The return of alarms

SDH allows the sky to achieve the alarm on the various equipment. These alarms correspond to different problems could exist on the equipment or connections.
Major alarms are:
• AU-AIS (Administrative Unit Alarm Indication Signal)
• AU-LOP (Administrative Unit Loss of Pointer)
• HP-UNEQ (HO Path Unequipped)
• HP-RDI (HO Path Remote Defect Indication)
• LOF (Loss of Frame) Frame Loss
• LOS (Loss of Signal, drop in incoming optical power level
causes high bit error rate.) Loss of signal
• LOP (Loss of Pointer) Loss of Pointer
• LP-UNEQ (LO Path Unequipped)
Olivier ADAMUS SONET / WDM
Johann COPIN
Eric Panetta IR3 - 2003
22/30
• MS-AIS (Multiplex Section Alarm Indication Signal)
• MS-REI (Multiplex Section Remote Error Indication)
• MS-RDI (Multiplex Section Remote Defect Indication)
• OOF (Out of Frame)
• TU-AIS (Tributary Unit Alarm Indication Signal)
• TU-LOM (Loss of Multiframe)