JP2022132907A - Communication method, communication system, and communication device - Google Patents

Abstract

To provide a communication method, a communication system, and a communication device that maintain a requested communication performance even if devices connected to a network are changed.SOLUTION: In a control system 1, a communication method in a network conforming to TSN (time-sensitive networking) includes the steps of: acquiring communication setting information defining frames exchanged on the network and ability information defining information on a performance related to the TSN of devices connected to the network; calculating TSN settings including communication schedules of frames in the devices on the basis of network configuration information defining one or more connection forms of the devices that may occur in the network, the communication setting information, and the ability information so that necessary frame transfer can be achieved in any connection form included in the network configuration information; and providing the TSN settings to the devices connected to the network.SELECTED DRAWING: Figure 1

Description

The present technology relates to a communication method, a communication system, and a communication device.

Efforts are underway to expand standard networks (for example, Ethernet (registered trademark)) used in general information networks so that they can also be used in networks in the industrial field. More specifically, IEEE (Institute of Electrical and Electronic Engineers) 802.1 TSN (Time Sensitive Networking) (hereinafter referred to as Time Sensitive Networking), which is based on Ethernet (registered trademark) and improved so that the network behaves deterministically. Also referred to as the "TSN standard"). According to the TSN standard, for example, real-time communication can be realized more easily using general-purpose hardware such as Ethernet (registered trademark).

For example, Patent Document 1 (European Patent No. 03357218) discloses an industrial network using a network conforming to the TSN standard.

EP 03357218

At the production site, the devices and jigs used are often changed in accordance with changes in the types of products to be produced and in the production process. Such a change is also called a changeover. Along with such a setup change, the devices connected to the industrial network are also changed.

No consideration is given to a mechanism for maintaining the required communication performance even when the connected device is changed.

This technology provides a mechanism for maintaining required communication performance even when devices connected to the network are changed.

According to one embodiment of the present technology, a communication method in a TSN compliant network is provided. The communication method includes steps of obtaining communication setting information defining frames exchanged on a network and capability information defining performance information related to TSN of a device connected to the network; calculating a TSN setting including a communication schedule for frames in each device based on network configuration information defining one or more configurations, communication setting information, and capability information; and providing to. Calculating the TSN settings includes calculating the TSN settings so as to achieve the necessary frame forwarding for any of the topologies included in the network configuration information.

According to this configuration, for example, when it is planned that the network configuration (connection configuration of devices) is changed due to a setup change, etc., a network that defines one or more connection configurations of devices that can occur in the network. By calculating the TSN setting using the configuration information, the required communication performance can be maintained in any network configuration.

The step of calculating the TSN setting may be initiated when a predetermined condition is met. According to this configuration, a network according to TSN can be managed mainly by a management entity such as a network controller.

Computing the TSN settings may be initiated in response to a request from a network-connected device. According to this configuration, it is possible to calculate the optimum TSN setting when a device is newly connected to the network.

The step of calculating the TSN setting determines whether the setting information calculated for one topology included in the network configuration information can achieve necessary frame forwarding in another topology included in the network configuration information. may include steps. According to this configuration, it is possible to calculate a TSN setting that can maintain the required communication performance for any of the device connection modes defined in the network configuration information.

The communication method includes, when a connection topology different from the connection topology of the device defined in the network configuration information is detected, recalculating the TSN setting so as to realize necessary frame transfer in the different connection topology. It may contain further. According to this configuration, an appropriate TSN setting can be calculated even for a connection type that was not considered in the original TSN setting calculation.

The communication method may further comprise, upon determining that the recalculated TSN settings should be reflected, signaling the need for such reflection. This configuration gives the user an opportunity to consider the effects in the network when there is a need to reflect new TSN settings.

The communication method may further comprise providing the recalculated TSN setting to the network-connected device in response to the explicit acknowledgment. According to this configuration, the TSN setting is reflected only when the user or the like explicitly approves it, so it is possible to reduce the possibility of unintended problems occurring in the network.

The communication method comprises the steps of each device collecting neighboring node information, generating a topology of the network based on the neighboring node information collected by each device, and updating network configuration information based on the generated topology. and a step.

According to another embodiment of the present technology, a communication system is provided that includes a TSN compliant network. A communication system includes a network controller and one or more devices connected to a network. The network controller includes means for acquiring communication setting information defining frames exchanged on the network, capability information defining performance information related to TSN of one or more devices, and possible connection types of devices on the network. means for calculating a TSN setting including a communication schedule for frames in each device based on network configuration information defining one or more of, communication setting information, and capability information; and providing the TSN setting to one or more devices and means to The means for calculating the TSN settings calculates the TSN settings so as to achieve the required frame forwarding in any of the topologies included in the network configuration information.

According to yet another embodiment of the present technology, a network controller is provided for configuring a TSN compliant network. The network controller includes means for acquiring communication setting information defining frames exchanged on the network and capability information defining performance information related to the TSN of devices connected to the network, and connection of devices that may occur on the network. Means for calculating a TSN setting including a communication schedule of frames in each device based on network configuration information defining one or more configurations, communication setting information, and capability information; and means for providing The means for calculating the TSN settings calculates the TSN settings so as to achieve the required frame forwarding in any of the topologies included in the network configuration information.

According to the present technology, it is possible to provide a mechanism for maintaining required communication performance even when a device connected to a network is changed.

