Availability

The security goal that generates the requirement for protection against intentional or accidental attempts to:

1. perform unauthorized deletion of data, or

2. otherwise cause a denial of service or data.

NIST SP 800-27 Rev A

Ensuring timely and reliable access to and use of information.

Mission/ business resiliency objectives extend the concept of availability to refer toa point-in-time availability (i.e, the system, component, or device is usable when needed) and the continuity of availability (i.e., the system, component, or device remains usable for the duration of the time it is needed). NIST SP 800-160