CN1254035C - Light wavelength channel protecting method and apparatus for compact WDM system - Google Patents
Light wavelength channel protecting method and apparatus for compact WDM system Download PDFInfo
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- CN1254035C CN1254035C CN 02144172 CN02144172A CN1254035C CN 1254035 C CN1254035 C CN 1254035C CN 02144172 CN02144172 CN 02144172 CN 02144172 A CN02144172 A CN 02144172A CN 1254035 C CN1254035 C CN 1254035C
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Abstract
The present invention relates to a method and a device for protecting a light wavelength channel of a multiway multiplexing system applied to a dense wavelength division multiplexing system. The present invention is characterized in that in the dense wavelength division multiplexing, a multiplexer (MUX) can additionally connect with an additional multiplexer, and light signals output by the multiplexer (MUX) and a backup wavelength adjustable optical transform unit (OTU) output are combined and output through the additional multiplexer; the additional multiplexer and a relevant demultiplexer (DEMUX) adopt the optical transform unit (OTU) as a backup protecting unit for a system optical wavelength channel; the demultiplexer (DEMUX) can correspondingly and additionally connect with a demultiplexer to receive signals transmitted by the additional multiplexer; the additional multiplexer and the additional demultiplexer adopt the wavelength adjustable optical transform unit (OTU) as the backup protecting unit of the system optical wavelength channel. The present invention has a high utilization rate of system wavelength resources.
Description
Technical field
The present invention relates to multiplex system, relate in particular to a kind of optical wavelength channel protection method and device that is used for dense wavelength division multiplexing system.
Background technology
More common optical wavelength path protection mode has two kinds in the dense wave division multipurpose dwdm system at present: n:m and n+m optical wavelength protected mode.
For the n:m working method; as shown in Figure 1; n backup optical wavelength channel transmits low priority traffice when system's fault-free; but when certain or several optical wavelength passages in m the optical wavelength passage break down; the low priority traffice of backup path is dropped; the business of faulty channel is switched to backup path to be transmitted; n:m optical wavelength path protection mode in fact just shifts faulty channel; really systematic function is not carried out complete error protection; therefore n:m Optical Channel Protection mode seldom is utilized on DWDM backbone network, and this protected mode is used in the circuit stages protection more.
Under n:m optical wavelength path protection mode, n backup wavelength channel also has certain priority, both when certain service aisle breaks down, can the backup path business that priority is minimum abandon, the service signal of simultaneous faults unit is switched to this backup path through the n*m cross matrix and is transmitted, and the priority of this backup path is updated simultaneously; When other has a service aisle to break down; this moment, system can check remaining n-1 backup wavelength channel service priority; determine this with the fault switching services to which back up wavelength channel; system can control n*m and switch matrix after inquiry; the switching services of the faulty channel backup wavelength channel to lowest priority is transmitted; certainly; the former low priority traffice of this wavelength channel can be abandoned; the service priority sign of backup path can be updated simultaneously; so analogize, progressively realize the backup protection of n backup wavelength channel m service aisle business.
For n+m optical wavelength path protection mode; as shown in Figure 2; when operate as normal; m operation wavelength passage bearer service; n backup wavelength channel unit then is in the Hot Spare state; each backup wavelength channel all carries out the Hot Spare protection to a corresponding operation wavelength passage, promptly backs up wavelength channel and the identical business of operation wavelength passage carrying.Because be Hot Spare, so modal n+m protection form is exactly 1+1.When certain protected operation wavelength passage broke down, receiving terminal can compare the quality of service of the backup wavelength channel of operation wavelength passage and correspondence, selected backup wavelength channel loaded service to finish defencive function.If have an operation wavelength passage to break down this moment in addition, then receiving terminal compares to determine whether switch operation wavelength passage loaded service and backup wavelength channel loaded service equally; In like manner so analogize, transmission mission when the backup wavelength channel is born the operation wavelength passage and broken down, but the business of the operation wavelength passage that the backup wavelength channel is equally must carrying corresponding when fault-free, backup wavelength channel are carried the business of which operation wavelength passage and can be specified by configuration n*m matrix.
