A method for determining a condition of the laser system includes
determining a change in a laser current from an initial value. A method
for measuring a laser current includes determining a difference between
the values of a power supply current, which is the value of the laser
current. A method for measuring a transmitted power includes generating a
first control signal that sets a magnitude of a bias current supplied to
a laser, generating a second control signal that sets a of a modulation
current supplied to the laser, and determining a difference between
values of a high and a low transmitted powers. A method for measuring a
received optical power includes determining a received OMA corresponding
to the power signal, which is the transmitted OMA minus a known loss
through a calibration fiber that couples the laser transmitter to the
laser receiver.