CN113873359A

CN113873359A - Optical transport network route calculation method, device and computer readable storage medium

Info

Publication number: CN113873359A
Application number: CN202010622043.9A
Authority: CN
Inventors: 贾殷秋
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2021-12-31

Abstract

The invention discloses a method, equipment and a computer readable storage medium for calculating an OTN (optical transport network) route, wherein the method for calculating the OTN route comprises the steps of obtaining a first service route request; generating a first initial routing path according to the first service routing request; and updating the routing path of the first initial routing path in the network element according to the resource information of the network element through which the first initial routing path passes, so as to obtain a first target routing path. The resource information of the network element is optimized through the first initial routing path, and the complexity of routing calculation inside the network element can be reduced, so that the complexity of routing calculation of the OTN can be reduced, a target routing path can be obtained more quickly, and the calculation efficiency of routing is improved.

Description

Optical transport network route calculation method, device and computer readable storage medium

Technical Field

The present invention relates to, but not limited to, the field of communications technologies, and in particular, to a method and an apparatus for calculating a route of an optical transport network, and a computer-readable storage medium.

Background

An Optical Transport Network (OTN) technology is a novel Optical Transport technology system, inherits the advantages of a Synchronous Digital Hierarchy (SDH) Network and a Wavelength Division Multiplexing (WDM) Network, and has the advantages of large capacity and a good management and control mechanism. The OTN may implement functions of transmission, switching, multiplexing, etc. of signals of various granularities. Meanwhile, the OTN can support various upper layer services and protocols, and is an important networking technology for bearing an optical network.

Due to the development of a flexible grid technology, the transmission bandwidth of an optical transmission layer of the OTN is variable, and the utilization rate of network resources and the intelligent degree of the network are effectively improved. However, due to the introduction of the flexible grid technology, the complexity of the routing calculation of the OTN network is greatly increased, which is specifically embodied as follows: (1) the resource granularity is reduced, and the total resource description amount is increased; (2) the number of routing problem variables is increased, the line side rate, the modulation format and the Forward Error Correction (FEC for short) of signals can be changed, in practical application, the FEC type has little influence on the spectrum width, and the transmission spectrum width can be determined uniquely by the { line side rate, modulation format } binary group, so that the resource constraint of a traffic engineering LINK (TE LINK ) needs to be met; (3) the network is heterogeneous, different network elements and single boards only support part of line side rates, modulation formats and FEC types due to different configurations, and in addition, optical modules of different manufacturers are adopted in equipment, so that even if the triplets are completely consistent, the problem that signals cannot be communicated exists. The above factors all cause the existing routing algorithm facing the fixed grid OTN network, and in the course of solving the routing calculation problem in a flexible grid scene, the gateway device is easily caused to make a wrong judgment on the RSSI of the STA, thereby affecting the use of the network, and the user experience is poor.

Disclosure of Invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

Embodiments of the present invention provide a method and an apparatus for calculating a route of an optical transport network, and a computer-readable storage medium, which can reduce complexity of route calculation and improve efficiency of route calculation.

In a first aspect, an embodiment of the present invention provides a method for calculating an OTN route of an optical transport network, including,

acquiring a first service routing request;

generating a first initial routing path according to the first service routing request;

and updating the routing path of the first initial routing path in the network element according to the resource information of the network element through which the first initial routing path passes, so as to obtain a first target routing path.

In a second aspect, an embodiment of the present invention further provides an apparatus, including: a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the OTN route calculation method of the first aspect as described above when executing the computer program.

In a third aspect, an embodiment of the present invention further provides a computer-readable storage medium, which stores computer-executable instructions, where the computer-executable instructions are configured to execute the OTN routing computation method according to the first aspect.

The embodiment of the invention comprises the following steps: acquiring a first service routing request; generating a first initial routing path according to the first service routing request; and updating the routing path of the first initial routing path in the network element according to the resource information of the network element through which the first initial routing path passes, so as to obtain a first target routing path. According to the scheme provided by the embodiment of the invention, the complexity of the routing calculation inside the network element can be reduced by optimizing the resource information of the network element passed by the first initial routing path, so that the complexity of the routing calculation of the OTN can be reduced, and the calculation efficiency of the routing can be improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

Fig. 1 is a schematic diagram of an OTN network topology for performing an OTN routing calculation method of an optical transport network according to an embodiment of the present invention;

fig. 2 is a schematic diagram of an OTN network topology for performing an OTN routing calculation method of an optical transport network according to another embodiment of the present invention;

fig. 3 is a flowchart of a method for calculating an OTN route of an optical transport network according to an embodiment of the present invention;

fig. 4 is a flowchart of a method for calculating an OTN route of an optical transport network according to another embodiment of the present invention;

fig. 5 is a flowchart of a combination of units in an OTN routing calculation method for an optical transport network according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a combination of units in a network element of an optical transport network OTN provided by an embodiment of the present invention;

fig. 7 is a flowchart of topology pruning in an OTN routing computation method of an optical transport network according to an embodiment of the present invention;

fig. 8 is a flowchart of resource deployment in an OTN routing computation method of an optical transport network according to an embodiment of the present invention;

fig. 9 is a flowchart of target routing path calculation and update in an OTN routing calculation method of an optical transport network according to an embodiment of the present invention;

fig. 10 is a flowchart of resource backtracking in an OTN routing computation method of an optical transport network according to an embodiment of the present invention;

fig. 11 is a schematic diagram of connection link weights between network elements of an optical transport network OTN according to an embodiment of the present invention;

fig. 12 is a schematic connection diagram between virtual units after resource expansion in a network element of an optical transport network OTN according to an embodiment of the present invention;

fig. 13 is a schematic connection diagram between virtual units after resource backtracking in a network element of an optical transport network OTN according to an embodiment of the present invention;

fig. 14 is a schematic connection diagram between virtual units after resource backtracking in a network element of an optical transport network OTN according to another embodiment of the present invention;

fig. 15 is a device of a method for calculating an OTN route of an optical transport network according to another embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It should be noted that although functional blocks are partitioned in a schematic diagram of an apparatus and a logical order is shown in a flowchart, in some cases, the steps shown or described may be performed in a different order than the partitioning of blocks in the apparatus or the order in the flowchart. The terms "first," "second," and the like in the description, in the claims, or in the drawings described above, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

The invention provides a method, equipment and a computer readable storage medium for calculating the route of an optical transport network, wherein the method for calculating the route of the optical transport network comprises the steps of obtaining a first service route request; generating an initial routing path according to the first service routing request; and updating the routing path of the initial routing path in the network element according to the resource information of the network element through which the initial routing path passes, so as to obtain the target routing path. The resource information of the network element is optimized through the initial routing path, so that the complexity of OTN network routing calculation can be reduced, and the routing calculation efficiency is improved.

The embodiments of the present invention will be further explained with reference to the drawings.

As shown in fig. 1, fig. 1 is a schematic diagram of an OTN network topology for performing an OTN route calculation method according to an embodiment of the present invention. The OTN network topology includes a first network element S, a second network element B, a third network element C, a fourth network element D, and a route calculation module (not shown in the figure) for calculating a route path, where the first network element S is connected to the second network element B and the third network element C, the fourth network element D is connected to the second network element B and the third network element C, the route calculation module is connected to the first network element S, the second network element B, the third network element C, and the fourth network element D, and the first network element S, the second network element B, the third network element C, and the fourth network element D are connected by TE links.

It should be noted that the number of network elements included in the OTN network topology may be 4, and may be 5, and the embodiment of the present application is not particularly limited.

