CN115776732A

CN115776732A - Network bridge determination method, data scheduling method and electronic equipment

Info

Publication number: CN115776732A
Application number: CN202111037798.3A
Authority: CN
Inventors: 韦安妮
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2021-09-06
Filing date: 2021-09-06
Publication date: 2023-03-10

Abstract

The invention provides a network bridge determination method, a data scheduling method and electronic equipment, and relates to the technical field of communication, wherein the network bridge determination method is applied to a Centralized Network Controller (CNC) of a Time Sensitive Network (TSN) system, the TSN system also comprises a plurality of network bridges, the plurality of network bridges comprise at least one TSN network bridge device and a mobile communication system, and the network bridge determination method comprises the following steps: receiving current network state information sent by a plurality of network bridges; determining a combined TSN bridge and TSN scheduling strategy information of the combined TSN bridge based on service information sent by end equipment and current network state information of a plurality of bridges; the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, wherein N is an integer, and the TSN scheduling policy information is used for data scheduling of the combined TSN bridge based on the TSN scheduling policy information, so that the data scheduling performance can be improved.

Description

Network bridge determining method, data scheduling method and electronic equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a network bridge determination method, a data scheduling method, and an electronic device.

Background

TSN (Time Sensitive Networking) is a technology extending from the field of video and audio data to the fields of industry and automobiles. In the process of data forwarding, the TSN can perform queue scheduling for the service data of different priorities of the industrial internet, thereby realizing quality differentiation guarantee. At present, how to perform convergence deployment on a mobile communication system (for example, fifth generation mobile communication, i.e., 5G) and a TSN technology in an industrial internet has become one of the hot spots of research in the industrial industry, academic circles, standard organizations, and the like, and at present, a convergence architecture of a TSN and a mobile communication system mainly adopts a bridging technology, that is, the mobile communication system operates as a TSN bridge of the TSN system.

Currently, in the process of data scheduling (i.e. data transmission), a TSN and mobile communication system fusion system employs a scheduling mechanism for maintaining and forwarding, that is, a data packet only needs to open a gate for data transmission at a predetermined period, so as to control the time delay of the data packet passing through the fusion system. For example, a data packet arrives at an entrance of a mobile communication system at time T1, the transmission delay of the mobile communication system is X milliseconds, the data packet is sent at exit side of the mobile communication system by T1+ X milliseconds, the next data packet arrives at the entrance of the mobile communication system at time T2, the transmission delay of the mobile communication system is X-1 milliseconds, the data packet is sent at exit side of the mobile communication system by 1 millisecond before the exit side of the mobile communication system, and if jitter occurs, the data packet needs to wait for 1 millisecond, and the data packet is sent by T2+ X milliseconds, so that 1 millisecond jitter caused by the transmission of the data packet through the mobile communication network is eliminated. The hold and forward scheduling mechanism can eliminate jitter induced by early data packets. However, the uncertainty of the mobile communication network causes the accuracy of the transmission time of the whole mobile communication system to be poor, and the existing fusion system of the TSN and the mobile communication system cannot eliminate jitter caused by delay in the scheduling process of a data packet that is achieved by scheduling delay, resulting in poor data scheduling performance.

Disclosure of Invention

The embodiment of the invention provides a network bridge determination method, a data scheduling method and electronic equipment, and aims to solve the problem of the existing data scheduling performance.

In order to solve the technical problem, the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a bridge determination method, applied to a centralized network controller CNC of a time-sensitive network TSN system, where the TSN system further includes a plurality of bridges, where the plurality of bridges includes at least one TSN bridge device and a mobile communication system, and the method includes:

receiving current network state information sent by the plurality of network bridges;

determining a joint TSN bridge and TSN scheduling strategy information of the joint TSN bridge based on service information sent by end equipment and current network state information of the bridges;

wherein the joint TSN bridge includes the mobile communication system and N of the at least one TSN bridge devices, where N is an integer, and the TSN scheduling policy information is used by the joint TSN bridge to perform data scheduling based on the TSN scheduling policy information.

In a second aspect, an embodiment of the present invention provides a data scheduling method, which is applied to a target bridge device in multiple bridges of a time sensitive network TSN system, where the target bridge device is a bridge device in the multiple bridges, the TSN system further includes a centralized network controller CNC, the multiple bridges include at least one TSN bridge device and a mobile communication system, and the method includes:

sending current network state information of the target network bridge equipment to the CNC;

receiving bridge information sent by the CNC based end device and current network information of the plurality of bridges, wherein the bridge information includes information of a combined TSN bridge and TSN scheduling policy information, the combined TSN bridge includes the mobile communication system and N TSN bridge devices in the at least one TSN bridge device, N is an integer, and the target bridge device is a network device in the combined TSN bridge;

and performing data scheduling based on the TSN scheduling strategy information.

In a third aspect, an embodiment of the present invention provides a data scheduling method, which is applied to a time sensitive network TSN system, where the TSN system includes a centralized network controller CNC and a plurality of bridges, where the plurality of bridges includes at least one TSN bridge device and a mobile communication system;

the method comprises the following steps:

the plurality of network bridges sending current network state information to the CNC;

the CNC determines a combined TSN bridge and TSN scheduling policy information of the combined TSN bridge based on service information sent by end equipment and current network state information of the plurality of bridges, wherein the combined TSN bridge comprises the mobile communication system and N TSN bridge devices in the at least one TSN bridge device, and N is an integer;

and the joint TSN bridge carries out data scheduling based on the TSN scheduling strategy information.

