Timeout (computing)

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In telecommunications and related engineering (including computer networking and programming), the term timeout or time-out has several meanings, including:

• A network parameter related to an enforced event designed to occur at the conclusion of a predetermined elapsed time.
• A specified period of time that will be allowed to elapse in a system before a specified event is to take place, unless another specified event occurs first; in either case, the period is terminated when either event takes place. Note: A timeout condition can be canceled by the receipt of an appropriate time-out cancellation signal.
• An event that occurs at the end of a predetermined period of time that began at the occurrence of another specified event. The timeout can be prevented by an appropriate signal.

Timeouts allow for more efficient usage of limited resources without requiring additional interaction from the agent interested in the goods that cause the consumption of these resources. The basic idea is that in situations where a system must wait for something to happen, rather than waiting indefinitely, the waiting will be aborted after the timeout period has elapsed. This is based on the assumption that further waiting is useless, and some other action is necessary.