birth of several companies specifically to market time-sharing services and the diversification of other companies to include such services in their repertoire. After these initial companies proved the practicality of timesharing, a virtual flood of time-sharing companies opened in the period from 1966 to 1968. The economic downturn of the late sixties and the stabilization of the time-sharing market have caused many of these time-sharing companies to go out of business or to merge with other companies.

Tymshare (in 1970) currently employs approximately 300 people and provides three basic types of service:

1. A general computational service providing the user with a variety of computer languages. The user develops his own programs with these languages. The languages offered by Tymshare are SUPER BASIC, SUPER FORTRAN, BATCH FORTRAN IV, FORTRAN II, BATCH FORTRAN, CAL, EDITOR, and EXECUTIVE.
2. A repertoire of applications programs, allowing customers to solve their computational problems without having to write programs. Applications programs are available in the fields of logic and continuous system simulation, statistics, electrical and structural engineering, and business.
3. Facility management, providing a customer with in-house computer equipment, plus the necessary software and operations personnel to maintain it. at a fixed monthly charge.

In addition to these services. Tymshare markets certain types of related computer equipment. selling computer terminals, including teletypewriters. cathode ray tube devices. and plotters. The company also sells acoustic couplers used to link terminal equipment to the computer via the telephone.

Founding and initial goals

Tymshare. Inc. is the fulfillment of a lifetime dream of its president, Thomas. J. O'Rourke. He had followed with interest the various university research projects which were developing time-sharing hardware and software. These projects, often joint efforts between the electrical engineering and computer science departments. included Project MAC at MIT, ATLAS at Cambridge University. and similar projects at the University of California at Berkeley and Dartmouth.

In addition, Mr. O'Rourke had possessed for some time the desire to found and direct his own company. In January, 1965, Mr. O'Rourke was the Western Regional Marketing Manager for General Electric with headquarters in Sunnyvale. An electrical engineer. he had been associated with GE for 17 years. During these years, the O'Rourke family had grown to eight members and the numerous relocation which are a part of management careers were becoming less and less palatable to them. The family wanted to settle permanently, preferably in California.

General Electric and Mr. O'Rourke came to a parting of the ways in May 1965. It seemed a perfect time to put into action his plans to form a time-sharing company. He and David Schmidt, a technical consultant at GE. formed a partnership, Tymshare Associates, in May, 1965,

Time-sharing was untested as a commercial venture. Both IBM and GE were experimenting in the field, but it was not a proven money maker. For this reason, the purpose of Tymshare Associates was to investigate the feasibility of selling time-sharing services to the scientific and engineering communities in the San Francisco Bay Area.

The headquarters of Tymshare Associates were located at 745 Distel Drive in Los Altos, California in August 1965. The secretarial work for the enterprise was done by the Camino Secretarial Service, operated by Mrs. Patricia D!Agati. Mrs. D'Agati was hired by Tymshare in April, 1966, as executive secretary to Mr. O'Rourke. She still holds that position and that of Personnel Administrator. (2)

Roger L. Mosher, partner in the 'Wilson, Mosher & Martin law firm in Palo Alto was named'the company attorney. He assisted in drawing up the company by-laws and now serves on the Board of Directors as Secretary. (2) Mr. O'Rourke and Mr. Schmidt made a thorough marketing survey and became convinced that time-sharing was indeed a marketable service. They planned to acquire a GE Model 225 computer and to modify it for time-sharing.The fruit of the Tymshare Associates partnership was a l0 page business plan for marketing a time-sharing service based on that machine. Their plan was to establish the company in the Bay Area and to serve the scientific community there. This proved to be a very shortsighted idea.

The two partners then began marching up and down Montgomery Street in San Francisco looking for backers. They were seeking initial financing in the amount of $250, 000. They found a sympathetic ear at the Bank of America's Small Business Enterprises Company. The SBEC operates under the auspices of the federal Small Business Investment Corporation especially to fund such small business ventures as Tymshare's.

In July. 1965, the Bank of America approved the loan and Tymshare was on its way to starting business. The computer had been ordered from General Electric. However; in August, 1965, GE turned down the order, ostensibly because of Tymshare's shaky credit rating. Other factors quite probably played a part, as General Electric was beginning to enter the time-sharing market in earnest. This forced Tymshare to renegotiate financing. This unexpected turn of events forced a reevaluation of the hardware to be used for time-sharing. Mr. O'Rourke and Mr. Schmidt took another hard look at the university projects and were most impressed by the ARPA project at the'University of California at Berkeley. This project, using a Scientific Data Systems 930 computer, seemed to be the most advanced and the most flexible.

