WAVELENGTH PATH COMMUNICATION NODE APPARATUS, WAVELENGTH PATH COMMUNICATION CONTROL METHOD, PROGRAM, AND RECORDING MEDIUM

• US 20110116790A1
• Filed: 05/22/2009
• Published: 05/19/2011
• Est. Priority Date: 05/26/2008
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Nakamura, Shigeru, Fukuchi, Kiyoshi, Sakauchi, Masahiro, Nishioka, Itaru, Urino, Yutaka
• Granted Patent: US 8,693,880 B2
• Time in Patent Office: Days
• US Class Current: 398/5
• CPC Class Codes: H04J 14/0204 Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or dropping
• CPC Class Codes: H04J 14/0209 Multi-stage arrangements, e.g. by cascading multiplexers or demultiplexers
• CPC Class Codes: H04J 14/021 Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM]
• CPC Class Codes: H04J 14/0212 using optical switches or wavelength selective switches [WSS]
• CPC Class Codes: H04J 14/0213 Groups of channels or wave bands arrangements
• CPC Class Codes: H04J 14/0217 Multi-degree architectures, e.g. having a connection degree greater than two
• CPC Class Codes: H04J 14/0219 Modular or upgradable architectures
• CPC Class Codes: H04J 14/0254 Optical medium access
• CPC Class Codes: H04J 14/0257 Wavelength assignment algorithms
• CPC Class Codes: H04J 14/0258 Wavelength identification or labelling
• CPC Class Codes: H04J 14/0269 using tables for routing
• CPC Class Codes: H04J 14/0284 WDM mesh architectures
• CPC Class Codes: H04J 14/0297 Optical equipment protection
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0015 using splitting combining
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• CPC Class Codes: H04Q 2011/0024 using space switching
• CPC Class Codes: H04Q 2011/0052 Interconnection of switches
• CPC Class Codes: H04Q 2011/0073 Provisions for forwarding or routing, e.g. lookup tables
• CPC Class Codes: H04Q 2011/0079 : Operation or maintenance aspects
• CPC Class Codes: H04Q 2213/1301 : Optical transmission, optical switches
• CPC Class Codes: H04Q 2213/13295 : Wavelength multiplexing, WDM

Abstract

A wavelength path communication node apparatus includes a wavelength path demultiplexer (321) which demultiplexes branched optical signals input to wavelength multiplexing ports into wavelength path signals, and outputs the wavelength path signals from wavelength demultiplexing ports corresponding to the respective wavelengths, a wavelength path multiplexer (322) which outputs wavelength path signals input to wavelength demultiplexing ports from wavelength multiplexing ports corresponding to the wavelengths of the wavelength path signals, a plurality of transponders (331) each of which converts a wavelength path signal input to a wavelength path transmission port into a client transmission signal to transmit the client transmission signal, and converts a received client reception signal into a wavelength path signal of a wavelength to output the wavelength path signal from a wavelength path reception port, a demultiplexing system optical matrix switch (323) which switches and connects the wavelength demultiplexing ports of the wavelength path demultiplexer and the wavelength path transmission ports of the transponders, and a multiplexing system optical matrix switch (324) which switches and connects the wavelength demultiplexing ports of the wavelength path multiplexer and the wavelength path reception ports of the transponders.

Claims

1. A wavelength path communication node apparatus that is used in an optical communication network in which respective traffics are assigned by a wavelength division multiplexing transmission method to a plurality of wavelength paths for performing data communication using optical signals having unique wavelengths, wavelength path signals of the wavelength paths are multiplexed into one optical signal, and the optical signal is transmitted via wavelength multiplexing transmission lines, and that switches and connects the wavelength path between the wavelength multiplexing transmission lines, the apparatus comprising:

a plurality of optical branching couplers which are arranged for the respective wavelength multiplexing transmission lines, and each of which branches power of an optical signal received from the wavelength multiplexing transmission line into a plurality of branched optical signals;

a plurality of multiplexing system wavelength selection switches which are arranged for the respective wavelength multiplexing transmission lines, and each of which selects wavelength path signals of arbitrary wavelengths from the plurality of branched optical signals branched by said optical branching couplers, multiplexes the wavelength path signals into one optical signal, and transmits the optical signal to the wavelength multiplexing transmission line;

