CN1859061B - Method for improving optical layer protective reliability of wave division multiplex system - Google Patents
Method for improving optical layer protective reliability of wave division multiplex system Download PDFInfo
- Publication number
- CN1859061B CN1859061B CN2006100333838A CN200610033383A CN1859061B CN 1859061 B CN1859061 B CN 1859061B CN 2006100333838 A CN2006100333838 A CN 2006100333838A CN 200610033383 A CN200610033383 A CN 200610033383A CN 1859061 B CN1859061 B CN 1859061B
- Authority
- CN
- China
- Prior art keywords
- optical
- signal
- protection
- wavelength
- client layer
- 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.)
- Active
Links
Images
Landscapes
- Optical Communication System (AREA)
Abstract
This invention discloses a method for increasing the reliability of optical protection of WDM system, which judges on the basis of the test result on the service performance the customer layer of the single wavelength signal receiving unit, multi-wavelength signal receive unit or high priority wavelength signal receiving unit to trigger the switch state of the optical switch connecting a working channel and a protection channel to realize optical layer protection switch, which uses the character information of the customer layer to monitor the network quality taken as the base of protection starting so as to switch protection channels reliably.
Description
Technical field
The present invention relates to field of communication transmission, refer to a kind of being applicable in the optical-fiber network transmission especially, improve the method for wave division multiplexing WDM system optical layer protective reliability.
Background technology
Development along with the Internet and customer service; optical-fiber network need carry a lot of signal wavelengths; along with the raising of user to professional and network quality, reliability requirement; a lot of operations commercial city requires WDM (wavelengthDivision Multiplexing; wavelength division multiplexing) system can provide the protection of photosphere face to switch; to guarantee that business also can be moved normally under the situation that fibre circuit, the network equipment or other aspects go wrong.
In wdm system, use following protected mode usually: dedicated optical path protection, shared Optical Channel Protection, optical multiplexing section protection etc.Because wdm system need guarantee the transparency of network for business; and optical switch is transparently (as can insert 2.5G, 10G, 40G business etc. pellucidly for business; then ordinary business practice is opaque based on the switch of electricity), therefore many times all adopt optical switch protection to switch.Simultaneously, when the WDM network is switched in the protection of carrying out the photosphere face, need to judge exactly immediately the state of performance of services and monitoring network, therefore the reliability that the protection mission is switched has higher requirement.
Prior art related to the present invention adopts the protection of wavelength conversion unit, splitter/optical switch realization dual transmitting and receiving function to switch as shown in Figure 1.Wherein, the optical branching device of 1:1 is divided into two-way with the signal of wavelength conversion unit output, sends into service aisle and protection passage respectively; At the opposite end receiver side; optical switch receives the signal from service aisle and protection passage simultaneously; optical switch changes by the difference of the luminous power of two inputs of detection; if changing, difference surpasses a certain predefined threshold value; protection takes place optical switch switches, the signal that the receiver selective reception protection passage of wavelength conversion unit transmits.
Another prior art related to the present invention as shown in Figure 2, optical branching device and optical switch are connected between equipment and the fibre circuit, realize the dual transmitting and receiving function of circuit.Optical branching device was divided into two-way with signal before light signal is sent to optical fiber; one the tunnel is sent to service aisle; other one the tunnel is sent to the protection passage; at the opposite end receiver side; optical switch is by comparing the optical power change of two optical-fibre channel inputs; come state of a control, the light signal of light signal in order to the selective reception service aisle or protection passage.
In existing technical scheme; because when changing appears in the luminous power of service aisle and protection passage; problem may not necessarily take place in signal quality; or under a lot of situations; when the input optical power of two ports of optical switch does not change, but signal quality deterioration (a large amount of error codes for example occurred, but luminous power being normal); therefore greatly reduce the reliability of system because the protected mode of prior art is based on the variation of comparison luminous power this moment.Simultaneously, because the signal of service aisle and protection passage is when arriving optical switch, signal power can not equate fully, and therefore in order to simplify or convenient, it is equal substantially to need to use attenuator that the power adjustments of two ports is arrived usually, has increased the cost of system.
Summary of the invention
The invention provides the method for a kind of raising wavelength division multiplexing (WDM) system optical layer protective reliability, start the insecure problem of switching of protecting in the prior art in order to solve.
