CN115378532A

CN115378532A - Message transmission method and device

Info

Publication number: CN115378532A
Application number: CN202110536181.XA
Authority: CN
Inventors: 李汉成
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-05-17
Filing date: 2021-05-17
Publication date: 2022-11-22
Also published as: WO2022242234A1

Abstract

The application provides a message transmission method and a device, wherein the message transmission method comprises the following steps: after receiving the first message, the second node sends the first message and first time information of the first message to the first node, and the first node sends the first message at the first time according to the first time information. The first time information here may be at least one of: the first node sends the first message to the second node according to the first cycle number corresponding to the first message, the first cycle start time corresponding to the first message, the time for the first node to process the first message, the time for the second node to send the first message, and the time for the third node to send the first message. By determining the periodic corresponding relationship between the two nodes and determining the time for the first node to send the first message, the deterministic transmission of the message by the node in the 5GS can be realized when no deterministic transmission mechanism exists between the first node and the second node or when the jitter of the transmission delay is large and the like.

Description

Message transmission method and device

Technical Field

The present application relates to the field of communications, and more particularly, to a method and apparatus for message transmission.

Background

In a fixed network, a time-sensitive network (TSN) is taken as a representative, and a scheme for realizing deterministic transmission is mature. The switching node of the TSN comprises: a Central Network Configuration (CNC) node, a sender (talker) of a message, a receiver (receiver) of a message, and a switch between the talker and the receiver.

To achieve end-to-end deterministic transmission in a network containing a fifth generation system (5 th generation system,5 GS), the 5GS can be modeled as a switching node in the network (e.g., TSN) to achieve the function of a TSN switching node. At present, the deterministic transmission implemented by the 5GS is mainly transmission with a boundary on a delay provided for the periodic service packet, that is, the delay from the entry of the periodic service packet into the 5GS to the transmission from the 5GS is fixed or meets a certain condition. The actual time delay of the 5GS user plane during the transmission of the periodic service packet is uncertain, so how to realize the deterministic transmission of the 5GS is a problem to be solved.

Disclosure of Invention

The application provides a message transmission method and device, which can realize the deterministic transmission of 5GS.

In a first aspect, a method for packet transmission is provided, including: the first node receives a first message from a second node and first time information of the first message, wherein the first time information is used for indicating at least one of the following: a first cycle number corresponding to the first message, a first cycle start time corresponding to the first message, a time for the first node to process the first message, a time for the second node to send the first message, and a time for the third node to send the first message; and the first node sends the first message at the first time according to the first time information.

According to the scheme, the time information of the message is sent to the first node through the second node, the first node determines the time for sending or processing the message according to the time information, and further the time for processing/sending the message can be determined by the first node according to the time information of the message under the conditions that no deterministic transmission mechanism exists between the first node and the second node or the jitter of transmission delay is large and when a large number of messages with different periods and/or arrive at the first node, the message can be processed/forwarded at the correct time, so that the deterministic transmission of the message by the node in 5GS is realized, and meanwhile, the conflict and the packet loss caused by the simultaneous processing of a large number of messages are avoided.

With reference to the first aspect, in certain implementations of the first aspect, the first packet is received by the first node from the second node over a wireless packet service tunneling protocol user plane, GTP-U.

With reference to the first aspect, in some implementation manners of the first aspect, the sending, by the first node, the first packet at the first time according to the first time information includes: the first node determines the first time according to the first time information.

With reference to the first aspect, in certain implementations of the first aspect, when the first time information is used to indicate the first cycle number, the determining, by the first node, the first time according to the first time information includes: the first node determines the first time according to the first cycle number, the cycle length and the first starting time; or, the first node determines the first time according to the first cycle number, the cycle length, a second start time, and a first delay, where the first start time is a reference time for the first node to calculate a time corresponding to the first packet, the second start time is a reference time for the second node to calculate a time corresponding to the first packet, and the first delay is a delay for packet transmission between the first node and the second node.

With reference to the first aspect, in certain implementations of the first aspect, when the first time information is used to indicate the first period start time, the determining, by the first node, the first time according to the first time information includes: when the first period starting time is the period starting time when the second node receives the first message, the first node determines the first time according to the first period starting time and the first time delay.

With reference to the first aspect, in some implementation manners of the first aspect, when the first time information is used to indicate a time when the second node sends the first packet, the determining, by the first node, the first time according to the first time information includes: the first node determines the first time according to the time when the second node sends the first message and the first time delay.

With reference to the first aspect, in certain implementations of the first aspect, the determining, by the first node, the first time according to the first time information includes: the first node receives first indication information from the second node; the first node determines the first time according to the first indication information and the first time information, where the first indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, the second time is a cycle start time corresponding to the cycle number on the first node, or the first indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: the first node sends second indication information to the second node, where the first cycle number or the first cycle start time corresponds to the first node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the first node and second time, the second time is a cycle start time corresponding to the cycle number on the first node, or the first cycle number or the first cycle start time corresponds to the second node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the second node and third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

In the above scheme, the second node may determine the first time information by indicating the period start time corresponding to the first packet on the first node to the second node before the second node sends the first time information to the first node, or indicating the relationship between the period number corresponding to the first node or the second node and the period start time to the second node.

With reference to the first aspect, in certain implementations of the first aspect, when the first time information is used to indicate the first cycle number, the determining, by the first node, the first time according to the first time information includes: the first cycle number is used to indicate that the first packet corresponds to an nth cycle, n is a positive integer, and the first node determines that the first time is a time obtained by adding a jitter time to an earliest arrival time, where the earliest arrival time is an earliest arrival time at the first node among a packet corresponding to the nth cycle and packets in one or more cycles before the nth cycle, and the jitter time is a jitter time of a transmission delay between the first node and the second node.

With reference to the first aspect, in certain implementations of the first aspect, when the first time information is used to indicate the first cycle number, the determining, by the first node, the first time according to the first time information includes: the first cycle number is used to indicate that the first packet corresponds to an nth cycle, n is a positive integer, and the first node determines the latest arrival time of the first packet of the (n + 1) th cycle at the first node.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: the first node receives a second message from a fourth node and second time information of the second message, wherein the first message and the second message belong to the same service; the first node determines the first time according to the first time information and the second time information; the first node sends the second message at the first time.

According to the scheme, when the first node receives a plurality of messages, the time for sending/processing the plurality of messages is determined according to the time information of the plurality of messages, and synchronous transmission after the plurality of messages are combined is achieved.

With reference to the first aspect, in some implementation manners of the first aspect, the sending, by the first node, the first packet at the first time according to the first time information includes: and the first node sends the first message and the first time information to the third node at the first time according to the first time information.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: the first node receiving the first latency from the second node; or, the first node acquires the first time delay configured in advance; or, the first node obtains the first time delay through detection; alternatively, the first node obtains the first delay from a control plane network element.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: the first node receiving the cycle length from the second node; or, the first node obtains the period length configured in advance; alternatively, the first node obtains the cycle length through detection.

In a second aspect, a method for packet transmission is provided, including: the second node receives the first message; the second node sends the first message and first time information of the first message to the first node, wherein the first time information is used for indicating at least one of the following: the first node sends a first message to a second node, wherein the first message comprises a first period number corresponding to the first message, a first period starting time corresponding to the first message, time for processing the first message by the first node, time for sending the first message by the second node, and time for sending the first message by the third node, and the first time information is used for determining the first time for sending the first message.

According to the scheme, the second node sends the time information of the message to the first node, and the second node determines whether the message is sent or processed according to the time information, so that the time for processing/sending the message can be determined by the first node according to the time information of the message when a large number of messages with different periods and/or arrive at the first node under the condition that no deterministic transmission mechanism exists between the first node and the second node or the jitter of transmission delay is large, so that the message can be processed/forwarded at the correct time, the deterministic transmission of the message by the node in 5GS is realized, and meanwhile, the conflict and the packet loss caused by simultaneous processing of a large number of messages are avoided.

With reference to the second aspect, in some implementations of the second aspect, the first packet is sent by the second node to the first node through a wireless packet service tunneling protocol user plane GTP-U.

With reference to the second aspect, in certain implementations of the second aspect, the method further includes: the second node sends to the first node at least one of: the method comprises the steps of cycle length, a first time delay, a first starting time and a second starting time, wherein the first starting time is the reference time for calculating the time corresponding to the first message by the first node, the second starting time is the reference time for calculating the time corresponding to the first message by the second node, and the first time delay is the time delay for transmitting the message between the first node and the second node.

With reference to the second aspect, in certain implementations of the second aspect, the method further includes: the second node sends first indication information to the first node, wherein the first indication information is used for indicating the corresponding relation between the cycle number corresponding to the first node and second time, and the second time is the cycle starting time corresponding to the cycle number on the first node; or, the first indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, where the third time is a cycle start time corresponding to the cycle number on the second node.

With reference to the second aspect, in certain implementations of the second aspect, the method further includes: the second node receiving second indication information from the first node; the second node determines the first time information according to the second indication information, where the first period number corresponds to the first period start time and the first node, the second indication information is used to indicate a correspondence between the period number corresponding to the first node and a second time, the second time is the period start time corresponding to the period number on the first node, or the first period number corresponds to the first period start time and the second node, the second indication information is used to indicate a correspondence between the period number corresponding to the second node and a third time, and the third time is the period start time corresponding to the period number on the second node.

According to the scheme, the second node aligns the period information of the first node and the second node through the information sent by the first node, so that the second node can determine the first time information conveniently.

With reference to the second aspect, in certain implementations of the second aspect, the method further includes: the second node receives the first time information.

In a third aspect, an apparatus for packet transmission is provided, including: a transceiver module, configured to receive a first packet from a second node and first time information of the first packet, where the first time information is used to indicate at least one of: a first cycle number corresponding to the first message, a first cycle start time corresponding to the first message, a time for the first node to process the first message, a time for the second node to send the first message, and a time for the third node to send the first message; the transceiver module is further configured to send the first packet at a first time according to the first time information.

According to the scheme, the time information of the message is sent to the first node through the second node, the first node determines the time for sending or processing the message according to the time information, and then under the condition that no deterministic transmission mechanism exists between the first node and the second node or the jitter of transmission delay is large, when a large number of messages with different periods reach the first node, the first node can determine the time for processing/sending the message according to the time information of the message, so that the message can be processed/forwarded at the correct time, the deterministic transmission of the message by the node in the 5GS is realized, and meanwhile, the conflict and the packet loss caused by simultaneous processing of a large number of messages are avoided.

With reference to the third aspect, in some implementations of the third aspect, the first packet is received by the first node from the second node through a wireless packet service tunneling protocol user plane GTP-U.

With reference to the third aspect, in certain implementations of the third aspect, the apparatus further includes: the first node determines the first time according to the first time information.

With reference to the third aspect, in some implementations of the third aspect, when the first time information is used to indicate the first cycle number, the processing module is specifically configured to: determining the first time according to the first cycle number, the cycle length and the first starting time; or, determining the first time according to the first cycle number, the cycle length, a second start time, and a first time delay, where the first start time is a reference time for calculating a time corresponding to the first packet by the first node, the second start time is a reference time for calculating a time corresponding to the first packet by the second node, and the first time delay is a time delay for transmitting a packet between the first node and the second node.

With reference to the third aspect, in some implementation manners of the third aspect, the processing module is specifically configured to determine the first time according to the first cycle start time and the first time delay, when the first time information is used to indicate the first cycle start time and the first cycle start time is the cycle start time when the second node receives the first packet.

With reference to the third aspect, in some implementation manners of the third aspect, when the first time information is used to indicate a time when the second node sends the first packet, the processing module is specifically configured to: and determining the first time according to the time when the second node sends the first message and the first time delay.

With reference to the third aspect, in certain implementations of the third aspect, the transceiver module is further configured to receive first indication information from the second node; the processing module is specifically configured to determine the first time according to the first indication information and the first time information, where the first indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, the second time is a cycle start time corresponding to the cycle number on the first node, or the first indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

With reference to the third aspect, in some implementations of the third aspect, the transceiver module is further configured to: and sending second indication information to the second node, wherein the first period number or the first period starting time corresponds to the first node, the second indication information is used for indicating a corresponding relationship between the period number corresponding to the first node and second time, the second time is the period starting time corresponding to the period number on the first node, or the first period number or the first period starting time corresponds to the second node, the second indication information is used for indicating a corresponding relationship between the period number corresponding to the second node and third time, and the third time is the period starting time corresponding to the period number on the second node.

With reference to the third aspect, in some implementations of the third aspect, when the first time information is used to indicate the first cycle number, the first cycle number is used to indicate that the first packet corresponds to an nth cycle, where n is a positive integer, the processing module is specifically configured to determine that the first time is a time obtained by adding a jitter time to an earliest arrival time, where the earliest arrival time is an earliest arrival time at the first node in a packet corresponding to the nth cycle and packets in one or more cycles before the nth cycle, and the jitter time is a jitter time of a transmission delay between the first node and the second node.

With reference to the third aspect, in some implementation manners of the third aspect, when the first time information is used to indicate the first cycle number, the first cycle number is used to indicate that the first packet corresponds to an nth cycle, where n is a positive integer, and the processing module is specifically configured to determine a time at which a first packet with the first time being an (n + 1) th cycle arrives at the first node at the latest.

With reference to the third aspect, in some implementation manners of the third aspect, the transceiver module is further configured to receive a second packet from a fourth node and second time information of the second packet, where the first packet and the second packet belong to the same service; the processing module is further configured to determine the first time according to the first time information and the second time information; the transceiver module is further configured to send the second packet at the first time.

With reference to the third aspect, in some implementations of the third aspect, the transceiver module is further configured to: and sending the first message and the first time information to the third node at the first time according to the first time information.

With reference to the third aspect, in certain implementations of the third aspect, the transceiver module is further configured to receive the first delay from the second node; or, the processing module is further configured to obtain the first time delay configured in advance; or, the processing module is further configured to obtain the first time delay through detection; alternatively, the first node obtains the first delay from a control plane network element.

With reference to the third aspect, in some implementations of the third aspect, the transceiver module is further configured to receive the cycle length from the second node; or, the processing module is further configured to obtain the period length configured in advance; or, the processing module is further configured to obtain the cycle length through detection.

In a fourth aspect, an apparatus for packet transmission is provided, including: the receiving and sending module is used for receiving a first message; the transceiver module is further configured to send the first packet and first time information of the first packet to a first node, where the first time information is used to indicate at least one of the following: the first period number corresponding to the first message, the first period starting time corresponding to the first message, the time for the first node to process the first message, the time for the second node to send the first message, and the time for the third node to send the first message, wherein the first time information is used for determining the first time for sending the first message.

With reference to the fourth aspect, in some implementations of the fourth aspect, the first packet is sent by the second node to the first node through a wireless packet service tunneling protocol user plane, GTP-U.

With reference to the fourth aspect, in some implementations of the fourth aspect, the transceiver module is further configured to send, to the first node, at least one of: the first start time is a reference time for calculating the time corresponding to the first message by the first node, the second start time is a reference time for calculating the time corresponding to the first message by the second node, and the first delay is a delay for transmitting the message between the first node and the second node.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the transceiver module is further configured to send first indication information to the first node, where the first indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, and the second time is a cycle start time corresponding to the cycle number on the first node; or the first indication information is used to indicate a corresponding relationship between a cycle number corresponding to the second node and a third time, where the third time is a cycle start time corresponding to the cycle number on the second node.

