WO2010036268A1 - Système de communications modulaire basé wss comportant des interfaces à insertion/extraction sans couleur - Google Patents

Système de communications modulaire basé wss comportant des interfaces à insertion/extraction sans couleur Download PDF

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Publication number
WO2010036268A1
WO2010036268A1 PCT/US2008/078034 US2008078034W WO2010036268A1 WO 2010036268 A1 WO2010036268 A1 WO 2010036268A1 US 2008078034 W US2008078034 W US 2008078034W WO 2010036268 A1 WO2010036268 A1 WO 2010036268A1
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WO
WIPO (PCT)
Prior art keywords
optical
board
chassis
add
drop
Prior art date
Application number
PCT/US2008/078034
Other languages
English (en)
Inventor
Jeffrey J. Maki
Christopher M. Look
Original Assignee
Dynamic Method Enterprises Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dynamic Method Enterprises Limited filed Critical Dynamic Method Enterprises Limited
Priority to CN200880000284A priority Critical patent/CN101809912A/zh
Priority to PCT/US2008/078034 priority patent/WO2010036268A1/fr
Publication of WO2010036268A1 publication Critical patent/WO2010036268A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0204—Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or dropping
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0205—Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0206—Express channels arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0209—Multi-stage arrangements, e.g. by cascading multiplexers or demultiplexers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/021—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM]
    • H04J14/0212—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM] using optical switches or wavelength selective switches [WSS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/021—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM]
    • H04J14/02122—Colourless, directionless or contentionless [CDC] arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0213—Groups of channels or wave bands arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0215—Architecture aspects
    • H04J14/0217—Multi-degree architectures, e.g. having a connection degree greater than two
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0215—Architecture aspects
    • H04J14/0219—Modular or upgradable architectures
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H04Q2011/0007—Construction
    • H04Q2011/0015—Construction using splitting combining
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H04Q2011/0007—Construction
    • H04Q2011/0016—Construction using wavelength multiplexing or demultiplexing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H04Q2011/0052—Interconnection of switches

Definitions

  • the present invention relates generally to optical networking systems. More particularly, this invention relates to modular WSS-based communications systems with colorless add/drop interfaces that are not network-port assigned.
  • the application covers the creation of a colorless and transparent mesh optical network, where we define colorless to mean no fiber or component is pre- as signed a specific operating channel wavelength and where we define transparent to mean no node of the network becomes blocking for any subset of the operating channel wavelengths passing through to other nodes or being added/dropped from/to a specific colorless (tunable) transponder.
  • Three forms of blocking are explicitly considered: (1) Contention where a channel wavelength is already in use between two or more nodes and thus preventing a distant node from using that channel wavelength to send a signal through those two or more nodes when no optical-to-electrical-to- optical (OEO) conversion is employed at the intermediate nodes.
  • OFE optical-to-electrical-to- optical
  • mesh optical networks can be based on NxN space-switch matrices. Transparency is lost when the equipment is not fully populated at each node, so that certain channel wavelengths are not supported, which is called channel blocking. NxN switches must be installed for each channel wavelength to avoid blocking regardless of the degree of the network at that node.
  • mesh optical networks can be based on interconnecting "East- West” Reconfigurable Optical Add/Drop Multiplexers (ROADMs) when based on Wavelength Selective Switch (WSS) modules. It is the means of doing adds/drops with "East- West” ROADMs that causes transparency to be lost.
  • ROADMs Reconfigurable Optical Add/Drop Multiplexers
  • a modular WSS-based Communications system with colorless and transparent add/drop interfaces is described herein.
  • equipment architecture is provided that enables a mesh optical network.
  • the embodiments of the invention are primarily on how to add and drop signals at a node of the network in a network port and wavelength independent fashion.
  • the embodiments include (a) a modular arrangement of the hardware enabling components such as a WSS to plug into a chassis containing optical and electronics backplanes, (b) provision for uninterrupted service while adding the modules, (c) the ability to monitor the quality of the optical signal(s) at ingress and egress to the node, (d) the ability to perform diagnostic functions such as optical loop-back, and (e) provisions for service restoration in the event of a fiber or equipment failure.
  • WSS wavelength selective switch
  • an optical network apparatus such as an optical network node, including: a main chassis having a plurality of slots coupled to with a control backplane, an optical backplane, and an electrical backplane; one or more cross-connect boards inserted into first slots of the main chassis and coupled to the control backplane and the optical backplane, the one or more cross-connect boards, each having a network ingress port and a network egress port, forming an optical cross-connect including one or more network ingress ports and egress ports; an add-drop board inserted into a second slot of the main chassis, wherein one or more channel- wavelength optical signals are capable of being added via the add-drop board onto one of the egress ports of the cross-connect board and one or more of the same channel- wavelength optical signals are capable of being dropped via the add-drop board from one of the ingress ports of the cross-connect board; a transmit-receive board inserted into a third slot of the main chassis, wherein one or more transmitter
  • the optical network node may further include an alien- wavelength board inserted into a fifth slot of the main chassis, wherein one or more channel- wavelength optical signals are capable of being added via the alien- wavelength board onto one of the egress ports of the one or more cross-connect boards and one or more of the same channel- wavelength optical signals are capable of being dropped via the alien-wavelength board from one of the ingress ports of the one or more cross-connect boards.
  • an alien- wavelength board inserted into a fifth slot of the main chassis, wherein one or more channel- wavelength optical signals are capable of being added via the alien- wavelength board onto one of the egress ports of the one or more cross-connect boards and one or more of the same channel- wavelength optical signals are capable of being dropped via the alien-wavelength board from one of the ingress ports of the one or more cross-connect boards.
  • the main chassis may further include an optical chassis having a plurality of slots and an electrical chassis having a plurality of slots, the optical chassis being coupled to the control backplane and optical backplane and the electrical chassis being coupled to the control backplane and the electrical backplane, wherein the cross-connect board, the add-drop board, and the alien- wavelength board are inserted into slots of the optical chassis, and wherein the transmitter-receiver board and the optical-2R board are inserted into slots of the electrical chassis.
  • the interfaces of the optical chassis and the electrical chassis may be colorless, wavelength-channel transparent, and network-port transparent add/drop interfaces for a linear, ring, and mesh all-optical network.
  • the same wavelength-channel may be reused by multiple different transmitters or receivers located in the same main chassis or electrical chassis when connected to multiple different add-drop boards respectively.
  • the transmitters or receivers located on the main chassis or the electrical-chassis may be connected to the same Add-Drop board.
  • the optical network node according to any of the preceding claims, wherein at least one of optical broadcasting and multicasting is provided for adding a channel-wavelength signal from one of the transmit-receiver board and the optical-2R board.
  • the optical backplane may comprise one or more layers of optical backplane fabric.
  • An additional chassis may be connected to the main chassis and additional boards may be inserted into slots of each chassis.