1 is a schematic diagram showing an example of the overall configuration of a control system according to an embodiment; FIG. 2 is a block diagram showing an example hardware configuration of an end device that constitutes the control system according to the present embodiment; FIG. 3 is a block diagram showing an example hardware configuration of a switch that constitutes the control system according to the present embodiment; FIG. 2 is a block diagram showing an example hardware configuration of a network controller that configures the control system according to the present embodiment; FIG. 4 is a schematic diagram showing a more detailed configuration of one port of the switch shown in FIG. 3; FIG. FIG. 4 is a diagram for explaining an example of processing related to frame transfer in the control system according to the present embodiment; FIG. FIG. 4 is a diagram for explaining an outline of processing in the control system according to the embodiment; FIG. FIG. 7 is a diagram showing a processing procedure of topology generation processing by the network controller of the control system according to the present embodiment; FIG. 4 is a diagram showing a processing procedure for detecting a topology change by a network controller of the control system according to the present embodiment; FIG. 7 is a diagram showing a processing procedure in Push mode in the control system according to the present embodiment; 4 is a diagram showing an example of communication setting information used in the control system according to the embodiment; FIG. It is a figure which shows the processing procedure in the Request mode in the control system which concerns on this Embodiment. FIG. 9 is a diagram showing another processing procedure in Request mode in the control system according to the present embodiment; FIG. 7 is a diagram showing a processing procedure in Push mode in the network controller of the control system according to the present embodiment; FIG. 4 is a diagram showing a processing procedure in Request mode in the network controller of the control system according to the present embodiment;

Embodiments of the present technology will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

<A. Application example>
First, an example of the overall configuration of the control system 1 according to this embodiment will be described. FIG. 1 is a schematic diagram showing an example of the overall configuration of a control system 1 according to this embodiment.

A control system 1 shown in FIG. 1 is an example of a communication system including a network conforming to TSN. Therefore, processing related to the network in the control system 1 corresponds to communication processing in the network according to TSN.

In this specification, unless otherwise specified, the term simply "TSN" generically refers to networks that follow TSN. Also, the term "TSN settings" encompasses the settings necessary to implement a TSN-compliant network.

As used herein, "device" encompasses any device connected to a network that conforms to TSN. A "device" may typically include end devices and switches.

A control device such as a PLC (programmable controller) is connected to the TSN of the control system 1 . A control device connected to a network corresponds to an end device, so the control device is referred to as an "end device" in the following description. However, the "end device" is not limited to the control device, and may include any device.

A control system 1 shown in FIG. 300. A network to which one or more of these devices are connected corresponds to the TSN.

End device 100-1 is connected via link 20 to switch 200-1. A link 22 is connected between the switch 200-1 and the switch 200-2. The end device 100-2 can be connected to the switch 200-2 via the link 24, and the end device 100-3 can be connected via the link 26 to the switch 200-2.

A network controller 300 is connected to the switch 200-1 via a link .

It is assumed that the end device 100-2 and the end device 100-3 are selectively connected to the switch 200-2 by a setup change. That is, the TSN shown in FIG. 1 can have a state in which end devices 100-1 and 100-2 are connected and a state in which end devices 100-1 and 100-3 are connected.

Each of the end devices 100-1, 100-2, 100-3 has a fieldbus 30 independent of the TSN. One or more field devices 40 are connected to the fieldbus 30 . One or more field devices 40 include input devices that obtain field signals and output devices or actuators that perform some action on the field according to instructions from the end device 100 .

The network controller 300 is the entity that manages frame transfers in the TSN and determines communication schedules for frame transfers by calculating resource allocation and availability. In the following, resource allocation and availability calculations by the network controller 300 are also referred to as "TSN calculations". Typically, the network controller 300 may operate according to the IEEE 802.1Qcc specification, which is a substandard of IEEE 802.1 TSN.

In TSN, an identification label given to each frame includes a stream ID, a stream destination address, and a traffic class. The network controller 300 determines a unique stream ID for each frame transferred within the TSN and determines the stream destination address and traffic class according to the transfer path of each of the stream IDs. and for each of the switches 200, provide the TSN settings. The TSN setting includes a communication schedule determined in consideration of the band for each stream.

In the control system 1 according to the present embodiment, the network controller 300 performs appropriate resource allocation and availability calculations, so that even if the device connected to the TSN is changed due to a setup change or the like, Optimal performance can be achieved for the TSN as a whole.

<B. Hardware configuration example>
Next, an example of the hardware configuration of each device included in the control system 1 will be described.

(b1: End device 100 (control device))
FIG. 2 is a block diagram showing a hardware configuration example of the end device 100 that configures the control system 1 according to this embodiment. Referring to FIG. 2, end device 100 includes processor 102 , main memory 104 , network interface 110 , storage 120 , internal bus interface 130 , fieldbus interface 132 and memory card interface 134 . Each component is electrically connected via bus 138 .

The processor 102 is composed of a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), a GPU (Graphical Processing Unit), etc., reads out various programs stored in the storage 120, develops them in the main memory 104, and executes them. By doing so, processing as a control device is realized.

The network interface 110 is in charge of exchanging data (frame transmission) via TSN. More specifically, network interface 110 includes transmission/reception control circuitry 112 , transmission circuitry 114 , and reception circuitry 116 . The transmission/reception control circuit 112 controls the transmission circuit 114 and the reception circuit 116 according to the TSN setting given in advance from the network controller 300 . The transmission circuit 114 transmits frames on the TSN according to instructions from the transmission/reception control circuit 112 . Receive circuit 116 receives incoming frames via TSN.