With reference to the fourth aspect, in some implementations of the fourth aspect, the transceiver module is further configured to receive second indication information from the first node; the device further includes a processing module, where the processing module is further configured to determine the first time information according to the second indication information, where the first cycle number corresponds to the first cycle start time and the first node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, the second time is a cycle start time corresponding to the cycle number on the first node, or, when the first cycle number corresponds to the first cycle start time and the second node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

With reference to the fourth aspect, in certain implementations of the fourth aspect, the method further includes: the transceiver module is further configured to receive the first time information.

In a fifth aspect, a communication apparatus is provided, including: a processor and a memory;

the memory for storing a computer program; the processor is configured to execute the computer program stored in the memory, so as to enable the communication apparatus to perform the communication method and embodiment described in the first aspect or the second aspect.

A sixth aspect provides a computer-readable storage medium having stored therein instructions which, when run on a computer, cause the computer to perform the communication method and embodiments of the first or second aspect.

In a seventh aspect, a chip is provided, which includes: a memory for storing a computer program; a processor for reading and executing the computer program stored in the memory, the processor performing the communication method and embodiments described in the first or second aspect when the computer program is executed.

In an eighth aspect, a computer program product is provided, which comprises computer program code, which, when run on a computer, causes the computer to perform the communication method and embodiments of the first or second aspect.

Drawings

Fig. 1 illustrates a network architecture suitable for use with embodiments of the present application.

Fig. 2 shows a black box architecture of a 5G system implementing deterministic transfer.

Fig. 3 shows a schematic diagram of transmission delay of a downlink message in 5GS.

Fig. 4 shows a scenario in which the period of traffic is less than the transmission delay between nodes.

Fig. 5 is a schematic interaction diagram showing an example of the message transmission method of the present application.

Fig. 6 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 7 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 8 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 9 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 10 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 11 shows an implementation manner of the message transmission method in the application to a 5GS scenario.

Fig. 12 is a schematic interaction diagram showing another example of the message transmission method of the present application.

Fig. 13 shows a scenario of multiflow merging synchronous transmission to which the message transmission method of the present application is applied.

Fig. 14 (a) shows a schematic diagram of the current deterministic transfer mechanism.

Fig. 14 (b) shows a schematic diagram of a 5 GS-adapted deterministic transport network.

Fig. 15 is a schematic block diagram of a communication device for message transmission according to an embodiment of the present application.

Fig. 16 is a schematic diagram of a device 20 for message transmission according to an embodiment of the present disclosure.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

The technical scheme provided by the embodiment of the application can be applied to various communication systems, such as: global system for mobile communications (GSM) systems, code Division Multiple Access (CDMA) systems, wideband Code Division Multiple Access (WCDMA) systems, general Packet Radio Service (GPRS), long Term Evolution (LTE) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD), universal Mobile Telecommunications System (UMTS), universal microwave access (WiMAX) communication systems, fifth generation (5, 5 g) systems, new radio systems (NR), future 3GPP systems, or the like.

Generally, the conventional communication system supports a limited number of connections and is easy to implement, however, with the development of communication technology, the mobile communication system will support not only conventional communication but also, for example, device to device (D2D) communication, machine to machine (M2M) communication, machine Type Communication (MTC), vehicle to anything (V2X) communication (also may be referred to as vehicle network communication), for example, vehicle to vehicle (V2V) communication (also may be referred to as vehicle to vehicle communication), vehicle to infrastructure (V2I) communication (also may be referred to as vehicle to infrastructure communication), vehicle to pedestrian to vehicle (V2P) communication (also may be referred to as vehicle to vehicle communication), and vehicle to network (N2N) communication.

Fig. 1 provides a network architecture, and the following describes each network element that may be involved in the network architecture separately with reference to fig. 1.

1. The UE: as described above in conjunction with fig. 1, the description is omitted for brevity.

2. Access Network (AN): the method provides a network access function for authorized users in a specific area, and can use transmission tunnels with different qualities according to the level of the users, the requirements of services and the like. The access networks may be access networks employing different access technologies. There are two types of current radio access technologies: 3GPP access technologies (e.g., radio access technologies employed in 3G, 4G, or 5G systems) and non-third generation partnership project (non-3 GPP) access technologies. The 3GPP access technology refers to an access technology meeting 3GPP standard specifications, and an access network adopting the 3GPP access technology is referred to as a Radio Access Network (RAN), where an access network device in a 5G system is referred to as a next generation Base station (gNB). The non-3GPP access technology refers to an access technology that does not conform to the 3GPP standard specification, for example, an air interface technology represented by an Access Point (AP) in wifi.

An access network that implements an access network function based on a wireless communication technology may be referred to as a Radio Access Network (RAN). The radio access network can manage radio resources, provide access service for the terminal, and further complete the forwarding of control signals and user data between the terminal and the core network.

The radio access network may be, for example, a base station (NodeB), an evolved NodeB (eNB or eNodeB), a base station (gNB) in a 5G mobile communication system, a base station in a future mobile communication system, or an AP in a WiFi system, and may also be a wireless controller in a Cloud Radio Access Network (CRAN) scenario, or the access network device may be a relay station, an access point, a vehicle-mounted device, a wearable device, and a network device in a future 5G network or a network device in a future evolved PLMN network. The embodiments of the present application do not limit the specific technologies and the specific device forms adopted by the radio access network device.

3. Access and mobility management function (AMF) entity: the present invention is mainly used for mobility management, access management, and the like, and may be used to implement other functions, such as functions of lawful interception, or access authorization (or authentication), and the like, in addition to session management in Mobility Management Entity (MME) functions.

4. Session Management Function (SMF) entity: the method is mainly used for session management, IP address allocation and management of UE, selection of termination points of an interface capable of managing a user plane function, policy control or charging function, downlink data notification and the like.

5. User Plane Function (UPF) entity: i.e. a data plane gateway. Can be used for packet routing and forwarding, or quality of service (QoS) processing of user plane data, etc. The user data can be accessed to a Data Network (DN) through the network element. In the embodiment of the application, the method can be used for realizing the function of the user plane gateway.

6. Data Network (DN): for providing a network for transmitting data. Such as a network of operator services, an Internet network, a third party's service network, etc.

7. Authentication service function (AUSF) entity: the method is mainly used for user authentication and the like.

8. Network open function (NEF) entity: for securely opening services and capabilities, etc. provided by the 3GPP network functions to the outside.

9. The network storage function (NF) entity is used to store the network function entity and the description information of the service provided by the network function entity, and support service discovery, network element entity discovery, etc.

10. Policy Control Function (PCF) entity: a unified policy framework for guiding network behavior, providing policy rule information for control plane function network elements (e.g., AMF, SMF network elements, etc.), and the like.

11. Unified Data Management (UDM) entity: for handling subscriber identity, access authentication, registration, mobility management, etc.

12. Application Function (AF) entity: the method is used for carrying out data routing of application influence, accessing network open function network elements, or carrying out strategy control by interacting with a strategy framework and the like. For example, it may be a V2X application server, a V2X application enabling server, or a drone server (which may include a drone supervision server, or a drone application service server).

In the network architecture shown in fig. 1, the N1 interface is a reference point between the terminal and the AMF entity; the N2 interface is a reference point of the AN and AMF entities, and is used for sending non-access stratum (NAS) messages and the like; the N3 interface is a reference point between the (R) AN and the UPF entity and is used for transmitting data of a user plane and the like; the N4 interface is a reference point between the SMF entity and the UPF entity and is used for transmitting information such as tunnel identification information, data cache indication information and downlink data notification information of the N3 connection; the N6 interface is a reference point between the UPF entity and the DN, and is used for transmitting data of a user plane and the like.

It should be understood that the network architecture shown in fig. 1 may be applied to the embodiment of the present application, and the network architecture to which the embodiment of the present application is applied is not limited to this, and any network architecture that can implement the functions of the foregoing network elements is applied to the embodiment of the present application.

It should also be understood that the AMF entity, SMF entity, UPF entity, NEF entity, AUSF entity, NRF entity, PCF entity, UDM entity shown in fig. 1 may be understood as network elements in the core network for implementing different functions, e.g. may be combined into network slices as required. The core network elements may be independent devices, or may be integrated in the same device to implement different functions, which is not limited in this application. It should be noted that the "network element" may also be referred to as an entity, a device, an apparatus, a module, or the like, and the application is not particularly limited.

It should also be understood that the above-mentioned names are only used for distinguishing different functions, and do not represent that these network elements are respectively independent physical devices, and the present application is not limited to the specific form of the above-mentioned network elements, for example, the network elements may be integrated in the same physical device, or may be respectively different physical devices. Furthermore, the above nomenclature is only used to distinguish between different functions, and should not be construed as limiting the application in any way, and this application does not exclude the possibility of other nomenclature being used in 5G networks and other networks in the future. For example, in a 6G network, some or all of the above network elements may follow the terminology in 5G, and may also adopt other names, etc. The description is unified here, and will not be described below.

It should also be understood that the name of the interface between each network element in fig. 1 is only an example, and the name of the interface in the specific implementation may be other names, which is not specifically limited in this application. In addition, the name of the transmitted message (or signaling) between the network elements is only an example, and the function of the message itself is not limited in any way.

As shown in fig. 2, the 5GS is modeled as a switching node (hereinafter referred to as 5GS switching node) in a network (e.g., a TSN network) that implements the functionality of the TSN switching node to achieve end-to-end deterministic transmission in a network comprising a 5G system. The AF adapts the information of the 5GS to the information of the TSN network switching node, interacts with a controller in the TSN network, and sends the information sent by the TSN controller to a 5G core network (5G core, 5GC) in a 5GS mode (5 GS control plane). The user-side TSN converter (DS-TT) and the network-side TSN converter (NW-TT) are logic functions of a 5GS user plane and are used for realizing user plane characteristics of the TSN switching node, such as topology discovery and scheduling rules for realizing TSN control plane creation. DS-TT can also be described as TSN Translator (device), and can be deployed together with UE or deployed independently; the NW-TT can also be described as TSN Translator (UP), and can be deployed together with UPF or deployed independently. For convenience of description, the two logic functions are respectively disposed in combination with the UE and the UPF, but the present application is not limited thereto. In addition, 201 in the figure may be understood as a data packet, or a message, or may also be in other data transmission forms, which is not limited in this application. At this point, only one packet is transmitted in the 5GS switching node during the cycle.

The deterministic transmission provided by the 5GS is a transmission with a boundary on the delay provided by the periodic service message, that is, the delay of the service message from entering the 5GS (for example, for the downstream, the message arrives at the UPF/NW-TT) to being sent out from the 5GS (for example, for the downstream, the message is sent out from the UE/DS-TT) is fixed or is required to be greater than a certain minimum delay t1 and less than a certain maximum delay t2. To achieve the above capability, the current 5GS adopts the following mechanism:

1.5GS can get the period of the message, and the time to reach 5GS (arrival time) and/or the time from 5GS (arrival time) in each period.

2.5GS user plane can provide maximum latency guaranteed transmission (UPF/NW-TT to UE/DS-TT), and assume latency is 5GS transmission latency (5 GS bridge delay); each segment of the 5GS user plane can guarantee the maximum time delay, and the method comprises the following steps: (1) The maximum delay between the UPF/NW-TT and the RAN may be referred to as a core network packet delay budget (CN PDB); (2) The maximum delay between the RAN and the UE may be referred to as 5G access network packet delay budget (5G access network packet delay budget,5G-AN PDB), (3) the delay between the UE and the DS-TT may be referred to as UE-DS-TT residual time (UE-DS-TT dwell).

3.5GS can calculate the time for assisting RAN scheduling from the arrival time (arrival time) and/or the transmission time (arrival time) in combination with the delay of each segment in 2: an arrival time in Time Sensitive Communication Assistance Information (TSCAI). For example, for a downlink, if an arrival time of a packet at the UPF is obtained, the arrival time in the TSCAI is a time of the packet arriving at the RAN, and is specifically calculated as arrival time + CN PDB; for the uplink, if the arrival time of the message at the UE is obtained, the arrival time in the TSCAI is the time when the message is sent from the UE to the RAN, and is specifically calculated as arrival time + UE-DS-TT residual time.

The above parameters and calculation methods are only exemplary, and are not limited to the definition and calculation methods of other methods.

After determining the above information, for example, for downstream, the method for implementing deterministic transmission by 5GS includes:

1, after receiving a downlink message, the UPF encapsulates the message by using a GTP-U protocol, and sends the message to the RAN through a QoS flow of a session corresponding to a data flow;

and 2, after receiving the message, the RAN can forward the message according to the information in the TSCAI. For example, after reaching the arrival time in the TSCAI, the message is forwarded to the UE through the air interface;

and 3, after receiving the message, the UE/DS-TT sends or processes the message at the time specified by the messages time.

It can be seen from the above process that the 5GS is implemented by buffering the message arriving in advance to the time window calculated according to the maximum transmission delay by ensuring the maximum delay of forwarding, so that the message looks like passing a fixed transmission delay each time (i.e. the maximum 5GS delay) when passing the 5GS transmission.

Currently, when a 5GS user plane transmits a packet, actual time delay is uncertain, for example, a multi-hop forwarding device passes between a UPF and a RAN, or due to uncertainty of processing time delay inside the UPF, packets of the same service in different periods may reach the RAN through different time delays.

Fig. 3 shows a schematic diagram of transmission delay of a downlink message in 5GS. As shown in fig. 3, for the downstream example, it is assumed that the maximum delay inside the UPF is 0.1ms, and the minimum and maximum transmission delays between the UPF and the RAN are 1ms and 3ms, respectively, i.e., the delay from the UPF to the RAN (corresponding to the above-mentioned CN PDB) has a minimum value dmin of 1.1ms and a maximum value dmax of 3.1ms. Assuming that the time of the data stream arriving at UPF in the period k is t1, and the time of arriving at UPF in the period k +1 is t2, then correspondingly, the time of the packet arriving at RAN in the period k belongs to [ t1+ dmin, t1+ dmax ], and similarly, the time of the packet arriving at RAN in the period k +1 belongs to [ t2+ dmin, t2+ dmax ].

If the RAN transmits the message based on the time of the message reaching the RAN, the RAN is required to distinguish the period of the message when receiving the message. It should be noted that the time that the message in the period k reaches the RAN after the maximum delay dmax should be earlier than the time that the message in the period k +1 reaches the RAN after the minimum delay dmin, so that the time limit is only available when the message in different periods reaches the RAN, and the RAN distinguishes the messages in different periods according to the time limit. Namely, the requirements are met: t1+ dmax < t2+ dmin, after finishing: t2-t1> dmax-dmin, wherein t2-t1 is the service period, and dmax-dmin is the jitter of the transmission message between the UPF and the RAN. It can therefore be considered that: to implement the method for determining transmission based on the maximum delay buffer message, it must be limited: the period of the traffic needs to be larger than the jitter of the transmission delay between the nodes.

The following describes a scenario that does not satisfy the above-described restriction conditions with reference to fig. 4. Fig. 4 shows a scenario where the period of traffic is less than the transmission delay between nodes.