  • Multiple identical boards may be inserted into multiple slots of one of the main chassis, optical chassis, and electrical chassis, and wherein at least one board may be used to back up another board for redundancy purposes.
  • the cross-connect board may further include a dispersion compensation unit compatible with the colorless and port-transparent add/drop interfaces.
  • the optical network node may further include multi-channel optical channel monitors (OCMs) implemented in the cross-connect board, the add-drop board, and the alien- wavelength board.
  • OCMs optical channel monitors
  • the optical network node may further include: a first cross-connect board and a second cross-connect board as an auxiliary board to the first cross-connect board that has an (N-l)xl switch on its ingress and a Ix(N-I) switch on its egress for selecting a first cross-connect board if the first cross-connect board fails; a splitter coupled to transmit a copy of ingress signals to the second cross- connect board if the first cross-connect board fails; and a combiner coupled to transmit a copy of egress signals from the second cross-connect board back to the egress of the first cross-connect board.
  • the optical network node may further include: a first cross-connect board and a second cross-connect board as an auxiliary board to the first cross-connect board that has an (N-l)xl switch on its ingress and a Ix(N-I) switch on its egress for selecting a first cross-connect board if the first cross-connect board fails; a 1x2 switch to transmit alternatively the ingress signals to the second cross- connect board if the first cross-connect board fails; and a 2x1 switch to transmit the egress signals from the second cross-connect board back to the egress of the first cross-connect board.
  • the cross-connect board may be compatible with slot interfaces of at least one of the main chassis and optical chassis.
  • the add-drop board may be compatible with slot interfaces of at least one of the main chassis and optical chassis.
  • the alien- wavelength board may be compatible with slot interfaces of the at least one of the main chassis and optical chassis.
  • the transmitter-receiver board may be compatible with slot interfaces of the at least one of the main chassis and electrical chassis.
  • the optical-2R board may be compatible with slot interfaces of the at least one of the main chassis and electrical chassis.
  • the main chassis, optical chassis or electrical chassis may be implemented having fewer slots for supporting a relatively small network node.
  • the optical network node may further include a distribution-aggregation board compatible with the main chassis for forming a dedicated add-drop chassis, which is colorless and network-port transparent, for connection with the cross-connect board directly, with a dedicated single-channel and multi-channel transmitter-receiver board and a dedicated single-channel and multi-channel optical-2R board.
  • the optical network node may additionally include one or more single or multi-channel transmitter-receiver boards inserted into the add-drop chassis.
  • the optical network node may further include one or more single or multi-channel optical-2R boards inserted into the add-drop chassis.
  • the optical network node may further include an expanded chassis originated from the main chassis to function as an east- west ROADM, when using two or more cross-connect boards, one or more east-west transmitter-receiver boards, or one or more optical-2R boards.
  • FIG. 1 shows a certain embodiment of a conventional WSS module with arrows to show the direction of the optical signal transmission when used as a IxN
  • Fig. 2A shows the symbols used to depict WSS modules in a IxN or an
  • Fig. 2B shows the symbol used to depict a standard M-port optical splitter/combiner in a IxM splitter or MxI combiner usage, where it is to be understood that the splitter/combiner has little or no wavelength dependence.
  • Figs. 3-5 show WSS modules used to form Optical Cross-Connects (OXCs) according to certain embodiments of the invention.
  • Fig. 6 shows a conventional WSS system with OXC and add/drop ports.
  • Figs. 7-19 show WSS systems with OXC and add/drop ports according to certain embodiments of the invention.
  • Figs. 20-21 show network configurations with working and protection paths using WSS systems according to certain embodiments of the invention.
  • Fig. 22 shows all of the fabric-layers of Optical backplane together.
  • Figs. 23-25 show WSS systems with OXC and add/drop ports according to certain embodiments of the invention.
  • Figs. 26-27 show tunable transponders (transmitters and receivers) according to certain embodiments of the invention (i.e., Transmitter- Receiver boards).
  • Figs. 28-29 show WSS systems with tunable transponders (transmitters and receivers) according to certain embodiments of the invention.
  • Figs. 30-31 show wavelength-converting optical-2R devices according to certain embodiments of the invention (i.e., Optical-2R boards).
  • Figs. 32-33 show WSS systems with wavelength-converting optical-2R devices according to certain embodiments of the invention.
  • Fig. 34 shows boards providing add/drop ports for WSS systems suitable for alien wavelengths according to certain embodiments of the invention (i.e., Alien- Wavelength boards).
  • Fig. 35 shows a summary of Cross-Connect boards for WSS systems according to certain embodiments of the invention.
  • Fig. 36 shows a summary of Add-Drop boards providing add/drop ports for WSS systems according to certain embodiments of the invention.
  • Fig. 37 shows a summary of Transmitter- Receiver boards according to certain embodiments of the invention.
  • Fig. 38 shows a summary of optical-2R boards according to certain embodiments of the invention.
  • Fig. 39 shows a summary of Alien- Wavelength boards and those Add- Drop boards that can function as Alien- Wavelength boards for WSS systems according to certain embodiments of the invention.
  • Figs. 40-41 show Dispersion-Managed Cross-Connect boards with dispersion-compensator devices for WSS systems according to certain embodiments of the invention.
  • Fig. 42 shows Cross-Connect boards with optical channel monitors (OCMs) for WSS systems according to certain embodiments of the invention.
  • Fig. 43 shows Add-Drop boards with optical channel monitors (OCMs) for WSS systems according to certain embodiments of the invention.
  • Fig. 44 shows Alien-Wavelength boards with optical channel monitors (OCMs) for WSS systems according to certain embodiments of the invention.
  • Figs. 45-46 show protection schemes for failure of Cross-Connect boards in WSS systems according to certain embodiments of the invention.
  • Fig. 47 shows a Super (i.e., main) chassis consisting of Optical, Electrical, and Control backplanes with board slots for WSS systems according to certain embodiments of the invention.
  • Fig. 48 shows an Optical chassis consisting of Optical and Control backplanes with board slots for WSS systems according to certain embodiments of the invention.
  • Fig. 49 shows an Electrical chassis consisting of Electrical and Control backplanes with boards slots for WSS systems according to certain embodiments of the invention.
  • Fig. 50 shows configurations of the Super chassis either alone or with one or more Electrical chassis for WSS systems according to certain embodiments of the invention.
  • Fig. 51 shows an Optical chassis with one or more Electrical chassis for WSS systems according to certain embodiments of the invention.
  • Fig. 52 shows a Super-chassis WSS system according to certain embodiments of the invention.
  • Figs. 53-55 show a Super-chassis WSS system with expansion using an Electrical chassis according to certain embodiments of the invention.
  • Figs. 56-57 show a WSS system using an Optical and Electrical chassis according to certain embodiments of the invention.
