■
Alarm indication signal (AIS)
■
Equipment failure (does not affect service)
■
Frame error
■
Line code violation
■
Loss of signal (LOS)
■
Out of frame (OOF)
■
Yellow alarm bit (A-bit) disagreements
Alarms, errors, and
events
20
■
E3 PIC
M20 Internet Router PIC Guide: End-of-Life PICs