The storage 120 typically stores a system program 122 for realizing functions as a control device and a user program 124 that defines control logic executed by the control device.

The internal bus interface 130 exchanges data with the I/O unit 140 mounted on the end device 100 .

Fieldbus interface 132 exchanges data with field devices via fieldbus 30 .

The memory card interface 134 is configured such that a memory card 136 can be attached/detached, and data can be written to the memory card 136, and various data (user program, trace data, etc.) can be read from the memory card 136. ing.

FIG. 2 shows a configuration example in which necessary functions are provided by the processor 102 executing a program. (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), etc.). Alternatively, the main part of the end device 100 may be implemented using hardware following a general-purpose architecture (for example, an industrial personal computer based on a general-purpose personal computer). As such, the processing performed and functions provided by end device 100 may be implemented in processing circuitry including processors, ASICs, FPGAs, and the like.

(b2: switch 200)
FIG. 3 is a block diagram showing a hardware configuration example of the switch 200 that configures the control system 1 according to this embodiment. Referring to FIG. 3, switch 200 includes a transmission/reception control circuit 212 and transmission circuits 214-1, 214-2, 214-3, and 214-4 (hereinafter collectively referred to as "transmission circuits 214"). , and receiving circuits 216-1, 216-2, 216-3, and 216-4 (hereinafter also collectively referred to as “receiving circuits 216”). A set of the transmission circuit 214 and the reception circuit 216 forms one port. Note that FIG. 3 illustrates the switch 200 having four ports, but the number of ports is not particularly limited.

The transmission/reception control circuit 212 controls the transmission circuit 114 and the reception circuit 116 according to the TSN setting given in advance from the network controller 300 . More specifically, the transmit/receive control circuit 212 includes a transfer engine 218 and a queue 220 .

The transmission/reception control circuit 212 may be implemented by a processor executing firmware, or may be implemented using a hardwired circuit such as an ASIC or FPGA. Also, not only the transmission/reception control circuit 212 but also the entirety including the transmission circuit 114 and the reception circuit 116 may be implemented in a single chip. As such, the processing performed and functions provided by switch 200 may be implemented in processing circuitry including processors, ASICs, FPGAs, and the like.

(b3: network controller 300)
FIG. 4 is a block diagram showing a hardware configuration example of the network controller 300 that configures the control system 1 according to this embodiment. Referring to FIG. 4, network controller 300 includes processor 302 , main memory 304 , network interface 310 and storage 320 . Each component is electrically connected via bus 338 .

The processor 302 is composed of a CPU, an MPU, a GPU, etc., reads various programs stored in the storage 320, develops them in the main memory 304, and executes them, thereby realizing processing as a network controller.

The network interface 310 is in charge of exchanging data (frame transmission) via TSN. More specifically, network interface 310 includes transmit/receive control circuitry 312 , transmit circuitry 314 , and receive circuitry 316 .

The storage 320 typically stores an OS 322 for implementing basic processing and a network setting program 324 for implementing processing as described later.

FIG. 4 shows a configuration example in which necessary functions are provided by the processor 302 executing a program. As such, the processing performed and functions provided by network controller 300 may be implemented in processing circuitry including processors, ASICs, FPGAs, and the like.

<C. Principal Configuration for Realizing TSN>
Next, the main configuration for realizing the TSN of the control system 1 according to this embodiment will be described. That is, a configuration example of a port for transmitting and receiving frames in TSN will be described.

FIG. 5 is a schematic diagram showing a more detailed configuration of one port of switch 200 shown in FIG. With reference to FIG. 5, each port consists of a set of a transmitter circuit 214 and a receiver circuit 216 . Transfer engine 218 and queue 220 are provided between transmit circuit 214 and receive circuit 216 .

More specifically, transfer engine 218 includes distribution circuit 224 and timing control circuit 226 . Queue 220 also includes a plurality of queues 220-1 to 220-M associated with each traffic class value.

Distribution circuit 224 stores the frame in one of queues 220-1 to 220-M according to the header information of the frame received via reception circuit 216, or distributes the frame to distribution circuit 224 of another port. transfer to Also, the sorting circuit 224 performs similar determination and processing for frames received from the sorting circuit 224 of another port.

When the distribution circuit 224 receives a frame to be sent from the transmission circuit 214 of its own port, the distribution circuit 224 stores the frame in the queue 220 corresponding to the traffic class of the frame. By such processing in the distribution circuit 224, the queues 220-1 to 220-M sequentially store frames classified by traffic class.

Gates 222-1 to 222-M are provided on the output sides of the queues 220-1 to 220-M, respectively. Each of gates 222 - 1 to 222 -M (hereinafter collectively referred to as “gates 222 ”) opens and closes according to instructions from timing control circuit 226 . When the gate 222 is opened, the frame stored in the associated queue 220 is sent from the transmission circuit 214 . Timing control circuit 226 does not give open commands to a plurality of gates 222 at the same time. That is, the timing control circuit 226 sequentially opens and closes the gates 222 according to the communication schedule 228 included in the TSN settings. As a result, frames are transferred according to the communication schedule calculated in advance by TSN.