As shown in fig. 4 (a), it is assumed that the period of the service is 1ms, a packet with a period k (S401) arrives at the UPF in the 0 th ms, t1=0ms corresponds to the packet with the period k, a packet with a period k +1 (S402) arrives at the UPF in the 1 st ms, and t1=1ms corresponds to the packet with the period k + 1. Based on the scenario in fig. 4 (a), the arrival times of the messages with different periods in the TSCAI of the RAN are calculated according to the existing calculation method. As shown in fig. 4 (b), the arrival time of the message with the period k in the TSCAI of the RAN is 3.1ms, and the arrival time of the message with the period k +1 in the TSCAI of the RAN is 4.1ms. Actually, as shown in (c) of fig. 4, the time for the message with the period k to reach the RAN is between 1.1ms and 3.1ms (the dashed box shown in S403), and the time for the message with the period k +1 to reach the RAN is between 2.1ms and 4.1ms (the dashed box shown in S404). If the message with the period k +1 arrives at the RAN before the 3.1ms, for example, it appears that the messages with the period k and the period k +1 arrive at the RAN between 2.1ms and 3.1ms as shown in (c) in fig. 4, even if the message with the period k +1 may arrive at the RAN earlier than the message with the period k, the RAN cannot distinguish whether the arriving message belongs to the period k or the period k +1, and thus cannot process the message with the corresponding period at the correct time.

It should be noted that the description of the arrival of the message at the arrival time of the RAN is based on a scenario, and at present, the arrival time of the message provided to the RAN may be described in a cycle and a time within the cycle, for example, the cycle is 1ms, the arrival time is 0.1ms, that is, the 0.1ms time within each 1ms cycle, rather than indicating the time within each cycle.

Therefore, in order to implement deterministic transmission of the 5GS, when there are different periods and/or a large number of packets arriving at nodes in the 5GS when deterministic transmission is not supported between the nodes or when jitter of transmission delay is greater than or equal to a service period, the node needs to forward/process the packets at a correct time.

The method 500 for message transmission according to the present application is described in detail below with reference to fig. 5. The first node and the second node in fig. 5 are both network elements in a 5GS. Illustratively, the first message enters the 5GS from the second node or the second node receives the first message from other network elements in the 5GS, and the 5GS sends the first message from the first node or the first node sends the first message received from the second node to the next network element in the 5GS.

S501, the second node receives the first message.

As an example, the second node may receive the first packet from a control plane network element (e.g., SMF).

S502, the second node sends the first message and the first time information of the first message to the first node. Correspondingly, the first node receives a first message from the second node and first time information of the first message.

The first time information here is used to indicate at least one of: a first cycle number corresponding to the first message, a first cycle start time corresponding to the first message, a time for the first node to process the first message, a time for the second node to send the first message, and a time for the third node to send the first message. It should be understood that, in the embodiment of the present application, the messages received, forwarded, or processed by the first node and the second node are both periodic messages or are shaped into periodic messages, the first message is a message corresponding to the first period in the above periodic messages, and there may be a plurality of messages corresponding to the first period, and the first message is one of the plurality of messages.

For ease of explanation of the method 500, the contents of the first time information indication will be explained below. For example, the first time information is used to indicate one of:

(1) The first cycle number corresponding to the first message: for example, the first packet may be understood as the packet S401 of the k-th cycle in fig. 4, and the number of the first cycle corresponding to the first packet may be understood as k corresponding to S401 in fig. 4.

(2) The first period starting time corresponding to the first message: the first period start time corresponding to the first packet, that is, the start time of the first period, where the start time may be the start time of the second node receiving, forwarding, or processing the packet of the first period, or may be understood as the time of the second node receiving, forwarding, or processing the first packet in the first period.

(3) The time for the first node to process the first packet: the time when the first node processes/forwards the packet corresponding to the first period, for example, when the first node is the RAN in fig. 3, the time when the first node processes the first packet may be understood as the time when the RAN forwards the first packet to the UE, or may be understood as the time when the packet arrives at the RAN (similar to the packet arrival time in TSCAI described above).

(4) The time when the second node sends the first message: it may be the time when the second node receives or processes or transmits the first packet, for example, it may be understood that t1=0ms corresponds to the packet S401 with the period k in (a) in fig. 4.

(5) The time for the third node to send the first message: it may be the time that the third node receives or processes or transmits the first packet. It should be understood that, when the second node sends the first packet to the first node, the second node carries the time for the third node to send the first packet, and the first node may determine a local forwarding policy (including the time for the first node to forward the packet) according to the time for the third node to send the first packet, and then when the first node sends the first packet to the third node, the first node carries the time for the third node to send the first packet. Specifically, the first node may directly send the first packet to the third node, and may also send the first packet to the third node through other network elements, and when sending the first packet to the third node, the other devices herein also need to carry time for the third node to send the first packet. Exemplarily, as shown in fig. 3, when the second node is a UPF, the first node is a RAN, and the third node is a UE, time information carried in a first message sent by the UPF to the RAN is time for the UE to send the first message, and at this time, the first node directly sends the first message to the third node. Exemplarily, when the second node is a network element in the 5GS except the network element in fig. 3, the first node is a UPF, the third node is a UE, and the UPF sends the first packet to the UE through the RAN. The time information of the first message received by the UPF from other nodes is the time when the UE sends the first message. And the UPF sends the first message and the time for the third node to send the first message to the UE through the RAN.

It should be appreciated that the first packet may be received by the first node from the second node over a wireless packet service tunneling protocol user plane, GTP-U, when the first node is a RAN and the second node is a UPF, or when the first node is a UPF and the second node is a RAN.

It should be understood that the first message and the first time information may be sent by the second node to the first node, respectively, or the first message may include the first time information, which is not limited in this application.

S503, the first node sends the first packet at a first time according to the first time information.

Exemplarily, S503 may include: the first node determines the first time according to the first time information.

How the first node determines the first time will be described below according to the difference of the first time information indicating content.

In a possible case, the first time information is used to indicate a first cycle number corresponding to the first packet.

In a first mode, the first node determines the first time according to the first cycle number, the cycle length and the first start time; the first start time is a reference time for the first node to calculate a time corresponding to the first packet, or the first start time may also be a start time of an mth cycle on the first node, where the mth cycle may or may not correspond to the first packet, and M is a positive integer.

(1) The first starting time is a reference time for the first node to calculate the time corresponding to the first message:

it should be understood that the reference time of the time corresponding to the first packet calculated by the first node may be understood as the starting point of the time corresponding to the first packet on the first node. For example, the period length is 1ms, the reference time t1 of the time corresponding to the first packet calculated by the first node is 1 point of a certain day, the period number corresponding to the first packet is k, and the first period is zero k ms at the starting time =1 point of the first node.

The time corresponding to the first packet includes the starting time of the first period corresponding to the first packet at the first node, i.e., the first time. In this case, the first time satisfies the following equation:

first time = first start time + first cycle number × cycle length.

(2) The first start time may also be the start time of the mth cycle on the first node:

it should be understood that the second node sends the periodic message to the first node, and the first message is the first periodic message in the periodic message. The first period may or may not be the mth period. When the first period is the mth period, the implementation is the same as the following possible case three. When the first period is not the mth period, the manner in which the first node determines the first time includes at least the following two. For example, the start time of the mth cycle is cycle _ M, the cycle number corresponding to the first packet is k, and the cycle length is cycle.

As an example, the first node calculates a reference time t1= cycle _ M-cycle × M of a cycle corresponding to the periodic packet at the start time of the first node. The first node then calculates, first time = t1+ cycle × k.

As another example, the first node calculates a first time = cycle _ M + (k-M) cycle.

In a second mode, the first node determines the first time according to the first cycle number, the cycle length, a second start time, and a first time delay, where the second start time is a reference time for the second node to calculate a time corresponding to the first packet, or the second start time may be a start time of an nth cycle on the second node, where the nth cycle may correspond to the first packet or may not correspond to the first packet, and N is a positive integer. The first delay is a delay of a message transmitted between the first node and the second node.

It should be noted that, in the present application, a delay of transmitting a packet between a first node and a second node may be a maximum delay, an average delay, or a fixed delay (for example, when a deterministic transmission network is deployed between the first node and the second node, the delay may be fixed).

(1) The second starting time is a reference time for calculating the time corresponding to the first message by the second node.

It should be understood that the reference time of the time corresponding to the first packet calculated by the second node may be understood as the starting point of the time corresponding to the first packet on the second node. For example, the period length is 1ms, the reference time t2 of the time corresponding to the first packet calculated by the second node is 1 point of yesterday, the maximum delay is 5ms, and the first period number is k, then the reference time t1 of the time corresponding to the first packet calculated by the first node is one point and zero 5ms of yesterday, and the first period is zero (k + 5) ms at the starting time =1 point and zero (k + 5) ms at the first node.

The time corresponding to the first packet includes an initial time, i.e., a first time, of a first period corresponding to the first packet at the first node. In such a case, the first time satisfies the following equation:

first time = (second start time + first delay) + first cycle number × cycle length.

(2) The second start time is the start time of the nth period on the second node.

It should be understood that the second node sends periodic messages to the first node, and the first message is a first periodic message in the periodic messages. The first period may be the nth period or may not be the nth period. When the first period is the nth period, the implementation is the same as the following possible case two. When the first period is not the nth period, the manner of determining the first time by the first node includes at least the following two manners. For example, the start time of the nth cycle is cycle _ N, the cycle length is cycle, the cycle number corresponding to the first packet is k, and the first delay is x ms.

As an example, the first node calculates a reference time t2= cycle _ N-cycle × M of a cycle corresponding to the periodic packet at the start time of the second node. The first node then calculates the first time = (t 2+ x) + cycles × k.

As another example, the first node calculates the first time = cycle _ N + (k-N) cycle + x.

The first node determines that the first time is a time obtained by adding a jitter time to an earliest arrival time, where the earliest arrival time is the earliest arrival time at the first node in a packet corresponding to the nth period and packets in one or more periods before the nth period, and the jitter time is a jitter time of a transmission delay between the first node and the second node.

As an example, the earliest arrival time here may be obtained by detection.

As an example, if the cycle lengths of the first node and the second node are not equal, the first node further needs to determine the cycle length through detection in the third method, which is specifically referred to as the possible case two of S705 in the method 700, and details are not repeated here.

In a fourth mode, the first cycle number is used to indicate that the first packet corresponds to an nth cycle, n is a positive integer, and the first node determines the latest arrival time of the first packet in the (n + 1) th cycle at the first time.

As an example, the latest arrival time of the first packet at the first node may be obtained by detection.

It should be noted that the first and second manners are applicable to a scenario in which clocks of the first and second nodes are synchronized, and the third and fourth manners are applicable to a scenario in which clocks of the first and second nodes are synchronized or not synchronized. In addition, for the scenario where the clocks are not synchronized as mentioned in the present application, the first and second ways may also be applicable if the clock skew of the clocks of the two nodes can be obtained.

In a possible case two, the first time information is used to indicate a first period start time corresponding to the first packet.

When the first period starting time is the period starting time when the second node receives the first message, the first node determines the first time according to the first period starting time and the first time delay.

For example, the first time delay between the first node and the second node is 5ms, the start time of the first period corresponding to the first packet at the second node is 3 o 'clock, and the start time of the first period corresponding to the first packet at the first node is 3 o' clock and 5ms.

In this case, the first time satisfies the following formula:

first time = first cycle start time + first time delay.

In a possible case three, the first time information is used to indicate a time for the first node to process the first packet.

It should be noted that, in the present application, the "time for the first node to process the first packet" may also be time for the first node to send the first packet or time for the first node to receive the first packet.

It should be understood that the time when the first node processes the first packet herein may be an instruction to the first node to process the first packet at that time; or, the first node may be instructed to process the first packet at the first time after determining the forwarding policy according to the time, for example, the first time may be before the time, specifically, the first node may forward the first packet to the third node after receiving the first packet, and the time is the time for the third node to process the first packet, so the first time determined by the first node needs to be before the time, which is not limited in this application.

It should be understood that the time may be obtained by the second node according to the cycle start time and the first time delay calculation corresponding to the first packet on the second node. Alternatively, the time for the first node to process the first packet may be obtained by the second node according to a correspondence relationship between a period of the first node and a period of the second node, which is obtained in advance.

In a possible case, the first time information is used to indicate a time when the second node sends the first packet.

It should be noted that "the time when the second node sends the first packet" mentioned in this application may also be the time when the second node processes the first packet, and for convenience, this application only takes "the time when the second node sends the first packet" as an example, but this is not limited thereto.

The first node determines the first time according to the time when the second node sends the first message and the first time delay.

In this case, the first time satisfies the following formula:

the first time = the time when the second node sends the first packet + the first delay.

In a possible case five, the first time information is used to indicate the time for the third node to send the first packet.

And the first node sends the first message and the first time information to the third node at the first time according to the first time information.

It should be understood that the first node is not a node of the switching node (which may be, for example, a 5 GS) that sends the first packet out, but is a network element of the switching node, and the third node is a node of the switching node that sends the first packet out. Alternatively, the first node and the third node are both a network element in a switching node.

As an example, when the UPF is the second node, the RAN is the first node, and the RAN forwards the packet, the first time information may be a time when the UE sends the packet, and the RAN determines whether the RAN should preferentially forward the packet according to an expected time when the UE sends the packet, that is, determines the first time.

For example, the case of the RAN2 in the method 900 may be specifically referred to, and details are not repeated here.

A sixth possible case where the first node determines the first time according to the first time information, includes:

the first node receives first indication information from the second node;

the first node determines the first time according to the first indication information and the first time information.

It should be understood that, in combination with the above-mentioned possible cases one to five, the purpose of the first indication information is to make the first node determine the correspondence between the period of the first node and the period of the second node, so that the first node determines the first time according to the correspondence and the first time information.

As an example, the first indication information is used to indicate a correspondence relationship between a cycle number corresponding to the first node and a second time, where the second time is a cycle start time corresponding to the cycle number on the first node.

As an example, the first indication information is used to indicate a correspondence relationship between a cycle number corresponding to the second node and a third time, where the third time is a cycle start time corresponding to the cycle number on the second node, where the first node may determine the cycle start time corresponding to the cycle number on the first node according to the third time and a time delay between the first node and the second node, where the time delay between the first node and the second node may be preconfigured on the first node or obtained by the first node from a control plane network element.

It should be noted that the first indication information may be sent by the second node to the first node together with the first time information, or may be sent before or after the first time information, which is not limited in this application.

According to the embodiment of the application, the second node sends the time information of the message to the first node, and the first node determines the time for sending or processing the message according to the time information, so that the deterministic transmission of the message by the node in the 5GS can be realized when no deterministic transmission mechanism exists between the first node and the second node or the transmission delay has large jitter and other scenes. When different periods or a large number of messages reach the first node, the first node can determine the forwarding time of the messages according to the time information, and delay forwarding is performed on the messages which do not need to be forwarded at present, so that collision and packet loss caused by simultaneous processing of a large number of messages are avoided. Of course, the embodiments of the present application can also be applied to other scenarios, for example, a scenario in which the jitter of the transmission delay is smaller than the period of the service.

Optionally, the method further comprises:

s504, the first node sends second indication information to the second node, where the second indication information is used to send the cycle start time corresponding to the first packet on the first node to the second node, or is used to indicate a relationship between the cycle number corresponding to the first node or the second node and the cycle start time to the second node, so that the second node determines the first time information.

As an example, when a first cycle number or the first cycle start time in first time information corresponds to the first node, the second indication information is used to indicate a correspondence between the cycle number corresponding to the first node and a second time, which is the cycle start time corresponding to the cycle number on the first node; or, when the first period number or the first period start time in the first time information corresponds to the second node, the second indication information is used to indicate a correspondence between the period number corresponding to the second node and a third time, where the third time is the period start time corresponding to the period number on the second node.

In the embodiment of the application, the second node may determine the first time information by indicating the period start time corresponding to the first packet on the first node to the second node before the second node sends the first time information to the first node, or indicating the relationship between the period number corresponding to the first node or the second node and the period start time to the second node.

