CN100536369C - Service protection device in optical communication network and method thereof - Google Patents
Service protection device in optical communication network and method thereof Download PDFInfo
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Abstract
The invention relates to a business protection technology in the communication system. Especially, the invention discloses an apparatus and method for the business protection in the optical communication network to protect all the business in the network, especially the metro network basing on the photo transmission. The said business protection apparatus and method in the optical communication network apply the null separation cross connection technology to protect businesses. Every node gets the network status by monitoring the node business signal applies the convergence and inverse convergence processing on the user's signal; having cross connection on the business signals according to the network accident conditions and the specified protection mechanism that can be set as channel protection or multiplying phase protection according to the actual need to realize the business protection.
Description
Technical field
Service protection technology in the present invention relates to communicate by letter, the particularly resist technology of business-level in the optical communication network.
Background technology
Along with the progress of science and technology and the development of society, the communication technology becomes more and more important in social production and people's life.In order to adapt to multiple demand, the various communication technologys and communication network are born thereupon.Simultaneously, Ye Wu variation makes communication network need realize the transmission of multi-service efficiently.In recent years, appearance along with emerging services such as broadband access the Internet, mobile communication, Digital Television, multi-media communication, storage, data carried by data business demand sharp increase in the communication network, especially in just the speed sustainable development of big or middle city data business volume to be doubled in each season, and the impetus is also very powerful, this is just to communication network, especially aspects such as the efficiency of transmission of metropolitan area network (Metropolitan Area Networks is called for short " MAN ") and resource utilization have proposed new requirement.The consensus of communication in the circle be, to compare with the digital network of today to be huge to data quantity transmitted in the future network, and require advanced person's regular maintenance and administrative skill.
Be the bridge between structure backbone network and Access Network, and satisfy the demand that develops with intercity business especially data service in the city, metropolitan area network will become the focus that next round telecommunications is built.The metropolitan area network complex environment proposes all difficult problems to the construction of network, thereby produces the new technology of many construction metropolitan area networks.At present, emerging metropolitan area network technology platform: based on SDH (Synchronous Digital Hierarchy) (Synchronous Digital Hierarchy, abbreviation " SDH ") Synchronous Optical Network (Synchronous Optical Network, be called for short " SONET "), Resilient Packet Ring (Resilient Packet Ring, be called for short " RPR "), multi protocol label exchange (Multi-Protocol Label Switching, be called for short " MPLS "), metropolitan area wavelength division multiplexing (WavelengthDivision Multiplexing, be called for short " WDM ") etc., in time alleviated certain transmission pressure, but the existing technical problem of corresponding solution also produces thereupon: bandwidth is not enough, dilatation cost height, the networking complexity, the whole network lacks unified management dispatching etc., has had a strong impact on further developing of communication networks such as metropolitan area network.
At client layer diversity of operations and complexity, the metropolitan area network technology must be to the evolution of efficient carrying multi-service direction.After in backbone network and long-distance network, using, wavelength-division multiplex technique, dense wave division multipurpose (Dense Wavelength Division Multiplexing particularly, be called for short " DWDM ") also begin to use at metropolitan area network, particularly the autgmentability of its huge capacity, network and professional expandability demonstrate distinctive advantage in metropolitan area network.It can provide high bandwidth and support wavelength to hire out, product platform is to protocol transparent, support Internet protocol (Internet Protocol, abbreviation " IP "), time division multiplexing (TimeDivision Multiplexing, be called for short " TDM ") wait multiple business, and can dilatation not influence existing business by opening next wavelength.
The DWDM platform will carry a large amount of all kinds of business for the business transmission provides huge bandwidth resources on this platform.Because dwdm system mainly is positioned at the backbone and the core layer of transmission network, the traffic carrying capacity of the network carrying is very big, therefore, the fault of individual node or the inefficacy of single link all will influence professional quite on a large scale, especially in ring network structure, the fault at arbitrary place all will cause the decline of the whole network efficient in the link, even cause the whole network paralysis.This under the situation that highly depends on information network, allows to occur in current society anything but.Therefore just the reliability of network has been proposed very high requirement, contemporary communication network must be when transmission link or node break down, and service signal is switched to fast protect route to transmit.In the wdm system, the main survivability mechanism that adopts is multiple services service protection scheme and multichannel service protection scheme, is used to improve the reliability of network at present.
Multiple services service protection scheme system block diagram as shown in Figure 1.
In multiple services service protection scheme, each node all comprises a working cell and a protected location, is used for sending and receiving two parts of identical services signals, and service signal is handled.When sending node sends business each business is all duplicated portion, send in network by working cell and protected location simultaneously.Notice that the identical route of business in network of two parts of contents is often different, therefore can receive the service signal that signal quality is different at receiving node.Receiving node is according to the identical services signal that transmits in the signal quality selective reception heterogeneous networks route.In Fig. 1, there are two service signals between node A and the Node B.On the WDM circuit, realize the aggregate transmission of client's business with optical transmission unit (Optical Transmission Unit is called for short " OTU ").Each node all comprises a work OTU and a protection OTU.When node A need send service signal to Node B; at transmitting terminal two service signals are copied into two parts respectively; give work OTU and protection OTU; after Business Processing, service convergence; produce the WDM line signal; give the work OTU and the protection OTU of receiving terminal simultaneously, restore two client signals respectively, receiving terminal selects receipts according to two signal qualitys that receive.Like this, when having portion to break down in two parts of identical service signals, can realize the service protection function by receiving another part.
Multichannel service protection scheme system block diagram as shown in Figure 2.
In multichannel service protection scheme, between node-to-node, also there is the protection passage except service aisle.Service signal sends in two passes simultaneously, selects receipts at receiving terminal.In Fig. 2, two nodes of WDM network only comprise an OTU.After transmitting terminal converges two service signals, send at working channel and protection channel according to 50: 50 power.Select receipts in receiving end according to the signal quality in two channels, and separate and pool two service signals.Like this, in two channels, when having one to break down, the situation of loss of traffic can not occur, realize the service protection function.
As seen; in the above-mentioned existing wdm system at two kinds of protection schemes commonly used of service signal; all be by business or optical passage signal are adopted fixing dual transmitting and receiving device; need be for protected business provide an additional networks transmission quantity or service channel, generally bandwidth availability ratio has only 50%.In the configuration of some complex topology network configuration, bandwidth availability ratio can be lower, for example the distributed service type.Because these two kinds of protected modes all are fixing protected mode, lack flexibility, mainly are applicable to the protection of point to point network, can not satisfy the service protection requirement of the more ring network of current metropolitan area network or other configurations.In fact,, make all channel service amounts of the whole network double, seriously reduced network transmission efficiency because these two kinds of protected modes have all adopted service protection end to end for each business.In addition; because in these two kinds of protected modes; the work route is transmitted along different optical channels with the protection route; in long-distance networking; if work route and protection routed path length exist than big-difference, just must overcome because transmission range increases and the optical property deterioration of introducing is transmitted in multi-service, serious etc. such as optical power attenuation, signal to noise ratio reduction, chromatic dispersion; so and the extra expensive compensating device of introducing will improve network cost and system complexity greatly.
In fact, the underlying cause is that above-mentioned two kinds of schemes do not have the service protection function in the network-wide basis, and different business can only send in wavelength channel separately, and all protection mechanisms must be carried out at business end to end.So just caused, under the various situation of network configuration complexity, class of business, reduced system effectiveness greatly, worsened the service protection performance.
In actual applications, there is following problem in such scheme: professional end to end pilosity makes network resource utilizations such as bandwidth have only 50% at most, the serious waste Internet resources; Protected location that increases or protection passage make system complexity too high; Because the extra compensating device that channel difference is brought has improved network cost; Under and the situation that class of business is various complicated, the service protection function can not be realized efficiently, the demand of current communication network development can not be applicable in network configuration.
Cause the main cause of this situation to be; current multi-service or multichannel service protecting method; all be the fixed service protection mechanism at the end-to-end communication pattern, different business can only transmit in different network channels, and the service protection at business can not be provided in network-wide basis.
Summary of the invention
In view of this; main purpose of the present invention is to provide the devices and methods therefor of the service protection in a kind of optical communication network; make various communication networks; particularly based on the metropolitan area network of optical transmission; realize the service protection in the network-wide basis; can protect the business of variety classes, different port neatly, thereby improve bandwidth availability ratio, improve network reliability and multiple service supporting ability.
For achieving the above object, the invention provides the service protection device in a kind of optical communication network, comprise service protection unit, control unit, a plurality of professional pretreatment unit and professional post-processing unit, wherein,
Described professional pretreatment unit is used for service signal is monitored, and gives described control unit with the state information report that monitors, and will be decomposed into a plurality of separate traffic from the described service signal in line side by pretreatment operation simultaneously;
Described control unit is judged network signal transmission situation according to described state information, according to predefined service protection mechanism decision business safeguard measure, and issues corresponding control information to described service protection unit;
Described service protection unit carries out the interconnection operation according to described control information to described separate traffic, realizes described service protection measure on business-level;
Described professional post-processing unit is used for the described service signal through described interconnection operation is converted to by post-processing operation can be for the signal of output.
Wherein, described separate traffic is the gigabit Ethernet business.
Described preliminary treatment comprises opto-electronic conversion and professional a kind of or its combination of separating in converging, and described reprocessing comprises a kind of or its combination in service convergence and the electric light conversion.
Described service protection mechanism is path protection mechanism;
Described control unit in the sender node of described communication network also is used for when the described service signal of this node is up, controls described service protection unit and carries out described interconnection operation, sends at a plurality of passages;
Described control unit in the receiving terminal node of described communication network also is used for according to described state information, controls described service protection unit and carries out described interconnection operation, the described service signal that selective reception is sent from a plurality of passages.
Described service protection mechanism is multiplex section protection mechanism;
Described control unit also is used for judging according to described state information whether the link adjacent with this node breaks down; If any adjacent link breaks down, then control described service protection unit and carry out described interconnection operation, with the described service signal that originally sent, be transformed into other adjacent link and send in the described adjacent link that breaks down.
Described service protection unit adopts electricity intersection device to realize;
Described service protection unit also is used to receive the signal of telecommunication from the described professional pretreatment unit of client's side, finishes service protection by the interconnection operation, outputs to the described professional post-processing unit in line side; Also be used to receive the signal of telecommunication from the described professional pretreatment unit in line side, finish service protection by the interconnection operation, the signal of telecommunication of the business that need terminate in this locality outputs to the described professional post-processing unit of client's side, and the signal of telecommunication that other are professional outputs to the described professional post-processing unit in line side;
The described professional pretreatment unit of client's side also is used to receive the light signal from the business of client's side, carries out opto-electronic conversion;
The described professional post-processing unit of client's side also is used for the signal of telecommunication from described service protection unit is carried out the electric light conversion, and exports to client's side;
The described professional pretreatment unit in line side also is used to receive the light signal from the business in line side, carries out opto-electronic conversion and business and separates and converge;
The described professional post-processing unit in line side also is used for the signal of telecommunication from described service protection unit is carried out service convergence and electric light conversion, and exports to the line side.
