availability

availability

The accessibility of a system resource in a timely manner; for example, the measurement of a system's uptime. Availability is one of the six fundamental components of information security (see Parkerian Hexad). See also uptime and high availability.

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availability [ə‚vāl·ə′bil·ə·dē]

(computer science)

Of data, data channels, and input-output devices in computers, the condition of being ready for use and not immediately committed to other tasks.

(navigation)

The probability that a navigational system will function and provide required levels of accuracy, integrity, and continuity.

(physics)

The difference between the enthalpy per unit mass of substance and the product of entropy per unit mass multiplied by the lowest temperature available to the substance for heat discard; used in determining the ratio of actual work performed during a process by a working substance to that which theoretically should have been performed.

(systems engineering)

The probability that a system is operating satisfactorily at any point in time, excluding times when the system is under repair.

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(system)

availability - The degree to which a system suffers degradation or interruption in its service to the customer as a consequence of failures of one or more of its parts. One of the components of RAS.