Mr. O'Rourke and Mr. Schmidt then went to SDS. now Xerox Data Systems. with a proposal to extend th.e model 930·s capabilities by developing the model 940 computer for time-sharing. They knew that convincing SDS would not be an easy task. as Max Palevsky, President and founder of the company. had gone on record with his opinion that time-sharing was a flash-in-the-pan and would not last. But O'Rourke and Schmidt convinced Dan L. McGurk, then Manager of Marketing, and Art Rock, Chairman of the Board, that Palevsky was wrong. McGurk and Rock then sold Mr. Palevsky on the idea and SOS agreed to assume the project if Tymshare would restructure the Berkeley software, add disk file capability to the software, and sell four 940'5. Mr. O'Rourke agreed to all these conditions, relying on his past sales experience to carry out the third condition. In return, SDS promised Tymshare serial number 1 of the 940 series. Tymshare Associates then prepared a second business plan based on the SOS 940. This plan was submitted to the SBEC and was approved.

Mr; O'Rourke had done such a good job of selling the SBEC on the Tymshare venture that George Quist. then President of the SBEC, was persuaded to invest personally. He has served on the Board of Directors since the company's founding.

Mr. O'Rourke turned out to be correct in his evaluation of his ability to sell the 940. The four assigned to him were sold to Shell Oil Company and Stanford Research Institute in the Bay area and to two infant time-sharing corporations, Com-Share in Ann Arbor. Michigan. and Dial-Data, Inc.• in Newton, Massachusetts. Mr. O'Rourke was convinced that Tymshare would remain a West Coast company and had no qualms about encouraging the development of time-sharing companies in the east and mid west.

The next task facing Tymshare was to assemble a technical staff. The first member hired was Verne Van Vlear, a former systems analyst for General Electric and a recognized expert on time-sharing. Mr. Van Vlear had worked with Dave Schmidt at GE and had seen the Tymshare plan as it developed. During the fall of 1965, Van Vlear and Schmidt were in constant communication. Tymshare Associates sent Van Vlear to the Fall Joint Computer Conference in Las Vegas in November. 1966, and two weeks later Van Vlear joined Tymshare as a senior programmer. (5)

Another of the early employees' was Neil Sullivan who joined Tymshare in January, 1966. Previously employed by Control Data Corporation. he began working as a sales instructor. He is now one of the Senior Systems Analysts.

Ann Hardy. another systems programmer recognized in the Bay area, was lured away from Ll-Ie computer science department at the Lawrence Radiation Laboratory in Livermore. She joined Tymshare in February, 1966, and has since contributed significantly to the company's software effort as well as twi.ce becoming a mother. Her husband, Norm, is one of Tymshare's leading programmers and is manager of the Systems Programming staff. (2)

Tymshare Associates became Tymshare, Inc. in January, 1966. This was the culmination of seven months of tireless effort by Tymshare Associates. Mr. O'Rourke became President and Chairman of the Board of the new corporation. Mr. Schmidt became Executive Vice President and soon assumed the additional duties as General Manager of the Technical Division.

The name Tymshare was chosen because it reflected the type of business in which the company was engaged and because it was not capable of being shortened to a three-initial acronym. The founders, Mr. O'Rourke and Mr. Schmidt. designed the company's trademark, the hourglass. because of ite association with time.

Beginning operations

The first Berkeley software was delivered to Tymshare in March. 1966, and the systems programmers began redesigning it for commercial use. Mr. Van Vlear and Larry Barnes. the latter a graduate student at Berkeley. spent much of March and April at the SDS manufacturing plant in Santa Monica working on the computer before it was completely finished. (5)

A serious objection to the Berkeley software was that swapping of users in and out of core was being done on magnetic tape. Mr. Van Vlear and Mr. Barnes were attempting to implement a system whereby swapping would be done on the disk. Ann Hardy meanwhile, was designing a long range method by which swapping could be done on the RAD. the rapid access disk. (5)

Serial number 1 of the SDS 940 was delivered to Tymshare's computer center on East Meadow Drive in Palo Alto in May. 1966. The technical staff continued to put it through its paces. The system developed problems and much of the software was either rewritten or modified. (5)

Much of the modification of the early software was a joint effort between Tymshare and ComShare, working out of Tymshare's Los Altos office. Richard Crandall and two other ComShare programmers came to California during the spring of 1966 for this purpose, Mr. Crandall is now President of Com-Share. (2)

The first customers began using the Tymshare time-sharing system on an experimental. free basis in July. 1966. The maximum number of simultaneous users was eight. The system was demonstrated at the Fall Joint Computer Conference held in San Francisco in November. 1966, and was an overwhelming success. At this point, the company's backers began to apply pressure. So even though the system was not perfect, notices were sent to all users

that the service would be on a paying basis as of November 1, 1966. On November 1 and 2. the system was down, and it continued to be plagued with problems all month.

