EP1304013A2 - Modularer optischer netzwerkknoten - Google Patents
Modularer optischer netzwerkknotenInfo
- Publication number
- EP1304013A2 EP1304013A2 EP01953890A EP01953890A EP1304013A2 EP 1304013 A2 EP1304013 A2 EP 1304013A2 EP 01953890 A EP01953890 A EP 01953890A EP 01953890 A EP01953890 A EP 01953890A EP 1304013 A2 EP1304013 A2 EP 1304013A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- functionality
- network node
- optical network
- optical
- circuit
- Prior art date
- Legal status (The legal status 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 status listed.)
- Withdrawn
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 81
- 238000000034 method Methods 0.000 claims description 6
- 238000005215 recombination Methods 0.000 claims 1
- 230000006798 recombination Effects 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 description 8
- 239000000835 fiber Substances 0.000 description 5
- 230000002457 bidirectional effect Effects 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 230000000903 blocking effect Effects 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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
- H04J14/0206—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
- 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
- H04Q2011/0009—Construction using wavelength filters
-
- 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
- H04Q2011/0007—Construction
- H04Q2011/0035—Construction using miscellaneous components, e.g. circulator, polarisation, acousto/thermo optical
-
- 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
- H04Q2011/0037—Operation
- H04Q2011/0041—Optical control
-
- 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
- H04Q2011/0037—Operation
- H04Q2011/0047—Broadcast; Multicast
-
- 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
- H04Q2011/0037—Operation
- H04Q2011/005—Arbitration and scheduling
-
- 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
- H04Q11/0062—Network aspects
- H04Q2011/0075—Wavelength grouping or hierarchical aspects
Definitions
- the invention relates to a modular optical Netztechnikkno ⁇ th, which can make an interconnection of optical signals on Subbandbasis and a method for transmitting optical signals in the optical network devices on this modular optical network nodes.
- Optical networks use the wide available bandwidth (> 10 THz for single-mode fibers) of glass fibers for message transmission. For an effective use of the available transmission capacity, the entire bandwidth is appropriately further divided. This is usually accomplished in systems with high transmission capacity through the use of wavelength division multiplexers, i.e. by transmitting different channels on different optical carrier wavelengths.
- the transmission of information based on optical networks typically takes place through a hierarchical network structure.
- the transitions between the individual hierarchy levels are guaranteed via network nodes.
- network nodes are also necessary for the establishment of meshed network topologies of the same hierarchy level.
- Network nodes can also be used so that optical network elements can access certain wavelengths or wavelength ranges.
- there are network nodes with different functionality e.g. OADMs, i.e. optical add-drop multiplexers, .ring interconnects or optical cross-connects).
- optical network nodes were used to convey information or to access information or both in combination.
- Optical multiplex bundle switches (OXC, ie optical cross-connections) are used, which carry out a switching on a wavelength basis.
- OXC optical multiplex bundle switches
- wavelength switching based on individual wavelengths leads to very complex solutions for switching concepts and the construction of optical network nodes if large transmission capacities with a high number of channels are required.
- Non-blocking multiplex bundle switches require a large number of optical switches with the desired high number of channels, which complicate the technical feasibility and also cause considerable costs.
- the wavelength pattern of the channels is fixed by the multiplexers and demultiplexers in the optical switching nodes. An adaptation to e.g. Different types of fibers or an expansion by increasing the number of channels is therefore difficult.
- the object of the invention is therefore to provide a flexible and low-effort implementation of a modular optical network node for the transmission of information and / or data
- a modular optical network node which comprises at least one module for selecting subbands and the module for selecting subbands has at least one preselection device for preselecting at least one optical subband, at least one subband multiplexing device and at least one subband demultiplexing device and additionally at least one Central element is provided.
- the preselection device is preferably used to divide the available optical bandwidth of an optical signal.
- the module for selecting subbands is made possible by the preselection device and the at least one subband demultiplexing device to select subbands of an available optical bandwidth, and to convey them via at least one central element and to process them further as required.
- the preselection device for preselecting at least one optical subband is designed in such a way that the subband structure or division of the available optical bandwidth into individual subbands can be determined or predetermined.
- the preselection device can divide the optical bandwidth into subbands on the basis of a predefined setting.
