Time delay measurement method and related device

Abstract

Provided is a time delay measurement method, comprising: acquiring a first time delay and a second time delay of a first data packet, the first time delay being a time delay between a user plane device and a terminal device, and the second time delay being a time delay between the user plane device and an access network device; and determining a target time delay according to the first time delay and the second time delay, the target time delay being a time delay between the terminal device and the access network device. According to the scheme provided by the invention, when the air interface time delay is determined, the terminal equipment and the access network device do not need to specially send data packets carrying timestamps for multiple times for measurement, so that the overhead caused by measuring the air interface time delay is reduced, and the air interface capacity of the access network device and the terminal equipment is improved.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and particularly to a method for measuring delay and related devices thereof. Background Art

[0002] Due to some services that guarantee delay and reliability (such as ultra-reliable and low latency communication (URLLC)), there are relatively high requirements for quality of service (QoS). In practical applications, in order to ensure delay and reliability, devices in the network need to be able to timely sense the link quality and make corresponding adjustments.

[0003] Delay is a very important aspect of QoS. Through real-time measurement of delay, visual management of the QoS of URLLC services can be achieved. Currently, through QoS Monitoring, the measurement of the packet delay between a terminal device and a user plane function (UPF) in the core network can be completed, including the measurement of the up / down packet delay between the terminal device and the access network device (which can also be referred to as the air interface delay), and the measurement of the up / down packet delay between the access network device and the UPF.

[0004] Among them, if it is necessary to measure the air interface delay of each packet, it is required to send packets back and forth between the access network device and the terminal device, each time carrying a timestamp, with extremely high overhead, which affects the air interface capacity of the access network device and the terminal device. Summary of the Invention

[0005] This application provides a method for measuring delay, which is used to measure the air interface delay of each packet with relatively small overhead. This application also provides corresponding devices, systems, computer-readable storage media, computer program products, etc.

[0006] The first aspect of this application provides a method for measuring delay, including: obtaining a first delay and a second delay of a first packet, where the first delay is the delay between the user plane device and the terminal device, and the second delay is the delay between the user plane device and the access network device; determining a target delay according to the first delay and the second delay, where the target delay is the delay between the terminal device and the access network device.

[0007] The delay measurement method of this application can be applied to the delay measurement of various types of communication services, such as: URLLC services, but not limited to URLLC services, and can also be other types of communication services that need to measure the air interface delay.

[0008] In this application, the user plane device can be a device in the core network that can perform user plane functions, such as: a user plane function (UPF) network element. The access network device can be various types of base stations, and the terminal device can be a device with air interface transmission capabilities or a set including a device with air interface transmission capabilities and other devices.

[0009] In this application, the first delay can be the delay measured using the user plane protocol between the terminal device and the user plane device, such as: the delay between the terminal device and the user plane device measured through the performance measurement functionality (PMF) protocol. This delay can be the round trip time (RTT), uplink delay, or downlink delay between the terminal device and the user plane device, where RTT is also called round trip latency.

[0010] In this application, the second delay can be the delay between the user plane device and the access network device measured through the QoS Monitoring process. This delay can be the RTT, uplink delay, or downlink delay between the user plane device and the access network device.

[0011] In this application, the target delay can be the air interface delay between the terminal device and the access network device, and this target delay can be the difference between the first delay and the second delay.

[0012] In this application, the process of the first aspect above can be executed by the user plane device or by other devices in the core network. If it is executed by other devices, only the first delay and the second delay need to be obtained from the user plane device.

[0013] In this first aspect, for each data packet, the air interface delay between the terminal device and the access network device can be calculated by obtaining the first delay between the terminal device and the user plane device, and the second delay between the user plane device and the access network device, and then through the first delay and the second delay. This way of determining the air interface delay does not require the terminal device and the access network device to specifically send multiple data packets carrying timestamps for measurement, reducing the overhead brought by measuring the air interface delay, thereby improving the air interface capacity of the access network device and the terminal device.

[0014] In a possible implementation, the first delay is the round trip latency between the user plane device and the terminal device; the second delay is the round trip latency between the user plane device and the access network device; the target delay is the round trip latency between the terminal device and the access network device.

[0015] In this possible implementation manner, both the first time delay and the second time delay are RTTs, and the determined target time delay is also the RTT of the air interface. The RTT of the air interface can be obtained through the first time delay and the second time delay, reducing the overhead caused by measuring the RTT of the air interface.

[0016] In a possible implementation manner, the first time delay is the uplink time delay between the terminal device and the user plane device; the second time delay is the uplink time delay between the access network device and the user plane device; the target time delay is the uplink time delay between the terminal device and the access network device.

[0017] In this possible implementation manner, both the first time delay and the second time delay are uplink time delays, and the determined target time delay is also the uplink time delay of the air interface. The uplink time delay of the air interface can be obtained through the first time delay and the second time delay, reducing the overhead caused by measuring the uplink time delay of the air interface.

[0018] In a possible implementation manner, the first time delay is the downlink time delay between the user plane device and the terminal device; the second time delay is the downlink time delay between the user plane device and the access network device; the target time delay is the downlink time delay between the terminal device and the access network device.

[0019] In this possible implementation manner, both the first time delay and the second time delay are downlink time delays, and the determined target time delay is also the downlink time delay of the air interface. The downlink time delay of the air interface can be obtained through the first time delay and the second time delay, reducing the overhead caused by measuring the downlink time delay of the air interface.