The sales force could not believe that Tymshare would send bills for such poor service that month. However, the statements did go out, and all but one customer paid immediately. The delinquent user paid after moderate prodding and continues to be a Tymshare customer. During this period of conversion to a commercial basis, an accounting department was established. Edward J. Field joined Tymshare in November, 1966. as Manager of Accounting. He was appointed Controller in February, 1968, and Treasurer in September, 1969.

Mr. O'Rourke took the bills and payments to the Bank of America in December, 1966. to prove that indeed people would pay for such a service. He then requested a second one-quarter million dollar loan for additional hardware and staff. The loan was granted.

The Bay Area market'for time-sharing services was expanding. The new company now had 14 employees, including a small sales staff headed by John Jerrehian as Sales Manager. Mr. Jerrehian was a former GE manager.

An even more lucrative market was identified in the Los Angeles metropolitan area. An office was opened in Inglewood, and computer #2 was .leased in August, 1966. The computer was installed in the Irglewood computer center in February, 1967. Business was so good that another computer was installed in southern California on December 22, 1967.

The general structure of the company was somewhat stabilized about this same time, Ray Wakeman was hired in August, 1966, as Vice President and General Manager of the Soutilern California Division. He had been employed as Manager of Customer Relations for SDS. John Jerrehian was named Vice President and General Manager of the Northern California Division.

During the summer of 1967. the Board of Directors and the officers of the company realized that Tymshare possessed the potential to become a nationwide corporation. The area they selected for the next expansion was the New York/New Jersey metropolitan area. Mr. O'Rourke began to solicit financial backing for this expansion. He haunted Wall Street until he found a willing listener in Tony Lamport of Burnham and Company. Through the efforts of Mr. Lamport and his associates, a million dollar private placement of Tymshare stock was effected, and Tymshare proceeded with its expansion plans. Mr. Lamport is now a Director of Tymshare.

The Eastern Division was established with an office in Englewood Cliffs~ New Jersey. The eastern customers were served by multiplex lines from the Palo Alto computer center until computer #4 was installed in New Jersey on March 29, 1968. The Eastern Division did not develop as expected. To get things moving again, Mr. O'Rourke himself went east for two and one half months during the summer of 1968. He returned in August. having appointed John Jerrehian as temporary manager of the Eastern Division. Ron Braniff, Sales·Manager of the Northern California Division was appointed Acting Division Manager of the Northern California Division and in this capacity. worked closely with Mr. O'Rourke, In February 1969. Mr. Braniff was promoted to Eastern Division Manager. Mr. Jerrehian then returned to his former position as Division Manager of the Northern California Division.

Another personnel addition in 1968 was the employment of Alden Heintz in August as Director of Marketing. He was named Vice President of Marketing in September~ 1969, and Vice President for Corporate Development in June, 1970.

New offices continued to open. By the end of 1968~ Tymshare had grown to 138 employees, five computers. and seven district sales offices. Los Altos and Seattle comprised the Northwestern Division, formerly the Northern California Division. The three district offices in the Southwestern Division (formerly the Southern California Division) were in Inglewood, California; Newport Beach, California; and in Dallas, Texas. Englewood Cliffs and Washington, D. C. served the Eastern Division.

The office at Distel Drive was not large enough to house the four groups operating from it: Corporate, Northwestern Division, Palo Alto District, and the Technical Division. The first to go was the Technical Division, moving to an office at 925 East Meadow Drive in Palo Alto in March, 1968.

Three more offices opened in 1969. They were in San Francisco, Boston, and Darien, Connecticut. Five more computers were installed. There were now two in each of the three divisions and four at the new computer center in Cupertino. Plans were being made to bring all Tymshare computers to the Cupertino computer center.

Another important change of address made in 1969 was the move of the Corporate offices to the Palo Alto Office Center, 525 University Avenue, Palo Alto, California. The offices have expanded and now occupy one and one half floors of this building. The Technical Division programmers moved again in April, 1970. This move was to Bubb Road in Cupertino~ bringing the programming and operations staff together in a three building complex in the West Valley Industrial Park.

Dr. Helmut Sassenfeld was named General Manager of the Technical Division in September. 1969, to replace David Schmidt who resigned in June, 1969. (See Page 19.) Tymshare currently has twelve district offices. the newest ones opening in Chicago and Houston in the early months of 1970.

