Registration method for optical communication network, apparatus, network device, and system

A method, comprising:

• receiving, by a first network device, a serial number (SN) of the first network device, a registration identifier of the first network device, and a first ranging request packet that are sent by a second network device, wherein the registration identifier has a correspondence with the SN of the first network device, and the SN of the first network device is prestored in the second network device;
• sending, by the first network device, a first ranging packet to the second network device in response to the first ranging request packet, wherein the first ranging packet comprises the registration identifier;
• and
• receiving, by the first network device, a first response packet sent by the second network device, wherein the first response packet indicates a first equalization delay to be used by the first network device in an optical communication network.

A second network device, comprising:

• at least one processor and a transceiver, wherein the at least one processor and the transceiver are configured to collaboratively perform operations comprising:
• allocating a registration identifier to a first network device, wherein the registration identifier has a correspondence with a serial number (SN) of the first network device, and the SN of the first network device is prestored in the second network device;
• sending the SN of the first network device and the registration identifier to the first network device, and sending a first ranging request packet to the first network device;
• and
• receiving a first ranging packet from the first network device, and sending a first response packet to the first network device, wherein the first ranging packet carries the registration identifier, and the first response packet indicates a first equalization delay to be used by the first network device in an optical communication network.