Optionally, the method further comprises:

the first node receives a second message from a fourth node and second time information of the second message, wherein the first message and the second message belong to the same service; the first node determines the first time according to the first time information and the second time information; the first node sends the second message at the first time.

As an example, the above scheme is applicable to the scenario of multi-stream combining synchronous transmission shown in fig. 13, which will be further described in conjunction with fig. 13 later.

According to the embodiment of the application, when the first node receives a plurality of messages, the time for sending/processing the plurality of messages is determined according to the time information of the plurality of messages, and synchronous transmission after the plurality of messages are combined is achieved.

It should be noted that, in the present application, the first node may obtain the first delay through various ways, and exemplarily, the first node receives the first delay from the second node; or, the first node acquires the first time delay configured in advance; or, the first node obtains the first time delay through detection; alternatively, the first node obtains the first delay from a control plane network element (e.g., SMF), which is not limited in this application.

It should be noted that, in the present application, the second node may obtain the first delay through various ways, and exemplarily, the second node receives the first delay from the first node; or, the second node obtains the first time delay configured in advance; or the second node obtains the first time delay through detection; or the second node is obtained from a control plane network element (e.g., SMF), which is not limited in this application.

It should be noted that, in the present application, the first node may obtain the period length in multiple ways, and exemplarily, the first node receives the period length from the second node; or, the first node obtains the period length configured in advance; alternatively, the first node obtains the period length through detection, which is not limited in this application.

The method 500 for message transmission according to the present application is described above with reference to fig. 5.

With reference to fig. 6 to fig. 10, the method for packet transmission according to the present application is described in detail below with respect to a scenario where a first node and a second node are clock-synchronized and clock-unsynchronized, respectively.

The following describes the method 600 for packet transmission in the clock synchronization scenario according to the embodiment of the present application in detail with reference to fig. 6 to 9.

As shown in fig. 6 (a), when the first node communicates with the second node in the 5GS, one or more nodes may pass between the first node and the second node, and each node has internal processing delay and also has transmission delay between nodes. The maximum delay between the first node and the second node in the figure is the sum of the internal processing delay of each node and the maximum value of the transmission delay between the nodes, and the delays in the methods 610 to 630 can be understood as the maximum delay here. Because the clocks between the first node and the second node are synchronous, after the time information between the first node and the second node is aligned, the time for processing or forwarding the message by the first node can be determined according to the time for the message to reach the second node.

It should be noted that, with regard to understanding the clock synchronization scenario: if the first node and the second node are not synchronized in time, but clock skew of clocks of the two nodes can be obtained, the clock synchronization can be performed. For example, the first node is a RAN, the second node is a UPF, the RAN operates based on clock 1, the UPF operates based on clock 2, and the UPF is capable of obtaining offsets for clock 1 and clock 2, including frequency offsets and/or time offsets. Taking the uplink flow sent by the RAN to the UPF as an example, and the cycle length on the RAN is cycle1, the UPF may obtain cycle length cycle2 on the UPF according to the frequency offset, and then the RAN and the UPF may obtain the time and/or related parameters for processing the packet based on the respective cycle lengths in combination with the cycle numbers. For determining the processing time parameters, for example, the time offset and the frequency offset of the RAN and the UPF can be obtained, that is, the corresponding time parameters on the RAN and/or the UPF can be determined by calculation in combination with the offset information.

In the present application, the arrival time t1 is a time when the packet arrives at the 5GS entry (for example, when the second node is the entry when the packet arrives at the 5GS, the second start time in the method 500), and the transmission time t2 is a time when the packet is sent to the neighbor device or the application by the 5GS (for example, when the packet is sent from the first node to the neighbor device or the application by the 5GS, the first start time in the method 500). Taking the downlink as shown in fig. 6 as an example, the arrival time is the time when the packet arrives at the UPF, and the transmission time is the time when the RAN processes the packet or the time when the packet arrives at the RAN, or the time when the UE sends the packet to the neighboring device or application. In the uplink flow, the arrival time is the time when the packet arrives at the UE or the time when the packet is sent from the UE to another device inside the RAN or 5GS, and the sending time is the time when the packet arrives at or sends from the UPF.

It should be noted that, in the embodiment of the present application, the "arrival time" and the "sending time" are taken as examples for description, and in the implementation process of the method for packet transmission in the present application, the "arrival time" and the "sending time" may also be processing times in other forms in the node, which is not limited in the present application.

It should be understood that, in this embodiment, t1 may be understood as a reference time for the first node in the method 500 to calculate the time corresponding to the first packet, and t2 may be understood as a reference time for the second node in the method 500 to calculate the time corresponding to the first packet.

Next, referring to fig. 7, fig. 8, and fig. 9, a method 610, 620, and 630 for message transmission in the present application are respectively described by taking downlink as an example. It should be noted that, in the methods 610, 620, and 630, in order to distinguish the "sending time" corresponding to different network elements, t2a and t2b are used to replace t2 for explanation.

Fig. 7 is a schematic interaction diagram of a method 610 of message transmission of the present application. The method 610 is illustrated in downlink, where the first node includes a RAN and/or a UE and the second node is a UPF. The method 610 mainly describes in detail a first possible case, a second possible case, a third possible case, and a fourth possible case in S503 of the method 500.

S611, the SMF determines the cycle length, the arrival time t1 and the sending time t2 of the message.

It should be understood that the SMF determines the above information from information provided by an external device or network element interacting with the 5GS (e.g., subscription information of the network element) sent by the AF.

S612, the SMF configures the message period length and t1 to the UPF.

For example, the SMF configures the message period length and t1 to the UPF through a session creation/modification request.

As an example, the cycle length of the service packet is 1ms, the arrival time of the packet in the cycle is 0.1ms, and the 0.1ms in each 1ms cycle is the arrival time of the packet. Or, if the arrival time is the designated time t1 and the period length is 1ms, timing is started from t1, and the arrival time of the message is a period every 1ms.

S613 is implemented in various ways, such as S613a and/or S613b below.

S613a, the SMF configures the cycle length of the message to the RAN and the time t2a for the message to reach the RAN through session creation; or, S613b, the SMF configures the period length of the message and the time t2b when the message is sent from the UE to the UE.

As a possible case, when the RAN is the first node, the SMF performs S613a, where the configured information is used for S617a to determine the time t3 for the RAN to forward the first packet.

In a possible case two, when the UE is the first node, the SMF performs S613b, where the configured information is used for S617b to determine the time t4 for the UE to forward the first packet.

Third, when the first node includes a RAN and a UE, the SMF performs S613a and S613b, where the configured information is used for the time t3 when the RAN determines to forward the first packet in S617a and the time t4 when the UE determines to forward the first packet in S617b, respectively.

S614, the UPF receives the first message at the time t.

S615 may be implemented in various ways, such as S615a or S615b below.

S615a, the UPF calculates the cycle number of the first message, adopts GTP-U to package the first message, and packages the calculated cycle number k in a GTP-U packet header.

As to the number of the reception cycle, for example, the number of cycles elapsed at time t in S604, specifically, (t-t 1)/cycle, is calculated as the cycle number, with t1 as the starting point, as the starting time of cycle 0 (not limited to cycle 0, but may be any cycle number), where cycle is the message cycle length.

It should be understood that when the clocks of the first node and the second node are synchronized, the corresponding cycle numbers of the messages in the same cycle on the first node and the second node are identical. Thus, for the case where the first node comprises a RAN and/or a UE, the cycle numbers communicated between the first node and the second node are both k.

Due to the difference between the UPF and the RAN, between the UPF and the UE, and between the RAN and the UE, and according to the difference between the first node and the specific network element, the method for transmitting the cycle number in the embodiment of the present application may be different.

Specifically, corresponding to the possible case one in S613, the UPF in S616 sends the cycle number to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11.

Corresponding to the second possible case in S613, (1) the UPF sends the cycle number to the UE through a protocol layer between the UPF and the UE, where the RAN is required to forward, and the RAN does not perceive the cycle number, and in this embodiment of the present application, the cycle number may be sent through S616 and S618, specifically, see mode 3 in fig. 11; or, (2) in S616, the UPF sends the cycle number to the RAN through the GTP-U layer, and in S618, the RAN communicates the cycle number to the UE through a protocol layer between the UE and the RAN, which may be specifically referred to as mode 2 in fig. 11. It should be understood that in (2), the RAN may or may not be aware of the cycle number, but the RAN will not process the cycle number regardless of whether the RAN is aware of the cycle number.

Corresponding to the possible case three in S613, in S616, the UPF sends the cycle number to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11; the UPF sends the cycle number to the UE through a protocol layer between the UPF and the UE, where the RAN is required to forward, and the RAN cannot perceive the cycle number, and in this embodiment of the present application, the cycle number may be sent through S616 and S618, which may be specifically referred to as manner 3 in fig. 11.

S615b, adopting GTP-U to package the first message, and packaging the initial time of the period corresponding to the first message in a GTP-U packet header. The starting time of the period corresponding to the first packet may be the starting time of the period corresponding to the first packet at the UPF, or the starting time of the period corresponding to the first packet at the RAN/UE.

The following describes the start time of the corresponding period of the first packet with reference to (b) in fig. 6. The UPF sends messages of a plurality of periods to the RAN/UE, wherein the messages of the k period comprise the messages of the k period, and the messages of the k period comprise the first messages. As shown in fig. 6 (b), two time axes are time for transmitting/processing the packet by the UPF and time for transmitting or processing the packet by the RAN/UE, respectively, time occupied on the time axis by the block corresponding to S642 is the kth period corresponding to the first packet, all packets in the block are packets corresponding to the kth period, time occupied on the time axis by the block corresponding to S643 is the k +1 th period, and all packets in the block correspond to the period. S641 is a first packet, and the period start time corresponding to the first packet is the start time of the kth period (S642) on two time axes. It should be noted that, the period start time corresponding to the first message herein may be the earliest time of arrival of the first message in the k-th period, or the earliest time of arrival of the first message in the k-th period may also have some offset with respect to the period start time corresponding to the first message, the start point of the period start time of each period on the time axis is fixed, and the earliest time of arrival of the first message in each period is not necessarily fixed, for example, in (b) in fig. 6, there may be an interval between the period start time corresponding to the first message and the first message in S642 on the time axis.

In a first possible implementation manner, the starting time of the period corresponding to the first packet is the starting time of the period corresponding to the first packet at the UPF.

It should be understood that for the case where the first node includes a RAN and/or a UE, the start time of the period corresponding to the first packet communicated between the first node and the second node is the start time of the period corresponding to the first packet at the UPF.

Due to the difference between the UPF and the RAN, between the UPF and the UE, and between the RAN and the UE, and according to the difference between the situations of the first node corresponding to the specific network element, in the specific implementation of the embodiment of the present application, the manner of transmitting the start time of the period corresponding to the first packet at the UPF may be different.

Specifically, corresponding to the possible situation one in S613, in S616, the UPF sends the first message to the RAN through the GTP-U layer, which may specifically refer to the mode 1 in fig. 11.

Corresponding to the second possible situation in S613, (1) the UPF sends the start time of the period corresponding to the first packet at the UPF to the UE through a protocol layer between the UPF and the UE, where the RAN is required to forward, and the RAN cannot sense the start time of the period corresponding to the first packet at the UPF, and in this embodiment of the present application, the start time may be sent through S616 and S618, which may specifically refer to the mode 3 in fig. 11; or, (2) in S616, the UPF sends the start time of the period corresponding to the first packet at the UPF to the RAN through the GTP-U layer, and in S618, the RAN transmits the start time of the period corresponding to the first packet at the UPF to the UE through the protocol layer between the UE and the RAN, which may specifically refer to mode 2 in fig. 11. It should be appreciated that in (2), the RAN may or may not sense the start time of the period corresponding to the first packet at the UPF, but the RAN does not process the start time of the period corresponding to the first packet at the UPF regardless of whether the RAN senses the start time of the period corresponding to the first packet at the UPF.

Corresponding to the possible case three in S613, the UPF in S616 sends the start time of the corresponding period of the first packet at the UPF to the RAN through the GTP-U layer, which may specifically refer to the mode 1 in fig. 11; the UPF sends the start time of the period corresponding to the first packet at the UPF to the UE through a protocol layer between the UPF and the UE, where the RAN is required to forward the start time, and the RAN cannot sense the start time of the period corresponding to the first packet at the UPF, and in this embodiment of the present application, the start time may be sent through S616 and S618, which may specifically refer to mode 3 in fig. 11.

In a second possible implementation manner, the starting time of the period corresponding to the first packet is the starting time of the period corresponding to the first packet at the RAN/UE.

Corresponding to the possible situation one in S613, the UPF in S616 sends the start time of the corresponding period of the first packet at the RAN to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11.

Corresponding to the second possible situation in S613, (1) the UPF sends, to the UE through a protocol layer between the UPF and the UE, the start time of a period corresponding to the first packet at the UE, where the RAN is required to forward, and the RAN cannot perceive the start time of the period corresponding to the first packet at the UE, and in this embodiment of the present application, the UPF may send the packet through S616 and S618, which may specifically refer to the mode 3 in fig. 11; or, (2) in S616, the UPF sends the start time of the period corresponding to the first packet at the UE to the RAN through the GTP-U layer, and in S618, the RAN transmits the start time of the period corresponding to the first packet at the UE to the UE through the protocol layer between the UE and the RAN, which may specifically refer to mode 2 in fig. 11. It should be understood that, in (2), the RAN may or may not sense the start time of the period corresponding to the first packet at the UE, but no matter whether the RAN senses the start time of the period corresponding to the first packet, the RAN does not process the start time of the period corresponding to the first packet.

Corresponding to the possible case three in S613, the UPF in S616 sends the start time of the period corresponding to the first packet at the RAN to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11; the UPF sends, to the UE through a protocol layer between the UPF and the UE, a start time of a period corresponding to the first packet at the UE, where the RAN is required to forward the start time, and the RAN cannot sense the start time of the period corresponding to the first packet at the UE, and in this embodiment of the present application, the UPF may send the packet through S616 and S618, which may specifically refer to mode 3 in fig. 11. It should be understood that the UPF needs to calculate the starting time of the first message in the RAN/UE corresponding period according to the starting time of the first message in the UPF corresponding period.

Exemplarily, the start time of the period corresponding to the first packet = the start time of the receiving period corresponding to the first packet + the time delay.

It should be understood that when the starting time of the period corresponding to the first message is the starting time of the period corresponding to the first message at the UE, the time delay here is the time delay between the UPF and the UE; when the starting time of the period corresponding to the first message is the starting time of the period corresponding to the first message at the RAN, the time delay here is the time delay between the UPF and the RAN.

It should be noted that, for the second possible implementation, the delay here may be indicated by the SMF to the UPF, or may be preconfigured on the UPF.

S616, the UPF sends the first packet to the RAN, and the time information carried in the first packet specifically refers to the detailed description in S615.

S617, determining a time to forward or process the first packet. S617 is embodied in various implementations, such as S617a and/or S617b below.

It should be understood that corresponding to the possible situation in S613, the RAN performs S617a; when corresponding to the possible case in S613, the UE performs S617b; corresponding to the possible case three in S613, the RAN performs S617a and the UE performs S617b.

S617a, the RAN determines time t3 for forwarding or processing the first packet.

Specifically, the RAN determines time t3 for forwarding or processing the first packet according to the time information encapsulated in the GTP-U packet header, and forwards or processes the first packet at t3 in S618.