But no matter be n:m or n+m optical wavelength path protection mode; all required n backup wavelength channel to use as backup; in other words; all be by reserving wavelength channel as backup path; realize backup protection to the operation wavelength passage; like this, just must take the wavelength resource of system, the limited wavelength resource of system is not fully utilized.
Summary of the invention
The object of the present invention is to provide a kind of the optical wavelength channel protection method and the device that are used for dense wavelength division multiplexing system high to the wavelength resource utilance of system.
The technical solution adopted in the present invention is: a kind of optical wavelength channel protection method that is used for dense wavelength division multiplexing system, it is characterized in that: when the operation wavelength passage of described dense wavelength division multiplexing system breaks down, system control unit is closed the transmission and the reception optical conversion unit of this wavelength channel two ends correspondence, and it is malfunction that this corresponding optical conversion unit is set; Select the temporary transient load bearing unit of a backup wavelength-tunable optics converting unit that is ready as faulty channel; The output wavelength that system adjusts this backup wavelength-tunable optics converting unit is the carrier wavelength of faulty channel, the business of faulty channel is switched to backup wavelength-tunable optics converting unit transmit; After switching, the operating state of backup wavelength-tunable optics converting unit is revised by the work of awaiting orders by system.
After the described wavelength channel that breaks down was repaired, system closing backup wavelength-tunable optics converting unit started the optical conversion unit of working channel simultaneously, and service circuit is switched back former operating state.
The transmitting terminal system increases the attached wave multiplexer that adds, and the light signal and the output of described backup wavelength-tunable optics converting unit of the described work optical conversion unit output of transmitting terminal merge through additional wave multiplexer, insert transmission link.
Receiving terminal system can increase the attached channel-splitting filter that adds, and is provided with adjustable filter in the additional channel-splitting filter, and the light signal of described transmission link output enters channel-splitting filter through described additional channel-splitting filter, is linked into the optical conversion unit of respectively working again; When the business with faulty channel switches to backup wavelength-tunable optics converting unit when transmitting, the centre frequency of the adjustable filter of this backup wavelength-tunable optics converting unit correspondence switches to faulty channel centre wavelength outward by the operating frequency band; After faulty channel was repaired, the centre frequency of revising described adjustable filter was to the operating frequency band.
Receiving terminal system also can increase light of company and switch matrix, replaces above-mentioned additional channel-splitting filter, and the light signal of described transmission link output is linked into the optical conversion unit of respectively working again through channel-splitting filter.
The present invention also proposes a kind of optical wavelength path protection device that is used for dense wavelength division multiplexing system, comprise transmitting terminal wave multiplexer and receiving terminal channel-splitting filter, described transmitting terminal and receiving terminal respectively are provided with a plurality of optical conversion units, and respectively connect a light that is used for line switching at the outlet side of the work optical conversion unit of the input side of the work optical conversion unit of transmitting terminal and receiving terminal and switch matrix, it is characterized in that: also comprise additional wave multiplexer, described transmitting terminal wave multiplexer connects additional wave multiplexer; A plurality of backup wavelength-tunable optics converting units are switched matrix with described light and are connected, and the light signal of the light signal of described wave multiplexer output and the output of described backup wavelength-tunable optics converting unit merges through additional wave multiplexer, is linked into transmission link; The light signal of described transmission link enters into optical conversion unit through the receiving terminal channel-splitting filter, and a plurality of backup wavelength-tunable optics converting units are switched matrix with described light and are connected.
Described channel-splitting filter can correspondingly increase the attached channel-splitting filter that adds, and is provided with adjustable filter in the additional channel-splitting filter, and the light signal of described transmission link output enters channel-splitting filter through additional channel-splitting filter, is linked into the optical conversion unit of respectively working again.
Described channel-splitting filter also can correspondingly increase company's light and switch matrix, replaces above-mentioned additional channel-splitting filter, and the light signal of described transmission link output is linked into the optical conversion unit of respectively working again through channel-splitting filter.
