Space division multiplexing optical network protection resource allocation method based on preset circle

Abstract

The invention discloses a space division multiplexing optical network protection resource allocation method based on a preset circle. According to the method, the candidate preset circle set is generated based on the total service bandwidth of the link in the space division multiplexing optical network, the available idle protection resources and the optical network topology, the protection resources provided by the candidate preset circle set are determined, the candidate preset circles generated in the selection mode are small in number, high in quality and low in algorithm complexity, and the method is suitable for large-scale popularization and application. Then all target preset circles are selected from the candidate preset circle set in combination with the service total bandwidth of each selected link, and finally a target preset circle set is obtained, so that the links on the circles can be protected, the bridging links can be protected, and meanwhile, other links with smaller service total bandwidth can be protected; that is, the target preset circle set can efficiently perform protection resource allocation on the space division multiplexing optical network, the protection resource utilization rate is high, the protection requirements of all service requests can be met, and the protection efficiency is high.

Description

Technical Field

[0001] The present invention specifically relates to a space division multiplexing optical network protection resource allocation method based on preset circles. Background Art

[0002] Space division multiplexing technology refers to a method of multiplexing by using space division. Specifically, multiple optical fibers are combined into bundles to achieve space division multiplexing, or space division multiplexing is achieved in the same optical fiber, so that the same frequency band can be reused in different spaces, thereby increasing the capacity of the optical fiber transmission system by an order of magnitude. Multi-core optical fiber technology is one of the channel processing methods to achieve space division multiplexing technology. It can allow multiple signals to be transmitted independently along different fiber cores. However, sometimes network failures can cause a large amount of data loss, causing great losses to network operators. It is necessary to protect the transmission path of the network.

[0003] However, traditional protection schemes cannot meet the protection requirements of all service requests, use a large number of idle protection resources, and cannot efficiently allocate protection resources for space-division multiplexing optical networks;

[0004] Therefore, it is necessary to invent a method for allocating protection resources in a space-division multiplexing optical network based on a preset circle to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method for allocating protection resources in a space-division multiplexing optical network based on preset circles. The target preset circle set Z obtained by the present invention is * It can not only protect the link on the circle, but also protect the cross-link, and can also provide protection for other links with smaller total bandwidth of services, that is, the target preset circle set Z * The protection resource allocation for the space-division multiplexing optical network can be performed efficiently, the protection resource utilization rate is high, the protection requirements of all business requests can be met, and the protection efficiency is high, so as to solve the above-mentioned deficiencies in the technology.

[0006] In order to achieve the above object, the present invention provides the following technical solution: a method for allocating protection resources of a space-division multiplexing optical network based on a preset circle, comprising the following steps:

[0007] Step 1, obtaining the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network;

[0008] Step 2: Set y e It is the idle protection resource available on each link in the space-division multiplexing optical network;

[0009] Step 3: Generate a candidate preset circle set based on the total service bandwidth of the link, available idle protection resources, and optical network topology, and determine the protection resources provided by the candidate preset circle set;

[0010] Step 4: According to the protection resources provided by the candidate preset circle set, the target preset circle is determined based on the total service bandwidth.

[0011] In the aforementioned method for allocating protection resources of a space-division multiplexing optical network based on a preset circle, in step 1, the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network is obtained, and the specific steps are as follows:

[0012] 1.2. Let G(V,E,C) be a space-division multiplexing optical network, and R be the set of all service requests in G;

[0013] Where V is the set of nodes in the network topology;

[0014] E is a set of directed links;

[0015] C is the core collection;

[0016] 1.2, set is the bandwidth of r in the cth fiber core on link e;

[0017] Among them, e∈E, is the e-th link in G,

[0018] c∈C, is the cth fiber core in G;

[0019] 1.3, the calculation formula for the total service bandwidth of service requests in all fiber cores on each link is as follows:

[0020]

[0021] Among them, r∈R is the rth service request in G.

[0022] In the aforementioned method for allocating protection resources in a space-division multiplexing optical network based on a preset circle, in step 2,

[0023] Among them, the idle protection resource set of each link in the space-division multiplexing optical network is F,

[0024] And f∈F, is the fth spectrum resource on each link,

[0025] |F| is the maximum idle protection resource on each link;

[0026] Among them, the available idle protection resources y on each link e Less than the maximum space on each link

[0027] Idle protection resource |F|, that is:

[0028] y e ≤|F|.

