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31 May 2001

Terminology

API
application programming interface

CPU
central processing unit

determinism, deterministic control
Determinism is the capacity for a computer network- driven control system to provide a piece of data every time, on time, without fail. Continuous process measurements such as temperature and pressure, where updates can be at 0.1-, 0.5-, or 1-second intervals are nondeterministic. Critical discrete applications require deterministic control and need scan times as fast as 1 millisecond to preclude lost machine cycles, damaged equipment, or injury.

fault tolerance
Fault tolerance is the ability to continue nonstop when a hardware failure occurs. A fault-tolerant system has multiple critical components such as CPUs, memory, disks, and power supplies in the same computer. If one component fails, another seamlessly takes over.

idempotent
Idempotent is a mathematical quantity that, when applied to itself under a given binary operation, equals itself.

middleware
Middleware is software that connects two otherwise separate applications. For example, a middleware product may link a database system to a Web server. This allows users to request data from the database using forms displayed on a Web browser. It's also known as plumbing because it connects two sides of an application and passes data between them.

OS
operating system

TCP
transmission control protocol, with Internet protocol, the main protocol of the Internet

 

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