 elements generate logs/alarms when an error condition occurs. Using a network management protocol these notifications can be collected from the network element. Executing diagnostics tests at regular intervals to check for issues: The element management can have its own set of rules to identify errors. For example the EMS can define severity for specific conditions of resource in the network element and do regular audits on the state of resources. When a state change happens, the new state of resource is compared with severity and a log is generated. Processing database information: The network element can have a database that stores static and dynamic information about the element. Querying this database will also provide information about fault condition. A detailed COV- erage of MIB (management information base) is later handled as a separate chapter in this book. ITU-T FCAPS There are other methods that an EMS uses to detect fault also. Some of them include checking and filtering the system logs on the network element, adding code that defines thresholds for attributes of the network element and generating an event when threshold is crossed, and SO on. Some EMS employ combinations of the above fault detection methods, like having the NE send event notifications as well as running routine checks if some data was lost or not sent by NE. Once detected, the fault needs to be isolated. Isolation includes identifying the element in the network or resource (can be a process or physical component) in the element that generated the fault. If the fault information is generic, then isolation would also involve filtering and doing data processing to isolate the exact cause of the fault. After the fault is detected and isolated, then it needs to be fixed. Correcting fault can be manual or automatic. In the manual method, once the fault is dis- played on a management application GUI, a technician can look at the fault information and perform corrective action for the fault. In the automatic method, the management applicat