Beneficial effect of the present invention is: in the present invention; by increasing the attached wave multiplexer that adds; utilize wavelength-tunable optics converting unit as system optical wavelength passage backup protection unit; reach the purpose that the wavelength channel backup protection does not take system's optical wavelength resources; make that the wavelength practical efficiency of system is 100%, but therefore the system backup performance do not reduce, therefore; the present invention has utilized the limited wavelength resource of system more fully to the wavelength resource utilance height of system.
Description of drawings
Fig. 1 is a n:m Optical Channel Protection mode structural representation in the prior art;
Fig. 2 is a n+m Optical Channel Protection mode structural representation in the prior art;
Fig. 3 is embodiment 1 structural representation;
Fig. 4 is embodiment 2 structural representations.
Embodiment
With embodiment the present invention is described in further detail with reference to the accompanying drawings below:
Embodiment 1:
According to Fig. 3; the present invention includes the wave multiplexer (MUX) of transmitting terminal system and the channel-splitting filter (DEMUX) of receiving terminal system; described transmitting terminal and receiving terminal respectively are provided with a plurality of optical conversion units (OTU) as work OTU; this OTU is a fixed wave length; and each k* (m+n) who is used for line switching of transmitting terminal and receiving terminal switches matrix; wave multiplexer MUX connects additional wave multiplexer; additional wave multiplexer can be that this class of coupler is to the insensitive composite wave appts of wavelength; additional wave multiplexer is connected the wavelength-tunable optics converting unit OTU as system optical wavelength passage backup protection unit with corresponding wave multiplexer MUX; has the wavelength-tunable sending module among the backup optical conversion unit OTU of input; can set up the wavelength-tunable filter plate in the additional wave multiplexer, as acousto-optic tunable filter; electric light tunable optic filter etc.The light signal of the MUX of transmitting terminal system output and backup wavelength-tunable optics converting unit OTU output merge output through additional wave multiplexer, insert transmission link.Receiving terminal increases a k* (m+n) and switches matrix, and this k* (m+n) switches matrix and is connected with DEMUX and backup OTU unit, and the light signal of transmission link output is linked into the OTU unit of respectively working again through DEMUX.
As shown in Figure 3; in normal working conditions; system's original n+m channel is used to working channel fully; be shown as n+m channel herein and then be aimed at the channel of Fig. 1 and Fig. 2, k the backup optical conversion unit OTU as the backup protection unit is ready, and the backup optical conversion unit OTU of transmitting terminal does not have any output; light signal is after being transferred to receiving terminal; by channel-splitting filter DEMUX, enter the optical conversion unit OTU that respectively works, finish reception.
When the operation wavelength passage of dense wavelength division multiplexing system breaks down:
A, system control unit are closed the transmission and the reception optical conversion unit OTU of this wavelength channel two ends correspondence, and it is that fault is to be repaired that this optical conversion unit OTU state is set;
The operating state of B, inquiry transmitting terminal backup optical conversion unit OTU, first is queried to the backup optical conversion unit OTU that the is ready temporary transient load bearing unit as faulty channel;
After C, inquiry are finished, send instructions under the system to this backup optical conversion unit OTU, adjust the carrier wavelength that its output wavelength is a faulty channel, send instructions down and switch matrix to three k* (m+n) and the business of faulty channel is switched to backup optical conversion unit OTU switch transmission, finish backup optical conversion unit OTU unit carrying faulty channel operation flow;
D, switch after, the operating state of backup optical conversion unit OTU is revised by the work of awaiting orders by system.
There is a service aisle also to break down this moment as other, then system control unit is closed the optical conversion unit OTU of this faulty channel in transmitting terminal and receiving terminal correspondence equally earlier, and inquire about first backup optical conversion unit OTU that is ready, finish the transmission of switching of faulty channel business by this process similar to the above.
After the wavelength channel that breaks down is repaired, state by system control unit timing testing passage optical conversion unit OTU, be in standby condition in case find the optical conversion unit OTU of former wavelength channel, system closing backup optical conversion unit OTU, start the optical conversion unit OTU of working channel simultaneously, circuit is switched back former operating state, and each optical conversion unit OTU state is restored to initial condition simultaneously.