The port of the end device 100 (network interface 110) and the port of the network controller 300 (network interface 310) also have the same configuration as in FIG.

By controlling the storage of frames in the queues 220 prepared for each traffic class and the transmission of frames from the queues 220 prepared for each traffic class as described above, real-time frame transfer in the TSN can be realized. .

<D. Overview>
Next, an outline of processing in the TSN of the control system 1 according to this embodiment will be described.

FIG. 6 is a diagram for explaining an example of processing related to frame transfer in the control system 1 according to the present embodiment. As shown in FIG. 6A, it is assumed that frames are transmitted from the end device 100-1 to the end devices 100-2 and 100-3.

A switch 200-1 and a switch 200-2 are present along the route. As described with reference to FIG. 5, the end device 100 and the switch 200 realize real-time frame transfer by controlling the opening/closing timing of the gate 222 .

The opening/closing time and opening/closing timing of the gate 222 are typically calculated based on the transmission time required for frame transmission processing and the frame propagation delay time. The transmission time is calculated according to the size of the transmitted frame (frame size). Propagation delay time varies according to the length of the transfer path. Generally, the propagation delay time is a value measured when an arbitrary frame is transmitted.

FIG. 6B shows an example of the timing of the gate 222 in the network configuration shown in FIG. 6A. In the time chart shown in FIG. 6B, the upper section means the open state of the gate 222 .

After gate 222 of end device 100-1 opens, the frame is transmitted to switch 200-1. Gate 222 of switch 200-1 will open with a delay that reflects the time the frame from end device 100-1 arrives and is stored in queue 220. FIG. After gate 222 of switch 200-1 opens, the frame is transmitted to switch 200-2.

The end device 100-2 is connected to port 1 of the switch 200-2, and the end device 100-3 is connected to port 2 of the switch 200-2. For example, between the propagation delay time to the end device 100-2 connected to the port 1 of the switch 200-2 and the propagation delay time to the end device 100-3 connected to the port 2 of the switch 200-2 Suppose there is a difference. In such a case, a predetermined time difference occurs between the opening timing of the gate 222 corresponding to the port 1 of the switch 200-2 and the opening timing of the gate 222 corresponding to the port 2 of the switch 200-2. become.

FIG. 7 is a diagram for explaining an outline of processing in the control system 1 according to this embodiment. 7A shows a state in which the end device 100-2 is connected to port 1 of the switch 200-2, and FIG. 7B shows a state in which the end device 100-2 is connected to port 2 of the switch 200-2. 3 is connected.

Referring to FIG. 7(C), the opening time of the port in the state where only the end device 100-2 as shown in FIG. 7(A) is connected and the end device 100 as shown in FIG. There may be a difference in length or timing between the open time of the port with only -3 connected.

The port opening time is set so as to include the state in which both the end device 100-2 and the end device 100-3 are connected to the switch 200-2 and the state in which only one of them is connected.

For example, the network configuration may change due to a new device being connected after the network controller 300 has calculated the TSN in a state where not all devices are connected to the TSN, or due to a setup change. . In such a case, if the initial TSN calculation does not consider the changed network configuration, it will be necessary to perform the TSN calculation again.

Therefore, the control system 1 according to the present embodiment performs TSN calculation so that appropriate frame transfer can be performed in any network configuration. By performing such TSN calculation, it is possible to arbitrarily change the network configuration while operating the TSN. That is, considering the worst value among assumed network configurations, the TSN calculation is performed so as to secure the gate opening/closing time and bandwidth.

<E. Processing procedure>
Next, an example of a processing procedure in the control system 1 according to this embodiment will be described.

FIG. 8 is a diagram showing a processing procedure of topology generation processing by the network controller 300 of the control system 1 according to the present embodiment. From the topology generated by the processing procedure shown in FIG. 8, candidates for the device connection configuration included in the network configuration information are determined.

Referring to FIG. 8, each of end device 100 and switch 200 connected to TSN advertises information of its own node to adjacent nodes. A protocol such as LLDP (Link Layer Discovery Protocol) defined as IEEE 802.1AB, for example, can be used for advertising the information of its own node.

First, each of the end device 100 and the switch 200 connected to the TSN acquires adjacent node information ((1) acquisition of adjacent node information). Neighboring node information is obtained by collecting information advertised by connected end devices 100 and/or switches 200 .

Subsequently, the network controller 300 collects adjacent node information from each of the end devices 100 and switches 200 ((2) collection of adjacent node information). A protocol such as SNMP (Simple Network Management Protocol) or NETCONF may be used to collect adjacent node information.

Then, the network controller 300 generates a TSN topology based on the collected adjacent node information ((3) topology generation). Thus, the network controller 300 generates a topology of TSNs based on neighboring node information collected by each device.

Furthermore, if there is a previously generated topology, the network controller 300 compares the previously generated topology with the currently generated topology ((4) topology matching). Note that when a change in TSN topology is detected by topology collation, it may be added to the network configuration information as a new connection form of the device. That is, the network controller 300 may update network configuration information based on the generated topology.

A topology is generated by the network controller 300 according to the procedure described above.

FIG. 9 is a diagram showing a processing procedure for detecting a topology change by the network controller 300 of the control system 1 according to this embodiment. 9, similarly to FIG. 8, each of end device 100 and switch 200 connected to TSN advertises information of its own node to adjacent nodes.

