摘要 |
A method for protecting a passive optical transmission network comprising an optical line terminal (OLT) at least one remote node (RN), and a plurality of network termination nodes (ONU) A bidirectional optical signal transmission can be established between each ONU and the OLT via a first bidirectional optical transmission route by means of which an optical wavelength-multiplexed signal is transmitted in the downstream direction from the OLT to the one or more RNs and in the upstream direction from the one or more RNs to the OLT. A second bidirectional optical transmission route is provided between the OLT and the RNs where the wavelength-multiplexed signal is fed in the upstream direction both to the first and second optical transmission routes. On the detection of a fault state on the first or second optical transmission route, the OLT is switched to the other corresponding optical transmission route. |