In a fourth aspect, an embodiment of the present invention provides an electronic device, which is a centralized network controller CNC in a time-sensitive network TSN system, where the TSN system further includes a plurality of bridges, the plurality of bridges include at least one TSN bridge device and a mobile communication system, and the electronic device includes:

a first receiving module, configured to receive current network state information sent by the plurality of bridges;

the determining module is used for determining a combined TSN bridge and TSN scheduling policy information of the combined TSN bridge based on service information sent by end equipment and current network state information of the bridges;

In a fifth aspect, an embodiment of the present invention provides an electronic device, which is a device in a plurality of bridges of a time-sensitive network TSN system, where the TSN system further includes a centralized network controller CNC, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system, and the electronic device includes:

the first sending module is used for sending the current network state information of the electronic equipment to the CNC;

a second receiving module, configured to receive bridge information sent by the CNC based on service information of an end device and current network information of the multiple bridges, where the bridge information includes a joint TSN bridge and TSN scheduling policy information, where the joint TSN bridge includes the mobile communication system and N TSN bridge devices of the at least one TSN bridge device, where N is an integer, and the target bridge device is a network device of the joint TSN bridge;

and the scheduling module is used for scheduling data based on the TSN scheduling strategy information.

In a sixth aspect, embodiments of the present invention provide a time sensitive network TSN system, where the TSN system includes a centralized network controller CNC and a plurality of bridges, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system;

In a seventh aspect, an embodiment of the present invention provides an electronic device, including a transceiver and a processor, where the electronic device is a centralized network controller CNC in a time-sensitive network TSN system, the TSN system further includes a plurality of bridges, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system;

the transceiver is used for receiving the current network state information sent by the plurality of network bridges;

the processor is configured to determine a joint TSN bridge and TSN scheduling policy information of the joint TSN bridge based on service information sent by an end device and current network state information of the plurality of bridges;

In an eighth aspect, an embodiment of the present invention provides an electronic device, including a transceiver and a processor, where the electronic device is a device in a plurality of bridges of a time-sensitive network TSN system, the TSN system further includes a centralized network controller CNC, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system;

the transceiver is used for sending the current network state information of the electronic equipment to the CNC;

the transceiver is configured to receive network bridge information sent by the CNC based end device and current network information of the plurality of network bridges, where the network bridge information includes a joint TSN bridge and TSN scheduling policy information, where the joint TSN bridge includes the mobile communication system and N TSN bridge devices of the at least one TSN bridge device, where N is an integer, and the target network bridge device is a network device of the joint TSN bridge;

the processor is configured to perform data scheduling based on the TSN scheduling policy information.

In a ninth aspect, an embodiment of the present invention provides an electronic device, including: a processor, a memory and a program stored on the memory and executable on the processor, the program, when executed by the processor, implementing the steps of the bridge determination method of the first aspect.

In a tenth aspect, an embodiment of the present invention provides an electronic device, including: a processor, a memory and a program stored on the memory and executable on the processor, the program, when executed by the processor, implementing the steps of the bridge determination method of the second aspect.

In an eleventh aspect, an embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of the bridge determination method according to the first aspect; or the computer program when executed by a processor implements the steps of the bridge determination method of the second aspect described above.

In the method of this embodiment, the traffic information sent by the end device and the current network state information of the multiple bridges may be used to determine the TSN scheduling policy information of the joint TSN bridge and the joint TSN bridge, and the joint TSN bridge may perform data scheduling based on the TSN scheduling policy information, so that the data scheduling process is not directly controlled by the delay of a single bridge, but the data scheduling is performed by the TSN scheduling policy information of the joint TSN bridge, and even if a delay time of a packet by a certain bridge is long, the packet may be buffered by other bridges in the joint TSN bridge, and the joint TSN bridge is taken as a whole to perform data scheduling by the corresponding TSN scheduling policy information, which may improve the data scheduling performance.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive exercise.

Fig. 1 is a flowchart of a bridge determination method according to an embodiment of the present invention;

fig. 2 is a flowchart of a data scheduling method according to an embodiment of the present invention;

fig. 3 is a flowchart of another data scheduling method provided by an embodiment of the present invention;

FIG. 4 is a TSN and industrial Internet architecture diagram;

FIG. 5 is a schematic diagram of a 5G and TSN fusion system;

FIG. 6 is a schematic diagram of a TAS time-aware scheduling scheme;

FIG. 7 is a schematic diagram of a method for eliminating delay jitter;

fig. 8 is a schematic diagram of a bridge determination method according to an embodiment of the present invention;

fig. 9 is a second schematic diagram of a bridge determination method according to an embodiment of the present invention;

fig. 10 is an interaction diagram of a bridge determination method according to an embodiment of the present invention;

fig. 11 is a third schematic diagram of a bridge determination method according to an embodiment of the present invention;

fig. 12 is a second interaction diagram of a bridge determination method according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of an electronic device according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of another electronic device provided in the embodiment of the present invention;

fig. 15 is a schematic structural diagram of an electronic device according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of another electronic device according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a flowchart of a bridge determination method provided in an embodiment of the present invention, which is used for a centralized network controller CNC of a time-sensitive network TSN system, where the TSN system further includes a plurality of bridges, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system, as shown in fig. 1, the method includes the following steps:

step 101: current network state information sent by the plurality of bridges is received.

Multiple bridges in a TSN system may send their current Network state information to a CNC (Centralized Network Configuration) in the TSN system. As an example, the network status information may include, but is not limited to, at least one of network topology information, uplink and downlink transmission delay information, network load information, and network coverage, etc., i.e., in one example, the current network status information may include at least one of current network topology information, current uplink and downlink transmission delay information, current network load information, and current network coverage.

Step 102: determining a combined TSN bridge and TSN scheduling strategy information of the combined TSN bridge based on service information sent by end equipment and current network state information of a plurality of bridges;

the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, wherein N is an integer, and TSN scheduling policy information is used for data scheduling of the combined TSN bridge based on the TSN scheduling policy information.

The end device can send the corresponding service information to the CNC, the CNC can determine the TSN scheduling strategy information of the combined TSN bridge and the combined TSN bridge based on the service information and the current network information sent by the bridges, and it can be understood that the combined TSN bridge as a whole can perform data scheduling based on the TSN scheduling strategy information. As an example, the traffic information may include at least one of traffic transmission characteristic and transmission quality requirement information.

