Proportional hazards modelling in the analysis of computer systems reliability

Abstract The analysis of the reliability of computer systems poses a number of complex problems. With the advent of VLSI and the diversity of usages the modelling of computer reliability has become far from straightforward. The cost of computer breakdown includes elements for loss of usage, and the cost of repair. To minimise the costs it is essential that computers are as reliable as possible. To achieve reliable desings suitable modelling of reliability has to be undertaken. Proportional Hazards Modelling (PHM) is an efficient technique which can identify the effects of the various explanatory variables which may be associated with variations in the times between faults on a computer system. In this paper we apply PHM to the analysis of fault data on a PCB set from an ICL product.