CN117750424A

CN117750424A - Communication method, communication device and communication system

Info

Publication number: CN117750424A
Application number: CN202211116854.7A
Authority: CN
Inventors: 王丹; 周汉; 魏鑫鹏; 李汉成
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-09-14
Filing date: 2022-09-14
Publication date: 2024-03-22
Also published as: WO2024055692A1

Abstract

The application discloses a communication method, a communication device and a communication system, which relate to the field of communication and are used for saving transmission resources. The communication method comprises the following steps: receiving a first set of protocol data units, PDUs, of a first service used at the terminal device and a second set of PDUs of a second service used at the terminal device, wherein the first set of PDUs and the second set of PDUs are mapped to different quality of service, qoS, flows; transmitting a first PDU set to an access network element; if the transmission of the first PDU set fails, determining whether to send the second PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set.

Description

Communication method, communication device and communication system

Technical Field

The present disclosure relates to the field of communications, and in particular, to a communication method, a communication device, and a communication system.

Background

In the fifth generation (5th generation,5G) communication system, in order to guarantee the end-to-end service quality of a service, a concept of a quality of service (quality of service, qoS) flow (flow) is proposed. Traffic data flows are carried and differentiated management is achieved in protocol data unit (protocol data unit, PDU) sessions by quality of service (quality of service, qoS) flows, each QoS flow being uniquely identifiable by a QoS flow identity (QoS flow identifier, QFI).

There is sometimes a dependency between the PDU sets (sets) mapped to different QoS flows. Illustratively, traffic flows of one extended quality (XR) traffic may be mapped into different QoS flows, intra-coded picture (I) frames and forward predictive-coded picture (P) frames of a video stream are mapped to different QoS flows, respectively, or base and enhancement layers of a video stream are mapped to different QoS flows, respectively, and so on, there still exists a dependency relationship between PDU sets mapped to different QoS flows. For example, assuming that all I frames are mapped into QoS flow 1 and all P frames are mapped into QoS flow 2, the P frames in QoS flow 2 need to be decoded depending on the I frames belonging to the same group of pictures (group of pictures) in QoS flow 1 or the previous P frames belonging to the same GoP in QoS flow 2, once the dependent I frames or P frames fail to be transmitted, the dependent P frames cannot be decoded due to lack of reference frames even if they are transmitted successfully, and thus transmission of these P frames wastes transmission resources.

Disclosure of Invention

The embodiment of the application provides a communication method, a communication device and a communication system, which are used for saving transmission resources.

In order to achieve the above purpose, the embodiments of the present application adopt the following technical solutions:

In a first aspect, a communication method is provided, including: the user plane function network element receives a first protocol data unit PDU set of a first service used at the terminal device and a second PDU set of a second service used at the terminal device, wherein the first PDU set and the second PDU set are mapped to different quality of service QoS flows; the user plane function network element sends a first PDU set to the access network element; if the transmission of the first PDU set fails, the user plane function network element determines whether to send the second PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set.

According to the communication method provided by the embodiment of the application, when the user plane function network element determines that the first PDU set transmitted from the access network element to the terminal equipment fails to be transmitted, whether the second PDU set is transmitted to the access network element is determined according to the dependency relationship between the second PDU set and the first PDU set, so that the problem that the second PDU set is transmitted under any condition but cannot be analyzed correctly is avoided, transmission resources are wasted, and therefore the transmission resources can be saved.

In one possible implementation manner, the determining, by the user plane function network element, whether to send the second PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set includes: and the user plane function network element re-transmits the first PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set, and determines whether to transmit the second PDU set to the access network element.

On the premise that the user plane function network element determines to send the first PDU set to the access network element again, whether to send the second PDU set to the access network element is determined, otherwise, because the second PDU set depends on the first PDU set, even if the user plane function network element sends the second PDU set, the second PDU set cannot be resolved correctly by the terminal device, and transmission resources are wasted.

In one possible implementation, determining whether to send the second set of PDUs to the access network element includes: the user plane function network element obtains air interface congestion information of the access network element; the user plane function network element determines whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element and/or according to the attribute information of the second PDU set.

The user plane function network element determines whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element, so as to preferentially ensure the normal communication of the network. The user plane functional network element determines whether to send the second PDU set to the access network element according to the attribute information of the second PDU set, because the second PDU set may be determined to be an important PDU set according to the attribute information of the second PDU set sometimes, so as to send the second PDU set to the access network element, so as to ensure transmission of the important PDU set. For example, if the second PDU set is a P frame with a forward sequence, the user plane function network element still sends the second PDU set to the access network element even if the air interface of the access network element is congested.

In a possible implementation manner, the user plane function network element obtains air interface congestion information of the access network element, including: the user plane function network element receives air interface congestion information from the access network element or the session management function network element, or the user plane function network element obtains the air interface congestion information through QoS monitoring, for example, the transmission delay becomes larger to indicate that the air interface is congested.

In a possible implementation manner, the determining, by the user plane function network element, whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element and/or according to the attribute information of the second PDU set includes: if the air interface congestion information indicates that the air interface of the access network element is not congested, the user plane function network element sends a second PDU set to the access network element; or if the air interface congestion information indicates that the air interface of the access network element is congested, the user plane functional network element sends the second PDU set to the access network element according to the attribute information of the second PDU set, for example, if the air interface of the access network element is congested, but the second PDU set is a P frame with a front time sequence, the user plane functional network element still sends the second PDU set to the access network element so as to ensure the transmission of the important PDU set.

In one possible implementation, resending the first set of PDUs to the access network element comprises: and if the transmission time point of the next period is not reached, delaying to the transmission time point of the next period to resend the first PDU set to the access network element.

For the requirements of periodic resource allocation or discontinuous reception (connected mode discontinuous reception, CDRX) of the connection state of the terminal device, the access network element expects that the received data is periodic, so if the transmission time point of the next period is not reached, the user plane function network element delays to the transmission time point of the next period to transmit the second PDU set to the access network element.

In one possible implementation, sending the second set of PDUs to the access network element includes: and if the transmission time point of the next period is not reached, delaying the transmission time point of the next period to transmit the second PDU set to the access network element.

For the requirements of periodic resource allocation or CDRX of terminal equipment, the access network element expects the received data to be periodic, so if the sending time point of the next period is not reached, the user plane function network element delays to the sending time point of the next period to send the second PDU set to the access network element.

In one possible embodiment, the method further comprises: if the user plane functional network element determines not to send the second PDU set to the access network element, the user plane functional network element sends dormancy indication information to the access network element, wherein the dormancy indication information is used for indicating that the second PDU set is not sent to the terminal equipment at N periodic sending time points in the future, and N is the number of the second PDU sets cached in a period of time.

This embodiment allows the terminal device to sleep during this period of time without having to receive downstream data to reduce power consumption.

In one possible implementation, the first PDU set is mapped to a first QoS flow, and the data packet carrying the first PDU set includes an identifier of the first QoS flow and an identifier of the first PDU set; the method further comprises the steps of: the user plane function network element receives a failure indication message from the access network element, wherein the failure indication message comprises an identifier of a first QoS flow and an identifier of a first PDU set, the failure indication message is used for indicating that the transmission of the first PDU set fails, and the received identifier of the first QoS flow and the received identifier of the first PDU set are used for indicating the user plane function network element to determine a second PDU set according to the first PDU set.

The embodiment enables the access network element to notify the user plane function network element of the transmission failure of the first PDU set, and further enables the user plane function network element to determine the second PDU set according to the first PDU set.

In one possible implementation manner, the data packet carrying the first PDU set includes an identifier of the first PDU set and an association identifier of the first PDU set, which corresponds to the second PDU set together; the method further comprises the steps of: the user plane function network element receives a failure indication message from the access network element, wherein the failure indication message comprises an association identifier and an identifier of a first PDU set, the failure indication message is used for indicating that the transmission of the first PDU set fails, and the received association identifier and the received identifier of the first PDU set are used for indicating the user plane function network element to determine a second PDU set according to the first PDU set.

In one possible implementation, the first set of PDUs are I frames in the video stream and the second set of PDUs are P frames that are co-group with the I frames; or the first PDU set is the P frame with the front time sequence in the video stream, and the second PDU set is the P frame with the rear time sequence which is the same as the P frame with the front time sequence; or the first PDU set is a base layer in the video stream, and the second PDU set is an enhancement layer in the video stream; alternatively, the first set of PDUs is one of video (corresponding to video traffic), audio (corresponding to audio traffic), or haptic (corresponding to perceptual traffic) that serves the same user, and the second set of PDUs is the remaining at least one of video, audio, haptic.

In a video stream of a service stream, if the transmission of an I frame fails, a P frame dependent on the I frame cannot be resolved even if the transmission is successful, and transmission resources can be saved without transmitting the P frame. For another example, in a video stream of a service stream, if the base layer fails to transmit, the enhancement layer depending on the base layer cannot be resolved even if the transmission is successful, and transmission resources can be saved without transmitting the enhancement layer. For another example, the plurality of terminals respectively receive the video, the audio and the touch sense, if the video transmission fails, the user cannot obtain the complete experience even though the audio and the touch sense of the video are output depending on the output, and transmission resources can be saved without transmitting the audio and the touch sense; or, any one of the video, the audio and the touch is not transmitted successfully, the user cannot obtain the complete experience, and transmission resources can be saved by not transmitting the other two data.

In a second aspect, a communication method is provided, including: the access network element receives a first protocol data unit PDU set of a first service used at the terminal device and a second PDU set of a second service used at the terminal device from the user plane function network element, wherein the first PDU set and the second PDU set are mapped to different quality of service QoS flows; the access network element sends a first PDU set to the terminal equipment; if the transmission of the first PDU set fails, the access network element determines whether to send the second PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set.

According to the communication method provided by the embodiment of the application, when the access network element determines that the transmission of the first PDU set transmitted to the terminal equipment fails, whether the second PDU set is transmitted to the terminal equipment is determined according to the dependency relationship between the second PDU set and the first PDU set, so that the situation that the second PDU set is transmitted under any condition and cannot be analyzed correctly is avoided, transmission resources are wasted, and therefore the transmission resources can be saved.

In one possible implementation manner, the determining, by the access network element, whether to send the second PDU set to the terminal device according to the dependency relationship between the second PDU set and the first PDU set includes: the access network element re-transmits the first PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set, and determines whether to transmit the second PDU set to the terminal equipment.

On the premise that the access network element determines to send the first PDU set to the terminal equipment again, whether to send the second PDU set to the terminal equipment is determined, otherwise, because the second PDU set depends on the first PDU set, even if the access network element sends the second PDU set, the second PDU set cannot be resolved correctly by the terminal equipment, and transmission resources are wasted.

In one possible implementation, determining whether to send the second set of PDUs to the terminal device includes: the access network element determines whether to send the second PDU set to the terminal device according to the air interface congestion information and/or according to the attribute information of the second PDU set.

The access network element determines whether to send the second PDU set to the terminal device according to the air interface congestion information of the access network element, so as to ensure the normal communication of the network preferentially. The access network element determines whether to send the second PDU set to the terminal device according to the attribute information of the second PDU set, because it may be determined that the second PDU set is an important PDU set according to the attribute information of the second PDU set, so as to send the second PDU set to the terminal device, so as to ensure transmission of the important PDU set. For example, if the second PDU set is a P frame with a forward sequence, the access network element still sends the second PDU set to the terminal device even if the air interface of the access network element is congested.

In one possible implementation, the first PDU set is mapped to a first QoS flow, the second PDU set is mapped to a second QoS flow, the data packet carrying the first PDU set includes first PDU set dependency information, the first PDU set dependency information includes an identifier of the first QoS flow and an identifier of the first PDU set, the data packet carrying the second PDU set includes second PDU set dependency information, and the second PDU set dependency information includes an identifier of the first QoS flow, an identifier of the second QoS flow, an identifier of the first PDU set, and an identifier of the second PDU set; the first PDU set dependency information and the second PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set. This embodiment provides a way to indicate that the second set of PDUs is dependent on the first set of PDUs.