The invention provides the method for a kind of raising wavelength division multiplexing (WDM) system optical layer protective reliability; optical wavelength conversion element OTU in this method detects the wavelength through the input signal of optical switch; switch trigger condition with the client layer service feature testing result that wavelength was carried as protection; trigger the protection of optical switch and switch, finish service protection and switch.
Described optical layer protective is Optical Channel Protection or optical multiplexing section protection.
Described client layer service feature testing result can be a single wavelength signal institute carrying client layer service performance test results; Or, the majority voting result of a plurality of wavelength institute carrying client layer service performance test results; Or, the other wavelength of high priority institute carrying client layer service performance test results.
Described Optical Channel Protection is, optical switch comprises two inputs and an output, and wherein two inputs connect service aisle and protection passage respectively, and output links to each other with the client layer signal receiving element.
During described Optical Channel Protection was switched, the client layer signal receiving element was transformed into the signal of telecommunication with light signal, simultaneously the performance of monitoring light signals.
The performance of described light signal comprises: for the SDH signal, out-of-limit for the B1 error code, the B2 error code is out-of-limit, the optical wavelength input optical power is low excessively, the input signal Loss of continuity; For ethernet signal, for CRC check mistake, packet loss, input signal Loss of continuity, input optical power low excessively; For the OTN signal, for the FEC error correction, error code is out-of-limit, luminous power is low excessively, the luminous power Loss of continuity; For the pos frame signal, out-of-limit for the B1 error code, the optical wavelength input optical power is low excessively, the input signal Loss of continuity.
Supervision predetermined threshold value to described optical signal property; The performance number of the described light signal of service aisle that the client layer signal receiving element receives has exceeded predefined threshold value, and then optical switch is carried out switching action, will protect the light signal of passage to be sent to the client layer signal receiving element.
Described optical multiplexing section protection is, the light signal of one or more wavelength enters wave multiplexer and closes Lu Weiyi road light signal, enters optical branching device then, is divided into two ways of optical signals, and one the tunnel enters service aisle, and other one the tunnel enters the protection passage; Two inputs of optical switch connect service aisle and protection passage respectively, simultaneously the light signal in the service aisle are sent to channel-splitting filter, and channel-splitting filter is sent to corresponding client layer signal receiving element respectively with the light signal of separating.
In the described optical multiplexing section protection, the client layer signal receiving element is transformed into the signal of telecommunication with light signal, simultaneously the performance of monitoring light signals.
The performance of described light signal comprises: for the SDH signal, out-of-limit for the B1 error code, the B2 error code is out-of-limit, the optical wavelength input optical power is low excessively, the input signal Loss of continuity; For ethernet signal, for CRC check mistake, packet loss, input signal Loss of continuity, input optical power low excessively; For the OTN signal, for the FEC error correction, error code is out-of-limit, luminous power is low excessively, the luminous power Loss of continuity; For the pos frame signal, out-of-limit for the B1 error code, the optical wavelength input optical power is low excessively, the input signal Loss of continuity.
Supervision predetermined threshold value to described optical signal property; The performance number of the described light signal of service aisle that the client layer signal receiving element receives has exceeded predefined threshold value, and then optical switch is carried out switching action, will protect the light signal of passage to be sent to the client layer signal receiving element.
Described optical multiplexing section protection is; one the tunnel or the performance number of the service aisle light signal that receives of multiple signals receiving element exceeded predefined described threshold value; then optical switch is carried out switching action, and the light signal in the protection passage is sent to the client layer signal receiving element.
Described optical multiplexing section protection is, the single or a plurality of signal receiving units of same website and the optical switch of this website are set to same optical multiplexing section protection group, and the optical switch in the described protection group is controlled by the interior signal receiving unit of this group.
Wavelength signals in the described protection group is N, be provided with M (when the light signal of individual wavelength of M＜=N) performance occurs and exceeds threshold value, the switching action of optical switch execute protection; Or the wavelength signals in the described protection group is N, N wavelength is provided with different priority levels, or (M＜=N), every group has different priority levels, and when other wavelength performance of high priority exceeded threshold value, the optical switch execute protection was switched to be divided into M group.
