Fault-tolerant Computer System
A Fault-tolerant computer system is a type of computer system which is designed to continue working properly, even when some of its components or parts fail. This is accomplished by adding extra redundancies and backup components or processes, allowing the system to continue functioning with reduced performance or efficiency if any element of the system fails.
Fault-tolerant systems are typically designed for use in areas where failure of critical systems could have dangerous or catastrophic consequences. These include medical systems, communications systems, transportation systems, safety systems, military systems, etc. Fault-tolerant systems must be more precisely designed and built than ordinary computer systems, as they need to be able to detect faults and respond quickly and accurately.
Fault-tolerant computer systems are typically implemented using Redundant Array of Independent Disks (RAID) technology, as well as using other fault-tolerance techniques. RAID allows multiple hard drives to be connected together, allowing redundancy of data in the event of a disk drive failure. Other fault-tolerance techniques include redundant power supplies, redundant network connections, redundant data paths, and redundant processors.
Fault-tolerant computer systems are also often implemented using software-based fault-tolerance protocols, such as the TCP/IP protocol. These protocols allow the computer system to automatically detect and respond to faults, and to self-heal if possible.
In addition to providing fault-tolerance, fault-tolerant systems may also include automatic failover capabilities, allowing the system to switch to a backup system in the event of a component failure or power outage. This helps ensure that the system remains operational, even if part of it fails.
Fault-tolerant computer systems can be very expensive to purchase and maintain, but are often seen as essential in mission-critical applications where failure is not an option.