[0020] In a possible implementation manner, obtaining the first time delay and the second time delay of the first data packet includes: the user plane device sends the first data packet, and the first data packet contains a first indication and a second indication. The first indication is used to instruct the access network device to perform quality of service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information, where the first information is related to the first time delay; the user plane device receives the first information and the second information, and the second information is the QoS monitoring information of the access network device. Here, the first information is used to determine the first time delay, and the second information is used to determine the second time delay.

[0021] In this possible implementation manner, for each data packet sent by the user plane device, it can carry the first indication and the second indication therein. The first indication can be a QoS monitoring indication, and the second indication can be an RTT indication, an uplink time delay indication, or a downlink time delay indication. In this application, through the first indication and the second indication, the user plane device can complete two measurements with one data packet, and can measure both the first time delay and the second time delay, thereby improving the accuracy of the air interface time delay measurement of a single data packet.

[0022] In a possible implementation, the first information and the second information of the first data packet have an associated relationship.

[0023] In this possible implementation, since the first information and the second information of the first data packet have an associated relationship, the user plane device or other network elements used to calculate the target delay can accurately calculate the first delay and the second delay of the same data packet based on this associated relationship, and then determine the corresponding air interface delay.

[0024] In a possible implementation, the first information and the second information are associated by a first identifier.

[0025] In this possible implementation, the first identifier can be a number or index used to mark the data packet sent by the user plane device, or other identifiers, such as: sequence number (SN). Associating the first information and the second information by an identifier can improve the calculation speed of the air interface delay.

[0026] In a possible implementation, the first information and the second information are included in the same message.

[0027] In this possible implementation, since the first information and the second information are included in the same message, after receiving the message, the user plane device can directly calculate the first delay and the second delay, and then obtain the air interface delay, without the need to search for the associated relationship, further improving the calculation speed of the air interface delay.

[0028] In a possible implementation, when the terminal device is associated with a device-side time sensitive network translator (DS-TT), the DS-TT connects to the terminal device, the first delay is the delay between the DS-TT and the user plane device, and the target delay is the delay between the terminal device and the access network device.

[0029] In this possible implementation, the DS-TT and the terminal device are usually connected by wire and there will also be a delay. In this case, the target delay can be the difference between the first delay and the second delay minus the delay between the DS-TT and the terminal device. For this scenario including the DS-TT and the terminal device, by further subtracting the delay between the DS-TT and the terminal device, the accuracy of the air interface delay can be improved.

[0030] In a possible implementation, the method further includes: obtaining a third delay between the user plane device and the application server; determining the delay between the terminal device and the application server according to the first delay and the third delay.

[0031] In this possible implementation, the latency between the terminal device and the application server can be the sum of the first latency and the third latency. Through this calculation, the end-to-end latency between the terminal device and the application server in the data network (DN) can be quickly determined.

[0032] In one possible implementation, the method further includes: the user plane device receives a per-packet QoS monitoring indication from the control plane device, and the per-packet QoS monitoring indication is used to instruct the user plane device to perform QoS monitoring on each sent data packet.

[0033] In this possible implementation, the per-packet QoS monitoring indication may be sent by the application function (AF), and may be gradually sent to the UPF through the Policy Control Function (PCF), the Session Management Function (SMF). Among them, the AF sends a segmented per-packet QoS monitoring indication, that is, it indicates that the latency between the user plane device and the access network device, the user plane device and the terminal device, and the access network device and the terminal device is measured for each data packet. By controlling the per-packet latency measurement through the AF, the requirements of the application can be better met.

[0034] The second aspect of this application provides a latency measurement method, including: the access network device receives a first data packet, the first data packet contains a first indication and a second indication, the first indication is used to instruct the access network device to perform Quality of Service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information; the access network device performs QoS monitoring between the access network device and the user plane device according to the first indication; the access network device sends the first data packet to the terminal device and receives the first information from the terminal device; the access network device sends the first information and second information to the user plane device, and the second information is the QoS monitoring information of the access network device, where the first information is used to determine a first latency, the second information is used to determine a second latency, the first latency is the latency between the user plane device and the terminal device, the second latency is the latency between the user plane device and the access network device, and the first latency and the second latency are used to determine a target latency, and the target latency is the latency between the terminal device and the access network device.

[0035] In this application, the access network device can perform QoS monitoring between the access network device and the user plane device according to a first indication, send a first data packet to the terminal device according to a second indication to complete the delay measurement between the terminal device and the user plane device, and then return first information and second information to the user plane device. The access network device does not need to measure the air interface delay between it and the terminal device. The user plane device can determine the air interface delay between the terminal device and the access network device according to the first information and the second information, thereby reducing the overhead caused by measuring the air interface delay and improving the air interface capacity of the access network device.

[0036] In a possible implementation, a third indication is included in the packet where the first information is located, and the third indication is used to instruct the access network device to add the second information to the packet where the first information is located; the access network device adds the second information to the packet where the first information is located according to the third indication.

[0037] In this possible implementation, when the terminal device returns the first information to the access network device, it can add a third indication to the packet where the first information is located to instruct the access network device to also add the second information to this packet, so that the access network device reports the first information and the second information to the user plane device through one packet.

[0038] A third aspect of this application provides a delay measurement method, including: the terminal device receives a first data packet, and the first data packet contains a second indication, and the second indication is used to instruct the terminal device to report first information; the terminal device determines the first information according to the second indication; the terminal device sends the first information to the access network device, and the first information is used to determine a first delay, and the first delay is the delay between the user plane device and the terminal device.