In one embodiment, receiving current network state information sent by a plurality of bridges includes:

receiving current network state information sent by at least one TSN bridge device;

under the condition that a joint TSN bridge needs a mobile communication system based on service information and historical network state information of a plurality of bridges, sending a network state reporting request to the mobile communication system;

and receiving the current network state information sent by the mobile communication system based on the network state reporting request.

Each TSN bridge device in at least one TSN bridge device respectively sends corresponding current network state information to a CNC, for a mobile communication system, the CNC needs to determine whether the mobile communication system needs to be incorporated into a data transmission link as a bridge in a combined TSN bridge according to service information and historical state information of a plurality of bridges, if the mobile communication system needs to be determined, the CNC sends a network state reporting request to the mobile communication system, and receives the current network state of the mobile communication system sent by the mobile communication system in response to the request. The subsequent CNC can determine the combined TSN bridge and TSN scheduling strategy information of the combined TSN bridge by using current network state information and service information sent by the bridges so as to improve the accuracy of the determined combined TSN bridge.

In one embodiment, the network status reporting request includes at least one of:

reporting a trigger condition;

reporting the period;

and reporting the information types.

After receiving the network state reporting request, the mobile communication system can acquire the information included in the network state reporting request, the mobile communication system can report the current network state information of the mobile communication system in response to the network state request, the CNC acquires the current network state information reported by the mobile communication system, and the CNC can determine a combined TSN bridge by using the service information sent by the end equipment, the current network state information of at least one TSN bridge equipment and the current network state information of the mobile communication system so as to improve the accuracy of the combined TSN bridge.

In one embodiment, after determining the joint TSN bridge and the TSN scheduling policy information of the joint TSN bridge, the method further includes:

and sending bridge information to each bridge device in the joint TSN bridge, wherein the bridge information comprises information of the joint TSN bridge and TSN scheduling policy information.

The CNC informs each bridge device in the combined TSN bridge of the determined information (such as identification) of the combined TSN bridge and the TSN scheduling policy information, so that the bridge devices can clearly combine the TSN bridge and the corresponding TSN scheduling policy information, and in the subsequent data scheduling process, data scheduling can be performed by using the TSN scheduling policy information of the whole combined TSN bridge, and the data scheduling performance is improved.

In one embodiment, the bridge information further comprises at least one of:

the transmission direction of the joint TSN bridge;

and TSN service identification information, wherein the TSN service identification information is used for identifying the TSN service stream.

In the process of transmitting data through the mobile communication system, there is a data transmission direction, for example, the uplink transmission direction and the downlink transmission direction may be deducted, and the transmitted bridge information may further include the transmission direction of the associated bridge. In addition, the bridge information may further include TSN traffic identification information, and the TSN traffic stream may be identified by the TSN traffic identification information.

In one embodiment, after sending bridge information to each bridge device in the federated TSN bridge, the method further comprises:

and receiving the confirmation message sent by each bridge device in the joint TSN bridge based on the bridge information.

After the bridge equipment in the combined TSN bridge receives the bridge information sent by the CNC, a confirmation message can be returned to the CNC to confirm that the bridge information is received, the successful receiving of the bridge information is indicated, and the reliability of the transmission of the bridge information can be ensured.

In one embodiment, the TSN scheduling policy information includes at least one of:

scheduling period

Scheduling priority.

A scheduling period may be understood as a data gating period, for example, where the scheduling period is M, and data enters the joint TSN bridge at time T and needs to be output from the joint bridge at time T + M. In addition, in order to ensure the ordered data scheduling, the TSN scheduling policy information may also include a scheduling priority, which may be understood as a data scheduling priority, and data may be scheduled using the scheduling priority.

Referring to fig. 2, fig. 2 is a flowchart of a bridge determining method provided in an embodiment of the present invention, for a target bridge device in multiple bridges of a time sensitive network TSN system, and for multiple bridges of the time sensitive network TSN system, as shown in fig. 2, the method includes the following steps:

step 201: sending the current network state information of the target network bridge equipment to the CNC;

step 202: receiving CNC service information based on end equipment and bridge information sent by current network information of a plurality of bridges;

the bridge information comprises information of a combined TSN bridge and TSN scheduling policy information, wherein the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, N is an integer, and a target bridge device is a network device in the combined TSN bridge;

step 203: and performing data scheduling based on the TSN scheduling strategy information.

In one embodiment, the bridge information also includes the transmission direction of the federated TSN bridge;

and the data in the transmission direction of the combined TSN bridge is output at a target time, wherein the target time is the sum of the first time and the scheduling period in the TSN scheduling policy information, and the first time is the time when the data enters the combined TSN bridge.

Referring to fig. 3, fig. 3 is a flowchart of a data scheduling method provided by an embodiment of the present invention, for a time-sensitive network TSN system, where the TSN system includes a centralized network controller CNC and a plurality of bridges, and the plurality of bridges includes at least one TSN bridge device and a mobile communication system; as shown in fig. 3, the method comprises the steps of:

step 301: a plurality of network bridges send current network state information to the CNC;

step 302: the CNC determines a combined TSN bridge and TSN scheduling strategy information of the combined TSN bridge based on service information sent by end equipment and current network state information of a plurality of bridges;

the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, wherein N is an integer;

step 303: and the joint TSN bridge schedules data based on the TSN scheduling strategy information.

It should be noted that, after determining the TSN scheduling policy information of the joint TSN bridge and the joint TSN bridge, the CNC needs to send bridge information to each bridge device in the joint TSN bridge, where the bridge information includes information of the joint TSN bridge and TSN scheduling policy information.

The process of the above method is described in detail below with an embodiment.