It should be noted that, in an Automatic Switched Optical Network (ASON) technology and a Software Defined Network (SDN), a route calculation module for implementing route Path calculation in an OTN Network may be a Path Calculation Element (PCE) module in the ASON and the SDN, and the embodiment of the present invention is not limited solely.

Referring to fig. 2, fig. 2 is a schematic resource connection diagram of an OTN network topology according to an embodiment of the present invention. The first network element S, the third network element C, and the fourth network element D respectively include an Optical power Amplifier board (OBA) and an Optical Pre-Amplifier board (OPA), an Optical switching module, an Optical Multiplexer Unit (OMU), an Optical Demultiplexer Unit (ODU), and a circuit board; the second network element B includes an Optical power Amplifier (OBA) and an Optical Pre-Amplifier (OPA), an Optical switching module, an Optical Multiplexer Unit (OMU), and an Optical Demultiplexer Unit (ODU).

Those skilled in the art can understand that multiple units in the internal resources of the first network element S, the second network element B, the third network element C, and the fourth network element D may be connected according to actual needs, and the unit types may also be increased or decreased according to actual needs.

In an embodiment, the first network element S and the fourth network element D may be respectively configured with a plurality of circuit boards, and all the circuit boards may support uplink and downlink transmission requirements of a service; the second network element B can be used as a straight-through passing site without being configured with a circuit board; the third network element C may configure at least two circuit boards, and may configure the circuit boards into 2 types of circuit boards, and the circuit boards may be used as service relays. It should be noted that the number of the circuit boards in each network element may be 2, or 3, and this embodiment is not limited in particular.

In an embodiment, the circuit board may have a plurality of configurations and connection manners, and this embodiment is not particularly limited. For example, the circuit board C11 and the circuit board C12 can be fixedly connected with the client side to realize the relay function of signals; for example, the circuit board C21, the circuit board C22, the circuit board C23 and the circuit board C24 may be connected to different ODU/OMU through intersubframe intersection, and a pair of circuit boards forms a bidirectional optical signal relay in a two-by-two combination manner.

It should be noted that the service information of the first service may include a source network element and a target network element, and this embodiment is not limited uniquely. For example, the information of the source network element and the target network element is specified in the service information of the first service, and the service needs to be transmitted uplink and downlink, which can be realized by the circuit board specified by the service information.

Notably, the resource information for the TE link may include usage status information of the spectrum resources. For example, for a flexible grid network, the network may be divided into a plurality of sets of minimum pedigrees at a first interval, the usage state information of each minimum pedigree includes occupied and idle, and during the route calculation process, the pedigree in the idle state may be selected. The first interval may be 6.25GHz, and the present embodiment is not limited thereto.

Based on the above OTN network topology diagrams of fig. 1 to 2, the following provides various embodiments of the OTN route calculation method of the present invention.

As shown in fig. 3, fig. 3 is a flowchart of an OTN route calculation method according to an embodiment of the present invention, where the OTN route acquisition method includes, but is not limited to, step S310, step S320, and step S330.

Step S310, obtain the first service routing request.

In an embodiment, the first service in the acquired first service routing request may be a service establishment scenario or a service recovery scenario, which is not specifically limited in this embodiment.

Step S320, a first initial routing path is generated according to the first service routing request.

In an embodiment, a first initial routing path that meets routing constraint information of the first service routing request may be calculated by using a routing algorithm based on the resource information of the entire network according to the resource information of the first service routing request. The first initial routing path may include resource information such as each network element unit that passes through, network element connection port information, and a TE link that passes through and is connected to the network element connection port.

It should be noted that the routing algorithm used may be a K-best shortest path algorithm (KSP algorithm) or a digital signal processing algorithm (DSP algorithm), and the embodiment of the present application is not limited. In addition, as will be understood by those skilled in the art, the KSP algorithm and the DSP algorithm are commonly used in the art, and therefore, detailed description thereof is omitted here for the specific principles of the KSP algorithm and the DSP algorithm.

It should be noted that, if the step cannot calculate the available first initial routing path, it may be determined that the routing calculation fails, and the OTN routing calculation method is ended.

Step S330, updating the routing path of the first initial routing path in the network element according to the resource information of the network element through which the first initial routing path passes, so as to obtain a first target routing path.

In an embodiment, the resource information of the network element passed by the first initial routing path may be obtained according to the first initial routing path, the routing path of the first initial routing path in the network element is updated based on the resource information of the passed network element as a calculation basis, and the first target routing path is obtained.

In an embodiment, since the optical transport network route calculation method uses the above steps S310, S320 and S330, by acquiring the first traffic route request, a first initial routing path according with the routing constraint information of the first service routing request can be calculated according to the resource information of the first service routing request and based on the resource information of the whole network, obtaining the resource information of the network element passed by the first initial routing path according to the first initial routing path, updating the routing path of the first initial routing path in the network element on the basis of the calculation of the resource information of the passed network element, and obtaining a first target routing path, because the calculation of the first target routing path is based on the resource information of the network elements passing through, the routing algorithm is simplified compared with the routing algorithm based on the resource information of the network elements of the whole network, and the complexity of the OTN network routing calculation can be reduced, thereby improving the routing calculation efficiency.

Referring to fig. 4, in an embodiment, step S330 includes, but is not limited to, the following steps:

step S410, according to the resource information of the network element passed by the first initial routing path, generating a first resource topology respectively corresponding to each network element.

In an embodiment, the first resource topology respectively corresponding to each network element may be generated according to resource information of the network element through which the first initial routing path passes, that is, according to a usage condition of internal resources of the network element through which the first initial routing path passes, a connection relationship between the internal resources, and a usage condition of spectrum resources of a TE link between the network element and the network element through which the first initial routing path passes, and the first resource topology may be used as a routing path calculation basis in step S420.

Step S420, the resource information in each first resource topology is combined to obtain a second resource topology corresponding to each network element.

In an embodiment, the resource information in each first resource topology may be combined to obtain a second resource topology corresponding to each network element, which may simplify the resource information in the network elements, thereby reducing the complexity of the routing calculation of the OTN network, and improving the calculation efficiency of the routing.

Step S430, topology clipping is performed on each second resource topology, and resource expansion is performed on the resource information of the clipped second resource topology, so as to obtain a third resource topology corresponding to each network element.

In an embodiment, topology clipping may be performed on resource information in each second resource topology, resource information that does not meet the service information requirement of the first service may be clipped, resource information that meets the service information requirement of the first service is reserved, then resource expansion is performed on the resource information of the clipped second resource topology, a third resource topology corresponding to each network element is obtained, and effective clipping is performed on resource information that is irrelevant to the first service, so that resource information in the network elements can be effectively simplified, and therefore, the complexity of OTN routing calculation can be reduced, and the calculation efficiency of the routing is improved.

Step S440, updating the routing path of the first initial routing path in the network element according to the third resource topology corresponding to each network element, so as to obtain a first target routing path.

In an embodiment, the routing path of the first initial routing path in the network element can be quickly updated according to the simplified resource condition in the third resource topology corresponding to each network element and the service information requirement of the first service, the updated routing path can meet the requirement of the first service routing request, the first target routing path is obtained, and the simplified resource information in the third resource topology can improve the routing calculation efficiency of the subsequent service.