Beneficial effect of the present invention is as follows:
Adopt the method for wdm system optical layer protective reliability provided by the invention; luminous power appearance variation when service aisle and protection passage; and signal quality is not when having problem; or the input optical power of working as two ports of optical switch does not change; but signal quality is under the situation of deterioration; utilize the client layer characteristic information to come the foundation of monitoring network quality situation and conduct protection startup, thereby protect the switching of passage reliably, solved the problem of optical layer protective shortage monitoring capacity.Simultaneously, owing to needn't use attenuator, reduced the cost of system.
Description of drawings
Fig. 1 is the Optical Channel Protection schematic diagram based on optical switch;
Fig. 2 is the optical multiplexing section protection schematic diagram based on optical switch;
Fig. 3 is the Optical Channel Protection schematic diagram based on optical switch of embodiment one provided by the invention;
Fig. 4 is the optical multiplexing section protection schematic diagram based on optical switch of embodiment two provided by the invention;
Fig. 5 is the optical multiplexing section protection schematic diagram of a plurality of websites provided by the invention.
Embodiment
Specific embodiment one: utilize optical branching device/optical switch to realize the Optical Channel Protection that detects based on the client layer service feature, specific implementation as shown in Figure 3:
Optical wavelength OTU (optical transponder unit; converting unit) Shu Chu flashlight; optical branching device by correspondence is divided into two-way respectively; one the tunnel enters the MUX (multiplexer of service aisle; optical multiplexer); other one the tunnel enters the MUX of protection passage; after closing ripple, enter service aisle respectively and protect passage to arrive the DEMUX unit (demultiplexer of opposite end receiver side; the light demultiplexer); DEMUX separates light signal the unit, sends into each self-corresponding optical switch through operation wavelength passage and protection wavelength channel.
Under the normal operation, optical switch connects service aisle, signal enters the receiving terminal of OTU through optical switch, receiving terminal changes light signal into the signal of telecommunication, and the service feature that monitors input signal in the OTU unit that continues can detect for the SDH signal whether the B1 error code is out-of-limit, whether the B2 error code is out-of-limit, whether the optical wavelength input optical power is low excessively, whether the input signal continuity loses etc.; For ethernet signal, can detect the CRC check mistake, whether whether packet loss, input signal continuity lose, input optical power is whether low excessively etc.; For the OTN signal, can detect the FEC error correction, whether error code is out-of-limit, whether luminous power is low excessively, whether the luminous power continuity loses etc.; For the pos frame signal, can monitor whether the B1 error code is out-of-limit, whether the optical wavelength input optical power is low excessively, whether the input signal continuity loses etc.Which the client layer signal performance parameter is on earth, can be according to different signal type decisions.
Be provided with protection to the time; OTU is set to a protection group with the corresponding optical switch that is connected this OTU unit; can regulation start basis for estimation and judgment criterion and the threshold value that protection is switched; protect switching action as out-of-limit then startup of the B1 error code that the OTU unit can be set; in case the OTU unit continues to detect the B1 error code; and error code out-of-limit (surpassing the threshold value that sets in advance) appears; control unit will be notified in the OTU unit this moment; performance degradation appears in service wavelength; after control unit receives instruction; realize switching by optical switch, switch to the protection passage, this moment, the OTU unit received the signal of protection passage input.
Optical switch in the technical program is just realized toggle path, need not the comparison luminous power.Certainly, the also luminous power of monitor protection passage and service aisle wavelength simultaneously of the optical switch in the technical program.
Specific embodiment two: utilize optical branching device/optical switch to realize the optical multiplexing section protection that detects based on the client layer service feature, specific implementation as shown in Figure 4:
At transmitting terminal; the signal of OTU output is sent to MUX and closes ripple; enter optical branching device then; be divided into two paths of signals; one the tunnel enters service aisle, and other one the tunnel enters the protection passage, arrives the opposite end receiver side; work main signal and protection main signal enter two inputs that receive optical switch respectively, send into corresponding OTU receiving port along separate routes by DMUX then.
