Patent ID: 6169753
Filing Date: 2001-01-02
Classification: H04J

Abstract:
A transmission device employing a network synchronization system for relay-transmitting a transmission signal from a transmitting side to a receiving side in synchronization with a clock signal, said transmission device comprising: a clock extracting unit for extracting a plurality of clock signals from a plurality of received signals; a selecting unit for selecting any one of said plurality of clock signals supplied from said clock extracting unit for transmitting Paid transmission signal to said receiving side; a relay-transmitting unit for relay-transmitting said transmission signal to said receiving side by using said clock signal selected by said selecting unit; an identification information notifying unit for notifying said receiving side of identification information used for identifying a clock supply system for supplying said clock signal selected by said selecting unit; a relay-receiving unit for relay-receiving said transmission signal from said transmitting side; an identification information extracting and recognizing unit for extracting and recognizing identification information regarding a clock signal contained in said transmission signal relay-received by said relay-receiving unit; and an inhibition setting unit for inhibition setting said selecting unit to select, as a clock signal contained in said transmission signal to be relay-transmitted, a clock signal contained in a transmission signal previously relay-transmitted by said relay-transmitting unit based on a result of recognizing identification information by said identification information extracting and recognizing unit.