[0039] In this application, the terminal device only needs to return the first information to the access network device according to the second indication, and does not need to send packets carrying timestamps to the access network device multiple times for measuring the air interface delay, thereby reducing the overhead caused by measuring the air interface delay and improving the air interface capacity of the terminal device.

[0040] In a possible implementation, the method further includes: the terminal device adds a third indication to the packet where the first information is located, and the third indication is used to instruct the access network device to add the second information to the packet where the first information is located; the above step: the terminal device sends the first information to the access network device includes: the terminal device sends a packet containing the first information and the third indication to the access network device.

[0041] In this possible implementation, when the terminal device returns the first information to the access network device, it may add a third indication in the packet where the first information is located to instruct the access network device to also add the second information in the packet, so that the access network device reports the first information and the second information to the user plane device through one packet.

[0042] In a possible implementation, the second indication in the first data packet is a round-trip time (RTT) message; correspondingly, the first information is an RTT response message.

[0043] In a possible implementation, the second indication in the first data packet is used to indicate the transmission of an uplink synchronization packet; correspondingly, the packet containing the first information is an uplink synchronization packet.

[0044] In a possible implementation, the second indication in the first data packet is used to indicate the transmission of a downlink synchronization packet, and the downlink synchronization packet further includes a downlink delay indication, which is used to indicate that the terminal device reports the downlink delay between the user plane device and the terminal device; correspondingly, the first information is the downlink synchronization delay, and the first delay is the downlink delay between the user plane device and the terminal device.

[0045] In the above several implementations, the second indication indicates different contents in different forms, so that the terminal device returns the corresponding RTT response message, uplink synchronization packet, or downlink synchronization packet, thereby completing the measurement of RTT, uplink delay, or downlink delay.

[0046] A fourth aspect of this application provides a communication device, which includes a transceiver module and a processing module;

[0047] The processing module is configured to: obtain a first delay and a second delay of the first data packet, where the first delay is the delay between the user plane device and the terminal device, and the second delay is the delay between the user plane device and the access network device;

[0048] The processing module is further configured to determine a target delay according to the first delay and the second delay, where the target delay is the delay between the terminal device and the access network device.

[0049] In a possible implementation, the first delay is the round-trip delay between the user plane device and the terminal device; the second delay is the round-trip delay between the user plane device and the access network device; the target delay is the round-trip delay between the terminal device and the access network device.

[0050] In a possible implementation, the first delay is the uplink delay between the terminal device and the user plane device; the second delay is the uplink delay between the access network device and the user plane device; the target delay is the uplink delay between the terminal device and the access network device.

[0051] In a possible implementation, the first time delay is the downlink time delay between the user plane device and the terminal device; the second time delay is the downlink time delay between the user plane device and the access network device; the target time delay is the downlink time delay between the terminal device and the access network device.

[0052] In a possible implementation, a transceiver module is configured to send a first data packet, where the first data packet includes a first indication and a second indication. The first indication is used to instruct the access network device to perform Quality of Service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information, where the first information is related to the first time delay.

[0053] The transceiver module is further configured to receive the first information and second information. The second information is the QoS monitoring information of the access network device. Among them, the first information is used to determine the first time delay, and the second information is used to determine the second time delay.

[0054] In a possible implementation, the first information and the second information in the first data packet have an associated relationship.

[0055] In a possible implementation, the first information and the second information are associated through a first identifier.

[0056] In a possible implementation, the first information and the second information are included in the same message.

[0057] In a possible implementation, when the terminal device is associated with the DS-TT and the terminal device, the DS-TT connects to the terminal device. The first time delay is the time delay between the DS-TT and the user plane device, and the target time delay is the time delay between the terminal device and the access network device.

[0058] In a possible implementation, the transceiver module is further configured to obtain a third time delay between the user plane device and the application server.

[0059] The processing module is further configured to determine the time delay between the terminal device and the application server according to the first time delay and the third time delay.

[0060] In a possible implementation, the transceiver module is further configured to receive a per-packet QoS monitoring indication from the control plane device. The per-packet QoS monitoring indication is used to instruct the user plane device to perform QoS monitoring on each sent data packet.

[0061] A fifth aspect of the present application provides a communication device, which includes a transceiver module and a processing module.

[0062] The transceiver module is configured to receive a first data packet, where the first data packet includes a first indication and a second indication. The first indication is used to instruct the access network device to perform Quality of Service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information.

[0063] A processing module, configured to perform QoS monitoring between an access network device and a user plane device according to a first indication;

[0064] A transceiver module, further configured to send a first data packet to a terminal device and receive first information from the terminal device;

[0065] The transceiver module is further configured to send the first information and second information to the user plane device, where the second information is QoS monitoring information of the access network device. The first information is used to determine a first delay, the second information is used to determine a second delay, the first delay is the delay between the user plane device and the terminal device, the second delay is the delay between the user plane device and the access network device, and the first delay and the second delay are used to determine a target delay, where the target delay is the delay between the terminal device and the access network device.

[0066] In a possible implementation, the processing module is further configured to add the second information to the packet where the first information is located when a third indication included in the packet where the first information is located is used to indicate that the access network device adds the second information to the packet where the first information is located.

[0067] A sixth aspect of the present application provides a communication device, which includes a transceiver module and a processing module;

[0068] The transceiver module is configured to receive a first data packet, where the first data packet contains a second indication for indicating that the terminal device reports first information;

[0069] The processing module is configured to determine the first information according to the second indication;

[0070] The transceiver module is further configured to send the first information to the access network device, where the first information is used to determine a first delay, and the first delay is the delay between the user plane device and the terminal device.

