Redundant path planning method and system of real-time network and electronic equipment

Abstract

The invention belongs to the technical field of communication, and relates to a redundant path planning method and system for a real-time network and electronic equipment, and the method comprises the steps: obtaining a real-time network structure diagram, and obtaining a redundant path recursion tree through calculation according to the real-time network structure diagram; selecting a corresponding redundant path in the redundant path recursion tree according to a network requirement; and for the redundant paths, counting the load condition of the currently planned strong real-time data of the link corresponding to each redundant path by adopting an incremental calculation mode, and selecting the redundant path with the minimum link load and the balanced redundant link load as the planned redundant path. By planning the transmission path of the strong real-time data in the network structure, the corresponding redundant path can be found under different network topologies, so that the flexibility can be improved, various changes of the network topologies can be met, and the method has positive significance in improving the reliability and flexibility of the time-triggered network.

Description

Technical Field

[0001] The invention belongs to the technical field of communications and relates to a redundant path planning method, system and electronic equipment for a real-time network. Background Art

[0002] Time-triggered communication networks often use data redundant transmission to ensure the reliability of strong real-time data. Traditional PRP (Parallel Redundancy Protocol) and HSR (High-availabilty Seamless Reduncy) redundancy strategies replicate data through multiple independent subnets and transmit them in parallel in each subnet. Although they ensure seamless switching of data when a single point failure occurs, these two redundancy methods are extremely costly, inflexible, and have high requirements for network topology. In the case of complex network topology and working environment, they cannot guarantee the reliability of network transmission.

[0003] Currently, IEEE802.1CB provides a frame replication and elimination (FRER) technology, which improves the reliability of network transmission by numbering key data and replicating and eliminating data frames. However, the strong real-time data in the time-triggered network has extremely high requirements for delay and jitter, and the transmission path needs to be strictly restricted. Therefore, when using the FRER mechanism for redundant transmission, if the redundant path is not restricted, the real-time performance of the strong real-time data cannot be guaranteed. Summary of the invention

[0004] The purpose of the present invention is to provide a redundant path planning method, system and electronic device for a real-time network to solve the technical problem in the prior art that the real-time performance of strong real-time data cannot be guaranteed when the FRER mechanism is used for redundant transmission.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present application discloses a redundant path planning method for a real-time network, comprising:

[0007] Obtain a real-time network structure diagram, and calculate a redundant path recursive tree according to the real-time network structure diagram;

[0008] According to network requirements, select the corresponding redundant path in the redundant path recursive tree;

[0009] For redundant paths, an incremental calculation method is used to count the load of the currently planned strong real-time data of the link corresponding to each redundant path, and the redundant path with the smallest link load and redundant link load balance is selected as the planned redundant path.

[0010] Preferably, the obtaining of the real-time network structure diagram specifically includes: obtaining strong real-time data and real-time network topology; numbering each end node and switching node in the real-time network topology, taking two nodes as a group, representing all links in the real-time network, and obtaining a real-time network structure diagram, in which the source node and destination node corresponding to the strong real-time data are clearly defined.

[0011] Preferably, the step of calculating the redundant path recursive tree according to the real-time network structure diagram specifically includes:

[0012] Use Dijkstra algorithm to calculate the shortest path from the destination node to each node, and obtain a result set of predecessor nodes of the shortest path;

[0013] The result set is stored in a two-dimensional array, and the two-dimensional array is processed using a depth-first search algorithm to obtain a redundant recursive tree.

[0014] Preferably, the network requirements include the quantity, cycle, size of strong real-time data of the network and the requirements of the network for reliability.

[0015] Preferably, the redundant link load balancing is specifically: taking the minimum value of the variance between the load of each link and the average value of the load of all links to ensure the redundant link load balancing; the expression is as follows:

[0016]

[0017] In the formula, B i represents the load size of the i-th link, Indicates the average load of all links.