(1) Corresponding to S615a, the RAN calculates t3= t2a + k × cycle, where cycle is the message cycle length.

(2) Corresponding to the possible case one in S615b, the RAN calculates the start time + the delay of the corresponding period of the first packet at t3= UPF. The delay here is the delay between the UPF and the RAN. The delay here may be indicated to the RAN by the UPF or SMF, or may be preconfigured on the RAN;

(3) Corresponding to the second possible case in S615b, t3 is the starting time of the corresponding period for the RAN to process the first packet.

S617b, the UE determines a time t4 for forwarding or processing the first packet.

Specifically, the UE receives the time information from the RAN through a protocol layer between the RAN and the UE, or the UE receives the time information from the UPF through a protocol layer between the UE and the UPF, and then the UE determines a time t4 for forwarding or processing the first packet according to the time information, where the time information may specifically be a period number in S615 and a start time of a period corresponding to the first packet.

(1) Corresponding to S615a, the UE calculates t4= t2b + k × cycle, where cycle is a message cycle length.

(2) Corresponding to the first possible case in S615b, the UE calculates the starting time + the delay of the corresponding period of the first packet at t4= UPF. The delay here is the delay between the UPF and the UE. The delay here may be indicated to the UE by the UPF or SMF, or may be preconfigured on the UE;

(3) Corresponding to the second possible situation in S615b, t4 is the starting time of the corresponding period for the UE to process the first packet.

S618, the RAN sends the first packet to the UE at time t3.

For whether the first message in S618 carries the time information of the UE, and whether the RAN senses the time information of the UE, refer to the detailed description in S615.

In the embodiment of the application, under the condition of clock synchronization between the UPF and the RAN/UE, time information, such as the number of a corresponding period of a message or the starting time of the corresponding period of the message, is packaged in the message sent to the RAN/UE through the UPF, and the RAN/UE determines the time for processing/sending the message according to the time information of the message and the reference time corresponding to the first message, so that when different periods and/or a large number of messages reach the UPF, the messages in the same period can be processed/forwarded at the correct time, thereby realizing the deterministic transmission of the messages by node pairs in the 5GS, and avoiding the conflict and packet loss caused by the simultaneous processing of a large number of messages.

Fig. 8 is a schematic interaction diagram of a method 620 of message transmission according to the present application. The method 620 is described in detail with reference to the downlink, where the first node is RAN and the second node is UPF. Further, the first node is a RAN, the second node is a UPF, and the third node is a UE. In the method 620, the information for periodic alignment is sent to the first node or the third node through the second node, and in the method 610, a control plane network element (such as SMF) is required to configure t2 to the RAN or the UE.

The method 620 is mainly described in detail with respect to the first possible case one, the second possible case two, the third possible case three, the fourth possible case four, and the fifth possible case in S503 in the method 500.

S621 is similar to S611 in method 610. S621 is optional, the SMF may optionally determine the cycle length and the arrival time t1 of the packet, and then execute S622 to configure the above information to the UPF; or the SMF may selectively determine the cycle length of the packet, and configure the cycle length to the UPF, where the UPF determines t1 based on its own processing time, for example, taking some arbitrary time on the UPF as t1; or not executing S621, and the UPF uses its own processing cycle as the cycle length of the message, and uses the cycle start time of the UPF as t1.

S622 is similar to S612 in method 610.

S623, the UPF sends, to the RAN/UE, first indication information used for indicating a correspondence between the local time of the UPF and the cycle number of the periodic packet, for example, the indication information may include the cycle number corresponding to the UPF at a certain time (e.g., the first time).

It should be understood that, the UPF determines the first indication information according to the corresponding relationship between the periodic service packet and the local time. Here, the cycle number corresponding to the first time may be a cycle number k corresponding to the first packet, or may be a cycle number corresponding to another packet.

Specifically, S623 has various implementations, and may be, for example, S623a or S623b below.

S623a, the UPF sends the first indication information to the RAN.

It should be understood that the scheme of the embodiment of the present application is not limited to be used between the UE and the RAN or between the UE and the UPF for message transmission.

S623b, the UPF sends the first indication information to the UE.

It should be understood that when the UE is the third node, and the deterministic transmission among the first node, the second node, and the third node is achieved, S623b is executed; when the UE transmits the first packet to the RAN in the existing manner, S623a is performed. The third node here belongs to the 5GS same as the first node and the second node shown in fig. 6 (a).

Corresponding to S623a, the RAN may determine t2a according to the first indication information, or may determine a time for processing or/and forwarding the packet after receiving the time information of the packet subsequently.

Corresponding to S623b, the UE may determine t2b according to the first indication information, or may determine a time for processing or/and forwarding the packet after receiving the time information of the packet subsequently.

It should be noted that the first indication information in S623a and S623b may be sent separately, or may be sent together when the UPF forwards the service packet to the RAN/UE in the subsequent step; the encapsulation method of the indication information may be similar to the encapsulation method of the cycle number in step S615 described below, or may be other methods.

Next, the following explanation is made with respect to the UE/RAN determining t2 from the first indication information:

as an example, the first indication information indicates that the UPF corresponds to a period number 0 at an x ms time, the RAN calculates t2a = x ms + delay, and the UE calculates t2b = x ms + delay.

As an example, the first indication information indicates that the UPF has a corresponding cycle number of 8 at the time of x ms, the ue may calculate t2b = x-8 × cycle + delay in combination with the cycle length of the packet, and the RAN may calculate t2a = x-8 × cycle + delay in combination with the cycle length of the packet. It should be noted that the cycle length cycle of the packet may be indicated by the SMF or the UPF, or may be preconfigured on the RAN/UE.

In the case of S623a, the RAN calculates t2a, which is the time delay between the UPF and the RAN, and in the case of S623b, the UE calculates t2b, which is the time delay between the UPF and the RAN. The delay may be a maximum delay, an average delay, or a fixed delay (for example, a deterministic transmission network is deployed between two nodes, and the delay is fixed), which is not limited in this application. In addition, the delay here may be indicated by the indication information, or may be preconfigured on the RAN/UE.

S624 is similar to S614 in method 610.

S625 is embodied in various implementations, such as S625a or S625b below.

S625a, the UPF calculates the cycle number of the first message, adopts GTP-U to package the first message, and packages the calculated cycle number k in a GTP-U packet header. The specific process is similar to that in S615a, and is not described again.

It should be understood that when the clocks of the first node and the second node are synchronized, the corresponding cycle numbers of the messages in the same cycle on the first node and the second node are consistent. When the clocks of the first node, the second node and the third node are synchronous, the corresponding cycle numbers of the messages in the same cycle on the first node, the second node and the third node are consistent. Therefore, for S623a and S623b, the cycle number carried by the first packet is k.

Due to the difference between the UPF and the RAN, between the UPF and the UE, and between the RAN and the UE, the embodiment of the present application, in a specific implementation, has a difference in the manner of transmitting the cycle number according to the difference in the implementation manner of S623.

Corresponding to S623a, in S626 the UPF sends the cycle number to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11.

When corresponding to S623b, (1) in S626, the UPF sends the cycle number to the RAN through a GTP-U layer, which may specifically refer to mode 1 in fig. 11, and the UPF sends the cycle number to the UE through a protocol layer between the UPF and the UE, where the RAN is required to forward and the RAN cannot sense the cycle number, which may be sent through S626 and S628 in this embodiment of the present application, which may specifically refer to mode 3 in fig. 11; (2) In S616, the UPF sends the cycle number to the RAN through the GTP-U layer, and in S618 the RAN transfers the cycle number to the UE through the protocol layer between the UE and the RAN, which may be specifically referred to as mode 2 in fig. 11, the UPF sends the cycle number to the UE through the protocol layer between the UPF and the UE, where the RAN is required to forward and the RAN cannot sense the cycle number, which may be sent through S626 and S628 in this embodiment of the present application, which may be specifically referred to as mode 3 in fig. 11. It should be understood that, in (2), the RAN can sense the cycle number and determine its own forwarding policy according to the cycle number, which is represented in this embodiment as S627 that the RAN determines, according to the received cycle number, a time t3 for forwarding the first packet.

S625b, packaging the first message by adopting GTP-U, and packaging the initial time of the corresponding period of the first message in a GTP-U packet header. The starting time of the period corresponding to the first packet may be the starting time of the period corresponding to the first packet at the UPF, or the starting time of the period corresponding to the first packet at the RAN/UE.

As a possible case, the starting time of the period corresponding to the first packet here is the starting time of the period corresponding to the first packet at the UPF.

It should be understood that, due to the difference between the protocol layers for transmitting information between the UPF and the RAN, between the UPF and the UE, and between the RAN and the UE, when corresponding to S623a and S623b, respectively, the manner of transmitting the start time of the corresponding period of the first packet at the UPF is different, and the specific situation is similar to that in S615a, only the above "period number" needs to be replaced with the "manner of the start time of the corresponding period of the first packet at the UPF".

In a second possible case, the starting time of the period corresponding to the first packet is the starting time of the period corresponding to the first packet at the RAN/UE.

Corresponding to S623a, in S616, the UPF sends the start time of the corresponding period of the first packet at the RAN to the RAN through the GTP-U layer, which may specifically refer to mode 1 in fig. 11.

Corresponding to S623b, (1) in S626, the UPF sends the start time of the period corresponding to the first packet at the UE to the RAN through the GTP-U layer, which may be specifically shown in fig. 11 as mode 1, the UPF sends the start time of the period corresponding to the first packet at the UE to the UE through the protocol layer between the UPF and the UE, where the RAN is required to forward the packet, and the RAN cannot sense the start time of the period corresponding to the first packet at the UE, which may be sent through S626 and S628 in this embodiment of the present application, which may be specifically shown in fig. 11 as mode 3; (2) In S616, the UPF sends the start time of the period corresponding to the first packet at the UE to the RAN through the GTP-U layer, and in S618, the RAN transmits the start time of the period corresponding to the first packet at the UE to the UE through the protocol layer between the UE and the RAN, which may be specifically referred to as a mode 2 in fig. 11, where the UPF sends the start time of the period corresponding to the first packet at the UE to the UE through the protocol layer between the UPF and the UE, where the RAN needs to forward, and the RAN cannot sense the start time of the period corresponding to the first packet at the UE. It should be understood that, in (2), the RAN may sense the start time of the period corresponding to the first packet at the UE, and determine its own forwarding policy according to the start time of the period corresponding to the first packet at the UE, which is expressed in this embodiment as S627 that the RAN determines, according to the received start time of the period corresponding to the first packet at the UE, the time t3 for forwarding the first packet.

It should be understood that the UPF needs to calculate the starting time of the first message in the corresponding period of the RAN/UE according to the starting time of the corresponding period of the first message in the UPF, for specific implementation, see S615 of the method 610.

S626, the UPF sends the first packet to the RAN, and the time information carried in the first packet specifically refers to the detailed description in S625.

S627, the RAN determines time t3 for forwarding the first packet.

(1) Corresponding to S623a, S625a, the RAN determines t3 from the cycle number. Correspondingly, in S629, the UE determines t4 according to the existing method.

As an example, the RAN has calculated t2a, the RAN calculates t3= t2a + k × cycle, cycle being the cycle length.

As another example, the RAN determines that t3= x + (k-8) × cycle + delay, and cycle is a cycle length, according to the cycle number of 8 corresponding to the UPF indicated by the first indication information in x ms. The delay here is the delay between the UPF and the RAN.

(2) Corresponding to the possible case one in S623a, S625b, the RAN calculates the start time + the delay of the corresponding period of the first packet at t3= UPF. The delay here is the delay between the UPF and the RAN. The delay here may be indicated to the RAN by the UPF or SMF, or may be preconfigured on the RAN.

(3) Corresponding to the possible case two in S623a and S625b, the time information carried in S616 is the start time of the corresponding cycle of the first packet processed by the RAN, and t3 is the start time of the corresponding cycle of the first packet processed by the RAN.

(4) Corresponding to the second possible case of 623b and 625b, the time information carried in S616 is the start time of the corresponding period for the UE to process the first packet. Alternatively, the RAN can be aware of this time information from which the RAN can determine its own forwarding policy, e.g. determine t3. For example, if the RAN starts 4 points according to the period corresponding to the UE processing the first message, t3 must be a time before 4 points. T3 here may also be understood as a time for assisting scheduling, which may be, for example, the time at which the expected message arrives at the RAN at the latest.

S628, the RAN sends the first packet to the UE at time t3.

For whether the first packet carries the time information of the UE in S628 and whether the RAN perceives the time information of the UE, refer to the detailed description in S625.

S629, the UE determines the time t4 for forwarding the first message.

Corresponding to 623b and 625a, the UE determines t4 by combining the first indication information in S623b and the time information of the UE received in S602.

As an example, the UE has calculated t2b, calculating t4= t2b + k × cycle, where cycle is the message cycle length.

As another example, the UE determines that t3= x + (k-8) × cycle + delay, where cycle is a cycle length, according to that the cycle number of the UPF indicated by the first indication information is 8 in x ms. The delay here is the delay between the UPF and the UE.

Corresponding to the first possible case in 623b, 625b, the UE calculates the start time + delay of the corresponding period of the first packet at t4= UPF. The delay here is the delay between the UPF and the UE. The delay here may be indicated to the UE by the UPF or SMF, or may be preconfigured on the UE.

Corresponding to the possible case two in 623b and 625b, the time information carried in S618 is the starting time of the corresponding period for the UE to process the first packet. And the UE calculates the starting time of the corresponding period of t4= UE processing the first message.

In the embodiment of the application, under the condition of clock synchronization between the UPF and the RAN/UE, the UPF sends time information of an UPF side to the RAN/UE before sending a message, for example, a corresponding relation between a cycle number of the message and time, then the time information is packaged in the message sent to the RAN/UE, for example, the number of the corresponding cycle of the message or the initial time of the corresponding cycle of the message, and the RAN/UE determines the time for processing/sending the message according to the time information of the UPF side and the time information packaged in the message, so that when different cycles and/a large number of messages reach the RAN/UE, the messages in the same cycle can be processed/forwarded at correct time, thereby realizing the deterministic transmission of the messages by nodes in 5GS, and avoiding conflict and packet loss caused by simultaneous processing of a large number of messages.

Fig. 9 is a schematic interaction diagram of a method 630 of message transmission according to the present application. The method 630 takes downlink as an example, where the UPF is the second node and the RAN is the first node to implement deterministic transmission between the UPF and the RAN, or the UPF is the second node and the UE is the first node to implement deterministic transmission between the UPF and the UE. In the method 630, the first node sends the second indication information, which is used for aligning the period information between the two nodes, to the second node after the session is created by the control plane or periodically, and the steps of configuring t2 to the first node by the control plane in the method 610 are not required.

The method 630 is mainly described in detail with respect to the method 500, which aligns the periodic relationship between the first node and the second node through step S504.

S631, the SMF determines the cycle length of the message.

S632, the SMF configures a cycle length to the UPF and/or RAN.

S633 has various implementations, and may be, for example, S633a or S633b described below.

S633a, the RAN sends second indication information to the UPF, and the second indication information is used for the UPF to determine the corresponding relation between the period of the message reaching the UPF and the period of the message sent from the RAN; or, in S633b, the UE sends the second information to the UPF, where the second information is used for the UPF to determine a correspondence between a period in which the packet reaches the UPF and a period in which the packet is sent from the UE.