[0071] In a possible implementation, the processing module is further configured to add a third indication to the packet where the first information is located, where the third indication is used to indicate that the access network device adds the second information to the packet where the first information is located;

[0072] The transceiver module is further configured to send a packet containing the first information and the third indication to the access network device.

[0073] In a possible implementation, the second indication in the first data packet is a round-trip time (RTT) message; correspondingly, the first information is an RTT response message.

[0074] In a possible implementation, the second indication in the first data packet is used to indicate sending an uplink synchronization packet; correspondingly, the packet containing the first information is an uplink synchronization packet.

[0075] In a possible implementation, the second indication in the first data packet is used to indicate the transmission of a downlink synchronization message, and the downlink synchronization message further includes a downlink delay indication, which is used to indicate the downlink delay between the user plane device and the terminal device reported by the terminal device; correspondingly, the first information is the downlink synchronization delay, and the first delay is the downlink delay between the user plane device and the terminal device.

[0076] The seventh aspect of the present application provides a communication device, which includes: a processor, a memory, and a transceiver. A computer program or computer instructions are stored in the memory, and the processor is used to call and run the computer program or computer instructions stored in the memory, so that the processor implements the operations processed in the first aspect and any implementation manner, and the transceiver is used to transmit and receive signals, such as: implementing the receiving operations in the first aspect and any implementation manner.

[0077] The eighth aspect of the present application provides a communication device, which includes: a processor, a memory, and a transceiver. A computer program or computer instructions are stored in the memory, and the processor is used to call and run the computer program or computer instructions stored in the memory, so that the processor implements the operations processed in the second aspect and any implementation manner, and the transceiver is used to transmit and receive signals, such as: implementing the receiving operations in the second aspect and any implementation manner.

[0078] The ninth aspect of the present application provides a communication device, which includes: a processor, a memory, and a transceiver. A computer program or computer instructions are stored in the memory, and the processor is used to call and run the computer program or computer instructions stored in the memory, so that the processor implements the operations processed in the third aspect and any implementation manner, and the transceiver is used to transmit and receive signals, such as: implementing the receiving operations in the third aspect and any implementation manner.

[0079] The tenth aspect of the present application provides a communication device, which includes a processor, and the processor is used to execute the first aspect and any implementation manner of the first aspect.

[0080] The eleventh aspect of the present application provides a communication device, which includes a processor, and the processor is used to execute the second aspect and any implementation manner of the second aspect.

[0081] The twelfth aspect of the present application provides a communication device, which includes a processor, and the processor is used to execute the third aspect and any implementation manner of the third aspect.

[0082] The thirteenth aspect of the present application provides a computer-readable storage medium, including computer instructions, which when running on a computer, cause the computer to execute the first aspect and any implementation manner.

[0083] The fourteenth aspect of the present application provides a computer-readable storage medium, including computer instructions, which, when running on a computer, cause the computer to execute the implementation manners of the second aspect and any one thereof.

[0084] The fifteenth aspect of the present application provides a computer-readable storage medium, including computer instructions, which, when running on a computer, cause the computer to execute the implementation manners of the third aspect and any one thereof.

[0085] The sixteenth aspect of the present application provides a computer program product including instructions, characterized in that when it runs on a computer, it causes the computer to execute the implementation manners of the first aspect and any one thereof.

[0086] The seventeenth aspect of the present application provides a computer program product including instructions, characterized in that when it runs on a computer, it causes the computer to execute the implementation manners of the second aspect and any one thereof.

[0087] The eighteenth aspect of the present application provides a computer program product including instructions, characterized in that when it runs on a computer, it causes the computer to execute the implementation manners of the third aspect and any one thereof.

[0088] The nineteenth aspect of the present application provides a chip device, including a processor, configured to call a computer program or computer instructions in the memory, so that the processor executes the implementation manners of the first aspect and any one thereof.

[0089] Optionally, the processor is coupled to the memory through an interface.

[0090] The twentieth aspect of the present application provides a chip device, including a processor, configured to call a computer program or computer instructions in the memory, so that the processor executes the implementation manners of the second aspect and any one thereof.

[0091] Optionally, the processor is coupled to the memory through an interface.

[0092] The twenty-first aspect of the present application provides a chip device, including a processor, configured to call a computer program or computer instructions in the memory, so that the processor executes the implementation manners of the third aspect and any one thereof.

[0093] Optionally, the processor is coupled to the memory through an interface.

[0094] The twenty-second aspect of the present application provides a communication system, which includes a terminal device, an access network device, and a user plane device. Among them, the user plane device is used to execute the above-mentioned first aspect and any implementation manner; the access network device is used to execute the above-mentioned second aspect and any implementation manner; the terminal device is used to execute the above-mentioned third aspect and any implementation manner.

[0095] For the technical effects of the fourth, seventh, tenth, thirteenth, sixteenth, nineteenth, and twenty-second aspects of the present application, reference can be made to the first aspect and the technical effects of any possible implementation manner of the first aspect for understanding.

[0096] For the technical effects of the fifth, eighth, eleventh, fourteenth, seventeenth, and twentieth aspects of the present application, reference can be made to the second aspect and the technical effects of any possible implementation manner of the second aspect for understanding.