- the preselection device is particularly preferably configurable, ie the determinability of the subbands by the preselection device can be changed.
- the preselection device is very particularly preferably remotely configurable. There are two preferred options: In centrally controlled networks, remote configurability can be achieved via a network management system using a software solution.
- the preselection device can then be implemented by a software solution in network management and correspond to values in tables which are forwarded to the demultiplex device or the filter arrangement arranged there in order to preselect the physical manipulated variables in such a way that the available optical bandwidth can be divided into the predetermined subbands is.
- the preselection device is very particularly preferably a storage device in which values can be stored which correspond to the corresponding subband divisions.
- the preselection devices can be configured remotely by means of an intelligence which is present in each preselection device itself. These preselection devices can then be reconfigured using suitable protocols. ö tr rt tr P cn cn ⁇ sQ P ⁇ g cn Hi rt ö P ö
- P. P- ⁇ ⁇ d P «O ⁇ ⁇ rt tS! ⁇ ⁇ -i P ⁇ cn SP 1-5 ⁇ l iQ Q ⁇ OP? tu H ⁇ P- XP ) P cn ⁇ P- d 0 ⁇ 1 3 P. ⁇ ⁇ HH ⁇ P 1 rt li d li P g O ⁇ P- cn fr li o ö
- the number of subbands to be processed can be increased in combinations.
- the functionality of the modular optical network node can be expanded by adding individual central elements.
- the modular optical network node can be used for conveying information or for accessing information or both in combination. It allows use as an OADM, ring interconnect or OXC. It is particularly preferably used in typical hierarchical network structures consisting of meshed or ring-shaped wide area networks, ring networks for the metro area and tree-shaped network topologies in the access area.
- the modular optical network nodes or some components of the modular optical network node are designed in duplicate in order to ensure the protection of the optical paths and of the network elements.
- the functionalities of the central elements of the modular optical network node can be different. Then a scalable, modular optical network node with different central elements is created. Different compositions of the modular optical network nodes through the modules for the selection of subbands with central elements of different functionality allow the basic expansion of the functionalities of the network nodes.
- the modular optical network node optionally comprises one or more optical switching stages, as well as several subband demultiplexing devices or subband multiplexing devices, depending on the number of incoming and outgoing fibers and the maximum subbander to be switched.
- P d tr P P P- tr ⁇ P- P P P O P d tu ⁇ rt P- d ⁇ hj tr tr ⁇ ⁇ N tr cn h- "P P P sQ ⁇ P to p- p- P P O
- rial or erbium-doped waveguide can amplify the signals.
- the add-drop multiplexer for bidirectional networks described in FIG. 2 can also be used in unidirectional networks.
- FIG. 3 shows the same structure as in FIG. 2. Only the central elements ZEn, ZEn have been changed, which comprise a circuit with drop-continue functionality or with multicast functionality.
- the circuits consist of a room switching stage with drop-and-continue capability.
- the central elements ZEn, ZEm allow a wavelength or a sub-band to be extracted in the node and a new wavelength or band to be added (add-drop functionality).
- the incoming subbands can particularly preferably be routed on the one hand to the add-drop stage ADSn, ADSm and at the same time forwarded to the output fiber without a new subband being added (multicast / broadcast functionality, drop-and-continue functionality).
- Different implementations and a different structure can be used for the switching stage.
- Switching matrices are particularly preferred as the switching stage, in which the number of switching elements can be reduced, e.g. Switching matrices according to CLOS and BENES. Depending on the type and use, the switching matrices can be selected to be strictly non-blocking or not strictly non-blocking.
- the modular optical network node MON described in FIG. 3 with drop-and-continue functionality for bidirectional networks can also be used in unidirectional networks.
- FIG. 4 shows the use of a modular network node as a ring interconnect. It is now the construction groups for selecting subbands BAU1 - BAU4. Each module divides the available optical bandwidth VOS into subbander SB. Each of the subbands is processed by a central element.
- FIG. 4 shows the processing of a subband per assembly for the selection of subbands BAU1 - BAU4 by a central element ZE1 - ZE4.
- Each of the central elements ZE1 - ZE4 of the respective modules for selecting subbands BAU1 - BAU4 has a room switching stage. The room switching stages particularly preferably have drop-and-continue capability.
