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Topic: backup processor
topics >
computer science >
multiple processors
Topic:
replicated data
Topic:
safety critical systems
Summary
A real-time system needs to be continuously active despite software modifications, hardware maintenance, hardware failure, or software bugs. Distributed systems seem to be the most flexible, allowing graceful performance degradation. A successful fault-tolerant system is ARPANET with its dynamically routed messages giving full network operation despite component failure. A dedicated backup processor may be used with a watchdog timer, but automatic conversion is difficult. Some installations resort to manual conversion or to fully manual alternatives. (cbb 5/80)
Quote: use manual activation of a backup computer to avoid difficulties of an automatic changeover [»controleng] Quote: a process control system may lose major subsystems; must still be able to operate remotely or manually [»instrumentcontrol] Quote: for fault-tolerance, use swact (switch of activity) between active and passive forms of an application; passive form only keeps track of state of active form; resynchronizes on recovery
[»dereF3_2001]
Topic: multiple processors (10 items)
Topic: replicated data (51 items)
Topic: safety critical systems
(32 items)