Patent Description:
In an existing vehicle-to-everything (Vehicle-to-Everything, V2X) service, when data of the V2X service needs to be forwarded by a base station for locally broadcasting, the data needs to be uploaded to a core network by the base station. After routing, addressing, and forwarding the data, the core network transmits the data to the base station in a downlink manner for broadcasting. Broadcasting of the V2X service is mainly performed within a range near a terminal, that is, performed within coverage of a cell in which the terminal is located or a neighboring cell. It can be learned that, addressing and forwarding of the data of the V2X service by using the core network are unnecessary steps, and addressing and forwarding of the data of the V2X service by using the core network lead to an unnecessary potential latency. This does not meet a low latency requirement of the V2X service.

From <CIT> and <CIT> communication methods involving V2X services are known. In particular, <CIT> teaches a V2X communication system. A vehicle UE i.e. a V-UE may communicate with other V-UEs or with a road side unit RSU. The RSU may be an eNB RSU-E or a stationary UE. The RSU may determine to relay i.e. broadcast the message from the V-UE to other V-UE devices.

Service data transmission methods and a corresponding network device and a corresponding terminal according to the independent claims are provided. Dependent claims provide preferred embodiments, e.g. to reduce a data transmission latency.

According to a first aspect, a service data transmission method for a vehicle-to-everything, V2X, service is provided. The method is performed by a first network device, and the first network device is, for example, a base station. The method includes: obtaining, by the first network device, first configuration information, where the first configuration information includes a first identifier and a first transmission mode corresponding to the first identifier, and the first transmission mode corresponding to the first identifier is a mode in which transmission is performed by using an access network; receiving, by the first network device, first service data and a second identifier that are sent by a terminal; determining, by the first network device based on the first identifier and the second identifier, that a transmission mode of the first service data is the first transmission mode; and transmitting the first service data based on the first transmission mode. The transmitting, by the first network device, the first service data based on the first transmission mode is directly and locally performed without using a core network.

In this example, the first network device may determine, based on the second identifier sent by the terminal and the first configuration information, the transmission mode of the first service data sent by the terminal. If the second identifier matches the first identifier, the transmission mode of the first service data is the mode in which transmission is performed by using the access network. In this case, the first network device may directly transmit the first service data locally without using a core network. Obviously, a redundant step in a data transmission process is removed, thereby shortening a data transmission path, and reducing a data transmission latency.

In a possible design, the obtaining, by the first network device, first configuration information includes: obtaining, by the first network device, preconfigured information, where the preconfigured information includes the first configuration information; or receiving, by the first network device, control signaling sent by a second network device, where the control signaling carries the first configuration information.

For example, the preconfigured information may be preconfigured on the first network device, for example, preconfigured on the first network device by a staff member, and the first network device may directly obtain the preconfigured information locally. If the first configuration information is obtained in this manner, no excessive signaling interaction needs to be performed between the first network device and another network device, so that a transmission resource can be saved. Alternatively, the preconfigured information may be preconfigured in the core network, for example, configured on an MME. The MME may send the preconfigured information to the first network device in advance, and the first network device stores the preconfigured information. In this case, the first network device may also directly obtain the preconfigured information locally. Alternatively, the first configuration information may be preconfigured on the second network device. For example, the first network device sends a request message to the second network device, to request to obtain the first configuration information. After receiving the request message, the second network device may send, to the first network device, the control signaling that carries the first configuration information. In this manner, the first network device may obtain the first configuration information when required, and may not obtain the first configuration information when not required. A storage resource of the first network device may also be saved provided that the first network device can normally obtain the first configuration information.

In a possible design, the first identifier is a data radio bearer identifier between the terminal and the first network device, a flow identifier of a service flow to which the service data belongs, or a specific field in the flow identifier or the data radio bearer identifier; and the second identifier is the data radio bearer identifier between the terminal and the first network device, the flow identifier of the service flow to which the first service data belongs, or the specific field in the flow identifier or the data radio bearer identifier. The first identifier and the second identifier are identifiers of a same type or of different types.

It may be learned that this example provides a plurality of optional first identifiers and second identifiers, and different first identifiers and second identifiers may be selected as required. In addition, the first identifier and the second identifier may have a same type. For example, both the first identifier and the second identifier are the flow identifiers of the service flow to which the service data belongs. Alternatively, the first identifier and the second identifier may have different types. For example, the first identifier is the specific field in the flow identifier of the service flow to which the service data belongs, and the second identifier is the flow identifier of the service flow to which the service data belongs or the bearer identifier. All cases fall within the protection scope of the examples.

