Availability

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Availability is a term used in Information Security, to show that a system is running and reachable by those that are supposed to be able to use the system.

Availability is sometimes expressed as a percentage of uptime, such as 99%. High availability is usually expressed as five nines - 99.999%. In a 24 hour, 7 day a week operation this would be just a little over 5 minutes per year!