Embodiment 2:
According to Fig. 4; the present invention includes the wave multiplexer MUX of transmitting terminal and the channel-splitting filter DEMUX of receiving terminal; described transmitting terminal and receiving terminal respectively are provided with a plurality of optical conversion unit OTU as work OTU; this OTU is a fixed wave length; and transmitting terminal and each matrix of switching that is used for line switching of receiving terminal; transmitting terminal MUX connects additional wave multiplexer; additional wave multiplexer can be that this class of coupler is to the insensitive composite wave appts of wavelength; the corresponding connection of receiving terminal DEMUX adds channel-splitting filter; additional wave multiplexer is connected corresponding wavelength-tunable optics converting unit OTU as system optical wavelength passage backup protection unit respectively with additional channel-splitting filter; have the wavelength-tunable sending module among the wavelength-tunable optics converting unit OTU of input, be provided with the wavelength-tunable filter plate in the additional channel-splitting filter.Can set up the wavelength-tunable filter plate in the additional wave multiplexer, as acousto-optic tunable filter, electric light tunable optic filter, coupler etc.
The light signal of transmitting terminal MUX output and backup wavelength-tunable optics converting unit OTU output merge output through additional wave multiplexer; insert transmission link; enter channel-splitting filter at receiving terminal through additional channel-splitting filter; as system optical wavelength passage backup protection unit, the wavelength-tunable filter plate in the additional channel-splitting filter dissociates out with the backup wavelength channel of correspondence when the operation wavelength passage breaks down with wavelength-tunable optics converting unit OTU.
As shown in Figure 4; in normal working conditions; system's original n+m channel is used to working channel fully; be shown as n+m channel herein and then be aimed at the channel of Fig. 1 and Fig. 2; k the backup optical conversion unit OTU as the backup protection unit is ready; the backup optical conversion unit OTU of transmitting terminal does not have any output; light signal is after being transferred to receiving terminal; system does not carry out any control to additional channel-splitting filter this moment; additional channel-splitting filter does not carry out any processing to light signal this moment yet; light signal directly is transferred to channel-splitting filter DEMUX, enters the optical conversion unit OTU that respectively works at last, finishes reception.
When the operation wavelength passage of dense wavelength division multiplexing system breaks down:
A, system control unit are closed the transmission and the reception optical conversion unit OTU of this wavelength channel two ends correspondence, and it is that fault is to be repaired that this optical conversion unit OTU state is set;
The operating state of B, inquiry transmitting terminal backup optical conversion unit OTU, first is queried to the backup optical conversion unit OTU that the is ready temporary transient load bearing unit as faulty channel;
C, after inquiry is finished, send instructions under the system to this backup optical conversion unit OTU, adjust the carrier wavelength that its output wavelength is a faulty channel, the adjustable filter centre frequency of receiving terminal of backup optical conversion unit OTU correspondence is switched to faulty channel centre wavelength by outside being with, adjust the carrier wavelength that its output wavelength is a faulty channel, switching matrix by corresponding k* (m+n) switches to backup optical conversion unit OTU with the business of faulty channel and switches transmission, the business of faulty channel was all switched to backup optical conversion unit OTU and was transmitted this moment, but the centre carrier frequency of holding this faulty channel business does not on the line change, and has so just finished backup optical conversion unit OTU unit carrying faulty channel operation flow;
D, switch after, the operating state of backup optical conversion unit OTU is revised by the work of awaiting orders by system.
If have other service aisle to continue to break down this moment in addition, then can be as mentioned above, the first closing fault passage of system's meeting, the operating state of the optical conversion unit of inquiry backup simultaneously OTU, select corresponding backup optical conversion unit OTU substituting as faulty channel, send instructions to backup optical conversion unit OTU afterwards down, switch matrix and additional channel-splitting filter, finish corresponding business and switch work, so analogize processing for the fault of follow-up other channel.