For example, when the SMF creates a session, the RAN/UE receives the session creation/modification request message, and the RAN/UE creates and sends the second indication information to the UPF, or the RAN/UE creates and sends the second indication information to the UPF after a period of time after receiving the session creation/modification request message. Alternatively, the RAN/UE periodically sends the second indication information to the UPF. Alternatively, the RAN/UE may also send the second indication information to the UPF for other reasons, which is not limited in this application.

As an example, taking the step S633a as an example, the RAN sends the second indication information to the UPF, and indicates to the UPF that the cycle start time of the message with the cycle number i on the RAN is cycle _ i. The UPF may determine t1, t1= cycle _ i-cycle × i-delay corresponding to the UPF according to the second indication information, where the cycle is a cycle length, and the delay is as described in S623. Or when the UPF determines the cycle start time of the RAN processing the first packet in S635b, the cycle number of the first packet is k, and the cycle start time of the RAN processing the first packet = cycle _ i + (k-i) cycle.

S634 to S637 are similar to S614 to S617 in the method 610, and are not described herein.

In the embodiment of the present application, under the condition of clock synchronization between the UPF and the RAN/UE, before the UPF sends a packet to the RAN/UE, the RAN/UE sends its own time information to the UPF, for example, a correspondence between a cycle number of the packet and a cycle start time, so that the UPF determines the time information encapsulated in the packet sent to the RAN/UE. After receiving the message, the RAN/UE determines the time for processing/sending the message according to the encapsulated time information in the message, so that when different periods and/or a large number of messages reach the RAN/UE, the messages in the same period can be processed/forwarded at the correct time, the deterministic transmission of the messages by nodes in the 5GS is realized, and meanwhile, the conflict and the packet loss caused by the simultaneous processing of a large number of messages are avoided.

The following describes in detail a method 700 for packet transmission in a scenario where clocks are not synchronized according to the embodiment of the present application with reference to fig. 10.

As shown in fig. 10 (a), when a first node and a second node communicate in 5GS, one or more nodes may also pass between the first node and the second node, where delay 1 to delay 4 in the figure are internal processing delays of each node, and there is a corresponding jitter range, and d1, d2, and d3 in the figure are transmission delays between nodes, and the delay may be a fixed delay or a delay with a jitter range. Because the clocks of the first node and the second node are asynchronous, the first node determines the time for processing the message by detecting the time information of the received message.

The possible case one, the possible case two, and the possible case three in S705 of the method 700 are respectively described in detail with respect to the manner three, the manner four, and the manner five which are possible cases one in S503 of the method 500.

Fig. 10 (b) is a schematic interaction diagram of a method 700 for message transmission according to the present application. Taking the uplink as an example, the first node is a UPF, and the second node is a RAN.

S701, the SMF determines the cycle length of the message, and the maximum Jitter (Jitter) or Jitter range of the transmission delay between the RAN and the UPF.

It should be appreciated that there are many ways that SMF can determine the maximum jitter or jitter range of the transmission delay.

As an example, jitter herein can be understood as the difference between the maximum delay and the minimum delay in message transmission.

As another example, SMF obtains the forwarding delay jitter (delay 1 and/or delay 4 in the figure) of RAN and/or UPF, and obtains the delay jitter on the transmission path from RAN to UPF from the control plane of the transmission network (d 1+ delay 2+ d2+ delay 3+ d3 in the figure), and then adds up the jitter of each segment to obtain the jitter range of the transmission delay between RAN and UPF.

S702, SMF configures the Jitter to UPF of transmission delay through the session creation/modification request, and can select the cycle length of the configuration message.

As a possible case, the frequencies of RAN and UPF are synchronized, and the cycle lengths of the messages corresponding to UPF and RAN are equal in measurement, and the cycle of the message may be configured from the SMF to the UPF, or the cycle of the periodic service message may be detected by the UPF.

In a possible case two, the frequencies of RAN and UPF are not synchronized, and the UPF may detect the period of the periodic traffic message.

S703, the UE periodically forwards the packet to the RAN.

For example, the RAN forwards the message according to the periodic information configured by the control plane.

S704, the RAN periodically forwards the packet to the UPF, where the forwarded packet includes a periodic number.

The RAN calculates the cycle number in a similar manner as S615a in the method 610 described above. Specifically, when the RAN sends the first message to the UPF, the GTP-U packet header includes a cycle number k corresponding to the RAN.

S705, the UPF determines the time for forwarding the message in the period according to the period number.

The UPF receives the message from the RAN and parses the cycle number in the GTP-U header, including several possible scenarios as to how to determine the first time.

One possible scenario is that the maximum Jitter (Jitter) or Jitter range is known and the frequencies of RAN and UPF are synchronized, i.e. the period lengths of RAN and UPF are the same.

As an example, the UPF monitors the arrival time of the header message of each period based on the period number, and detects the minimum value t of the arrival time of the header message _n And adding Jitter as the time for forwarding the message in the period. Specifically, assume that the earliest time among the arrival times of the first packet in the UPF messages with multiple cycle numbers is t _i Then if the UPF detects the arrival time t of the first message in a certain period _m Ratio t _i Smaller, then t _i As t _n The time for forwarding the message in the period is calculated. Or, if a time t is detected _i The current earliest arrival time, the time t of receiving the message when the mth message is received _m <t + (cycle × m), where cycle is the cycle length, then t is said _m If it is the earliest time of arrival of the first message in the currently detected period, t is set _m As t _n The cycle start time is recalculated.

In the second possible scenario, the maximum Jitter (Jitter) or Jitter range is known and the frequencies of RAN and UPF are not synchronized, i.e. the period lengths of RAN and UPF are different.

The method of determining the time to forward the message within the period is approximately the same as the possible case, but since the frequencies of the RAN and the UPF are not synchronized, the period length needs to be determined before the possible case is performed.

With respect to determining the cycle length, specifically, the RAN/UE may accumulate the incremental number of cycles for receiving the packet, and determine relatively accurate cycle information by taking an average value in combination with the local elapsed time.

As an example, t _n The cycle number cycle _ n in the message is received at the moment, and then at t _k The cycle number cycle _ k in the message is received at the moment, and the cycle length is (t) _k -t _n ) And/or (cycle _ k-cycle _ n), without limitation.

And in a possible case three, the maximum Jitter (Jitter) or the Jitter range is unknown, and the RAN/UE detects the latest arrival time of the first message in each period as the time for forwarding the message in the previous period of the period.

As an example, if the time when the header message of the period k arrives at the RAN/UE is t, taking t as the starting time for processing the message of the period k-1; time t of arrival of header message of subsequent period k + n _n <t + cycle x n, then t is _n As the start time of the k + n-1 period, and updates the processing time of the RAN/UE.

S706, the UPF periodically forwards the message at the determined time.

In the embodiment of the present application, in a case that the clock is not synchronized between the UPF and the RAN as a possible case one in S705, the UPF obtains the earliest arrival time of the first message in the period by detecting the messages with the same period-related identifier (for example, the period number), and determines the time for the UPF to process the message in the same period according to the earliest arrival time of the first message in the period and the delay jitter, so that when there are different periods and/or a large number of messages arriving at the UPF, the message in the same period can be processed/forwarded at the correct time, thereby realizing deterministic transmission of the message by the node in 5GS, and avoiding collision and packet loss caused by simultaneous processing of a large number of messages.

In the second possible case in S705, further, in the case that the clocks between the UPF and the RAN are not synchronized and the frequencies are not synchronized, the UPF determines the cycle length of the message by detecting the message with the cycle number that arrives at the UPF, and determines the time for processing the message in the same cycle in combination with the first possible case, thereby achieving the same effect.

For the third possible case in S705, under the condition that the clocks between the UPF and the RAN are not synchronous and the maximum delay or delay jitter is unknown, the UPF obtains the latest arrival time of the first message in the period by detecting the message arriving at the UPF and having the same cycle number, and uses the time as the time for processing the message in the previous period, so that when there are different cycles and/or a large number of messages arriving at the UPF, the message in the same period can be processed/forwarded at the correct time, thereby realizing the deterministic transmission of the message by the node in the 5GS, and avoiding the collision and packet loss caused by processing a large number of messages at the same time.

It should be noted that, in addition to the cycle number and the cycle start time, the time information carried in the packet in the present application may also be the time for receiving/processing the packet by the second node (for example, UPF in the downstream) (the time for processing the packet is determined by the first node at the opposite end according to the time and the transmission delay); alternatively, the time information may be a time when the first node processes/transmits the packet (for example, the second node adds the time when the packet is received/processed to the delay information, and if the delay information is the maximum delay, the time when the packet is received/processed is the latest time when the first node transmits the packet). Specifically, as an example, if the second node is a UPF and the first node is a RAN, the time information in the message may also be a time when the UE sends/processes the message (for example, obtained by adding the time when the UPF receives/processes the message to a time delay between the UE and the UPF), and the RAN determines a time for forwarding the message according to the time, so as to ensure that the message can be sent to the UE before the time specified in the message.

It should be understood that the contents of the two time information listed above are applicable to the scenario of clock synchronization (clock synchronization or clock offset can be obtained).

It should be noted that the time information referred to in this application, for example, the period length, the period number, the period start time, and the like, may be time information corresponding to a service flow, or may be time information in other manners, for example, time information of a device such as an UPF/RAN/UE processing a packet or time information related to scheduling. For example, for the downlink, the UPF may add a corresponding cycle number of the service flow to the message based on the time information of the service flow, and then send the message to the RAN, and then the RAN determines a corresponding scheduling cycle on the RAN according to the time information in the message. This is not limited in this application.

The method for message transmission in the present application is described in detail above with reference to fig. 5 to fig. 10, and an implementation manner of the above method in different scenarios is illustrated below with reference to fig. 11 to fig. 14.

Fig. 11 shows an implementation manner of the message transmission method in the present application in a 5GS scenario.

Mode 1, when the message transmission method is used for communication between the RAN and the UPF, the time information is carried through a GTP-U layer, so that the RAN or the UPF determines the time for processing the message.

Specifically, taking the uplink flow as an example, the time information may include: the RAN sends the cycle number, sending time, and cycle start time of the message, or the UPF processes the message or the cycle number, processing time, cycle start time, and the like of the message reaching the UPF, and the cycle length, and the like. Taking the downstream as an example, the time information may include: the cycle number, the sending time, and the cycle starting time of the UPF sending the message, or the cycle number, the processing time, the cycle starting time, and the cycle length of the RAN processing the message or the message arriving at the RAN.

It should be noted that, regarding the cycle length, the cycle length of the service is described in the present application as an example, and actually, the cycle length may also be a cycle length agreed between nodes, for example, the length of the scheduling cycle may be used as the cycle length here, or may also be another cycle length agreed between nodes, which is not limited in the present application.

In the mode 2, when the method for transmitting the message is used for communication between the UPF and the UE, the time information is transmitted between the UPF and the RAN through a GTP-U layer, and the time information is transmitted between the RAN and the UE through an air interface protocol layer, so that the UPF or the UE can determine the time for processing the message.

Specifically, for example, in the uplink flow, the time information may include: the period number, the sending time, and the period starting time of the UE sending the message, or the period number, the processing time, the period starting time, and the period length of the UPF processing the message or the message arriving at the UPF. Taking downstream as an example, the time information may include: the period number, the sending time, and the period starting time of the UPF sending the message, or the period number, the processing time, the period starting time, and the like of the UE processing the message or the message arriving at the UE, as well as the period length, and the like.

It should be understood that, in the mode 2, the time of the UE is information that is transferred between the UE and the RAN and between the RAN and the UPF, and the RAN may or may not sense the time information of the UE. When the RAN perceives the time information of the UE, the RAN can determine a forwarding strategy according to the time information of the UE, and when the RAN does not perceive the time information of the UE, the RAN can determine the forwarding strategy according to the self condition without considering the time information.

It should be noted that, in the method 2, the transmission path may also be divided into two segments, that is, deterministic transmission is implemented between the UPF and the RAN and between the UE and the RAN by using the scheme of the embodiment of the present application. Specifically, for example, as shown in (a) in fig. 6, between the UPF and the RAN, the UPF is the second node, and the RAN is the first node; between the UE and the RAN, the RAN is the second node, and the UE is the first node. It should be understood that, taking downlink as an example, the RAN needs to sense the time information of the UE sent by the UPF, and the RAN determines its own forwarding policy according to the time information of the UE, and optionally, the RAN may also send new time information obtained after processing the time information of the UE sent by the UPF to the UE.

It should be understood that, in the mode 2, compared to the mode 1, the RAN may transmit, to the UE, information carried by the RAN from the GTP-U protocol layer through the air interface protocol layer between the RAN and the UE, or the RAN may also transmit, to the UPF, information carried by the RAN from the air interface protocol layer through the GTP-U protocol layer.

In the mode 3, when the method for transmitting the message is used for communication between the UE and the UPF, time information is transmitted through a protocol layer between the UE and the UPF, so that the UPF or the UE can determine the time for processing the message.

Specifically, for example, in the uplink flow, the time information may include: the period number, the sending time, and the period starting time of the UE sending the message, or the period number, the processing time, the period starting time, and the like of the UPF processing the message or the message reaching the UPF, and the period length, and the like. Taking downstream as an example, the time information may include: the period number, the sending time, and the period starting time of the UPF sending the message, or the period number, the processing time, the period starting time, and the like of the UE processing the message or the message arriving at the UE, as well as the period length, and the like.

It should be understood that the protocol layer between the UE and the UPF has no relationship with the GTP-U protocol layer and the air interface protocol layer in the mode 1 and the mode 2, and the UPF needs to be forwarded by the RAN when transmitting information with the UE through the protocol layer, but the RAN cannot sense the information in the protocol layer.

It should be noted that, in the embodiment of the present application, a manner of determining the time information of the packet by the 5GS entry is mainly described as a manner of determining based on a time when the network element (e.g., UPF in the case of downstream) of the 5GS entry receives the packet, and may actually be determined according to other manners, which is not limited in the present application.

It should be understood that the above implementations 1, 2, 3 may also be used in combination when communicating between more than two nodes. The method for transmitting the message in the present application is further described by a method 900, taking communication between the UPF and two RANs and two UEs as an example, with reference to fig. 12.

Fig. 12 shows a schematic interaction diagram of a method 900 for determining time information of a message by a UPF when UE1 and UE2 communicate via the UPF.

S901, UE1 adds time information to the message.

The time information here may be the time when the UE1 receives the packet or sends the packet, or may be other types of time information, such as a cycle number, or a time/cycle number when the UE2 receives the packet.

S902, UE1 sends message to UPF, wherein, it transmits through RAN1, inserts time information. For example, UE1 inserts time information in the protocol layer between UE and UPF using method 3 described above.

It should be understood that in S901 and S902, the UE1 is processed in a manner similar to the second node, RAN/UE in the method 700 in the method 500 of the present application.

And S903, after receiving the message, the UPF inserts the time information into a GTP-U layer, and then sends the time information to the RAN2 and the UE2 through S904 and S906 respectively.

It should be understood that the processing manner of the UPF may be similar to that of the second node in the method 500 and the UPF in the method 600 in this application, and specifically, the UPF may determine the time information inserted into the GTP-U layer according to the time information of the message received by the UPF, and may also determine the time information inserted into the GTP-U layer according to the time information in the message (the message in S902) received from the UE 1.

The time information inserted by the UPF at the GTP-U layer may be time information of the RAN2 or time information of the UE2.