  • Figs. 58-61 shows a Junior-chassis WSS system based on a scaled-down
  • Figs. 62-66 show Super chassis used to form an Add-Drop chassis for
  • Figs. 67-68 show WSS systems with an OXC-configured Optical chassis and a configured Add-Drop chassis according to certain embodiments of the invention.
  • Fig. 69 shows a summary of WSS-based Distribution- Aggregation boards for use with an Add-Drop chassis according to certain embodiments of the invention.
  • Fig. 70 shows Single-Channel and Multi-Channel Transmitter-Receiver boards that are compatible with the Add-Drop chassis according to certain embodiments of the invention.
  • Fig. 71 shows Single-Channel and Multi-Channel Optical-2R boards that are compatible with the Add-Drop chassis according to certain embodiments of the invention.
  • Figs. 72-77 show an Expanded East- West ROADM according to certain embodiments of the invention.
  • Fig. 78 shows a summary of East- West Transmitter- Receiver boards according to certain embodiments of the invention.
  • Fig. 79 shows a summary of East- West Optical-2R boards according to certain embodiments of the invention.
  • Fig. 80 shows an optical-backplane layer of the Super chassis required for an Add-Drop chassis.
  • Fig. 81 shows optical-backplane layers of the Super chassis required for an
  • an equipment architecture that enables a mesh optical network.
  • the embodiments of the invention are primarily on how to add and drop signals at a node of the network.
  • the embodiments of the invention are based on the use of a wavelength selective switch (WSS), which is an emerging component/module technology.
  • WSS wavelength selective switch
  • any node of the possible mesh network is scalable from degree 1 up to the degree N of the WSS.
  • the number of bidirectional network ports supported by the node can be no larger than the difference between the number of WSS-module ports, N, and the number of Add- Drop modules, where the number of Add-Drop modules is always less than N.
  • the wavelength Add-Drop modules described herein require fewer (as compared to alternative architectures) or no IxN, NxI, or NxN space switches, which thus reduces cost and complexity.
  • the slots of the chassis can be made to be generic so modules may be placed in arbitrary slots. The modules can be hot swappable, and thus enable a node to be upgradeable and down-gradable whilst in service.
  • Optical 2R with optional wavelength conversion are easily provided by a separate optional module similar to a module consisting of tunable transponders.
  • the optical modules of the system are compatible with each other allowing for a common chassis to interconnect them all, with any module using any slot.
  • This optical network design makes possible a metropolitan area mesh network that may be deployed to fit minimum initial needs for degree and active channel plan, yet is scalable to higher degree and expanded active channel plan, while being cost minimized for each level of deployment.
  • embodiments of the invention include an equipment architecture that enables a modular and scalable, colorless and transparent, optical- communications system.
  • no optical fiber or optical component is wavelength assigned or network-port assigned before being used as compared to prior art that generally has the wavelength and/or the network port pre-determined at the time of physical connection.
  • the system provides for arbitrary wavelength reconfiguration and arbitrary selection of network-port for connection with a given transponder. The particular wavelength selection is limited by the tunability of the components.
  • the components are intended to be tunable over the C-band, L-band, S- band, or superset such as C- and L-bands.
  • C-band operation could include at least 40 channels at 100 GHz spacing or 80 channels at 50 GHz spacing.
  • the typical exact channel wavelengths would be expected to follow the International Telecommunications Union standard known as the ITU grid.
  • An embodiment of the invention makes use of wavelength selective switch (WSS) component/module technologies.
  • WSS wavelength selective switch
  • Shown in Fig. 1 is an example of a 1x4 WSS prior art that portrays some functionality. It has 4 ports of which up to 8 possible channel wavelengths may be routed.
  • the WSS is found in two varieties of usage as shown in Fig. 2A, a IxN WSS and an NxI WSS.
  • the IxN WSS partially or fully demultiplexes incoming multiple channel-wavelength signals from a single network fiber and routes them to N output ports.
  • each output port of the IxN WSS may have one or more channel- wavelength signals.
  • the signals are mutually exclusive between the output ports when broadcasting/multicasting, if available in the WSS, is not employed.
  • each channel may be attenuated and even blocked, so that not all input signals necessarily are output by the IxN WSS.
  • the NxI WSS multiplexes the single or multiple channel- wavelength signals from each of the N input ports to a single output port. Similar to the IxN WSS, each channel may be attenuated and even blocked, so not all input signals necessarily are output by the NxI WSS.
  • this blocking feature is highly important when signals are not mutually exclusive between the input ports. By blocking all but one signal of the same channel wavelength, optical and hence electrical interference at the receiver is prevented, which is typically required.
  • the NxI WSS is essentially a IxN WSS operating in reverse direction of optical propagation and is optimized for wavelength multiplexing input signals from the N ports of the WSS onto a single outgoing network fiber.
  • Another embodiment of the invention makes use of both wavelength selective switch (WSS) component/module technologies and optical splitters/combiners.
  • WSS wavelength selective switch
  • a splitter/combiner is found in two varieties of usage as shown in Fig. 2B, a IxM splitter and an MxI combiner.
  • IxN WSS component/module for a IxM splitter, the same multiplexed wavelength signals that appear on the input to a splitter always also appear on all of the output ports of the splitter, which is optical broadcasting or multicasting.
  • NxI WSS component/module for an MxI combiner, all wavelength signals at the M inputs always appear multiplexed at the output of the combiner. There is no ability to block selectively wavelength signals passing through a splitter/combiner.
  • Fig. 3 is a possible degree-8 node of a communications system based upon IxN and NxI wavelength selective switches for N > 8 according to one embodiment. This is also referred to case #1.
  • major components are spread over a set of Cross-Connect boards placed into slots of a chassis, where each board in a slot provides bidirectional communication with a remote node.
  • the chassis includes backplanes to interconnect the boards optically and electrically.
  • the optical fibers interconnecting the IxN and NxI WSS form the Optical backplane.
  • One of the advantages of using two WSSs for each Cross-Connect board placed in a slot is that the crosstalk is greatly reduced owing to the double isolation according to certain embodiments of the invention.
  • Fig. 4 gives an alternative approach for making a degree-8 node for N > 8 according to certain embodiments. This is also referred to as case #2, where each Cross-Connect board placed in a slot has one IxN WSS and one NxI combiner, where again each populated slot provides bidirectional communication with another node.
  • the extinction of the single IxN WSS may be greater than or equal to the combined isolation of the two WSSs used in the first approach shown in Fig. 3 to achieve the same level of performance.
  • a weakness of this embodiment is that if one or more IxN WSS modules were to fail, then stray channel- wavelength signals would be sent to modules in other slots and/or lack proper power balancing owing to the potential failure of the VOA capability of the WSS. Note that such an occurrence would be deleterious considering that the NxI combiners lack the ability to block selectively these errant channel- wavelength signals or provide power balancing.
  • FIG. 5 Another embodiment shown in Fig. 5 is similar to that shown in Fig. 4, but with the IxN WSSs replaced with IxN splitters and the NxI combiners returned to being NxI WSSs. This is also referred to as case #3, where each NxI WSS would be relied upon to block the wavelength channels of each of the N input ports not meant to be part of the multiplexed output.