When described service protection unit adopts electricity to intersect the device realization, can adopt the signal transmission between intranodal different units of backboard cabling or cable ways of connecting realization.
Described service protection unit adopts light intersection device to realize;
The described professional pretreatment unit in line side also is used to receive the light signal from the business in line side, carries out opto-electronic conversion and business and separates convergence processing;
The described professional post-processing unit of client's side also is used to receive the signal of telecommunication from the described professional pretreatment unit in line side, carries out the electric light conversion;
Described service protection unit also is used to receive the light signal from the described professional post-processing unit of client's side, finish service protection by the interconnection operation, the light signal of the business that need terminate in this locality outputs to client's side, and other professional light signals output to the described professional pretreatment unit of client's side; Described service protection unit also is used to receive the light signal from client's side, finishes service protection by the interconnection operation, outputs to the described professional pretreatment unit of client's side;
The described professional pretreatment unit of client's side is used for that also the light signal from described service protection unit is carried out opto-electronic conversion to be handled;
The described professional post-processing unit in line side also is used to receive the signal of telecommunication from the described professional pretreatment unit of client's side, carries out outputing to the line side after service convergence processing and the electric light conversion.
When described service protection unit adopts light to intersect the device realization, can adopt optical cable to realize that the signal between the different units of an intranodal transmits.
Described service protection device is applied to the communication network under the distributed service pattern;
Communication network under the described distributed service pattern comprises the sub rate multiplexing system.
Carry out the communication of service protection signaling between the service protection device in the described communication network in each communication node, realize that network state information is shared, finish the service protection cooperation.
Described service signal from the line side is converged by 4 gigabit Ethernets and forms.
The present invention also provides the service protecting method in a kind of optical communication network, comprises following steps:
The professional pretreatment unit of A is monitored the service signal of input, and uploaded state information is given control unit, carries out opto-electronic conversion and business simultaneously and separates and converge;
The B control unit is judged network signal transmission situation according to described state information, according to predefined service protection mechanism, and the decision business safeguard measure, control service protection unit carries out the interconnection operation to described service signal, realizes the service protection function;
The professional post-processing unit of C carries out service convergence and electric light conversion back output to the service signal through described interconnection operation.
Wherein, described service signal is gigabit Ethernet service signal or the service signal that formed by multichannel gigabit Ethernet service convergence.
When described service protection mechanism was path protection mechanism, described step B also comprised following substep:
At transmitting terminal, through described interconnection operation, described service signal is sent at a plurality of passages, at receiving terminal, through described interconnection operation, the described service signal that selective reception is sent from a plurality of passages;
When described service protection mechanism was multiplex section protection mechanism, described step B also comprised following substep:
When monitoring any adjacent link when breaking down,,, be transformed into other adjacent link and sent the described service signal that originally sent in the described adjacent link that breaks down through described interconnection operation.
By relatively finding; technical scheme difference with the prior art of the present invention is; adopted the space division cross interconnection technique to realize the service protection of business-level; each node all passes through the monitoring to the service signal of this node of process; know the network work situation; and client signal converged the reconciliation convergence processing; according to the service protection mechanism of network failure situation and setting service signal is carried out the interconnection operation simultaneously; realize service protection, service protection mechanism can be set at path protection or multiplex section protection etc. according to actual needs.
Difference on this technical scheme, brought comparatively significantly beneficial effect, be that the service protection of business-level makes that each node can both carry out flexibly multiple business in the network, service protection is handled efficiently, Internet resources have been saved greatly, improved resource utilization, save extra compensating device, reduce network cost; System can be set at different service protection mechanism flexibly, improves network reliability; Signaling communication between the network node makes network state information share and the service protection cooperation becomes possibility, has improved the service protection performance, and huge performance extending space is provided.
Description of drawings
Fig. 1 is traditional multiple services service protection scheme system configuration schematic diagram;
Fig. 2 is traditional multichannel service protection scheme system configuration schematic diagram;
Fig. 3 is the service protection apparatus structure schematic diagram that adopts electricity intersection device to realize space division cross according to an embodiment of the invention;
Fig. 4 is the network configuration and the signal flow diagram of service protection device under the employing path protection mechanism according to an embodiment of the invention;
Fig. 5 is network configuration, fault treating procedure and the signal flow diagram of service protection device under the employing multiplex section protection mechanism according to an embodiment of the invention;
Fig. 6 is the Resource Allocation in Networks situation contrast schematic diagram that adopts in the distributed service mode network according to an embodiment of the invention under the different business protective device;
Fig. 7 is the service protection apparatus structure schematic diagram that employing light intersection device according to an embodiment of the invention is realized space division cross;
Fig. 8 is a service protecting method flow chart according to an embodiment of the invention.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with accompanying drawing.
The present invention has provided a kind of service protection apparatus and method based on the space division cross interconnection technique.By intra-node converge, separate the operation of convergence processing and space division cross, make the different business signal in same channels, to transmit, can improve network resource utilization.Simultaneously, the protection mechanism of service channel two ends intranodal combines with interconnection mechanism, has realized the flexible service protection at business in the network-wide basis, improves the reliability of communication network greatly.
