No abstract

Comprehensive maintenance software is required to meet the system reliability objective of less than an average of 2 minutes per year of outage from all causes. The function and interrelationship of the four basic maintenance programs (fault recognition and recovery, diagnosis, trouble location, and error analysis) are detailed here. Results of extensive laboratory testing and early field experience indicate that the maintenance objectives will be achieved despite the size and complexity of the 1A Processor.

The quality of service that will be delivered by the Voice Storage System (1A vss) is influenced by a number of diverse factors which are addressed in this paper. High intrinsic reliability is designed into the system at every level; it is built from system redundancies, defensive software strategies, hardware self‐checking, and manufacturing quality control. Good service also requires a complement of equipment which can adequately handle peak traffic loads; the sizing of this complement is the job of Office Engineering. Effective maintenance software will minimize, and in most cases obviate, the impact on service of circuit component failures. And finally, effective plans and test equipment are required to ascertain that a newly installed 1A vss properly performs its intended functions.