In a possible implementation manner, the data packet carrying the first PDU set includes third PDU set dependency information, and the third PDU set dependency information includes an association identifier and an identifier of the first PDU set; the data packet carrying the second PDU set comprises fourth PDU set dependent information, and the fourth PDU set dependent information comprises an association identifier, an identifier of the first PDU set and an identifier of the second PDU set; the third and fourth PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set. This embodiment provides another way of indicating that the second set of PDUs is dependent on the first set of PDUs.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising: the access network element receives the first QoS flow dependence information and the second QoS flow dependence information from the session management function network element, or the data packet bearing the first PDU set comprises the first QoS flow dependence information, and the data packet bearing the second PDU set comprises the second QoS flow dependence information; the first QoS flow dependency information includes an identifier of the first QoS flow, first dependency indication information, and second QoS flow dependency information, where the first dependency indication information is used to indicate that a PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that a PDU set mapped to the second QoS flow is dependent on other PDU sets, and the first QoS flow dependency information and the second QoS flow dependency information are used to indicate that the second QoS flow is dependent on the first QoS flow. Indicating that the second QoS flow is dependent on the first QoS flow.

In one possible implementation, the first QoS flow dependency information further includes an identification of the second QoS flow. Indicating that the second QoS flow is dependent on the first QoS flow.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising: the access network element receives third QoS flow dependence information and fourth QoS flow dependence information from the session management function network element, or the data packet bearing the first PDU set comprises the third QoS flow dependence information, and the data packet bearing the second PDU set comprises the fourth QoS flow dependence information; the third QoS flow dependency information includes an identifier of the first QoS flow, an association identifier, and first dependency indication information, the fourth QoS flow dependency information includes an identifier of the second QoS flow, an association identifier, and second dependency indication information, where the first dependency indication information is used to indicate that the PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that the PDU set mapped to the second QoS flow is dependent on other PDU sets, and the third QoS flow dependency information and the fourth QoS flow dependency information are used to indicate that the second QoS flow depends on the first QoS flow. Indicating that the second QoS flow is dependent on the first QoS flow.

In a possible implementation manner, the group identifier is included in the data packet carrying the first PDU set and the data packet carrying the second PDU set, or the identifier of the first PDU set is further included in the data packet carrying the second PDU set, so as to indicate that the second PDU set depends on the first PDU set. The second set of PDUs is further determined to be dependent on the first set of PDUs in combination with the second QoS flow being dependent on the first QoS flow as described above.

In a possible implementation, the data packet carrying the first PDU set further includes an identification of the second PDU set. Indicating that the second set of PDUs is dependent on the first set of PDUs.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising: the access network element receives configuration information of a first QoS flow, wherein the configuration information of the first QoS flow comprises sharing indication information and QoS parameters, and the sharing indication information is used for indicating the first QoS flow and the second QoS flow to share the QoS parameters.

The sharing indication information indicates that all QoS flows of the traffic flow share a certain QoS parameter. For example, assuming that I, P frames belonging to one video stream are mapped to a first QoS stream and a second QoS stream, respectively, the two QoS streams can be indicated to commonly use 10M of bandwidth by sharing indication information, and if the two QoS streams are indicated to have 10M of bandwidth without sharing indication information, the video stream occupies 20M of bandwidth in total, which is likely to cause congestion of transmission resources.

In a possible implementation manner, the sharing indication information is an association identifier or an identifier of the second QoS flow; wherein the association identifies QoS flows for associating all shared QoS parameters. The form of the sharing indication information is not limited in the present application.

In a third aspect, a communication method is provided, including: the user plane function network element receives a first protocol data unit PDU set of a first service used at the terminal device and a second PDU set of a second service used at the terminal device, wherein the first PDU set and the second PDU set are mapped to different quality of service QoS flows; the user plane function network element sends a first PDU set to the access network element; the access network element sends a first PDU set to the terminal equipment; if the transmission of the first PDU set fails, the user plane function network element determines whether to send the second PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set.

In a possible implementation manner, the user plane function network element obtains air interface congestion information of the access network element, including: the user plane function network element receives the air interface congestion information from the access network element or the session management function network element, or the user plane function network element obtains the air interface congestion information through QoS monitoring.

In a possible implementation manner, the determining, by the user plane function network element, whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element and/or according to the attribute information of the second PDU set includes: if the air interface congestion information indicates that the air interface of the access network element is not congested, the user plane function network element sends a second PDU set to the access network element; or if the air interface congestion information indicates that the air interface of the access network element is congested, the user plane function network element sends the second PDU set to the access network element according to the attribute information of the second PDU set.

In one possible implementation, the first set of PDUs are I frames in the video stream and the second set of PDUs are P frames that are co-group with the I frames; or the first PDU set is the P frame with the front time sequence in the video stream, and the second PDU set is the P frame with the rear time sequence which is the same as the P frame with the front time sequence; or the first PDU set is a base layer in the video stream, and the second PDU set is an enhancement layer in the video stream; alternatively, the first set of PDUs is one of video, audio, or haptic serving the same user and the second set of PDUs is the remaining at least one of video, audio, haptic.

In a fourth aspect, a communication method is provided, including: the user plane function network element sends a first protocol data unit PDU set of a first service used at the terminal equipment and a second PDU set of a second service used at the terminal equipment to the access network element, wherein the first PDU set and the second PDU set are mapped to different QoS flows; the access network element sends a first PDU set to the terminal equipment; if the transmission of the first PDU set fails, the access network element determines whether to send the second PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set.

In one possible implementation, the first PDU set is mapped to a first QoS flow, the second PDU set is mapped to a second QoS flow, the data packet carrying the first PDU set includes first PDU set dependency information, the first PDU set dependency information includes an identifier of the first QoS flow and an identifier of the first PDU set, the data packet carrying the second PDU set includes second PDU set dependency information, and the second PDU set dependency information includes an identifier of the first QoS flow, an identifier of the second QoS flow, an identifier of the first PDU set, and an identifier of the second PDU set; the first PDU set dependency information and the second PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set.

In a possible implementation manner, the data packet carrying the first PDU set includes third PDU set dependency information, and the third PDU set dependency information includes an association identifier and an identifier of the first PDU set; the data packet carrying the second PDU set comprises fourth PDU set dependent information, and the fourth PDU set dependent information comprises an association identifier, an identifier of the first PDU set and an identifier of the second PDU set; the third and fourth PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising: the access network element receives the first QoS flow dependence information and the second QoS flow dependence information from the session management function network element, or the data packet bearing the first PDU set comprises the first QoS flow dependence information, and the data packet bearing the second PDU set comprises the second QoS flow dependence information; the first QoS flow dependency information includes an identifier of the first QoS flow, first dependency indication information, and second QoS flow dependency information, where the first dependency indication information is used to indicate that a PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that a PDU set mapped to the second QoS flow is dependent on other PDU sets, and the first QoS flow dependency information and the second QoS flow dependency information are used to indicate that the second QoS flow is dependent on the first QoS flow.

In one possible implementation, the first QoS flow dependency information further includes an identification of the second QoS flow.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising: the access network element receives third QoS flow dependence information and fourth QoS flow dependence information from the session management function network element, or the data packet bearing the first PDU set comprises the third QoS flow dependence information, and the data packet bearing the second PDU set comprises the fourth QoS flow dependence information; the third QoS flow dependency information includes an identifier of the first QoS flow, an association identifier, and first dependency indication information, the fourth QoS flow dependency information includes an identifier of the second QoS flow, an association identifier, and second dependency indication information, where the first dependency indication information is used to indicate that the PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that the PDU set mapped to the second QoS flow is dependent on other PDU sets, and the third QoS flow dependency information and the fourth QoS flow dependency information are used to indicate that the second QoS flow depends on the first QoS flow.

In a possible implementation manner, the group identifier is included in the data packet carrying the first PDU set and the data packet carrying the second PDU set, or the identifier of the first PDU set is further included in the data packet carrying the second PDU set, so as to indicate that the second PDU set depends on the first PDU set.

In a possible implementation, the data packet carrying the first PDU set further includes an identification of the second PDU set.

In a possible implementation manner, the sharing indication information is an association identifier or an identifier of the second QoS flow; wherein the association identifies QoS flows for associating all shared QoS parameters.

In a fifth aspect, there is provided a communications device comprising a processor and a memory in which instructions are stored which, when executed by the processor, perform a method as described in any of the first to fourth aspects and any implementation thereof.

In a sixth aspect, there is provided a communication system comprising a communication device as described in the fifth aspect.

In a seventh aspect, there is provided a computer readable storage medium comprising instructions which, when run on a communication device, cause the communication device to perform the method of any of the first to fourth aspects and any implementation thereof.

In an eighth aspect, there is provided a computer program product comprising instructions which, when run on a communication device as described above, cause the communication device to perform the method of the first aspect and any of its embodiments.

In a ninth aspect, a chip system is provided, the chip system comprising a processor for supporting a communication device to implement the functions referred to in the first to fourth aspects above. In one possible design, the device may further include interface circuitry that may be used to receive signals from other devices (e.g., memory) or to send signals to other devices (e.g., communication interfaces). The system-on-chip may include a chip, and may also include other discrete devices.

The technical effects of the third to ninth aspects are referred to the technical effects of the first to second aspects and any embodiments thereof and are not repeated here.

Drawings

Fig. 1 is a schematic architecture diagram of a communication system according to an embodiment of the present application;

fig. 2 is a schematic diagram of a QoS flow provided in an embodiment of the present application;

fig. 3 is a flow chart of a first communication method according to an embodiment of the present application;

fig. 4 is a flow chart of a second communication method according to an embodiment of the present application;

fig. 5 is a flow chart of a third communication method according to an embodiment of the present application;

fig. 6 is a flow chart of a fourth communication method according to an embodiment of the present application;

fig. 7 is a flow chart of a fifth communication method according to an embodiment of the present application;

fig. 8 is a flow chart of a sixth communication method according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a chip system according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The network architecture and the service scenario described in the embodiments of the present application are for more clearly describing the technical solution of the embodiments of the present application, and do not constitute a limitation on the technical solution provided in the embodiments of the present application, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of the new service scenario, the technical solution provided in the embodiments of the present application is also applicable to similar technical problems.

In the embodiments of the present application, "/" indicates that the symbol is "or" in relation to the symbol.

The embodiment of the application can be applied to a time division duplex (time division duplexing, TDD) scene, a frequency division duplex (frequency division duplexing, FDD) scene and is not limited.

The embodiments of the present application are described by referring to the scenario of a 5G network in a wireless communication network, and it should be noted that, the schemes in the embodiments of the present application may also be applied to other wireless communication networks, and the corresponding names may also be replaced by names of corresponding functions in other wireless communication networks.

Fig. 1 provides a communication system architecture comprising: terminal equipment 101, radio access network (R) AN element 102, user plane function (user plane function, UPF) element 103, data Network (DN) 104, access and mobility management function (access and mobility management function, AMF) element 105, session management function (session management function, SMF) element 106, policy control element (policy control function, PCF) element 107, unified data management element (unified data management, UDM) element 108, application function (application function, AF) element 109, authentication server function (authentication server function, AUSF) element 110, and network slice selection function (network slice selection function, NSSF) element 111.

It should be noted that the interface names between the network elements in fig. 1 are only an example, and the interface names may be other names in the specific implementation, and are not limited. For example, the interface between the terminal device 101 and the AMF network element 105 may be an N1 interface, the interface between the RAN network element 102 and the AMF network element 105 may be an N2 interface, the interface between the RAN network element 102 and the UPF network element 103 may be an N3 interface, the interface between the UPF network element 103 and the SMF network element 106 may be an N4 interface, the interface between the PCF network element 107 and the AF network element 109 may be an N5 interface, the interface between the UPF network element 103 and the DN 104 may be an N6 interface, the interface between the SMF network element 106 and the PCF network element 107 may be an N7 interface, the interface between the AMF network element 105 and the UDM network element 108 may be an N8 interface, the interface between the UPF network element 103 and the UPF network element 103 may be an N9 interface, the interface between the SMF network element 106 and the UDM network element 108 may be an N10 interface, the interface between the AMF network element 105 and the AF network element 109 may be an N11 interface, the interface between the aum network element 107 and the udf network element 107 may be an N25 and the AMF network element 110 may be an N13 interface between the AMF network element 105 and the AMF network element 110 may be an N13 interface between the asf network element 110 and the asf network element 110.

Terminal device 101 may include various handheld devices, vehicle mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem with wireless communication capabilities; and may also include a subscriber unit (subscriber unit), a cellular phone (cell phone), a smart phone (smart phone), a wireless data card, a personal digital assistant (personal digital assistant, PDA) computer, a tablet computer, a wireless modem (modem), a hand-held device (handheld), a laptop computer (laptop), a cordless phone (cord) or a wireless local loop (wireless local loop, WLL) station, a machine type communication (machine type communication, MTC) terminal, a User Equipment (UE), a Mobile Station (MS), a terminal device (terminal device), a relay user equipment, or the like. Wherein the relay user equipment may be a 5G home gateway (residential gateway, RG). For convenience of description, the above-mentioned devices may be collectively referred to as terminal devices.

