Optical Communications Method and Apparatus

An optical communications method, wherein the method is executed on a communications node that comprises an input optical modulator array and an output optical modulator array, wherein the input optical modulator array comprises N input optical modulators and the N input optical modulators are configured to receive a signal light, and the output optical modulator array comprises M output optical modulators and the M output optical modulators are configured to send the signal light, wherein M is greater than a number of output optical modulators that can be covered by one input optical modulator and/or N is greater than a number of input optical modulators capable of covering a same output optical modulator, the method comprising:

• determining, by a local communications node, a plurality of local input areas from the input optical modulator array, wherein the local input areas are used to receive a foreign signal light and the foreign signal light is a signal light that comes from a transmitter-side foreign communications node and needs to be sent to a receiver-side foreign communications node;
• and
• determining, by the local communications node, a plurality of local output areas from the output optical modulator array, wherein the local output areas are used to send the foreign signal light, wherein the local input areas correspond to the local output areas in a one-to-one mapping manner, and wherein each input optical modulator in a local input area is capable of transmitting a signal light to each output optical modulator in a corresponding local output area.