In a possible design, the transmitting, by the first network device, the first service data based on the first transmission mode includes: determining, by the first network device, a downlink transmission mode of second service data based on a service type of the first service data, where the second service data is service data obtained by converting the first service data to downlink data when the first service data is transmitted by using the access network, and the downlink transmission mode is a downlink broadcast mode; and transmitting, by the first network device, the second service data based on the determined downlink transmission mode.

The first service data is transmitted in the first transmission mode. In the first transmission mode, the data sent by the terminal first arrives at the first network device, and then is broadcast on a first network device side. In other words, the first transmission mode includes an uplink transmission process and a downlink transmission process. Therefore, the first network device needs to determine the downlink transmission mode. The first service data is service data sent by the terminal to the first network device. To distinguish the uplink transmission process from the downlink transmission process, the service data obtained by converting the first service data to the downlink data when the first service data is transmitted by using the access network is referred to as the service data, in other words, the first network device needs to determine the downlink transmission mode of the second service data.

In this example, the first network device may determine the downlink transmission mode of the second service data based on the type of the first service data. Generally, a type of the service data may determine a transmission range of the service data and the like. In this way, a downlink transmission mode of the service data is determined based on the type of the service data, so that a determining result is relatively accurate.

In a possible design, the first service data further carries quality of service information. In this case, the first network device may further determine, base on the quality of service information and uplink overheads for transmitting the first service data, downlink quality of service information that needs to be satisfied for transmitting the second service data, and select a downlink bearer for the second service data based on the determined downlink quality of service information.

To transmit the second service data, the first network device further needs to determine the downlink bearer. In this example, the first network device may determine, based on the quality of service information carried in the first service data and the uplink overheads for transmitting the first service data, the downlink quality of service information that needs to be satisfied for transmitting the second service data, to select the downlink bearer for the second service data based on the determined downlink quality of service information. The downlink bearer determined in this manner is relatively compliant with an actual requirement of the second service data, and can not only be normally used to transmit the second service data, but also be used to avoid a resource waste.

In a possible design, if the first network device determines that the downlink transmission mode of the second service data is the downlink broadcast mode, the first configuration information further includes a first broadcast indication and a downlink broadcast mode corresponding to the first broadcast indication. In this case, the method further includes: receiving, by the first network device, a second broadcast indication sent by the terminal; and determining, by the first network device, a downlink broadcast mode of the second service data based on the first broadcast indication, the downlink broadcast mode, and the second broadcast indication, where the downlink broadcast mode includes broadcasting in a cell in which the first network device is located, or transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting, or broadcasting in a cell in which the first network device is located and transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting.

This example provides a plurality of downlink broadcast modes. Therefore, the first network device needs to select one from the plurality of downlink broadcast modes to transmit the second service data. The first network device may determine the downlink broadcast mode of the second service data based on the second broadcast indication sent by the terminal and the first configuration information. An appropriate downlink broadcast mode may be selected for the second service data in this manner, so that the second service data can be broadcast in an appropriate range, and better works.

According to a second aspect, a service data transmission method for a vehicle-to-everything, V2X, service is provided. The method is performed by a terminal. The method includes: sending, by the terminal, first service data and a second identifier to a first network device, where the second identifier is used by the first network device to determine a transmission mode of the first service data; and receiving, by the terminal, second service data transmitted by the first network device in a first transmission mode, where the first transmission mode is determined based on the second identifier and is a mode in which transmission is performed by using an access network, and the second service data is service data obtained by converting the first service data to downlink data when the first service data is transmitted by using the access network. The receiving, by the terminal, second service data transmitted by the first network device in a first transmission mode is directly and locally performed without using a core network.

In this example, the terminal sends not only the first service data to the first network device, but also the second identifier to the first network device. As can be learned from the description of the first aspect, the first network device may determine, based on the second identifier sent by the terminal and the first configuration information, the transmission mode of the first service data sent by the terminal. If the second identifier matches the first identifier, the transmission mode of the first service data is the mode in which transmission is performed by using the access network, and the first network device may directly transmit the first service data locally without using a core network. Obviously, a redundant step in a data transmission process is removed, thereby shortening a data transmission path, and reducing a data transmission latency.

In a possible design, the second identifier is a data radio bearer identifier between the terminal and the first network device, a flow identifier of a service flow to which the first service data belongs, or a specific field in the flow identifier or the data radio bearer identifier.