For the optical multiplexing section protection that a plurality of websites (when there is the OADM website centre) arranged, the position of optical branching device and optical switch as shown in Figure 5:
A has about a plurality of wavelength to the B website, A has about a plurality of wavelength to the C website, B has about a plurality of wavelength to C, all there is optical switch in receiving terminal at A, B, C website, but configuration protection to the time, receiving terminal OTU and optical switch that need each website be set to one group, as: the receiving terminal OUT at B station is set to one group with the optical switch at the B website; The receiving terminal OUT at C station is set to one group with the optical switch at the C website, if B website business up and down breaks down, has only the optical switch protection of B website receiving terminal to switch; If C website business up and down breaks down, have only the optical switch protection of C website to switch, and the optical switch of B website is failure to actuate.
Set after the protection group, the client layer service feature that the connection status and the OTU of optical switch received connects, and can detect for the SDH signal whether the B1 error code is out-of-limit, whether the B2 error code is out-of-limit, whether the optical wavelength input optical power is low excessively, whether the input signal continuity loses etc.; For ethernet signal, can detect the CRC check mistake, whether whether packet loss, input signal continuity lose, input optical power is whether low excessively etc.; For the OTN signal, can detect the FEC error correction, whether error code is out-of-limit, whether luminous power is low excessively, whether the luminous power continuity loses etc.; For the pos frame signal, can monitor whether the B1 error code is out-of-limit, whether the optical wavelength input optical power is low excessively, whether the input signal continuity loses etc.Which the client layer signal performance parameter is on earth, can be according to different signal type decisions.
For optical multiplexing section protection, owing to a lot of wavelength are arranged by optical switch, but not all wavelength all is to occur service feature deterioration or other problem simultaneously, is that example describes with Fig. 4, need add judgment mechanism and strategy among a plurality of wavelength signals.Among Fig. 2, the business that 5 wavelength are arranged in this protection group, when setting performance degradation occurs as the wavelength business that (comprises 3) more than 3, the optical switch execute protection is switched, as for the SDH signal, can detect that the B1 error code is out-of-limit, the B2 error code is out-of-limit, the optical wavelength input optical power is low excessively, input signal Loss of continuity etc.; Also can set when having only a wavelength business performance degradation to occur, optical switch protection is switched.
In a WDM network, may there be a lot of wavelength business between the website, the priority level of these wavelength business is different, set the priority level of wavelength business, for example among Fig. 4, if wavelength 1 is other business of limit priority, wavelength 2 is other business of high medium priority, wavelength the 3,4, the 5th, other business of low priority, when if wavelength 1 business goes out existing performance degradation so, even performance degradation does not appear in other business, network also starts protection to be switched, and guarantees the normal operation of the business of limit priority; Perhaps work as wavelength 3,4 and performance degradation occurred, but other wavelength business are no problem, network not execute protection is switched, with the influence that guarantees that wavelength 1 (high-priority service) is not switched by network protection.
Optical switch in the technical program is just realized toggle path, need not the comparison luminous power.Certainly, the also luminous power of monitor protection passage and service aisle wavelength simultaneously of the optical switch in the technical program.
Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.
Claims (14)
1. method that improves optical layer protective reliability of wave division multiplex system; it is characterized in that; optical wavelength conversion element OTU detects the wavelength through the input signal of optical switch; switch trigger condition with the client layer service feature testing result that described wavelength was carried as protection; trigger the protection of optical switch and switch, finish service protection and switch.
2. the method for claim 1 is characterized in that, described optical layer protective is Optical Channel Protection or optical multiplexing section protection.
3. the method for claim 1 is characterized in that,
Described client layer service feature testing result can be a single wavelength signal institute carrying client layer service performance test results; Or,
The majority voting result of a plurality of wavelength institute carrying client layer service performance test results; Or,
The other wavelength of high priority institute carrying client layer service performance test results.
4. method as claimed in claim 2; it is characterized in that described Optical Channel Protection is that optical switch comprises two inputs and an output; wherein two inputs connect service aisle and protection passage respectively, and output links to each other with the client layer signal receiving element.
5. method as claimed in claim 4 is characterized in that, during described Optical Channel Protection was switched, the client layer signal receiving element was transformed into the signal of telecommunication with light signal, simultaneously the performance of monitoring light signals.