- the room switching stages are connected to one another in such a way that a central element ZE1 of the first module for selecting subbands BAU1 is connected to the module for selecting subbands BAU3 and a central element ZE3 of the module for selecting subbands BAU3 is connected to the module for selecting subbands BAU1 , Furthermore, a central element ZE2 of the module for selecting subbands B ⁇ IT2 is connected to the module for selecting subbands BAU4, and a central element ZE4 of the module for selecting subbands BAU4 is connected to the module for selecting subbands BAU2.
- a ring interconnect can particularly preferably have further central elements which represent combinations of the central elements ZE1-ZE4
- the ring interconnect very particularly preferably has a central element switching stage ZES.
- the ring interconnect described in FIG. 4 for bidirectional networks can also be used in unidirectional networks.
- Figure 5 illustrates the use of a modular optical network node MON as a cross-connect this case are four construction ⁇ group for selection of sub-bands progress1 -. BAU4 shown.
- the respective central elements of the module for selecting subbands BAU1 - BAU4 are shown as a central element switching stage ZES.
- the central element switching stage ZES has a switching matrix which can be constructed, for example, with micromechanical switches, integrated optical switches, liquid crystal switches and enables the subbands to be switched between the incoming and outgoing fibers. In addition to a pure switching property, the switching matrix can also have drop-and-continue or multicast or add-drop options.
- the cross-connect described in FIG. 5 for bidirectional networks can also be used in unidirectional networks.
- the invention relates to a modular optical network node that divides optical input signals into optical subbands, processes them through a central element or a plurality of central elements, and then recombines the optical subbands into an optical output signal.
- the central element or the central elements of the modular optical network node can have various functionalities, such as an add-drop functionality, a drop-and-continue functionality, a multicast functionality, a broadcast functionality, a ring interconnect functionality and a cross -Connect functionality. Depending on the assignment one
- the modular optical network node can be used in networks with different structures.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Communication System (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
Abstract
Description
Claims
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE10036700 | 2000-07-27 | ||
| DE10036700A DE10036700A1 (de) | 2000-07-27 | 2000-07-27 | Modularer optischer Netzwerkknoten |
| PCT/DE2001/002552 WO2002011489A2 (de) | 2000-07-27 | 2001-07-09 | Modularer optischer netzwerkknoten |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP1304013A2 true EP1304013A2 (de) | 2003-04-23 |
Family
ID=7650463
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP01953890A Withdrawn EP1304013A2 (de) | 2000-07-27 | 2001-07-09 | Modularer optischer netzwerkknoten |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US20030128985A1 (de) |
| EP (1) | EP1304013A2 (de) |
| DE (1) | DE10036700A1 (de) |
| WO (1) | WO2002011489A2 (de) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8971706B2 (en) | 2001-10-01 | 2015-03-03 | Rockstar Consortium Us Lp | Link discovery, verification, and failure isolation in an optical communication system |
| US6999681B2 (en) * | 2002-01-23 | 2006-02-14 | Pts Corporation | Method of seamless migration from static to agile optical networking |
| US6868201B1 (en) * | 2002-03-22 | 2005-03-15 | Nortel Networks Limited | Reconfigurable WDM mux/demux/OADM |
| US6853763B1 (en) * | 2002-03-27 | 2005-02-08 | Nortel Networks Limited | Photonic switching including photonic pass-through and add/drop capabilities |
| US7894418B2 (en) * | 2002-08-15 | 2011-02-22 | The Boeing Company | Mixed analog and digital chip-scale reconfigurable WDM network |
