Optical node for mesh-type WDM optical network

An N×N optical node capable of supporting a mesh-type optical network, where N is an integer greater than 1, the optical node comprising:

• N ROADMs, wherein each ROADM includes a drop module and an add module, the drop module separates specific wavelength channels from a multiple wavelength channel optical signal that is input from any directly connected node constituting the optical network and allows the wavelength channels not separated from the multiple wavelength channel optical signal to be passed, the add module combines added wavelength channels with the passed wavelength channels to allow the combined wavelength channel to be passed;
• an N×1 optical switch connected to the drop module and the add module of each ROADM, wherein the N×1 optical switch selects a specific wavelength channel separated by the drop module of one of the N ROADMs and inputs the specific wavelength channel into an optical transceiver and selects one of the N ROADMs and connects a wavelength channel that is output from the optical transceiver to the selected ROADM through the add module of the selected ROADM;
• and
• an electrical cross connect switch which drops a part of electrical signal bandwidth of the specific wavelength channels separated by the drop module of the selected ROADM, which is converted into the electrical signals in the optical transceiver, toward an external client and combines the rest of the electrical signal bandwidth with a electrical signal added by the external client to form an electrical signal bandwidth of a wavelength channel and output the electrical signal to the optical transceiver.