Some Remarks on a Large New Time-Sharing System

Butler Lampson


Citation: Internal memo, Berkeley Computer Corporation, September 1970.

Links: Abstract, Acrobat.

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During the last 18 months, the Berkeley Computer Corporation (BCC) has designed and constructed a large new multi-access system, the BCC Model 500. Both hardware and software for this system have been built from scratch, and the system is now operational. This presentation describes the characteristics of the Model 500 which we now see as important to its success. These may be classed under four general headings:

·         efficiency, obtained through specialized hardware

·         reliability, which depends on redundancy, error-checking and good protection mechanisms

·         modularity in both hardware and software

·         high-level language programming