As a possible case, the time information inserted by the UPF at the GTP-U layer is time information of the RAN2, and in subsequent S904, with reference to the mode 1 in fig. 11, the RAN2 transmits the time information to the RAN2, and in S905, the RAN2 determines the time for processing the packet according to the time information of the RAN 2. Meanwhile, the UPF inserts the time information of the UE2 in the protocol layer between the UE and the UPF, and forwards the time information to the UE2 through the RAN2 in subsequent S904 and S906, referring to mode 3 in fig. 11.

In a possible case two, the time information inserted by the UPF at the GTP-U layer is the time information of the UE2, and is subsequently delivered to the RAN2 in S904 with reference to the mode 2 in fig. 11. Meanwhile, the UPF inserts the time information of the UE2 in the protocol layer between the UE and the UPF, and forwards the time information to the UE2 through the RAN2 in subsequent S904 and S906, referring to mode 3 in fig. 11. Here, the time information of the UE2 may be time information transmitted by the UE1, or may be time information modified by the UPF.

As an example, it is assumed that UE1 sends the UPF the time when UE1 sends the packet, and the time information of the UPF in the packet sent to UE2 may be the time when UE1 sends the packet, or may also be the cycle number when UE2 sends the packet.

Optionally, the UPF may also determine its message sending time according to time information in a message received from the UE1, and this processing is similar to the UPF in the method 700 and the first node in the method 500 in this application.

As an example, the UPF may determine how much time margin the UPF has to send the message to the UE2 according to the time information in the message received from the UE1 and the time information of the message received by the UPF, and further determine the scheduling and message sending time of the UPF.

S904, the UPF sends the message to the RAN 2.

S904 is specifically implemented as described above in S903.

S905, the RAN2 determines the message processing time based on the time information.

After receiving the message, RAN2 may perform scheduling according to the time information in the GTP-U packet header.

Corresponding to the possible case one in S903, the processing of RAN2 is similar to the first node in method 500 or the RAN in method 610 in this application.

Corresponding to the second possible case in S903, the processing of RAN2 is similar to the processing manner of RAN in the case that RAN is the first node, UPF is the second node, and UE is the third node in the method 620 of the present application.

As an example, the GTP-U packet header indicates the period number of the UE2 sending the packet, and the RAN2 may consider this time information as the latest packet processing time of the UE2, so the RAN2 may determine the policy for the RAN2 to forward the packet according to this information and the current time. Specifically, assuming that the current time is very close to the time when the UE2 sends the packet, the RAN2 needs to forward the packet preferentially.

S906, the RAN2 forwards the packet to the UE2.

As an example, referring to manner 3, UE2 receives the relevant time information through the GTP-U layer between UPF and UE2. After receiving the packet, the UE2 may process the packet based on the first node in the method 500 or the corresponding manner when the UE is the third node in the method 620.

According to the embodiment of the application, on the basis of realizing the deterministic transmission among the nodes, the deterministic transmission from the terminal to the terminal can be further realized.

Next, with reference to fig. 13, an application of the message transmission method in a multi-stream merging synchronous transmission scenario is described.

Fig. 13 shows a scenario of multiflow merging synchronous transmission to which the message transmission method of the present application is applied. As shown in fig. 13, UE1, UE2, and UE3 respectively send a data stream to the UPF through RAN, where the three data streams may belong to a service, and if the messages of the three data streams are combined and transmitted, the Application (APP) may directly process the data stream after receiving the messages, otherwise, the application needs to buffer the data stream received first, and then process the data stream after all the data streams are received. Illustratively, UE1, UE2, and UE3 are devices for audio or video acquisition, and after they have acquired different audio data and different video data of the same service, it needs to transmit data streams belonging to the same service to APP through 5GS, and before APP outputs related service information, it needs to perform synchronization processing on different audio and video, and if the information is synchronized inside 5GS and then sent to APP, the processing efficiency of APP can be improved or the requirement of APP on message synchronization can be met.

As an example, the three UEs use the same time point as the cycle start time, add a cycle number to the data stream, and send the data stream to the UPF, where the UPF may determine, according to the maximum time delay of the three data streams, the latest time of the forwarding/processing times corresponding to the three data streams as the time for synchronization processing. The delay here is the delay of the UE transmission to the UPF. For example, the maximum time delay of the three data streams plus the period start time of the UE side is used as the period start time on the UPF, and the three data streams are merged and transmitted, so that the messages with the same period number in the three data streams are transmitted together in the same period.

According to the embodiment of the application, different data streams belonging to the same service are synchronously processed in the 5GS and then transmitted to the application, so that the step of caching data by the application is omitted, the time delay of application synchronous data is reduced, the processing efficiency of the application is improved, or the requirement of the application on message synchronization is met. The application of the message transmission method of the present application in a deterministic transmission scenario is described below with reference to fig. 14.

Fig. 14 (a) shows a schematic diagram of a deterministic transfer mechanism.

As shown in fig. 14 (a), three switching devices or forwarding devices (switch, SW) SW1, SW2, and SW3 are directly connected (that is, forwarding delay between adjacent devices is a fixed value), and have the same scheduling period, before sending a packet, SW2 sends a synchronization packet to SW1 at the beginning of a certain period, where the synchronization packet is used to synchronize the scheduling periods of SW2 and SW1, after SW1 receives the packet, it determines, according to its internal forwarding capability, a correspondence between the period number of the SW2 scheduling period and the period number of the SW1 scheduling period, for example, the correspondence is that the period number of the scheduling period of SW 1= the period number + m of the scheduling period of SW2, after SW2 sends the packet to SW1, the number n of the scheduling period that sends the packet is added to the packet, after SW1 receives the packet, the packet is sent in the n + m scheduling period of SW1, and the period number n + m is added to the packet. And then all nodes on the forwarding path adopt the same operation to realize deterministic transmission.

It should be understood that the scheduling period is inherent to each device, and is independent of the message or the service to which the message belongs. The cycle number of the scheduling cycle added when the SW2 sends the message to the SW1 is determined according to which scheduling cycle of the SW2 the time for sending the message belongs to, for example, the nth scheduling cycle time of the SW2 is between 3 and zero 10ms and 3 and zero 15ms, and the time for sending the message by the SW2 is 3 and zero 13ms, then the cycle number of the scheduling cycle added when the message is sent by the SW2 is n.

It should be noted that the "synchronization packet" in the present application is unrelated to data or service, and is a packet used for synchronizing or aligning the period or the corresponding relationship of the period number between two nodes.

As shown in (b) in fig. 14, a deterministic transfer mechanism is implemented using 5GS instead of the SW1 node described above.

It should be understood that, according to the above description of the deterministic transmission mechanism in fig. 14 (a), the current cycle number for synchronizing among multiple SWs is the number of the scheduling cycle inherent to the device, and the cycle number for synchronizing in the message transmission method of the present application is the cycle number related to the message. When the message transmission method of the application is applied in a deterministic transmission scenario, the cycle number of the transmission between the SWs may be the number of the scheduling cycle of the device or the cycle number of the message, and the cycle number of the transmission between the UPF and the UE in the 5GS may be the number of the scheduling cycle of the device or the cycle number of the message. When the granularity of the time information transmitted inside the 5GS and the granularity of the time information transmitted outside the 5GS are different, that is, the time information transmitted inside the 5GS and the time information transmitted outside the 5GS use different cycle numbers, the corresponding cycle lengths are different, and the cycle number in the message needs to be modified inside the 5GS to adapt to the deterministic transmission network outside the 5GS.

The following describes how the UPF or the UE modifies the cycle number of the message, taking as an example the case where the cycle number of the scheduling cycle unique to the device is used for the time information transmitted between the SWs, and the cycle number of the message is used between the UPF and the UE.

Example 1, sw2 sends a sync message (the same as the sync message in (a) in fig. 14) to a UPF, and when the UPF sends the sync message to a UE, the UPF sends time information of receiving a message by the UPF or time information of sending a message by the UE in a manner 2 or 3 in fig. 11, and further when the UE receives the sync message, the UE can determine that a cycle number of a scheduling cycle in the current sync message corresponds to the sending time information on the UE, and simultaneously determine a sending cycle of a local egress according to the sending time information, so that the UE can determine a corresponding relationship between the cycle number of the scheduling cycle and the cycle number of the message on the UE, assuming that the corresponding relationship is the cycle number of the message on the UE = cycle number + m of the scheduling cycle. And then when the UPF forwards the message with the scheduling cycle number of n to the UE, the UE determines to send the message with the cycle number of n to the SW3 in the (n + m) th cycle of the scheduling cycle according to the cycle number in the message and the corresponding relation between the cycle number of the scheduling cycle and the cycle number of the message on the UE without modifying the cycle number of the scheduling cycle in the message into the cycle number of the message.

Example 2, sw2 sends a sync message (the sync message in (a) of fig. 14) to the UPF, and the UPF does not forward the sync message to the UE, but when forwarding a data message, determines time information of the UPF according to the time of receiving the message or determines time information of the UE sending the message by means 2 or 3 of fig. 11. The time information here is not necessarily obtained by calculating the UPF directly from the reception time, and may be indirectly determined by combining a periodic correspondence relationship between the UPF and the UE, or the like. And then the UE determines the time information of the message according to the method in the embodiment, and determines the scheduling period corresponding to the time information according to the method of converting the time information of the message into the time information of the scheduling period, thereby realizing that the message is transmitted in the n + m period when the message with the period number of n is received.

It should be noted that the scheme for packet transmission between the first node and the second node in the present application may be applicable to a plurality of communication connection modes. Illustratively, the first node and the second node may be any two network elements of a UPF, a RAN, and a UE, or the first node and the second node may also be two UPFs. Further, in the case that the first node, the second node and the third node communicate, the first node may be a RAN, and the second node and the third node may be one of a UE and a UPF, respectively; or the first node may be a UPF and the second and third nodes may be any two of the UPF, RAN, UE, or the second and third nodes may be two UPFs.

The method provided by the embodiment of the present application is described in detail above with reference to fig. 5 to 14. Hereinafter, the apparatus provided in the embodiment of the present application will be described in detail with reference to fig. 15 to 16.

Fig. 15 is a schematic block diagram of a communication device for message transmission according to an embodiment of the present application. As shown in fig. 15, the communication device 10 may include a transceiver module 11 and a processing module 12.

The transceiver module 11 may be configured to receive information sent by other apparatuses, and may also be configured to send information to other apparatuses. For example, the first time information of receiving the first message or sending the first message. The processing module 12 may be configured to perform content processing of the device, such as determining a first time based on the first time information.

In one possible design, the communication device 10 may correspond to the first node or UPF or RAN/UE in the above-described method embodiment.

In particular, the communication device 10 may correspond to the first node or UPF or RAN/UE in any of the methods 500 to 700 and 900 according to the embodiments of the present application, the communication device 10 may include a module for performing operations performed by the terminal device or UE in the respective methods, and each unit in the communication device 10 is for implementing the operations performed by the first node or UPF or RAN/UE in the respective methods.

Illustratively, when the communication device 10 corresponds to the first node in the method 500, the transceiver module 11 is configured to perform steps S502, S503, and S504.

Illustratively, when the communication device 10 corresponds to the RAN in the method 610, the transceiver module 11 is configured to execute steps S613a, S616, and S618, and the processing module 12 is configured to instruct step S617a.

Illustratively, when the communication device 10 corresponds to the UE in the method 610, the transceiver module 11 is configured to execute steps S613b and S618, and the processing module 12 is configured to instruct step S617b.

Illustratively, when the communication device 10 corresponds to the RAN in the method 620, the transceiver module 11 is configured to execute steps S623a, S626, and S628, and the processing module 12 is configured to instruct step S627.

Illustratively, when the communication device 10 corresponds to the UE in the method 620, the transceiver module 11 is configured to execute steps S623b and S628, and the processing module 12 is configured to instruct step S629.

Illustratively, when the communication device 10 corresponds to the RAN in the method 630, the transceiver module 11 is configured to perform steps S633a, S636, S638, and the processing module 12 is configured to instruct step S637a.

Illustratively, when the communication device 10 corresponds to the UE in the method 630, the transceiver module 11 is configured to perform steps S633b, S638, and the processing module 12 is configured to instruct step S637b.

Illustratively, when the communication device 10 corresponds to the UE in the method 700, the transceiver module 11 is configured to execute steps S702, S704, and S706, and the processing module 12 is configured to instruct step S705.

Illustratively, when the communication device 10 corresponds to the UPF of the method 900, the transceiver module 11 is configured to execute steps S902 and S904, and the processing module 12 is configured to instruct step S903.

Illustratively, when the communication device 10 corresponds to the RAN2 in the method 900, the transceiver module 11 is configured to execute steps S904 and S906, and the processing module 12 is configured to instruct step S905.

Specifically, in a possible embodiment, the transceiver module 11 is configured to receive a first packet from a second node and first time information of the first packet, where the first time information is used to indicate at least one of: a first cycle number corresponding to the first message, a first cycle start time corresponding to the first message, a time for the first node to process the first message, a time for the second node to send the first message, and a time for the third node to send the first message; the transceiver module 11 is further configured to send the first message at a first time according to the first time information.

According to the scheme, the second node sends the time information of the message to the first node, and the first node determines the time for sending or processing the message according to the time information, so that the deterministic transmission of the message by the node in the 5GS can be realized when no deterministic transmission mechanism exists between the first node and the second node or when the jitter of the transmission delay is large and the like. When different periods or a large number of messages reach the first node, the first node can determine the forwarding time of the messages according to the time information, and delay forwarding is carried out on the messages which do not need to be forwarded at present, so that collision and packet loss caused by simultaneous processing of a large number of messages are avoided.

Wherein the first message is received by the first node from the second node over a wireless packet service tunneling protocol user plane, GTP-U.

Optionally, the apparatus further comprises: the first node determines the first time according to the first time information.

Wherein, when the first time information is used to indicate the first cycle number, the processing module 12 is specifically configured to: determining the first time according to the first cycle number, the cycle length and the first starting time; or determining the first time according to the first cycle number, the cycle length, a second start time, and a first time delay, where the first start time is a reference time for calculating a time corresponding to the first packet by the first node, the second start time is a reference time for calculating a time corresponding to the first packet by the second node, and the first time delay is a time delay for transmitting a packet between the first node and the second node.

The processing module 12 is specifically configured to determine the first time according to the first period start time and the first time delay when the first time information is used to indicate the first period start time and the first period start time is the period start time when the second node receives the first packet.

When the first time information is used to indicate the time when the second node sends the first packet, the processing module 12 is specifically configured to: and determining the first time according to the time when the second node sends the first message and the first time delay.

The transceiver module 11 is further configured to receive first indication information from the second node; the processing module 12 is specifically configured to determine the first time according to the first indication information and the first time information, where the first indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, the second time is a cycle start time corresponding to the cycle number on the first node, or the first indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

Wherein, the transceiver module 11 is further configured to: and sending second indication information to the second node, where the first period number or the first period start time corresponds to the first node, the second indication information is used to indicate a correspondence between the period number corresponding to the first node and a second time, the second time is a period start time corresponding to the period number on the first node, or the first period number or the first period start time corresponds to the second node, the second indication information is used to indicate a correspondence between the period number corresponding to the second node and a third time, and the third time is a period start time corresponding to the period number on the second node.

The processing module 12 is specifically configured to determine that the first time is a time obtained by adding a jitter time to an earliest arrival time, where the earliest arrival time is a time at which a packet corresponding to the nth period and a packet in one or more periods before the nth period arrive at the first node, and the jitter time is a jitter time of a transmission delay between the first node and the second node.

The processing module 12 is specifically configured to determine a latest arrival time of the first packet in the (n + 1) th cycle at the first node when the first time information is used to indicate the first cycle number, where n is a positive integer.