[0029] In the aforementioned method for allocating protection resources in a space-division multiplexing optical network based on a preset circle, in step 3, a candidate preset circle set is generated according to the total service bandwidth of the link, the available idle protection resources, and the optical network topology, and the protection resources provided by the candidate preset circle set are determined. The specific steps are as follows:

[0030] 3.1. Arrange all links in the space-division multiplexing optical network in descending order according to the size of their total service bandwidth;

[0031] 3.2. In a link, select any node v at both ends of the link in descending order and perform depth-first search to obtain all possible set circles Q whose starting and ending points are both v and whose path length is greater than 3, and sort them in ascending order according to the path length of the set circles Q;

[0032] Among them, v∈V is a node in the network topology;

[0033] 3.3. Select the single circle q in ascending order in turn. If the idle protection resources of the single circle q can provide protection for the link, select it as the candidate preset circle;

[0034] Among them, q∈Q is a circle in the set circle Q;

[0035] 3.4. Repeat steps 3.2-3.3 for the remaining links, and organize the selected candidate preset circles in a unified manner to generate a candidate preset circle set Z;

[0036] 3.5. Based on the candidate preset circle set Z, determine the protection resources provided by it.

[0037] In the aforementioned method for allocating protection resources in a space-division multiplexing optical network based on preset circles, in step 3.5, based on the candidate preset circle set Z, the protection resources provided by it are determined, specifically:

[0038] When the candidate preset circle set Z is determined, the protection resources it provides are all circle links and all cross links;

[0039] The services that can be protected by the candidate preset circle set Z include: all circle uplinks constituting the candidate preset circle set Z and the cross-links formed by all nodes of the candidate preset circle set Z.

[0040] In the aforementioned method for allocating protection resources in a space-division multiplexing optical network based on preset circles, in step 4, the target preset circle is determined based on the total service bandwidth according to the protection resources provided by the candidate preset circle set. The specific steps are as follows:

[0041] 4.1. Total bandwidth x of services on all links e Sort in descending order, and select each link in turn according to the sorting;

[0042] 4.2. Let the target preset circle set be Z*. If Z* is not empty, then select the service total bandwidth x of the selected link in Z*. e Provide protection for the preset target circle z and update the total service bandwidth of link e to be protected to x e ;

[0043] 4.3. If the total service bandwidth of the selected link is x e > 0, the candidate preset circle set Z is selected in descending order of the number of links on its own circle, and the total service bandwidth x of the selected link is selected in turn. e Provides a target preset circle z for protecting resources;

[0044] 4.4. All selected target preset circles z are organized into a set to obtain the target preset circle set Z. * .

[0045] In the above-mentioned method for allocating protection resources in a space-division multiplexing optical network based on preset circles, in step 4.2, the target preset circle set is set to Z*. If Z* is not empty, then a service total bandwidth x of the selected link is selected from Z*. e Provide protection for the preset target circle z and update the total service bandwidth of link e to be protected to x e , specifically:

[0046] Assume the target preset circle z is the total service bandwidth x of the selected link e The protection resources provided are at this time:

[0047] like This means that the target preset circle z can be x e Provide sufficient protection resources to update x e =0;

[0048] like This means that the target preset circle z cannot be x e Provide adequate protection resources, update

[0049] Wherein, Z*∈Z, indicates that the target preset circle set Z* is selected from the candidate preset circle set Z, and z∈Z* is an element of Z*.

[0050] In the above-mentioned method for allocating protection resources in a space-division multiplexing optical network based on a preset circle, in step 4.3, if the total service bandwidth x of the selected link is e > 0, the candidate preset circle set Z is selected in descending order of the number of links on its own circle, and the total service bandwidth x of the selected link is selected in turn. e Provide a target preset circle z for protecting resources. The specific steps are:

[0051] 4.3.1. The candidate preset circle set Z is sorted in descending order according to the number of links in its own circle. Let the total service bandwidth x of the links selected by each target preset circle z be e The protection resources provided are Idle protection resources are

[0052] 4.3.2. Get the total service bandwidth x of the selected link e , confirm that the selected link is a link on the target preset circle z, or a cross-link;

[0053] 4.3.3. If it is a circle link, x e With y e Compare the sizes and select the target preset circle z;

[0054] 4.3.4. If it is a cross-link, With y e Compare the sizes and select the target preset circle z.

[0055] In the above-mentioned method for allocating protection resources of space-division multiplexing optical networks based on preset circles, in step 4.3.3, if it is a circle uplink, x e With y e Compare the sizes and select the target preset circle z, specifically:

[0056] If x e <y e , indicating that the protection resources provided by the current target preset circle z can fully protect x e , that is, the target preset circle z is successfully selected;

[0057] And the target preset circle z is x e Protection resources provided

[0058] The target preset circle z is x e Idle protection resources provided

[0059] Update the available idle protection resources on the currently selected link

[0060] Among them, if x e >y e , indicating that the protection resources provided by the current target preset circle z cannot fully protect x e , can only provide y e of conservation resources;

[0061] Then the target preset circle z is x e The protection resources provided are

[0062] The target preset circle z is xe The idle protection resources provided are

[0063] Update the available idle protection resources on the currently selected link to

[0064] Reselect other target preset circles z in the candidate preset circle set Z to provide (x e -y e ) until x is met e <y e , successfully selected the target preset circle z.

[0065] In the above-mentioned method for allocating protection resources of space-division multiplexing optical network based on preset circles, in step 4.3.4, if it is a cross-link, With y e Compare the sizes and select the target preset circle z, specifically:

[0066] Among them, if Indicates that the current target preset circle z protection resources can fully protect x e , that is, the target preset circle z is successfully selected;

[0067] And the target preset circle z is x e Protection resources provided

[0068] And the target preset circle z is x′ e The idle protection resources provided are

[0069] Updates the total protection resources available on the currently selected link

[0070] Among them, if Indicates that the current target preset circle z protection resources cannot fully protect x e , can only provide 2y e of conservation resources;

[0071] Then the target preset circle z is x e The protection resources provided are

[0072] The target preset circle z is x e The idle protection resources provided are

[0073] Update the total protection resources available on the currently selected link to

[0074] Reselect other target preset circles z in the candidate preset circle set Z to provide (xe -2y e ) until the protection resource is met The target preset circle z is successfully selected.

[0075] Compared with the prior art, the present invention has the following beneficial effects:

[0076] The present invention generates a candidate preset circle set based on the total service bandwidth of the link in the space-division multiplexing optical network, available idle protection resources, and optical network topology, and determines the protection resources provided by the candidate preset circles. The candidate preset circles generated by the selection method are small in number, high in quality, and low in algorithm complexity. Then, all target preset circles are selected from the candidate preset circle set in combination with the total service bandwidth of each selected link, and finally a target preset circle set is obtained. The target preset circle set can not only protect the link on the circle, but also protect the cross-link, and can also provide protection for other links with smaller total service bandwidths. That is, the target preset circle set can efficiently allocate protection resources to the space-division multiplexing optical network, and the protection resource utilization rate is high, and the protection requirements of all service requests can be met, and the protection efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0078] Figure 1 A network topology diagram with six nodes and eight edges of the present invention;

[0079] Figure 2 It is a schematic diagram of the structure of three fiber cores in the present invention;

[0080] Figure 3 The present invention is based on Figure 1 Demonstration diagram of the three preset circles generated;

[0081] Figure 4 is a flow chart of the present invention;

[0082] Figure 5 This is a schematic diagram of idle protection resource allocation according to the present invention. DETAILED DESCRIPTION

[0083] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0084] The present invention provides Figure 1-5 A method for allocating protection resources in a space-division multiplexing optical network based on a preset circle is shown, comprising the following steps:

[0085] Step 1: Obtain the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network. The specific steps are as follows:

[0086] 1.1. Let G(V,E,C) be a space-division multiplexing optical network, and R be the set of all service requests in G;

[0087] Where V is the set of nodes in the network topology;

[0088] E is a set of directed links;

[0089] C is the core collection;

[0090] 1.2, set is the bandwidth of r in the cth fiber core on link e;

[0091] Among them, e∈E, is the e-th link in G,

[0092] c∈C, is the cth fiber core in G,

[0093] r∈R, is the rth service request in G;

[0094] 1.3, the calculation formula for the total service bandwidth of service requests in all fiber cores on each link is as follows:

[0095]

[0096] For example: when the set R of all business requests contains 3 business requests;

[0097] And request r1 respectively, its source node is v1, the destination node is v3, and the requested bandwidth is 10 units of spectrum resources;

[0098] Request r2, whose source node is v1, destination node is v4, and the requested bandwidth is 5 units of spectrum resources;

[0099] Request r1, whose source node is v2 and destination node is v4, requests a bandwidth of 25 units of spectrum resources;

[0100] At this time, for the set R of all service requests, its service path is as follows Figure 3 As shown, it can be seen that: request r1 passes through the core c3 of link e1 and the core c3 of e2;

[0101] Request r2 passes through the core c3 of link e1, the core c3 of e2, and the core c3 of e3;

[0102] Request r3 passes through the core c1 of the core of link e4;

[0103] Therefore, the service bandwidth contained in the third fiber core on link e1, that is, the bandwidth of service request r1, can be expressed as The service bandwidth that needs to be protected is 10 units of spectrum resources;

[0104] The bandwidth of service request r2 can be expressed as The service bandwidth that needs to be protected is 5 units of spectrum resources;

[0105] The service bandwidth contained in the third fiber core on link e2, that is, the bandwidth of service request r1, can be expressed as The service bandwidth that needs to be protected is 10 units of spectrum resources;

[0106] The bandwidth of service request r2 can be expressed as The service bandwidth that needs to be protected is 5 units of spectrum resources;

[0107] The service bandwidth contained in the third fiber core on link e3, that is, the bandwidth of service request r2, can be expressed as The service bandwidth that needs to be protected is 5 units of spectrum resources;

[0108] The service bandwidth contained in the first core on link e4, that is, the bandwidth of service request r3, can be expressed as The service bandwidth that needs to be protected is 25 units of spectrum resources;

[0109] Then the service bandwidth contained in the third fiber core on link e1 is:

[0110] Then the service bandwidth contained in the third fiber core on link e2 is:

[0111] Then the service bandwidth contained in the third fiber core on link e3 is:

[0112] Then the service bandwidth contained in the third fiber core on link e4 is:

[0113] That is, link e1:x 1 =15; link e2: x 2 =15; link e3:x 3 =5; link e4: x 4 =25;

[0114] In summary, the above calculation formula for the total service bandwidth of service requests in all fiber cores on each link can be obtained.

[0115] In this step, the service bandwidth of all service requests in the links and fiber cores passed through in their service paths is calculated to obtain the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network. The total service bandwidth on the link is protected as a whole in a preset circle, and the total service bandwidth in the link that needs to be protected by the preset circle is clarified.

[0116] Step 2: Set y e It is the idle protection resource available on each link in the space-division multiplexing optical network;

[0117] Among them, the idle protection resource set of each link in the space-division multiplexing optical network is F,

[0118] And f∈F, is the fth spectrum resource on each link,

[0119] |F| is the maximum idle protection resource on each link;

[0120] Among them, the idle protection resource y on each link e Less than the maximum idle protection resource |F| on each link, that is:

[0121] y e ≤|F|;

[0122] In this step, available idle protection resources on each link of the space-division multiplexing optical network, that is, the number of available spectrum resources on each link, are obtained, thereby providing available idle protection resources for protection resource allocation of the preset circle in the subsequent steps.

[0123] Step 3: According to the total service bandwidth of the link, the available idle protection resources, and the optical network topology, a candidate preset circle set is generated and the protection resources provided by it are determined. The specific steps are as follows:

[0124] Wherein, the network topology includes a set of nodes and a set of directed links in the optical network topology;

[0125] 3.1. Arrange all links in the space-division multiplexing optical network in descending order according to the size of their total service bandwidth;

[0126] 3.2. In a link, select any node v at both ends of the link in descending order and perform depth-first search to obtain all possible set circles Q whose starting and ending points are both v and whose path length is greater than 3, and sort them in ascending order according to the path length of the set circles Q;

[0127] Among them, v∈V is a node in the network topology;

[0128] 3.3. Select the single circle q in ascending order in turn. If the available idle protection resources of the single circle q can provide protection for the link, then select it as the candidate preset circle;

[0129] Among them, q∈Q is a circle in the set circle Q;

[0130] And the available idle protection resources of the single circle q are the minimum value of the available idle protection resources of all links constituting the single circle q;

[0131] 3.4. Repeat steps 3.2-3.3 for the remaining links, and organize the selected candidate preset circles in a unified manner to generate a candidate preset circle set Z;

[0132] 3.5. Based on the candidate preset circle set Z, determine the protection resources provided by it, specifically:

[0133] When the candidate preset circle set Z is determined, the protection resources it provides are all circle links and all cross links;

[0134] The services that can be protected by the candidate preset circle set Z include: all the circle uplinks constituting the candidate preset circle set Z and the cross-links consisting of all the nodes of the candidate preset circle set Z;

[0135] For example: Figure 3 As shown, there are three candidate preset circles z, namely z1, z2, and z3. Figure 3 It can be concluded that the circle links of the preset circle z1 include e1, e2, e3, e5, e7, and e8;

[0136] The links on the preset circle z2 include e1, e4, e5, and e6;

[0137] The links on the preset circle z3 include e2, e3, and e4;

[0138] The preset circle z1 can protect the cross-links e4, e6, and the links e1, e2, e3, e5, e7, e8 on the circle;

[0139] The preset circle z2 can only protect the links e1, e4, e5, and e6 on the circle;

[0140] The preset circle z3 can only protect the links e2, e3, and e4 on the circle;

[0141] The protection resources provided by the preset circle z1 for the crossover links e4 and e6 are twice as much as those provided by the links e1, e2, e3, e5, e7 and e8 on the circle;

[0142] In this step, by first considering the link with a larger total service bandwidth, all single circles q that can provide protection for it are generated based on the optical network topology to obtain the collective circle Q, and then all single circles q are screened according to the length of the collective circle Q and the available idle protection resources to obtain the candidate preset circle. This method not only considers the optical network topology, but also considers the total service bandwidth and available idle protection resources on the link, avoiding a large number of candidate preset circles, thereby effectively reducing the complexity of the algorithm while ensuring the quality of the candidate preset circles;

[0143] Meanwhile, the protection resources provided by the candidate preset circle set Z for the cross-link are twice the protection resources provided by the set circle Q on the link, which can better provide protection resources for the cross-link.

[0144] Step 4: Determine the target preset circle based on the total service bandwidth according to the protection resources provided by the candidate preset circle set. The specific steps are as follows:

[0145] 4.1. Total bandwidth x of services on all links e Sort in descending order, and select each link in turn according to the sorting;

[0146] Example: When the links are sorted in descending order according to their total service bandwidth, we can get:

[0147] Link e4:x 4 =25, that is, when link e4 is selected, the total service bandwidth to be protected is 25;

[0148] Link e1:x 1 =15, that is, when link e1 is selected, the total service bandwidth to be protected is 15;

[0149] Link e2:x 2 =15, that is, when link e2 is selected, the total service bandwidth to be protected is 15;

[0150] Link e3:x 3 =5, that is, when link e3 is selected, the total bandwidth of the services to be protected is 5;

[0151] 4.2. Let the target preset circle set be Z*. If Z* is not empty, then select the service total bandwidth x of the selected link in Z*. e Provide protection for the preset target circle z and update the total service bandwidth of link e to be protected to x e , specifically:

[0152] Assume the target preset circle z is the total service bandwidth x of the selected link e The protection resources provided are At this time, if This means that the target preset circle z can be xe Provide sufficient protection resources to update x e =0;

[0153] like This means that the target preset circle z cannot be x e Provide adequate protection resources, update

[0154] Wherein, Z*∈Z, indicates that the target preset circle set Z* is selected from the candidate preset circle set Z, and z∈Z*, is an element of Z*;

[0155] 4.3. If the total service bandwidth of the selected link is x e > 0, the candidate preset circle set Z is selected in descending order of the number of links on its own circle, and the total service bandwidth x of the selected link is selected in turn. e Provide a target preset circle z for protecting resources. The specific steps are:

[0156] 4.3.1. The candidate preset circle set Z is sorted in descending order according to the number of links in its own circle. Let the total service bandwidth x of the links selected by each target preset circle z be e The protection resources provided are Idle protection resources are

[0157] 4.3.2. Get the total service bandwidth x of the selected link e , confirm that the selected link is a link on the target preset circle z, or a cross-link;

[0158] 4.3.3. If it is a circle link, x e With y e Compare the sizes and select the target preset circle z, specifically:

[0159] If x e <y e , indicating that the protection resources provided by the current target preset circle z can fully protect x e , that is, the target preset circle z is successfully selected;

[0160] And the target preset circle z is x e Protection resources provided

[0161] The target preset circle z is x e Idle protection resources provided

[0162] Update the available idle protection resources on the currently selected link

[0163] Among them, if x e >y e, indicating that the protection resources provided by the current target preset circle z cannot fully protect x e , can only provide y e of conservation resources;

[0164] Then the target preset circle z is x e The protection resources provided are

[0165] The target preset circle z is x e The idle protection resources provided are

[0166] Update the available idle protection resources on the currently selected link to

[0167] At this time, reselect other target preset circles z in the candidate preset circle set Z to provide (x e -y e ) until x is met e <y e , successfully select the target preset circle z;

[0168] 4.3.4. If it is a cross-link, With y e Compare the sizes and select the target preset circle z, specifically:

[0169] like Indicates that the current target preset circle z protection resources can fully protect x e , that is, the target preset circle z is successfully selected;

[0170] And the target preset circle z is x e Protection resources provided

[0171] The target preset circle z is x′ e The idle protection resources provided are

[0172] Updates the total protection resources available on the currently selected link

[0173] Among them, if Indicates that the current target preset circle z protection resources cannot fully protect x e , can only provide 2y e of conservation resources;

[0174] Then the target preset circle z is x e The protection resources provided are

[0175] The target preset circle z is x eThe provided idle protection resources are

[0176] Update the total available protection resources on the currently selected link to

[0177] At this time, reselect another target preset loop z in the candidate preset loop set Z to provide (x e -2y e ) of protection resources until it meets Successfully select the target preset loop z;

[0178] For example: in Figure 3 , assume y e ≤|F| = 50;

[0179] Select link e4, the total service bandwidth that needs to be protected is x 4 = 25 > 0. The target preset loops that can provide protection for e4 are z1, z2, z3. Then compare the number of links on the target preset loops z1, z2, z3;

[0180] Among them, the links on the preset loop z1 include e1, e2, e3, e5, e7, e8, with a total of 6;

[0181] The links on the preset loop z2 include e1, e4, e5, e6, with a total of 4;

[0182] The links on the preset loop z3 include e2, e3, e4, with a total of 3;

[0183] Obtain the minimum available protection resource among all the links on the current preset loop z3 as y = min{y 2 , y 3 , y 4} = 50;

[0184] Then, link e4 is a link on the preset loop z3. Further, compare x 4 = 25 with y = 50, and find that x e < y, indicating that the current protection resources can fully protect x 4 , then the protection resources provided by the preset loop z3 for x 4 are and the idle protection resources provided by the preset loop z3 for x 4 are And update the available idle protection resources of the links e2, e3, e4 on the preset loop z3

[0185] Next, select link e1 in turn: the total service bandwidth that needs to be protected is x 1= 15, the target preset loop set Z * is a non-empty set, containing the preset loop z3, but it cannot provide protection resources for the link e1. Then, other preset loops need to be selected from the candidate preset loop set Z as the target preset loops. The preset loops that provide protection for the link e1 are preset loops z1 and z2. Then, compare the number of links on the loops of preset loops z1 and z2;

[0186] Among them, the links on the loop of preset loop z1 include e1, e2, e3, e5, e7, e8, and the total number is 6;

[0187] The links on the loop of preset loop z2 include e1, e4, e5, e6, and the total number is 4;

[0188] At this time, in descending order according to the number of links on the loop of the preset loop, the descending order result is preset loops z2 and z1,

[0189] Calculate that the smallest available free protection resource among all the links on the loop of preset loop z2 is y = min{y 1 , y 4 , y 5 , y 6} = 25, and the link e1 is on the loop of preset loop z2;

[0190] Furthermore, compare x 1 = 15 with y = 25, and find that x 1 < y, indicating that the current protection resources can fully protect x 1 , then the protection resources provided by preset loop z2 for e1 and the free protection resources provided by preset loop z2 for x 1 Update the available free protection resources of the links e1, e4, e5, e6 on the loop of preset loop z2 At this time, preset loop z2 can be selected as the target preset loop;

[0191] Subsequently, select the link e2 in turn. The total bandwidth of the service it needs to protect is x 2 = 15. Since the preset loop set Z * is a non-empty set, which contains preset loops z3 and z2, and preset loop z3 can provide protection resources for the link e2;

[0192] At this time, compare x 2 with the protection resources that preset loop z3 can provide The free protection resources already allocated for preset loop z3 are 25, and the link e2 is on the loop of preset loop z3:

[0193] Then indicates that preset loop z3 can provide for x2 Provide sufficient protection resources and update x 2 =x 2 -x 2 =0;

[0194] Then, link e3 is selected in turn, and the total bandwidth of the service to be protected is x 3 =5, due to the preset circle set Z * is a non-empty set, including pre-set circles z3 and z2. Pre-set circle z3 can provide protection resources for link e3:

[0195] At this time, compare x 3 The size of the protection resources that the preset circle z3 can provide The idle protection resources allocated to the preset circle z3 are 25, and the link e3 is the upper link of the preset circle z3:

[0196] but Indicates that the preset circle z3 can be x 3 Provide sufficient protection resources and update x 3 =x 3 -x 3 =0;

[0197] At this time, the preset circle z3 can be selected as the target preset circle;

[0198] 4.4. All selected target preset circles z are organized into a set to obtain the target preset circle set Z. * ;

[0199] like Figure 5 As shown, the target preset circles z3 and z2 required to protect all services r of all fiber cores c on all links e are obtained, and the idle protection resources of the target preset circle z3 are 25, and the idle protection resources of the target preset circle z2 are 15;

[0200] In this step, a target candidate circle that can first provide protection for a link with a larger total service bandwidth is selected from the candidate preset circle set according to the total service bandwidth on the link. According to the protection characteristics of the preset circle, the selected target preset circle can also provide protection for other links with a smaller total service bandwidth (as long as the link is an on-circle link or a cross-link link of the target preset circle), thereby improving the protection efficiency of the target preset circle.

[0201] In the process of selecting the target preset circle, the number of links on the circle is fully considered. The fewer the number of links on the circle, the fewer the allocated idle protection resources of all the links on the circle of the target preset circle, and the fewer the total allocated idle protection resources in the space-division multiplexing optical network, so that the selected target preset circle protection can not only protect the links on the circle, but also protect the cross-links, and the protection efficiency is high;

[0202] At the same time, when selecting the target preset circle, the idle protection resource utilization rate of the target preset circle is further improved by sorting the total bandwidth of the services in all the fiber cores of all the services on the link.

[0203] In summary, the present invention generates a candidate preset circle set based on the total service bandwidth of the link in the space-division multiplexing optical network, the available idle protection resources, and the optical network topology, and determines the protection resources provided by the candidate preset circles. The candidate preset circles generated by the selection method are small in number, high in quality, and low in algorithm complexity. Then, all target preset circles are selected from the candidate preset circle set in combination with the total service bandwidth of each selected link, and finally a target preset circle set is obtained, which can not only protect the link on the circle, but also protect the cross-link, and can also provide protection for other links with smaller total service bandwidth, that is, the target preset circle set Z. * It can efficiently allocate protection resources to the space-division multiplexing optical network, with high utilization of protection resources, which can meet the protection requirements of all business requests and has high protection efficiency. At the same time, because protection resources have been configured for the protected loop links and cross-links, the protection time is shorter during fault recovery.

[0204] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for allocating protection resources in a space-division multiplexing optical network based on a preset circle, characterized in that: The following steps are involved: Step 1, obtaining the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network; Step 2: Set y e It is the idle protection resource available on each link in the space-division multiplexing optical network; Step 3: Generate a candidate preset circle set based on the total service bandwidth of the link, available idle protection resources, and optical network topology, and determine the protection resources provided by the candidate preset circle set; Step 4: According to the protection resources provided by the candidate preset circle set, the target preset circle is determined based on the total service bandwidth.

2. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 1, characterized in that: In step 1, the total service bandwidth of service requests in all fiber cores on each link in the space-division multiplexing optical network is obtained. The specific steps are as follows: 1.

1. Let G(V,E,C) be a space-division multiplexing optical network, and R be the set of all service requests in G; Where V is the set of nodes in the network topology; E is a set of directed links; C is the core collection; 1.2, set is the bandwidth of r in the cth fiber core on link e; Among them, e∈E, is the e-th link in G, c∈C, is the cth fiber core in G; 1.3, the calculation formula for the total service bandwidth of service requests in all fiber cores on each link is as follows: Among them, r∈R is the rth service request in G.

3. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 1, characterized in that: In step 2, Among them, the idle protection resource set of each link in the space-division multiplexing optical network is F, And f∈F, is the fth spectrum resource on each link, |F| is the maximum idle protection resource on each link; Among them, the available idle protection resources y on each link e Less than the maximum idle protection resource |F| on each link, that is: y e ≤|F|。 4. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 1, characterized in that: In step 3, according to the total service bandwidth of the link, the available idle protection resources, and the optical network topology, a candidate preset circle set is generated and the protection resources provided by it are determined. The specific steps are as follows: 3.

1. Arrange all links in the space-division multiplexing optical network in descending order according to the size of their total service bandwidth; 3.

2. In a link, select any node v at both ends of the link in descending order and perform depth-first search to obtain all possible set circles Q whose starting and ending points are both v and whose path length is greater than 3, and sort them in ascending order according to the path length of the set circles Q; Among them, v∈V is a node in the network topology; 3.

3. Select the single circle q in ascending order in turn. If the idle protection resources of the single circle q can provide protection for the link, select it as the candidate preset circle; Among them, q∈Q is a circle in the set circle Q; 3.

4. Repeat steps 3.2-3.3 for the remaining links, and organize the selected candidate preset circles in a unified manner to generate a candidate preset circle set Z; 3.

5. Based on the candidate preset circle set Z, determine the protection resources provided by it.

5. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 4, characterized in that: In step 3.5, based on the candidate preset circle set Z, the protection resources provided by it are determined, specifically: When the candidate preset circle set Z is determined, the protection resources it provides are all circle links and all cross links; The services that can be protected by the candidate preset circle set Z include: all circle uplinks constituting the candidate preset circle set Z and the cross-links formed by all nodes of the candidate preset circle set Z.

6. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 1, characterized in that: In step 4, according to the protection resources provided by the candidate preset circle set and based on the total service bandwidth, the target preset circle is determined. The specific steps are as follows: 4.

1. Total bandwidth x of services on all links e Sort in descending order, and select each link in turn according to the sorting; 4.

2. Let the target preset circle set be Z*. If Z* is not empty, then select the service total bandwidth x of the selected link in Z*. e Provide protection for the preset target circle z and update the total service bandwidth of link e to be protected to x e ; 4.

3. If the total service bandwidth of the selected link is x e > 0, the candidate preset circle set Z is selected in descending order of the number of links on its own circle, and the total service bandwidth x of the selected link is selected in turn. e Provides a target preset circle z for protecting resources; 4.

4. All selected target preset circles z are organized into a set to obtain the target preset circle set Z. * .

7. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 6, characterized in that: In step 4.2, let the target preset circle set be Z*. If Z* is not empty, select the service total bandwidth x of the selected link in Z*. e Provide protection for the preset target circle z and update the total service bandwidth of link e to be protected to x e , specifically: Assume the target preset circle z is the total service bandwidth x of the selected link e The protection resources provided are at this time: like This means that the target preset circle z can be x e Provide sufficient protection resources to update x e =0; like This means that the target preset circle z cannot be x e Provide adequate protection resources, update Wherein, Z*∈Z, indicates that the target preset circle set Z* is selected from the candidate preset circle set Z, and z∈Z* is an element of Z*.

8. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 6, characterized in that: In step 4.3, if the total service bandwidth x of the selected link e > 0, the candidate preset circle set Z is selected in descending order of the number of links on its own circle, and the total service bandwidth x of the selected link is selected in turn. e Provide a target preset circle z for protecting resources. The specific steps are: 4.3.

1. The candidate preset circle set Z is sorted in descending order according to the number of links in its own circle. Let the total service bandwidth x of the links selected by each target preset circle z be e The protection resources provided are Idle protection resources are 4.3.

2. Get the total service bandwidth x of the selected link e , confirm that the selected link is a link on the target preset circle z, or a cross-link; 4.3.

3. If it is a circle link, x e With y e Compare the sizes and select the target preset circle z; 4.3.

4. If it is a cross-link, With y e Compare the sizes and select the target preset circle z.

9. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 8, characterized in that: In step 4.3.3, if it is a circle link, x e With y e Compare the sizes and select the target preset circle z, specifically: If x e <y e , indicating that the protection resources provided by the current target preset circle z can fully protect x e , that is, the target preset circle z is successfully selected; And the target preset circle z is x e Protection resources provided The target preset circle z is x e Idle protection resources provided Update the available idle protection resources on the currently selected link Among them, if x e >y e , indicating that the protection resources provided by the current target preset circle z cannot fully protect x e , can only provide y e of conservation resources; Then the target preset circle z is x e The protection resources provided are The target preset circle z is x e The idle protection resources provided are Update the available idle protection resources on the currently selected link to Reselect other target preset circles z in the candidate preset circle set Z to provide (x e -y e ) until x is met e <y e , successfully selected the target preset circle z.

10. The method for allocating protection resources in a space-division multiplexing optical network based on a preset circle according to claim 8, characterized in that: In step 4.3.4, if it is a crossover link, With y e Compare the sizes and select the target preset circle z, specifically: Among them, if Indicates that the current target preset circle z protection resources can fully protect x e , that is, the target preset circle z is successfully selected; And the target preset circle z is x e Protection resources provided And the target preset circle z is x′ e The idle protection resources provided are Updates the total protection resources available on the currently selected link Among them, if Indicates that the current target preset circle z protection resources cannot fully protect x e , can only provide 2y e of conservation resources; Then the target preset circle z is x e The protection resources provided are The target preset circle z is x e The idle protection resources provided are Update the total available protection resources on the currently selected link to Reselect other target preset circles z in the candidate preset circle set Z to provide (x e -2y e ) until the protection resource is met The target preset circle z is successfully selected.

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