Reliable computer systems (2nd ed.): design and evaluation
Reliable computer systems (2nd ed.): design and evaluation
| Hi-index | 0.00 |
A system is said to be nonredundant or is said to have a simplex structure if it is designed such that only the absolute minimum amount of hardware is used to implement its function. If, even after using the finest components available, the desired system reliability is not achieved, or if failure tolerance is desired as a system capability, then redundancy is incorporated into the design; i.e. more system elements are used than are absolutely necessary to realize all the system's functions. The additional system elements, referred to as the redundant elements, need not all necessarily be hardware elements, but may also be additional software (software redundancy), additional time (time redundancy-e.g. performing a computation more than once and comparing the results), and additional information (information redundancy-e.g. the application of error-detection and correction codes).