[0018] In a second aspect, the present application discloses a redundant path planning system for a real-time network, comprising:

[0019] A calculation unit, used for obtaining a network structure diagram in real time, and calculating a redundant path recursive tree according to the real-time network structure diagram;

[0020] A selection unit, used for selecting a corresponding redundant path in the redundant path recursive tree according to network requirements;

[0021] The planning unit is used to calculate the load of the currently planned strong real-time data of the link corresponding to each redundant path by incremental calculation for the redundant path, and select the redundant path with the smallest link load and balanced redundant link load as the planned redundant path.

[0022] Preferably, the computing unit obtains a real-time network structure diagram, specifically including: obtaining strong real-time data and real-time network topology; numbering each end node and switching node in the real-time network topology, taking two nodes as a group, representing all links in the network, and obtaining a real-time network structure diagram, in which the source node and destination node corresponding to the strong real-time data are clearly defined.

[0023] Preferably, the step of calculating the redundant path recursive tree according to the real-time network structure diagram specifically includes:

[0024] Use Dijkstra algorithm to calculate the shortest path from the destination node to each node, and obtain a result set of predecessor nodes of the shortest path;

[0025] The result set is stored in a two-dimensional array, and the two-dimensional array is processed using a depth-first search algorithm to obtain a redundant recursive tree.

[0026] In a third aspect, the present application discloses an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above-mentioned redundant path planning methods for a real-time network when executing the computer program.

[0027] In a fourth aspect, the present application discloses a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the redundant path planning method for a real-time network described in any one of the above items are implemented.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1) The present invention can generate redundant paths for each strong real-time data under various network topologies according to network conditions and requirements, thereby improving the flexibility of the redundancy strategy.

[0030] 2) When generating redundant paths, the present invention can generate redundant paths with balanced network link loads based on the current load conditions of each link, thereby avoiding the situation where the link load is too large.

[0031] 3) By planning the transmission path of strong real-time data in the network structure, it is possible to find the corresponding redundant path under different network topologies, thereby improving its flexibility and meeting various changes in network topology, which has a positive significance for improving the reliability and flexibility of the time-triggered network. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 is a flow chart of the method of the present invention;

[0034] Figure 2 A schematic diagram of a network topology structure according to an embodiment of the present invention;

[0035] Figure 3 This is a recursive tree diagram of redundant paths according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0039] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0040] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0041] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0043] See also Figure 1 , the present application discloses a redundant path planning method for a real-time network, comprising:

[0044] S1: Obtain a network structure diagram, and calculate a redundant path recursive tree according to the network structure diagram;

[0045] S2: Select a corresponding redundant path in the redundant path recursive tree according to network requirements;

[0046] S3: For redundant paths, an incremental calculation method is used to count the load of the currently planned strong real-time data of the link corresponding to each redundant path, and a redundant path with the smallest link load and redundant link load balance is selected as the planned redundant path.

[0047] By planning the transmission path of strong real-time data in the network structure, it is possible to find the corresponding redundant path under different network topologies, thereby improving its flexibility and meeting various changes in network topology, which has positive significance for improving the reliability and flexibility of the time-triggered network.

[0048] Strong real-time data means that data has a high degree of real-time performance during the generation, transmission and processing process, can quickly reflect the current status or situation, and allow users to access and analyze the data immediately when needed.

[0049] In some embodiments, the obtaining of the network structure diagram specifically includes: numbering each end node and switching node in the network topology, taking two nodes as a group, representing all links in the network, and obtaining a network structure diagram, in which the source node and destination node corresponding to the strong real-time data are clearly identified in the real-time network structure diagram.

[0050] In some embodiments, the step of calculating the redundant path recursive tree according to the network structure diagram specifically includes:

[0051] Use Dijkstra algorithm to calculate the shortest path from the destination node to each node, and obtain a result set of predecessor nodes of the shortest path;

[0052] The result set is stored in a two-dimensional array, and the two-dimensional array is processed using a depth-first search algorithm to obtain a redundant recursive tree.

[0053] In some embodiments, the network requirements include the quantity, period, size of strong real-time data of the network and the requirements of the network for reliability.

[0054] In some embodiments, the redundant link load balancing is specifically to take the minimum value of the variance between the load of each link and the average value of the load of all links to ensure the redundant link load balancing; the expression is as follows:

[0055]

[0056] In the formula, B i represents the load size of the i-th link, Indicates the average load of all links.

[0057] In some embodiments, a redundant path planning method for a real-time network includes:

[0058] (1) Generate redundant path mechanism

[0059] Each end node and switching node in the network topology is numbered, and two nodes can be grouped together to represent all links in the network, thereby representing the structure of the entire network. In addition, strong real-time data has extremely high requirements for real-time and reliability. Strong real-time data in the network is generally periodic control information data. Therefore, each strong real-time data is numbered, and the source node and destination node of each strong real-time data need to be known.

[0060] According to the entire network structure diagram expressed above, all redundant paths between any two end nodes are calculated. First, the Dijkstra algorithm is used to obtain the set of predecessor nodes of the shortest path from the destination node to each node, and the result is stored in a two-dimensional array. Then, a depth-first search algorithm is performed on the array to obtain a redundant recursive tree, which contains all the shortest symmetric paths from the source node to the destination node (with the smallest and identical number of hops), that is, all redundant paths from the source node to the destination node are generated. Similarly, according to the source nodes and destination nodes of the remaining strong real-time data, the redundant path recursive tree corresponding to all strong real-time data can be calculated.

[0061] (2) Redundant Path Selection Mechanism

[0062] The fewer the overlapping links between the redundant paths, the higher the reliability of the strong real-time data in the network. Therefore, when selecting redundant paths, the overlapping links between the paths should be minimized. At the same time, the number of redundant path plans should be planned according to the actual situation of the entire network. When the number of redundant paths is too small, the reliability of the network cannot be guaranteed. However, the reliability of the network does not increase infinitely with the increase in the number of redundant paths. When all links on the shortest path have been planned, the reliability reaches the maximum value. At the same time, when the number of redundant path plans is too large, it will also increase the difficulty of planning the sending and receiving time points of the strong real-time data on the switching node. Therefore, the number of each strong real-time data redundant path should be planned according to the number, cycle, size of the strong real-time data of the entire network and the network's requirements for reliability.

[0063] (3) Redundant Link Load Balancing Mechanism

[0064] Add load parameters for each link and count the load of the currently planned strong real-time data for each link. Use incremental calculation to plan each strong real-time data in turn. When a redundant path for strong real-time data is planned, calculate the link load it needs to occupy based on the cycle and size of the strong real-time data, and add it to the load parameters of all links through which the data passes. The link load parameter can also be used as one of the indicators for redundant path planning. When the link load is too large, the probability of network communication problems will also increase. Therefore, when planning redundant paths, try to avoid links with excessive loads and choose redundant paths with smaller link loads, so as to achieve the effect of balancing the load of the entire network link.

[0065]

[0066] As shown in formula 1, B i represents the load size of the i-th link, It represents the average load of all links, that is, the minimum value of the variance between the load of each link and the average value of the load of all links is taken to ensure the load balancing of redundant links.

[0067] [Example]

[0068] According to the content of the present invention, a detailed implementation scheme is designed to construct a network topology of 11 nodes, which includes end nodes A, B, C, D, E, switching nodes 1, 2, 3, 4, 5, 6, and the interconnection relationship between the nodes is as follows: Figure 2 shown.

[0069] Assume that there are 8 strong real-time data at present, and their information is shown in Table 1:

[0070] Table 1 Attribute parameters of strong real-time data

[0071]

[0072]

[0073] Redundant path planning is performed using incremental calculation, starting from the first strong real-time data. The process of redundant path planning is as follows:

[0074] (1) First, use the Dijkstra algorithm to obtain the set of predecessor nodes of the shortest path from the destination node B to each node, and create a two-dimensional array pre[7]. The result is stored in a two-dimensional array. The obtained two-dimensional array is as follows:

[0075] pre{B}={};

[0076] pre{5}={B}; pre{6}={B};

[0077] pre{3}={5,6}; pre{4}={5,6};

[0078] pre{1}={3, 4}; pre{2}={3, 4};

[0079] pre{A}={1,2}.

[0080] Then perform a depth-first search algorithm on the two-dimensional array to obtain a recursive tree, such as Figure 3 As shown, the recursive tree contains all the shortest symmetric paths (with the smallest number of hops and the same number of hops) from the source node A to the destination node B;

[0081] (2) According to network requirements, Figure 3 Select the corresponding redundant path in the redundant path recursive tree. When only two redundant paths are selected, different nodes are selected at each level of the recursive tree, and a total of four groups of two unrelated paths can be obtained, as follows:

[0082] a. b.

[0083] c. d.

[0084] The above four groups of redundant paths can ensure that the data transmission will not be affected when any link fails. When two links fail, the data transmission may be affected. At this time, more redundant paths can be selected to ensure the reliability of the data. The reliability results of the selected redundant paths under different link failures are shown in Table 2:

[0085] Table 2 Network reliability statistics

[0086]

[0087] As shown in Table 2, the reliability of the network increases with the increase in the number of redundant paths. However, in this topology, when the number of redundant paths selected is greater than 4, the network reliability guaranteed by redundancy reaches the maximum value. This is because, in this network topology, when the number of redundant paths exceeds 4, the redundant paths already contain all the links in the shortest path from source node A to destination node B. When adding redundant paths, it is just to rearrange the selected links into a new path. Therefore, adding new redundant paths can no longer improve its reliability. It can be seen from this that the number of redundant paths for each strong real-time data needs to be determined based on the network topology and the information of strong real-time data in the network.

[0088] (3) Assume that the first strong real-time data selects two redundant paths, namely path 1: A-1-3-5-B, path 2: A-2-4-6-B. The communication cycle of this data is 1ms, the message length is 100Bytes, and its bandwidth is 100KBps, that is, the load occupied is 100KBps. This load is added to the load parameters of each link of its redundant path. According to the planning method of the first strong real-time data, plan the remaining strong real-time data in turn. According to the current load of each link, select the redundant path with the smaller current link load, and add its occupied bandwidth to the load parameters of the corresponding redundant link.

[0089] It can be seen that the redundant path planning method solves the problem that the FRER redundancy mechanism cannot guarantee the link symmetry, and is more reliable and flexible than the traditional method of redundant node backup, and is more cost-effective. At the same time, in response to the extreme situations that may occur in the link load, each link load parameter is added, and a load balancing strategy is formulated to avoid delay bottleneck problems, further improving its reliability.

[0090] The present application also discloses a redundant path planning system for a real-time network, comprising:

[0091] A calculation unit, used for obtaining a network structure diagram in real time, and calculating a redundant path recursive tree according to the real-time network structure diagram;

[0092] A selection unit, used for selecting a corresponding redundant path in the redundant path recursive tree according to network requirements;

[0093] The planning unit is used to calculate the load of the currently planned strong real-time data of the link corresponding to each redundant path by incremental calculation for the redundant path, and select a redundant path with a small link load and a balanced redundant link load as the planned redundant path.

[0094] In some embodiments, the computing unit obtains a real-time network structure diagram, specifically including: obtaining strong real-time data and real-time network topology; numbering each end node and switching node in the real-time network topology, taking two nodes as a group, representing all links in the network, and obtaining a real-time network structure diagram. In the real-time network structure diagram, for the strong real-time data, the corresponding source node and destination node are clearly identified.

[0095] In some embodiments, the computing unit calculates a redundant path recursive tree according to the real-time network structure diagram, specifically including:

[0096] Use Dijkstra algorithm to obtain the result set of predecessor nodes of the shortest path from the destination node to each node;

[0097] The result set is stored in a two-dimensional array, and a depth-first search algorithm is performed on the two-dimensional array to obtain redundant recursion.

[0098] The present application discloses an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the redundant path planning method for a real-time network described in any one of the above items are implemented.