In a possible design, the method further includes: sending, by the terminal, a second broadcast indication to the first network device, where the second broadcast indication is used by the first network device to determine a downlink broadcast mode of the second service data, where the downlink broadcast mode includes broadcasting in a cell in which the first network device is located, or transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting, or broadcasting in a cell in which the first network device is located and transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting.

This example provides a plurality of downlink broadcast modes. Therefore, the first network device needs to select one from the plurality of downlink broadcast modes to transmit the second service data. The first network device may determine the downlink broadcast mode of the second service data based on the second broadcast indication sent by the terminal and the first configuration information. Therefore, the terminal may send the second broadcast indication to the first network device. An appropriate downlink broadcast mode may be selected for the second service data in this manner, so that the second service data can be broadcast in an appropriate range, and better works.

According to a third aspect, a network device is provided. The network device has functions for implementing the network device in the foregoing method design. These functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or the software includes one or more units corresponding to the functions.

The network device includes a processing unit and a receiving unit. The processing unit and the receiving unit may perform corresponding functions in the method provided in any one of the first aspect or the possible designs of the first aspect.

According to a fourth aspect, a terminal is provided. The terminal has functions for implementing the terminal in the foregoing method design. These functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or the software includes one or more units corresponding to the functions.

The terminal includes a sending unit and a receiving unit. The sending unit and the receiving unit may perform corresponding functions in the method provided in any one of the second aspect or the possible designs of the second aspect.

To make objectives, technical solutions, and advantages of examples clearer, the examples are described below in detail with reference to accompanying drawings.

A technology described in this specification may be applied to various communications systems, such as a long term evolution (Long Term Evolution, LTE) system, a fifth-generation mobile communications system (<NUM>), and another such communications system.

In the following, some terms of the examples are described, to help a person skilled in the art have a better understanding.

To better understand the technical solutions provided in the examples, the technical background of the examples is first described below.

LTE is a mainstream wireless communications technology at present. The D2D technology is used as an important feature and has been standardized, and supports direct communication between terminals. Considering that some communication scenarios of a V2X service (for example, V2V/V2I) also belong to terminal direct communication, data of the V2X service may be transmitted by using the D2D technology. Referring to <FIG>, a base station, a vehicle <NUM>, and a vehicle <NUM> are included. The vehicle <NUM> and the vehicle <NUM> may directly communicate in a direct connection manner. However, sometimes, due to blocking of a building (for example, a crossroad) or a requirement that a vehicle needs to transmit a message farther, another communication mode needs to be used. For example, relaying by the base station, the vehicle may transmit the data of the V2X service to the base station, and then the base station transmits the data of the V2X service to another vehicle, to implement Internet of Vehicles communication. An interface used by the vehicle to communicate with a surrounding terminal in a direct connection manner may be a PC5 interface, and an interface between the vehicle and the base station may be a Uu interface.

However, in an existing V2X service, when data of the V2X service needs to be forwarded by the base station for locally broadcasting, the data of the V2X service needs to be uploaded to a core network by the base station. After routing, addressing, and forwarding the data of the V2X service, the core network transmits the data of the V2X service to the base station in a downlink manner for broadcasting. <FIG> includes a base station, an MME, a vehicle <NUM>, a vehicle <NUM>, and a vehicle <NUM>. For example, if the vehicle <NUM> generates data of a V2X service that needs to be locally broadcast, the vehicle <NUM> sends the data to the base station, and the base station forwards the data of the V2X service to the MME in a core network. The MME routes, addresses, and forwards the data of the V2X service, and then sends the data of the V2X service to the base station, and the base station broadcasts the data of the V2X service.

Broadcasting of the V2X service is mainly performed within a range near the terminal, that is, performed within coverage of a cell in which the terminal is located or a neighboring cell. It can be learned that, addressing and forwarding of the V2X data by using the core network are unnecessary steps. In addition, addressing and forwarding of the data of the V2X service by using the core network bring an unnecessary potential latency. This does not meet a low latency requirement of the V2X service.

In view of this, an example provides a new service data transmission method. In this example, a first network device may determine, based on a second identifier sent by a terminal and first configuration information, a transmission mode of first service data sent by the terminal. If the second identifier matches a first identifier, the transmission mode of the first service data is a mode in which transmission is performed by using an access network. In this case, the first network device may directly transmit the first service data locally without using a core network. Obviously, a redundant step in a data transmission process is removed, thereby shortening a data transmission path, and reducing a data transmission latency.

Before the technical solution provided in the examples is described, application scenarios of the examples are first described.

