TRANSMISSION DEVICE AND TRANSMISSION METHOD

PROBLEM TO BE SOLVED: To provide transmission device and method that can shorten pull-in time of a phase synchronization circuit.SOLUTION: A transmission device which receives from a network a signal transmission frame on which a client signal is mapped, separates the client signal from the received signal transmission frame, and transmits the separated client signal to a client transmission path by using a clock generated in a phase synchronization circuit on the basis of frequency adjustment information of the client signal contained in the signal transmission frame is provided with a memory for holding the frequency adjustment information contained in the signal transmission frame when the signal transmission frame can be received from the network, and a switching control circuit for making the phase synchronization circuit generate a clock by using the frequency adjustment information held in the memory when the signal transmission frame cannot be received from the network.