[0097] For the technical effects of the sixth, ninth, twelfth, fifteenth, eighteenth, and twenty-first aspects of the present application, reference can be made to the third aspect and the technical effects of any possible implementation manner of the third aspect for understanding. Description of the Drawings

[0098] Figure 1 It is a schematic architecture diagram of the communication system provided by the embodiment of the present application;

[0099] Figure 2 It is a schematic example diagram of service quality monitoring provided by the embodiment of the present application;

[0100] Figure 3 It is a schematic diagram of an embodiment of the method for delay measurement provided by the embodiment of the present application;

[0101] Figure 4 It is a schematic communication architecture diagram of delay measurement provided by the embodiment of the present application;

[0102] Figure 5A It is a schematic diagram of another embodiment of the method for delay measurement provided by the embodiment of the present application;

[0103] Figure 5B It is a schematic example diagram of the structure of a data packet provided by the embodiment of the present application;

[0104] Figure 5C It is a schematic example diagram of round-trip delay provided by the embodiment of the present application;

[0105] Figure 6A It is a schematic diagram of another embodiment of the method for delay measurement provided by the embodiment of the present application;

[0106] Figure 6BAnother schematic diagram of the round-trip delay provided by the embodiments of the present application;

[0107] Figure 7A Another schematic diagram of the method for delay measurement provided by the embodiments of the present application;

[0108] Figure 7B An exemplary schematic diagram of the uplink delay provided by the embodiments of the present application;

[0109] Figure 8A Another schematic diagram of the method for delay measurement provided by the embodiments of the present application;

[0110] Figure 8B An exemplary schematic diagram of the downlink delay provided by the embodiments of the present application;

[0111] Figure 9 A schematic diagram of the structure of the communication device provided by the embodiments of the present application;

[0112] Figure 10 Another schematic diagram of the structure of the communication device provided by the embodiments of the present application;

[0113] Figure 11 Another schematic diagram of the structure of the communication device provided by the embodiments of the present application;

[0114] Figure 12 Another schematic diagram of the structure of the communication device provided by the embodiments of the present application. Detailed implementation manners

[0115] The embodiments of the present application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Those of ordinary skill in the art will understand that with the development of technology and the emergence of new scenarios, the technical solutions provided by the embodiments of the present application are equally applicable to similar technical problems.

[0116] Terms such as "first" and "second" in the specification, claims and the above-mentioned drawings of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances, so that the embodiments described here can be implemented in an order different from that shown or described here. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0117] The present application provides a method for delay measurement, which is used to measure the air interface delay of each data packet with relatively small overhead. The present application also provides corresponding devices, systems, computer-readable storage media, computer program products, etc. The following will be described in detail respectively.

[0118] The technical solutions of the embodiments of the present application can be applied to various communication systems, such as: Long Term Evolution (LTE) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication systems, 5th Generation (5G) systems, New Generation (NR) communication systems or future 6th generation communication systems, etc.

[0119] The part operated by an operator in various communication systems can be called an operator network. The operator network can also be called a Public Land Mobile Network (PLMN) network, which is a network established and operated by a government or an operator approved by the government for the purpose of providing public land mobile communication services. It is mainly a public network in which a Mobile Network Operator (MNO) provides mobile broadband access services for users. The operator network or PLMN network described in the embodiments of the present application can be a network that meets the requirements of the 3rd Generation Partnership Project (3GPP) standard, simply referred to as a 3GPP network. Usually, the 3GPP network is operated by an operator, including but not limited to 5th-generation (5G) mobile communication networks, 4th-generation (4G) mobile communication networks or 3rd-generation (3G) mobile communication technology networks. It also includes future 6th-generation (6G) mobile communication networks.

[0120] The communication system architecture is usually divided into two parts: an access network and a core network. The access network is used to implement functions related to wireless access. The core network mainly realizes functions such as user plane management and control plane management through different network elements. The following takes Figure 1Take it as an example to introduce the communication system involved in the embodiments of the present application.

[0121] Figure 1 It is a schematic diagram of a communication system in the embodiments of the present application. As Figure 1 shown, the communication system includes an access and mobility management function (AMF), a session management function (SMF) network element, a policy control function (PCF) network element, a user plane function (UPF) network element, a network exposure function (NEF), an application function (AF), a unified data management (UDM), a terminal device (also referred to as a user equipment (UE)), a radio access network (RAN), and a data network (DN), etc.

[0122] Next, a brief introduction will be given to Figure 1 each network function (or network element) shown in

[0123] Terminal device: It can be referred to as a user equipment, an access terminal, a user unit, a user station, a mobile station, a mobile platform, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent, or a user device.

[0124] A terminal device can be a device that provides voice / data to users. For example, it can be a handheld device with wireless connection function, a vehicle-mounted device, etc. Currently, some examples of terminals are: mobile phone, tablet computer, laptop computer, palmtop computer, mobile internet device (MID), wearable device, virtual reality (VR) device, augmented reality (AR) device, wireless terminal in industrial control, wireless terminal in self-driving, wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, wireless terminal in smart home, cellular phone, cordless phone, session initiation protocol (SIP) phone, wireless local loop (WLL) station, personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing devices connected to a wireless modem, wearable device, a terminal device in a 5G network or a terminal device in a future evolved public land mobile communication network, etc. The embodiments of the present application are not limited thereto.

[0125] By way of example and not limitation, in the embodiments of the present application, the terminal device can also be a wearable device. A wearable device can also be called a wearable intelligent device, which is a general term for devices developed by applying wearable technology to the intelligent design of daily wear, such as glasses, gloves, watches, clothing, shoes, etc. A wearable device is a portable device that is either directly worn on the body or integrated into the user's clothes or accessories. A wearable device is not just a hardware device, but also realizes powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable intelligent devices include those with complete functions and large sizes that can achieve complete or partial functions without relying on a smart phone, such as smart watches or smart glasses, etc., and those that only focus on a certain type of application function and need to cooperate with other devices such as smart phones, such as various smart bracelets and smart jewelry for physical sign monitoring.

