Safeguard data-processing system: The data-processing system performance requirements in retrospect

The Data-Processing System Performance Requirements (DPSPRs) specify the required performance to be provided by the SAFEGUARD system software. They were developed primarily by one systems engineering department at Bell Laboratories. Their objective was to specify the required functional performance in sufficient detail to permit software development. The DPSPRs evolved from similar documentation that was developed for systems prior to SAFEGUARD. Their history, development, use, and document control system are described. Suggested improvements are also discussed.