Path protection in WDM network
First Claim
1. A node for use in a WDM optical network, the node comprising:
- a tributary receiver unit for receiving a data signal distributed via the WDM optical network and destined for said node, a path protection switching unit for switching receipt of said data signal at the tributary receiver unit from a working path to a protection path of the WDM optical network, and a control unit for the path protection unit, wherein the control unit comprises a multi rate clock data recovery (CDR) device arranged, in use, to detect a loss of lock (LOL) in the data signal received at the tributary receiver unit based on a comparison of an actual data rate received and a pre-programmed reference rate for said data signal.
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Accused Products
Abstract
A node for use in a WDM optical network, the node comprising a tributary receiver unit for receiving a data signal distributed via the WDM optical network and destined for said node, a path protection switching unit for switching receipt of said data signal at the tributary receiver unit from a working path to a protection path of the WDM optical network, and a control unit for the path protection unit, wherein the control unit comprises a multi rate clock data recovery (CDR) device arranged, in use, to detect a loss of lock (LOL) in the data signal received at the tributary receiver unit based on a comparison of an actual data rate received and a pre-programmed reference rate for said data signal.
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Citations
37 Claims
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1. A node for use in a WDM optical network, the node comprising:
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a tributary receiver unit for receiving a data signal distributed via the WDM optical network and destined for said node, a path protection switching unit for switching receipt of said data signal at the tributary receiver unit from a working path to a protection path of the WDM optical network, and a control unit for the path protection unit, wherein the control unit comprises a multi rate clock data recovery (CDR) device arranged, in use, to detect a loss of lock (LOL) in the data signal received at the tributary receiver unit based on a comparison of an actual data rate received and a pre-programmed reference rate for said data signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 21, 36)
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13. A node for use in a WDM optical network, the node comprising:
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one or more first network interface units arranged, in use, to demultiplex an incoming WDM optical signal and to convert the incoming WDM optical signal into a plurality of electrical channel signals, a plurality of 3R regeneration units for regenerating the electrical channel signals, one or more second network interface units arranged, in use, to convert and multiplex at least one of the electrical channel signals into an outgoing WDM optical signal, and wherein each 3R regeneration unit is arranged, in use, to detect a LOL in its associated electrical channel signal and to force its output to a substantially static state in response to detecting the LOL. - View Dependent Claims (14, 15, 16, 17)
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18. A method of conducting path protection in a WDM optical network, the method comprising the steps of:
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receiving a data signal at a tributary receiver unit of a network node, detecting a loss of lock (LOL) in the data signal received at the tributary receiver unit based on a comparison of an actual data rate received and a reference rate for said data signal, and switching receipt of said data signal at the tributary receiver unit from a working path to a protection path of the WDM optical network. - View Dependent Claims (19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 30, 37)
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31. A method of conducting fault notification in a WDM optical network from one network node to another, the method comprising the steps of, at said one network node,:
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demultiplexing an incoming WDM optical signal and converting the incoming WDM optical signal into a plurality of electrical channel signals, regenerating the electrical channel signals utilising 3R regeneration, and converting and multiplexing at least one of the electrical channel signals into an outgoing WDM optical signal, and wherein the step of 3R regenerating the electrical channel signals comprises detecting LOLs in the individual electrical channel signals and forcing the output of the 3R regeneration for individual electrical channels to a substantially static state in response to detecting the LOL. - View Dependent Claims (32, 33, 34, 35)
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Specification