Optical communication system and communication method

An optical communication system, comprising:

• at least two nodes, configured to at least one of receive or send an optical signal;
• a first wavelength selective switch (WSS), connected to a first node of the at least two nodes;
• a third WSS, connected to the first node;
• a second WSS, connected to a second node of the at least two nodes, wherein there is a first link between the first WSS and the second WSS, and there is a third link between the third WSS and the second WSS;
• and
• a fourth WSS, connected to the second node, wherein there is a second link between the third WSS and the fourth WSS, wherein
• the first WSS is configured to transmit a first optical signal with a first wavelength to the second WSS through the first link, and the second WSS is configured to transmit the first optical signal with the first wavelength to the second node;
• the third WSS is configured to transmit a second optical signal with a second wavelength to the fourth WSS through the second link, and the fourth WSS is configured to transmit the second optical signal with the second wavelength to the second node;
• the third WSS is configured to transmit a third optical signal with a third wavelength to the second WSS through the third link, and the second WSS is configured to transmit the third optical signal with the third wavelength to the second node;
• and
• the first node is configured to:
• send the first optical signal with the first wavelength to the first WSS, send the second optical signal with the second wavelength to the third WSS, and send the third optical signal with the third wavelength to the third WSS, wherein the first optical signal, the second optical signal, and the third optical signal carry a same service.