| US20040052530A1 (en) * | 2002-09-17 | 2004-03-18 | Cechan Tian | Optical network with distributed sub-band rejections |
| WO2004028999A2 (de) * | 2002-09-23 | 2004-04-08 | Basf Aktiengesellschaft | Dünne filme oxidischer materialien mit hoher dielektrizitätskonstante |
| WO2004036801A1 (de) * | 2002-10-15 | 2004-04-29 | Adva Ag Optical Networking | Optischen add/drop-multiplexer und ringstruktur zur datenübertragung mittels eines optischen wellenlängenmultiplexe-systems |
| US7483636B2 (en) * | 2003-07-28 | 2009-01-27 | Fujitsu Limited | Optical network with sub-band rejection and bypass |
| US7444078B1 (en) * | 2003-09-18 | 2008-10-28 | At&T Intellectual Property Ii, L.P. | Transient control solution for optical networks |
| US20050095001A1 (en) * | 2003-10-29 | 2005-05-05 | Fujitsu Limited | Method and system for increasing network capacity in an optical network |
| US20050196169A1 (en) * | 2004-03-03 | 2005-09-08 | Fujitsu Limited | System and method for communicating traffic between optical rings |
| US20070003283A1 (en) * | 2005-06-29 | 2007-01-04 | At&T Corp. | Dynamic allocation of bandwidth in a bidirectional optical transmission system |
| US7200299B1 (en) * | 2006-03-23 | 2007-04-03 | Lucent Technologies Inc. | Adding and dropping wavelength-channels |
| US20070280688A1 (en) * | 2006-04-21 | 2007-12-06 | Matisse Networks | Upgradeable optical hub and hub upgrade |
| US7970244B2 (en) | 2006-09-11 | 2011-06-28 | The Boeing Company | Fabrication of an optical ring resonator device |
| WO2016165111A1 (zh) * | 2015-04-16 | 2016-10-20 | 华为技术有限公司 | 一种分插复用器和分插复用器中信号处理的方法 |
| GB2551328B (en) * | 2016-06-10 | 2020-02-19 | Bluwireless Tech Ltd | Clock synchronisation in wireless mesh communications networks |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19605808C2 (de) * | 1996-02-16 | 1997-12-18 | Siemens Ag | WDM-Koppelanordnung |
| US6052399A (en) * | 1997-08-29 | 2000-04-18 | Xerox Corporation | Independently addressable laser array with native oxide for optical confinement and electrical isolation |
| JP4031853B2 (ja) * | 1997-10-20 | 2008-01-09 | 富士通株式会社 | 双方向光通信用光伝送装置 |
| KR100400362B1 (ko) * | 1998-08-04 | 2003-11-14 | 삼성전자주식회사 | 광결합및분리장치,그리고 이를구비한파장분할다중화광링크 |
| CA2289322A1 (en) * | 1998-12-10 | 2000-06-10 | Nortel Networks Corporation | Multi-channel optical add/drop multiplexor/demultiplexor |
| AU2001286385A1 (en) * | 2000-05-15 | 2001-11-26 | Corning Incorporated | Optical networking devices and methods for optical networks with increased transparency |
-
2000
- 2000-07-27 DE DE10036700A patent/DE10036700A1/de not_active Withdrawn
-
2001
- 2001-07-09 WO PCT/DE2001/002552 patent/WO2002011489A2/de not_active Ceased
- 2001-07-09 EP EP01953890A patent/EP1304013A2/de not_active Withdrawn
- 2001-07-09 US US10/343,271 patent/US20030128985A1/en not_active Abandoned
Non-Patent Citations (1)
| Title |
|---|
| See references of WO0211489A2 * |
Also Published As
| Publication number | Publication date |
|---|---|
| US20030128985A1 (en) | 2003-07-10 |
| WO2002011489A2 (de) | 2002-02-07 |
| WO2002011489A3 (de) | 2002-06-27 |
| DE10036700A1 (de) | 2002-02-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| 17P | Request for examination filed |
Effective date: 20030109 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: SCHEERER, CHRISTIAN Inventor name: GLINGENER, CHRISTOPH Inventor name: ELBERS, JOERG-PETER |
|
| RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: GLINGENER, CHRISTOPH Inventor name: SCHEERER, CHRISTIAN, DR. Inventor name: ELBERS, JOERG-PETER |
|
| RBV | Designated contracting states (corrected) |
Designated state(s): DE FR GB IT |
|
| RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: NOKIA SIEMENS NETWORKS GMBH & CO. KG |
|
| RAP3 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: NOKIA SIEMENS NETWORKS S.P.A. |
|
| RAP3 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: NOKIA SIEMENS NETWORKS GMBH & CO. KG |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN |
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| 18W | Application withdrawn |
Effective date: 20080312 |