After the wavelength channel that breaks down is repaired, state by system control unit timing testing passage optical conversion unit OTU, be in standby condition in case find the optical conversion unit OTU of former wavelength channel, system closing backup optical conversion unit OTU, to add the corresponding adjustable filter centre frequency of channel-splitting filter transfers to outside the working band band, start the optical conversion unit OTU of working channel simultaneously, circuit is switched back former operating state, and each optical conversion unit OTU state is restored to initial condition simultaneously.
In two above embodiment; working channel can be divided into a plurality of channel group in fact; be equipped with the additional wave multiplexer of respective sets number again; backup optical conversion unit OTU in each additional wave multiplexer carries out the optical wavelength path protection to the working channel in the respective channel group; so just formed packet protection to whole service aisle; its principle, structure and control method and front embodiment 1 and embodiment 2 are described basic identical, repeat no more herein.
In the middle of the application of reality, wavelength-tunable optics converting unit OTU connects variable optical attenuator VOA, by using variable optical attenuator VOA to reach the effect of flat gain in this backup optical conversion unit OTU.
Claims (11)
1, a kind of optical wavelength channel protection method that is used for dense wavelength division multiplexing system is characterized in that:
When the operation wavelength passage of described dense wavelength division multiplexing system breaks down:
A, system control unit are closed the transmission and the reception optical conversion unit of this wavelength channel transmitting terminal and receiving terminal correspondence, and it is malfunction that this corresponding optical conversion unit is set;
B, select the temporary transient load bearing unit of a backup wavelength-tunable optics converting unit that is ready as faulty channel;
The output wavelength that C, system adjust this backup wavelength-tunable optics converting unit is the carrier wavelength of faulty channel, the business of faulty channel is switched to backup wavelength-tunable optics converting unit transmit;
D, switch after, the operating state of backup wavelength-tunable optics converting unit is revised by the work of awaiting orders by system.
2, the optical wavelength channel protection method that is used for dense wavelength division multiplexing system according to claim 1; it is characterized in that: after the described wavelength channel that breaks down is repaired; system closing backup wavelength-tunable optics converting unit starts the optical conversion unit of working channel simultaneously, and service circuit is switched back former operating state.
3, the optical wavelength channel protection method that is used for dense wavelength division multiplexing system according to claim 1; it is characterized in that: transmitting terminal increases the attached wave multiplexer that adds; the light signal and the output of described backup wavelength-tunable optics converting unit of the described work optical conversion unit output of transmitting terminal merge through additional wave multiplexer, insert transmission link.
4, the optical wavelength channel protection method that is used for dense wavelength division multiplexing system according to claim 3, it is characterized in that: receiving terminal system can increase the attached channel-splitting filter that adds, be provided with adjustable filter in the additional channel-splitting filter, the light signal of described transmission link output enters channel-splitting filter through described additional channel-splitting filter, is linked into the optical conversion unit of respectively working again;
When the business with faulty channel switches to backup wavelength-tunable optics converting unit when transmitting, the centre frequency of the adjustable filter of this backup wavelength-tunable optics converting unit correspondence switches to faulty channel centre wavelength outward by the operating frequency band;
After faulty channel was repaired, the centre frequency of revising described adjustable filter was to the operating frequency band.
5, the optical wavelength channel protection method that is used for dense wavelength division multiplexing system according to claim 3; it is characterized in that: receiving terminal system can increase light of company and switch matrix; the light signal of described transmission link output is linked into the optical conversion unit of respectively working again through channel-splitting filter.
6, the optical wavelength channel protection method that is used for dense wavelength division multiplexing system according to claim 1 and 2; it is characterized in that further comprising: earlier working channel is divided into a plurality of channel group; set up the additional wave multiplexer of respective sets number again in the transmitting terminal system; backup optical conversion unit OTU in each additional wave multiplexer carries out the optical wavelength path protection to the working channel in the respective channel group, forms the packet protection to whole service aisle.