6. method as claimed in claim 5 is characterized in that, the performance of described light signal comprises:
For the SDH signal, out-of-limit for the B1 error code, the B2 error code is out-of-limit, the optical wavelength input optical power is low excessively, the input signal Loss of continuity;
For ethernet signal, for CRC check mistake, packet loss, input signal Loss of continuity, input optical power low excessively;
For the OTN signal, for the FEC error correction, error code is out-of-limit, luminous power is low excessively, the luminous power Loss of continuity;
For the pos frame signal, out-of-limit for the B1 error code, the optical wavelength input optical power is low excessively, the input signal Loss of continuity.
7. method as claimed in claim 6 is characterized in that, to the supervision predetermined threshold value of described optical signal property; The performance number of the described light signal of service aisle that the client layer signal receiving element receives has exceeded predefined threshold value, and then optical switch is carried out switching action, will protect the light signal of passage to be sent to the client layer signal receiving element.
8. method as claimed in claim 2 is characterized in that described optical multiplexing section protection is, the light signal of one or more wavelength enters wave multiplexer and closes Lu Weiyi road light signal, enters optical branching device then, is divided into two ways of optical signals, one the tunnel enters service aisle, and other one the tunnel enters the protection passage; Two inputs of optical switch connect service aisle and protection passage respectively, simultaneously the light signal in the service aisle are sent to channel-splitting filter, and channel-splitting filter is sent to corresponding client layer signal receiving element respectively with the light signal of separating.
9. method as claimed in claim 8 is characterized in that, in the described optical multiplexing section protection, the client layer signal receiving element is transformed into the signal of telecommunication with light signal, simultaneously the performance of monitoring light signals.
10. method as claimed in claim 9 is characterized in that, the performance of described light signal comprises:
For the SDH signal, out-of-limit for the B1 error code, the B2 error code is out-of-limit, the optical wavelength input optical power is low excessively, the input signal Loss of continuity;
For ethernet signal, for CRC check mistake, packet loss, input signal Loss of continuity, input optical power low excessively;
For the OTN signal, for the FEC error correction, error code is out-of-limit, luminous power is low excessively, the luminous power Loss of continuity;
For the pos frame signal, out-of-limit for the B1 error code, the optical wavelength input optical power is low excessively, the input signal Loss of continuity.
11. method as claimed in claim 10 is characterized in that, to the supervision predetermined threshold value of described optical signal property; The performance number of the described light signal of service aisle that the client layer signal receiving element receives has exceeded predefined threshold value, and then optical switch is carried out switching action, will protect the light signal of passage to be sent to the client layer signal receiving element.
12. method as claimed in claim 10; it is characterized in that; described optical multiplexing section protection is; one the tunnel or the performance number of the service aisle light signal that receives of multiple signals receiving element exceeded predefined threshold value; then optical switch is carried out switching action, and the light signal in the protection passage is sent to the client layer signal receiving element.
13. method as claimed in claim 8; it is characterized in that; described optical multiplexing section protection is; single or a plurality of signal receiving units of same website and the optical switch of this website are set to same optical multiplexing section protection group, and the optical switch in the described protection group is controlled by the signal receiving unit in this group.
14. method as claimed in claim 13 is characterized in that,
Wavelength signals in the described protection group is N, be provided with M (when the light signal of individual wavelength of M＜=N) performance occurs and exceeds threshold value, the switching action of optical switch execute protection;
Or the wavelength signals in the described protection group is N, N wavelength is provided with different priority levels, or (M＜=N), every group has different priority levels, and when other wavelength performance of high priority exceeded threshold value, the optical switch execute protection was switched to be divided into M group.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006100333838A CN1859061B (en) | 2006-01-24 | 2006-01-24 | Method for improving optical layer protective reliability of wave division multiplex system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006100333838A CN1859061B (en) | 2006-01-24 | 2006-01-24 | Method for improving optical layer protective reliability of wave division multiplex system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1859061A CN1859061A (en) | 2006-11-08 |