[0099] The present application discloses a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above-mentioned redundant path planning methods for a real-time network are implemented.

[0100] According to the above scheme, the matrix can perfectly express the relationship between each node and link, and the basic data unit of Matlab is the matrix, which can perform matrix operations, draw functions and data, implement algorithms, and connect programs of other programming languages, etc. Therefore, Matlab is used to describe the network topology, each node information, and each strong real-time data information, and the corresponding number of redundant paths can be generated according to the demand for the number of redundant paths; the generated redundant paths are used in the key technology research project of time-sensitive networks to carry out network testing. The test results show that the present invention has good feasibility, and the redundant paths after planning can better ensure the reliability and real-time performance of the network, and the functions meet expectations.

[0101] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0102] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0103] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0104] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A redundant path planning method for a real-time network, characterized in that: include: Obtain a real-time network structure diagram, and calculate a redundant path recursive tree according to the real-time network structure diagram; According to network requirements, select the corresponding redundant path in the redundant path recursive tree; For redundant paths, an incremental calculation method is used to count the load of the currently planned strong real-time data of the link corresponding to each redundant path, and the redundant path with the smallest link load and redundant link load balance is selected as the planned redundant path.

2. A redundant path planning method for a real-time network according to claim 1, characterized in that: The obtaining of the real-time network structure diagram specifically includes: obtaining strong real-time data and real-time network topology; numbering each end node and switching node in the real-time network topology, taking two nodes as a group, representing all links in the real-time network, and obtaining a real-time network structure diagram, in which the source node and destination node corresponding to the strong real-time data are clearly defined.

3. A redundant path planning method for a real-time network according to claim 2, characterized in that: The method of calculating the redundant path recursive tree according to the real-time network structure diagram specifically includes: Use Dijkstra algorithm to calculate the shortest path from the destination node to each node, and obtain a result set of predecessor nodes of the shortest path; The result set is stored in a two-dimensional array, and the two-dimensional array is processed using a depth-first search algorithm to obtain a redundant recursive tree.

4. A redundant path planning method for a real-time network according to claim 1, characterized in that: The network requirements include the quantity, cycle, size of strong real-time data of the network and the requirements of the network for reliability.

5. The redundant path planning method for a real-time network according to claim 1, characterized in that: The redundant link load balancing is specifically: taking the minimum value of the variance between the load of each link and the average value of the load of all links to ensure the redundant link load balancing; the expression is as follows: In the formula, B i represents the load size of the i-th link, Indicates the average load of all links.

6. A redundant path planning system for a real-time network, characterized in that: include: A calculation unit, used for obtaining a network structure diagram in real time, and calculating a redundant path recursive tree according to the real-time network structure diagram; A selection unit, used for selecting a corresponding redundant path in the redundant path recursive tree according to network requirements; The planning unit is used to calculate the load of the currently planned strong real-time data of the link corresponding to each redundant path by incremental calculation for the redundant path, and select the redundant path with the smallest link load and balanced redundant link load as the planned redundant path.

7. A redundant path planning system for a real-time network according to claim 6, characterized in that: The real-time network structure diagram is obtained in the computing unit, specifically including: obtaining strong real-time data and real-time network topology; numbering each end node and switching node in the real-time network topology, taking two nodes as a group, representing all links in the network, and obtaining a real-time network structure diagram, in which the source node and destination node corresponding to the strong real-time data are clearly defined.

8. A redundant path planning system for a real-time network according to claim 7, characterized in that: The method of calculating the redundant path recursive tree according to the real-time network structure diagram specifically includes: Use Dijkstra algorithm to calculate the shortest path from the destination node to each node, and obtain a result set of predecessor nodes of the shortest path; The result set is stored in a two-dimensional array, and the two-dimensional array is processed using a depth-first search algorithm to obtain a redundant recursive tree.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the redundant path planning method for a real-time network as described in any one of claims 1 to 5 when executing the computer program.

10. A computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the redundant path planning method for a real-time network according to any one of claims 1 to 5.

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