In an embodiment, since the optical transport network routing calculation method uses the steps S410, S420, S430, and S440, a first resource topology corresponding to each network element is obtained according to resource information of the network element through which the first initial routing path passes; then, the resource information in each first resource topology can be combined, so that the resource information in the network elements is simplified, and a second resource topology corresponding to each network element is obtained; the topology of the resource information in each second resource topology can be cut, the resource information which does not meet the requirement of the service information of the first service can be cut, the resource information which meets the requirement of the service information of the first service is reserved, and then the resource information of the cut second resource topology is subjected to resource expansion to obtain a third resource topology corresponding to each network element; according to the simplified resource condition in the third resource topology corresponding to each network element and the service information requirement of the first service, the routing path of the first initial routing path in the network element is quickly updated, the first target routing path can be obtained, and the simplified resource information in the third resource topology can improve the routing calculation efficiency of the subsequent service.

Referring also to fig. 5, in an embodiment, step S420 includes, but is not limited to, the following steps:

step S510, combining units in each first resource topology according to the function type and the connection attribute to obtain different function modules.

In an embodiment, the units in each first resource topology are classified according to the function type and the connection attribute, and the similar units are combined to obtain different function modules, so that the resource information in the first resource topology can be simplified, the complexity of the OTN network routing calculation is reduced, and the routing calculation efficiency is improved.

Step S520, establishing a connection relationship between different functional modules according to the connection relationship between adjacent units in the first resource topology, to obtain a second resource topology corresponding to each network element.

In an embodiment, for the functional module in the first resource topology after the unit combination is completed, the combined functional module is connected according to the connection relationship between the adjacent units in the first resource topology to obtain a second resource topology corresponding to each network element, the first resource topology is effectively simplified into the second resource topology, the complexity of the OTN network routing calculation is reduced, and thus the calculation efficiency of the routing can be effectively improved.

In an embodiment, referring to fig. 6, fig. 6 is a schematic diagram of a combination of units in a network element of an Optical transport network OTN, where the network element 600 includes an Optical power Amplifier (OBA), an Optical Pre-Amplifier (OPA), an Optical switch module 620, an Optical Multiplexer Unit (OMU), an Optical Demultiplexer Unit (ODU), and a circuit board.

An optical power amplifier board OBA, an optical preamplifier board OPA and an optical multiplexer unit OMU for signal input and output of the network element 600 may be combined to form a transmission port module 610 according to the function type and the connection attribute; the transport port module 610 may be connected to the TE link for the outside of the network element 600, and the transport port module 610 may be connected to other modules of the network element 600 through the optical switching module 620 for the inside of the network element 600.

It should be noted that the number of the transmission port modules 610 may be 1, 2, or 4, and this embodiment is not limited in particular.

In the network element 600, the circuit board is connected to the optical switching module 620 through the optical power amplification board OBA, the optical multiplexer unit OMU, and the optical demultiplexer unit ODU of the non-transmission port module 610, and different circuit boards may have the same connection mode, and different frequency spectrums are required for different services in the optical multiplexer unit OMU and the optical demultiplexer unit ODU, so that the connection relationship is consistent with a concept of a bus in a computing network, and the optical power amplification board OBA, the optical multiplexer unit OMU, and the optical demultiplexer unit ODU may be combined to form the internal transmission module 630 of the network element 600, which plays a role of an internal bus of the network element 600.

It should be noted that the internal transmission module 630 of the network element 600, which is formed by the optical multiplexer unit OMU, the optical power amplifier board OBA, and the optical demultiplexer unit ODU in the direction from the transmission port module 610 to the optical switch module 620 and then to the circuit board, may be referred to as an incoming direction-bus internal link; the bus internal link formed by the optical multiplexer unit OMU, the optical power amplifier board OBA, and the optical demultiplexer unit ODU from the circuit board to the optical switch module 620 and then to the transmission port module 610 is referred to as an outgoing direction-bus internal link.

The circuit boards in the network element 600 may be paired two by two to form a relay combination, and a plurality of relays may be combined to form the relay combination module 640. As shown in fig. 4, taking the network element 600 resource as an example, the network element 600 may form 10 relay combinations: { C11, C12}, { C12, C11}, { C21, C23}, { C21, C24}, { C23, C21}, { C24, C21}, { C22, C23}, { C22, C24}, { C23, C22} and { C24, C22 }.

It should be noted that the function types are to classify the units that can achieve the same or similar working content, for example, the optical power amplifier board OBA, the optical preamplifier board OPA and the optical multiplexer unit OMU can be used for transmitting data, and then the function types of the optical power amplifier board OBA, the optical preamplifier board OPA and the optical multiplexer unit OMU can be a transmission function type; for another example, the plurality of cells may be a plurality of circuit boards, and the circuit boards may be used for relaying, and then the function types of the plurality of circuit boards may be relay function types.

It is noted that the connection properties are classified according to the units/modules connected at both ends of the several units forming the functional link, for example, the OTN network includes a first network element, a second network element, and a bidirectional first TE link for connecting the first network element and the second network element, the first network element includes a first optical power amplifier board OBA, a first optical preamplifier board OPA, a first optical multiplexer unit OMU, and a first optical switch module 620, the first optical power amplifier board OBA and the first optical multiplexer unit OMU are connected to form an output port link of the first network element, the first optical preamplifier board OPA can form an input port link of the first network element, one end of the output port link and one end of the input port link are connected to the first optical switch module 620, and the other end of the output port link and the other end of the input port link are connected to the first TE link, it can be understood that the connection properties of the first optical power amplification panel OBA, the first optical multiplexer unit OMU and the first optical preamplifier OPA are the same.

It should be noted that the two boards in a trunking combination are connected to different internal transmission modules 630 of the network element 600, and therefore have different sequences, which indicate different trunking schemes, for example, { C11, C12} and { C12, C11} are trunking combinations of two different trunking schemes.

It should be noted that the structure of the network element 600 calculated by the OTN route calculation method in this application is not limited to the unit and the structure connection relationship in this embodiment, and may be set according to the actual situation, and this embodiment is not limited uniquely.

Referring additionally to fig. 7, in an embodiment, the topology clipping is performed on each second resource topology in step S430, which includes, but is not limited to, the following steps:

step S710, determining that the functional module in the second resource topology through which the first initial routing path passes is the first routing module.

In an embodiment, it may be determined that the function module in the second resource topology passed by the first initial routing path is the first routing module, that is, the function module in the second resource topology is classified into the first routing module and other function modules, and preliminary classification preparation is made for the step of performing topology pruning on the second resource topology.

Step S720, deleting the functional modules in the second resource topology except the first routing module.

In an embodiment, the functional modules in the first resource topology may be cut, the first routing module is reserved, and the other functional modules except the first routing module are deleted, so that the second resource topology is effectively simplified, the complexity of the OTN network routing calculation is reduced, and the routing calculation efficiency is improved.

In an embodiment, since the first initial routing path is determined and the transmission port module passed by the first initial routing path is also determined, the transmission port module passed by the non-first initial routing path is not used and does not affect the result of routing calculation, so that the transmission port module passed by the non-first initial routing path can be deleted, the second resource topology is effectively simplified, the complexity of routing calculation of the OTN network is reduced, and the calculation efficiency of the routing is improved.

In an embodiment, in the process of calculating the routing path of a single service, because the exactly same relay combinations are configured, and the roles of the relay combinations can be replaced with each other, one relay combination can be reserved for a plurality of relay combinations with exactly the same configuration, and topology tailoring processing can be performed on other relay combinations.

Step S730, determining the selected unit in the first routing module according to the service information carried in the first service routing request.

In an embodiment, the service information carried in the first service routing request may include information specifying a unit in the first routing module, so that the selected unit in the first routing module may be directly confirmed during route calculation, and preparation for topology tailoring is performed in advance.

Step S740, deleting the units except the selected unit in the first routing module to obtain the clipped second resource topology.

In an embodiment, in the process of route calculation, since the selected unit exists in the first routing module, other units except the selected unit are not selected, and the result of route calculation is not affected, so that other units in the module corresponding to the unit can be deleted.

In an embodiment, the service information in the first service routing request includes a line board of the source network element and a line board of the target network element, and since the line board of the source network element and the line board of the target network element are already specified, other line boards except the specified line board in the source network element and the target network element can be deleted without affecting the routing calculation result, so that the second resource topology can be effectively simplified, the complexity of the OTN network routing calculation is reduced, and the routing calculation efficiency is improved.

In addition, referring to fig. 8, in an embodiment, the resource expanding is performed on the resource information of the pruned second resource topology in step S430 to obtain a third resource topology corresponding to each network element, which includes but is not limited to the following steps:

step S810, performing resource expansion on the clipped second resource topology according to the service information carried in the first service routing request, to obtain a third resource topology corresponding to each network element.

In an embodiment, the resource information corresponding to the service information may be confirmed according to a requirement of the service information carried in the first service routing request, then the resource information of the second resource topology is subjected to resource expansion according to the resource information required by routing calculation, and the expanded resource topologies are connected according to a connection relationship between adjacent functional modules in the second resource topology, so that a third resource topology corresponding to each network element may be obtained.

In an embodiment, the relay combination module may be expanded into a plurality of relay virtual nodes according to the service information and the capability information supported by the relay combination module, the relay combination in each network element may be expanded into a plurality of relay virtual nodes according to the resource information, the resource information includes a line side rate and a modulation format, wherein the relay virtual nodes whose line side rate is less than the service rate are clipped, the relay virtual nodes whose line side rate is greater than the service rate are reserved, and the expanded relay virtual nodes are connected according to a connection relationship between adjacent functional modules in the second resource topology, so as to obtain a third resource topology corresponding to each network element.

It should be noted that, because each relay combination is composed of 2 circuit boards, the relay combination is used to terminate the previous segment of signal and generate a new segment of optical signal, and the resource information (i.e., the line-side rate and the modulation format) of the source network element and the target network element used by the two segments of optical signals may be different, each virtual node may be a combination of a manner in which the previous segment of optical signal is terminated and a manner in which the next segment of optical signal is started.

It is noted that the line boards of the upper and lower paths in the trunk combination can be developed in the same manner to indicate the start of the signal or the end of the signal.

It should be noted that, for a bidirectional service, the same spectrum, modulation format, and the like are used in the same trunk, and for an optical path in a network element, each group of OMU and ODU can only be used in one direction of the service, so that two circuit boards combined with each other need to connect links in different network element internal transmission modules.

In an embodiment, the idle spectrum resources of the TE link may be acquired, and then the transmission port module is expanded into a plurality of port virtual nodes according to the idle spectrum resources and the service information. For example: in flexible grid OTNs, the spectral widths typically used are 25GHz, 37.5GHz, 50GHz, 62.5GHz, 75GHz and 100 GHz. For each bidirectional TE link, if the spectrum width corresponding to one center frequency is usable, the corresponding virtual TE link may be expanded, the virtual TE port corresponding to the expanded virtual TE link may be expanded according to the expansion condition of the TE link, and in the same manner, the transmission port of the transmission port module may be expanded into the corresponding port virtual node according to the virtual TE port condition. Another example is: a transport port module with TE links connected with idle resources [193.0000THz,193.0375THz ], then the transport port module 610 can be expanded into 4 port virtual nodes according to the spectrum width requirement that can be used by the flexible grid: 25GHz- [193.0000THz,193.0250THz ], 25GHz- [193.00625THz,193.03125THz ], 25GHz- [193.0125THz,193.0375THz ], 37.5GHz- [193.0000THz,193.0375THz ].

In an embodiment, starting from a source network element, each virtual unit after resource expansion is connected by using a unidirectional line segment according to a first initial routing path, and connection conditions of two virtual nodes are as follows: and two adjacent virtual nodes on the first initial routing path are required to meet the spectrum consistency. For example, the OTN includes a first network element and a second network element, a port virtual node serving as an ingress in the first network element is connected to a port virtual node serving as an egress in the second network element through a virtual TE link, and a port virtual node serving as an ingress may be connected to a port virtual node serving as an egress in the first network element through a relay combination reachable inside a mesh point, so that a new third resource topology including the port virtual node and a virtual unidirectional link may be generated, and the new third resource topology may be used as a calculation basis for generating a target routing path resource. It should be noted that the weight of the link may be set to 1, and may be set to 2, and this embodiment is not particularly limited.

Referring also to fig. 9, in an embodiment, step S440 includes, but is not limited to, the following steps:

step S910, according to the third resource topology corresponding to each network element, a shortest path algorithm is adopted to perform calculation, and according to the calculation result, the routing path of the first initial routing path in the network element is updated, so that a first target routing path is obtained.

In an embodiment, according to the third resource topology corresponding to each network element, a shortest path algorithm may be used, and a combination of relays used for processing the uplink and downlink traffic in the source network element to a combination of relays used for processing the uplink and downlink traffic in the target network element may be obtained.

It should be noted that the resource information may be a line-side rate, may be a modulation format, may be a center frequency, or may be a spectral width, and the embodiment is not limited in particular.

It should be noted that if the shortest path algorithm fails to calculate, the calculation result indicates that the resource allocation scheme meeting the condition is not obtained, and the process may return to step S410, and a new second initial routing path may be calculated by using the K-best shortest path algorithm again.

It should be noted that the shortest path algorithm may adopt an a-shortest path algorithm or may also adopt a Dijkstra algorithm, and this embodiment is not limited in particular.

In addition, referring to fig. 10, in an embodiment, when acquiring the same service of a plurality of source network elements and a plurality of target network elements, after step S440, the method further includes the following steps:

step S1010, a second service routing request is obtained, and a source network element and a target network element corresponding to the second service routing request are consistent with a source network element and a target network element corresponding to the first service routing request;

step S1020, performing resource backtracking on the third resource topology according to the first target routing path, and generating a third target routing path that meets the second service routing request.

In an embodiment, when services identical to a plurality of source network elements and a plurality of target network elements are obtained, a third resource topology after resource expansion may be backtracked based on a result of a first target routing path of a first service routing request, a virtual node resource required by the first target routing path of the first service routing request may be eliminated on the basis of the third resource topology, then a remaining resource may be backtracked, a reachable unit meeting a resource requirement of a second service routing request may be obtained by backtracking, and a third target routing path meeting the second service routing request may be generated.

It should be noted that, if the number of the services is three, after the first target routing path of the first service and the third target routing path of the second service are confirmed, the resource backtracking may be performed on the third resource topology based on the results of the first target routing path of the first service and the third target routing path of the second service, so as to obtain the target routing path of the third service, and the obtained number of the services is not specifically limited in this embodiment.

It should be noted that when a batch of service routing requests are received, the service routing requests may be grouped, sorted according to the groups, and the routing paths of the services of each group are calculated in sequence. The grouping conditions were as follows: the source network element and the target network element in the service information are the same; the service rates are the same; the access modules of the upper and lower circuit boards in the source network element and the target network element are the same as the internal transmission modules of the access network element.

In an embodiment, when multiple services are obtained, multiple hops may be obtained according to a result of the target routing path of the first service routing request and a relay combination of the third resource topology. Calculating the idle frequency spectrum resources of the network element internal transmission module and the TE link passed by each relay section to obtain the intersection of the idle frequency spectrum resources of the network element internal transmission module and the TE link, namely obtaining { S }₁,S₂,...,S_nIn which S is_nRepresenting the intersection of the white space within the nth hop.

For each relay combination, calculating the number of relay combinations of the relay combination modules used in the result of the target routing path of the first service routing request in the network element corresponding to the relay combination. For example: the relay combination module used by the result of the target routing path of the first service routing request is a first relay combination, and if it is determined that a second relay combination can replace the first relay combination, the second relay combination needs to satisfy the following conditions: (1) the second relay combination module supports that the first relay combination module selects the resource of { line side rate, modulation format } in the result of the target routing path of the first service routing request; (2) the first relay combination module and the second relay combination module are connected with the same network element internal transmission module together; (3) the circuit board in the first relay combination module is different from the circuit board in the second relay combination module. Referring to the graph shown in fig. 6, assuming that the first trunking combination used as a result of the target routing path of the aforementioned first traffic routing request is C21, C23, it has an additional alternative second trunking combination that may be C22, C24.

And acquiring the spectrum width in the intersection of the available idle spectrum in each relay segment, calculating the maximum distributable service quantity, and measuring the minimum value of the maximum distributable service quantity and the number of the relay combination modules which can replace the relay combination in the relay segment to obtain the batch distributable service quantity in the relay segment. For example, setting T_nTo indicate the number of the batch allocable services in the nth hop, the total number of the batch allocable services is min { T }₁,T₂,...,T_nAnd, i.e. the minimum value of the number of services that can be allocated in batches in each hop.

It should be noted that if the result of the target routing path of the first service routing request does not use the relay combination, the maximum allocable service number may be calculated according to the service spectrum width by considering only the intersection of the available idle spectrum in the TE link. If the maximum allocable service number is larger than or equal to the acquired service number, all the acquired services can be successfully allocated with resources; if the maximum allocable service number is less than the acquired service number, allocating resources of the corresponding service based on the maximum allocable service number, and the rest services are services which cannot allocate paths in the route calculation.

And (4) listing the services of which the resources are successfully allocated into a calculation path success set, and listing the services of which the paths cannot be allocated in the route calculation into an uncomputed service set again, and performing cyclic calculation by using the steps until the uncomputed services are 0.

And summarizing the calculation path success set and the calculation path failure set to form a final calculation result of the batch service route path, and returning.

The above embodiments are described by steps of a route calculation process, and in order to make the objects, technical solutions, and advantages of the present invention more clearly understood, the OTN route calculation method of the present invention will be further described by the specific embodiments fusing the above steps.

In the first embodiment, when the number of the obtained service routing requests is 1 and the first initial routing path is successfully generated according to the service routing request, the OTN routing calculation method includes:

referring to the OTN network shown in fig. 2, the OTN network includes 4 network elements, which are a first network element S, a second network element B, a third network element C, and a fourth network element D, respectively, where the first network element S and the fourth network element D are respectively configured with 4 circuit boards, which can meet the uplink and downlink transmission requirements of a service; the second network element B is not provided with a circuit board and can be used as a straight-through passing site in the OTN; the third network element C configures 6 circuit boards, and configures the 6 circuit boards into 2 types of circuit boards, which can be used as service relays.

Referring to fig. 11, the OTN network topology includes a first network element S, a second network element B, a third network element C, and a fourth network element D, where the first network element S is connected to the second network element B and the third network element C, respectively, and the fourth network element D is connected to the second network element B and the third network element C, respectively, and link weights (TE-metrics) of each bidirectional TE link set between the two network elements are specifically as follows: the link weight of the TE link between the first network element S and the second network element B is 5, the link weight of the TE link between the second network element B and the fourth network element D is 5, the link weight of the TE link between the first network element S and the third network element C is 10, and the link weight of the TE link between the third network element C and the fourth network element D is 10.

Bidirectional TE link	Pedigree of availability
		S-B	[193.0375THz,193.1250THz]
S-C	[193.0000THz,193.1000THz]
		B-D	[193.0500THz,193.1000THz]
D-C	[193.0100THz,193.1500THz]

TABLE 1. available Spectrum resources for bidirectional TE links between network elements

It should be noted that, since the FEC type has a low influence on the spectral width of the line-side signal, the most basic FEC type is set to be used in this embodiment and the following embodiments.

The types of resources supported by each line board are shown in table 2:

service board label	{ Signal Rate, modulation Format, spectral Width }
		C11-Up/Down traffic	{100Gbps，QPSK，50GHz}，{200Gbps，QPSK，75GHz}
C12-Up/Down traffic	{100Gbps，QPSK，50GHz}
		C13-Up/Down traffic	{100Gbps，QPSK，50GHz}
C14-Up/Down traffic	{100Gbps，QPSK，50GHz}
		C21-Up/Down traffic	{100Gbps，QPSK，50GHz}，{200Gbps，QPSK，75GHz}
C22-Up/Down traffic	{100Gbps，QPSK，50GHz}
		C23-Up/Down traffic	{100Gbps，QPSK，50GHz}
C24-Up/Down traffic	{100Gbps，QPSK，50GHz}
		C31-Relay	{200Gbps，QPSK，75GHz}
C32-Relay	{200Gbps，QPSK，75GHz}
		C41-Relay	{100Gbps，QPSK，50GHz}
C42-Relay	{100Gbps，QPSK，50GHz}
		C43-Relay	{100Gbps，QPSK，50GHz}
C44-Relay	{100Gbps，QPSK，50GHz}

TABLE 2 list of supported signal types for each board

It is noted that all channels of the OMU and ODU in the network may be assumed to be idle and available in the full frequency domain.

Acquiring a first service routing request, wherein the first service information comprises: the source network element is a first network element S, the target network element is a fourth network element D, the client side signal type is OTU4(100Gbps), the upper and lower service boards of the source network element are designated to be C11, and the lower and upper service boards of the target network element are designated to be C21. The calculation scene of the routing path is a routing path calculation scene of a single service, and the routing path calculation process is as follows:

step one, adopting a K-best shortest path algorithm (KSP algorithm) to obtain a result of a first initial routing path, namely a first network element S, a second network element B and a fourth network element D;

and step two, generating a resource topology on the first initial routing path based on the available spectrum resources of the bidirectional TE link and the calculated result of the first initial routing path, and performing resource abstraction on the topology to complete topology cutting and resource deletion to obtain a result shown in fig. 12.

Referring to fig. 12, 101 is a circuit board for uplink and downlink services in a source network element (first network element S), and 301 is a circuit board for uplink and downlink services configured in a target network element (fourth network element D); an optical power amplifier board (OBA), an optical preamplifier board (OPA) and an Optical Multiplexer Unit (OMU) which are connected with a TE link between a first network element S and a second network element B in the first network element S can be abstracted and expanded into port virtual nodes according to different signal types and occupied frequency bands: 111 to 117 and 121, wherein 111 to 117 transmit signals 121 in {100Gbps, QPSK, 50GHz } manner and {200Gbps, QPSK, 75GHz } manner. With the same calculation method, the optical power amplifier board OBA, the optical preamplifier board OPA, and the optical multiplexer unit OMU in the second network element B, which are connected to the TE link between the first network element S and the second network element B, may be abstracted and expanded into port virtual nodes: 211, 217 and 221; in the second network element B, the optical power amplifier board OBA, the optical preamplifier board OPA, and the optical multiplexer unit OMU connected to the TE link between the second network element B and the fourth network element D may be abstracted and expanded into a port virtual node: 233, 237 and 241. The spectral width used by the port virtual node is shown in table 3. In the fourth network element D, the optical power amplifier board OBA, the optical preamplifier board OPA, and the optical multiplexer unit OMU connected to the TE link between the second network element B and the fourth network element D may be abstracted and expanded into a port virtual node: 313, 237 and 321; since the two port virtual nodes in the second network element B are connected through the optical switch module 620, the two port virtual nodes can be abstracted and expanded into virtual through links between the port virtual nodes representing the same signal type; the bidirectional TE link connected between the first network element S and the second network element B may be expanded into a plurality of virtual TE links between port virtual nodes connecting different network elements. The same calculation method can be applied to the bi-directional TE link between the second network element B and the fourth network element D. The network element internal transmission module 630 in the source network element (first network element S) and the target network element (fourth network element D) may expand the link between the circuit board of the up-and-down path and the corresponding port virtual node according to the usage of the resource. It is noted that the above generated connection lines are all unidirectional, originating from the source network element (first network element S) towards the target network element (fourth network element D).

Port virtual node label	Pedigree of availability
		111,211	[193.0375THz,193.0875THz]
112,212	[193.04375THz,193.09375THz]
		113,213,233,313	[193.0500THz,193.1000THz]
114,214,234,314	[193.05625THz,193.10625THz]
		115,215,235,315	[193.0625THz,193.1125THz]
116,216,236,316	[193.06775THz,193.11775THz]
		117,217,237,317	[193.0750THz,193.1250THz]
121,221,241,321	[193.0500THz,193.1250THz]

TABLE 3 virtual OA Port Signal frequency band

The number of port virtual nodes that can be split out by a transmission port depends on the intersection of the bi-directional TE link connected to the transmission port and the resources in the internal transmission module. Due to the resource limitation of the bidirectional TE link between the second network element B and the fourth network element D, the connection 211 cannot be made with the next stage of port virtual node.

And step three, calculating the shortest path from 101 to 301 by adopting a shortest path algorithm based on the clipped directional third resource topology obtained in the step two, and obtaining the first target routing path. Under the condition of no other constraint, one of the shortest equivalent paths obtained by calculation can be randomly selected, namely 101-113-213-233-313-301; the result of the first target routing path is a first network element S-a second network element B-a fourth network element D, the first target routing path has not been trunk combined, the line side signal type is 100Gbps, QPSK, 50GHz, and the spectrum is 193.0500THz,193.1000 THz.

The OTN routing calculation method according to the first embodiment can quickly update the routing path of the first initial routing path in the network element according to the simplified resource condition in the third resource topology corresponding to each network element and the service information requirement of the first service, the updated routing path can meet the requirement of the first service routing request, and the simplified resource information in the third resource topology can improve the routing calculation efficiency of the subsequent service.

In the second embodiment, when the number of the obtained service routing requests is 1 and the first initial routing path is successfully generated according to the service routing request, the OTN routing calculation method includes:

referring to the OTN network shown in fig. 2, the OTN network includes 4 network elements, which are a first network element S, a second network element B, a third network element C, and a fourth network element D, respectively, where the first network element S and the fourth network element D configure 4 circuit boards, and the 4 circuit boards can all support the uplink and downlink transmission requirements of the service; the second network element B is not provided with a circuit board and can be used as a straight-through passing site; the third network element C configures 6 circuit boards, and configures the 6 circuit boards into 2 types of circuit boards, which can be used as service relays.

In this embodiment, the available spectrum resources of each TE link are shown in table 4:

bidirectional TE link	Pedigree of availability
		S-B	[193.0750THz,193.1250THz]
S-C	[193.0250THz,193.1000THz]
		B-D	[193.1000THz,193.1500THz]
C-D	[193.0750THz,193.1250THz]

TABLE 4 available Spectrum resources for the two-way TE links in the second embodiment

It should be noted that, the resource information supported by each circuit board is shown in table 2, and it can be assumed that all channels of the OMU and ODU in the network are idle and available in the full frequency domain.

Acquiring a first service routing request, wherein the first service information comprises: the source network element is a first network element S, the target network element is a fourth network element D, the client side signal type is OTU4(100Gbps), the up-down service board of the source network element is designated as C11, and the down-up service board of the target network element is designated as C21. The calculation scene of the routing path is a routing path calculation scene of a single service, and the routing path calculation process is as follows:

step one, adopting a K optimal shortest path algorithm (KSP algorithm) to obtain an optimal first initial routing path result as a first network element S-a second network element B-a fourth network element D;

and step two, based on the available spectrum resources of the bidirectional TE link and the calculated result of the first initial routing path, generating a first resource topology on the first initial routing path, performing resource abstraction on the first resource topology to obtain a second resource topology, and completing topology clipping and resource deletion on the second resource topology to obtain a third resource topology, so as to obtain the result shown in fig. 13.

The signal types used by the port virtual node 111 and the port virtual node 211 are {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.0750THz,193.1250THz ], the signal types used by the port virtual node 231 and the port virtual node 311 are {100Gbps, QPSK, 50GHz }, and the frequency spectrum is [193.1000THz,193.1500THz ];

step three, adopting a shortest path algorithm to obtain an algorithm return failure result, namely no reachable path exists between the port virtual node 101 and the port virtual node 301;

step four, obtaining a second suboptimal initial routing path result first network element S-a third network element C-a fourth network element D by adopting a K optimal shortest path algorithm (KSP algorithm);

and step five, generating a first resource topology on a new second initial routing path based on the available spectrum resources of the bidirectional TE link and the calculated first initial routing path result, performing resource abstraction on the first resource topology to obtain a second resource topology, finishing clipping and resource deletion on the second resource topology to obtain a third resource topology, and obtaining a result shown in fig. 14. The signal frequency band used by the virtual node of each port is shown in table 5. The type of signal used by port virtual node 141 to port virtual node 144, port virtual node 441 to port virtual node 444, port virtual node 381, and port virtual node 481 is {100Gbps, QPSK, 50GHz }. The type of signal used by port virtual node 151 and port virtual node 451 is {200Gbps, QPSK, 75GHz }. The circuit board combination method corresponding to each relay combination is shown in table 6.

Port virtual node label	Frequency band of signals
		141,441	[193.0250THz,193.0750THz]
142,442	[193.03125THz,193.08125THz]
		143,443	[193.0375THz,193.875THz]
144,444	[193.04375THz,193.09375THz]
		151,451	[193.0500THz,193.1000THz]
381,481	[193.0750THz,193.1250THz]

TABLE 5 Port virtual node Signal frequency band

Relay combination label	Circuit board combination
		461	{C41，C43}{C42，C43}{C41，C44,}{C42，C44}
462	{C43，C41}{C43，C42}{C44，C41,}{C44，C42}
		471	{C31，C32}
472	{C32，C31}

TABLE 6 Circuit Board combinations represented by Relay combinations

Step six, a shortest path algorithm is adopted, and one routing path is randomly selected from the equivalent results without other constraint conditions, for example, the routing path of 101-. That is, the calculation result of the route is the first network element S-the third network element C-the fourth network element D, and the relay combination configured in the third network element C is passed through, the type of the line-side signal of the first network element S-the third network element C section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.0250THz,193.0750THz ], the type of the line-side signal of the third network element C-the fourth network element D section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.0750THz,193.1250THz ], a circuit board C41 and a circuit board C43 can be sequentially used as signal relays in the third network element C, and the passed optical multiplexer unit OMU and optical demultiplexer ODU are connected portions of the circuit boards C41 and C43. Wherein, the forward service (S- > D) enters from LR of the circuit board C31 and exits from LT of the circuit board C32 in the third network element C; reverse traffic (D- > S) enters via LR of line card C32 and exits via LT of line card C31 in the third network element C.

The OTN routing calculation method according to the second embodiment may perform recalculation according to the simplified resource condition in the third resource topology corresponding to each network element and the service information requirement of the first service, and may quickly update the routing path of the first initial routing path in the network element, where the updated routing path may meet the requirement of the first service routing request, and the simplified resource information in the third resource topology may improve the routing calculation efficiency of the subsequent service.

In a third embodiment, when a plurality of service routing requests are obtained, the OTN routing calculation method includes:

The available spectrum resources for each TE link are shown in table 7:

bidirectional TE link	Pedigree of availability
		S-B	[193.0750THz,193.2000THz]
S-C	[193.2000THz,193.3000THz]
		B-D	[193.1000THz,193.2500THz]
C-D	[193.3000THz,193.4000THz]

TABLE 7 available Spectrum resources for the bidirectional TE links in EXAMPLE III

The types of line-side signals supported by each line card are also shown in table 2.

Table 8 key information of each service in the batch service request in the third embodiment

In the resource information of the OTN network in the third embodiment, a batch of service routing requests is obtained, where the batch of service routing requests includes 4 independent service routing requests, key information in each service routing request is shown in table 8, a source network element is a first network element S, a target network element is a fourth network element D, a client-side signal type is OTU4(100Gbps), an upper and lower service board of the source network element is designated as C11, and a lower and upper service board of the target network element is designated as C21. At this time, the PCE enters a batch service path computation scenario, and the path computation flow is as follows:

step one, grouping the services in batches. The first service, the second service, the third service and the fourth service all meet the three conditions that the source network element and the target network element are the same, the client side speed is the same, and the uplink and downlink service boards in the source network element and the target network element are accessed into the same internal bus link. Therefore, the acquired 4 services can be grouped into the same group.

And step two, randomly selecting one of the services, taking the selection of the first service as an example, adopting a routing path calculation method of a single service, and obtaining a result of the first target routing path as a first network element S, a second network element B and a fourth network element D, wherein the intermediate network element (the second network element B) is not provided with a circuit board of a relay combination, the type of a line side signal is {100Gbps, QPSK, 50GHz }, and the frequency spectrum is [193.1000THz,193.1500THz ].

And step three, based on the routing path calculation result of the single service in the step two, performing resource backtracking on the third resource topology. In the second step, the routing path calculation result of the single service only includes one hop, where the hop includes each section of internal transmission module in the source network element (first network element S) and the target network element (fourth network element D), the TE link set between the first network element S and the second network element B, and the TE link set between the second network element B and the fourth network element D. Taking the intersection of the idle resources on the two internal transmission modules and the two TE links as [193.1000THz,193.2000THz ], 2 channels of 50GHz can be divided, that is, the resource allocation can be completed for the first service and the second service, but the resource allocation can not be performed for the third service and the fourth service. That is, in this step, the calculation of the target routing paths of the first service and the second service is successful, the first target routing path of the first service and the third target routing path of the second service are generated, and the calculation of the routing paths of the third service and the fourth service is failed. And updating corresponding topology resources on the OTN based on the successful resource allocation results of the first service and the second service. At this time, the available spectrum resources of the bidirectional TE link between the first network element S and the second network element B are [193.0750THz,193.1000THz ], the available spectrum resources of the bidirectional TE link between the second network element B and the fourth network element D are [193.2000THz,193.2500THz ], the input/output-internal transmission module shared by the circuit board C11, the circuit board C12, the circuit board C13, and the circuit board C14 in the first network element S is available except [193.1000THz,193.2000THz ], and the input/output-internal transmission module shared by the circuit board C21, the circuit board C22, the circuit board C23, and the circuit board C24 in the fourth network element D is available except [193.1000THz,193.2000THz ].

And step four, returning the third service and the fourth service which are failed to calculate the routing path to the original service grouping. And randomly extracting a service, for example, extracting a third service, may adopt a routing path calculation method of a single service, because there is no suitable resource to allocate under the first initial routing path. The suboptimal second initial routing path capable of successfully distributing resources can be obtained through calculation, the resource topology of the suboptimal second initial routing path is combined, cut and expanded, and the suboptimal second target routing path is obtained through calculation, and the result of the suboptimal second target routing path is as follows: the first network element S-the third network element C-the fourth network element D, after the trunk combination configured by the third network element C, the type of the line-side signal of the first network element S-the third network element C section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.2000THz,193.2500THz ], the type of the line-side signal of the third network element C-the fourth network element D section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.3000THz,193.3500THz ], and the trunk combination with the label 461 shown in table 6 can be determined in the third network element C.

And step five, based on the result of the route path calculation of the single service in the step four, performing resource backtracking based on a third resource topology of the second target route path which is suboptimal. In the trunk of the first network element S-the third network element C, the intersection of the available resources of the TE link between the internal transmission module in the source network element (the first network element S) and the first network element S-the third network element C is [193.2000THz,193.3000THz ]; in the trunk of the first network element S — the third network element C, the intersection of the available resources of the internal transmission module in the target network element (fourth network element D) and the TE link between the third network element C and the fourth network element D is [193.3000THz,193.4000THz ]; the maximum number of combinations that can be substituted for each other and do not reuse the circuit board within the relay combination designated by reference numeral 461 is 2. Therefore, according to the result of the route path calculation in the step four, resources can be allocated to the third service and the fourth service, and the target route path of the fourth service is regenerated.

Step six, all the services are successfully distributed with resources through the routing path calculation method, and the result of distributing the resources is as follows:

the result of the calculation of the target routing path of the first service (i.e. the first target routing path in the above step three) is the first network element S-the second network element B-the fourth network element D, the second network element B is not configured with a trunk combination, the type of the line-side signal is {100Gbps, QPSK, 50GHz }, and the frequency spectrum is [193.1000THz,193.1500THz ];

the result of the calculation of the target routing path of the second service (i.e. the third target routing path in the above step three) is the first network element S-the second network element B-the fourth network element D, the second network element B is not configured with a trunk combination, the type of the line-side signal is {100Gbps, QPSK, 50GHz }, and the frequency spectrum is [193.1500THz,193.2000THz ];

the result of the calculation of the target routing path of the third service (i.e., the second target routing path in the fourth step) is the first network element S-the third network element C-the fourth network element D, and the relay combination configured in the third network element C is performed, the type of the line-side signal of the first network element S-the third network element C section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.2000THz,193.2500THz ], the type of the line-side signal of the third network element C-the fourth network element D section is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.3000THz,193.3500THz ], in the third network element C, the circuit board 41 and the circuit board 43 are sequentially used as signal relays, and the optical multiplexer unit OMU and the optical demultiplexer unit of the internal transmission module 630 of the network element that pass through are connected to the circuit board 41 and the circuit board 43.