| CN1859061B true CN1859061B (en) | 2011-04-20 |
Family
ID=37297928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2006100333838A Active CN1859061B (en) | 2006-01-24 | 2006-01-24 | Method for improving optical layer protective reliability of wave division multiplex system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1859061B (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101321031B (en) | 2008-07-16 | 2011-12-07 | 中兴通讯股份有限公司 | Sharing protection method and system for wavelength division multiplexing looped network |
| CN103188577B (en) * | 2011-12-27 | 2016-09-07 | 中国移动通信集团黑龙江有限公司 | A kind of stand-by channel monitoring method, Apparatus and system |
| CN103957536B (en) * | 2014-05-14 | 2017-03-15 | 烽火通信科技股份有限公司 | Wireless access network system based on C RAN |
| CN104618057B (en) * | 2014-12-31 | 2016-05-11 | 国网山东省电力公司青岛供电公司 | A kind of Packet Transport Network not damaged protection reverse method and system |
| CN105227279A (en) * | 2015-10-19 | 2016-01-06 | 中国航空无线电电子研究所 | A kind of Redundancy Management system for dual-fiber-channel network communicating system |
| CN111596409B (en) * | 2019-02-20 | 2022-08-30 | 阿里巴巴集团控股有限公司 | Optical transmission system, scheduling node, multiplexing node, and demultiplexing node |
| CN115065895A (en) * | 2019-06-29 | 2022-09-16 | 华为技术有限公司 | Protection switching device and method |
| CN114124287A (en) * | 2020-08-31 | 2022-03-01 | 华为技术有限公司 | Optical signal control method and device, optical transmission node and optical transmission system |
| CN115694617A (en) * | 2021-07-28 | 2023-02-03 | 中兴通讯股份有限公司 | Protection switching method and electronic equipment |
| CN115021803A (en) * | 2022-06-02 | 2022-09-06 | 中国电信股份有限公司 | Optical channel protection method, device and system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004095746A1 (en) * | 2003-04-23 | 2004-11-04 | Siemens Aktiengesellschaft | Protection switching and monitoring method and arrangement in a data transmission system |
| CN1713555A (en) * | 2004-06-24 | 2005-12-28 | 华为技术有限公司 | Light channel shared protection control and its controller |
-
2006
- 2006-01-24 CN CN2006100333838A patent/CN1859061B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004095746A1 (en) * | 2003-04-23 | 2004-11-04 | Siemens Aktiengesellschaft | Protection switching and monitoring method and arrangement in a data transmission system |
| CN1713555A (en) * | 2004-06-24 | 2005-12-28 | 华为技术有限公司 | Light channel shared protection control and its controller |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1859061A (en) | 2006-11-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1859061B (en) | Method for improving optical layer protective reliability of wave division multiplex system | |
| US7174096B2 (en) | Method and system for providing protection in an optical communication network | |
| US8615169B2 (en) | PON system and redundancy method | |
| EP2051442B9 (en) | Method, system and apparatus for protecting wavelength division multiplex transmission | |
| JP4593267B2 (en) | Optical node and optical add / drop multiplexer | |
| CN101826919B (en) | Mixed type passive optical network structure and method for positioning and restoring faults thereof | |
| CA2455640A1 (en) | Protection switching architecture and method of use | |
| CN102811094B (en) | Protective changeover device of wave division-time division multiplexing passive optical network system and method | |
| US6697546B2 (en) | Optical node system and switched connection method | |
| JP3740969B2 (en) | Optical cross-connect device | |
| JP4728697B2 (en) | Optical switch device and optical access network method and optical access network system using the same | |
| US6798991B1 (en) | Optical communication systems, optical communication system terminal facilities, optical communication methods, and methods of communicating within an optical network | |
| CN104393914A (en) | A multiplex route recovering method for an optical fiber differential protection device | |
| US20050238361A1 (en) | Optical transponder with equipment failure protection | |
| CN104202082B (en) | A kind of high survivability PON protection structure of low overhead | |
| US7715715B2 (en) | Shared optical ring protection in a multi-fiber ring | |
| JP5558220B2 (en) | Node device for optical network system | |
| US20130028592A1 (en) | Apparatus and method for switching paths in a wavelength-multiplexing network | |
| AU769923B2 (en) | Method and system for communication protection | |
| CN100568815C (en) | A kind of system for transmitting single-fiber-optic two-way wavelength division multiplexing and guard method thereof | |
| CN100508439C (en) | Light channel shared protection control and its controller | |
| Uehara et al. | Highly reliable and economical WDM ring with optical self-healing and 1: N wavelength protection | |
| EP2234329A1 (en) | The method and device for protecting the shared channel in the optical transmission system | |
| EP2517390B1 (en) | Method and device for data protection in an optical communication network | |
| CN102457329A (en) | Passive optical network architecture and protection method and optical switch structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |