Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of GraphSearch.
Concept
3B series computers
Summary
The 3B series computers are a line of minicomputers made between the late 1970s and 1993 by AT&T Computer Systems' Western Electric subsidiary, for use with the company's UNIX operating system. The line primarily consists of the models 3B20, 3B5, 3B15, 3B2, and 3B4000. The series is notable for controlling a series of electronic switching systems for telecommunication, for general computing purposes, and for serving as the historical software porting base for commercial UNIX.
The first 3B20D was installed in Fresno, California at Pacific Bell. Within two years, several hundred were in place throughout the Bell System. Some of the units came with "small, slow hard disks".
The general purpose family of 3B computer systems includes the 3B2, 3B5, 3B15, 3B20S, and 3B4000. They run the AT&T UNIX operating system and were named after the successful 3B20D High Availability processor.
In 1984, after regulatory constraints were lifted, AT&T introduced the 3B20D, 3B20S, 3B5, and 3B2 to the general computer market, a move that some commentators saw as an attempt to compete with IBM. In Europe, the 3B computers were distributed by Italian firm Olivetti, in which AT&T had a minority shareholding. After AT&T bought NCR Corporation, effective January 1992, the computers were marketed through NCR sales channels.
Having produced 70,000 units, the AT&T Oklahoma City plant stopped manufacturing 3B machines at the end of 1993, with the 3B20D to be the last units manufactured.
The original series of 3B computers includes the models 3B20C, 3B20D, 3B21D, and 3B21E.
These systems are 32-bit microprogrammed duplex (redundant) high availability processor units running a real-time operating system. They were first produced in the late 1970s at the WECo factory in Lisle, Illinois, for telecommunications applications including the 4ESS and 5ESS systems.
They use the Duplex Multi Environment Real Time (DMERT) operating system which was renamed UNIX-RTR (Real Time Reliable) in 1982.
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.