Distributed real-time systems

real-time systems form one category of specialized distributed systems named "distributed real-time systems". real-time programs(and systems) interact with the external world in a way that involves time. when a stimulus appears ,the system must respond to it in a certain way and before a certain dead line. Many real-time applications and systems are highly structured much more so than general purpose distributed systems. distributed real time systems are needed in large complex applications in which the CPU may have to deal with multiple event streams and when it will become more difficult for one machine to meat all the dead lines and real time constraints. Unlike other distributed systems ,the real time distributed systems can often be structured as a collection of computers connected by a network, some computers are Connected to external devices that produce or accept data or expect to be controlled in real time, and computers have sensors for receiving signals from devices or actuators for sending signals to them.