7, a kind of optical wavelength path protection device that is used for dense wavelength division multiplexing system of realizing claim 1, comprise transmitting terminal wave multiplexer and receiving terminal channel-splitting filter, described transmitting terminal and receiving terminal respectively are provided with a plurality of optical conversion units, and respectively connect a light that is used for line switching at the outlet side of the work optical conversion unit of the input side of the work optical conversion unit of transmitting terminal and receiving terminal and switch matrix, it is characterized in that: also comprise additional wave multiplexer, described transmitting terminal wave multiplexer connects additional wave multiplexer; A plurality of backup wavelength-tunable optics converting units are switched matrix with described light and are connected, and the light signal of the light signal of described wave multiplexer output and the output of described backup wavelength-tunable optics converting unit merges through additional wave multiplexer, is linked into transmission link; The light signal of described transmission link enters into optical conversion unit through the receiving terminal channel-splitting filter, and a plurality of backup wavelength-tunable optics converting units are switched matrix with described light and are connected.
8, the optical wavelength path protection device that is used for dense wavelength division multiplexing system according to claim 7; it is characterized in that: described channel-splitting filter can correspondingly increase the attached channel-splitting filter that adds; be provided with adjustable filter in the additional channel-splitting filter; the light signal of described transmission link output enters channel-splitting filter through additional channel-splitting filter, is linked into the optical conversion unit of respectively working again.
9, the optical wavelength path protection device that is used for dense wavelength division multiplexing system according to claim 7; it is characterized in that: described channel-splitting filter can correspondingly increase company's light and switch matrix; the light signal of described transmission link output is linked into the optical conversion unit of respectively working again through channel-splitting filter.
10, according to claim 7, the 8 or 9 described optical wavelength path protection devices that are used for dense wavelength division multiplexing system, it is characterized in that: in the described additional wave multiplexer adjustable filter can be set.
11, according to claim 7, the 8 or 9 described optical wavelength path protection devices that are used for dense wavelength division multiplexing system, it is characterized in that: described additional wave multiplexer can be a coupler.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02144172 CN1254035C (en) | 2002-10-15 | 2002-10-15 | Light wavelength channel protecting method and apparatus for compact WDM system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02144172 CN1254035C (en) | 2002-10-15 | 2002-10-15 | Light wavelength channel protecting method and apparatus for compact WDM system |
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| Publication Number | Publication Date |
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| CN1490968A CN1490968A (en) | 2004-04-21 |
| CN1254035C true CN1254035C (en) | 2006-04-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 02144172 Expired - Fee Related CN1254035C (en) | 2002-10-15 | 2002-10-15 | Light wavelength channel protecting method and apparatus for compact WDM system |
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100403660C (en) * | 2004-09-04 | 2008-07-16 | 华为技术有限公司 | Dual-fiber optical multiplexing section sharing protective ring protecting method and its node device |
| CN1859062B (en) * | 2006-03-27 | 2011-05-18 | 华为技术有限公司 | Protective method for sharing wave length conversion unit, realizing device and application system |
| CN100488071C (en) | 2006-10-27 | 2009-05-13 | 华为技术有限公司 | Method for protecting photoelectric integrated device and photoelectric integrated device |
| WO2009026853A1 (en) * | 2007-08-25 | 2009-03-05 | Huawei Technologies Co., Ltd. | Method, device and system for setting and maintaining wavelength path |
| CN101374107B (en) * | 2007-08-25 | 2011-03-30 | 华为技术有限公司 | Method, equipment and system for establishing and maintaining wavelength path |
| JP2015522992A (en) * | 2012-05-23 | 2015-08-06 | ▲ホア▼▲ウェイ▼技術有限公司 | Method, system, and apparatus for wavelength switching over a multi-wavelength passive optical network |
| WO2014172828A1 (en) * | 2013-04-22 | 2014-10-30 | 华为技术有限公司 | Method and apparatus for multicarrier spectrum transition in service hitless mode |
| CN111082890B (en) * | 2019-11-11 | 2021-07-27 | 国家电网有限公司 | OLP channel protection switching method based on OTN redundant wave |
| CN114285518B (en) * | 2020-09-28 | 2023-07-18 | 华为技术有限公司 | Optical communication system and connection relationship determination method |
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2002
- 2002-10-15 CN CN 02144172 patent/CN1254035C/en not_active Expired - Fee Related
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