a wavelength path demultiplexer which includes a plurality of wavelength multiplexing ports that are arranged for said respective optical branching couplers and receive the branched optical signals from said optical branching couplers, and a plurality of wavelength demultiplexing ports whose connection correspondence with the wavelength multiplexing ports is uniquely determined by a wavelength, and which demultiplexes the branched optical signals input to the wavelength multiplexing ports into wavelength path signals of respective wavelengths, and outputs the wavelength path signals from the wavelength demultiplexing ports corresponding to the respective wavelengths;

a wavelength path multiplexer which includes a plurality of wavelength multiplexing ports that are arranged for said respective multiplexing system wavelength selection switches and output wavelength path signals of at least one wavelength to said multiplexing system wavelength selection switches, and a plurality of wavelength demultiplexing ports whose connection correspondence with the wavelength multiplexing ports is uniquely determined by a wavelength, and which outputs wavelength path signals input to the wavelength demultiplexing ports from the wavelength multiplexing ports corresponding to wavelengths of the wavelength path signals;

a plurality of transponders each of which includes a wavelength path transmission port and a wavelength path reception port, is connected to a client apparatus that performs data communication using a wavelength path of one wavelength, converts a wavelength path signal input to the wavelength path transmission port into a client transmission signal to transmit the client transmission signal to the client apparatus, and converts a client reception signal received from the client apparatus into a wavelength path signal of the wavelength to output the wavelength path signal from the wavelength path reception port;

a demultiplexing system optical matrix switch which switches and connects the wavelength demultiplexing ports of said wavelength path demultiplexer and the wavelength path transmission ports of said transponders; and

a multiplexing system optical matrix switch which switches and connects the wavelength demultiplexing ports of said wavelength path multiplexer and the wavelength path reception ports of said transponders.

2. A wavelength path communication node apparatus according to claim 1, further comprising:

a plurality of client accommodation functional units each including said wavelength path demultiplexer, said wavelength path multiplexer, said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said transponder; and

a plurality of demultiplexing system wavelength selection switches which are arranged for said respective optical branching couplers, and each of which outputs a branched optical signal from said optical branching coupler to the wavelength multiplexing port of said wavelength path demultiplexer included in one of said client accommodation functional units.

3. A wavelength path communication node apparatus according to claim 1, further comprising a client system optical matrix switch which switches and connects said respective transponders and a plurality of client apparatuses.

4. A wavelength path communication node apparatus according to claim 1, further comprising:

a node controller which controls switching of said multiplexing system wavelength selection switches, said demultiplexing system optical matrix switch, and said multiplexing system optical matrix switch, assigns a wavelength path of one wavelength to said transponder, and acquires a fault generation notification from a counter transponder detected by said transponder;

a transponder information table which stores, for an identification number of each transponder, connection port numbers of said demultiplexing system optical matrix switch and said multiplexing system optical matrix switch to which said transponder is connected, a transmission line number of the wavelength multiplexing transmission line on which an operating system wavelength path of said transponder is multiplexed, and a wavelength number indicating a wavelength of the operating system wavelength path; and

a port correspondence table which stores, for a wavelength number indicating a wavelength of each wavelength path, a correspondence between a transmission line number of the wavelength multiplexing transmission line connected to each wavelength multiplexing port and a port number of the wavelength demultiplexing port as the connection correspondences in said wavelength path demultiplexer and said wavelength path multiplexer,

wherein when setting the operating system wavelength path of said transponder, said node controller looks up said transponder information table to acquire the transmission line number, the wavelength number, and the connection port number regarding the operating system wavelength path of said transponder, looks up said port correspondence table to specify port numbers indicating the wavelength demultiplexing ports of said wavelength path multiplexer and said wavelength path demultiplexer corresponding to the transmission line number and the wavelength number, and controls switching of said demultiplexing system optical matrix switch and said multiplexing system optical matrix switch to connect the wavelength demultiplexing port of the port number specified from said port correspondence table and a connection port of the connection port number acquired from said transponder information table.