First, with reference to FIG. 9A, when switch 200-2 connected to TSN detects information advertised by end device 100-2, it obtains adjacent node information using the detected information. Update ((1) Adjacent node information update). The switch 200-2 then notifies the network controller 300 of the updated adjacent node information ((2) notification of adjacent node information).

Referring to FIG. 9B, when switch 200-2 connected to TSN further detects information advertised by end device 100-3, it updates adjacent node information using the detected information. ((1) Neighboring node information update). The switch 200-2 then notifies the network controller 300 of the updated adjacent node information ((2) notification of adjacent node information).

Notification of updated adjacent node information to the network controller 300 can use, for example, an SNMP trap when SNMP is employed. Also, when NETCONF is employed, NETCONF Event Notifications can be used.

A change in TSN (topology) or the like is detected according to the procedure described above.
Some of the procedures for providing TSN settings from the network controller 300 to each of the end devices 100 and switches 200 are now described. For example, it is assumed that OPC Unified Architecture (OPC Unified Architecture), which is internationally standardized as IEC62541, is used as a communication stack for performing data communication between devices using TSN. A combination of TSN and OPC UA is also referred to as “OPC UA over TSN”.

Typical data communication methods between the network controller 300 and the end device 100 include a "Push" mode and a "Request" mode.

Below, an example of the processing procedure in each mode will be shown according to the type of data communication method. For simplicity of explanation, it is assumed that only one switch 200 exists in the TSN.

FIG. 10 is a diagram showing a processing procedure in Push mode in the control system 1 according to this embodiment. Referring to FIG. 10, network controller 300 loads network configuration information and communication setting information ((1) Loading network configuration information and communication setting information).

The network configuration information includes all network configurations (each status of the changeover) caused by the changeover. That is, the network configuration information includes one or more definitions of device topologies that may occur in the TSN. For example, the network configuration information may include both the network configuration shown in FIG. 7(A) and the network configuration shown in FIG. 7(B).

The communication configuration information includes information defining frames exchanged over the TSN. Typically, communication configuration information includes definitions of frames exchanged between end devices 100 .

FIG. 11 is a diagram showing an example of communication setting information used in control system 1 according to the present embodiment. FIG. 11 shows an example of communication setting information for an arbitrary end device 100. As shown in FIG. Referring to FIG. 11, communication setting information includes, for example, information indicating transmission or reception, information indicating a transmission destination or transmission source, data size, and cycle. The communication setting information shown in FIG. 11 is defined for each end device 100 .

By referring to the communication setting information of each end device 100, it is possible to determine the band that must be secured in the TSN.

Referring to FIG. 10 again, each end device 100 loads communication setting information for its own device ((2) Loading communication settings). The communication setting information is the same as that shown in FIG.

Subsequently, the network controller 300 collects TSN capability information from each of the end devices 100 and switches 200 ((3) TSN capability information collection). The TSN capability information is information defining performance information related to the TSN of a device connected to the TSN. For example, the TSN capability information includes information such as transfer rate, the number of traffic classes that can be supported, and the number of ports.

Then, the network controller 300 performs TSN calculation based on the network configuration information, the communication setting information, and the collected TSN capability information ((4) TSN calculation). In TSN calculation, a stream is determined for each exchanged frame, and a communication schedule is determined by considering the bandwidth for each stream (frame). At this time, considering all network configurations caused by the setup change, the communication schedule is determined so that frame transfer can be continued regardless of the network configuration.

Finally, the network controller 300 provides the TSN setting determined by the TSN calculation to the end device 100 and the switch 200 ((5) TSN setting).

Each of the end device 100 and the switch 200 determines and validates the communication schedule 228 according to the TSN setting from the network controller 300 ((6) communication schedule).

According to the procedure as described above, the communication schedule is reflected in the end devices 100 and switches 200 included in the TSN.

FIG. 12 is a diagram showing a processing procedure in Request mode in the control system 1 according to this embodiment. The processing procedure shown in FIG. 12 is executed with all the end devices 100 scheduled to be attached or detached for setup being connected to the TSN. In other words, the state of being connected to the TSN means the change in the network configuration.

Referring to FIG. 12, each end device 100 loads communication setting information for its own device ((1) Loading communication setting). The communication setting information is the same as that shown in FIG. Then, each of the end devices 100 requests the network controller 300 for TSN calculation for providing TSN settings ((2) TSN calculation request). At this time, the TSN calculation request sent from each of the end devices 100 includes communication setting information and TSN capability information.

The network controller 300 loads the network configuration information in response to the TSN calculation request ((3) load network configuration information). The loaded network configuration information includes each state of the changeover. That is, the network configuration information includes all network configurations resulting from the setup change. Subsequently, the network controller 300 collects TSN capability information from each of the switches 200 ((4) TSN capability information collection).

The network controller 300 performs TSN calculation based on the TSN calculation request (including communication setting information and TSN capability information) from the end device 100, the TSN capability information from the switch 200, and the network configuration information ((5 ) TSN calculation). At this time, considering all network configurations caused by the setup change, the communication schedule is determined so that frame transfer can be continued regardless of the network configuration.

Finally, the network controller 300 provides the TSN setting determined by the TSN calculation to the end device 100 and the switch 200 ((6) TSN setting).

Each of the end device 100 and the switch 200 determines and validates the communication schedule 228 according to the TSN setting from the network controller 300 ((7) communication schedule).

According to the procedure as described above, the communication schedule is reflected in the end devices 100 and switches 200 included in the TSN.

<F. Unregistered device>
As mentioned above, the TSN settings are calculated taking into account all network configurations caused by the changeover, but it is also possible that new end devices are connected to the TSN. In this case, the calculation of the TSN setting is performed again. However, since the TSN setting before recalculation may be changed, the user or the like may be notified.

FIG. 13 is a diagram showing another processing procedure in the Request mode in the control system 1 according to this embodiment. FIG. 13 shows the case where the end device 100-4 is newly connected to the TSN. In Request mode, the end device 100 requests the network controller 300 to calculate the TSN, so the network controller 300 can detect the connection to the TSN of a new unregistered end device 100 .

Referring to FIG. 13, the end device 100-4 newly connected to the TSN loads communication setting information for its own device ((1) load communication setting). Then, the end device 100-4 requests the network controller 300 for TSN calculation for providing TSN settings ((2) TSN calculation request).

The network controller 300 loads the network configuration information in response to the TSN calculation request ((3) load network configuration information). Then, the network controller 300 performs TSN calculation based on the TSN calculation request (including communication setting information and TSN capability information) from the end device 100-4 and the information used in the previous TSN calculation ((4 ) TSN calculation). In this way, when a connection form different from the connection form of the device defined in the network configuration information is detected, the network controller 300 sets the TSN so that necessary frame transfer can be realized in the different connection form. Execute the recalculation process.

In the TSN calculation, the network controller 300 then determines whether or not the TSN setting before recalculation (existing TSN setting) can be used. Then, when the TSN setting needs to be reset, the user or the like is notified of the necessity of resetting ((5) Notification of necessity of resetting). In this way, when the network controller 300 determines that the recalculated TSN setting should be reflected, it performs the process of notifying the necessity of the reflection.

Upon receiving approval from the user or the like ((6) Approval), the network controller 300 provides the TSN setting determined by the TSN calculation to the end device 100-4 ((7-1) TSN setting). The determined TSN setting is provided to each of the existing end devices 100 and switches to instruct restart ((7-2) TSN setting+restart). Thus, the network controller 300 takes action to provide the recalculated TSN settings to the devices connected to the TSN in response to the explicit acknowledgment.

Each of the end device 100 and the switch 200 determines and validates the communication schedule 228 according to the TSN setting from the network controller 300 ((8) communication schedule).

Even when a new end device 100 connects to the TSN according to the procedure described above, the new communication schedule is reflected.

As shown in FIG. 13, when the end device 100 connects to the TSN in the Request mode, a TSN calculation request is sent to the network controller 300, so it can be determined whether or not the connected end device 100 is unregistered. .

The network controller 300 determines whether it is necessary to change the band or communication schedule used by other end devices 100 due to the unregistered end device 100 connecting to the TSN. Determine whether the impact on the bandwidth and communication schedules being used is within the permissible range. If the impact on the bandwidth or communication schedule is not acceptable, the network controller 300 asks the user or the like to approve the reconfiguration of the TSN settings. When approval is obtained from the user or the like, the end device 100 and switch 200 connected to the TSN are restarted according to the new TSN setting, and the initial sequence is executed again.

If the impact on the bandwidth or communication schedule is within the permissible range, the TSN settings are provided only to the end device 100-4 newly connected to the TSN.

As a method of notifying the user or the like, a method of using an OPC UA subscription may be used.

<G. Processing Procedure in Network Controller>
Next, a processing procedure in the network controller 300 of the control system 1 according to this embodiment will be described.

FIG. 14 is a diagram showing a processing procedure in Push mode in network controller 300 of control system 1 according to the present embodiment. Each step shown in FIG. 14 is typically implemented by processor 302 of network controller 300 executing network setting program 324 . In the Push mode shown in FIG. 14, when a predetermined condition is satisfied, the process of calculating the TSN setting is started.

Referring to FIG. 14, when the conditions for starting TSN calculation are met (YES in step S100), network controller 300 acquires network configuration information related to the target TSN (step S102), Setting information and TSN capability information are acquired (step S104). That is, the network controller 300 executes a process of acquiring communication setting information defining frames exchanged over the TSN and TSN capability information defining performance information related to the TSN of devices connected to the TSN.

The network controller 300 selects one TSN configuration included in the network configuration information (step S106), and performs TSN calculation including stream setting, bandwidth allocation for each stream, communication schedule determination, etc. (step S108). That is, the network controller 300 executes processing for calculating the TSN setting including the communication schedule of frames in each device based on the network configuration information, the communication setting information, and the TSN capability information. The network controller 300 then sets the TSN setting determined by the TSN calculation as the current TSN setting.

Subsequently, the network controller 300 calculates or updates the TSN setting according to the following procedure so that necessary frame transfer can be realized in any of the connection modes included in the network configuration information.

The network controller 300 selects another TSN configuration included in the network configuration information (step S110), and performs TSN calculations including stream setting, bandwidth allocation for each stream, communication schedule determination, etc. (step S112).

Based on the TSN setting determined by the current TSN calculation, the network controller 300 determines whether or not there is an item for which necessary frame transfer cannot be performed with the current TSN setting (step S114).

If there is an item in which the necessary frame transfer cannot be performed with the current TSN setting (YES in step S114), network controller 300 determines the value of the item in the current TSN setting in which the necessary frame transfer cannot be performed by the current TSN calculation. The value of the item corresponding to the determined TSN setting is changed (step S116). The network controller 300 sets the changed TSN setting as the new current TSN setting.

In this way, the network controller 300 determines whether or not the setting information calculated for one connection form included in the network configuration information can realize necessary frame transfer in another connection form included in the network configuration information. Execute the processing to be performed.

If the required frame transfer can be performed with the current TSN setting (NO in step S114), the process of step S116 is skipped.

Subsequently, the network controller 300 determines whether or not all TSN configurations included in the network configuration information have been selected (step S118).

If selection of all the TSN configurations included in the network configuration information has not been completed (NO in step S118), the processing from step S110 onward is repeated.

If all TSN configurations included in the network configuration information have been selected (YES in step S118), network controller 300 transmits the current TSN settings to each of end device 100 and switch 200 ( step S120). That is, the network controller 300 performs processing to provide TSN settings to devices connected to the TSN.

Thus, the TSN calculation by the network controller 300 is completed.
FIG. 15 is a diagram showing a processing procedure in the Request mode in network controller 300 of control system 1 according to the present embodiment. Each step shown in FIG. 15 is typically implemented by processor 302 of network controller 300 executing network setting program 324 . In the Request mode shown in FIG. 15, the process of calculating the TSN setting is started in response to a request from a device connected to the TSN.

Referring to FIG. 15, when network controller 300 receives a TSN calculation request (YES in step S200), network controller 300 acquires communication setting information and TSN capability information included in the TSN calculation request (step S202), acquires network configuration information related to (step S204). That is, the network controller 300 executes a process of acquiring communication setting information defining frames exchanged over the TSN and TSN capability information defining performance information related to the TSN of devices connected to the TSN.

The network controller 300 selects one TSN configuration included in the network configuration information (step S206), and performs TSN calculation including stream setting, bandwidth allocation for each stream, communication schedule determination, etc. (step S208). That is, the network controller 300 executes processing for calculating the TSN setting including the communication schedule of frames in each device based on the network configuration information, the communication setting information, and the TSN capability information. The network controller 300 then sets the TSN setting determined by the TSN calculation as the current TSN setting.

Subsequently, the network controller 300 calculates or updates the TSN setting according to the following procedure so that necessary frame transfer can be realized in any of the connection modes included in the network configuration information.

The network controller 300 selects another TSN configuration included in the network configuration information (step S210), and performs TSN calculations including stream setting, bandwidth allocation for each stream, communication schedule determination, etc. (step S212).

Based on the TSN setting determined by the TSN calculation this time, the network controller 300 determines whether or not there is an item for which the necessary frame transfer cannot be performed with the current TSN setting (step S214).

If there is an item in which the necessary frame transfer cannot be performed with the current TSN setting (YES in step S214), network controller 300 determines the value of the item in the current TSN setting in which the necessary frame transfer cannot be performed by the current TSN calculation. The value of the item corresponding to the determined TSN setting is changed (step S216). The network controller 300 sets the changed TSN setting as the new current TSN setting.

In this way, the network controller 300 determines whether or not the setting information calculated for one connection form included in the network configuration information can realize necessary frame transfer in another connection form included in the network configuration information. Execute the processing to be performed.

If the required frame transfer can be performed with the current TSN setting (NO in step S214), the process of step S216 is skipped.

Subsequently, the network controller 300 determines whether or not all TSN configurations included in the network configuration information have been selected (step S218).

If selection of all TSN configurations included in the network configuration information has not been completed (NO in step S218), the processing from step S210 onwards is repeated.

If all TSN configurations included in the network configuration information have been selected (YES in step S218), network controller 300 transmits the current TSN settings to each of end device 100 and switch 200 ( step S220). That is, the network controller 300 performs processing to provide TSN settings to devices connected to the TSN.

Thus, the TSN calculation by the network controller 300 is completed.
<H. Note>
The present embodiment as described above includes the following technical ideas.

[Configuration 1]
A communication method in a network according to TSN (Time Sensitive Networking),
a step of obtaining communication setting information defining frames exchanged on the network and capability information defining performance information related to the TSN of a device connected to the network (S104; S204);
A step of calculating a TSN setting including a communication schedule of frames in each device based on network configuration information defining one or more connection types of devices that can occur in the network, the communication setting information, and the capability information ( S106 to S118; S206 to S218);
providing the TSN settings to devices connected to the network (S120; S220);
The step of calculating the TSN setting includes calculating the TSN setting (S110-S118; S210-S218) so as to achieve necessary frame forwarding in any of the topology included in the network configuration information. ,Communication method.

[Configuration 2]
2. The communication method of arrangement 1, wherein the step of calculating the TSN setting is initiated when a predetermined condition is met.

[Configuration 3]
2. The communication method of arrangement 1, wherein calculating the TSN setting is initiated in response to a request from the network-connected device.

[Configuration 4]
In the step of calculating the TSN setting, whether or not the setting information calculated for one connection type included in the network configuration information can realize necessary frame transfer in another connection type included in the network configuration information. 4. The communication method according to any one of configurations 1 to 3, including a step of determining (S114; S214).

[Configuration 5]
further comprising recalculating the TSN setting when a topology different from the device topology defined in the network configuration information is detected so as to achieve necessary frame forwarding in the different topology. , the communication method according to any one of configurations 1 to 4.

