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US 7,024,112 B2Granted
In-band wavelength conversion wavelength buffering and multi-protocol lambda switching
AssigneeOpVista Incorporated
InventorWinston Way
Life of this patent
Estimating the term…
Abstract
A method and device for wavelength conversion, wavelength buffering and label/header swapping. A wavelength buffer is used to provide for in-band wavelength conversion in, for example, a dense wavelength division multiplexing communications system. The same device may be used for label/header swapping without wavelength conversion.
Claims22
A method comprising:
- receiving a first packet of information on an input optical signal that occupies a plurality of input channels, each input channel being included in one among an input plurality of distinct wavelength ranges that are respectively in selected International Telecommunication Union (ITU) WDM windows;
- and
- transmitting the first packet of information on an output optical signal that occupies a plurality of output channels, each output channel being included in one among an output plurality of distinct wavelength ranges,
- wherein the plurality of input channels includes at least a plurality of WDM channels within one ITU WDM window which comprise:
- (A) a reserved wavelength buffer selected from one of the plurality of adjacent WDM channels within the one ITU WDM window;
- and
- (B) a channel on which the first packet is received,
- wherein the plurality of output channels includes an active wavelength buffer on which the first packet is transmitted, and
- wherein each among the input plurality of wavelength ranges is associated, in order of increasing wavelength, with one among the output plurality of wavelength ranges in order of increasing wavelength, the wavelength range including the reserved wavelength buffer being associated with the wavelength range including the active wavelength buffer,
- wherein the method further comprises:
- extracting label information, the first packet of information, and a carrier from the input optical signal;
- producing a first electronic signal representing information from the first packet of information;
- and
- producing a second electronic signal representing the label information,
- wherein transmitting the first packet of information further comprises modulating the carrier with the first and second electronic signals to produce the output optical signal.
12 more elements
A device, comprising:
- an optical input port to receive a wavelength-division multiplexed (WDM) signal having a plurality of different WDM channels within each single International Telecommunication Union (ITU) WDM window, wherein at least one of the WDM channels is empty and is reserved as a buffer channel;
- an optical splitter to split the received WDM signal into first, second and third optical signals;
- a label processing module to process label information in the first optical signal to produce a first electrical control signal having new label information for a channel shifting arrangement;
- an optical filter to filter the second optical signal to remove modulation bands thereon to produce an optical carrier signal;
- a data signal regenerator to receive the third optical signal to process data in each WDM channel in the third optical signal to generate a second electrical control signal having data in the received WDM signal;
- and
- an optical modulator to modulate the optical carrier signal in response to the first and the second electrical control signals to shift a selected WDM channel to the buffer channel according to the channel shifting arrangement to produce a new WDM signal.
4 more elements
A method, comprising:
- separating a received wavelength-division multiplexed (WDM) signal comprising a plurality of different WDM channels within a single International Telecommunication Union (ITU) WDM window into a first optical signal carrying a WDM channel that has label information of the WDM channels, and a second optical signal at an optical carrier frequency without WDM channels, and a third optical signal comprising WDM channels carrying data and at least one empty WDM channel which is reserved as a buffer channel;
- converting the third optical signal into an electronic data signal wherein a signal channel corresponding to a selected WDM channel is shifted to a signal channel that corresponds to the buffer channel;
- converting the first optical signal into an electronic label signal which has new label information to reflect updated channel information after channel shifting in the electronic data signal;
- and
- modulating the second optical signal to produce a new optical WDM signal having WDM channels therein which carry a new label channel with the updated channel information and data.
2 more elements
A method, comprising:
- receiving an optical wavelength-division multiplexed (WDM) signal having an optical carrier and WDM channels at WDM channel frequencies different from the optical carrier in an optical WDM network,
- separating the received WDM signal into a first optical signal carrying a WDM channel that has label information of the input WDM signal, and a second optical signal which is the optical carrier only, and a third optical signal comprising WDM channels carrying data;
- converting the first optical signal into an electronic label signal which has label information of the WDM channels in the received WDM signal;
- optically filtering the third optical signal, in response to a control signal generated from the electronic label signal, to produce a filtered third optical signal that carries a selected WDM channel;
- converting the filtered third optical signal into an electrical signal to extract data of the selected WDM channel and to make the selected WDM channel available for carrying data;
- and
- modulating the second optical signal to carry a new WDM channel and a new WDM label channel, wherein the new WDM label channel includes channel information of the new WDM channel.
4 more elements
A device, comprising:
- an optical input port to receive an optical wavelength-division multiplexed (WDM) signal having an optical carrier and WDM channels at WDM channel frequencies different from the optical carrier,
- an optical element to separate the received optical WDM signal into first, second and third optical signals;
- a label processing module to process label information of the received optical WDM signal in the first optical signal to produce a first control signal;
- a first optical filter to filter the second optical signal to remove any modulation bands thereon to produce a filtered second optical signal which includes the optical carrier only;
- a second optical filter to filter the third optical signal, in response to the fist control signal, to produce a filtered third optical signal that carries a selected WDM channel;
- a signal regenerator to extract data of the selected WDM channel to produce a dropped signal containing the extracted data;
- and
- an optical modulator to modulate the filtered second optical signal to carry a new WDM channel and a new WDM label channel, wherein the new WDM label channel includes channel label information of the new WDM channel.
5 more elements
Dependencies are inferred from the claim text.