PURPOSE: To manage a connection of a path definitely even when a path is changed and a degree of multiplex is overlapped by sending a connection path information collection command of a path or a section with higher degree of multiplex to a transmission area based on the result of detection of a connection path information collection command of a path or a section in the minimum unit able to be identified by a cross connect device.

CONSTITUTION: When a section 1 is inputted to a deice 30 making cross connect on an N-th path, the N-th path is separated into a connection path information collection command transmission area 11 provided on the section 11, and (N-1)th paths 2,5. an (N+1)th path 2 is separated into a connection path information collection command transmission area 12 provided to the (N+1)th path and N-th paths 3,4. Similarly, an (N+1)th path 5 is separated into a connection path information collection command transmission area 15 provided to the (N+1)th path and N-th paths 6,7. A device 30 makes cross connection of N-th paths 3,4,6,7 separated into the unit of N-th paths. Then the N-th path is multiplexed in the unit of sections and the result is sent to a succeeding device.