TSN is a technology extending from the field of video and audio data to the industrial field and the automotive field. The TSN originally comes from the application requirements in the field of audio and video, and at that time, the technology is called AVB, and since a higher bandwidth and a maximum real-time are required for an audio and video network, high-quality audio and video can be transmitted better by means of the AVB. In 2006, the AVB av bridging task group was established and the problem of real-time isochronous transmission of data in av networks was successfully addressed in the following years. As a result of the attention from those in the automotive and industrial fields, in 2012, the AVB task group expanded the application requirements and applicability of time-deterministic ethernet in its course, and changed the task group name to the current one: TSN task group. The TSN is a new generation network standard based on ethernet, and has functions of ensuring real-time performance, such as time synchronization and delay guarantee. While the TSN fully centralized mode is not the only way to handle time sensitive network traffic, it is best illustrated among the three modes. The fully centralized network management mode exists with a central management device that performs two key functions. As shown in fig. 4, these functions are represented by a Central User Controller (CUC), which can be understood as a user centralized configuration, and a Centralized Network Controller (CNC), which can also be understood as a centralized network configuration.

And (4) CUC node: and the network system user side interface is used for managing the industrial application system and providing network service configuration requirements between end-to-end application systems for the CNC through the UNI interface.

CNC node: the system has the comprehensive configuration capability of the time-sensitive network relevant characteristics defined by IEEEstd802.1Q-2018, and relevant configuration is issued to the network nodes through the southbound interface.

The forwarding device node: the system is responsible for actual message forwarding and supports the execution of related TSN characteristics; according to the application scenario and the network element position in the network, the TSN forwarding devices are divided into 3 types of gateways, bridge devices, and end devices: (1) a gateway device: the method is mainly deployed at the edge of a time-sensitive network domain, and supports the realization of intercommunication among a cross-TSN domain, a TSN domain and a non-TSN domain at a data link layer, a network layer and an application layer. (2) The bridge device: the method is mainly deployed inside the TSN domain, and interconnection and intercommunication of business units (workshops, production lines and equipment) inside the TSN domain are achieved. It is proposed within the factory to deploy bridge devices, i.e., core, aggregation, access layer devices, in a three-layer architecture. The core layer equipment is deployed in a factory-level machine room, so that interconnection and intercommunication among all workshops in a factory are realized; the convergence layer equipment is deployed in a workshop-level machine room to realize interconnection among different production lines in a workshop and between a centralized controller and the equipment; the receiving equipment is deployed in a production field to realize communication protocol conversion of communication interfaces of field equipment, sensors and the like and is interconnected and communicated with the controller and the detection monitoring device. (3) End equipment: the industrial equipment with the TSN function comprises equipment such as a controller, a PLC, a servo, an I/O and the like.

Network management node: the system can be physically combined with the CNC node and is responsible for fault monitoring and resource management of the network equipment.

The industrial internet can realize the network interconnection of all elements of people, machines and things. The industrial internet platform can tightly connect and merge equipment, production lines, factories, suppliers, products and customers. The 5G is a key enabling technology of the industrial Internet, the industrial Internet is one of important application scenes of the 5G, and the 5G + industrial Internet is an important direction for enabling digitization, wireless and intelligence of intelligent factories.

The large bandwidth, the low time delay and the high reliability of the 5G network can meet the requirements of flexible mobility and differentiated service processing capacity of industrial equipment, promote the wireless application of various Augmented Reality (AR)/Virtual Reality (VR) terminals, robots, automatic Guided Vehicles (AGV), on-site production line equipment and the like, and help flexible production of factories to be popularized on a large scale. The industrial internet brings a wide application scene to 5G and also brings challenges. For example, some industrial applications may require a network with 1ms delay, 1 μ s jitter, and 99.999999% network transmission quality.

The Time Sensitive Network (TSN) is one of important technologies for realizing low-delay, high-reliability and deterministic transmission of industrial interconnection, and the 5G + TSN is an important basis for realizing wireless and flexible manufacturing of the industrial interconnection in the future. When the TSN forwards data, queue scheduling can be performed for the service data of different priorities of the industrial internet, so that quality differentiation is guaranteed. In an industrial internet scenario, the TSN may be modeled and defined for traffic flow characteristics related to various industrial applications, and on this basis, different priorities and scheduling mechanisms are provided.

The types of traffic flow of the industrial internet are very many, such as video, audio, synchronous real-time control flow, event, configuration & diagnosis, etc., and table 1 is a typical classification example of the traffic flow of the industrial internet. As can be seen from Table 1, different traffic flows in the industrial Internet have different Service Level Agreement (SLA) requirements. According to the periodic division, the service flow can be divided into a periodic flow and a non-periodic flow. The synchronous real-time stream has the highest requirement on time delay, and the time delay is mainly used for motion control and is characterized in that the packet is sent periodically, and the period of the packet is generally less than 2ms; the length of data sent in each period is relatively stable and generally does not exceed 100B; end-to-end transmission has a time limit requirement that data needs to arrive at the opposite end before a certain absolute time. Event, configuration & diagnosis, best Effort class no-delay specific requirements; the audio and video categories are mainly dependent on the frame rate and the sampling rate; the periodic loop and network control classes have latency requirements but are lower than the synchronous real-time class.

TABLE 1

At present, how to implement convergence deployment on 5G and TSN technologies in the industrial internet has become one of the hotspots of research of the industrial, academic and standard organizations, especially 3 rd generation partnership project (3 GPP), and the standardization work of the 5G TSN has been started and a basic convergence architecture has been established. At present, a TSN and 5G convergence architecture mainly adopts a bridging technology, that is, a 5G system is operated as a TSN bridge of a TSN system.