  • the isolation of the single IxN WSS must be greater than or equal to the combined isolation of the two WSSs used in the first approach shown in Fig. 3 to achieve the same level of performance.
  • Fig. 3 Fig. 4, and Fig. 5, the triangles with the letters P and B represent respectively a pre-amp and a booster optical amplifier.
  • Example optical amplifiers are the Erbium-doped fiber amplifier (EDFA) and the semiconductor optical amplifier (SOA), according to certain embodiments of the invention.
  • the pre-amp amplifies multiplexed signals entering the optical cross-connect and the booster amplifies multiplexed signals leaving the optical cross connect.
  • the thick solid lines represent optical fibers carrying multiplexed channel-wavelength signals that travel between nodes such as the possible 40 channels.
  • the medium thick lines represent optical fibers carrying multiplexed or partially demultiplexed channel- wavelength signals between boards (modules).
  • the narrow rectangular boxes that are drawn using a dashed line represent slots of a potential chassis. Modular Add-Drop System Examples
  • Fig. 6 is a conventional approach for adding and dropping signals.
  • the approach is restrictive in two ways. 1)
  • the optical fibers for adding or dropping signals are wavelength assigned owing to the use of wavelength-assigned multiplexers and demultiplexers for the adding and dropping of signals, respectively.
  • the adding and dropping is done separately for each remote node that signals are being respectively transmitted or received, which means separate banks of transmitters and receivers (e.g., transponders) would be required for communications with each remote node. Separate banks of transmitters and receivers would be expensive and bulky.
  • a modular add-drop approach is utilized that does not possess the two kinds of problems (bottlenecks) of the conventional approaches.
  • An Add-Drop board is utilized that takes the place of a Cross-Connect board.
  • No input or output ports (optical fibers) are wavelength assigned (i.e., colorless) and no additional space-switch matrices are required (i.e., port transparency).
  • FIG. 7 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using a IxN and an NxI WSS, which each provide N-add and N-drop channels for a total of 2N-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxN WSS, according to one embodiment of the invention. Note that the configurations are shown by way of examples, not by way of limitations, which each provides M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • Fig. 8 the configurations are shown by way of examples, not by way of limitations, which each provides M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add- Drop boards each using an NxI WSS and a IxM splitter, which each provides N-add and M-drop channels for a total of 2N-add and 2M-drop channels for this node.
  • N it will usually be desirable for N to be close to or equal to M.
  • Fig. 10 shows a degree-6 node with slot 7 and slot 8 populated with Add- Drop boards each using an MxI combiner and a IxM splitter, which each provides M-add and M-drop channels for a total of 2M-add and 2M-drop channels for this node, according to certain embodiments of the invention.
  • Fig. 11 shows a degree-6 node with slot 7 and slot 8 populated with Add- Drop boards each using a IxN and an NxI WSS, which each provides N-add and N- drop channels for a total of 2N-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxN WSS, which each provides M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • Fig. 12 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxN WSS, which each provides M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add-Drop boards each using an NxI WSS and a IxM splitter, which each provides N-add and M-drop channels for a total of 2N-add and 2M-drop channels for this node.
  • N N-add and M-drop channels for a total of 2N-add and 2M-drop channels for this node.
  • Fig. 14 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxM splitter, according to certain embodiments, which each provide M-add and M-drop channels for a total of 2M-add and 2M-drop channels for this node.
  • Fig. 15 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using a IxN and an NxI WSS, which each provide N-add and N-drop channels for a total of 2N-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxN WSS, which each provides M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • Fig. 15 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using a IxN and an NxI WSS, which each provide M-add and N-drop channels for a total of 2M-add and 2N-drop channels for this node.
  • a degree-6 node is depicted with slot 7 and slot 8 populated with Add- Drop boards each using an NxI WSS and a IxM splitter, according to one embodiment, which each provide N-add and M-drop channels for a total of 2N-add and 2M-drop channels for this node.
  • N N-add and M-drop channels for a total of 2N-add and 2M-drop channels for this node.
  • Fig. 18 shows a degree-6 node with slot 7 and slot 8 populated with Add-Drop boards each using an MxI combiner and a IxM splitter, which each provide M-add and M-drop channels for a total of 2M-add and 2M-drop channels for this node.
  • NxI WSS and IxN WSS modules used in an Add-Drop board to aggregate single wavelengths ( ⁇ -adds) or separate single wavelengths ( ⁇ - drops), respectively have a slightly different requirement in that each of the N fibers only contain a single wavelength. This differentiation provides an opportunity for a different technology to be employed, than the technology required for the WSS modules providing the optical cross-connect functionality.
  • An embodiment of the invention adds on the left and drops on the right as compared to the prior artwork that does the reverse, drops on the left and adds on the right.
  • laser transmitters connected to the input ports of the NxI WSS or MxI combiner of the Add-Drop boards may be selected to transmit on an arbitrary wavelength as long as it is not already in use by another transmitter connected to this Add-Drop board.
  • Another transmitter can operate at this similar or same wavelength as long as it is input by another Add-Drop board, according to certain embodiments of the invention, where the total number of common wavelengths is limited by the total number of Add-Drop boards employed at a given node.
  • the individual add channel wavelengths can be routed to any of the outputs going to remote nodes as long as that node output does not already have this channel wavelength in use.
  • a IxN WSS module that provides multicasting/broadcasting or a IxN splitter is employed
  • the same channel- wavelength signal can be routed to multiple outputs going to multiple remote nodes as long as those node outputs do not already have this channel wavelength in use.
  • This feature is a direct use of the port transparency of the add/drop system of this invention.
  • the added signals can be dropped locally and tested using the similar or same Add-Drop board or another Add-Drop board by passing through the optical cross connect.
  • received signals at this node can be routed arbitrarily to any of the output fibers of the IxN WSS or IxM splitter of the Add-Drop board for delivery to a receiver as long as that wavelength is not already in use for that Add-Drop board.
  • the number of simultaneous received signals at the same wavelength for a given node is limited to the number of Add-Drop boards placed in the chassis.
  • shown in Fig. 19 is a degree-5 node with slots 6 through 8 populated with Add-Drop boards that provide 3M-add and 3M-drop channels, where three of the same channel wavelengths can be used for add signals and also for drop signals.
  • the add-drop approach provides for call protection against failure of the active link pathway.
  • Shown in Fig. 20 is how a same- wavelength call and protection pathway is provided by having two Add-Drop boards at the call origination and destination nodes according to one embodiment, which provides for board- level disjointness at each node for greater network reliability.
  • the call pathway and protection pathway use two different wavelengths, which can be provided by having just a single Add-Drop board at the call origination and destination nodes. Examples of call failure this approach protects against are fiber cuts; total loss of power at an intermediate node or any catastrophic failure at that node; failure of source transmitter or destination receiver; or Add-Drop board failure at the source or destination node.