Early success

Tymshare has proved itself a viable institution in an industry which had a low survival rate of new companies. A total of two million dollars of financing was obtained in another private placement in December, 1968. with large amounts being invested by such institutions as Morgan Guaranty Bank, Fireman!s Fund, J. H. Whitney and Company. and the Ford Foundation.

Through these past four years, Tymshare had many offers to be acquired or to acquire other companies. Each of these offers was explored, but none was accepted. In late 1969. however. Dial-Data, Inc., of Newton, Massachusetts, and Tymshare, Inc. agreed to a merger of their two companies. The new company was called Tymshare East, Inc. , a wholly -owned subsidiary of Tymshare, Inc.

Lewis C. Clapp, president of Dial-Data, Inc., and Mr. O'Rourke had been friends of long standing. Mr. Clapp had founded Dial-Data in March 1965. Mr. Clapp became Executive Vice President and a Director of Tymshare, Inc. Because Dial-Data had also based its service on the SDS 940 and at the time of the acquisition had five such computers, Tymshare increased its computer capacity to 15. Another advantage to the merger was the acquisition of Dial-Data's excellent programming staff and its electronics applications programs. By combining the efforts of the two sales staffs and moving the computers to Cupertino, the new company became profitable within four months of the merger.

In 1969, Tymshare participated with two French businesses in a joint venture. The new company, CEGOS-Tymshare, is a collaboration among CEGOS-Informatique of Paris, Credit Lyonnais, and Tymshare. Tymshare currently owns 20 percent of the capital stock of the new company. CEGOS-Informatique, a major European management consulting firm, operates several in-house computer systems. Credit Lyonnais is France!s second largest bank. CEGOS-Tymshare, headquartered in Paris, will offer time-sharing service throughout France. The service will be similar to that marketed throughout the United States. Several Tymshare employees have been sent to Paris to assist in the operation of the enterprise.

A second foreign venture, Tymshare Canada Ltd.• was formed in late 1£)69 and will begin commercial operation in the second half of 1970. Tymshare is joining with EDP Centres Limited in the formation of this Canadian corporation of which Tyrnshare owns 40 percent.

In the computer service industry, it is important to keep pace with the hardware developments within it. A product which serves well one year may become obsolete the next year by new inventions and discoveries. A continuing effort has been made at Tymshare in the area of hardware development. An early example of hardware development was the design of an acoustic coupler as an aid for the sales staff in the demonstration of the Tymshare service. The coupler was a brainchild of Mr. Schmidt and was built by a small firm, Communications Contact. This firm, located in the same building as Tymshare on Distel Drive, was composed of Nels Winkless, Paul Honore, and Terry Wilson. (2)

Tymshare has worked hard to develop the finest communications system in the industry. The first computer set up had communications lines radiating from it. These lines were able to serve only customers in the local area. (1)

The next improvement was the addition of multiplexers to the system. A multiplexer is a device which enables many signals to be sent simultaneously over the same wire or transmission medium. Thus one wire could transmit information fr.-om many customers to a single computer and vice versa. (I) The next innovation was to use a small computer to perform the multiplexer function. The advantage to this method was that the transmission error rate could be reduced to 1 in 100,000. The company investigated several satellite computers and chose the Varian 620i. Using software and hardware modifications developed by Tymshare, this computer answers the phone and links the caller to the central processing computer. Used in this way. the Varian 620i is called a TYMSAT. (1) The TYMSAT capability was then ex.tended so that it replaced the communications termination equipment (eTE) used to link customer calls to the computer. This upgrading reduced the error rate to 1 in four billion. (!!) The future of the Tymshare communications system is the TYMNET. a veritable network of TYMSATs. TYMNET will allow error free international transmission of data. alternate routing in emergencies, and load leveling among all Tymshare computers. (1)

The Director of Telecommunications for Tymshare is Max Beere who joined the company in April. 1969. A former employee of Bell Telephone Company, he is responsible for the design of TYMNET and for handling communications with various utility companies. LaRoy Tymes is responsible for the programming necessary to effect the TYMNET network. He and Mr. Beere work closely together to assure good service for Tymshare customers.

Refinements and development to make the business scale

Tymshare's time-sharing users store data, programs. and other information on magnetic disks. These are storage devices in which data is recorded on the magnetized surface of a rotating disk. The disks are arranged in an array structure with associated heads for reading and writing information on the disk.