[0126] In addition, in the embodiments of the present application, the terminal device may also be a terminal device in an Internet of Things (IoT) system. The IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, so as to realize an intelligent network of human-machine interconnection and object-object interconnection.

[0127] It should be noted that the terminal device and the access network device may communicate with each other using a certain radio access technology (such as NR or LTE technology, etc.). The terminal device and the terminal device may also communicate with each other using a certain radio access technology (such as NR or LTE technology, etc.).

[0128] In the embodiments of the present application, the terminal device may be replaced by a device for implementing the functions of the terminal device, or may be a device capable of supporting the terminal device to implement such functions, such as a chip system or a chip. This device may be installed in the terminal device. In addition, the chip system may be composed of chips, or may include chips and other discrete devices.

[0129] An access network device (also known as a radio access network) can be a device with radio transceiver functions. The access network device can be a device that provides wireless communication function services and is usually located on the network side, including but not limited to: the next-generation base station (gNodeB, gNB) in the fifth-generation communication system, the next-generation base station in the sixth-generation (mobile communication system), the base station in the future mobile communication system, or the access node in the WiFi system, etc., the evolved node B (eNB) in the LTE system, the radio network controller (RNC), the node B (NB), the base station controller (BSC), the home base station (e.g., home evolved NodeB, or home Node B, HNB), the wireless access point, the base band unit (BBU), the transmission reception point (TRP), the transmitting point (TP), the base transceiver station (BTS), etc. In one network structure, the access network device can include a centralized unit (CU) node, or a distributed unit (DU) node, or a RAN device including a CU node and a DU node, or a RAN device with a control plane CU node and a user plane CU node, and a DU node. The access network device provides services for a cell, and the user equipment communicates with the base station through the transmission resources used by the cell (e.g., frequency domain resources, or in other words, spectrum resources). The cell can be the cell corresponding to the base station (e.g., the base station), and the cell can belong to a macro base station or a base station corresponding to a small cell. Here, the small cell can include: the metro cell, the micro cell, the pico cell, the femto cell, etc. These small cells have the characteristics of small coverage range and low transmission power and are suitable for providing high-rate data transmission services. The access network device can be a macro base station, a micro base station or an indoor station, and can also be a relay node or a donor node, a device that provides wireless communication services for user equipment in the V2X communication system, a wireless controller in the cloud radio access network (CRAN) scenario, a relay station, a vehicle-mounted device, a wearable device, and network devices in future evolved networks, etc. The embodiments of the present application do not limit the specific technologies and specific device forms adopted by the access network device.

[0130] The access network device is a device that provides access for terminal devices and may include RAN devices and (access network, AN) devices. RAN devices are mainly wireless network devices in 3GPP networks, and AN can be an access network device defined by non-3GPP.

[0131] RAN device: It is mainly responsible for functions such as radio resource management on the air interface side, quality of service (QoS) management, data compression, and encryption. RAN devices can include various forms of base stations, such as: macro base stations, micro base stations (also known as small stations), relay stations, access points, etc. In systems using different radio access technologies, the names of devices with base station functions may vary. For example, in the fifth generation (5th generation, 5G) system, it is called RAN or gNB (5G NodeB); in the LTE system, it is called evolved NodeB (eNB or eNodeB); in the third generation (3rd generation, 3G) system, it is called Node B, etc.

[0132] AN device: This network element allows terminal devices and the 3GPP core network to interoperate using non-3GPP technologies. Among them, non-3GPP technologies include, for example: wireless fidelity (Wi-Fi), worldwide interoperability for microwave access (WiMAX), code division multiple access (CDMA) networks, etc.

[0133] The UDM network element (which can also be called the unified data management network element, unified data management network element entity, data management device, unified data management network element device) is a type of core network device mainly used for processing terminal device identification, access authentication, registration, and mobility management, etc. Unified data management is a control plane device.

[0134] PCF network element (which can also be called the policy control network element, policy control function network element, policy control device, policy control function network element entity, etc.): It is mainly responsible for policy control functions such as charging, service quality bandwidth guarantee, and mobility management, and terminal device policy decision-making at the session and service flow levels.

[0135] SMF network element (which can also be called the session management function network element): It mainly performs functions such as session management, execution of control policies sent by PCF, selection of UPF, and allocation of Internet protocol addresses for terminal devices.

[0136] The AMF network element (which can also be referred to as an access and mobility management function entity, access and mobility management device, access and mobility management function network element, access management device, or mobility management device) is a type of core network device mainly used for mobility management and access management, etc. It can be used to implement other functions of the mobility management entity (MME) function except session management. For example, functions such as lawful interception, or access authorization (or authentication), registration of user equipment, mobility management, tracking area update process, reachability detection, selection of session management function network elements, and mobile state transition management.

[0137] The UPF network element (which can also be referred to as a user plane device, user plane function network element, user plane function entity): mainly includes the following functions: user plane-related functions such as packet routing and transmission, packet detection, service usage reporting, QoS processing, uplink packet detection, and downlink packet storage.

[0138] The AF network element is similar to an application server. It interacts with other 5G core network control planes (NFs) and provides service. AF can exist for different application services and can be owned by the operator or a trusted third party. For example, the main function of this network element is to inform the PCF of the latest business requirements of a third-party enterprise for a certain application. The PCF will generate corresponding quality of service (QoS) rules according to the requirements to ensure that the services provided by the network meet the requirements put forward by the third party.