  • an Optical backplane is depicted in Fig. 22. Note that it can consist of one or more physically-separable fabric layers.
  • the backplane is an NxN shuffle, which means that signals entering the Optical backplane from each of the N slots can be routed passively to exit the Optical backplane at any of the N slots depending upon which of the N fibers are selected by the IxN WSS of a given slot. Signals can even be routed through the Optical backplane to exit the same board that launched the signal into the Optical backplane, which is known as loop back, according to certain embodiments of the invention.
  • the symmetry of the Optical backplane and the versatility of the WSS allow for every slot to be an equal in functionality.
  • the slots are redundant.
  • any embodiment/kind of CrossConnect or Add-Drop board functions with the same embodiment/implementation of the backplane.
  • the versatility of the backplane in conjunction with the versatility of the WSS-based boards provides for the following features, according to certain embodiments.
  • the optical system functions even when heavily depopulated. No additional channel wavelength blockage or contention occurs with the depopulation other than that related to the limited degree of the node or limitation posed by the number of Add-Drop boards as described above.
  • shown in Fig. 23 is a degree- 1 node with a single Add-Drop board populated in slot 2, which provides M-add and M-drop channels. This may be considered to be a network-termination node, since it provides for no pass through of signals other than loop back.
  • Fig. 24 shows a degree-2 node with slot 3 and slot 4 populated with Add- Drop boards, which provide 2M-add and 2M-drop channels according to certain embodiments of the invention. Note that this configuration is similar to what is known as an east- west reconfigurable add-drop multiplexer (ROADM); however, it does not have the deficiency of port assignment as conventional ROADMs have for adds/drops. Note that a single Add-Drop board would be sufficient.
  • the node may be populated in an arbitrary manner.
  • Fig. 25 shows this capability of arbitrary population and arrangement according to certain embodiments of the invention. Important in making use of this feature is the target specification that the boards be hot pluggable and unpluggable electrically in terms of the electrical high-speed signals and control signals the chassis and boards may use.
  • Colorless boards for signal creation and acquisition are needed to form a completely colorless optical communications system. Colorless means there is no wavelength assignment. We show how such boards should be made and how they should be interconnected with the Add-Drop boards. Transmitter-Receiver Boards
  • Transmitter- Receiver boards are shown in Fig. 26 and Fig. 27.
  • the thin line represents optical fibers containing a single wavelength channel.
  • the board depicted in Fig. 26 is sufficient.
  • the inherent wavelength-insensitive nature of photodetector receivers allows them to be used with an arbitrary, but single drop channel-wavelength signal.
  • Fig. 27 shows how a multi-fiber-optic patch-cord interconnects in a one- to-one manner the wavelength-tunable laser transmitters and the add ports, and between the single-wavelength drop channels and the wavelength-insensitive receivers.
  • Alternative signal manipulation boards may be based on optical-2R devices.
  • An optical-2R device does signal re-amplification and reshaping without the use of optical-to-electrical-to-optical (OEO) conversion as provided by laser transmitters and optical receivers.
  • Depicted in Fig. 30 is an Optical-2R board containing optical-2R devices with optional wavelength-conversion capability, according to one embodiment. Not shown are the tunable lasers each optical-2R device may employ.
  • Each optical-2R device has a single input wavelength channel ( ⁇ - drop) and outputs a single wavelength channel ( ⁇ -add).
  • Fig. 31 shows another possible Optical-2R board, according to another embodiment, which contains optical- 2R devices with optional wavelength-conversion capability.
  • a tunable filter selects a single wavelength channel from the multiplexed wavelength channels of each drop port, which is optically processed and produces a single wavelength channel ( ⁇ -add) output.
  • the Optical-2R boards connect with the Add-Drop boards using multi- fiber patch cords.
  • Fig. 32 shows explicitly a multi-fiber-optic patch-cord interconnection between the output of the individual wavelength-tunable optical-2R devices and the add ports formed by the MxI combiner of the Add-Drop board, and between the single-wavelength channel drops and the inputs of the optical-2R devices, according to one embodiment.
  • a tunable filter selects a single wavelength channel from the multiplexed wavelength channels of each drop port, which is optically processed and produces a single wavelength channel ( ⁇ -add) output.
  • Alien- Wavelength boards that contain tunable filters on the output ports of the IxM splitter, which causes only a single wavelength (the alien wavelength) to be returned to the client according to certain embodiments of the invention.
  • the patch cording required for Alien-Wavelength boards is quite straightforward, since the individual fibers are merely being connected to the client's transmitters and receivers. [0081] For the purposes of illustration, the level of detail was limited to illustrate only the critical functions and their relation among the various kinds of boards.
  • Fig. 35 gives a pictorial summary of Cross-Connect boards
  • Fig. 36 gives a pictorial summary of Add-Drop boards
  • Fig. 35 gives a pictorial summary of Cross-Connect boards
  • Fig. 36 gives a pictorial summary of Add-Drop boards
  • Fig. 37 gives a pictorial summary of Transmitter- Receiver boards
  • Fig. 38 gives a pictorial summary of Optical-2R boards
  • Fig. 39 gives a pictorial summary of Alien-Wavelength broads, where some also function as Add-Drop boards, according to some embodiments of the invention.
  • FIG. 4OA and Fig. 4OB shows certain embodiments of Dispersion-Managed Cross-Connect boards where the dispersion management is at the ingress.
  • Fig. 4OA gives placement of a multi-channel dispersion compensator (marked with the letter D) after the ingress optical amplifier (pre-amp, marked with a letter P), and
  • Fig. 40B gives placement of the multi-channel dispersion compensator (marked with the letter D) between the two stages of a possible two-stage ingress optical amplifier (pre-amps, marked Pl and P2).
  • Fig. 4OA gives placement of a multi-channel dispersion compensator (marked with the letter D) after the ingress optical amplifier (pre-amp, marked with a letter P)
  • Fig. 40B gives placement of the multi-channel dispersion compensator (marked with the letter D) between the two stages of a possible two-stage ingress optical amplifier (pre-amps, marked Pl and P2).
  • Fig. 4OA gives placement of a multi-channel dispersion compensator (marked
  • Fig. 42 shows certain embodiments of implementations of optical-channel monitoring on Cross-Connect boards, which covers monitoring of pass-through signals and signals added at this node.
  • Fig. 43 shows certain embodiments of implementations of optical- channel monitoring on Add- Drop boards, which covers monitoring of signals dropped at this node. Alien-wavelength signals also require monitoring for presence and optical power.
  • Fig. 44 shows the specific Alien-Wavelength boards with optical channel monitoring according to certain embodiments of the invention.
  • a tap coupler and multi-channel OCM could be placed after the pre-amp (P) but before the IxN WSS or IxN splitter instead of the approach taken in Figs. 42-44.