All available disk ·storage devices have a finite capacity. Disk storage began to be a problem for Tymshare as the demand for disk space exceeded the available space. Therefore new disks had to be investigated. The IBM 2314 disk, with a capacity of 200 million characters was chosen to replace. gradually, the original 50 million character Data Products disk.

Another area in which Tymshare is currently improving its equipment is the computers themselves. The XDS 940 was a good machine in 1966, but later development in this industry has resulted in larger and faster computers.

Consideration was given to a plan whereby Tymshare would develop and build its own ideal time-sharing computer. David Schmidt, then Executive Vice President, was especially interested in this project. He could not, however, sell the Board of-Directors and resigned from Tymshare in June, 1969, forming his own company to manufacture this sophisticated computer. Mr. Schmidt IS new company is Multi-Access Systems of California, Inc. The computer is currently under development.

Tymshare continued to investigate other third-generation computers. A Digital Equipment Corporation PDP-10 was obtained on a trial basis. At the time of the merger, Dial-Data had an XDS Sigma 7 on order. It was delivered to the Cupertino computer center in March, 1970.

A period of evaluation of the two computers began. Because the PDP-10 and the Sigma 7 were very similar in capability, the ultimate decision was largely a financial one. The PDP-10 was on a purchase-only basis, and the Sigma 7 could be leased. Because of the difficulties in obtaining additional funds in the spring and summer of 1970, the decision was made to go with the Sigma 7. This decision required the least capital outlay. Sigma 7!s were placed on order for delivery in 1970 and 1971. The PDP-IO programmers joined the Sigma 7 programmers to complete the programming of the Sigma '7 in preparation for the first commercial offering of Sigma 7 service in late 1970.

Tymshare has been a very successful company since its inception. Gross sales have grown from one million dollars in 1967 to 2.6 million dollars in 1968 and 6.4 million in 1969. The projected figures for 1970 are 12 million dollars. Mr. O'Rourke bases his company's success on service. As he puts it, "We are a service bureau; therefore we have a responsibility to provide service." He also believes that a strong marketing staff is

important to a thriving time -sharing company, and he feels that Tymshare's marketing force is the best in the industry. He cites as other key factors in Tymshare's success the outstanding programming, operations, and hardware development staffs which the company has assembled. The programmers have developed outstanding programming languages .and applications programs. The operations staff efficiently maintain the company's computers.

Tymshare points with pride to the documentation it produces to support its languages and applications programs. This documentation is supplemented by free classes conducted by Tymshare instructors.

From its beginning. Tymshare's programming and marketing impetus has been directed toward the scientific and engineering community. Through the capable efforts of the business language programmers, Tymshare's service has diversified into the business world also.

With time-sharing estimated to be the fastest-growing segment of the computer industry, the future certainly looks challenging for Tymshare.

Further sections to be completed

• Challenges, competitors and innovations
• Growth and changes in direction
• Diversification
• Tymnet expansion and as an independent business
• Plans to deal with the advent of mini computers and personal computers in the marketplace
• Sale of the company and subsequent sales of segments of the business
• Legacy of Tymshare technologies and business process

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Below are previous entries made to this article now intended to be edited or replaced (these were added earlier primarily to expand on the Tymnet portion of Tymshare's business and will be placed in a new section and edited to improve the order and flow of the Tymshare history)

The computing platforms included the SDS 940, XDS 940 (Tymcom-IX), XDS Sigma 7, DEC PDP-10 models KA, KI, KL and KS (Tymcom-X/XX, Tenex, August, Tops-20), XKL Toad-1, IBM 360 & 370 (VM, MVS, GNOSIS) servers.

Divisions:

• INSD — Information Services Division
• STD — Systems Technology Division
• DND — Data Networks Division

In 1984 Tymshare was acquired by McDonnell Douglas, restructured, split up and portions were resold, spun off, and merged with other companies from 1984 through 2004 when most of its legacy network was finally shut down. Islands of its network technology continued as part of EDI, at least into 2008.

McDonnell Douglas was acquired by Boeing. Consequently, rights to use technology developed by Tymshare are currently held by Boeing, British Telecom (BT), Verizon Communications, and AT&T Inc. due to the acquisitions and mergers from 1984 through 2005.

Development of Tymnet

In 1968, in order to help meet the need for an expanding number of customers located around the U.S. and eventually the world Ann and Norm Hardy, Bill Frantz, Joe Rinde, and LaRoy Tymes developed the idea of using remote sites with minicomputers to allow users to communicate with the computers and associated services. The minicomputers would serve as the network's nodes, running a program called a "Supervisor" to route data. In November 1971, the first Tymnet Supervisor program became operational. Written in assembly code by LaRoy Tymes for the SDS 940, with architectural design contributions from Norman Hardy, the "Supervisor" was the beginning of the Tymnet network. The Varian 620i was also used for the TYMNET nodes. During those first years, Tymshare and its direct customers were the network's only users.