As shown in fig. 5, the 5G overall network includes the terminal, radio, bearer and core networks, acting as a logical bridge in the TSN. And the TSN and the 5G network perform conversion and intercommunication of a user plane and a control plane through the function of the TSN converter. The 5G TSN converter comprises a device side TSN converter (DS-TT) and a network side TSN converter (NW-TT), wherein the DS-TT is located at a terminal side, and the NW-TT is located at a network side. The 5G network is transparent to the TSN, with TSN ingress and egress ports provided through DS-TT and NW-TT. The TSN AF is used as an information conversion network element of a CNC and a 5GS of a TSN system, maps a control instruction of the TSN into a parameter which can be understood by the 5GS, converts information reported by the 5GS into a standard format of the TSN, supports 802.1Qcc and 802.1AB management interfaces, and is communicated with the TSN system, such as 5GS capacity and topology reporting, stream forwarding rule receiving and the like. Wherein, AF is an application function, NEF: network exposure function or network open function, AMF: access and mobility management functions, NW-TT: network side TSN converter, UDM: unified data management platform, DS-TT: terminal side TSN converter or device side TSN converter, PCF: policy control function, UE: user equipment, gbb: 5G base station, SMF: session management function, UPF: user plane functions.

The TSN working group proposes a Time Aware Shaper (TAS), which is a scheduling mechanism designed for lower Time granularity and more severe industrial control applications, and is currently adopted by enterprises in the field of industrial automation. The time-aware scheduling is proposed in the ieee802.1qbv standard M1, and the main idea is to suspend other flows in a certain specific time slice at each port of the switching node, and only allow the transmission of the time-sensitive flows, thereby isolating the influence of the common flows on the time-sensitive flows in the time dimension.

The principle of the TAS mechanism is shown in fig. 6, where at each output port of the switching node there are 8 output queues with priorities between 0 and 7. The port fetches the packets from the queue to send according to the period, each period is divided into a plurality of time slices, each time slice can only fetch the packets from one or more selected queues to send, and the specific queue selection strategy is determined by the queue selection control list. The queue selection control list is composed of a binary group { time slice, queue state label }, wherein the 'queue state label' is identified by 8 bits {0,1} binary number, corresponding to 8 priority queues. "1" represents that the queue is selected, namely in the current time slice, and the packet is taken from the queue and sent; a "0" represents that the queue is closed, i.e. the current time slice, and the queue is not allowed to transmit packets. As shown in fig. 6, in the T02 time slice, only queue 7 is labeled "1", and the other queues are labeled "0", so that the time slice only allows queue 7 to send packets.

The 5G TSN can adopt TSCAI to describe the traffic characteristics of industrial Internet traffic, including communication modes (periodic and non-periodic), traffic directions (uplink and downlink), and arrival time of traffic; and secondly, the DS-TT and the NW-TT adopt a maintaining and forwarding scheduling mechanism according to the characteristic information of the service flow and the flow scheduling strategy so as to reduce the time delay jitter. As shown in table 2, the 5G TSN supports a traffic scheduling maintaining and forwarding mechanism defined in the institute of electrical and electronics engineers standard (ieee 802.11 qbv), and a data packet of the 5G TSN can control a time delay of a message passing through the 5G TSN only by opening a gate control for data transmission at a predetermined period. For example, for industrial control traffic, both data and gated transmission periods are 20ms. The 1 st message arrives at a 5G entrance (DS-TT or NWTT) at T1, the transmission delay of a 5G system is 10ms, and a 5G system sends the message at an exit side T1+10 ms; the transmission delay of the 2 nd packet 5G system is 9ms, which leads the 5G system exit by 1ms, and jitter occurs, as shown in fig. 7, at this time, the packet 2 needs to wait for 1ms, and is sent only in T1+30ms, so that the delay of the packet 2 in the 5G system is extended to 10ms, and thus 1ms jitter caused by the packet being transmitted through the 5G network is eliminated. Keep-alive forwarding can eliminate jitter caused by early messages, but cannot eliminate jitter caused by delay.

TABLE 2

That is, for the current scheme of 5G + TSN, the end-to-end architecture of the 5G system is used as a TSN bridge of the TSN system, and when the CNC allocates a delay requirement to each TSN bridge in the link, a certain delay, such as 5ms, for a data to stay in the TSN bridge is given according to the judgment of the network state. If the data arrives in advance, the buffer waiting is carried out at the UPF or UE end, and if the data arrives in delay, no other better solution exists at present, which is considered as the scheduling error of the whole TSN system. The 5G system is used as a wireless system, the uncertainty of an air interface link of the wireless system causes poor accuracy of the whole 5GS transmission time, and especially under a harsh time delay service demand scene, a time delay scheduling scheme of the 5G + tsn system brings great challenges.

The main idea of the present invention is that a centralized network controller CNC of a TSN system adjusts in real time the architecture of a TSN Bridge to which 5GS (5G system) belongs in a 5G + TSN architecture according to traffic delay requirements and the state of the 5G network, and forms a Combined TSN Bridge (Combined TSN Bridge) with higher delay jitter tolerance by matching with adjacent TSN switches in TSN links, such as Combined TSN Bridge a, combined TSN Bridge B, or Combined TSN Bridge C of fig. 8, where TSN Bridge1 is TSN Bridge1, TSN Bridge2 is TSN Bridge2, ran is a wireless access network, AN is AN access network, and End station is AN End device, and by combining TSN bridges, uncertainty of the 5G system relative to data transmission delay of a wired switch can be buffered, so that the Combined deployment of the 5G network is more flexible, and the deterministic service transmission performance is ensured while the 5G network enjoys convenience.

In one embodiment, a TSN control system (TSN control system, e.g., CNC) determines a Combined TSN Bridge including 5GS TSN bridges and 0,1, or more non-5 GS TSN bridges (TSN Bridge devices) based on traffic information to be transmitted and network topology of TSN bridges (including 5GS as a whole TSN bridges) that can be used in the current network and network status information of the respective TSN bridges, etc. The Combined TSN Bridge has a transmission direction, for example, an uplink direction or a downlink direction, according to different requirements of service characteristics and transmission performance of uplink and downlink services. The introduction of Combined TSN Bridge enables 5GS as a component of Combined TSN Bridge to not directly receive strict gating control of each TSN Bridge unit by a TSN control system in data transmission processing. At the time of better channel condition, the data can be transmitted quickly, and at the time of worse channel condition, because of the buffer of other pair of bridges, the late data can be scheduled faster at the TSN Bridge at the end, and sent to the outlet of Combined TSN Bridge before the arrival time determined by the TSN control system for the whole Combined TSN Bridge comes.