[Configuration 6]
6. The communication method of configuration 5, further comprising notifying the need for reflection when it is determined that the recalculated TSN settings should be reflected.

[Configuration 7]
7. The communication method of arrangement 6, further comprising providing the recalculated TSN setting to a device connected to the network in response to an explicit authorization.

[Configuration 8]
each device collecting neighbor node information;
generating a topology of the network based on neighboring node information collected by each device;
and updating said network configuration information based on said generated topology.

[Configuration 9]
A communication system (1) including a network according to TSN (Time Sensitive Networking),
a network controller (300);
one or more devices (100, 200) connected to the network;
The network controller
means for acquiring communication setting information defining frames exchanged on the network and capability information defining performance information related to TSNs of the one or more devices (S104; S204);
Means ( S106 to S118; S206 to S218);
means for providing the TSN settings to the one or more devices (S120; S220);
The communication system, wherein the means for calculating the TSN setting calculates the TSN setting so as to achieve necessary frame forwarding in any of the topologies included in the network configuration information.

[Configuration 10]
A network controller (300) that configures a network according to TSN (Time Sensitive Networking),
means for acquiring communication setting information defining frames exchanged on the network and capability information defining performance information related to TSNs of devices connected to the network (S104; S204);
Means ( S106 to S118; S206 to S218);
means for providing the TSN setting to a device connected to the network (S120; S220);
The communication device, wherein the means for calculating the TSN setting calculates the TSN setting so as to achieve necessary frame forwarding in any of the topology included in the network configuration information.

<I. Advantage>
According to the communication control system according to the present embodiment, when the network configuration (device connection form) is scheduled to be changed due to setup change, etc., the device connection form that may occur in the network is set to one. Alternatively, since the TSN setting is calculated using multiple defined network configuration information, the required communication performance can be maintained in any network configuration. Therefore, even if a setup change occurs, the required communication performance and control performance can be maintained.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

1 control system, 20, 22, 24, 26, 28 links, 30 fieldbuses, 40 field devices, 100 end devices, 102, 302 processors, 104, 304 main memory, 110, 310 network interfaces, 112, 212, 312 transmission and reception Control circuit, 114, 214, 314 transmission circuit, 116, 216, 316 reception circuit, 120, 320 storage, 122 system program, 124 user program, 130 internal bus interface, 132 field bus interface, 134 memory card interface, 136 memory card , 138, 338 bus, 140 I/O unit, 200 switch, 218 transfer engine, 220 queue, 222 gate, 224 distribution circuit, 226 timing control circuit, 228 communication schedule, 300 network controller, 322 OS, 324 network setting program .

Claims (10)

A communication method in a network according to TSN (Time Sensitive Networking),
a step of obtaining communication setting information defining frames exchanged on the network and capability information defining performance information related to the TSN of a device connected to the network;
calculating a TSN setting including a communication schedule of frames in each device based on network configuration information defining one or more connection types of devices that may occur in the network, the communication setting information, and the capability information; ,
providing the TSN settings to devices connected to the network;
The communication method of claim 1, wherein calculating the TSN settings includes calculating the TSN settings so as to achieve necessary frame forwarding in any of the topologies included in the network configuration information. 2. The communication method of claim 1, wherein the step of calculating the TSN setting is initiated when a predetermined condition is met. 2. The communication method of claim 1, wherein calculating the TSN settings is initiated in response to a request from the network-connected device. In the step of calculating the TSN setting, whether or not the setting information calculated for one connection type included in the network configuration information can realize necessary frame transfer in another connection type included in the network configuration information. A communication method according to any one of claims 1 to 3, comprising the step of determining further comprising recalculating the TSN setting when a topology different from the device topology defined in the network configuration information is detected so as to achieve necessary frame forwarding in the different topology. , the communication method according to any one of claims 1 to 4. 6. The communication method of claim 5, further comprising notifying the necessity of reflection when it is determined that the recalculated TSN setting should be reflected. 7. The communication method of claim 6, further comprising providing the recalculated TSN settings to devices connected to the network in response to explicit approval. each device collecting neighbor node information;
generating a topology of the network based on neighboring node information collected by each device;
and updating said network configuration information based on said generated topology. A communication system including a network according to TSN (Time Sensitive Networking),
a network controller;
one or more devices connected to the network;
The network controller
means for acquiring communication setting information defining frames exchanged on the network and capability information defining performance information related to TSNs of the one or more devices;
means for calculating a TSN setting including a communication schedule of frames in each device, based on network configuration information defining one or more connection types of devices that can occur in the network, the communication setting information, and the capability information; ,
means for providing the TSN settings to the one or more devices;
The communication system, wherein the means for calculating the TSN setting calculates the TSN setting so as to achieve necessary frame forwarding in any of the topologies included in the network configuration information. A network controller that configures a network according to TSN (Time Sensitive Networking),
means for acquiring communication setting information defining frames exchanged on the network and capability information defining performance information related to TSN of a device connected to the network;
means for calculating a TSN setting including a communication schedule of frames in each device, based on network configuration information defining one or more connection types of devices that can occur in the network, the communication setting information, and the capability information; ,
means for providing said TSN configuration to a device connected to said network;
The communication device, wherein the means for calculating the TSN setting calculates the TSN setting so as to achieve necessary frame forwarding in any of the topology included in the network configuration information.

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