It soon became apparent that the SDS 940 could not keep up with demands placed on it by the rapid growth of the network. In 1972, Joseph Rinde joined the Tymnet group and began porting the Supervisor code to the 32-bit Interdata 7/32, as the 8/32 was not yet ready. In 1973, the 8/32 became available, but the performance was disappointing and a crash-effort was made to develop a machine that could run Rinde's Supervisor.

In the beginning of the 1970s Tymshare became available in Europe through Cegos-Tymshare, a joint venture with Credit Lyonnais. It extended to Brussels in 1973. An operation in the United Kingdom started in 1974.

In 1974, a second, more efficient version of the Supervisor software became operational. The new Tymnet "Engine" software was used on both the Supervisor machines and on the nodes.

After the migration to Interdata, they started developing Tymnet on the PDP-10. Tymshare sold a copy of the Tymnet network software to TRW, who created their own private network, TRWNET.

In the 1970s, Tymshare, which had used Digital Equipment's operating system TOPS-10 for its PDP-10s, began independent work on the OS for their systems, called it TYMCOM-X, and implemented a file system that supported random access, paging with working sets, and spawnable processes. The OS work was done by a group of eight people: Bill Weiher, Vance Socci, Allen Ginzburg, Karen Kolling, Art Atkinson, Gary Morgenthaler (founder of the company that produced INGRES), Todd Corenson and Murray Bowles. Most Tymnet development was then done on TYMCOM-X. Also in the 1970s, Tymshare acquired the Augmentation Research Center from SRI International.

Tymes and Rinde then developed Tymnet II. Tymnet II ran in parallel with the original network, which continued to run on the Varian machines until it was phased out over a period of several years. Tymnet II's different method of constructing virtual circuits allowed for much better scalability.

Tymnet, Inc. spun off

In about 1979, Tymnet Inc. was spun off from Tymshare Inc. to continue administration and operation of the network. The network continued to grow, and customers who owned their own host computers and wanted access to them from remote sites became interested in connecting their computers to the network. This led to the foundation of Tymnet as a wholly owned subsidiary of Tymshare to run a public network as a common carrier within the United States. This allowed users to connect their host computers and terminals to the network, and use the computers from remote sites or sell time on their computers to other users of the network, with Tymnet charging them for the use of the network.

Tymshare sold to McDonnell Douglas

McDonnell Douglas Tymshare

In 1984 Tymnet was bought by the McDonnell Douglas Corporation as part of the acquisition of Tymshare. The company was renamed McDonnell Douglas Tymshare, and began a major reorganization. A year later, McDonnell Douglas (MD) split Tymshare into several separate operating companies: MD Network Systems Company, MD Field Service Company, MD RCS, MD "xxx" and many more. (This is sometimes referred to the Alphabet Soup phase of the company). By then, Tymnet had outlived its parent company, Tymshare.

McDonnell Douglas acquired Microdata and created McDonnell Douglas Information Systems Group (MDISC), expecting to turn Microdata's desktop and server systems along with Tymshare's servers and Tymnet data network into a major player in the Information Services market. Microdata's systems were integrated into many parts of McDonnell Douglas, but Tymnet never was. MDC really did not seem to understand the telecommunications market. After five years, peace was breaking out in many places in the world and McDonnell Douglas sold off MDNSC and MDFSC at a profit for much needed cash.

MDC Network Systems Company sold to British Telecom

BT Tymnet, BT North America, BTNA

On July 30, 1989, it was announced that British Telecom was purchasing McDonnell Douglas Network Systems Company, and McDonnell Douglas Field Service Company was being spun off as a start-up called NovaDyne. McDonnell Douglas was later acquired by Boeing. British Telecom (BT) wanted to expand and the acquisition of Tymnet which was already a worldwide data network helped to achieve that goal. On November 17, 1989 MDNSC officially became BT Tymnet with its headquarters in San Jose, California. BT brought with it the idea of continuous development with teams in America, Europe, and Asia-pacific all working together on the same projects. BT renamed the Tymnet services, Global Network Services (GNS).