  • FIG. 45 shows one embodiment of node protection using a 3-dB splitter to send a copy of the ingress signals to an auxiliary Cross-Connect board and a 3-dB combiner to place the egress signals on the egress port of the slot with the failed Cross-Connect board, where an (N-I) xl space switch and a Ix (N-I) space switch together select which Cross-Connect board is under protected reroute.
  • Egress signals that were sent by any IxN WSSs to the failed Cross-Connect board need to be routed to the auxiliary Cross-Connect board. Note that transmission through the malfunctioning Cross-Connect board under protected reroute must be blocked by disabling the optical amplifiers, which makes them opaque.
  • FIG. 46 Another embodiment of node protection scheme shown in Fig. 46 uses a 1x2 space switch to reroute the ingress signals to an auxiliary Cross-Connect board and a 2x1 space switch to place the egress signals on the egress port of the slot with the failed Cross-Connect board, where an (N-I) xl space switch and a Ix (N-I) space switch together select which Cross-Connect board is under protected reroute. Egress signals that were sent by any IxN WSSs to the failed Cross-Connect board need to be routed to the auxiliary Cross-Connect board. Note that transmission is blocked through the malfunctioning Cross-Connect board under protection reroute by the 1x2 and 2x1 space switches, which have isolated the failed board from any possible signal transmission.
  • Fig. 47 Shown in Fig. 47 is a single chassis that is capable of handling all boards according to one embodiment, which we call a Super (i.e., main) chassis. It is a hybrid chassis containing an electrical-control backplane (Control backplane), a highspeed electrical- signal backplane (Electrical backplane), and an Optical backplane. Two separate chassis could also be used where one (as shown in Fig. 48 according to another embodiment) is an Optical chassis containing a electrical-control backplane (Control backplane) and an Optical backplane and the other (as shown in Fig.
  • a Super i.e., main
  • a hybrid chassis containing an electrical-control backplane (Control backplane), a highspeed electrical- signal backplane (Electrical backplane), and an Optical backplane.
  • Two separate chassis could also be used where one (as shown in Fig. 48 according to another embodiment) is an Optical chassis containing a electrical-control
  • 49 is an Electrical chassis containing an electrical- control backplane (Control backplane) and a high-speed electrical-signal backplane (Electrical backplane).
  • Electrical-control backplane Control backplane
  • Electrical-signal backplane Electric backplane
  • Cross-Connect, Add-Drop, Alien-Wavelength, Transmitter- Receiver, and Optical-2R boards would all go in the Super chassis.
  • Cross-Connect, Add-Drop, and Alien- Wavelength boards would go in the Optical chassis.
  • Transmitter-Receiver and Optical-2R boards would go in the Electrical chassis.
  • Optical-2R could go in the Optical chassis. Chassis Configurations
  • the (hybrid) Super chassis could be used alone or the (hybrid) Super chassis could be combined with an Electrical chassis at a later date to allow expansion of the number of Add-Drop signals at this node, which provides a future-upgrade option.
  • Fig. 51 shows an Optical chassis with one or more Electrical chassis to satisfy immediate need and again provide for future-upgrade expansion of the number of Add-Drop signals at this node according to another embodiment. Note that the Optical chassis does not possess a potentially expensive high-speed electrical backplane and the Electrical chassis does not possess a potentially expensive Optical backplane.
  • the utility of the (hybrid) Super chassis is shown by an example configuration in Fig.
  • FIG. 52 shows Cross Connect, Add-Drop, and Transmitter-Receiver boards, including the multi-fiber distribution patch cords that interconnect the Add- Drop and Transmitter- Receiver boards optically.
  • the Optical backplane is not used by the Transmitter-Receiver boards.
  • Fig. 53 shows another example configuration of a (hybrid) Super chassis with Cross Connect, Add-Drop, and Transmitter-Receiver boards.
  • the Optical backplane is not used by the Transmitter-Receiver board.
  • An example configuration of an Electrical chassis with Transmitter-Receiver and Optical-2R boards is shown in Fig. 54.
  • Fig. 54 An example configuration of an Electrical chassis with Transmitter-Receiver and Optical-2R boards is shown in Fig. 54. Fig.
  • FIG. 55 shows how the (hybrid) Super and Electrical chassis might be connected with multi-fiber distribution patch cords, which interconnect optically the Add-Drop boards with the Transmitter-Receiver or Optical-2R boards.
  • the Electrical chassis provides expansion for more Transmitter-Receiver or Optical-2R boards.
  • the Optical-2R board could have been placed in the (hybrid) Super chassis.
  • Shown in Fig. 56 is an example configuration of an Optical chassis according to one embodiment.
  • Fig. 57 shows how this Optical chassis of Fig. 56 and the Electrical chassis of Fig.
  • the issue that the one or more separate Electrical chassis deals with is the potential disparity between the numbers of required Transmitter- Receiver boards for every Add- Drop board. There may need to be far more Transmitter- Receiver boards per Add-Drop board. The number of transmitter and receiver pairs on a given Transmitter-Receiver board may be sparse, and much less than the integer M of adds/drops.
  • M it is desired for M to be large and up to the total number of dense- wavelength-division-multiplexed (DWDM) channels per fiber-optic link, such as possibly 40 channels when at 100 GHz spacing or 80 channels when at 50 GHz spacing as discussed earlier.
  • DWDM dense- wavelength-division-multiplexed
  • FIG. 58 Shown in Fig. 58 is a node configuration based on such a junior chassis that provides for at most an East- West ROADM capability. It could also be configured to degree 1, a terminating node, as depicted in Fig. 59 according to one embodiment.
  • Fig. 60 shows the down-sized control, electrical, and Optical backplanes of the junior chassis according to one embodiment.
  • the junior chassis is a hybrid chassis like the Super chassis, so is capable of accepting all types of boards, just less in number. Note that in this case a much simpler 3x3 optical shuffle is required for the Optical backplane as depicted in Fig. 61 according to one embodiment.
  • This implementation of a ROADM-like architecture exceeds the capabilities of a conventional ROADM because the transponders are not network-port assigned, which is an example of one of the inventions of this patent.
  • the following three figures give various embodiments of configurations of a (hybrid) Super chassis as a dedicated colorless Add-Drop chassis. They use alternatively three different possible specialized boards to make this add-drop system possible. We call these specialized boards Distribution- Aggregation boards.
  • the first two configurations also use specialized Single-Channel Transmitter- Receiver boards and specialized Single-Channel Optical-2R boards.
  • the third configuration uses specialized Multi-Channel Transmitter- Receiver boards and specialized Multi- Channel Optical-2R boards.
  • Fig. 62 shows chassis configured with a Distribution-Aggregation board based upon an NxI and a IxN WSS to provide a dedicated Add-Drop chassis, according to one embodiment which uses Single-Channel Transmitter-Receiver boards and Single-Channel Optical-2R boards.
