Optical amplifier transient control with gain error limits

A method of minimizing gain error in an optical communication system due to a transient event, the method comprising:

• detecting a transient event;
• upon detecting a transient event, comparing a change in an optical signal power of an optical amplifier to a threshold value;
• and
• adjusting a gain of the optical amplifier if the change in signal power is less than the threshold value, wherein the gain of the optical amplifier is adjusted in accordance with a difference between the change in signal power and the threshold values,
• wherein the optical signal includes a plurality of wavelength-division multiplexed (WDM) channels and the threshold value is a function of a change in signal power due to an intended change in the number of WDM channels, so that the intended change in the number of WDM channels is not detected as a transient event.