As shown in fig. 9, the CNC determines the downstream direction according to the traffic information to be transmitted, the network topology of the TSN Bridge (including 5GS as a whole TSN Bridge) that can be used in the current network, the network status information of each TSN Bridge, and the like, the 5GS and the TSN Bridge1 form a Combined TSN Bridge a, and the data gating period allocated to the Combined TSN Bridge a is Combined TSN Bridge a day = M milliseconds, that is, after the downstream data enters from the UPF at time T, the downstream data needs to reach the downstream exit of the TSN Bridge at time T + M. The downstream entry direction of DS-TT and TSNBridge 1 as Combined TSN Bridge A internal entity does not need to execute the gating strategy.

As shown in fig. 10, the flow of the method of the present embodiment is as follows:

the TSN control system acquires network state information of the TSN Bridge (including 5 GS) from the TSN Bridge, which may include, but is not limited to, network topology information, uplink and downlink transmission delay information, and the like, for example.

The TSN control system obtains the service information of the application, including the service transmission characteristics (such as the information of the service period in the uplink and downlink directions) and the transmission quality requirement information (such as reliability, time delay, jitter, etc.).

The TSN control system determines the Combined TSN Bridge containing 5GS tsnbridge and 0,1 or more non-5 GS TSN bridges and TSN scheduling policy information such as data scheduling period, etc. that the Combined TSN Bridge needs to execute, based on the traffic information to be transmitted and the network state information of the TSN bridges that can be used in the current network (including 5GS as a whole TSN Bridge).

The TSN control system sends Bridge information, which may include the transmission direction, the Combined TSN Bridge information, and TSN scheduling policy information, to the TSN Bridge within the Combined TSN Bridge.

Upon receiving a Bridge by a TSN Bridge (including 5 GS) within a Combined TSN Bridge, an acknowledgement message may be sent to the TSN control system.

In another embodiment, the TSN control system (e.g., CNC) flexibly adjusts the composition of the Combined TSN Bridge according to the transmitted traffic information and the network topology information of the TSN bridges (including the 5GS as a whole TSN Bridge) that can be used in the current network and the network status information of the individual TSN bridges, i.e., the Combined TSN Bridge may change according to the change of the network status of the Bridge (especially the network status of the 5 GS).

As shown in fig. 11, the CNC determines the downstream direction according to the traffic information to be transmitted and the network topology information of the TSN bridges (including 5GS as a whole TSN Bridge) that can be used in the current network and the network status information of each TSN Bridge, and the 5GS and the TSN Bridge2 form a Combined TSN Bridge B. When the 5GS network state changes, the CNC can determine to combine 5GS with TSN Bridge1 and TSN Bridge2 to form a Combined TSN Bridge C instead of Combined TSN Bridge B. At this time, the uplink Combined TSN Bridge C internal entities of DS-TT and NW-TT do not need to execute the gating strategy, and the gating strategy is executed by TSN Bridge1 and TSN Bridge 2.

As shown in fig. 12, the flow of the method of the present embodiment is as follows:

the TSN control system acquires network topology information of the TSN Bridge, network status information of the TSN Bridge, and the like from the TSN Bridge (including 5 GS).

The TSN control system determines whether 5GS needs to be incorporated into the data transmission link (i.e., determines whether 5G connection needs to be used) and whether 5GS needs to be used for real-time network status reporting according to the traffic information to be transmitted and the network topology information of the TSN bridges (including 5GS as a whole TSN Bridge) that can be used in the current network and the historical network status information of each TSN Bridge.

If necessary, the TSN control system sends a network state reporting request to the 5GS, and acquires current network state information sent by the 5 GS;

the TSN control system determines the Combined TSN Bridge containing 5GS tsnbridge and 0,1 or more non-5 GS TSN bridges and TSN scheduling policy information that the Combined TSN Bridge needs to execute, based on the traffic information to be transmitted and the network topology information of the TSN bridges (including 5GS as a whole TSN Bridge) that can be used in the current network and the current network state information of the respective TSN bridges.

And if the network state changes and the reporting trigger condition is met, updating the network state information to the TSN control system by the 5 GS.

The TSN control system determines the Combined TSN Bridge again, and transmits Bridge information to the TSN Bridge in the updated Combined TSN Bridge, which may include the transmission direction of the updated Combined TSN Bridge, the updated Combined TSN Bridge information, the updated TSN scheduling policy information of the Combined TSN Bridge, and the like. The TSN control system triggers the release of the originally old Combined TSN Bridge information.

In the method of the present invention, a centralized network controller CNC of a TSN system can adjust a TSN bridge architecture to which 5GS belongs in a 5G + TSN architecture in real time according to a service delay requirement and a network state of a 5G network, and a flexible TSN bridge with higher delay jitter tolerance is formed by matching with an adjacent TSN switch in a TSN link, and policy configuration is performed.

Referring to fig. 13, fig. 13 is a schematic structural diagram of an electronic device according to an embodiment of the present invention, the electronic device is a centralized network controller CNC in a time-sensitive network TSN system, the TSN system further includes a plurality of bridges, the plurality of bridges includes at least one TSN bridge device and a mobile communication system, as shown in fig. 13, the electronic device 1300 includes:

a first receiving module 1301, configured to receive current network state information sent by multiple network bridges;

a determining module 1302, configured to determine a joint TSN bridge and TSN scheduling policy information of the joint TSN bridge based on service information sent by an end device and current network state information of multiple bridges;

the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, wherein N is an integer, and the TSN scheduling policy information is used for performing data scheduling on the basis of the TSN scheduling policy information by the combined TSN bridge.

In one embodiment, a first receiving module includes:

the first sub-receiving module is used for receiving current network state information sent by at least one TSN bridge device;

the system comprises a first sending module, a second sending module and a third sending module, wherein the first sending module is used for sending a network state reporting request to a mobile communication system under the condition that the combined TSN bridge needs the mobile communication system based on the service information and the historical network state information of a plurality of bridges;

and the second sub-receiving module is used for receiving the current network state information sent by the mobile communication system based on the network state reporting request.

In one embodiment, the network status reporting request includes at least one of the following:

reporting a trigger condition;

reporting the period;

and reporting the information types.

In one embodiment, the electronic device 1300 further comprises:

and the second sending module is used for sending bridge information to each bridge device in the combined TSN bridge, wherein the bridge information comprises information of the combined TSN bridge and TSN scheduling policy information.

In one embodiment, the bridge information further comprises at least one of:

the transmission direction of the joint TSN bridge;

and the TSN service identification information is used for identifying the TSN service flow.

In one embodiment, the electronic device 1300 further comprises:

and the second receiving module is used for receiving the confirmation message sent by each bridge device in the combined TSN bridge based on the bridge information.

scheduling period

Scheduling priority.

In one embodiment, the current network state information includes at least one of:

current network topology information;

current uplink and downlink transmission delay information;

current network load information;

current network coverage;

wherein the service information comprises at least one of the following:

a service transmission characteristic;

transmitting the quality requirement information.

Referring to fig. 14, fig. 14 is a schematic structural diagram of an electronic device according to an embodiment of the present invention, which is a device in a plurality of bridges of a time sensitive network TSN system, it can be understood that the electronic device 1400 is a bridge device in the plurality of bridges, the TSN system further includes a centralized network controller CNC, the plurality of bridges include at least one TSN bridge device and a mobile communication system, as shown in fig. 14, the electronic device 1400 includes:

a first sending module 1401, configured to send current network status information of the electronic device 1400 to the CNC;

a second receiving module 1402, configured to receive CNC service information based on an end device and bridge information sent by current network information of multiple bridges, where the bridge information includes a combined TSN bridge and TSN scheduling policy information, where the combined TSN bridge includes a mobile communication system and N TSN bridge devices in at least one TSN bridge device, N is an integer, and a target bridge device is a network device in the combined TSN bridge;

a scheduling module 1403, configured to perform data scheduling based on the TSN scheduling policy information.

As an example, the bridge information may further include TSN traffic identification information, where the TSN traffic identification information is used to identify TSN traffic streams, and the TSN scheduling policy information may further include scheduling priorities, and the like.

The embodiment of the invention also provides a time sensitive network TSN system, which comprises a centralized network controller CNC and a plurality of bridges, wherein the bridges comprise at least one TSN bridge device and a mobile communication system;

a plurality of network bridges send current network state information to the CNC;

the method comprises the steps that the CNC determines a combined TSN bridge and TSN scheduling strategy information of the combined TSN bridge based on service information sent by end equipment and current network state information of a plurality of bridges, wherein the combined TSN bridge comprises a mobile communication system and N TSN bridge devices in at least one TSN bridge device, and N is an integer;

and the joint TSN bridge schedules data based on the TSN scheduling strategy information.

An embodiment of the present invention further provides an electronic device, including: the processor, the memory and the program stored in the memory and capable of running on the processor, when executed by the processor, implement the processes of the above-mentioned bridge determination method embodiment, and can achieve the same technical effects, and in order to avoid repetition, the details are not described here.

Specifically, referring to fig. 15, an electronic device according to an embodiment of the present invention includes a bus 1501, a transceiver 1502, an antenna 1503, a bus interface 1504, a processor 1505, and a memory 1506.

The electronic equipment is a Centralized Network Controller (CNC) in a Time Sensitive Network (TSN) system, the TSN system further comprises a plurality of bridges, and the plurality of bridges comprise at least one TSN bridge equipment and a mobile communication system;

a transceiver 1502 for receiving current network state information sent by a plurality of bridges;

the processor 1505 is configured to determine a joint TSN bridge and TSN scheduling policy information of the joint TSN bridge based on traffic information sent by an end device and current network state information of a plurality of bridges;

In one embodiment, the transceiver 1502 is further configured to:

under the condition that the joint TSN bridge needs a mobile communication system based on the service information and the historical network state information of the bridges, sending a network state reporting request to the mobile communication system;

reporting a trigger condition;

reporting the period;

and reporting the information types.

In one embodiment, the transceiver 1502 is further configured to:

In one embodiment, the bridge information further comprises at least one of:

the transmission direction of the joint TSN bridge;

In one embodiment, the transceiver 1502 is further configured to:

scheduling period

Scheduling priority.

current network topology information;

current uplink and downlink transmission delay information;

current network load information;

current network coverage;

wherein the service information comprises at least one of the following:

a service transmission characteristic;

transmitting the quality requirement information.

In fig. 15, a bus architecture (represented by bus 1501), bus 1501 may include any number of interconnected buses and bridges, bus 1501 linking together various circuits including one or more processors, represented by processor 1505, and memory, represented by memory 1506. The bus 1501 may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. A bus interface 1504 provides an interface between the bus 1501 and the transceiver 1502. The transceiver 1502 may be one element or a plurality of elements, such as a plurality of receivers and transmitters, providing a means for communicating with various other apparatus over a transmission medium. Data processed by processor 1505 is transmitted over a wireless medium via antenna 1503 and further, antenna 1503 receives the data and forwards the data to processor 1505.

Processor 1505 is responsible for managing the bus 1501 and general processing, and may also provide various functions including timing, peripheral interfaces, voltage regulation, power management, and other control functions. While memory 1506 may be used to store data used by processor 1505 in performing operations.

Alternatively, processor 1505 may be a CPU, ASIC, FPGA or CPLD.

The embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements each process of the bridge determination method in the embodiment, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here. The computer-readable storage medium may be a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk.