RAN network element 102 provides devices for wireless access to terminal device 101 including, but not limited to, a gndeb, a wireless fidelity (wireless fidelity, wi-Fi) access point, a worldwide interoperability for microwave access (world interoperability for microwave access, wiMAX) base station, and the like. The RAN network element may be a RAN network element, which is a RAN network element accessing the 5G core network, may be an NR gNodeB, or may be an evolved universal terrestrial radio access (evolved universal terrestrial radio access, E-UTRA) network element in LTE.

The UPF network element 103 is mainly responsible for handling user messages, such as forwarding, charging, etc. The UPF network element may be a unicast UPF network element, a multicast UPF network element, or a multicast broadcast user plane function (MB-UPF) network element. The unicast UPF network element and the multicast UPF network element may be the same UPF network element. The unicast UPF network element is functionally identical to the multicast UPF network element, except that the unicast UPF network element transmits a unicast data stream of the current terminal device (the UPF network element may also transmit a multicast data stream, such as a multicast data stream of a multicast service of another terminal device), and the multicast UPF network element transmits a multicast data stream of the current terminal device (the UPF network element may also transmit a unicast data stream). Both unicast UPF network elements and multicast UPF network elements send data flows in the form of tunnels to the RAN network elements. The MB-UPF network element is a UPF network element dedicated to transmitting multicast data streams, i.e. to transmit multicast data streams, and to transmit multicast data streams in multicast form to the RAN network element.

DN 104 refers to a network providing a data transmission service for a user, such as an IP Multimedia Service (IMS), the Internet (Internet), etc. Terminal device 101 accesses the application server (application server, AS) in DN 104 by establishing a protocol data unit (protocol data unit, PDU) session between the terminal device, RAN network element 102, UPF network element 103, and DN 104.

The AMF network element 105 is mainly responsible for mobility management in mobile networks, such as user location update, user registration network, user handover, etc. The AMF network element 105 may be a multicast access and mobility management function (multicast access and mobility management function, M-AMF) network element. The M-AMF network element is an AMF network element dedicated to managing multicast contexts, in which temporary mobile group identities (temporary mobile group identity, TMGI) of multicast traffic are stored, as well as a first internet protocol (internet protocol, IP) multicast address and a generic tunnel endpoint identity (common tunnel endpoint identifier, C-TEID) of the corresponding MB-UPF network element.

The SMF network element 106 is mainly responsible for session management in the mobile network, such as session establishment, modification, release. For example, specific functions include: the user is assigned an IP address, a UPF providing a message forwarding function is selected, etc. The SMF network element 106 may be a multicast broadcast session management function (multicast/broadcast session management function, MB-SMF) network element, which is an SMF network element dedicated to managing multicast contexts, in which a TMGI of a multicast service is stored, together with a first IP multicast address and a C-TEID of a corresponding MB-UPF network element.

Wherein the TMGI is used in a multimedia broadcast multicast service (multimedia broadcast multicast service, MBMS) to uniquely identify the multicast and broadcast bearer service. The first IP multicast address is used for identifying multicast traffic transmitted by the MB-UPF network element, and the C-TEID is used for identifying a port of the MB-UPF network element.

PCF network element 107 is responsible for providing policies, such as QoS policies, slice selection policies, etc.

The UDM network element 108 is used for storing subscriber data such as subscription information, authentication/authorization information.

The AF network element 109, which may also be referred to as a server, is responsible for providing services to the 3GPP network, such as affecting service routing, interacting with PCF network elements for policy control, etc.

The AUSF network element 110 is used to authenticate and authorize the user.

NSSF network element 111 is used to centrally manage the slice functions.

Some concepts related to the present application are described below.

QoS flow: as shown in fig. 2, in a communication system (e.g., a 5G communication system), data may be transferred through a data session (e.g., PDU session) between terminal devices, RAN network elements, UPF network elements. Traffic data flows are carried and differentiated management is achieved in PDU sessions by quality of service (quality of service, qoS) flows (flows), each QoS flow being uniquely identified by a QoS flow identification (QoS flow identifier, QFI). QoS flows may be preconfigured by the SMF network element or may be established by a PDU session establishment procedure or PDU session modification procedure. QoS flows are transported between the RAN network element and the UPF network element through a user plane generic radio packet service tunneling protocol (GTP-U) tunnel. And mapping the QoS flow to corresponding air interface resources when the QoS flow is transmitted between the terminal equipment and the RAN network element.

I-frame and P-frame: the QoS streaming packets of a video stream (e.g., XR traffic) include intra-coded picture (I) frames and forward predictive-coded picture (P) frames, and the I frames and P frames are transmitted alternately. The I-frame is an intra-coded image frame, is an independent frame with all information, and can be independently decoded without reference to other images, thus being a key frame. P frame is the forward predictive coding image frame, which represents the difference between the current frame image and the previous frame image, and the difference between the current frame image and the previous frame image is overlapped by the previous frame image when decoding, so as to generate the current frame image. The amount of data for I frames is greater than the amount of data for P frames and the QoS requirements for I frames are different from P frames.

Base layer and enhancement layer: scalable video coding (scalable video coding, SVC) can divide a video stream into a base layer and a plurality of enhancement layers according to requirements, the base layer provides the most basic video quality, frame rate and resolution for a user, the enhancement layers further enhance the video quality, and the more SVC layers the user receives, the higher the video quality is obtained.

The PDU set may be data such as a media frame (frame), a media slice (slice), or a media block (tile), wherein the PDU set may include an I-frame and a P-frame, or a base layer and an enhancement layer, or video, audio, and haptic, etc.

As described above, there may be a dependency relationship between PDU sets mapped to different QoS flows, for example, the second PDU set depends on the first PDU set, the first PDU set is mapped to the first QoS flow, the second PDU set is mapped to the second QoS flow, if the first PDU set fails to be transmitted, the second PDU set cannot be decoded due to lack of the first PDU set which is relied upon even if the first PDU set is successfully transmitted, and at this time, transmission of the second PDU set may result in waste of transmission resources.

For example, in a video stream of a service stream, a certain GoP structure is an IPPP frame, where decoding of a P frame depends on parsing of an I frame (P frame depends on I frame for short), and parsing of a subsequent P frame depends on parsing of a previous P frame (P frame depends on previous P frame for short). For another example, the base layer and the enhancement layer are included in one video stream of one service stream, and in this case, the resolution of the enhancement layer depends on the resolution of the base layer (the enhancement layer depends on the base layer for short). For another example, the plurality of terminals commonly serve the same user, and the plurality of terminals respectively receive video (corresponding to video service), audio (corresponding to audio service), haptic (corresponding to perception service) and other types of data streams, that is, the plurality of terminals receive different service streams, at this time, the output of audio and haptic depends on the display of video (audio and haptic depend on video for short), or the display of video, the output of audio and haptic are not necessarily (i.e., video, audio, haptic depend on each other), and so on.

To this end, the embodiments of the present application provide a communication method, for a first PDU set and a second PDU set from the same AS, when the transmission of the first PDU set fails, the UPF network element or the RAN network element determines whether to continue to transmit the second PDU set according to a dependency relationship between the second PDU set and the first PDU set.

For example, in a video stream of a service stream, if the transmission of an I frame fails, a P frame dependent on the I frame cannot be resolved even if the transmission is successful, and transmission resources can be saved without transmitting the P frame. For another example, in a video stream of a service stream, if the base layer fails to transmit, the enhancement layer depending on the base layer cannot be resolved even if the transmission is successful, and transmission resources can be saved without transmitting the enhancement layer. For another example, the plurality of terminals respectively receive the video, the audio and the touch sense, if the video transmission fails, the user cannot obtain the complete experience even though the audio and the touch sense of the video are output depending on the output, and transmission resources can be saved without transmitting the audio and the touch sense; or, any one of the video, the audio and the touch is not transmitted successfully, the user cannot obtain the complete experience, and transmission resources can be saved by not transmitting the other two data.

In a communication method, when a UPF network element fails to transmit a first PDU set to a RAN network element, determining, by the UPF network element, whether to continue transmitting a second PDU set to the RAN network element according to a dependency relationship between the second PDU set and the first PDU set, as shown in fig. 3, the communication method includes:

s101, the UPF network element receives, from the AS, a first set of PDUs of a first service for use at the terminal device and a second set of PDUs of a second service for use at the terminal device.

The first service and the second service may be the same service or different services. The first set of PDUs and the second set of PDUs are from the same AS. The second set of PDUs is dependent on the first set of PDUs. The QoS requirements of the first PDU set are different from the QoS requirements of the second PDU set, or the importance of the first PDU set is different from the importance of the second PDU set.

The dependency referred to in this application may be that the second set of PDUs needs to depend on the first set of PDUs at decoding time, e.g. the first set of PDUs is an I-frame and the second set of PDUs is a P-frame, then the second set of PDUs depends on the first set of PDUs. The second set of PDUs is the enhancement layer and the first set of PDUs is the base layer, the second set of PDUs being dependent on the first set of PDUs. The present application may also refer to a dependency on service usage or display, for example, where the first set of PDUs corresponds to a video stream, and the second set of PDUs is audio or haptic, and if the video transmission fails, the experience of audio and haptic is incomplete, and thus the second set of PDUs is considered to be dependent on the first set of PDUs. For traffic usage or display dependencies, the set of PDUs corresponding to any data stream may be the first set of PDUs, while the set of PDUs corresponding to other data streams are the second set of PDUs. When any data stream is not successfully transmitted, the experience is incomplete due to the transmission of other data streams. Thus, the PDU sets corresponding to the data flows using the same service can be considered to be interdependent. The services of the present application may be media services (e.g., video, audio), perceptual services (e.g., haptic), etc.

The UPF network element may obtain the dependency relationship between the first PDU set and the second PDU set in a number of ways. For example, the AS may indicate, when sending the first set of PDUs and the second set of PDUs to the UPF network element, a dependency relationship between the first set of PDUs and the second set of PDUs directly by the indication information, e.g. by the indication information, the second set of PDUs being dependent on the first set of PDUs. Alternatively, the UPF network element may obtain a dependency relationship between the first PDU set and the second PDU set by detecting attribute information (attribute) of the first PDU set and the second PDU set, where the attribute information of the PDU set may include: i-frames and P-frames, or base and enhancement layers, or video, audio, and haptic, etc. For example, P frames depend on I frames belonging to the same GoP, P frames later in time depend on P frames earlier in time, enhancement layers depend on base layers, audio, haptic depend on video, or video, audio and haptic inter-depend, etc.

Thus, the first set of PDUs may be I frames in the video stream, and the second set of PDUs may be P frames belonging to the same GoP as the I frames. Alternatively, the first set of PDUs may be P frames in the video stream that are earlier in time sequence, and the second set of PDUs may be P frames that are later in time sequence in the same group as the earlier-time sequence P frames. Alternatively, the first set of PDUs is a base layer in the video stream and the second set of PDUs is an enhancement layer in the video stream. Alternatively, the first set of PDUs is one of video, audio, or haptic serving the same user, and the second set of PDUs is the remaining at least one of video, audio, haptic; illustratively, the first set of PDUs is video and the second set of PDUs is audio and/or haptic.

The UPF network element may map the first PDU set and the second PDU set to different QoS flows according to different attribute information of the first PDU set and the second PDU set.

For example, for an I frame and a P frame belonging to the same GoP, the UPF network element maps the I frame to a first QoS flow and the P frame to a second QoS flow. For another example, for multiple P frames belonging to the same GoP, the UPF network element maps the top-ordered P frame to a first QoS flow and the bottom-ordered P frame to a second QoS flow. For another example, for the base layer and the enhancement layer, the UPF network element maps the base layer to a first QoS flow and the enhancement layer to a second QoS flow.

In addition, the UPF network element distributes the identification of the first PDU set for the first PDU set, distributes the identification of the second PDU set for the second PDU set, and stores the dependency relationship between the first PDU set and the second PDU set.

When the UPF network element allocates identities of PDU sets for PDU sets with a dependency relationship, the identities of the PDU sets may be allocated based on QoS flow granularity, i.e. the identities of PDU sets mapped to the same QoS flow are different, the identities of PDU sets mapped to different QoS flows may be the same, in other words, the identities of the first PDU set may be the same or different from the identities of the second PDU set.