[0139] It should be noted that the application server in the embodiments of this application includes an application function (AF) and / or an application server (application sever, AS) or other devices (or functions or network elements, etc.) that can support or provide application services (or business services). The embodiments of this application do not make specific limitations on this.

[0140] The NEF network element can also be referred to as a network open device, network open function entity, network open function network element, network capability open function entity, network capability open function device, network capability open function network element, or network capability open device, etc. NEF is mainly used to support the opening of capabilities and events, such as safely opening the services and capabilities provided by 3GPP network functions to the outside.

[0141] It should be understood that the RAN, SMF, PCF, or AF in the embodiments of this application can also be referred to as a communication device or communication equipment, which can be a general device or a dedicated device. This application does not make specific limitations on this.

[0142] It should also be understood that the above names are only used to distinguish different functions and do not mean that these devices are separate physical devices. The specific forms of the above devices are not limited in this application. For example, they can be integrated into the same physical device or can be different physical devices respectively. In actual deployment, network functions (or simply referred to as functions), network elements or devices can be co-located. For example, the access and mobility management function network element can be co-located with the session management function network element; the session management function network element can be co-located with the user plane function network element. When two functions are co-located, the interaction between the two functions provided in the embodiments of this application becomes an internal operation of the co-located function or can be omitted.

[0143] It can be understood that the above functions can be either network elements in hardware devices, software functions running on dedicated hardware, or a combination of hardware and software, or virtualized functions instantiated on a platform (such as a cloud platform).

[0144] It should be noted that Figure 1 the naming of each device (such as AF, SMF, PCF, AMF, etc.) is just a name, and the name does not limit the function of the device itself. In the 5G network and other future networks, the above devices can also have other names, which are not specifically limited in this application. For example, in the 6G network, some or all of the above network elements may use the terms in 5G, or may have other names, etc. This is uniformly explained here and will not be elaborated below.

[0145] In the embodiments of this application, the direction from the terminal device to the application server (or the user plane function network element) is called the uplink direction. Correspondingly, the direction from the application server (or the user plane function network element) to the terminal device is called the downlink direction.

[0146] Currently, when the user plane function network element receives a data packet in the downlink direction, the user plane function network element will encapsulate the data packet (packets) into the same quality of service flow (QoS flow) according to the flow processing rule (Packet Detection Rule, PDR) pre-configured by the session management function network element. The PDR of the session management function network element is obtained from the policy and charging control rule (PCC Rules) of the policy management function network element. The QoS identifier (QoS flow identifier, QFI) of each QoS flow is associated with a QoS template (QoS profile). The network side will provide the same QoS guarantee for the data packets belonging to the same QoS flow according to the QoS parameters in the QoS template. The QoS guarantee includes but is not limited to: delay, forwarding priority, or packet loss rate, etc.

[0147] The policy management function network element generates PCC rules, and then the session management function network element obtains the QoS requirements of the corresponding QoS flows based on the PCC rules. Usually, the QoS requirements can be represented by QoS parameters. In the PCC rules, the packet delay budget (PDB) can be used to define the transmission delay requirements.

[0148] The measurement of delay can be through QoS monitoring, and QoS monitoring can be achieved through flow granularity monitoring or node granularity monitoring.

[0149] Flow granularity monitoring can be that the SMF network element sends the QoS monitoring policy of the QoS flow to the UPF network element through the protocol data unit (PDU) session establishment or modification process. Then, the UPF network element initiates the packet delay measurement between the (R)AN device and the UPF network element, and the (R)AN device initiates the delay measurement of the uplink / downlink packets on the Uu interface.

[0150] When the UPF network element sends a downlink packet, if all user plane nodes of the communication system are time-synchronized, the UPF network element adds the transmission timestamp (such as Figure 2 T1 in Figure 2 ) to the downlink message. The (R)AN device calculates the downlink delay according to the reception time of the received message (such as T2 in Figure 2 ), and sends the downlink delay and the Uu interface delay to the UPF network element in the uplink message.

[0151] Figure 2 In the case of no uplink service packet, the (R)AN device can send a Dummy uplink packet to the UPF network element as a listening response packet. The UPF network element can calculate the transmission delay of each segment of the uplink and downlink messages according to the information reported by the (R)AN device, the time when the (R)AN device sends the uplink message (such as T3 in Figure 2 ), and the time when the packet is received (such as Figure 2 T4 in Figure 2 ).

[0152] If the UPF network element and the (R)AN device do not support time synchronization, the UPF network element records the local time when the downlink message is sent. The (R)AN device provides the UPF network element with the Uu interface uplink / downlink packet delay measurement results and the local packet sending and receiving times through the N3 interface. The anchor UPF network element can calculate the message round-trip time according to the local reception time of the uplink message and the information reported by the (R)AN device. If the uplink and downlink delays between the (R)AN device and the UPF network element are symmetric, the one-way delay can be obtained by dividing by 2.

[0153] The UPF network element can report the QoS monitoring results to the SMF according to certain conditions (such as reaching the SMF reporting threshold) for subsequent application layer alarms or other QoS policy decisions, etc.

[0154] Node-level QoS monitoring can provide delay estimation results at the node granularity. Different from the above QoS flow-level QoS monitoring, node-level monitoring is based on the General Packet Radio System Tunnelling Protocol for the User Plane (GTP-U) Echo request / response in the user plane transmission path to estimate the core network packet delay. Simply put, it is to use the GTP-U Echo request / response in the user plane transmission path to estimate the core network packet delay for the delay of the uplink / downlink data packets between the (R)AN device and the UPF network element in the above QoS flow level. Among them, GTP-U is used to carry user data within the GPRS core network and between the radio access network and the core network. The transmitted user data can be any type of data packet in Internet Protocol Version 4 (IPv4), Internet Protocol Version 6 (IPv6), Ethernet, or Point-to-Point Protocol (PPP).

