Abstract: Methods and apparatus for managing an optical network using pilot tones are provided. One method includes selecting an optical path having a plurality of nodes from a database defining an expected optical network. A detected list of pilot tones associated with each node of the selected optical path is generated. An expected list of pilot tones associated with each node of the selected optical path is generated. The detected and expected lists are compared to identify any mismatched nodes.

Abstract: A way of testing a wavelength division multiplexed (WDM) system without requiring connection to data source/sink equipment. A test signal is introduced onto a light path of interest in the system, and the test signal is monitored downstream for signal integrity. Lack of signal integrity is used to identify a fault in the lightpath. Alternatively, optical loopbacks may be used to localize and identify a fault in the lightpath. The lightpath includes a source optical node connected to a sink optical node via intermediate optical nodes. An optical signal introduced at the source node with a destination at the sink node may be looped back at any one of the intermediate nodes or the sink node to localize and identify a fault in the lightpath.

Abstract: A way of testing a wavelength division multiplexed (WDM) system without requiring connection to data source/sink equipment. A test signal is introduced onto a light path of interest in the system, and the test signal is monitored downstream for signal integrity. Lack of signal integrity is used to identify a fault in the lightpath. Alternatively, optical loopbacks may be used to localize and identify a fault in the lightpath. The lightpath includes a source optical node connected to a sink optical node via intermediate optical nodes. An optical signal introduced at the source node with a destination at the sink node may be looped back at any one of the intermediate nodes or the sink node to localize and identify a fault in the lightpath.

Abstract: Methods and apparatus for managing static and dynamic optical network configurations to enable mapping an actual optical network or validating an expected optical network are provided. In one embodiment a validation method includes the step of selecting an optical path having a plurality of nodes from a database defining an expected optical network. A list of detected pilot tones from each node associated with the selected optical path is generated. An expected list of pilot tones associated with each node of the selected optical path is generated. Comparison of the expected and detected lists identifies any mismatched nodes. Another method includes the step of setting a first pilot tone source to have a first pilot tone value. All other network pilot tone sources are set to have another pilot tone value. An optical path associated with the first pilot tone source is then mapped by identifying each node of the network having the first pilot tone value.

Abstract: An optical communication system comprising plural optical communication paths, a passive optical coupler, and at least one optical node. The passive optical coupler has a plurality of inputs coupled through the passive optical coupler to an output of the passive optical coupler, and each input is coupled in a corresponding one of the optical communication paths. Each optical node comprises plural optical line terminals, each of which is interposed in a corresponding at least one of the optical communication paths. Each optical line terminal is operable to either (a) substantially prevent an optical signal propagating in that corresponding at least one optical communication path from reaching a corresponding input of the passive optical coupler through the at least one optical communication path, or (b) permit the optical signal to propagate in that corresponding at least one optical communication path towards the corresponding input of the passive optical coupler.

Abstract: A way of testing a wavelength division multiplexed (WDM) system without requiring connection to data source/sink equipment. A test signal is introduced onto a light path of interest in the system, and the test signal is monitored downstream for signal integrity. Lack of signal integrity is used to identify a fault in the lightpath. Alternatively, optical loopbacks may be used to localize and identify a fault in the lightpath. The lightpath includes a source optical node connected to a sink optical node via intermediate optical nodes. An optical signal introduced at the source node with a destination at the sink node may be looped back at any one of the intermediate nodes or the sink node to localize and identify a fault in the lightpath.

Abstract: A wavelength division multiplexed optical communication system includes a plurality of optical line terminals which may be part of separate in service networks, each having a line interface and an all-optical pass-through interface including a plurality of pass-through optical ports, and each also including a plurality of local optical ports which are connectable to client equipment and an optical multiplexer/demultiplexer for multiplexing/demultiplexing optical wavelengths. The optical multiplexer/demultiplexer may include one or more stages for inputting/outputting individual wavelengths or bands of a predetermined number of wavelengths, or a combination of bands and individual wavelengths.