The UPF network element correlates the identifier QFI1 of the first QoS flow, the identifier of the first PDU set, the identifier QFI2 of the second QoS flow and the identifier of the second PDU set to obtain a first association relation, records the dependency relation between the first PDU set and the second PDU set, and therefore achieves the purpose of storing the dependency relation between the first PDU set and the second PDU set. Further, the UPF network element may determine (identities of) a second set of PDUs mapped to a second QoS flow in dependence of the first set of PDUs from the identities QFI of the first QoS flow and the identities of the first set of PDUs.

Or, when the UPF network element allocates the identities of the PDU sets for the PDU sets with the dependency relationship, the identities of the PDU sets may be allocated based on the granularity of the service flows, that is, the identities of the PDU sets of the same service flow are different, and are irrelevant to which QoS flow is mapped, and the identities of the first PDU set are different from the identities of the second PDU set. At this time, the UPF network element may assign the same association identifier to the first QoS flow and the second QoS flow, i.e. the association identifier may be used to identify QoS flows of the same traffic flow. At this time, the UPF network element associates the association identifier, the identifier of the first PDU set and the identifier of the second PDU set to obtain a second association relationship, and records the dependency relationship between the first PDU set and the second PDU set, thereby realizing the storage of the dependency relationship between the first PDU set and the second PDU set. Further, the UPF network element may determine (the identity of) the second PDU set dependent on the first PDU set based on the association identity and the identity of the first PDU set.

S102, the UPF network element sends a first PDU set to the RAN network element.

The UPF network element transmits a first PDU set to the RAN network element through a first QoS flow, and the RAN network element receives the first PDU set accordingly. The (packet header of the) GTP-U data packet carrying the first PDU set comprises the identity QFI1 of the first QoS flow and the identity of the first PDU set, or the (packet header of the) GTP-U data packet carrying the first PDU set comprises the association identity and the identity of the first PDU set.

It should be noted that, for the requirements of periodic resource configuration or discontinuous reception of connection state of the terminal device (connected mode discontinuous reception, CDRX), the RAN network element expects to receive data periodically, but there may be a time deviation between multiple PDU sets received by the UPF network element (for example, the AS is not strictly periodically transmitting PDU sets). When the UPF network element transmits the PDU set to the RAN network element, the time interval for transmitting the PDU set is determined according to the frame rate of the received PDU set or the frame rate of the PDU set is automatically detected to determine the time interval for transmitting the PDU set, so that the PDU set is periodically transmitted to the RAN network element. Thus, if the transmission time point of the next period is not reached, the UPF network element may delay transmitting the first set of PDUs to the RAN network element until the transmission time point of the next period. That is, for a periodically transmitted PDU set, if the UPF network element receives the PDU set in advance, buffering is first performed, and the PDU set is retransmitted by delaying to a transmission time point of the next period, so as to realize periodic transmission of the PDU set.

S103, the RAN network element sends a first PDU set to the terminal equipment.

And S104, responding to the transmission failure of the first PDU set, and sending a failure indication message to the UPF network element by the RAN network element.

The RAN network element may determine that the transmission of the first PDU set failed, e.g., the terminal device feeding back that the first PDU set was not received, the RAN network element failed to allocate resources for the first PDU set, etc.

The failure indication message is used to indicate that the first set of PDUs failed to be transmitted. For example, the first PDU set transmission failure may be indicated by the entire message or by some cell in the message.

In a possible implementation manner, if in step S104, the RAN network element receives, from the UPF network element, an identifier QFI1 of the first QoS flow and an identifier of the first PDU set, the failure indication message includes the identifier of the first QoS flow and the identifier of the first PDU set, which are used to instruct the UPF network element to determine the second PDU set according to the first PDU set.

In another possible implementation manner, if in step S104, the RAN network element receives the association identifier and the identifier of the first PDU set from the UPF network element, the failure indication message includes the association identifier and the identifier of the first PDU set, which are used to instruct the first device to determine the second PDU set according to the first PDU set. This embodiment corresponds to the UPF network element allocating the identity of the PDU set based on the traffic flow granularity.

S105, if the transmission of the first PDU set fails, the UPF network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set.

As described in step S104, the UPF network element may find the first association relationship stored in step S101 and the dependency relationship between the first PDU set and the second PDU set according to the identity QFI of the first QoS flow and the identity of the first PDU set in the failure indication message, determine the (identity of the) second PDU set mapped to the second QoS flow depending on the first PDU set, or the UPF network element may find the (identity of the) second PDU set depending on the first PDU set according to the association identity in the failure indication message and the identity of the first PDU set, and find the second association relationship stored in step S101 and the dependency relationship between the first PDU set and the second PDU set.

The UPF network element determines whether to resend the first PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set. If the first set of PDUs is relied upon by other sets of PDUs (e.g., the second set of PDUs), e.g., the first set of PDUs is an I frame, or the first set of PDUs is a P frame with a forward timing, or the first set of PDUs is a base layer, or the first set of PDUs is video, the UPF network element resends the first set of PDUs to the RAN network element. In addition, when congestion occurs on the air interface, the UPF network element may decide whether to resend the first PDU set to the RAN network element according to a delivery rule, a local configuration, or the like.

Optionally, in response to the periodic resource configuration or the CDRX requirement of the terminal device, the RAN network element expects that the received data is periodic, so if the transmission time point of the next period is not reached, the UPF network element may delay to the transmission time point of the next period to retransmit the first PDU set to the RAN network element.

The UPF network element may not resend the first set of PDUs to the RAN network element if the first set of PDUs is not relied upon by other sets of PDUs (e.g., the second set of PDUs).

The UPF network element further determines whether to send a second set of PDUs to the RAN network element:

if the UPF network element does not retransmit the first PDU set to the RAN network element, the UPF network element does not transmit the second PDU set to the RAN network element. Because the second PDU set depends on the first PDU set, even if the UPF network element sends the second PDU set, the second PDU set cannot be resolved correctly by the terminal device, which wastes transmission resources.

If the UPF network element re-transmits the first PDU set to the RAN network element, the UPF network element may transmit a second PDU set to the RAN network element. Further, if the UPF network element resends the first PDU set to the RAN network element, the UPF network element may further obtain air interface congestion information of the RAN network element, and determine whether to send the second PDU set to the RAN network element according to the air interface congestion information of the RAN network element and/or according to attribute information of the second PDU set.

The air interface congestion information may be from a RAN network element or an SMF network element, or the UPF network element may determine the air interface congestion information of the RAN network element through a transmission delay obtained by QoS Monitoring (QM), for example, the transmission delay is increased to indicate that the air interface is congested.

Specifically, if the air interface congestion information indicates that the air interface of the RAN network element is not congested, the UPF network element may send a second PDU set to the RAN network element. If the air interface congestion information indicates that an air interface of the RAN network element is congested, the UPF network element may not send the second PDU set to the RAN network element, or the UPF network element may send the second PDU set to the RAN network element according to attribute information of the second PDU set, for example, if the air interface of the RAN network element is congested, but the second PDU set is a P frame with a forward timing sequence, the UPF network element still sends the second PDU set to the RAN network element.

Optionally, in response to the periodic resource configuration or the CDRX requirement of the terminal device, the RAN network element expects that the received data is periodic, so if the transmission time point of the next period is not reached, the UPF network element delays to the transmission time point of the next period to send the second PDU set to the RAN network element.

In addition, if the UPF network element determines not to send the second PDU set to the RAN network element, the UPF network element sends dormancy indication information to the RAN network element, and the dormancy indication information is forwarded to the terminal equipment by the RAN network element. The dormancy indication information is used for indicating that the second PDU set is not sent to the terminal equipment at N periodic sending time points in the future, wherein N is the number of the second PDU sets cached in a period of time, so that the terminal equipment can carry out dormancy in the period of time, and does not need to receive downlink data so as to reduce power consumption.

According to the communication method provided by the embodiment of the application, when the UPF network element determines that the transmission of the first PDU set transmitted by the RAN network element to the terminal equipment fails, whether the second PDU set is transmitted to the RAN network element is determined according to the dependency relationship between the second PDU set and the first PDU set, so that the problem that the second PDU set is transmitted under any condition but cannot be analyzed correctly is avoided, transmission resources are wasted, and therefore the transmission resources can be saved.

In another communication method, a UPF network element maps a first PDU set and a second PDU set into different QoS flows, stores a dependency relationship between the second PDU set and the first PDU set, and transmits the dependency relationship to a RAN network element. When the RAN network element transmits the first PDU set to the terminal equipment and fails to transmit, the RAN network element determines whether to continue transmitting the second PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set so as to save transmission resources. As shown in fig. 4, the communication method includes:

s201, the UPF network element receives the first PDU set and the second PDU set from the AS.

This step refers to step S101, and will not be described in detail here.

S202, the UPF network element transmits a first PDU set to the RAN network element through a first QoS flow, and transmits a second PDU set to the RAN network element through a second QoS flow.

Accordingly, the RAN network element receives the first set of PDUs and the second set of PDUs from the UPF network element. The first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow. Other contents regarding the first PDU set, the second PDU set, the first QoS flow and the second QoS flow are described with reference to the foregoing, and will not be repeated herein.

The UPF network element may send the dependency relationship between the first PDU set and the second PDU set to the RAN network element, including the following embodiments:

in one possible implementation, when the UPF network element is sending the first set of PDUs and the second set of PDUs to the RAN network element, the first set of PDUs may be included in (the header of) the GTP-U data packet carrying the first set of PDUs, and the second set of PDUs may be included in (the header of) the GTP-U data packet carrying the second set of PDUs. The first PDU set dependency information comprises an identification of a first QoS flow and an identification of a first PDU set. The second PDU set dependency information includes an identification of the first QoS flow, an identification of the second QoS flow, an identification of the first PDU set, and an identification of the second PDU set. The first PDU set dependency information and the second PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set.

Since the first PDU set is independent of other PDU sets, only the identification of the first QoS flow and the identification of the first PDU set need be included in the first PDU set dependency information. Since the second PDU set depends on the first PDU set, the second PDU set dependency information includes not only the identification of the second QoS flow and the identification of the second PDU set, but also the identification of the first QoS flow and the identification of the first PDU set.

At this time, when the UPF network element allocates the PDU set identifier for the PDU set with the dependency relationship, the PDU set identifier may be allocated based on the QoS flow granularity, or the PDU set identifier may be allocated based on the service flow granularity.

In another possible implementation, when the UPF network element is sending the first and second PDU sets to the RAN network element, the third PDU set dependency information may be included in (the header of) the GTP-U data packet carrying the first PDU set and the fourth PDU set dependency information may be included in (the header of) the GTP-U data packet carrying the second PDU set. Wherein the third PDU set dependency information includes an association identifier and an identifier of the first PDU set. The fourth PDU set dependency information includes an association identifier, an identifier of the first PDU set, and an identifier of the second PDU set.

The third and fourth PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set. Since the first PDU set is independent of other PDU sets, only the association identifier and the identifier of the first PDU set need be included in the first PDU set dependency information. Since the second PDU set depends on the first PDU set, the second PDU set dependency information includes not only the association identifier and the identifier of the second PDU set, but also the identifier of the first PDU set.

At this time, the UPF network element allocates the PDU set identifier based on the service flow granularity when allocating the PDU set identifier for the PDU set with the dependency relationship.

Alternatively, the SMF network element or the UPF network element may send a dependency between the first QoS flow and the second QoS flow to the RAN network element, and since the second QoS flow depends on the first QoS flow, the set of PDUs mapped to the second QoS flow also depends on the set of PDUs mapped to the first QoS flow. Further, the (packet header of the) GTP-U data packet carrying the first PDU set and the (packet header of the) GTP-U data packet carrying the second PDU set also include the same group identifier; or (the packet header of) the GTP-U data packet carrying the second PDU set further comprises the identification of the first PDU set, and optionally (the packet header of) the GTP-U data packet carrying the first PDU set further comprises the identification of the second PDU set. Indicating that the second set of PDUs is dependent on the first set of PDUs.

The UPF network element sends the dependency relationship between the first QoS flow and the second QoS flow to the RAN network element, including the following embodiments:

in one possible implementation, when the UPF network element is sending the first set of PDUs and the second set of PDUs to the RAN network element, the first QoS flow dependency information may be included in (the header of) the GTP-U data packets carrying the first set of PDUs and the second QoS flow dependency information may be included in (the header of) the GTP-U data packets carrying the second set of PDUs. The first QoS flow dependence information comprises an identifier of a first QoS flow and first dependence indication information, and optionally, the first QoS flow dependence information also comprises an identifier of a second QoS flow. The second QoS flow dependency information includes an identifier of the first QoS flow, an identifier of the second QoS flow, and second dependency indication information. The first dependency indication information is used for indicating that the PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used for indicating that the PDU set mapped to the second QoS flow is dependent on other PDU sets, and the first QoS flow dependency information and the second QoS flow dependency information are used for indicating that the second QoS flow is dependent on the first QoS flow.

In another possible implementation, when the UPF network element is sending the first set of PDUs and the second set of PDUs to the RAN network element, the third QoS flow dependency information may be included in (the header of) the GTP-U data packets carrying the first set of PDUs and the fourth QoS flow dependency information may be included in (the header of) the GTP-U data packets carrying the second set of PDUs. The third QoS flow dependence information comprises an identifier of the first QoS flow, an association identifier and first dependence indication information, and the fourth QoS flow dependence information comprises an identifier of the second QoS flow, an association identifier and second dependence indication information. The first dependency indication information is used for indicating that the PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used for indicating that the PDU set mapped to the second QoS flow is dependent on other PDU sets, and the third QoS flow dependency information and the fourth QoS flow dependency information are used for indicating that the second QoS flow is dependent on the first QoS flow.

The first dependency indication information and the second dependency indication information related to the present application may be represented by different values of the same field, for example, a value of 1 in the field represents the first dependency indication information, a value of 0 in the field represents the second dependency indication information, or a value of 1 in the field represents the second dependency indication information, and a value of 0 in the field represents the first dependency indication information. The third and fourth PDU set dependency information indicates that the second QoS flow depends on the first QoS flow, i.e. that a second set of PDUs corresponding to the same group (e.g. same gos) as the second QoS flow transmission also depends on a first set of PDUs of the same group (e.g. same gos) as the first QoS flow transmission.

The SMF network element sends the dependency between the first QoS flow and the second QoS flow to the RAN network element:

the SMF network element sends a first QoS flow configuration message and a second QoS flow configuration message to the RAN network element, wherein the first QoS flow configuration message comprises first QoS flow dependence information, the second QoS flow configuration message comprises second QoS flow dependence information, or the first QoS flow configuration message comprises third QoS flow dependence information, and the second QoS flow configuration message comprises fourth QoS flow dependence information.

S203, the RAN network element sends a first PDU set to the terminal equipment.

S204, if the transmission of the first PDU set fails, the RAN network element determines whether to send the second PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set.

How the RAN network element can determine the transmission failure of the first PDU set refers to step S104, which is not described here.

The RAN network element may determine that the second PDU set depends on the first PDU set based on the first PDU set dependency information and the second PDU set dependency information. Alternatively, the RAN network element may determine that the second PDU set depends on the first PDU set based on the third PDU set dependency information and the fourth PDU set dependency information.

Alternatively, the RAN network element may determine that the second QoS flow depends on the first QoS flow according to the first QoS flow dependency information and the second QoS flow dependency information, and further determine that the second PDU set mapped to the second QoS flow belongs to the same group as the first PDU set through the group identification, so that the second PDU set may be determined to depend on the first PDU set. Or, the RAN network element determines that the second PDU set depends on the first PDU set through the identifier of the first PDU set carried in (the packet header of) the GTP-U data packet carrying the first PDU set and the identifier of the second PDU set carried in (the packet header of) the GTP-U data packet carrying the second PDU set.

Alternatively, the RAN network element may determine that the second QoS flow depends on the first QoS flow according to the third QoS flow dependency information and the fourth QoS flow dependency information, and further determine that the second PDU set mapped to the second QoS flow belongs to the same group as the first PDU set through the group identification, so that the second PDU set may be determined to depend on the first PDU set. Or, the RAN network element determines that the second PDU set depends on the first PDU set through the identifier of the first PDU set carried in (the packet header of) the GTP-U data packet carrying the first PDU set and the identifier of the second PDU set carried in (the packet header of) the GTP-U data packet carrying the second PDU set.

The RAN network element determines whether to resend the first PDU set to the terminal device according to the dependency relationship between the second PDU set and the first PDU set. If the first set of PDUs is relied upon by other sets of PDUs (e.g., the second set of PDUs), e.g., the first set of PDUs is an I frame, or the first set of PDUs is a P frame with a forward timing, or the first set of PDUs is a base layer, or the first set of PDUs is video, the RAN network element re-sends the first set of PDUs to the terminal device. The RAN network element may not resend the first set of PDUs to the terminal device if the first set of PDUs is not relied upon by other sets of PDUs (e.g., the second set of PDUs). In addition, when the air interface is congested, the RAN network element may decide whether to send the first PDU set to the terminal device again according to a delivery rule, a local configuration, and so on, so as to ensure the normal communication of the network preferentially.

The RAN network element further determines whether to send a second set of PDUs to the terminal device:

if the RAN network element determines not to re-send the first PDU set to the terminal device, the RAN does not send the second PDU set to the terminal device. Because the second set of PDUs depends on the first set of PDUs, even if the RAN sends the second set of PDUs, it cannot be properly parsed by the terminal device, wasting transmission resources.

The RAN may send the second set of PDUs to the terminal device if the RAN resends the first set of PDUs to the terminal device. Further, if the RAN network element re-sends the first PDU set to the terminal device, the RAN network element may further determine whether to send the second PDU set to the terminal device according to air interface congestion information of the RAN network element and/or according to attribute information of the second PDU set.

Specifically, if the air interface congestion information indicates that the air interface is not congested, the RAN network element may send a second PDU set to the terminal device. If the air interface congestion information indicates that the air interface is congested, the RAN network element may not send the second PDU set to the terminal device, or the RAN network element may send the second PDU set to the terminal device according to attribute information of the second PDU set, if the air interface of the RAN network element is congested, but the second PDU set is a P frame with a front timing sequence, the RAN network element still sends the second PDU set to the terminal device.

According to the communication method provided by the embodiment of the application, when the RAN network element determines that the transmission of the first PDU set transmitted to the terminal equipment fails, whether the second PDU set is transmitted to the terminal equipment is determined according to the dependency relationship between the second PDU set and the first PDU set, so that the situation that the second PDU set is transmitted under any condition and cannot be analyzed correctly is avoided, transmission resources are wasted, and therefore the transmission resources can be saved.

The technical scheme of the present application is described in detail below in connection with specific embodiments.

Fig. 5 is a specific embodiment of the communication method shown in fig. 3 in the present application, in which the UPF network element maps the first PDU set and the second PDU set into different QoS flows, and stores the dependency relationship between the second PDU set and the first PDU set. After the UPF network element sends the first PDU set to the RAN network element, if the indication information of the transmission failure of the first PDU set is received from the RAN network element, the UPF network element may not send the second PDU set any more according to the dependency relationship, so as to save transmission resources.

Specifically, as shown in fig. 5, the communication method includes steps S301 to S310.

S301, the AF network element sends to the PCF network element the QoS requirements of the first set of PDUs and the QoS requirements of the second set of PDUs of the traffic flow (e.g. video flow).

The present application is described by taking the example that the QoS requirement of the first PDU set is higher than that of the second PDU set, but is not intended to be limited thereto. For example, for an I frame and a P frame belonging to the same GoP, the first PDU set is an I frame and the second PDU set is a P frame, the QoS requirement of the I frame is higher than the QoS requirement of the P frame (e.g., the bandwidth requirement of the I frame is higher than the bandwidth requirement of the P frame). For another example, for multiple P frames belonging to the same GoP, the first set of PDUs is a forward-ordered P frame and the second set of PDUs is a backward-ordered P frame, where the QoS requirement of the forward-ordered P frame is higher than the QoS requirement of the backward-ordered P frame (e.g., the scheduling priority requirement of the forward-ordered P frame is higher than the scheduling priority requirement of the backward-ordered P frame). For another example, for the base layer and the enhancement layer, the first set of PDUs is the base layer and the second set of PDUs is the enhancement layer, with the QoS requirement of the base layer being higher than the QoS requirement of the enhancement layer (e.g., the error rate of the base layer being less than the error rate of the enhancement layer).

Since the QoS requirements of the first PDU set and the QoS requirements of the second PDU set are different, the first PDU set and the second PDU set may be mapped to different QoS flows.

Illustratively, the AF network element sends to the PCF network element the QoS requirements of I frames (first PDU set) and the QoS requirements of P frames (second PDU set) of the same GoP in the video stream.

S302, the PCF network element sends policy and charging control (policy and charging control, PCC) rules (rule) to the SMF network element.

The QoS requirements of the first set of PDUs and the QoS requirements of the second set of PDUs are included in the PCC rules. In the prior art, because the data of the same service flow is basically mapped to the same QoS flow, the AF network element issues QoS parameters for the service flow, and does not issue QoS parameters for the QoS flow. Thus, the PCC rule may also indicate that all QoS flows of the traffic flow (i.e. the first QoS flow and the second QoS flow referred to herein) share a certain QoS parameter, e.g. that all QoS flows of the traffic flow share guaranteed bit rate (guaranteed bit rate, GBR) bandwidth, etc.

Illustratively, the PCC rules include QoS requirements for I frames (first set of PDUs) and QoS requirements for P frames (second set of PDUs) of the same GoP in the video stream.

S303, the SMF network element sends the mapping rule to the UPF network element.

The mapping rule is used to instruct the UPF network element to map the first set of PDUs and the second set of PDUs to different QoS flows, respectively.

Illustratively, the mapping rule instructs the UPF network element to map an I-frame (first set of PDUs) in the video stream to a first QoS stream (indicated by associating the I-frame with an identification QFI1 of the first QoS stream), and to map a P-frame (second set of PDUs) belonging to the same GoP as the I-frame to a second QoS stream (indicated by associating the P-frame with an identification QFI2 of the second QoS stream).

The mapping rules may be carried in an N4 rule (N4 rule) that indicates how the UPF network element processes the received data flow.

Optionally, the N4 rule further includes first processing indication information, configured to instruct the UPF network element to determine whether to send the second PDU set to the RAN network element according to a dependency relationship between the second PDU set and the first PDU set. Illustratively, the first process indication information may be indicated by a one bit value of 1: the UPF network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set. The first processing instruction information may be indicated by the bit having a value of 0: the UPF network element does not have to determine whether to send the second set of PDUs to the RAN network element based on the dependency between the second set of PDUs and the first set of PDUs.

S304, the SMF network element sends the first QoS flow configuration message and the second QoS flow configuration message to the RAN network element.

The SMF network element distributes an identifier QFI1 of the first QoS flow to the first QoS flow, and distributes an identifier QFI2 of the second QoS flow to the second QoS flow. The first QoS flow meets a higher QoS requirement than the second QoS flow. The first QoS flows a first PDU set with higher QoS requirements, and the second QoS flows a second PDU set with lower QoS requirements.

The first QoS flow configuration message and the second QoS flow configuration message may be an N2 message (N2 message), for example. The first QoS flow configuration message includes configuration information of the first QoS flow, such as an identification QFI1 of the first QoS flow, and/or QoS parameters (located in a QoS profile) of the first QoS flow. The second QoS flow configuration message includes configuration information for the second QoS flow, such as an identification QFI2 of the second QoS flow, and/or QoS parameters (located in the QoS configuration file) for the second QoS flow.

Optionally, if the PCC rule in step S302 indicates that all QoS flows of the service flow share a certain QoS parameter, the first QoS flow configuration message and the second QoS flow configuration message further include sharing indication information and a QoS parameter, where the sharing indication information is used to indicate that the first QoS flow and the second QoS flow share the QoS parameter, otherwise the first QoS flow configuration message and the second QoS flow configuration message do not include sharing indication information. For example, assuming that I, P frames belonging to one video stream are mapped to a first QoS stream and a second QoS stream, respectively, the two QoS streams can be indicated to commonly use 10M of bandwidth by sharing indication information, and if the two QoS streams are indicated to have 10M of bandwidth without sharing indication information, the video stream occupies 20M of bandwidth in total, which is likely to cause congestion of transmission resources.

The shared indication information in the first QoS flow configuration message and the second QoS flow configuration message may be the same QoS parameter association identifier. Or the sharing indication information in the first QoS flow configuration message is the identifier QFI2 of the second QoS flow, and the sharing indication information in the second QoS flow configuration message is the identifier QFI1 of the first QoS flow.

S305, the AS sends the first PDU set and the second PDU set to the UPF network element.

Illustratively, the AS sends an I-frame (first set of PDUs) and a P-frame (second set of PDUs) of the same GoP in the video stream to the UPF network element.

S306, the UPF network element maps the first PDU set to the first QoS flow according to different attribute information of the first PDU set and the second PDU set, maps the second PDU set to the second QoS flow, and stores the dependency relationship between the first PDU set and the second PDU set.