5. A wavelength path communication node apparatus according to claim 4, wherein

said transponder information table further stores, for the identification number of each transponder, a transmission line number of the wavelength multiplexing transmission line on which a spare system wavelength path of said transponder is multiplexed, and a wavelength number indicating a wavelength of the spare system wavelength path, and

when said node controller detects generation of a fault on a wavelength path from the fault generation notification detected by said transponder, said node controller looks up said transponder information table to acquire the transmission line number, the wavelength number, and the connection port regarding the spare system wavelength path of said transponder, looks up said port correspondence table to specify port numbers indicating the wavelength demultiplexing ports of said wavelength path multiplexer and said wavelength path demultiplexer corresponding to the transmission line number and the wavelength number, and controls switching of said demultiplexing system optical matrix switch and said multiplexing system optical matrix switch to connect the wavelength demultiplexing port of the port number specified from said port correspondence table and the connection port of a connection port number acquired from said transponder information table.

6. A wavelength path communication node apparatus according to claim 3, further comprising:

a node controller which controls switching of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch, assigns a wavelength path of one wavelength to said transponder, and detects generation of a fault in said transponder; and

a transponder information table which stores, for an identification number of each transponder, an identification number of a spare system transponder assigned as a spare system of said transponder, and connection port numbers of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch to which said spare system transponder is connected,

wherein when said node controller detects generation of a fault in said transponder which operates as an operating system, said node controller looks up said transponder information table to acquire the identification number of said spare system transponder regarding said operating system transponder, and connection port numbers of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch regarding said spare system transponder, and controls switching of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch to connect connection ports of the connection port numbers and said spare system transponder.

7. A wavelength path communication node apparatus according to claim 3, further comprising:

a plurality of client accommodation functional units each including said wavelength path demultiplexer, said wavelength path multiplexer, said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch, one of said client accommodation functional units serving as an operating system client accommodation functional unit used as an operating system, and another one of said client accommodation functional units serving as a spare system client accommodation functional unit used as a spare system;

an aggregator system switching optical switch which is interposed between said wavelength path demultiplexer, said wavelength path multiplexer, and said transponders, and switches and connects said operating system client accommodation functional unit and said spare system client accommodation functional unit;

a pool system switching optical switch which is interposed between said transponders and said client system optical matrix switch, and switches and connects said operating system client accommodation functional unit and said spare system client accommodation functional unit; and

a client system switching optical switch which is interposed between said client system optical matrix switch and the client apparatus, and switches and connects said operating system client accommodation functional unit and said spare system client accommodation functional unit.

8. A wavelength path communication node apparatus according to claim 7, further comprising:

a node controller which controls switching of said demultiplexing system wavelength selection switch, said multiplexing system wavelength selection switch, said demultiplexing system optical matrix switch, and said multiplexing system optical matrix switch included in said client accommodation functional unit, and detects generation of a fault in said wavelength path demultiplexer, said wavelength path multiplexer, said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch; and

a switching state storage unit which stores switching states of said demultiplexing system optical matrix switch, multiplexing system optical matrix switch, and client system optical matrix switch of said operating system client accommodation functional unit,

wherein when said node controller detects generation of a fault in one of said wavelength path demultiplexer, said wavelength path multiplexer, said demultiplexing system optical matrix switch, and said multiplexing system optical matrix switch included in said operating system client accommodation functional unit, said node controller sets switching states of said demultiplexing system optical matrix switch and multiplexing system optical matrix switch of said spare system client accommodation functional unit, based on the switching states acquired from said switching state storage unit, and controls switching of said demultiplexing system wavelength selection switch, said multiplexing system wavelength selection switch, and said aggregator system switching optical switch to set a wavelength path between said transponder and the multiplexing transmission line via said spare system client accommodation functional unit, and

when said node controller detects generation of a fault in said client system optical matrix switch included in said operating system client accommodation functional unit, said node controller sets a switching state of said client system optical matrix switch of said spare system client accommodation functional unit, based on the switching states acquired from said switching state storage unit, and controls switching of said pool system switching optical switch and said client system switching optical matrix switch to set a wavelength path between said transponder and the client apparatus via said spare system client accommodation functional unit.

