Learn in the textbookService Maintenance and Continual Improvement
DefinitionService availability management (サービス可用性管理) is the management activity that keeps a service usable whenever users want it, at the agreed level.
ExplanationAvailability is measured with figures such as the availability rate, the share of the committed service hours during which the service could actually be used. The rate goes up as the mean operating time from the end of one repair to the next failure (MTBF) gets longer, and as the mean time from a failure to the end of its repair (MTTR) gets shorter. Availability management keeps watch on these values and, when they look likely to drop below target, takes steps such as adding redundant equipment or revising maintenance.
AnalogyIt is like a bus company that cuts down on breakdowns and keeps spare buses ready to send out at once, so its routes run on schedule.
Memory hookThe Japanese 可用 reads as "fit for use," that is, in a usable state. The English availability likewise means being at hand and ready to use.