| 摘要 |
The method for protected transmission between two nodes (1,2) of an optical communication network, where the nodes are linked by a bidirectional main line and a bidirectional relief line, comprises the steps of transmitting the protected data on the main line, transmitting the supplementary data on the relief line, and following the detection of a loss of the main-line signal in reception at instants (51,53) by the nodes (1,2), respectively, the interruption of the data emission at instants (52,54) on the main line by the respective node, and the emission start of the protected data on the relief line at instants (55,56) by that node. That is both nodes (1,2) can switch the emission of the protected data to the relief line. The detection of a loss of the signal is implemented by detecting a loss of the clock signal. The interruption of the emission on the main line comprises the extinction of laser at the node which emits on the main line. The step of interrupting the data emission on the main line and the emission start on the relief line is followed by the steps of sending a test signal at instants (57,58) on the main line by the respective node, and sending a reception acknowledgment signal at instant (60) on the main line when the node receives the test signal. When the reception acknowledgement signal is received, the node interrupts the emission of the protected data on the relief line and emits the protected data on the main line. The method also comprises the step of sending a confirmation signal on the main line by a node on receiving the reception acknowledgment signal. The test signal, the reception acknowledgment signal, and the confirmation signal are in the form of pulses distinguished by the length. |
