FDIR
FDIR is the abbreviation for Fault-Detection, Fault-Isolation and Recovery Techniques , sometimes also Fault-Detection, Fault-Isolation and Restoration / Reconfiguration and sometimes, depending on the sharpness of the definition, also as Fault Detection and Exclusion (FDE) or Error Detection and Correction (EDAC).
For example, one tries to equip software systems with self-healing algorithms. The program should be able to detect failures without external intervention ( fault detection , watchdog ). In the next step, the system tries to isolate and determine the fault ( fault isolation , e.g. switching off defective components) in order to then carry out appropriate corrections ( recovery , e.g. switching to replacement components and restarting the system).
Another example is the fault-tolerant coding of data, for example with a Hamming code and checksum. Individual incorrect bits in data words can be recognized and corrected. When the error density increases, the correction fails, then the localization of incorrect data words, and finally the general recognition of errors.
Autonomous systems such as satellites are already rudimentarily equipped with FDIR technologies. For example, if a sensor delivers unexpected data, the system recognizes it as the cause of the error, switches it off and activates redundant components.