  • Fig. 63 shows a chassis configured with a Distribution-Aggregation board based upon an NxI combiner and a IxN WSS to provide a dedicated Add-Drop chassis, according to one embodiment which uses Single-Channel Transmitter-Receiver boards and Single-Channel Optical-2R boards.
  • the IxN WSS on the Distribution-Aggregation board does the drop channel selection for each Single-Channel Transmitter- Receiver board or each Single- Channel Optical-2R board. Note that in all cases where a WSS module is responsible for working with a single wavelength for each of the N fibers, a different technology could be employed.
  • Fig. 64 shows a chassis configured with a Distribution- Aggregation board based upon a KxI combiner and a IxK splitter to provide a dedicated Add-Drop chassis, according to one embodiment which uses Multi-Channel Transmitter- Receiver boards and Multi-Channel Optical-2R boards.
  • the channel selection is made by the optical filter that occurs just before each receiver.
  • the integer value of K corresponds to the number of slots available for the signal manipulation boards, and J is limited by the maximum number of transmitters and receivers or optical-2R devices located on a single board.
  • Fig. 65 and Fig. 66 show two other various embodiments of implementations. Fig.
  • Fig. 65 shows a chassis configured with a Distribution- Aggregation board based upon a KxI combiner and a IxN WSS to provide a dedicated Add-Drop chassis, according to one embodiment which uses Multi-Channel Transmitter-Receiver boards and Multi-Channel Optical- 2R boards.
  • Fig. 66 shows a chassis configured with a Distribution- Aggregation board based upon an NxI WSS and a IxN WSS to provide a dedicated Add-Drop chassis, according to one embodiment which uses Multi-Channel Transmitter-Receiver boards and Multi-Channel Optical-2R boards.
  • the Optical backplane of the chassis routes the signals to the various Single-Channel or Multi-Channel Transmitter-Receiver boards. All of these specialized transmitter-receiver and optical-2R boards require the Distribution- Aggregation board be placed in a specific slot, which is slot 1 in the depicted embodiments. Node Configuration
  • FIG. 67 is one example configuration of an Optical chassis and an Add-Drop chassis, according to one embodiment with a single patch cord delivering multiplexed add signals to the input (ingress) of the Cross-Connect board of the Optical chassis from the output of the Distribution- Aggregation board of the Add-Drop chassis, and a single patch cord delivering multiplexed drop signals to the input of Distribution- Aggregation board of the Add-Drop chassis from the output (egress) of the Cross-Connect board of the Optical chassis.
  • a single patch cord delivering multiplexed add signals to the input (ingress) of the Cross-Connect board of the Optical chassis from the output of the Distribution- Aggregation board of the Add-Drop chassis from the output (egress) of the Cross-Connect board of the Optical chassis.
  • Fig. 68 shows another example configuration of an Optical chassis and an Add-Drop chassis, according to one embodiment with a single patch cord delivering multiplexed add signals to the input (ingress) of the Cross-Connect board of the Optical chassis from the output of the Distribution- Aggregation board of the Add- Drop chassis, and a single patch cord delivering multiplexed drop signals to the input of Distribution- Aggregation board of the Add-Drop chassis from the output (egress) of the Cross-Connect board of the Optical chassis. Summary of Specialized Boards
  • Fig. 69 gives a summary of Distribution- Aggregation boards according to certain embodiments of the invention.
  • Fig. 70 gives a summary of Single-Channel and Multi-Channel Transmitter- Receiver boards according to certain embodiments of the invention.
  • Fig. 71 gives a summary of Single-Channel and Multi-Channel Optical-2R boards according to certain embodiments of the invention.
  • An east-west ROADM is a potentially often needed type of configuration. As shown earlier in Fig. 24, Fig. 52 (but with only two Cross-Connect boards), and Fig. 58, the chassis with two Cross-Connect boards form the east and west connections of an east-west ROADM.
  • the chassis with two Cross-Connect boards form the east and west connections of an east-west ROADM.
  • other specialized transmitter-receiver and optical-2R boards are possible to make an Expanded East- West ROADM when using a (hybrid) Super chassis, where these boards are colorless and port transparent.
  • These boards also provide the additional feature that no fiber-optic patch cords for add or drop signals are required as in other configurations. All add and drop signals are routed through the Optical backplane.
  • Fig. 72 shows an Expanded East- West ROADM that has a 1x2 space switch to select the east or west egress for the add signal, and has a 2x1 space switch to accept the east or west ingress drop signal as delivered by the IxN WSS according to one embodiment.
  • Fig. 72 shows an Expanded East- West ROADM that has a 1x2 space switch to select the east or west egress for the add signal, and has a 2x1 space switch to accept the east or west ingress drop signal as delivered by the IxN WSS according to one embodiment.
  • Fig. 73 shows another example of an Expanded East- West ROADM that has a 1x2 splitter to broadcast the add signal where the NxI WSS selects the east or west egress for the add signal, and has a 2x1 combiner to accept the east or west ingress drop signal as delivered by the IxN WSS according to one embodiment.
  • Fig. 74 shows another example of an Expanded East- West ROADM that has a 1x2 splitter to broadcast the add signal where the NxI WSS selects the east or west egress for the add signal, and has a 2x1 space switch to accept the east or west ingress drop signal as delivered by the IxN WSS according to one embodiment.
  • Fig. 74 shows another example of an Expanded East- West ROADM that has a 1x2 splitter to broadcast the add signal where the NxI WSS selects the east or west egress for the add signal, and has a 2x1 space switch to accept the east or west ingress drop signal as delivered by
  • FIG. 75 shows another example of an Expanded East- West ROADM that has a 1x2 space switch to select the east or west egress for the add signal, and has a 2x1 combiner to accept the east or west ingress drop signal as delivered by the IxN WSS according to one embodiment.
  • IxN WSS & NxI Combiner Cross-Connect Boards there may be another type of CrossConnect board may also be used to make an Expanded East- West ROADM, which is a Cross-Connect board based on a IxN WSS and an NxI combiner. There are two compatible East- West Transmitter- Receiver boards and only two compatible East- West Optical-2R boards.
  • Fig. 76 shows the case of an Expanded East- West ROADM that has a 1x2 space switch to select the east or west egress for the add signal, and has a 2x1 space switch to accept the east or west ingress drop signal as delivered by the IxN WSS.
  • Fig. 77 shows the case of an Expanded East- West ROADM that has a 1x2 space switch to select the east or west egress for the add signal, and has a 2x1 combiner to accept the east or west ingress drop signal as delivered by the IxN WSS.
  • Fig. 78 gives a summary of the East- West Transmitter-Receiver boards and Fig. 79 gives a summary of the East- West Optical-2R boards according to certain embodiments. All of these specialized transmitter-receiver and optical-2R boards require the Cross-Connect boards be placed in specific slots, which are slots 1 and 2 in the depicted embodiments. Other configurations may exist.
