In developing the 5ESS™ switching system, a digital switch with distributed control, major emphasis has been placed on reliability, quality of service to the customer, and efficiency of the human interface for the telephone operating companies. To achieve a high-reliability design for this system, a robust hardware/software architecture has been developed with emphasis on a net working approach to functional maintenance organization. Building on this approach, a highly effective set of capabilities is provided for the detection and sectionalization of errors, and for recovery from software and hardware faults. Complete diagnostic aids are available, and flexible video display terminals provide an efficient and attractive means for telephone operating company personnel to interface to the system. Further, a wide range of automated, as well as manual, trunk and line test features are integrated into the system design; and interfaces to both local work stations and operational support systems provide a variety of options for efficient maintenance operation.

No abstract

No abstract

System software provided with the 1A Processor simplifies the task of using input/output devices, manages a portion of system time and memory resources, provides control over program interfaces, and provides an interactive facility that permits examination of system behavior. The impact of this software has been to simplify initial development of switching systems using the 1A Processor, to facilitate software maintenance, and to provide flexibility in adding system features. This article describes the capability and organization of the 1A Processor control, administrative, and utility software.