British Telecom brought new life to the company with development of hardware and software for the Tymnet data network using contacts BT already had with telecommunication hardware vendors. There was a trial of "next-generation" nodes scattered throughout the network, called "TURBO engine nodes" based on the Motorola 68000 family. In the mid to late 1980s, serious node-code development was migrated from the PDP-10s to UNIX. Sun-3 (based on the Motorola 68000) and later Sun-4 (SPARC based) workstations and servers were purchased from Sun Microsystems, though the majority of PDP-10s were still around in the early 1990s for legacy code, as well as documentation storage. Eventually, all of the code development sources were on the Sun-4s, and the development tools (NAD, etc.) had been ported to SunOS.

Another project begun a few months before the BT purchase was to migrate the Tymnet code repository from the PDP-10s to Sun systems. The new servers were dubbed the Code Generation Systems or CGS. They were initially six Sun-3/280 servers upgraded eventually to two Sun-4/690 servers for redundancy. A second pair of servers for catastrophic failover was also installed in Malvern, Pennsylvania and later moved to Norristown, Pennsylvania as part of later site consolidation efforts. After the migration, these servers managed source code and binary images for more than 6600 nodes and 38,000 customer interfaces worldwide.

Tymnet was still growing, and at several times reached its peak capacity when some of its customers held network intensive events. One of these of note was a live, on-line presentation and chat on America On-Line (AOL) with Michael Jackson. Tymnet usage statistics showed AOL's call capacity was greater than its maximum volume for the duration of the event.

BTNA sold/split into MCI, Concert, and BT

MCI, NewCo, Concert

In 1993 BT and MCI Communications (MCI) negotiated what they called the "Deal of the Century", where MCI would take ownership of the U.S.-based portions of Tymnet and they would create a joint venture called "Concert". (The joint venture was called "NewCo" for more than a year while they decided on a name). Concert was also aligned with another acquisition of BT, called Synchordia which was headquartered in Atlanta, Georgia. Tymnet was then referred to as The Packet network, the BT/MCI network and Concert Packet-switching Services (CPS). At first, MCI only wanted to use the points of presence (POPs) that Tymnet had, because there were locations in over 150 cities in the United States, giving MCI more locations from which to provide local service. As MCI cut away at Tymnet, expecting it to die, it became a cash cow that just wouldn't go away.

In May 1994, there were still three DEC KL-10s under TYMCOM-X. At this time, the network had approximately 5000 nodes in 30 foreign countries. A variety of protocols can be run over a single packet-switching-network, and Tymnet's most-used protocols were X.25, asynchronous terminal and host (ATI/AHI), and SNA.

BT and Concert also continued to develop the network, and after the failure of the "Turbo nodes" to take off, decided to have an outside company add Tymnet protocols to existing hardware used in their frame relay network. Telematics International developed a subset of the Tymnet protocols to run on their ACP/PCP nodes. The Telematics nodes were connected in a mesh network (every node logically connected to every other node) via frame-relay and appeared to Tymnet as super-nodes that were directly connected to as many as 44 other super-nodes interconnecting most of Europe, Asia and the Americas as a high speed data network.

MCI took a different direction and sought to migrate the network protocols to run over TCP/IP and use SPARC technology. The supervisor technology was rewritten in C to run as standard UNIX applications under Solaris. Funding for this project was at a minimum but the Tymnet engineers believed it was a superior method and proceeded anyway.

Times were changing and the Internet and World Wide Web were becoming a practical and even important part of corporate and personal life. Tymnet technology needed improvements to keep pace with TCP/IP and other internet protocols. Both BT and MCI decided not to compete with the Internet, but to convert their customer base to IP-based networks and technologies. However, the Tymnet network was still bringing in considerable cash — in some cases more than current IP based services — so both BT and MCI needed to keep their customers happy.

MCI, MCI Worldcom, Worldcom vs. BT, Concert

In 1997 talks were underway for BT to acquire MCI. The deal fell through, and in September, 1998 MCI was acquired by WorldCom after they made a better offer for the company. Actually, the WorldCom offer was nearly identical to the BT offer, but where BT planned to buy out MCI shares of stock, WorldCom offered a stock-swap, which was more attractive to the stockholders. WorldCom took control in September 1998 and dissolved the BT/MCI alliance as of October 15, 1998.

Concert's headquarters in Reston, Virginia

With the alliance gone, BT and MCI Worldcom began the process of unraveling and separating their extensive voice and data communications systems.

Concert created Project Leonardo to separate the BT and MCI Worldcom voice and data networks. At times over the next five years, advancements were made or stalled due to BT and MCI management negotiating and renegotiating the terms of their contractual obligations to each other made during the alliance. At times, things came to a standstill, or decisions made were reversed, and some reversed again at a later time. Parts of the project were to migrate customers from X.25 to IP based networks, while others created a duplicate set of services so that both Concert and MCI could separately continue to run and manage their own portions of the network. Accounting data for network usage was also shared by the two companies and had to be separated before clients could be billed properly.