In one embodiment of the invention, at WDM, DWDM ring network, employing electricity intersection device has been realized the service protection device based on the space division cross interconnection technique.
Fig. 3 shows the structure based on the service protection device of space division cross interconnection technique that adopts that electricity intersects that device realizes.According to signal flow to, be respectively professional pretreatment unit 301, service protection unit 303, professional post-processing unit 302, and three unit of control unit 304 and other are connected.Wherein being directed to two-way signaling handles, in client's side and line side professional pretreatment unit 301 and professional post-processing unit 302 are arranged all, simple among the figure in order to represent, the professional pretreatment unit 301 and the professional post-processing unit 302 of the same side are drawn in together, and in the practical application, often also two unit are bundled.This space division cross jockey links to each other with a plurality of client signals in client's side, and is continuous at a plurality of optical transmission units (Optical Transmission Unit is called for short " OTU ") of line side and optical transport network.Like this, client's uplink and downlink signals is all handled through the space division cross device, promptly a plurality of service signals can be incorporated in a wavelength and send, also can realize from the network signal of this node of process, decompositing service signal and other service signals of transparent transmission that arrive this node.
At each intra-node,, after professional pretreatment unit 301 opto-electronic conversion of single client side signal through client's side, become the signal of telecommunication and export to service protection unit 303 when when client's side is up to the line side; Professional pretreatment unit 301 is monitored client's side business signal simultaneously simultaneously, produces state information 305 and gives control unit 304; Control unit 304 is according to the state information 305 that receives, and given service protection mechanism, produces corresponding control information 306 and is handed down to service protection unit 303; Client's side business signal that service protection unit 303 is received according to 306 pairs of control informations that receive carries out the interconnection operation; can export to the professional post-processing unit 302 in a plurality of different line sides; produce a plurality of line signals and give corresponding OUT; many channel transfer, reach the service protection purpose.
Same, from the network signal of the input in line side professional pretreatment unit 301 through the line side, separate and pool a plurality of service signals, simultaneously service signal is monitored, produce state information 305 and give control unit 304, control unit 304 is according to the state information 305 that receives, determine service signal in this node termination, and judgement signal quality and network channel failure condition, according to given service protection mechanism, make the service protection decision-making, produce corresponding control information 306 and be handed down to service protection unit 303; The 303 pairs of service signals in service protection unit carry out the interconnection operation, export to the professional post-processing unit 302 of client's side or the professional post-processing unit 302 in line side and carry out subsequent operation, realize the service protection function.
As seen, the service signal between the difference end in the network can penetrate at arbitrary node, in conjunction with the service protection mechanism in the control unit, can realize the interior function of service protection flexibly at business of network-wide basis.And; because the space division cross interconnection technique makes that the service signal between the different nodes in the network can flexible dispatching; realize the channel sharing of different business signal; such as; two business that destination node is different; in the optical-fiber network under the current operation protective device; must be by different wavelength channel transmission; descending at node separately; and under service protection device of the present invention; the business that destination node is different can converge in the transmission of wavelength channel, can both separate in destination node separately and converge and descending, and not disturb mutually.So promptly can save Internet resources, improve network resource utilization, and can avoid the situation of signal power decline in the long-distance networking, save the network cost that the power back-off device brings.
In the above-mentioned service protection device based on the space division cross interconnection technique; each node can freely be provided with service protection mechanism; finish the business information collection by professional pretreatment unit 301; the service protection that carries out by control unit 304 is made a strategic decision; and finish service protection by the interconnection operation of cross unit 303 and operate, at last by up, the descending or transparent transmission of professional post-processing unit 302 service signals.
According to the heterogeneous networks demand different service protection mechanism is set, can realizes the multiple business protection.Such as under path protection mechanism, sending node sends to a plurality of OTU outlets with up single service signal when interconnection is operated, arrive destination node through a plurality of channel transfer; And destination node is when receiving, the quality of the service signal of coming according to different channel transfers, the selective reception quality is passage preferably, and the transmitting-receiving two-end node can intercom mutually adjust the protection passway by with the service aisle route.Again such as under multiplex section protection mechanism; node transmits situation according to the Network signal; detect the signal intelligence of each section link in the network; when certain section continuous link breaks down in detecting looped network; finish the protection switching operation by the interconnection operation; service signal on the former fault link is switched on other normal link transmits, finish the service protection function.
In one embodiment of the invention, adopt path protection mechanism to realize the service protection device.If adopt this space division cross function executing path protection; the client signal that client's side is uploaded through the service protection cell processing after; give simultaneously in the looped network along two professional post-processing units that transmit in opposite direction; deliver to destination node through different routes; service protection unit by destination node carries out the interconnection operation according to the control information of control unit to service signal; give the professional post-processing unit of client's side, produce the service signal that client's side needs.
Fig. 4 shows the network configuration and the signal flow diagram of service protection device under the employing path protection mechanism according to an embodiment of the invention.
Form a looped network by 401,402,403,404 4 nodes of node among Fig. 4 a, outer shroud in the counterclockwise direction, interior ring along clockwise direction, when two clients of node 401 communicate by letter with two clients of node 402 respectively.Under path protection mechanism, sending node all transmits service signal in the OTU of both direction, and receiving node is then received two parts of identical service signals.
Among Fig. 4, under the service protection device effect of node 401, control unit control service protection unit converges the back with service signal and sends at two passages 402 two clients' service signal respectively from node 401 to node.In first passage, service signal is sent to node 402 at interior ring through node 403 by OTU 405, and these two service signals are respectively 411,413; When service signal 411,413 arrives node 402, receive by OTU 407, the processing of the service protection device of process node 402, control unit control service protection unit is separated service signal and is sent the corresponding target node to.Same, in second passage, service signal is sent to node 402 at outer shroud through node 401 by OTU 406, and these two service signals are respectively 412,414; When service signal 412,414 arrives node 402, receive by OTU 408, to handle through the service protection device of node 402, control unit control service protection unit comes out to send to the corresponding target node with the service signal sub-argument.Service signal 411,412 is sent to same destination node, and service signal 413,414 is sent to another destination node.
Otherwise, turn back to the same processing of service signal of node 401 from node 402, illustrate among Fig. 4.At first passage, service signal 421,423 sends from OTU 407, arrives nodes 401 through node 403, is decomposed and is sent to corresponding target node client by OTU 405; At second passage, service signal 422,424 sends from OTU 408, and node 404 arrives nodes 401, is decomposed and is sent to the corresponding target node by OTU 406.
With shown in the solid line being service aisle, what be shown in broken lines is the protection passage among Fig. 4.Service protection is handled down like this, and all service signals all send through two passages and arrive the destination separately, reach the function of path protection.When the network operate as normal, each customer selecting received signal quality is service signal preferably.When one of them passage broke down, the service signal in another passage can reach the professional purpose of protection.Such as; when the communication link of node among Fig. 4 403 between node 401 breaks down; the service signal 411,413,421,423 in left side is all lost, and the identical service signal of the content on right side 412,414,422,424 and unaffected, reaches the purpose of service protection.
In a preferred embodiment of the present invention; the service protection device is realized the service protection function according to the line fault situation; under the normal situation about sending of service signal; only send with service aisle; when the state information judgment task passage that reports according to professional pretreatment unit etc. breaks down, then adopt the protection passage to send.Can improve network resource utilization like this, and reach the service protection purpose equally.
In another embodiment of the present invention; adopt multiplex section protection mechanism to realize the service protection device, when network link breaks down, the service protection device of the node adjacent with faulty link; according to detected link failure situation, the service protection that carries out under the multiplex section protection mechanism is handled.To originally be sent to the service signal of faulty link direction, and forwarded other direction to and continue transmission.Control unit control service protection unit carries out service protection to be handled, and the service signal that this section is uploaded all is sent in the link of operate as normal and transmits; And in the service signal that other nodes send, needs are transparent to the service signal separation of faulty link direction and carry out the loopback operation, be switched to the continuous transmission of link trunking of operate as normal.Realize the switch processing of multiplex section protection thus at this node.
Fig. 5 a shows the network configuration and the signal flow diagram of service protection device under the employing multiplex section protection mechanism according to an embodiment of the invention; Fig. 5 b shows the network failure processing procedure and the signal flow diagram of service protection device under the employing multiplex section protection mechanism according to an embodiment of the invention.
In Fig. 5 a, provided the distribution situation of one four node looped network middle part separate service, the service signal 513 from node 501 to 503 directly transmits by OTU; The service signal that turns back to node 501 from node 503 direct transfers by OTU and send; The transparent transmission that 503 service signal 543 needs through node 501 from node 504 to node reaches node 503; Turn back to the transparent transmission that 534 of node 504 also needs process node 501 from node 503, arrive node 504.Notice; under the service protection device of space division cross is handled; service signal 513 and 543 converges in a channel transfer at node 501; service signal 531 and 534 converges in a channel transfer at node 503; and when arriving node 501; decompose and downlink business signal 531 transparent transmission service signal 534.
In Fig. 5 b, when the link between node 501 and the node 503 broke down, faulty link was shown in broken lines.The node 501 that then links to each other with faulty link and the service protection device of node 503 carry out service protection under multiplex section protection mechanism handles.In node 501, the service signal 513 that originally transmits in faulty link sends to other direction, arrives destination node 503 through node 504,502; And the service signal 543 that the node 504 that originally needed transparent transmission is brought in interior environment-development; then the service protection unit under control unit control carries out interlace operation; service signal 543 is carried out the loopback operation, refund node 504, can arrive destination node 503 through node 504,502 at outer shroud.Same, in node 503, then the service signal that returns 531,534 is sent in interior environment-development, through node 502, arrive node 504, decompose service signal at node 504, the service signal 534 of descending node termination, and transparent transmission service signal 531 finally can arrive destination node 501.
As seen, the service protection device of employing space division cross can be realized the multiplex section protection function of client's business realizing the protection of business-level flexibly, the client's business that inserts is had no requirement.And traditional multiplex section protection function can only realize that smallest particles is other protection of wavelength level, and bandwidth availability ratio is very low.
In actual applications; the network application of distributed service pattern usually can occur, above-mentioned service protection device based on the space division cross interconnection technique is when being applied in distributed service pattern following time; its advantage is more remarkable, and bandwidth availability ratio is high more a lot of than traditional protected mode.In one embodiment of the invention, employing space division cross interconnection technique has realized the service protection under the distributed service pattern.
Fig. 6 is the Resource Allocation in Networks situation contrast schematic diagram that adopts in the distributed service mode network according to an embodiment of the invention under the different business protective device.
