Happy 100th Birthday to IBM!
It is a small wonder that this June 2011, IBM is celebrating its ‘one hundred years’ of existence, nay, excellence. This, indeed, an achievement for a company that helped to establish technology over the years and stands out at the forefront of IT business today.
At this juncture a recapitulation of the history of IBM Mainframe is worth looking in to. The journey through the history of mainframes is exciting as it involves several twists and turns. Clearly, ruling out its extinction, IBM now stands with 90% of the mainframe market share over these years. In a time when mainframes are serving as the backbone of many large-scale business sectors like banking, finance, insurance etc with their imperative features of reliability, availability, security and serviceability, IBM stands committed and IBM mainframes continue to evolve.
IBM’s mainframe evolution can be generally categorized as:
1. First generation,
2. Second generation,
3. Third generation , and
4. The current Z-series
First generation Mainframes (1952- 1956)
IBM started development of large-scale computers in 1952, with the introduction of IBM 701, the first electronic data processing system. This was a vacuum tube machine, with an internal electronic memory to store programs. Designed for accounting & data processing, these systems were intended to serve typical small businesses. During the next few years, IBM developed even faster and more versatile vacuum tube machines. IBM 702, 704, 705, 650(most popular), RAMAC etc established the dominance of IBM in electronic data processing. On the other side, these systems were dissimilar in architecture, leading to integration challenges.
Second generation Mainframes (1958- 1964)
The Mid 1950 has witnessed the introduction of transistor-based mainframes. Compared to vacuum tube components transistors were small, reliable and less heat dissipating. With the machine 1401 IBM represented a much advanced mainframe model with features including high-speed card punching & reading, magnetic tape input & output, high speed printing, stored program, and arithmetic & logical ability. IBM 1440 of 1962 was a low cost system offering the benefits of a business information system. In the same year, IBM introduced 7094 for large-scale scientific computation. This system involves expanded functions of double precision floating-point operation and seven index registers. The need for general-purpose computers with architecture, compatible for both scientific and commercial usage led to the development of third generation systems.
Third generation Mainframes (1960- 1970’s)
In 1964, IBM transformed the course of computing history with its third generation mainframe IBM System/360. This was the first general purpose mainframe model compatible for both commercial and scientific usage. The launching marked a milestone in the history of mainframes. Solid Logic Technology-SLT (a new method for packaging electronic circuitry) based System 360 revolutionized the idea of unlimited storage with its central memory capacity (8,000 to 524,000 characters). The IBM System/360’s hardware included one main storage, 1-2 CPU’s, 1-7 channels, control units and devices. With the System 360, IBM started to rule business processing. IBM in System/360 utilized the concept of a single operating system OS/360 spanning an entire system. Other OS used in S/360 were Disk Operating System/360 (DOS/360), TOS, BPS and ACP.. This architecture also fulfilled requirements of handling very large amounts of storage in various data formats, high I/O rates with standard interfaces, scalability etc. IBM S/360’s systems also have a share in Apollo 11’s successful space mission of 1969. With improvised architectures and features, rest of 1960 has witnessed the market release of other versions of System/360.
1970 IBM released system/370 in 1970, with a compatible upgrade from system/360. The model 145 of System/370 was the first computer completely integrated monolithic memory (circuits in which all of the same elements – resistors, capacitors and diodes – are fabricated on a single slice of silicon) and 128-bit bipolar chips. Later in 1972, IBM introduced System 370 with virtual storage supported by VM/370 OS. Mature models of System 370, system370 with enterprise system architecture and quite a few other compatible models released later in 1980’s.
The 1980’s witnessed arrival of a new computing model called Distributed Computing models . Compared to mainframe systems, the distributed computing models appeared to be more economical. With increasing popularity of these models, some of the major mainframe players started to depart from the market. In early 90’s, industry observers even predicted the impending death of mainframes in near future. However, IBM continued to invest and research more on mainframes stressing on new technology core and bringing down the cost. With the introduction of 3081 processor, IBM brought in two-fold increase in internal performance from the existing mainframe processor 3033. Thermal conduction modules that significantly reduced power, cooling and space requirements also came in this period.
By 1990, IBM rolled out System /390 with Enterprise System Architecture. New processor based on CMOS was introduced into the mainframe environment. IBM got industry attention by announcing UNIX on IBM Mainframe in 1994. With that, Unix System Services became an integral part of the OS/390. Mid nineties marked the period of resurgence for IBM Mainframe. IBM came up with extended models of S/390 with S/390 Parallel Transaction Server (1994), system 390 Generation 5 servers (1998), system/390 Generation 6 server with copper chip technology (1999). Yet another major step in mainframe history came by the decision to consolidate IBM Mainframe with open source operating system Linux in 1999.
IBM added feather to its crown with Z Series e-Server in the millennium 2000 onwards, lets slice and dice the IBM Z series in our next session of “50 Plus Years of IBM Mainframe – A Recap. An IBM e-Server with e-business as core function with 64 bit operating system.
nandhakumars 