An embodiment of the present invention further provides a target network bridge device, including: the processor, the memory and the program stored in the memory and capable of running on the processor, when executed by the processor, implement the processes of the above-mentioned bridge determination method embodiment, and can achieve the same technical effects, and in order to avoid repetition, the details are not described here.

Specifically, referring to fig. 16, an electronic device according to an embodiment of the present invention includes a bus 1601, a transceiver 1602, an antenna 1603, a bus interface 1604, a processor 1605, and a memory 1606.

The electronic device is a device in a plurality of bridges of a Time Sensitive Network (TSN) system, and it can be understood that the electronic device is a bridge device in the plurality of bridges, the TSN system further comprises a Centralized Network Controller (CNC), and the plurality of bridges comprise at least one TSN bridge device and a mobile communication system;

a transceiver 1602 for transmitting current network status information of the electronic device to the CNC;

a transceiver 1602, configured to receive CNC end device-based service information and bridge information sent by current network information of multiple bridges, where the bridge information includes a combined TSN bridge and TSN scheduling policy information, where the combined TSN bridge includes a mobile communication system and N TSN bridge devices in at least one TSN bridge device, N is an integer, and a target bridge device is a network device in the combined TSN bridge;

a processor 1605 for scheduling data based on the TSN scheduling policy information.

The embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements each process of the bridge determination method in the embodiment, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here. The computer readable storage medium is ROM, RAM, magnetic disk or optical disk.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal (such as a mobile phone, a computer, a server, an air conditioner, or a target bridge device) to execute the method according to the embodiments of the present invention.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A bridge determination method for a centralized network controller, CNC, applied to a time sensitive network, TSN, system, the TSN system further comprising a plurality of bridges including at least one TSN bridge device and a mobile communications system, the method comprising:

2. The bridge determination method of claim 1, wherein said receiving current network state information sent by said plurality of bridges comprises:

receiving current network state information sent by the at least one TSN bridge device;

under the condition that the joint TSN bridge needs the mobile communication system based on the service information and the historical network state information of the bridges, sending a network state reporting request to the mobile communication system;

3. The bridge determination method of claim 2, wherein the network status report request includes at least one of:

reporting a trigger condition;

reporting the period;

and reporting the information types.

4. The bridge determination method of claim 1, wherein after determining the joint TSN bridge and the TSN scheduling policy information for the joint TSN bridge, further comprising:

sending bridge information to each bridge device in the joint TSN bridge, wherein the bridge information comprises information of the joint TSN bridge and the TSN scheduling policy information.

5. The bridge determination method of claim 4, wherein the bridge information further comprises at least one of:

a transmission direction of the joint TSN bridge;

TSN service identification information, the TSN service identification information is used to identify TSN service flow.

6. The bridge determination method of claim 4, wherein after sending bridge information to each bridge device in the federated TSN bridge, further comprising:

and receiving confirmation messages sent by each bridge device in the joint TSN bridge based on the bridge information.

7. The bridge determination method of claim 1, wherein the TSN scheduling policy information comprises at least one of:

scheduling period

Scheduling priority.

8. The bridge determination method of claim 1, wherein the current network state information comprises at least one of:

current network topology information;

current uplink and downlink transmission delay information;

current network load information;

current network coverage;

wherein the service information comprises at least one of:

a service transmission characteristic;

transmitting the quality requirement information.

9. A data scheduling method is applied to a target bridge device in a plurality of bridges of a time-sensitive network (TSN) system, wherein the target bridge device is a bridge device in the plurality of bridges, the TSN system further comprises a Centralized Network Controller (CNC), the plurality of bridges comprise at least one TSN bridge device and a mobile communication system, and the method comprises the following steps:

10. The data scheduling method of claim 9 wherein the bridge information further includes a transmission direction of the joint TSN bridge;

and outputting data in the transmission direction of the combined TSN bridge at a target time, wherein the target time is the sum of a first time and a scheduling period in the TSN scheduling policy information, and the first time is the time when the data enters the combined TSN bridge.

11. A data scheduling method is applied to a time-sensitive network TSN system, wherein the TSN system comprises a Centralized Network Controller (CNC) and a plurality of bridges, and the plurality of bridges comprise at least one TSN bridge device and a mobile communication system;

the method comprises the following steps:

the plurality of network bridges send current network state information to the CNC;

12. An electronic device, characterized in that, being a centralized network controller, CNC, in a time sensitive network, TSN, system, the TSN system further comprising a plurality of bridges, the plurality of bridges comprising at least one TSN bridge device and a mobile communication system, the electronic device comprising:

13. An electronic device, being a device in a plurality of bridges of a time sensitive network, TSN, system, the TSN system further comprising a centralized network controller, CNC, the plurality of bridges including at least one TSN bridge device and a mobile communications system, the electronic device comprising:

14. A time sensitive network, TSN, system, the TSN system comprising a centralized network controller, CNC, and a plurality of bridges, the plurality of bridges comprising at least one TSN bridge device and a mobile communications system;

15. An electronic device comprising a transceiver and a processor, the electronic device being a centralized network controller, CNC, in a time sensitive network, TSN, system, the TSN system further comprising a plurality of bridges, the plurality of bridges comprising at least one TSN bridge device and a mobile communications system;

16. An electronic device comprising a transceiver and a processor, the electronic device being a device in a plurality of bridges of a time sensitive network, TSN, system, the TSN system further comprising a centralized network controller, CNC, the plurality of bridges comprising at least one TSN bridge device and a mobile communications system;

17. An electronic device, comprising: processor, memory and program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method according to any one of claims 1 to 8.

18. An electronic device, comprising: processor, memory and program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method according to any one of claims 9 to 10.

19. A computer-readable storage medium, having stored thereon a computer program which, when executed by a processor, carries out the steps of the method of any one of claims 1 to 8; or which computer program, when being executed by a processor, carries out the steps of the method of any one of claims 9 to 10.