Patent · US Expired

Access control system for use in a digital computer system with object-based addressing and call and return operations

US4545012A · kind A · utility

11Cited by
5References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 1981
Grant dateOct 1, 1985
Priority date
Expiry dateMay 22, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F13/18
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An access control system for use in a digital computer system wherein the memory system is organized into objects, a data item is locatable by specifying an object, instructions are contained in procedures, and the operations performed by the system include a call operation for suspending an execution of a procedure and commencing another execution and a return operation for terminating an execution and resuming a suspended execution. The access control system associates each procedure with a domain, i.e., a set of objects accessible to the procedure. The access control system further includes a secure stack object which is accessible only to the access control system. When a call operation commences execution of a procedure which has a different domain, the access control system responds to the call operation by storing information required to return to the current domain in the secure stack. When a return operation resumes execution of a procedure which has a different domain, the access control system responds to the call operation by using the information in the secure stack to return to the previous domain.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.