9. A wavelength path communication node apparatus according to claim 7, further comprising:

a node controller which controls switching of said demultiplexing system wavelength selection switch, said multiplexing system wavelength selection switch, said demultiplexing system optical matrix switch, and said multiplexing system optical matrix switch included in said client accommodation functional unit, and detects generation of a fault in said transponder; and

a transponder information table which stores, for an identification number of each transponder, an identification number of a spare system transponder assigned as a spare system of said transponder, and connection port numbers of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch to which said spare system transponder is connected,

wherein when generation of a fault in said transponder included in said operating system client accommodation functional unit is detected, said transponder information table is looked up to acquire an identification number of said spare system transponder regarding said operating system transponder, and connection port numbers of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, and said client system optical matrix switch regarding said spare system transponder, and switching of said demultiplexing system optical matrix switch, said multiplexing system optical matrix switch, said client system optical matrix switch, said aggregator system switching optical switch, and said pool system switching optical switch is controlled to connect connection ports of the connection port numbers and said spare system transponder.

10. A wavelength path communication node apparatus according to claim 1, further comprising, instead of said transponder, a wavelength path signal transmitter which converts a wavelength path signal input to a wavelength path transmission port into a client transmission signal and transmits the client transmission signal to the client apparatus, and a wavelength path signal receiver which converts a client reception signal received from the client apparatus into a wavelength path signal of the wavelength and outputs the wavelength path signal from a wavelength path reception port.

11. A wavelength path communication control method used in a wavelength path communication node apparatus that is used in an optical communication network in which respective traffics are assigned by a wavelength division multiplexing transmission method to a plurality of wavelength paths for performing data communication using optical signals having unique wavelengths, wavelength path signals of the wavelength paths are multiplexed into one optical signal, and the optical signal is transmitted via wavelength multiplexing transmission lines, and that switches and connects the wavelength path between the wavelength multiplexing transmission lines, the method comprising the steps of:

causing each of optical branching couplers arranged for the respective wavelength multiplexing transmission lines to branch power of an optical signal received from the wavelength multiplexing transmission line into a plurality of branched optical signals;

causing each of multiplexing system wavelength selection switches arranged for the respective wavelength multiplexing transmission lines to select wavelength path signals of arbitrary wavelengths from the plurality of branched optical signals branched by the optical branching couplers, multiplex the wavelength path signals into one optical signal, and transmit the optical signal to the wavelength multiplexing transmission line;

causing a wavelength path demultiplexer including a plurality of wavelength multiplexing ports that are arranged for the respective optical branching couplers and receive the branched optical signals from the optical branching couplers, and a plurality of wavelength demultiplexing ports whose connection correspondence with the wavelength multiplexing ports is uniquely determined by a wavelength, to demultiplex the branched optical signals input to the wavelength multiplexing ports into wavelength path signals of respective wavelengths, and output the wavelength path signals from the wavelength demultiplexing ports corresponding to the respective wavelengths;

causing a wavelength path multiplexer including a plurality of wavelength multiplexing ports that are arranged for the respective multiplexing system wavelength selection switches and output wavelength path signals of at least one wavelength to the multiplexing system wavelength selection switches, and a plurality of wavelength demultiplexing ports whose connection correspondence with the wavelength multiplexing ports is uniquely determined by a wavelength, to output wavelength path signals input to the wavelength demultiplexing ports from the wavelength multiplexing ports corresponding to wavelengths of the wavelength path signals;

causing a plurality of transponders each including a wavelength path transmission port and a wavelength path reception port, to connect to a client apparatus that performs data communication using a wavelength path of one wavelength, convert a wavelength path signal input to the wavelength path transmission port into a client transmission signal, thereby transmitting the client transmission signal to the client apparatus, and convert a client reception signal received from the client apparatus into a wavelength path signal of the wavelength, thereby outputting the wavelength path signal from the wavelength path reception port;

causing a demultiplexing system optical matrix switch to switch and connect the wavelength demultiplexing ports of the wavelength path demultiplexer and the wavelength path transmission ports of the transponders; and

causing a multiplexing system optical matrix switch to switch and connect the wavelength demultiplexing ports of the wavelength path multiplexer and the wavelength path reception ports of the transponders.

12. A computer-readable recording medium which records a program for causing, to execute the steps of a wavelength path communication control method defined in claim 11, a computer of a wavelength path communication node apparatus that is used in an optical communication network in which respective traffics are assigned by a wavelength division multiplexing transmission method to a plurality of wavelength paths for performing data communication using optical signals having unique wavelengths, wavelength path signals of the wavelength paths are multiplexed into one optical signal, and the optical signal is transmitted via wavelength multiplexing transmission lines, and that switches and connects the wavelength path between the wavelength multiplexing transmission lines.

13. (canceled)