Fig. 6 a shows in the network model of typical four node distributed service patterns, the Resource Allocation in Networks situation when adopting the traditional business protective device.Node 601,602,603,604 is formed looped networks, all exist between adjacent arbitrarily two nodes in four nodes bandwidth identical client signal connect, promptly need four service aisles altogether, illustrate with solid line among the figure.Under the transport service protective device, need provide a protection passage for each service aisle, therefore increase by four protection passages, be shown in broken lines among the figure.Each passage is as long as transmission just must be adopted different wavelength resources on a link.Therefore, as seen from the figure, in any one section link four different channel transfer are arranged, this has just determined this network to need four wavelength resources just can finish the service protection function at least, and network resource utilization is very low.
Fig. 6 b shows according to an embodiment of the invention in the network model of four identical node distributed service patterns, the Resource Allocation in Networks situation when adopting the service protection device of space division cross.Because space division cross service protection device realized service convergence, separate converge, transparent transmission and the function of interlace operation arbitrarily, make and can use a wavelength channel can finish the aggregate transmission of multiple business passage on any one section link.And when adopting service protection device under the above-mentioned multiplex section protection mechanism, not needing the extra protection passage that adds, the service protection of each node is switched processing can realize the service protection function neatly.Whole protect networks mechanism and working mechanism's one integrated mass are among the figure shown in the dotted line ring.As seen, adopt the space division cross service protection device under the multiplex section protection mechanism, only need a wavelength resource; and reserve the idle bandwidth identical in each passage with service aisle; as the share protect bandwidth, just can protect the line fault between the node, the network resource utilization height.
In one embodiment of the invention; the system of 5G line unit is provided at 4 GE signal transparent mapped that provide in invention " a kind of sub rate multiplexing methods, devices and systems " (number of patent application is: " 200410003052.0 "); adopt the service protection device under the distributed service pattern of the present invention; just can realize the service protection of GE business, save Internet resources greatly.
Simultaneously; adopt the service protection device of space division cross; except can improving network resource utilization; all can carry out signal processing operations because protection is professional at each node; therefore can overcome the inconsistent Signal Degrade that brings of path of traditional active channel and protection path process; can avoid using expensive image intensifer and other compensating devices, reduce network cost greatly.
In a preferred embodiment of the present invention; each node of the whole network is by the service protection signaling of independent framing or by service signal frame loaded service protection signaling; intercom mutually; share the state information and the node resource of the whole network; the protection mechanism of Coordination Treatment the whole network business is finished to high efficient and flexible the service protection function.Simultaneously, node can be set service protection mechanism neatly, by the collaborative work of each unit of above-mentioned service protection mechanism; finish the service protection function; coordinate other nodes simultaneously, finish the service protection function of other node traffics, make the whole network form an entity.
Key technology of the present invention be to use based on space division cross realize flexibly in the client signal rank, service protection function efficiently; after the decomposition of finishing service signal; implementation as for empty separate service protected location can be diversified; realize such as above-mentioned employing electricity interconnection chip; perhaps also can adopt the optical cross connect chip to realize the service protection unit that for example adopts discrete elements such as optical switch, coupler to build.
Fig. 7 shows in one embodiment of the invention, adopts the service protection apparatus and method of optical cross connect chip realization based on the space division cross interconnection technique.When adopting light to intersect device when realizing the space division cross of business-level, the light signal that must be earlier a plurality of service signals in line side be converged is decomposed into the light signal of single business, directly carries out space division cross then and operate between these light signals and client's light signal.So, online drive test must be finished the decomposition of light signal earlier and converge, in this embodiment of the present invention, professional preliminary treatment of employing ground floor earlier or post-processing unit carry out opto-electronic conversion and signal of telecommunication decomposition or converge, the signal of telecommunication after will decomposing or converge then, finish the electric light conversion by professional preliminary treatment of the second layer or post-processing unit, obtain light signal.
In Fig. 7, the service protection device is made up of service protection unit and inside and outside two layer service preliminary treatment, post-processing unit.Client side signal 1～n gives light service protection unit; directly the photosphere client signal is carried out the interconnection operation; client's light signal after output intersects is given the professional post-processing unit of internal layer again; carry out opto-electronic conversion; be transformed to client's signal of telecommunication; a plurality of client's signals of telecommunication with equidirectional converge to outer field single professional post-processing unit then, and the electric light conversion by this business post-processing unit sends on OTU.In like manner; the line-side signal of input is through the electric light conversion process of outer field professional pretreatment unit; be converted to the signal of telecommunication; and be decomposed into a plurality of professional signals of telecommunication; respectively each professional signal of telecommunication is sent separately to a professional pretreatment unit of internal layer then; through the electric light conversion; send light service protection unit to; after the interlace operation; the client signal that needs are descending is passed to respective client; need the interior layer service post-processing unit of then returning to of transparent transmission, converge to outer layer service post-processing unit with above-mentioned up client's signal of telecommunication, and send at OTU through the electric light conversion through after the opto-electronic conversion.
In above-mentioned service protection process; professional preliminary treatment, post-processing unit detect service signal; and uploaded state information gives control unit, and control unit is judged the network link working condition according to the business state information of receiving, and issues corresponding control information to the service protection unit.The service protection unit carries out corresponding interlace operation according to the control information that receives.The optical cross connect operation is similar with electric interconnection method of operation, and different places is that the signal of direct interlace operation is a light signal.In one embodiment of the invention, directly adopt optical fiber to realize that the signal between the different units connects in the optical cross connect operation.
