摘要:
A hitless path switching method without a bit loss. A bit error in the same digital line signals is continuously monitored independently of a predetermined data blocks of a working path (51) and a protection path (61). If a bit error occurs in the working path and no bit error occurs in the protection path, a switching trigger is produced and the switching from the working path to the protection path is performed on the data block basis. Only correct data are transferred to downstream apparatuses. A reliable hitless switching is achieved not only in response to a failure in its own path, but also in response to a bit error. Using data blocks of one frame length with an indicator for bit error check placed at its top makes an effective switching possible.
摘要:
The invention has the object of offering a channel-selection-type demultiplexing circuit which is capable of interchanging the time slots of demultiplexed signals when demultiplexing ultra-high-speed multi-channel multiplexed signal stream without expanding the scale of the circuits, and does not require the scale of the circuits to be expanded even if the speed of the transmission path increases. The invention is a channel-selection-type demultiplexing circuit capable of demultiplexing signals to a desired output port during bit demultiplexing, instead of simply demultiplexing the bits as in conventional devices, which performs bit demultiplexing based on a frequency division clock after selecting the bit signals to be demultiplexed to the desired output port from the N -channel multiplexed signal stream based on channel selection information.
摘要:
In a trunk transmission network for transmitting information signals between nodes (A-C) via paths, flexible path operation is achieved by setting up paths between source nodes and destination nodes after pre-classifying paths into a higher service class (Class A) in which any loss of information occurring in that path is made good, and a lower service class (Class B) which permits loss of information to occur in the path, and by arranging for each node, when it acts as a source node, to recognise the service class of the information signal it is sending to a destination node, and to select a path corresponding to that service class.
摘要:
The invention has the object of offering a channel-selection-type demultiplexing circuit which is capable of interchanging the time slots of demultiplexed signals when demultiplexing ultra-high-speed multi-channel multiplexed signal stream without expanding the scale of the circuits, and does not require the scale of the circuits to be expanded even if the speed of the transmission path increases. The invention is a channel-selection-type demultiplexing circuit capable of demultiplexing signals to a desired output port during bit demultiplexing, instead of simply demultiplexing the bits as in conventional devices, which performs bit demultiplexing based on a frequency division clock after selecting the bit signals to be demultiplexed to the desired output port from the N -channel multiplexed signal stream based on channel selection information.
摘要:
In a trunk transmission network for transmitting information signals between nodes (A-C) via paths, flexible path operation is achieved by setting up paths between source nodes and destination nodes after pre-classifying paths into a higher service class (Class A) in which any loss of information occurring in that path is made good, and a lower service class (Class B) which permits loss of information to occur in the path, and by arranging for each node, when it acts as a source node, to recognise the service class of the information signal it is sending to a destination node, and to select a path corresponding to that service class.
摘要:
A hitless path switching method without a bit loss. A bit error in the same digital line signals is continuously monitored independently of a predetermined data blocks of a working path (51) and a protection path (61). If a bit error occurs in the working path and no bit error occurs in the protection path, a switching trigger is produced and the switching from the working path to the protection path is performed on the data block basis. Only correct data are transferred to downstream apparatuses. A reliable hitless switching is achieved not only in response to a failure in its own path, but also in response to a bit error. Using data blocks of one frame length with an indicator for bit error check placed at its top makes an effective switching possible.