| 摘要 |
PROBLEM TO BE SOLVED: To obtain a transmission line terminating device which can constitute a redundant standby system on an optical path side and an SDH(synchronous digital hierarchy) side, requires a small hardware quantity, and has low-cost device constitution. SOLUTION: This transmission line terminating device is equipped with optical path signal terminating circuits 2-0 and 4-0 which terminate optical path signals, SDH selection signal terminating circuits 12-0 and 14-0 which terminate SDH signal, SDH path signal monitoring and processing circuits 8-0 and 10-0 which monitor or process SDH path signals included in the SDH signals or optical path signals, their redundant or standby systems 2-1, 4-1, 12-1, 14-1, 8-1, and 10-1, and an optical path and SDH switch circuit 6 which switches these redundant or standby system. In this case, the optical path and SDH switch circuit 6 is installed between the optical path signal terminating circuits 2-0, 2-1, 4-0, and 4-1 and SDH path signal monitoring and processing circuits 8-0, 8-1, 10-0, and 10-1 and used in common to switch the redundant system or standby system of the optical path signals and also to switch the redundant system or standby system of the SDH signals. |
