This chapter presents IMS's past and discusses IMS as a strategic part of today's computing environment.
In This Chapter:
- "History of IMS: Beginnings at NASA"
- "Is IMS Still Strategic for Customers and IBM?" on page 4
History of IMS: Beginnings at NASA
IMS has been an important part of world wide computing since its inception.
On May 25, 1961, United States President John F. Kennedy challenged American industry to send an American man to the moon and return him safely to earth. The feat was to be accomplished before the end of the decade, as part of the Apollo program. American Rockwell won the bid to build the spacecraft for the Apollo program and, in 1965, they established a partnership with IBM to fulfill the requirement for an automated system to manage large bills of material for the construction of the spacecraft.
In 1966, 12 members of the IBM team, along with 10 members from American Rockwell and 3 members from Caterpillar Tractor, began to design and develop the system that was called Information Control System and Data Language/Interface (ICS/DL/I). During the design and development process, the IBM team was moved to Los Angeles and increased to 21 members. The IBM team completed and shipped the first release of ICS in 1967.
In April 1968, ICS was installed. The first "READY" message was displayed on an IBM 2740 typewriter terminal at the Rockwell Space Division at NASA in Downey, California, on August 14, 1968.
In 1969, ICS was renamed to Information Management System/360 (IMS/360) and became available to the IT world.
Since 1968, IMS:
- Helped NASA fulfill President Kennedy's dream.
- Started the database management system revolution.
- Continues to evolve to meet and exceed the data processing requirements demanded by today's businesses and governments.
IMS as a Database Management System
The IMS database management system (DBMS) introduced the idea that application code should be separate from the data. The point of separation was the Data Language/Interface (DL/I). IMS controls the access and recovery of the data. Application programs can still access and navigate through the data by using the DL/I standard callable interface.
This separation established a new paradigm for application programming. The application code could now focus on the manipulation of data without the complications and overhead associated with the access and recovery of data. This paradigm virtually eliminated the need for redundant copies of the data. Multiple applications could access and update a single instance of data, thus providing current data for each application. Online access to data also became easier because the application code was separated from data control.
IMS as a Transaction Manager
IBM developed an online component to ICS/DL/I to support data communication access to the databases. The DL/I callable interface was expanded to the online component of the product to enable data communication transparency to the application programs. A message queue function was created to maintain the integrity of data communication messages and to provide for scheduling of the application programs.
The online component to ICS/DL/I ultimately became the Data Communications (DC) function of IMS, which became the IMS Transaction Manager (IMS TM) in IMS Version 4.