The UPF network element may obtain the dependency relationship between the first PDU set and the second PDU set in a plurality of manners, specifically referring to step S101.

Illustratively, the UPF network element maps I frames (first PDU set) to a first QoS flow and P frames (second PDU set) to a second QoS flow according to the I frames and P frames of the same GoP in the video flow, and stores the dependency relationship between the I frames (first PDU set) and the P frames (second PDU set) (P frames depend on the I frames).

The other contents of this step refer to step S101, and are not described here again.

S307, the UPF network element transmits a first PDU set to the RAN network element through a first QoS flow.

Illustratively, the UPF network element transmits I frames (a first set of PDUs) in the video stream to the RAN network element over a first QoS stream.

The other contents of this step refer to step S102, and are not described herein.

S308, the RAN network element sends the first PDU set to the terminal device.

Illustratively, the RAN network element sends an I-frame (first set of PDUs) in the video stream to the terminal device.

S309, if the transmission of the first PDU set fails, the RAN network element sends a failure indication message to the UPF network element.

Illustratively, if the transmission of an I-frame (first set of PDUs) in the video stream fails, the RAN network element sends a failure indication message to the UPF network element.

The other contents of this step refer to step S104, and are not described herein.

S310, if the transmission of the first PDU set fails, the UPF network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set.

Illustratively, if the transmission of an I-frame (first set of PDUs) in the video stream fails, the UPF network element determines whether to send a P-frame (second set of PDUs) to the RAN network element depending on the I-frame from the P-frame of the same GoP. For example, if the UPF network element determines to resend the I frame to the RAN network element, the UPF network element may send the P frame to the RAN network element, or if the UPF network element determines to resend the I frame to the RAN network element, and if the RAN network element air interface is not congested, the UPF network element may send the P frame to the RAN network element.

The other contents of this step refer to step S105, and are not described here again.

Fig. 6 is a specific embodiment of the communication method shown in fig. 3 in this application, where, for a scenario such AS periodic resource configuration or discontinuous reception of connection states of terminal devices (connected mode discontinuous reception, CDRX), the data that the RAN network element expects to receive is periodic, but there may be a time offset between multiple PDU sets received by the UPF network element (e.g., the AS is not strictly a periodic issuing PDU set). When the UPF network element transmits the PDU set to the RAN network element, the time interval for transmitting the PDU set is determined according to the frame rate of the received PDU set or the frame rate of the PDU set is automatically detected to determine the time interval for transmitting the PDU set, so that the PDU set is periodically transmitted to the RAN network element.

Specifically, as shown in fig. 6, the communication method includes steps S401 to S410, wherein steps S401 to S406 refer to steps S301 to S306 in fig. 5.

S407, if the transmission time point of the next period is not reached, the UPF network element delays to the transmission time point of the next period and transmits the first PDU set to the RAN network element through the first QoS flow.

By way of example, assuming that the period (or time interval) in which the UPF network element transmits I frames and P frames in the video stream to the RAN network element is 20ms, the transmission time points of the respective periods are 20ms, 40ms, 60ms, and so on. If the current time is 30ms, the UPF network element delays sending I frames in the video stream to 40 ms.

S408, the RAN network element sends the first PDU set to the terminal equipment.

S409, if the transmission of the first PDU set fails, the RAN network element sends a failure indication message to the UPF network element.

S410, if the transmission of the first PDU set fails, the UPF network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set.

As described in step S105, if the UPF network element determines to resend the first PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set, and if the sending time point of the next period is not reached, the UPF network element may delay to resend the first PDU set to the RAN network element by the sending time point of the next period.

Illustratively, assuming that the period (or time interval) of the UPF network element transmitting the I-frames and the P-frames in the video stream to the RAN network element is 20ms, the transmission time points of each period are 20ms, 40ms, 60ms, 80ms, and so on. If the transmission of the I frame (first PDU set) fails after the transmission of the I frame (first PDU set) in the video stream for 40ms and the current time is 50ms, the UPF network element delays to 60ms to re-transmit the I frame (first PDU set) in the video stream to the RAN network element and transmits the P frame (second PDU set) of the same GoP to the RAN network element at 60ms according to the original transmission cadence.

If the UPF network element determines not to send the second PDU set to the RAN network element, the UPF network element sends dormancy indication information to the RAN network element, and the dormancy indication information is forwarded to the terminal equipment by the RAN network element. The sleep indication information is referred to the foregoing description and will not be described herein.

The other contents of this step refer to steps S105 and S310, and are not described in detail herein.

Fig. 7 is a specific embodiment of the communication method shown in fig. 4 in the present application, in which the UPF network element maps the first PDU set and the second PDU set into different QoS flows, stores a dependency relationship between the second PDU set and the first PDU set, and sends the dependency relationship to the RAN network element through the first PDU set dependency information and the second PDU set dependency information. Or sending the dependency relationship to the RAN network element through the third PDU set dependency information and the fourth PDU set dependency information. After the RAN network element schedules the first PDU set, if the transmission of the first PDU set is determined to fail, whether to continue to transmit the second PDU set to the terminal equipment is determined according to the dependency relationship so as to save transmission resources. The first PDU set dependency information, the second PDU set dependency information, the third PDU set dependency information and the fourth PDU set dependency information are described above, and will not be described again.

Specifically, as shown in fig. 7, the communication method includes steps S501 to S509.

S501, the AF network element sends to the PCF network element the QoS requirements of the first set of PDUs and the QoS requirements of the second set of PDUs of the traffic flow (e.g. video flow).

The other contents of this step refer to step S301, and will not be described here again.

S502, the PCF network element sends PCC rules to the SMF network element.

The other contents of this step refer to step S302, and are not described herein.

S503, the SMF network element sends a mapping rule to the UPF network element.

Optionally, the N4 rule further includes second processing instruction information, configured to instruct the UPF network element to send a dependency relationship between the second PDU set and the first PDU set to the RAN network element, where the RAN network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set.

Illustratively, the second process indication information may be indicated by a field having a value of 1: the UPF network element transmits the dependency relationship between the second PDU set and the first PDU set to the RAN network element. The second process instruction information may be indicated by the value of 0 in this field: the UPF network element does not have to send the dependency between the second set of PDUs and the first set of PDUs to the RAN network element.

S504, the SMF network element sends a first QoS flow configuration message and a second QoS flow configuration message to the RAN network element.

Optionally, the first QoS flow configuration message or the second QoS flow configuration message further includes third processing indication information, configured to indicate whether the RAN network element determines whether to send the second PDU set to the RAN network element according to a dependency relationship between the second PDU set and the first PDU set.

Illustratively, the third process indication information may be indicated by a field having a value of 1: the RAN network element determines whether to send the second PDU set to the RAN network element according to the dependency relationship between the second PDU set and the first PDU set. The third processing instruction information may be indicated by the value of 0 in this field: the RAN network element does not have to determine whether to send the second set of PDUs to the RAN network element based on a dependency relationship between the second set of PDUs and the first set of PDUs.

The other contents of this step refer to step S304, and are not described herein.

S505, the AS sends the first PDU set and the second PDU set to the UPF network element.

S506, the UPF network element maps the first PDU set to the first QoS flow according to different attribute information of the first PDU set and the second PDU set, maps the second PDU set to the second QoS flow, and stores the dependency relationship between the first PDU set and the second PDU set.

This step refers to step S101, and will not be described in detail here.

S507, the UPF network element transmits a first PDU set to the RAN network element through a first QoS flow, transmits a second PDU set to the RAN network element through a second QoS flow, and transmits a dependency relationship between the first PDU set and the second PDU set to the RAN network element.

The (packet header of the) GTP-U data packet carrying the first PDU set comprises first PDU set dependency information, and the (packet header of the) GTP-U data packet carrying the second PDU set comprises second PDU set dependency information; or (the packet header of) the GTP-U data packet carrying the first PDU set comprises third PDU set dependency information, and (the packet header of) the GTP-U data packet carrying the second PDU set comprises fourth PDU set dependency information. And thereby send the RAN network element a dependency relationship between the first set of PDUs and the second set of PDUs.

Illustratively, the UPF network element transmits I frames (first set of PDUs) in the video stream to the RAN network element over a first QoS flow and P frames (second set of PDUs) of the same GoP to the RAN network element over a second QoS flow. The (packet header of the) GTP-U data packet bearing the I frame comprises the identification of the first QoS flow and the identification of the I frame, and the (packet header of the) GTP-U data packet bearing the P frame comprises the identification of the first QoS flow, the identification of the second QoS flow, the identification of the I frame and the identification of the P frame; or (the packet header of) the GTP-U data packet bearing the I frame comprises an association identifier and an identifier of the I frame, and (the packet header of) the GTP-U data packet bearing the P frame comprises an association identifier, an identifier of the I frame and an identifier of the P frame. Thus sending the RAN network element a dependency between the I-frames and the P-frames (P-frames in the same gos depend on the I-frames).

The first PDU set dependency information, the second PDU set dependency information, the third PDU set dependency information and the fourth PDU set dependency information are referred to the related description in step S202, and are not described herein.

S508, the RAN network element sends the first PDU set to the terminal equipment.

S509, if the transmission of the first PDU set fails, the RAN network element determines whether to send the second PDU set to the terminal device according to the dependency relationship between the second PDU set and the first PDU set.

Illustratively, if the transmission of an I-frame (first set of PDUs) in the video stream fails, the RAN network element determines whether to send a P-frame (second set of PDUs) to the terminal device depending on the I-frame from the P-frame of the same GoP. For example, the RAN network element determines to resend the I frame to the terminal device, the RAN network element may send the P frame to the terminal device, or the RAN network element determines to resend the I frame to the terminal device, and the RAN network element air interface is not congested, the RAN network element may send the P frame to the terminal device.

The other contents of this step refer to step S204, and are not described herein.

Fig. 8 is another embodiment of the communication method shown in fig. 3 in the present application, which differs from the embodiment shown in fig. 7 in that: the RAN network element obtains the first QoS flow dependence information and the second QoS flow dependence information from the SMF network element or the UPF network element, or obtains the third QoS flow dependence information and the fourth QoS flow dependence information from the SMF network element or the UPF network element, thereby determining that the second QoS flow depends on the first QoS flow. The RAN network element further determines that the second set of PDUs mapped to the second QoS flow belongs to the same group as the first set of PDUs by means of the group identity, so that it may be determined that the second set of PDUs is dependent on the first set of PDUs. Or, the RAN network element determines that the second PDU set depends on the first PDU set through the identifier of the first PDU set carried in (the packet header of) the GTP-U data packet carrying the first PDU set and the identifier of the second PDU set carried in (the packet header of) the GTP-U data packet carrying the second PDU set. The first QoS flow dependency information, the second QoS flow dependency information, the third QoS flow dependency information, and the fourth QoS flow dependency information are described above, and are not described here.

Specifically, as shown in fig. 8, the communication method includes steps S601 to S609, wherein steps S601 to S603 refer to steps S301 to S303 in fig. 5:

s604, the SMF network element sends a first QoS flow configuration message and a second QoS flow configuration message to the RAN network element.

As described in step S304, the SMF network element allocates an identifier QFI1 of the first QoS flow to the first QoS flow and allocates an identifier QFI2 of the second QoS flow to the second QoS flow.

Optionally, the SMF network element sends a dependency between the first QoS flow and the second QoS flow to the RAN network element:

in one possible implementation, the SMF network element determines the first dependency indication information and the second dependency indication information. The first QoS flow configuration message includes first QoS flow dependency information, and the second QoS flow configuration message includes second QoS flow dependency information, so that a dependency relationship between the first QoS flow and the second QoS flow is sent to the RAN network element. Namely, the first QoS flow configuration message comprises a mark QFI1 of a first QoS flow and first dependency indication information, and optionally, the first QoS flow configuration message also comprises a mark QFI2 of a second QoS flow; the second QoS flow configuration message includes an identification QFI2 of the second QoS flow, an identification QFI1 of the first QoS flow, and second dependency indication information.

The first dependency indicator and the second dependency indicator may be represented by different values of the same field, e.g. a field value of 1 for the first dependency indicator and a field value of 0 for the second dependency indicator, or a field value of 1 for the second dependency indicator and a field value of 0 for the first dependency indicator.

Alternatively, in another possible implementation, the SMF network element determines the first dependency indication information and the second dependency indication information and assigns the same association identifier to the first QoS flow and the second QoS flow. The first QoS flow configuration message includes third QoS flow dependency information, and the second QoS flow configuration message includes fourth QoS flow dependency information, so that a dependency relationship between the first QoS flow and the second QoS flow is sent to the RAN network element. Namely, the first QoS flow configuration message comprises an identifier QFI1 of the first QoS flow, an association identifier and first dependency indicating information, and the second QoS flow configuration message comprises an identifier QFI1 of the second QoS flow, an association identifier and second dependency indicating information.

The first dependency indication information, the second dependency indication information, the association identifier, the first QoS flow dependency information, the second QoS flow dependency information, the third QoS flow dependency information, and the fourth QoS flow dependency information are referred to the relevant description in step S202, and are not described in detail herein.

The other contents of step S604 refer to step S304, and are not described herein.

S605, the AS sends the first PDU set and the second PDU set to the UPF network element.

S606, the UPF network element maps the first PDU set to the first QoS flow according to different attribute information of the first PDU set and the second PDU set, maps the second PDU set to the second QoS flow, and stores the dependency relationship between the first PDU set and the second PDU set.

The UPF network element distributes the identification of the first PDU set for the first PDU set, distributes the identification of the second PDU set for the second PDU set, and can distribute the identification of the PDU set based on the granularity of the service flow when distributing the identification of the PDU set for the PDU set with the dependency relationship.

Alternatively, if in S604 the SMF network element does not send the dependency relationship between the first QoS flow and the second QoS flow to the RAN network element, then the UPF network element determines the first dependency indication information and the second dependency indication information. Further alternatively, the UPF network element may assign the same association identifier to the first QoS flow and the second QoS flow.

The other contents of this step refer to step S306, and are not described herein.

S607, the UPF network element sends the first PDU set to the RAN network element through the first QoS flow, and sends the second PDU set to the RAN network element through the second QoS flow.

The (header of the) GTP-U data packet carrying the first PDU set includes the identity of the first QoS flow, the identity of the first PDU set. The (header of the) GTP-U data packet carrying the second PDU set includes the identity of the second QoS flow, the identity of the second PDU set.

Illustratively, the UPF network element transmits I frames (first set of PDUs) in the video stream to the RAN network element over a first QoS flow and P frames (second set of PDUs) of the same GoP to the RAN network element over a second QoS flow. The (header of the) GTP-U data packet carrying the I frame includes the identification of the first QoS flow and the identification of the I frame, and the (header of the) GTP-U data packet carrying the P frame includes the identification of the second QoS flow and the identification of the P frame.

Optionally, if in S604 the SMF network element does not send the dependency between the first QoS flow and the second QoS flow to the RAN network element, the UPF network element sends the dependency between the first QoS flow and the second QoS flow to the RAN network element.

In a possible implementation, the (header of the) GTP-U data packet carrying the first PDU set includes the first QoS flow dependency information, and the (header of the) GTP-U data packet carrying the second PDU set also includes the second QoS flow dependency information. Or (the packet header of) the GTP-U data packet carrying the first PDU set includes third QoS flow dependency information, and (the packet header of) the GTP-U data packet carrying the second PDU set also includes fourth QoS flow dependency information.

The (header of the) GTP-U data packet carrying the I frame further includes an identifier of the first QoS flow, first dependency indication information, and optionally further includes an identifier of the second QoS flow, and the (header of the) GTP-U data packet carrying the P frame further includes an identifier of the first QoS flow, an identifier of the second QoS flow, and second dependency indication information.

Or the (packet header of the) GTP-U data packet bearing the I frame also comprises the identification, the association identification and the first dependency indication information of the first QoS flow, and the (packet header of the) GTP-U data packet bearing the P frame comprises the identification, the association identification and the second dependency indication information of the second QoS flow.

In addition, a group identifier (e.g. a GoP identifier) may be included in (the header of) the GTP-U data packet carrying the first PDU set and in (the header of) the GTP-U data packet carrying the second PDU set, to indicate that the first PDU set and the second PDU set belong to the same group. Or (the packet header of) the GTP-U data packet carrying the first PDU set further comprises the identification of the second PDU set, and (the packet header of) the GTP-U data packet carrying the second PDU set further comprises the identification of the first PDU set. Indicating that the second set of PDUs is dependent on the first set of PDUs.

Illustratively, the (header of the) GTP-U data packet carrying the I frame and the (header of the) GTP-U data packet carrying the P frame also include the golp identification. Or, the (packet header of the) GTP-U data packet carrying the I frame further includes the identification of the P frame, and the (packet header of the) GTP-U data packet carrying the P frame includes the identification of the I frame.

S608, the RAN network element sends the first PDU set to the terminal device.

S609, if the transmission of the first PDU set fails, the RAN network element determines whether to send the second PDU set to the terminal device according to the dependency relationship between the second PDU set and the first PDU set.

As shown in fig. 9, an embodiment of the present application provides a communication apparatus 900, including a processor 910. Optionally, the communication device 900 further comprises a memory 930. Processor 910 is coupled to memory 930, and memory 930 is configured to store instructions. When the communication device 900 is used to implement the methods described above, the processor 910 is configured to execute instructions in the memory 930 to implement the functions described above with respect to fig. 3-8.

Optionally, the communication device 900 further comprises an interface circuit 920. The processor 910 and the interface circuit 920 are coupled to each other. It is understood that the interface circuit 920 may be a transceiver or an input-output interface for communicating with other communication devices.

Illustratively, when the communication device 900 is a chip applied to a RAN network element, a UPF network element, or an SMF network element, the chip implements the functions of the RAN network element, the UPF network element, or the SMF network element in the above method embodiments. The chip receives information from other modules (such as radio frequency modules or antennas) in the RAN network element, the UPF network element and the SMF network element, and the information is sent to the RAN network element, the UPF network element and the SMF network element by other devices; or the chip sends information to other modules (such as radio frequency modules or antennas) in the RAN network element, the UPF network element and the SMF network element, and the information is sent to other devices by the RAN network element, the UPF network element and the SMF network element.

As shown in fig. 10, the embodiment of the application further provides a chip system. The system on a chip 1000 includes at least one processor 1010 and at least one interface circuit 1020. The at least one processor 1010 and the at least one interface circuit 1020 may be interconnected by wires. The processor 1010 is configured to support a communication device to implement the steps of the method embodiments described above, e.g., the methods illustrated in fig. 3-8, and at least one interface circuit 1020 may be configured to receive signals from other devices (e.g., memory) or to transmit signals to other devices (e.g., a communication interface). The system-on-chip may include a chip, and may also include other discrete devices.

It will be appreciated that in the above embodiments, the methods and/or steps implemented by the RAN network element may also be implemented by a component (e.g., a chip or a circuit) that may be used in the RAN network element, and the methods and/or steps implemented by the UPF network element may also be implemented by a component that may be used in the UPF network element.

The above description has been presented mainly from the point of interaction between the network elements. Correspondingly, the embodiment of the application also provides a communication device which is used for realizing the various methods. The communication device may be a RAN network element or a UPF network element in the above method embodiment, or a device comprising the RAN network element or the UPF network element, or a component usable with the RAN network element or the UPF network element. It will be appreciated that the communication device, in order to achieve the above-described functions, comprises corresponding hardware structures and/or software modules performing the respective functions. Those of skill in the art will readily appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. 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.

In the embodiment of the present application, the functional modules of the communication device may be divided according to the above embodiment of the method, for example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated modules may be implemented in hardware or in software functional modules. It should be noted that, in the embodiment of the present application, the division of the modules is schematic, which is merely a logic function division, and other division manners may be implemented in actual implementation.

For example, the communication device is taken as an example of a RAN network element or a UPF network element in the foregoing method embodiment. Fig. 11 shows a schematic structural diagram of a communication device 1100. The communication device 1100 comprises a processing module 1101 and a transceiver module 1102. The transceiver module 1102, which may also be referred to as a transceiver unit, is configured to perform a transmitting and/or receiving function, and may be, for example, a transceiver circuit, a transceiver, or a communication interface.

When the communication device 1100 is a UPF network element:

in a possible implementation, the transceiver module 1102 is configured to receive a first set of protocol data units, PDUs, of a first service used at the terminal device and a second set of PDUs of a second service used at the terminal device, where the first set of PDUs and the second set of PDUs are mapped to different quality of service, qoS, flows; and sending the first PDU set to the access network element. The processing module 1101 is configured to determine whether to send the second PDU set to the access network element according to a dependency relationship between the second PDU set and the first PDU set if the transmission of the first PDU set fails.

In a possible implementation manner, the processing module 1101 is configured to control the transceiver module 1102 to resend the first PDU set to the access network element according to a dependency relationship between the second PDU set and the first PDU set, and determine whether to send the second PDU set to the access network element.

In a possible implementation manner, the processing module 1101 is configured to obtain air interface congestion information of a network element of an access network; and determining whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element and/or according to the attribute information of the second PDU set.

In a possible implementation manner, the transceiver module 1102 is configured to receive air interface congestion information from an access network element or a session management function network element, or obtain the air interface congestion information through QoS monitoring.

In a possible implementation manner, the transceiver module 1102 is configured to send a second PDU set to the access network element if the air interface congestion information indicates that the air interface of the access network element is not congested; or if the air interface congestion information indicates that the air interface of the access network element is congested, sending the second PDU set to the access network element according to the attribute information of the second PDU set.

In a possible implementation manner, the transceiver module 1102 is configured to delay to the transmission time point of the next period to resend the first PDU set to the access network element if the transmission time point of the next period is not reached.

In a possible implementation manner, the transceiver module 1102 is configured to delay to the transmission time point of the next period to send the second PDU set to the access network element if the transmission time point of the next period is not reached.

In a possible implementation manner, the transceiver module 1102 is configured to send dormancy indication information to the access network element if it is determined that the second PDU set is not to be sent to the access network element, where the dormancy indication information is used to indicate that the second PDU set is not to be sent to the terminal device at N periodic sending time points in the future, and N is the number of second PDU sets that are buffered in a period of time.

In one possible implementation, the first PDU set is mapped to a first QoS flow, and the data packet carrying the first PDU set includes an identifier of the first QoS flow and an identifier of the first PDU set; the transceiver module 1102 is configured to receive a failure indication message from an access network element, where the failure indication message includes an identifier of a first QoS flow and an identifier of a first PDU set, the failure indication message is configured to indicate that transmission of the first PDU set fails, and the received identifier of the first QoS flow and the received identifier of the first PDU set are configured to instruct a user plane functional network element to determine a second PDU set according to the first PDU set.

In one possible implementation manner, the data packet carrying the first PDU set includes an identifier of the first PDU set and an association identifier of the first PDU set, which corresponds to the second PDU set together; the transceiver module 1102 is configured to receive a failure indication message from an access network element, where the failure indication message includes an association identifier and an identifier of a first PDU set, the failure indication message is configured to indicate that transmission of the first PDU set fails, and the received association identifier and the identifier of the first PDU set are configured to instruct a user plane functional network element to determine a second PDU set according to the first PDU set.

When the communication device 1100 is a RAN network element:

in a possible implementation manner, the transceiver module 1102 is configured to receive, from a user plane function network element, a first set of protocol data units PDU of a first service used at a terminal device and a second set of PDUs of a second service used at the terminal device, where the first set of PDUs and the second set of PDUs are mapped to different quality of service QoS flows; transmitting a first PDU set to a terminal device; the processing module 1101 is configured to determine whether to send the second PDU set to the terminal device according to a dependency relationship between the second PDU set and the first PDU set if the transmission of the first PDU set fails.

In a possible implementation manner, the processing module 1101 is configured to control the transceiver module 1102 to resend the first PDU set to the terminal device according to a dependency relationship between the second PDU set and the first PDU set, and determine whether to send the second PDU set to the terminal device.

In a possible implementation manner, the processing module 1101 is configured to determine whether to send the second PDU set to the terminal device according to air interface congestion information and/or according to attribute information of the second PDU set.

In a possible implementation manner, the first PDU set is mapped to a first QoS flow, the second PDU set is mapped to a second QoS flow, and the transceiver module 1102 is configured to receive the first QoS flow dependency information and the second QoS flow dependency information from the session management function network element, or the data packet carrying the first PDU set includes the first QoS flow dependency information, and the data packet carrying the second PDU set includes the second QoS flow dependency information; the first QoS flow dependency information includes an identifier of the first QoS flow, first dependency indication information, and second QoS flow dependency information, where the first dependency indication information is used to indicate that a PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that a PDU set mapped to the second QoS flow is dependent on other PDU sets, and the first QoS flow dependency information and the second QoS flow dependency information are used to indicate that the second QoS flow is dependent on the first QoS flow.