Those of ordinary skill in the art are appreciated that; the space division cross interconnection technique that is adopted in the above-mentioned service protection device; except electricity intersection device and light intersection device; can also adopt other any methods to realize according to system's needs; can finish goal of the invention equally, and not influence the spirit and scope of the invention.
At last, Fig. 8 shows service protecting method flow chart according to an embodiment of the invention.
In step 801, professional pretreatment unit is monitored service signal, and uploaded state information is given control unit, finishes the pretreatment operation to service signal simultaneously.
Then enter step 802, control unit judges that according to the state information that reports the signal of each passage of network transmits situation, according to the service protection mechanism of setting, and the decision business safeguard measure, and issue corresponding control information to the service protection unit.
Then enter step 803, cross-connect module carries out the interconnection operation according to control information to the service signal after the preliminary treatment, realizes the service protection function.Such as, the service signal after the up service signal of pretreated client's side and line side decomposed carries out the interconnection operation, and sends the corresponding service post-processing unit to.And will need descending line side service signal to send client's side business post-processing unit to; Service signal with needing up service signal of client's side needs and line side to need transparent transmission converges to the corresponding service post-processing unit.Under situation about occurring, make corresponding change in fault.
As previously mentioned, under path protection mechanism, transmitting terminal sends up service signal being cross connected to a plurality of unit respectively at many passages, then select receipts according to signal quality at receiving terminal.
Under multiplex section protection; then processing such as transmit, switch according to the network failure situation; when in a single day the service protection device of each node finds that adjacent link breaks down; promptly start the service protection flow process; in the service protection flow process, the service protection unit will mail to the up service signal and the service signal that needs other nodes of transparent transmission of this node of faulty link under normal operation under the control of control unit; be redirected to normal link, with service signal in the protecting network.
Then enter step 804, professional post-processing unit carries out reprocessing to the service signal after intersecting.
Those of ordinary skill in the art are appreciated that; in the above-mentioned service protection device; except described path protection mechanism and multiplex section protection mechanism; can also be according to the real network demand; set other suitable service protection mechanism; realize service protection, also can finish goal of the invention, and not influence the spirit and scope of the invention.
Though by reference some preferred embodiment of the present invention, the present invention is illustrated and describes, but those of ordinary skill in the art should be understood that, can do various changes to it in the form and details, and the spirit and scope of the present invention that do not depart from appended claims and limited.
Claims (15)
1. the service protection device in the optical communication network is characterized in that, comprises service protection unit, control unit, a plurality of professional pretreatment unit and professional post-processing unit, wherein,
Described professional pretreatment unit is used for service signal is monitored, and gives described control unit with the state information report that monitors, and will be decomposed into a plurality of separate traffic from the described service signal in line side by pretreatment operation simultaneously;
Described control unit is judged network signal transmission situation according to described state information, according to predefined service protection mechanism decision business safeguard measure, and issues corresponding control information to described service protection unit;
Described service protection unit carries out the interconnection operation according to described control information to described separate traffic, realizes described service protection measure on business-level;
Described professional post-processing unit is used for the described service signal through described interconnection operation is converted to by post-processing operation can be for the signal of output.
2. the service protection device in the optical communication network according to claim 1 is characterized in that, described separate traffic is the gigabit Ethernet business.
3. the service protection device in the optical communication network according to claim 2; it is characterized in that; described preliminary treatment comprises opto-electronic conversion and professional a kind of or its combination of separating in converging, and described reprocessing comprises a kind of or its combination in service convergence and the electric light conversion.
4. the service protection device in the optical communication network according to claim 3 is characterized in that, described service protection mechanism is path protection mechanism;
Described control unit in the sender node of described optical communication network also is used for when the described service signal of this node is up, controls described service protection unit and carries out described interconnection operation, sends at a plurality of passages;
Described control unit in the receiving terminal node of described optical communication network also is used for according to described state information, controls described service protection unit and carries out described interconnection operation, the described service signal that selective reception is sent from a plurality of passages.
5. the service protection device in the optical communication network according to claim 3 is characterized in that, described service protection mechanism is multiplex section protection mechanism;
Described control unit also is used for judging according to described state information whether the link adjacent with described device breaks down; If any adjacent link breaks down, then control described service protection unit and carry out described interconnection operation, with the described service signal that originally sent, be transformed into other adjacent link and send in the described adjacent link that breaks down.
6. according to the service protection device in any described optical communication network in the claim 1 to 5, it is characterized in that described service protection unit adopts electricity intersection device to realize;
Described service protection unit also is used to receive the signal of telecommunication from the described professional pretreatment unit of client's side, finishes service protection by the interconnection operation, outputs to the described professional post-processing unit in line side; Also be used to receive the signal of telecommunication from the described professional pretreatment unit in line side, finish service protection by the interconnection operation, the signal of telecommunication of the business that need terminate in this locality outputs to the described professional post-processing unit of client's side, and the signal of telecommunication that other are professional outputs to the described professional post-processing unit in line side;
The described professional pretreatment unit of client's side also is used to receive the light signal from the business of client's side, carries out opto-electronic conversion;
The described professional post-processing unit of client's side also is used for the signal of telecommunication from described service protection unit is carried out the electric light conversion, and exports to client's side;
The described professional pretreatment unit in line side also is used to receive the light signal from the business in line side, carries out opto-electronic conversion and business and separates and converge;
The described professional post-processing unit in line side also is used for the signal of telecommunication from described service protection unit is carried out service convergence and electric light conversion, and exports to the line side.