The result of the calculation of the target routing path of the fourth service is that the first network element S-the third network element C-the fourth network element D passes through the relay combination configured in the third network element C, the type of the line-side signal of the first network element S-the third network element C segment is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.2500THz,193.3000THz ], the type of the line-side signal of the third network element C-the fourth network element D segment is {100Gbps, QPSK, 50GHz }, the frequency spectrum is [193.3500THz,193.4000THz ], in the third network element C, the circuit board 42 and the circuit board 44 are sequentially used as signal relays, and the optical multiplexer unit OMU and the optical multiplexer unit ODU of the network element internal transmission module 630 that pass through are connected to the circuit board 42 and the circuit board 44.

And summarizing the results of the target routing path calculation of the first service, the second service, the third service and the fourth service to form the result of the batch service routing path calculation and reply.

In the example of fig. 15, the apparatus 1500 includes a memory 1510 and a processor 1520, where the memory 1510 and the processor 1520 may be connected by a bus or otherwise, and fig. 15 exemplifies connection by a bus.

The memory 1510 is one type of non-transitory computer readable storage medium that can be used to store non-transitory software programs as well as non-transitory computer executable programs. Further, the memory 1510 may include high speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid state storage device. In some embodiments, the memory 1510 optionally includes memory remotely located from the processor 1520, and such remote memory may be coupled to the device 1500 via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Those skilled in the art will appreciate that the apparatus 1500 may be applied to various network controllers or network managers, and the embodiment is not particularly limited thereto. In addition, the network controller or the network manager having the apparatus 1500 may be applied to various optical transmission network systems, for example, an automatic switched optical network, a software defined network, and a subsequently evolved optical transmission communication network system, and the present embodiment is not limited thereto.

Those skilled in the art will appreciate that the apparatus 1500 shown in FIG. 15 is not intended to limit embodiments of the invention and may include more or less components than shown, or some components in combination, or a different arrangement of components.

In the apparatus 1500 shown in fig. 15, the processor 1520 may employ a data processing program stored in the memory 1510 to perform the optical transport network route acquisition method.

Furthermore, an embodiment of the present invention also provides a computer-readable storage medium, which stores computer-executable instructions, which are executed by one or more control processors, for example, by one of the control processors in fig. 15, and can cause the one or more control processors to execute the control method in the above-described method embodiment, for example, execute the above-described method steps S310 to S330 in fig. 3, method steps S410 to S440 in fig. 4, method steps S510 to S520 in fig. 5, method steps S710 to S740 in fig. 7, method step S810 in fig. 8, method step S910 in fig. 9, and method steps S1010 to S1020 in fig. 10.

One of ordinary skill in the art will appreciate that all or some of the steps, systems, and methods disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on computer readable media, which may include computer storage media (or non-transitory media) and communication media (or transitory media). The term computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data, as is well known to those of ordinary skill in the art. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can accessed by a computer. In addition, communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media as known to those skilled in the art.

The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, and are not to be construed as limiting the scope of the invention. Any modifications, equivalents and improvements which may occur to those skilled in the art without departing from the scope and spirit of the present invention are intended to be within the scope of the claims.

Claims

1. An OTN route calculation method for an optical transport network comprises the following steps:

acquiring a first service routing request;

2. The OTN routing computation method according to claim 1, wherein the updating the routing path of the first initial routing path in the network element according to the resource information of the network element through which the first initial routing path passes, to obtain the first target routing path, comprises:

generating a first resource topology corresponding to each network element according to the resource information of the network element passed by the first initial routing path;

combining the resource information in each first resource topology to obtain a second resource topology corresponding to each network element;

performing topology clipping on each second resource topology, and performing resource expansion on the clipped resource information of the second resource topology to obtain a third resource topology corresponding to each network element;

and updating the routing path of the first initial routing path in the network element according to the third resource topology corresponding to each network element to obtain a first target routing path.

3. The OTN routing computation method of claim 2, wherein the combining the resource information in each of the first resource topologies to obtain a second resource topology corresponding to each of the network elements comprises:

combining units in each first resource topology according to function types and connection attributes to obtain different function modules;

and establishing the connection relation between the different functional modules according to the connection relation between the adjacent units in the first resource topology to obtain a second resource topology corresponding to each network element.

4. The OTN route calculation method of claim 3, wherein said topology tailoring of each of said second resource topologies comprises:

determining that the functional module in the second resource topology through which the first initial routing path passes is a first routing module;

deleting functional modules in the second resource topology except the first routing module;

determining a selected unit in the first routing module according to the service information carried in the first service routing request;

and deleting the units except the selected unit in the first routing module to obtain the clipped second resource topology.

5. The OTN routing computation method of claim 4, wherein the performing resource expansion on the clipped resource information of the second resource topology to obtain a third resource topology corresponding to each network element comprises:

and performing resource expansion on the resource information of the second resource topology after being cut according to the service information carried in the first service routing request to obtain a third resource topology corresponding to each network element.

6. The OTN routing computation method according to claim 5, wherein the first routing module in the pruned second resource topology includes a relay combination module, and performing resource expansion on the pruned second resource topology according to the service information carried in the first service routing request includes:

and expanding the relay combination module into a plurality of relay virtual nodes according to the service information and the capability information supported by the relay combination module.

7. The OTN routing computation method according to claim 5, wherein the first routing module in the pruned second resource topology further includes a traffic engineering TE link and a transmission port module corresponding to the TE link, and performing resource expansion on the pruned second resource topology according to the service information carried in the first service routing request includes:

acquiring idle spectrum resources of the TE link;

and expanding the transmission port module into a plurality of port virtual nodes according to the idle spectrum resources and the service information.

8. The OTN route calculation method according to claim 7, wherein the expanding the transmission port module into a plurality of port virtual nodes according to the idle spectrum resources and the service information comprises:

and expanding the transmission port module into a plurality of port virtual nodes according to the center frequency of the idle spectrum resource and the service information.

9. The OTN route calculation method according to claim 1, wherein the generating a first initial routing path according to the first traffic routing request comprises:

and generating a first initial routing path by adopting a K-best shortest path algorithm according to the first service routing request.

10. The OTN route calculation method according to claim 2, wherein the updating the routing path of the first initial routing path in the network element according to the third resource topology corresponding to each network element to obtain a first target routing path comprises:

and updating the routing path of the first initial routing path in the network element by adopting a shortest path algorithm according to the third resource topology corresponding to each network element to obtain a first target routing path.

11. The OTN route calculation method according to claim 10, further comprising:

and when the first target routing path cannot be obtained, according to the first service routing request, a second initial routing path is regenerated by adopting a K-best shortest path algorithm, and according to the resource information of the network element through which the second initial routing path passes, the routing path of the second initial routing path in the network element is updated, so that the second target routing path is obtained.

12. The OTN route calculation method according to claim 2, further comprising:

acquiring a second service routing request, wherein a source network element and a target network element corresponding to the second service routing request are consistent with a source network element and a target network element corresponding to the first service routing request;

and performing resource backtracking on the third resource topology according to the first target routing path to generate a third target routing path which accords with the second service routing request.

13. The OTN route calculation method according to claim 12, wherein the resource tracing the third resource topology according to the first target route path to generate a third target route path that meets the second service route request includes:

excluding resource information of a network element through which the first target routing path passes in the third resource topology;

and generating a third target routing path which accords with the second service routing request according to the residual resource information in the third resource topology.

14. An apparatus, comprising: memory, processor and computer program stored on the memory and executable on the processor, characterized in that the processor implements the OTN route calculation method according to any of claims 1 to 13 when executing the computer program.

15. A computer-readable storage medium storing computer-executable instructions for performing the OTN routing computation method of any one of claims 1 to 13.