<FIG> is a schematic diagram of an application scenario according to an example. <FIG> includes a terminal <NUM>, a terminal <NUM>, a terminal <NUM>, and a base station. For example, if the terminal <NUM> generates service data that needs to be locally broadcast, the terminal <NUM> sends the service data to the base station, and the base station may directly broadcast the service data without using a core network. <FIG> is a schematic diagram of another application scenario according to an example. <FIG> includes a terminal <NUM>, a terminal <NUM>, a terminal <NUM>, a base station <NUM>, and a base station <NUM>. The base station <NUM> and the base station <NUM> are neighboring base stations, the terminal <NUM> is a terminal covered by the base station <NUM>, and the terminal <NUM> and the terminal <NUM> are terminals covered by the base station <NUM>. For example, if the terminal <NUM> generates service data that needs to be locally broadcast, the terminal <NUM> sends the service data to the base station <NUM>, the base station <NUM> then sends the service data to the base station <NUM>, and the base station <NUM> may broadcast the service data without using a core network. In addition to the base station <NUM>, the base station <NUM> may also perform broadcasting. In <FIG>, an example in which broadcasting is performed by only the base station <NUM> is used.

An example in which all the terminals in <FIG> are vehicles is used.

A technical solution provided in an example is described below with reference to the accompanying drawings.

An example provides a service data transmission method. The method may be performed by a first network device, and the first network device is, for example, a base station. In the following description process, an example in which the method is applied to the application scenario shown in <FIG> or the application scenario shown in <FIG> is used. <FIG> is a flowchart of the method. The first network device obtains first configuration information.

In this example, the first configuration information includes a first identifier and a first transmission mode corresponding to the first identifier, in other words, it may be considered that the first configuration information includes a correspondence between the first identifier and the first transmission mode. The first transmission mode is an end-to-end transmission mode, and is specifically a mode in which transmission is performed by using an access network. The mode in which transmission is performed by using the access network means that service data sent by a terminal is directly forwarded on a base station side without using a core network. For example, the base station may broadcast the service data by using a Uu interface, or forward the service data to a neighboring base station by using an X2 interface.

The first network device may obtain the first configuration information in different manners.

In an example, the first network device may obtain preconfigured information, and the preconfigured information includes the first configuration information.

For example, the preconfigured information may be preconfigured on the first network device, for example, preconfigured on the first network device by a staff member, and the first network device may directly obtain the preconfigured information locally when implementing S51. Alternatively, the preconfigured information may be preconfigured in the core network, for example, configured on an MME. The MME may send the preconfigured information to the first network device in advance, and the first network device stores the preconfigured information. In this case, when implementing S51, the first network device may also directly obtain the preconfigured information locally.

In another example, the first network device receives control signaling sent by a second network device, and the control signaling carries the first configuration information. The second network device is a device in the core network, for example, the MME.

In this case, the first configuration information may be preconfigured on the second network device. When implementing S51, the first network device may send a request message to the second network device, to request to obtain the first configuration information. After receiving the request message, the second network device may send the control signaling that carries the first configuration information to the first network device.

Certainly, the foregoing several manners are merely examples. This example does not limit a manner in which the first network device obtains the first configuration information.

In this example, the first identifier may be a bearer identifier of an uplink bearer between the terminal and the access network. For example, if the first network device is a base station, the first identifier may be a data radio bearer (Data Radio Bearer, DRB) identifier, where the DRB is a bearer between the terminal and an air interface of the base station, and is used to carry user plane data. Alternatively, the first identifier may be a specific field in the data radio bearer identifier, a flow identifier of a service flow to which the service data belongs, a specific field in the flow identifier, or a temporarily defined identifier. This is not limited in this example.

The first identifier may include an identifier corresponding to a non-IP service of V2X, for example, include a bearer identifier of an uplink bearer between the terminal and the core network when the non-IP service of V2X is processed, or include a flow identifier of a service flow to which service data of the non-IP service of V2X belongs. Broadcasting of a V2X service is mainly performed in a range near the terminal, that is, performed within coverage of a cell in which the terminal is located or a neighboring cell, and the non-IP service of V2X does not require addressing. Therefore, addressing and forwarding of the non-IP service data of V2X by using the core network are unnecessary steps. Therefore, in this example, the mode in which transmission is performed by using the access network without using the core network may be set for the non-IP service of V2X, thereby reducing the redundant steps and reducing a latency.

The terminal sends service data and a second identifier to the first network device, and the first network device receives the service data and the second identifier that are sent by the terminal. For example, the service data is referred to as first service data.

For example, the second identifier may be added to the first service data and sent together with the first service data, or the second identifier and the first service data may be sent as two independent parts. In addition, if the second identifier and the first service data are used as two independent parts, the terminal may send the first service data and the second identifier together, or may first send the first service data and then send the second identifier, or may first send the second identifier and then send the first service data. This is not limited in this example.

In this example, the second identifier may be the bearer identifier of the uplink bearer between the terminal and the access network, for example, the DRB identifier, or the second identifier may be a specific field in the bearer identifier, for example, the specific field in the DRB identifier, or the second identifier may be the flow identifier of the service flow to which the first service data belongs, the specific field in the flow identifier, or the temporarily defined identifier. This is not limited in this example.

The first identifier and the second identifier may be identifiers of a same type. For example, both the first identifier and the second identifier are bearer identifiers, or both the first identifier and the second identifier are flow identifiers. Alternatively, the first identifier and the second identifier may be identifiers of different types. For example, the first identifier is the bearer identifier, and the second identifier is the flow identifier, or the first identifier is the bearer identifier, and the second identifier is the specific field in the bearer identifier.

The first network device determines, based on the first identifier and the second identifier, that a transmission mode of the first service data is the first transmission mode. It may be understood that the first network device determines the transmission mode of the first service data based on the second identifier and the first configuration information.

After receiving the second identifier, the first network device matches the second identifier with the first identifier. If the second identifier successfully matches the first identifier, the first network device may consider the first service data as service data of the non-IP service of V2X, and determine the transmission mode of the first service data to be the first transmission mode. However, if the second identifier fails to match the first identifier, the first service data may not be the service data of the non-IP service of V2X. For such first service data, the first network device may transmit the first service data according to a specification in the prior art, for example, transmit the first service data by using the mode in which transmission is performed by using the core network. To be specific, the service data sent by the terminal is forwarded by the base station and the core network, and then transmitted to a peer terminal by the base station. Alternatively, the first network device may still transmit the first service data based on the first transmission mode. This is specifically set by a system or specified in a protocol.

If the first identifier and the second identifier are identifiers of a same type, and if the first identifier is the same as the second identifier, the first network device determines that the first identifier successfully matches the second identifier; otherwise, the first network device determines that the first identifier fails to match the second identifier.

If the first identifier and the second identifier are identifiers of different types, a correspondence exists between the first identifier and the second identifier. For example, the first network device may store the correspondence between the first identifier and the second identifier in advance. In this case, if the first network device determines that a correspondence exists between the received second identifier and any first identifier in the first configuration information, the first network device determines that the first identifier successfully matches the second identifier; and if the first network device determines that no correspondence exists between the received second identifier and any first identifier in the first configuration information, the first network device determines that the first identifier fails to match the second identifier. The correspondence between the first identifier and the second identifier may also be included, for example, in the preconfigured information, or the second network device may send the first configuration information and the correspondence between the first identifier and the second identifier to the first network device by using the control signaling, or the first network device may obtain the correspondence between the first identifier and the second identifier in another manner. This is not limited in this example. The first network device transmits the first service data based on the determined first transmission mode, and the terminal receives the first service data transmitted by the first network device in the first transmission mode. To be specific, if the first identifier successfully matches the second identifier, the first network device transmits the first service data based on the first transmission mode.

The first service data is transmitted in the first transmission mode. In the first transmission mode, data sent by the terminal first arrives at the base station, and then is broadcast on the base station side. That is, the first transmission mode includes an uplink transmission process and a downlink transmission process, and the uplink transmission process is actually completed in S52. Therefore, in this case, the downlink transmission process remains to be completed.

Although both the uplink transmission process and the downlink transmission process are included in the first transmission mode, the first transmission mode may also include different downlink transmission modes. Therefore, the first network device needs to determine a downlink transmission mode of the first service data. The first service data is the service data sent by the terminal to the first network device. To distinguish the uplink transmission process from the downlink transmission process, service data obtained by converting the first service data to downlink data when the first service data is transmitted by using the access network is referred to as second service data, in other words, the first network device needs to determine the downlink transmission mode of the second service data. It should be understood that the first service data and the second service data are same data, and different names are given to distinguish the uplink transmission process from the downlink transmission process.

In this example, the first network device may determine the downlink transmission mode of the second service data based on a type of the first service data. As described above, the first service data may be broadcast service data of the non-IP service of V2X. Therefore, the type of the first service data may be a "broadcast type", and the first network device may determine a downlink transmission mode corresponding to the service data of the "broadcast type". For example, the first network device determines that the downlink transmission mode corresponding to the service data of the "broadcast type" is the downlink broadcast mode, that is, determines that the downlink transmission mode of the first service data is the downlink broadcast mode.

As described above, the technical solution provided in this example may be applied to the application scenario shown in <FIG> or the application scenario shown in <FIG>. That is, this example provides a plurality of downlink broadcast modes, and the first network device needs to select one from the plurality of downlink broadcast modes to transmit the second service data. The plurality of downlink broadcast modes include, but are not limited to, broadcasting in a cell in which the base station is located, or transmitting the second service data to a cell in which a neighboring base station is located for broadcasting, or broadcasting in a cell in which the base station is located and transmitting the second service data to a cell in which a neighboring base station is located for broadcasting. The mode of broadcasting in the cell in which the base station is located may be applied to the application scenario shown in <FIG>, and the mode of transmitting the second service data to the cell in which the neighboring base station is located for broadcasting, or broadcasting in the cell in which the base station is located and transmitting the second service data to the cell in which the neighboring base station is located for broadcasting may be applied to the application scenario shown in <FIG>. For the first network device, the plurality of downlink broadcast modes include broadcasting in a cell in which the first network device is located, or transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting, or broadcasting in a cell in which the first network device is located and transmitting the second service data to a cell in which a neighboring first network device is located for broadcasting.

In an example, the first network device may determine the downlink broadcast mode of the second service data based on a second broadcast indication, a first broadcast indication, and a downlink broadcast mode. It may be understood as that the first network device may determine the downlink broadcast mode of the second service data based on the second broadcast indication and a correspondence between a broadcast indication and a broadcast mode.

Specifically, the first configuration information may further include the first broadcast indication and a downlink broadcast mode corresponding to the first broadcast indication, that is, include a correspondence between the first broadcast indication and the downlink broadcast mode. In S52 in this example, in addition to sending the first service data and the second identifier to the first network device, the terminal may further send the second broadcast indication to the first network device, and the first network device receives the second broadcast indication. For example, the second broadcast indication may be added to the first service data and sent with the first service data together, or the second broadcast indication and the first service data may be sent as two independent parts. In addition, if the second broadcast indication and the first service data are used as two independent parts, the terminal may send the first service data and the second broadcast indication together, or may first send the first service data and then send the second broadcast indication, or may first send the second broadcast indication and then send the first service data. This is not limited in this example.

In this case, the first network device may match the first broadcast indication with the second broadcast indication, and if the second broadcast indication successfully matches any first broadcast indication included in the first configuration information, the first network device determines that a downlink broadcast mode corresponding to the successfully matched first broadcast indication in the first configuration information is the downlink broadcast mode of the second service data. If the second broadcast indication fails to match all first broadcast indications included in the first configuration information, the first network device may select any downlink broadcast mode for the second service data, or the first network device may use another transmission mode to transmit the second service data. This is not limited in this example.

The first broadcast indication is, for example, a temporarily specified identifier, and the second broadcast indication is also, for example, a temporarily specified identifier. In addition, the first broadcast indication and the second broadcast indication may be set in a same manner or different manners. If the first broadcast indication and the second broadcast indication are set in the same manner, that is, if the first broadcast indication is the same as the second broadcast indication, the first network device determines that the first broadcast indication successfully matches the second broadcast indication; otherwise, the first network device determines that the first broadcast indication fails to match the second broadcast indication. If the first broadcast indication and the second broadcast indication are set in different manners, a correspondence may exist between the first broadcast indication and the second broadcast indication. In this case, if a correspondence exists between the second broadcast indication and any first broadcast indication included in the first configuration information, the first network device determines that the second broadcast indication successfully matches the first broadcast indication in the first configuration information; and if no correspondence exists between the second broadcast indication and any first broadcast indication included in the first configuration information, the first network device determines that the second broadcast indication fails to match the first broadcast indication.

Furthermore, in addition to determining the downlink transmission mode of the second service data, the first network device may further determine a downlink bearer of the second service data. In an example, the first network device may determine the downlink bearer of the second service data based on quality of service (Quality of Service, QoS) information sent by the terminal and uplink overheads for transmitting the first service data.

Specifically, in S52 in this example, in addition to sending the first service data and the second identifier to the first network device, the terminal may further send the QoS information to the first network device, and the first network device receives the QoS information. For example, the QoS information may be added to the first service data and sent together with the first service data, or the QoS information and the first service data may be sent as two independent parts. In addition, if the QoS information and the first service data are used as two independent parts, the terminal may send the first service data and the QoS information together, or may first send the first service data and then send the QoS information, or may first send the QoS information and then send the first service data. This is not limited in this example. The first network device may learn the uplink overheads for transmitting the first service data. Therefore, the first network device may correspondingly deduce, based on the received QoS information and the uplink overheads for transmitting the first service data, downlink QoS information that needs to be satisfied for transmitting the second service data. For example, the first network device may deduce, based on the received QoS information and the uplink overheads for transmitting the first service data, a latency that needs to be satisfied by the downlink bearer for transmitting the second service data. Alternatively, for example, if the first network device determines, based on the received QoS information, an uplink packet loss rate for transmitting the first service data, a packet loss rate that the downlink bearer for transmitting the second service data needs to satisfy may be deduced based on the uplink packet loss rate and the uplink overheads for transmitting the first service data. Certainly, the foregoing is only an example. A manner in which the first network device determines the downlink QoS information is not limited in this example. After determining the downlink QoS information, the first network device may select the downlink bearer for the second service data based on the downlink QoS information, and determine the downlink bearer for transmitting the second service data.

Subsequently, the first network device transmits the second service data, based on the determined downlink transmission mode, that is, the selected downlink broadcast mode, by using the selected downlink bearer. To be specific, the terminal receives the first service data transmitted by the first network device in the first transmission mode. Actually, the terminal receives the second service data transmitted by the first network device in the first transmission mode.

According to the technical solution provided in this example, the first service data is directly transmitted in a loopback manner by using the base station without using the core network, and the redundant step in the data transmission process is removed, thereby shortening the data transmission path and reducing the data transmission latency.

Devices provided in the examples are described below with reference to the accompanying drawings.

Referring to <FIG>, an example provides a network device. The network device includes a receiver <NUM> and a processor <NUM>.

The processor <NUM> may include a central processing unit (central processor unit, CPU) or an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), one or more integrated circuits configured to control program execution, a hardware circuit developed by using a field programmable gate array (Field Programmable Gate Array, FPGA), or a baseband chip.

The receiver <NUM> is, for example, an antenna or a communications interface, and is configured to communicate with an external device.

In a possible implementation, the network device may further include a memory <NUM>, which is shown in <FIG> together with the receiver <NUM> and the processor <NUM>. The memory <NUM> is not a mandatory component, and therefore is drawn in a form of a dashed-line box in <FIG>, to be distinguished from the mandatory components. There may be one or more memories <NUM>. The memory <NUM> may include a read-only memory (Read Only Memory, ROM), a random access memory (Random Access Memory, RAM), a magnetic disk memory, or the like. The memory <NUM> may be configured to store program code required by the processor <NUM> for executing a task, and may be further configured to store data.

The receiver <NUM> and the memory <NUM> may be connected to the processor <NUM> by using a system bus, or may be each connected to the processor <NUM> by using a dedicated connection cable (this is used as an example in <FIG>).

The receiver <NUM> is configured to receive first service data and a second identifier that are sent by a terminal. The processor <NUM> is configured to: obtain first configuration information, where the first configuration information includes a first identifier and a first transmission mode corresponding to the first identifier, and the first transmission mode corresponding to the first identifier is a mode in which transmission is performed by using an access network; determine a transmission mode of the first service data based on the first identifier, the second identifier, and the first transmission mode; and transmit the first service data based on the determined transmission mode.

Specifically, the receiver <NUM> may be configured to perform S52 in the example shown in <FIG>, and if the first network device in S51 in the example shown in <FIG> receives the control signaling sent by the MME, the receiver <NUM> is also configured to perform S51, and/or support another process of the technologies described in this specification. The processor <NUM> may be configured to perform S51, S53, and S54 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. All related content of the steps in the foregoing method example may be cited in functional descriptions of corresponding functional modules, and details are not described herein again.

The network device may be the first network device in the example shown in <FIG>.

Referring to <FIG>, an example provides a terminal. The terminal includes a receiver <NUM> and a transmitter <NUM>.

The transmitter <NUM> is, for example, an antenna or a communications interface, and is configured to communicate with the external device.

In a possible implementation, the terminal may further include a processor <NUM>, which is shown in <FIG> together with the receiver <NUM> and the transmitter <NUM>. The processor <NUM> is not a mandatory component, and therefore is drawn in a form of a dashed box in <FIG>, to be distinguished from the mandatory components. The processor <NUM> may include a CPU or an ASIC, one or more integrated circuits configured to control program execution, a hardware circuit developed by using an FPGA, or a baseband chip.

In a possible implementation, the terminal may further include a memory <NUM>, which is shown in <FIG> together with the receiver <NUM> and the transmitter <NUM>. The memory <NUM> is not a mandatory component, and therefore is drawn in a form of a dashed-line box in <FIG>, to be distinguished from the mandatory components. There may be one or more memories <NUM>. The memory <NUM> may include a ROM, a RAM, a magnetic disk memory, and the like. The memory <NUM> may be configured to store program code required by the processor <NUM> for executing a task, and may be further configured to store data.

The receiver <NUM>, the transmitter <NUM>, and the memory <NUM> may be connected to the processor <NUM> by using a system bus, or may be each connected to the processor <NUM> by using a dedicated connection cable (this is used as an example in <FIG>).

The transmitter <NUM> is configured to send first service data and a second identifier to a first network device, where the second identifier is used by the first network device to determine a transmission mode of the first service data. The receiver <NUM> is configured to receive second service data transmitted by the first network device in a first transmission mode. The first transmission mode is determined based on the second identifier and is a mode in which transmission is performed by using an access network, and the second service data is service data obtained by converting the first service data to downlink data when the first service data is transmitted by using the access network. For how the first network device determines the transmission mode of the first service data, refer to the related description in the example shown in <FIG>.

Specifically, the transmitter <NUM> may be configured to perform S52 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. The receiver <NUM> may be configured to perform S54 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. All related content of the steps in the foregoing method example may be cited in functional descriptions of corresponding functional modules, and details are not described herein again.

The terminal may be the terminal in the example shown in <FIG>.

In addition, the network device provided in the example shown in <FIG> may alternatively be implemented in another form. For example, the network device includes a receiving unit and a processing unit that are connected to each other. The receiving unit may be configured to perform S52 in the example shown in <FIG>, and if the first network device in S51 in the example shown in <FIG> receives the control signaling sent by the MME, the receiving unit is also configured to perform S51, and/or support another process of the technologies described in this specification. The processing unit may be configured to perform S51, S53, and S54 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. All related content of the steps in the foregoing method example may be cited in functional descriptions of corresponding functional modules, and details are not described herein again.

In addition, the terminal provided in the example shown in <FIG> may alternatively be implemented in another form. For example, the terminal includes a sending unit and a receiving unit. The sending unit may be configured to perform S52 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. The receiving unit may be configured to perform S54 in the example shown in <FIG>, and/or support another process of the technologies described in this specification. All related content of the steps in the foregoing method example may be cited in functional descriptions of corresponding functional modules, and details are not described herein again.

Because the network device and the terminal provided in this example may be configured to perform the service data transmission method, for technical effects that can be achieved by the network device and the terminal, refer to the foregoing method example, and details are not described herein again.

The examples are described with reference to the flowcharts and/or block diagrams of the method, the device (system), and the computer program product according to the examples. It should be understood that computer program instructions may be used to implement each process and/or each block in the flowcharts and/or the block diagrams and a combination of a process and/or a block in the flowcharts and/or the block diagrams. These computer program instructions may be provided for a general-purpose computer, a special-purpose computer, an embedded processor, or a processor of any other programmable data processing device to generate a machine, so that the instructions executed by a computer or a processor of any other programmable data processing device generate an apparatus for implementing a specific function in one or more processes in the flowcharts and/or in one or more blocks in the block diagrams.

All or some of the foregoing examples may be implemented by using software, hardware, firmware, or any combination thereof. When software is used to implement the examples, the examples may be implemented completely or partially in a form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the procedure or functions according to the examples are all or partially generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or another programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or may be transmitted from a computer-readable storage medium to another readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another web site, computer, server, or data center in a wired (for example, a coaxial cable, an optical fiber, or a digital subscriber line (DSL)) or wireless (for example, infrared, radio, and microwave, or the like) manner. The computer-readable storage medium may be any usable medium accessible by a computer, or a data storage device, such as a server or a data center, integrating one or more usable media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, or a magnetic tape), an optical medium (for example, a DVD), a semiconductor medium (for example, a solid-state drive (Solid State Disk, SSD)), or the like.

Claim 1:
A service data transmission method for a vehicle-to-everything, V2X, service, comprising:
obtaining (S51), by a first network device, first configuration information, wherein the first configuration information comprises a first identifier and a first transmission mode corresponding to the first identifier, and the first transmission mode corresponding to the first identifier is a mode in which transmission is performed by using an access network;
receiving, by the first network device, first service data and a second identifier that are sent by a terminal;
determining (S53), by the first network device based on the first identifier and the second identifier, that a transmission mode of the first service data is the first transmission mode; and
transmitting (S54), by the first network device, the first service data based on the first transmission mode; wherein
the transmitting (S54), by the first network device, the first service data based on the first transmission mode is directly and locally performed without using a core network.