Optical switch control method, an optical switch controller, and an optical transmission system

The optical switch controller, each of a plurality of input ports (102) respectively provided between the plurality of output ports (103), the transmission of light from a plurality of input ports (102) to a plurality of output ports (103) drive controller for controlling a plurality of light switches off (105) comprises a (106), the drive control unit (106), from the control to switch off the light switch (105) from oN, oFF the optical switch (105) performed with priority control for switching on from.