The transceiver module 11 is further configured to receive a second packet from a fourth node and second time information of the second packet, where the first packet and the second packet belong to the same service; the processing module 12 is further configured to determine the first time according to the first time information and the second time information; the transceiver module 11 is further configured to send the second packet at the first time.

Wherein, the transceiver module 11 is further configured to: and sending the first message and the first time information to the third node at the first time according to the first time information.

Wherein, the transceiver module 11 is further configured to receive the first delay from the second node; or, the processing module 12 is further configured to obtain the first time delay configured in advance; or, the processing module 12 is further configured to obtain the first time delay through detection; alternatively, the first node obtains the first delay from a control plane network element.

Wherein, the transceiver module 11 is further configured to receive the cycle length from the second node; or, the processing module 12 is further configured to obtain the period length configured in advance; alternatively, the processing module 12 is further configured to obtain the cycle length through detection.

In one possible design, the communication device 10 may correspond to the second node or UPF or RAN/UE in the above-described method embodiment.

In particular, the communication device 10 may correspond to the second node or the UPF or the RAN/UE in any of the methods 500 to 700 and 900 according to the embodiments of the present application, the communication device 10 may include a module for performing operations performed by the radio access network equipment or the base station in the respective methods, and each unit in the communication device 10 is to implement the operations performed by the radio access network equipment or the base station in the respective methods.

Illustratively, when the communication device 10 corresponds to the second node in the method 500, the transceiver module 11 is configured to perform steps S501, S502, and S504.

Illustratively, when the communication device 10 corresponds to the UPF in the method 610, the transceiver module 11 is configured to execute steps S612, S614, and S616, and the processing module 12 is configured to execute step S615a or S615b.

Illustratively, when the communication device 10 corresponds to the UPF of the method 620, the transceiver module 11 is configured to execute steps S622, S623a or S623b, S624, S626, and the processing module 12 is configured to execute step S625a or S625b.

Illustratively, when the communication device 10 corresponds to the UPF of the method 630, the transceiver module 11 is configured to execute steps S632, S634, and S636, and the processing module 12 is configured to execute step S635a or S635b.

Illustratively, when the communication device 10 corresponds to the RAN/UE in the method 700, the transceiver module 11 is configured to perform steps S703 and S704.

Illustratively, when the communication device 10 corresponds to the UE1 in the method 900, the transceiver module 11 is configured to execute step S902, and the processing module 12 is configured to execute step S901.

Illustratively, when the communication device 10 corresponds to the UPF in the method 900, the transceiver module 11 is configured to execute steps S902 and S904, and the processing module 12 is configured to execute step S903.

Illustratively, when the communication device 10 corresponds to the RAN2 in the method 900, the transceiver module 11 is configured to execute steps S904 and S906, and the processing module 12 is configured to execute step S905.

Specifically, in a possible embodiment, the transceiver module 11 is configured to receive a first packet; the transceiver module 11 is further configured to send the first packet and first time information of the first packet to a first node, where the first time information is used to indicate at least one of the following: the first period number corresponding to the first message, the first period starting time corresponding to the first message, the time for the first node to process the first message, the time for the second node to send the first message, and the time for the third node to send the first message, wherein the first time information is used for determining the first time for sending the first message.

According to the scheme, the second node sends the time information of the message to the first node, and determines whether the message is sent or processed according to the time information, so that the deterministic transmission of the message by the node in the 5GS can be realized when no deterministic transmission mechanism exists between the first node and the second node or when the jitter of the transmission delay is large and the like. When different periods or a large number of messages reach the first node, the first node can determine the forwarding time of the messages according to the time information, and delay forwarding is performed on the messages which do not need to be forwarded at present, so that collision and packet loss caused by simultaneous processing of a large number of messages are avoided.

Wherein the first message is sent by the second node to the first node via a wireless packet service tunneling protocol user plane, GTP-U.

Wherein, the transceiver module 11 is further configured to send, to the first node, at least one of: the first start time is a reference time for calculating the time corresponding to the first message by the first node, the second start time is a reference time for calculating the time corresponding to the first message by the second node, and the first delay is a delay for transmitting the message between the first node and the second node.

The transceiver module 11 is further configured to send first indication information to the first node, where the first indication information is used to indicate a correspondence between a cycle number corresponding to the first node and second time, and the second time is a cycle start time corresponding to the cycle number on the first node; or the first indication information is used to indicate a corresponding relationship between a cycle number corresponding to the second node and a third time, where the third time is a cycle start time corresponding to the cycle number on the second node.

The transceiver module 11 is further configured to receive second indication information from the first node; the apparatus further includes a processing module 12, where the processing module 12 is further configured to determine the first time information according to the second indication information, where when the first cycle number corresponds to the first node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the first node and a second time, the second time is a cycle start time corresponding to the cycle number on the first node, or when the first cycle number corresponds to the first cycle start time and the second node, the second indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, and the third time is a cycle start time corresponding to the cycle number on the second node.

Wherein, the method also comprises: the transceiver module 11 is further configured to receive the first time information.

In one possible design, the apparatus 20 may be a first node or UPF or RAM/UE, or may be a chip or a chip system located on the first node or UPF or RAM/UE.

In one possible design, the apparatus 20 may be a second node or UPF or RAN/UE, including various handheld devices, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to a wireless modem, as well as various forms of terminals, mobile stations, terminals, user equipment, soft terminals, etc., and may also be a chip or system-on-chip, etc., located on a terminal device.

The apparatus 20 may include a processor 21 (i.e., an example of a processing module) and a memory 22. The memory 22 is configured to store instructions, and the processor 21 is configured to execute the instructions stored in the memory 22, so as to enable the apparatus 20 to implement the steps performed by the devices in the various possible designs as described above in the corresponding methods in fig. 4 to 12.

Further, the apparatus 20 may further include an input port 23 (i.e., one side of the transceiver module) and an output port 24 (i.e., another side of the transceiver module). Further, the processor 21, memory 22, input port 23 and output port 24 may communicate with each other via internal connection paths, passing control and/or data signals. The memory 22 is used for storing a computer program, and the processor 21 may be used for calling and running the computer program from the memory 22 to control the input port 23 to receive a signal and the output port 24 to send a signal, so as to complete the steps of the method described above for the terminal device, the radio access network device, the UE, or the base station. The memory 22 may be integrated in the processor 21 or may be provided separately from the processor 21.

Alternatively, if the message transmitting device 20 is a communication device, the input port 23 is a receiver and the output port 24 is a transmitter. Wherein the receiver and the transmitter may be the same or different physical entities. When the same physical entity, may be collectively referred to as a transceiver.

Alternatively, if the device 20 is a chip or a circuit, the input port 23 is an input interface, and the output port 24 is an output interface.

As an implementation manner, the functions of the input port 23 and the output port 34 may be realized by a transceiver circuit or a dedicated chip for transceiving. The processor 21 may be considered to be implemented by a dedicated processing chip, processing circuitry, a processor, or a general purpose chip.

As another implementation manner, a device provided by the embodiment of the present application may be implemented by using a general-purpose computer. Program code that implements the functions of the processor 21, the input ports 23 and the output ports 24 is stored in the memory 22, and a general-purpose processor implements the functions of the processor 21, the input ports 23 and the output ports 24 by executing the code in the memory 22.

Each module or unit in the apparatus 20 may be configured to execute each action or processing procedure executed by a device (e.g., a terminal device) performing random access in the foregoing method, and a detailed description thereof is omitted here to avoid redundancy.

For the concepts, explanations, details and other steps related to the technical solutions provided in the embodiments of the present application related to the apparatus 20, please refer to the descriptions of the foregoing methods or other embodiments, which are not repeated herein.

It should be understood that in the embodiments of the present application, the processor may be a Central Processing Unit (CPU), and the processor may also be other general-purpose processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

Embodiments of the present application further provide a computer-readable storage medium, on which computer instructions for implementing the method performed by the second node or the UPF or the RAN/UE in the foregoing method embodiments are stored.

The computer program, when executed by a computer, causes the computer to implement the method of the above method embodiment as performed by the second node or UPF or RAN/UE, for example.

It will also be appreciated that the memory in the embodiments of the subject application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, and not limitation, many forms of RAM are available, such as static random access memory (static RAM, SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous SDRAM (ESDRAM), synchronous Link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

The above-described embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, the above-described embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. The procedures or functions according to the embodiments of the present application are wholly or partially generated when the computer instructions or the computer program are loaded or executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. The semiconductor medium may be a solid state disk.

It should be understood that the term "and/or" herein is merely one type of association relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter associated objects are in an "or" relationship.

It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not imply any order of execution, and the order of execution of the processes should be determined by their functions and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application. It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment. In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a U disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for message transmission, comprising:

the first node receives a first message from a second node and first time information of the first message, wherein the first time information is used for indicating at least one of the following: a first cycle number corresponding to the first message, a first cycle start time corresponding to the first message, a time for the first node to process the first message, a time for the second node to send the first message, and a time for a third node to send the first message;

and the first node sends the first message at the first time according to the first time information.

2. The method of claim 1, wherein the first packet is received by the first node from the second node over a wireless packet service tunneling protocol user plane, GTP-U.

3. The method according to claim 1 or 2, wherein the first node sends the first packet at a first time according to the first time information, and the method comprises:

the first node determines the first time according to the first time information.

4. The method according to claim 3, wherein when the first time information is used to indicate the first cycle number, the first node determines the first time according to the first time information, comprising:

the first node determines the first time according to the first cycle number, the cycle length and the first starting time; alternatively, the first and second electrodes may be,

the first node determines the first time according to the first cycle number, cycle length, second start time, first time delay, wherein,

the first starting time is a reference time for the first node to calculate the time corresponding to the first packet, the second starting time is a reference time for the second node to calculate the time corresponding to the first packet, and the first delay is a delay for transmitting a packet between the first node and the second node.

5. The method according to claim 3, wherein when the first time information is used to indicate the first period start time, the first node determines the first time according to the first time information, comprising:

and when the first period starting time is the period starting time when the second node receives the first message, the first node determines the first time according to the first period starting time and the first time delay.

6. The method of claim 3, wherein when the first time information indicates a time when the second node sends the first packet, the first node determines the first time according to the first time information, and the method comprises:

and the first node determines the first time according to the time when the second node sends the first message and the first time delay.

7. The method according to any of claims 3 to 5, wherein the first node determines the first time from the first time information, comprising:

the first node receives first indication information from the second node;

the first node determines the first time according to the first indication information and the first time information,

wherein the first indication information is used for indicating a corresponding relationship between a cycle number corresponding to the first node and a second time, the second time being a cycle start time corresponding to the cycle number on the first node,

or the first indication information is used to indicate a correspondence between a cycle number corresponding to the second node and a third time, where the third time is a cycle start time corresponding to the cycle number on the second node.

8. The method according to any one of claims 1 to 5, further comprising:

the first node sends second indication information to the second node,

wherein, when the first cycle number or the first cycle start time corresponds to the first node, the second indication information is used to indicate a corresponding relationship between the cycle number corresponding to the first node and a second time, the second time is the cycle start time corresponding to the cycle number on the first node,

or when the first cycle number or the first cycle start time corresponds to the second node, the second indication information is used to indicate a correspondence between the cycle number corresponding to the second node and a third time, where the third time is the cycle start time corresponding to the cycle number on the second node.

9. The method of claim 3, wherein when the first time information is used to indicate the first cycle number, the first node determines the first time according to the first time information, comprising:

the first cycle number is used to indicate that the first packet corresponds to an nth cycle, n is a positive integer, and the first node determines that the first time is a time obtained by adding a jitter time to an earliest arrival time, where the earliest arrival time is an earliest arrival time at the first node among a packet corresponding to the nth cycle and packets in one or more cycles before the nth cycle, and the jitter time is a jitter time of a transmission delay between the first node and the second node.

10. The method according to claim 3, wherein when the first time information is used to indicate the first cycle number, the first node determines the first time according to the first time information, comprising:

the first cycle number is used to indicate that the first packet corresponds to an nth cycle, n is a positive integer, and the first node determines the latest arrival time of the first packet in the (n + 1) th cycle at the first node.

11. The method of claim 1, further comprising:

the first node receives a second message from a fourth node and second time information of the second message, wherein the first message and the second message belong to the same service;

the first node determines the first time according to the first time information and the second time information;

and the first node sends the second message at the first time.

12. The method of claim 1, wherein the first node sending the first packet at a first time according to the first time information comprises:

13. The method according to any one of claims 4 to 6, further comprising:

the first node receiving the first latency from the second node;

or, the first node obtains the first time delay configured in advance;

or, the first node obtains the first time delay through detection.

14. The method of claim 4, further comprising:

the first node receiving the cycle length from the second node;

or, the first node acquires the period length configured in advance;

or, the first node obtains the cycle length through detection.

15. A method for message transmission, comprising:

the second node receives the first message;

the second node sends the first message and first time information of the first message to a first node, wherein the first time information is used for indicating at least one of the following: the first period number corresponding to the first message, the first period starting time corresponding to the first message, the time for the first node to process the first message, the time for the second node to send the first message, and the time for the third node to send the first message, wherein the first time information is used for determining the first time for sending the first message.

16. The method of claim 15, wherein the first packet is sent by the second node to the first node over a wireless packet service tunneling protocol user plane, GTP-U.

17. The method according to claim 15 or 16, further comprising:

the second node sending to the first node at least one of:

a cycle length, a first time delay, a first start time, a second start time,

the first starting time is a reference time for the first node to calculate a time corresponding to the first packet, the second starting time is a reference time for the second node to calculate a time corresponding to the first packet, and the first delay is a delay for transmitting a packet between the first node and the second node.

18. The method according to any one of claims 15 to 17, further comprising:

the second node sends first indication information to the first node,

the first indication information is used for indicating a corresponding relationship between a cycle number corresponding to the first node and second time, where the second time is a cycle start time corresponding to the cycle number on the first node;

19. The method of any one of claims 15 to 17, further comprising:

the second node receives second indication information from the first node;

the second node determines the first time information according to the second indication information,

wherein, when the first period number corresponds to the first period start time and the first node, the second indication information is used to indicate a corresponding relationship between the period number corresponding to the first node and a second time, and the second time is the period start time corresponding to the period number on the first node,

or when the first period number corresponds to the first period start time and the second node corresponds to the second period, the second indication information is used to indicate a correspondence between the period number corresponding to the second node and a third time, where the third time is the period start time corresponding to the period number on the second node.

20. A communications apparatus, comprising:

a processor and a memory;

the memory for storing a computer program;

the processor configured to execute the computer program stored in the memory to cause the communication apparatus to perform the communication method according to any one of claims 1 to 14.

21. A communications apparatus, comprising:

a processor and a memory;

the memory for storing a computer program;

the processor configured to execute the computer program stored in the memory to cause the communication apparatus to perform the communication method according to any one of claims 15 to 19.

22. A computer-readable storage medium having stored therein instructions which, when run on a computer, cause the computer to perform the method of any one of claims 1 to 14 or the method of any one of claims 15 to 19.

23. A chip, comprising:

a memory for storing a computer program;

a processor for reading and executing the computer program stored in the memory, the processor performing the method of any of claims 1 to 14 or performing the method of any of claims 15 to 19 when the computer program is executed.

24. A computer program product, characterized in that it comprises computer program code which, when run on a computer, causes the computer to perform the method of any one of claims 1 to 14 or the method of any one of claims 15 to 19.