In a possible implementation manner, the transceiver module 1102 is configured to receive third QoS flow dependency information and fourth QoS flow dependency information from a session management function network element, or the data packet carrying the first PDU set includes the third QoS flow dependency information, and the data packet carrying the second PDU set includes the fourth QoS flow dependency information; the third QoS flow dependency information includes an identifier of the first QoS flow, an association identifier, and first dependency indication information, the fourth QoS flow dependency information includes an identifier of the second QoS flow, an association identifier, and second dependency indication information, where the first dependency indication information is used to indicate that the PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that the PDU set mapped to the second QoS flow is dependent on other PDU sets, and the third QoS flow dependency information and the fourth QoS flow dependency information are used to indicate that the second QoS flow depends on the first QoS flow.

In one possible implementation, the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, and the transceiver module 1102 is configured to receive configuration information of the first QoS flow, where the configuration information of the first QoS flow includes sharing indication information and QoS parameters, and the sharing indication information is configured to indicate that the first QoS flow and the second QoS flow share QoS parameters.

Embodiments also provide a computer readable storage medium comprising instructions that, when executed on a communication device as described above, cause the communication device to perform the steps of the method embodiments described above, for example, performing the methods shown in fig. 3-8.

Embodiments of the present application also provide a computer program product comprising instructions which, when run on the above-described communication device, cause the communication device to perform the steps of the above-described method embodiments, for example, performing the methods shown in fig. 3-8.

Technical effects concerning the chip system, the computer-readable storage medium, the computer program product refer to the technical effects of the previous method embodiments.

The processor referred to in the embodiments of the present application may be a chip. For example, it may be a field programmable gate array (field programmable gate array, FPGA), an application specific integrated circuit (application specific integrated circuit, ASIC), a system on chip (SoC), a central processing unit (central processor unit, CPU), a network processor (network processor, NP), a digital signal processor (digital signal processor, DSP), a micro control unit (micro controller unit, MCU), a programmable logic device (programmable logic device, PLD), or other integrated chip.

The memory to which embodiments of the present application relate may be volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile 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. The volatile memory may be random access memory (random access memory, RAM) which acts as an external cache. By way of example, and not limitation, many forms of RAM are available, such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous DRAM (SLDRAM), and direct memory bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

It should be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application.

Those of ordinary skill in the art will appreciate that the various illustrative modules 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 solution. 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 will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described system, apparatus and module may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, e.g., the division of the modules is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple modules or components may be combined or integrated into another device, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, indirect coupling or communication connection of devices or modules, electrical, mechanical, or other form.

The modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physically separate, i.e., may be located in one device, or may be distributed over multiple devices. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional module in each embodiment of the present application may be integrated in one device, or each module may exist alone physically, or two or more modules may be integrated in one device.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using a software program, it 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. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. 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 a wired (e.g., coaxial cable, fiber optic, digital subscriber line (Digital Subscriber Line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device including one or more servers, data centers, etc. that can be integrated with the medium. The usable medium may be a magnetic medium (e.g., a floppy Disk, a hard Disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a Solid State Disk (SSD)), or the like.

The foregoing is merely 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 about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to 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 of communication, comprising:

receiving a first set of protocol data units, PDUs, of a first service for use at a terminal device and a second set of PDUs of a second service for use at the terminal device, wherein the first set of PDUs and the second set of PDUs are mapped to different quality of service, qoS, flows;

transmitting the first PDU set to an access network element;

and if the transmission of the first PDU set fails, determining whether to send the second PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set.

2. The method of claim 1, wherein the determining whether to send the second set of PDUs to the access network element based on the dependency relationship between the second set of PDUs and the first set of PDUs comprises:

And re-sending the first PDU set to the access network element according to the dependency relationship between the second PDU set and the first PDU set, and determining whether to send the second PDU set to the access network element.

3. The method of claim 2, wherein the determining whether to send the second set of PDUs to the access network element comprises:

acquiring air interface congestion information of the access network element;

and determining whether to send the second PDU set to the access network element according to the air interface congestion information of the access network element and/or according to the attribute information of the second PDU set.

4. A method according to claim 3, wherein said obtaining air interface congestion information of the access network element comprises:

and receiving the air interface congestion information from the access network element or the session management function network element, or obtaining the air interface congestion information through QoS monitoring.

5. The method according to claim 3 or 4, wherein said determining whether to send the second set of PDUs to the access network element according to air interface congestion information of the access network element and/or according to attribute information of the second set of PDUs comprises:

If the air interface congestion information indicates that the air interface of the access network element is not congested, the second PDU set is sent to the access network element;

or,

and if the air interface congestion information indicates that the air interface of the access network element is congested, sending the second PDU set to the access network element according to the attribute information of the second PDU set.

6. The method according to any of claims 2-5, wherein said resending the first set of PDUs to the access network element comprises:

and if the transmission time point of the next period is not reached, delaying to the transmission time point of the next period to resend the first PDU set to the access network element.

7. The method according to any of claims 2-6, wherein said sending the second set of PDUs to the access network element comprises:

and if the sending time point of the next period is not reached, delaying the sending time point of the next period to send the second PDU set to the access network element.

8. The method of any one of claims 1-7, further comprising:

and if the second PDU set is not transmitted to the access network element, transmitting dormancy indication information to the access network element, wherein the dormancy indication information is used for indicating that the second PDU set is not transmitted to the terminal equipment at N periodic transmission time points in the future, and N is the number of the second PDU sets cached in a period of time.

9. The method according to any of claims 1-8, wherein the first set of PDUs is mapped to a first QoS flow, wherein the data packets carrying the first set of PDUs include an identification of the first QoS flow and an identification of the first set of PDUs; the method further comprises the steps of:

and receiving a failure indication message from the access network element, wherein the failure indication message comprises an identifier of the first QoS flow and an identifier of the first PDU set, the failure indication message is used for indicating that the transmission of the first PDU set fails, and the received identifier of the first QoS flow and the received identifier of the first PDU set are used for indicating a user plane function network element to determine the second PDU set according to the first PDU set.

10. The method according to any of claims 1-9, wherein the data packet carrying the first PDU set includes an identification of the first PDU set and an association identification of the first PDU set that corresponds together with the second PDU set; the method further comprises the steps of:

and receiving a failure indication message from the access network element, wherein the failure indication message comprises the association identifier and the identifier of the first PDU set, the failure indication message is used for indicating that the transmission of the first PDU set fails, and the received association identifier and the received identifier of the first PDU set are used for indicating a user plane function network element to determine the second PDU set according to the first PDU set.

11. The method according to any one of claims 1 to 10, wherein,

the first PDU set is an I frame in a video stream, and the second PDU set is a P frame which is the same group as the I frame;

or the first PDU set is a P frame with a front time sequence in the video stream, and the second PDU set is a P frame with a rear time sequence which is the same as the P frame with the front time sequence;

or the first PDU set is a base layer in the video stream, and the second PDU set is an enhancement layer in the video stream;

alternatively, the first set of PDUs is one of video, audio, or haptic to serve the same user, and the second set of PDUs is the remaining at least one of video, audio, haptic.

12. A method of communication, comprising:

receiving a first set of protocol data units, PDUs, of a first service for use at a terminal device and a second set of PDUs of a second service for use at the terminal device from a user plane functional network element, wherein the first set of PDUs and the second set of PDUs are mapped to different quality of service, qoS, flows;

transmitting the first PDU set to the terminal equipment;

and if the transmission of the first PDU set fails, determining whether to send the second PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set.

13. The method of claim 12, wherein the determining whether to send the second set of PDUs to the terminal device based on the dependency relationship between the second set of PDUs and the first set of PDUs comprises:

and re-transmitting the first PDU set to the terminal equipment according to the dependency relationship between the second PDU set and the first PDU set, and determining whether to transmit the second PDU set to the terminal equipment.

14. The method of claim 13, wherein the determining whether to send the second set of PDUs to the terminal device comprises:

and determining whether to send the second PDU set to the terminal equipment according to the air interface congestion information and/or the attribute information of the second PDU set.

15. The method of any of claims 12-14, wherein the first set of PDUs is mapped to a first QoS flow, wherein the second set of PDUs is mapped to a second QoS flow,

the data packet carrying the first PDU set comprises first PDU set dependency information, the first PDU set dependency information comprises the identification of the first QoS flow and the identification of the first PDU set,

the data packet carrying the second PDU set comprises second PDU set dependency information, wherein the second PDU set dependency information comprises the identification of the first QoS flow, the identification of the second QoS flow, the identification of the first PDU set and the identification of the second PDU set;

The first PDU set dependency information and the second PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set.

16. The method according to any one of claims 12 to 14, wherein,

the data packet carrying the first PDU set comprises third PDU set dependency information, wherein the third PDU set dependency information comprises an association identifier and an identifier of the first PDU set;

the data packet carrying the second PDU set comprises fourth PDU set dependency information, wherein the fourth PDU set dependency information comprises the association identifier, the identifier of the first PDU set and the identifier of the second PDU set;

the third PDU set dependency information and the fourth PDU set dependency information are used to indicate that the second PDU set depends on the first PDU set.

17. The method of any of claims 12-14, wherein the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising:

receiving first QoS flow dependence information and second QoS flow dependence information from a session management function network element, or carrying the first QoS flow dependence information in a data packet of the first PDU set and the second QoS flow dependence information in a data packet of the second PDU set;

The first QoS flow dependency information includes an identifier of the first QoS flow and first dependency indication information, the second QoS flow dependency information includes an identifier of the first QoS flow, an identifier of the second QoS flow and second dependency indication information, the first dependency indication information is used for indicating that a PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used for indicating that a PDU set mapped to the second QoS flow depends on other PDU sets, and the first QoS flow dependency information and the second QoS flow dependency information are used for indicating that the second QoS flow depends on the first QoS flow.

18. The method of claim 17 wherein the first QoS flow dependency information further includes an identification of the second QoS flow.

19. The method of any of claims 12-14, wherein the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising:

receiving third QoS flow dependence information and fourth QoS flow dependence information from a session management function network element, or, the third QoS flow dependence information is included in a data packet bearing the first PDU set, and the fourth QoS flow dependence information is included in a data packet bearing the second PDU set;

The third QoS flow dependency information includes an identifier of the first QoS flow, an association identifier, and first dependency indication information, and the fourth QoS flow dependency information includes an identifier of the second QoS flow, the association identifier, and second dependency indication information, where the first dependency indication information is used to indicate that a PDU set mapped to the first QoS flow is dependent on other PDU sets, the second dependency indication information is used to indicate that a PDU set mapped to the second QoS flow depends on other PDU sets, and the third QoS flow dependency information and the fourth QoS flow dependency information are used to indicate that the second QoS flow depends on the first QoS flow.

20. The method according to any one of claims 17 to 19, wherein,

the data packet carrying the first PDU set and the data packet carrying the second PDU set include group identifiers, or the data packet carrying the second PDU set also includes the identifiers of the first PDU set, so as to indicate that the second PDU set depends on the first PDU set.

21. The method of claim 20, wherein the data packet carrying the first set of PDUs further comprises an identification of the second set of PDUs.

22. The method of any of claims 12-21, wherein the first set of PDUs is mapped to a first QoS flow and the second set of PDUs is mapped to a second QoS flow, the method further comprising:

And receiving configuration information of a first QoS flow, wherein the configuration information of the first QoS flow comprises sharing indication information and QoS parameters, and the sharing indication information is used for indicating the first QoS flow and the second QoS flow to share the QoS parameters.

23. The method according to claim 22, wherein the sharing indication information is an association identity or an identity of the second QoS flow;

wherein the association identifies QoS flows for associating all shared QoS parameters.

24. The method according to any one of claims 12 to 23, wherein,

25. A method of communication, comprising:

transmitting the first PDU set to an access network element;

transmitting the first PDU set to the terminal equipment;

26. A method of communication, comprising:

transmitting a first set of protocol data units, PDU, of a first service used at a terminal device and a second set of PDUs of a second service used at the terminal device to an access network element, wherein the first set of PDUs and the second set of PDUs are mapped to different quality of service, qoS, flows;

transmitting the first PDU set to the terminal equipment;

27. A communication device comprising a processor and a memory, wherein the memory stores instructions that, when executed by the processor, perform the method of any of claims 1-26.

28. A communication system comprising the communication device of claim 27.

29. A computer readable storage medium comprising instructions which, when executed on a communication device, cause the communication device to perform the method of any of claims 1-26.