  • the full Optical backplane shown in Fig. 22 is not entirely used. The opportunity exists to use a depopulated Optical backplane.
  • the full backplane may consist of multiple fabric layers, where on the necessary ones are installed for the Add-Drop chassis and the
  • Optical backplane The direction of the arrows only indicates the direction the channel-wavelength signals propagate when the Optical backplanes are used.
  • Bold lines indicate the possibility of two or more multiplexed channel- wavelength signals.
  • Fig. 80 Shown in Fig. 80 is the simplified Optical backplane fabric required for the
  • Add-Drop chassis shown in Figs. 62 through and including 66 This fabric may be a single layer of the full fabric shown in Fig. 22. Note that if such a simplified Optical backplane were to be used, the chassis would no longer be a Super chassis, but indeed a dedicated Add-Drop chassis.
  • Fig. 81 Shown in Fig. 81 is the simplified Optical backplane fabric required for the
  • This fabric may be two layers of the full fabric shown in
  • Fig. 22 Note that if such a simplified Optical backplane were to be used, the chassis would no longer be a Super chassis, but a specialized Expanded East- West ROADM chassis.
  • Embodiments of the present invention also relate to an apparatus for performing the operations herein.
  • This apparatus may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer.
  • a computer program may be stored in a computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), erasable programmable ROMs (EPROMs), electrically erasable programmable ROMs (EEPROMs), magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.
  • ROMs read-only memories
  • RAMs random access memories
  • EPROMs erasable programmable ROMs
  • EEPROMs electrically erasable programmable ROMs
  • magnetic or optical cards or any type of media suitable for storing electronic
  • a machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computer).
  • a machine-readable medium includes read only memory ("ROM”); random access memory (“RAM”); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.); etc.
  • ROM read only memory
  • RAM random access memory
  • magnetic disk storage media includes magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.); etc.

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Abstract

L'invention concerne un système de communications modulaire basé WSS comportant des interfaces sans couleur à port réseau transparent. Selon certains aspects de l'invention, une architecture d'équipement rend possible l'existence d'un réseau optique linéaire, annulaire ou maillé. Les modes de réalisation de l'invention concernent en premier lieu la façon d'insérer et d'extraire des signaux au niveau d'un noeud du réseau. Ces modes de réalisation sont basés sur l'utilisation d'un commutateur à sélection de longueurs d'onde (WSS), ce qui représente une technologie émergente des composants. L'invention concerne également d'autres procédés et dispositifs.
PCT/US2008/078034 2008-09-26 2008-09-26 Système de communications modulaire basé wss comportant des interfaces à insertion/extraction sans couleur WO2010036268A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN200880000284A CN101809912A (zh) 2008-09-26 2008-09-26 具有无色插入/分出接口的基于模块化wss的通信系统
PCT/US2008/078034 WO2010036268A1 (fr) 2008-09-26 2008-09-26 Système de communications modulaire basé wss comportant des interfaces à insertion/extraction sans couleur

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2445129A1 (fr) * 2010-10-19 2012-04-25 Alcatel Lucent Multiplexeur optique d'insertion/extraction
EP2574076A1 (fr) * 2011-09-22 2013-03-27 Alcatel Lucent Noeud optique pour commuter les signaux entre les fibres optiques
WO2017074653A1 (fr) * 2015-10-27 2017-05-04 Nec Laboratories America, Inc. Protection redondante pour unité de branchement à multiplexage d'insertion/extraction optique reconfigurable (roadm)
US20210273740A1 (en) * 2019-03-20 2021-09-02 Tencent Technology (Shenzhen) Company Limited Reconfigurable optical add-drop multiplexer, optical network, and optical signal processing method

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3008837B1 (fr) 2013-06-11 2019-03-27 Telefonaktiebolaget LM Ericsson (publ) Surveillance de la sécurité pour réseau optique
CN104363045A (zh) * 2014-11-19 2015-02-18 天津光电通信技术有限公司 具有信号调理功能的智能波长选择光交叉系统
US10448128B2 (en) * 2016-01-29 2019-10-15 National University Corporation Nagoya University Optical switch device
US10805698B2 (en) * 2016-03-08 2020-10-13 National University Corporation Tokai National Higher Education And Research System Optical cross-connect device
US9692511B1 (en) * 2016-03-28 2017-06-27 Mellanox Technologies, Ltd. Redundant and reconfigurable optical transceiver
US10028040B1 (en) * 2017-04-21 2018-07-17 Lumentum Operations Llc Colorless, directionless, contentionless optical network using MxN wavelength selective switches
JP7138530B2 (ja) * 2018-10-02 2022-09-16 三菱電機株式会社 光クロスコネクト装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6973229B1 (en) * 2001-02-28 2005-12-06 Lambda Opticalsystems Corporation Node architecture for modularized and reconfigurable optical networks, and methods and apparatus therefor
US20070014510A1 (en) * 2005-07-15 2007-01-18 Hitachi Communication Technologies, Ltd. Optical network equipment and optical network
US20080056715A1 (en) * 2006-08-30 2008-03-06 Fujitsu Limited Optical transmission apparatus having OADM function

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6973229B1 (en) * 2001-02-28 2005-12-06 Lambda Opticalsystems Corporation Node architecture for modularized and reconfigurable optical networks, and methods and apparatus therefor
US20070014510A1 (en) * 2005-07-15 2007-01-18 Hitachi Communication Technologies, Ltd. Optical network equipment and optical network
US20080056715A1 (en) * 2006-08-30 2008-03-06 Fujitsu Limited Optical transmission apparatus having OADM function

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2445129A1 (fr) * 2010-10-19 2012-04-25 Alcatel Lucent Multiplexeur optique d'insertion/extraction
EP2574076A1 (fr) * 2011-09-22 2013-03-27 Alcatel Lucent Noeud optique pour commuter les signaux entre les fibres optiques
WO2013041456A1 (fr) * 2011-09-22 2013-03-28 Alcatel Lucent Nœud optique pour une commutation de signaux entre des fibres optiques
KR101521839B1 (ko) * 2011-09-22 2015-05-27 알까뗄 루슨트 광섬유들 사이의 신호들을 스위칭하기 위한 광 노드
US9203542B2 (en) 2011-09-22 2015-12-01 Alcatel Lucent Optical node for switching signals between optical fibers
WO2017074653A1 (fr) * 2015-10-27 2017-05-04 Nec Laboratories America, Inc. Protection redondante pour unité de branchement à multiplexage d'insertion/extraction optique reconfigurable (roadm)
US20210273740A1 (en) * 2019-03-20 2021-09-02 Tencent Technology (Shenzhen) Company Limited Reconfigurable optical add-drop multiplexer, optical network, and optical signal processing method
US11909514B2 (en) * 2019-03-20 2024-02-20 Tencent Technology (Shenzhen) Company Limited Reconfigurable optical add-drop multiplexer, optical network, and optical signal processing method

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