The AS/400
It opened the door to network computing for ordinary users and paved the way for the paperless office
A woman typing into a keyboard and a man with a clipboard work at an AS/400 CPU, in 1988

In 1988, offices ran on paper, the fax machine reigned, and networked computers were for stockbrokers and characters in science fiction. IBM’s Application System/400 family of servers and network adapters changed all that.

For the first time, small businesses, city governments and other medium-size enterprises could set up their own computer networks and connect them to workstations, printers, file servers and even other networks — all running four times faster than what was previously possible. The AS/400 line created the digital work environment we know today. “Paperless society, here we come,” Dave Fuller of PDA Software Services, a consulting company in Overland Park, Kansas, told IBM Rochester News after AS/400 launched. It was a bold prediction in 1988, but he was right.

With an eye toward succeeding the popular System/36 and System/38 platforms, IBM developed the AS/400 line around two priorities: high performance and ease of use. The goal was to allow small and medium-size firms to set up and administer their own networks without specialized training — a powerful and scalable system for the general public, not just for governments and scientific institutions. The line was technologically advanced, but it also revolutionized business. Its base processors, the B10 and B20, were compact and quiet, designed to operate unobtrusively within existing office environments. The AS/400 family could be blended with existing systems easily, which meant businesses could move forward without starting over.

The AS/400 family could be blended with existing systems easily, which meant businesses could move forward without starting over

The OS/400 operating system was at the heart of the AS/400. It ran on all models and was backward compatible with most System/36 and System/38 applications. In a business environment where many firms relied on software developed in house — often at considerable expense — such compatibility allowed firms to upgrade to AS/400 networks without having to replace existing software. This proved to be a major factor in AS/400’s success, establishing backward compatibility as a reliable strategy in the consumer computing market.

The user-friendliness of OS/400 also made the AS/400 line accessible to programmers, system administrators and ordinary office workers alike. AS/400 standardized displays, menus and other interfaces across all models — a principle of design that 21st-century users take for granted but OS/400 pioneered.

These accessible interfaces were paired with a command-line interface for power users that made AS/OS/400 systems capable of advanced performance. Most of all, the AS/400 line emphasized connectivity: the power to integrate workstations, printers, photocopiers and other peripherals, so that devices from ASCII terminals to rack servers could operate on the same system, using the same interface and language.

The AS/400’s connectivity distinguished the AS/400 line from anything else on the market and greatly expanded IBM’s user base to include ordinary customers without technical backgrounds. “The hardware was in operation two hours after delivery,” said Charles Cox of Haltom City, Texas. “Surprisingly quick!” AS/400 made powerful resources available to municipal users like Haltom City, bringing the benefits of cutting-edge computing to the general public.

The AS/400 line emphasized connectivity: the power to integrate workstations, printers, photocopiers and other peripherals
Dawn of the remote office

Conceiving of a scalable system of processors and network adaptors that was both easy to use and faster than anything else on the market was relatively straightforward. Realizing the vision was another matter — one that fell to IBM’s engineers. The AS/400 line was built on two core assets: the industry’s most powerful microchips and a fast token ring network, the system that allowed servers, computers and peripheral devices to communicate with one another by transmitting and holding chunks of data.

IBM became the first company to ship megabit memory chips in computers — a change that required retooling its production facility in Essex Junction, Vermont, from churning out industry-standard 4-inch and 6-inch silicon wafers to 8-inch versions. The AS/400 line marked a substantial bet on the success of a new product — but it paid off as the power of the new line became clear.

For small and medium-size firms, the chips in the AS/400 line represented a geometric increase in processing speed, RAM and storage capacity. At the high end, AS/400 could process up to 45,000 transactions per hour — a tenfold increase over System/36. This processing speed was coupled with superior network capabilities. Before AS/400, IBM’s token ring networks operated at 4 megabytes per second (Mbps). The new system ran at speeds up to 16 Mbps. This development allowed many more machines to operate on the same network. Combined with new adapters for fiber-optic systems, it also allowed AS/400 systems to connect with other local area networks — paving the way for interoffice digital communications.

Some 35 years ago, the AS/400 line laid the groundwork for today’s remote-work environments. When the line was released, Robert Fertig of Enterprise Information Systems, a market research company, called it “the most significant announcement since the personal computer.” Small and intermediate-size organizations could digitize their filing and phone systems, increasing the efficiency of law offices, insurance agencies, architectural firms — any businesses that kept records, coordinated teams or communicated across offices.

By providing products that were user-friendly and scalable, the AS/400 family also brought a new group of users into the digital age. Networked computing that had previously been the exclusive province of multinational corporations and public institutions became available to ordinary businesses.

For millions of people around the world, the AS/400 system was the first glimpse of the 21st-century office: a place where information moved in microseconds and commerce moved nearly as fast. For modern business, the future began in 1988.

AS/400 45,000 Transactions processed per hour 10x Increased in transaction speed over System/36 4x Increased in network operation speed per second
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