Concert and BT+AT&T's headquarters in Atlanta, Georgia

In 2000 BT then went searching for another alliance, and created a new Concert alliance between BT and AT&T, moving the headquarters to Atlanta, Georgia. This alliance did not help the negotiations between BT and MCI Worldcom as their partners from MCI and AT&T were corporate enemies. For Tymnet, the data network portion of the split, and the "CPS Leonardo" project, the split was never fully realized. Instead, MCI Worldcom completed their migration of services from Tymnet to IP based services in March 2003 and disconnected their supervisor nodes and their portion of the network on March 31, 2003. BT continued to run the network using their own supervisor and other utility nodes until February 2004 when their last customer was able to move all of its customers to other access services. BT and AT&T dissolved their Concert alliance on September 30, 2003 and the remaining BT assets were combined with BTNA assets into BT Americas, Inc. Sometime in early March 2004, without ceremony, BT Americas disconnected the last two remaining Tymnet supervisors from the network, effectively shutting it down.

MCI Worldcom still had a profitable segment of its business based on EDI technology. This technology used Tymnet to interface between Tandem computers using a non-standard x.25 interface and a high speed bi-synch modem used by the EDI customers. Prior to shutting down the MCI/Worldcom portion of Tymnet, they adapted the Tymnet Engine node code to permit internal connections between the x.25 interface and the high-speed modem interface without the aid of the Tymnet Supervisor. Once this was tested and deployed, they were able to shut down the rest of the MCI/Worldcom portion of Tymnet and continue to support their EDI customers. These "islands" of tymnet were still running 5 years later in 2008.

Worldcom bankruptcy

Worldcom executives were involved in a financial scandal resulting in the CEO, Bernie Ebbers, to be ousted and later charged with violations of federal statutes. This scandal sent the stock price down to 10 cents per share, and Worldcom filed for bankruptcy. It emerged from bankruptcy renamed as MCI several months later.

AT&T sold to SBC

On January 31, 2005, SBC Communications (SBC) announced that it would purchase AT&T Corp. for more than $16 billion. Shortly thereafter, the SBC name was changed to AT&T Inc. to distinguish itself from the original AT&T Corp.

MCI sold to Verizon

On February 14, 2005, Verizon agreed to acquire MCI, formerly WorldCom, after SBC agreed to acquire AT&T Corp. just a few weeks earlier.

Verizon was formed in 2000 when Bell Atlantic, one of the Regional Bell Operating Companies, merged with GTE. Prior to its transformation into Verizon, Bell Atlantic had merged with another Regional Bell Operating Company, NYNEX, in 1997

Tymshare EXEC

EXEC was the users access to the operating system. Depending on the privileges granted to the user there was a set of commands to perform various operating system tasks and to check the status of various system resources and states. Users with proper status could assign status to users assigned to them as well as establish log in privileges. A user could log in and out of user accounts, check account usage to date as well as other statistics pertaining to the resources available to them. There was both a user guide consisting of instructions on how to use EXEC and an INSTANT Series which was a small card format summary of commands for easy access.

Tymshare EDITOR

EDITOR was a proprietary text editor operated in line mode. Any text could be entered or modified here and saved to a named file kept on the user's disk area. Examples of its use are computer program source code, data, or text. The EDITOR made extensive use of control characters to speed the entry and editing of the text such as control, find next, delete, insert and so on. It was possible to write programs for SUPER BASIC and SUPER FORTRAN in EDITOR but without the benefit of the line compiling in those languages which served as a line by line check when entered directly in the language. Instead when an EDITOR file was submitted in the language the entire body of code was scanned for errors and highlighted. There was both a user guide consisting of instructions on how to use EDITOR and an INSTANT Series which was a small card format summary of commands for easy access.

Tymshare SUPER BASIC

Tymshare SUPER BASIC was a compile and go implementation of a variant of the BASIC programming language for the Scientific Data Systems SDS 940 time-sharing computer system, commercialized by Tymshare around 1968. The built in capability for real time entry of code in Super Basic provided immediate syntax error feedback due to the line compilation nature of Super Basic. Thus when you had completed writing whatever lines of code you required you were able to execute (or Run) the program without first compiling and with the assurance that there were not remaining syntax errors. Which is not to say there were no bugs in the program! There was both a user guide consisting of instructions on how to use SUPER BASIC and an INSTANT Series which was a small card format summary of commands for easy access.

Tymshare SUPER Fortran

Tymshare SUPER Fortran was a compile and go implementation of Fortran.