Method for identifying the optical network unit power off reason

An apparatus comprising:

• a non-transitory medium that stores computer executable instructions;
• and
• a processor that executes the computer executable instructions to cause the apparatus to perform the following:
• detect that an optical network terminal (ONT) meets one of a plurality of alarm conditions relative to power that are configured with respective alarm flags that indicate alarm reasons in ONT management and control interface (OMCI) alarm messages;
• and
• transmit, in response to the detecting, an OMCI alarm message with a corresponding alarm flag that indicates an alarm reason from the ONT,
• wherein the respective alarm flags comprise a first alarm flag that indicates the ONT is shutting down because a subscriber has turned off its power,
• wherein the first alarm flag corresponds to a first alarm condition of the plurality of alarm conditions relative to power,
• wherein the re alarm rise a second alarm a that ONT is shutting down due to loss of power to the ONT, and
• wherein the second alarm flag corresponds to a second alarm condition of the plurality of alarm conditions.

A passive optical network (PON) component comprising:

• a processor configured to:
• receive an interrupt message from a detector;
• and
• determine whether a reason for the interrupt is a power switch is switched to off, external power is abnormally off, or an internal circuit has a fault;
• and
• a controller configured to:
• store an occurrence of the interrupt;
• and
• store a time of the interrupt;
• and
• a transmitter coupled to the processor and configured to transmit a dying gasp message comprising an indicator of the reason for the interrupt.