7. the service protection device in the optical communication network according to claim 6; it is characterized in that; when described service protection unit adopts electricity to intersect the device realization, adopt backboard cabling or cable ways of connecting to realize the transmission of the signal between the different units in the described device.
8. according to the service protection device in any described optical communication network in the claim 1 to 5, it is characterized in that described service protection unit adopts light intersection device to realize;
The described professional pretreatment unit in line side also is used to receive the light signal from the business in line side, carries out opto-electronic conversion and business and separates convergence processing;
The described professional post-processing unit of client's side also is used to receive the signal of telecommunication from the described professional pretreatment unit in line side, carries out the electric light conversion;
Described service protection unit also is used to receive the light signal from the described professional post-processing unit of client's side, finish service protection by the interconnection operation, the light signal of the business that need terminate in this locality outputs to client's side, and other professional light signals output to the described professional pretreatment unit of client's side; Described service protection unit also is used to receive the light signal from client's side, finishes service protection by the interconnection operation, outputs to the described professional pretreatment unit of client's side;
The described professional pretreatment unit of client's side is used for that also the light signal from described service protection unit is carried out opto-electronic conversion to be handled;
The described professional post-processing unit in line side also is used to receive the signal of telecommunication from the described professional pretreatment unit of client's side, carries out outputing to the line side after service convergence processing and the electric light conversion.
9. the service protection device in the optical communication network according to claim 8 is characterized in that, when described service protection unit adopts light to intersect the device realization, can adopt optical cable to realize that the signal between the interior different units of described device transmits.
10. the service protection device in the optical communication network according to claim 2 is characterized in that, described service protection device is applied to the communication network under the distributed service pattern;
Communication network under the described distributed service pattern comprises the sub rate multiplexing system.
11. according to the service protection device in any described optical communication network in the claim 1 to 5; it is characterized in that; carry out the communication of service protection signaling between the service protection device in the described optical communication network in each communication node, realize that network state information is shared, finish the service protection cooperation.
12. the service protection device according in any described optical communication network in the claim 1 to 5 is characterized in that, described service signal from the line side is converged by 4 gigabit Ethernets and forms.
13. the service protecting method in the optical communication network is characterized in that, comprises following steps:
The professional pretreatment unit of A is monitored the service signal of input, and uploaded state information is given control unit, carries out opto-electronic conversion and business simultaneously and separates and converge;
The B control unit is judged network signal transmission situation according to described state information, according to predefined service protection mechanism, and the decision business safeguard measure, control service protection unit carries out the interconnection operation to described service signal, realizes the service protection function;
The professional post-processing unit of C carries out service convergence and electric light conversion back output to the service signal through described interconnection operation.
14. the service protecting method in the optical communication network according to claim 13 is characterized in that, described service signal is gigabit Ethernet service signal or the service signal that formed by multichannel gigabit Ethernet service convergence.
15. the service protecting method in the optical communication network according to claim 14 is characterized in that, when described service protection mechanism was path protection mechanism, described step B also comprised following substep:
At transmitting terminal, through described interconnection operation, described service signal is sent at a plurality of passages, at receiving terminal, through described interconnection operation, the described service signal that selective reception is sent from a plurality of passages;
When described service protection mechanism was multiplex section protection mechanism, described step B also comprised following substep:
When monitoring any adjacent link when breaking down,,, be transformed into other adjacent link and sent the described service signal that originally sent in the described adjacent link that breaks down through described interconnection operation.
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| Application Number | Priority Date | Filing Date | Title |
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| CNB2004100370147A CN100536369C (en) | 2004-04-21 | 2004-04-21 | Service protection device in optical communication network and method thereof |
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| CNB2004100370147A CN100536369C (en) | 2004-04-21 | 2004-04-21 | Service protection device in optical communication network and method thereof |
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| CN100536369C true CN100536369C (en) | 2009-09-02 |
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Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN100440800C (en) * | 2005-11-30 | 2008-12-03 | 中兴通讯股份有限公司 | Method for realizing regional-field network WAN port TRUNK protection |
| CN1988470B (en) * | 2005-12-21 | 2011-01-05 | 华为技术有限公司 | Service protecting method and device |
| CN101383754B (en) * | 2007-09-06 | 2012-12-12 | 华为技术有限公司 | Service transmission method, communication system and related equipment |
| CN101978629B (en) * | 2008-02-04 | 2013-08-21 | 中兴通讯股份有限公司 | System and method for implementing an automatic discovery function in a dwdm network |
| CN101345600B (en) * | 2008-08-21 | 2012-05-23 | 中兴通讯股份有限公司 | Method and system for realizing sub-wavelength channel sharing protection in electric cross mode |
| CN101873192B (en) * | 2009-04-21 | 2014-05-21 | 华为技术有限公司 | Method and device for transmitting constant-rate data stream |
| CN101640818B (en) * | 2009-09-08 | 2012-09-05 | 中兴通讯股份有限公司 | Protection device and protection method of optical network |
| CN105991455B (en) | 2015-02-03 | 2019-11-19 | 华为技术有限公司 | A kind of service switching system and service switching method |
| CN104967566B (en) * | 2015-05-06 | 2018-04-13 | 广州供电局有限公司 | Automatically switching optical networks little particle service path method and device for planning |
| CN112218179B (en) * | 2019-07-09 | 2023-05-09 | 中兴通讯股份有限公司 | Service protection method, device and system |
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