[0155] The above Figure 1 The following shows a simplified architecture diagram of the communication system. In fact, in different scenarios, the architecture of the communication system may vary slightly. For example: non-roaming scenarios and roaming scenarios. Non-roaming scenarios can also be divided into architectures based on service-based interfaces and architectures based on reference points. Roaming scenarios can also be divided into architectures based on service-based interfaces and architectures based on reference points. Roaming scenarios can also be further divided into local breakout (LBO) roaming scenarios and home routed (HR) roaming scenarios. LBO roaming scenarios can also be divided into architectures based on service-based interfaces and architectures based on reference points; HR roaming scenarios can also be divided into architectures based on service-based interfaces and architectures based on reference points. No matter which architecture, the delay measurement method provided by the embodiments of the present application can be applied.

[0156] The following describes the delay measurement method provided by the embodiments of the present application with reference to the accompanying drawings. This process can be executed by the user plane device or by other devices in the core network (such as: SMF network element, PCF network element or AF network element). Such as Figure 3As shown in the figure, an embodiment of the method for delay measurement provided by the embodiments of the present application includes:

[0157] 301. Obtain a first delay and a second delay of a first data packet. The first delay is the delay between the user plane device and the terminal device, and the second delay is the delay between the user plane device and the access network device.

[0158] In the present application, the user plane device may be a device in the core network that can perform user plane functions, such as: a UPF network element. The access network device may be various types of base stations, and can be understood by referring to the previous introduction to the access network equipment. The terminal device may be a device with air interface transmission capabilities or a set including a device with air interface transmission capabilities and other devices.

[0159] In the present application, the first delay may be the delay measured using the user plane protocol between the terminal device and the user plane device, such as: the delay between the terminal device and the user plane device measured through the performance measurement functionality (PMF) protocol. This delay may be the round trip time (RTT), uplink delay, or downlink delay between the terminal device and the user plane device, where RTT is also referred to as round trip delay.

[0160] In the present application, the second delay may be the delay between the user plane device and the access network device measured through the QoS Monitoring process. This delay may be the RTT, uplink delay, or downlink delay between the user plane device and the access network device.

[0161] Regarding the PMF protocol, as well as the relationship between QoS monitoring and the terminal device, access network device, and user plane device, reference can be made to Figure 4 for understanding. Such as Figure 4As shown in the figure, the terminal device includes, from bottom to top, layer 1 (layer1, L1), medium access control (MAC) layer, radio link control (RLC) layer, packet data convergence protocol (PDCP) layer, and service data application protocol (SDAP) layer. The user plane device includes, from bottom to top, layer 1 (L1), layer 2 (L2), user datagram protocol / internet protocol (UDP / IP) layer, GTP-U layer. In addition, the upper layers of the terminal device and the user plane device both include the PMF protocol layer. The layer structure of the access network device facing the terminal device is the same as that of the terminal device, and the layer structure facing the user plane device is the same as that of the user plane device.

[0162] Among them, L1 can be the physical layer, and L2 layer can be the network layer.

[0163] The MAC layer is used to arbitrate network capacity.

[0164] The RLC layer is used to repair errors and perform flow control.

[0165] The PDCP layer is used to process the packet data of the network layer carried on the air interface, such as IP data streams.

[0166] The SDAP layer is used for QoS flow processing across the air interface, such as mapping a specific QoS flow in a PDU session to the corresponding data radio bearer.

[0167] The UDP / IP layer is used for data transmission.

[0168] The GTP-U layer is used to carry user data within the GPRS core network and between the radio access network and the core network.

[0169] 302. Determine the target delay according to the first delay and the second delay, where the target delay is the delay between the terminal device and the access network device.

[0170] In this application, the target delay can be the air interface delay between the terminal device and the access network device, and this target delay can be the difference between the first delay and the second delay.

[0171] In the embodiments of the present application, for each data packet, the first delay between the terminal device and the user plane device, and the second delay between the user plane device and the access network device can be obtained, and then the air interface delay between the terminal device and the access network device can be calculated through the first delay and the second delay. This method of determining the air interface delay does not require the terminal device and the access network device to specifically send multiple data packets carrying timestamps for measurement, reducing the overhead caused by measuring the air interface delay, thereby improving the air interface capacity of the access network device and the terminal device.

[0172] The above first delay, second delay, and target delay can all be RTT, uplink delay, or downlink delay. The delay measurement processes for different situations are introduced below.

[0173] 1.1, Delay measurement of RTT;

[0174] As Figure 5A shown, another embodiment of the delay measurement provided by the embodiments of the present application includes:

[0175] 501. The AF network element sends a subscription request for service quality monitoring to the PCF network element.

[0176] Optionally, the subscription request may carry the per packet QoS Monitoring type, and the per packet QoS Monitoring type indicates that service quality monitoring needs to be performed on each data packet. The per packet QoS Monitoring type may be segmented per packet QoS Monitoring. The segmented per packet QoS Monitoring may be performed on the communication link between the user plane device and the access network device. Of course, it may also be performed on the communication link between the user plane device and the terminal device, or on the communication link between the access network device and the terminal device. Of course, it may also be performed on all of these links for per packet QoS Monitoring.

[0177] 502. The PCF network element sends a PCC rule to the SMF network element, and the PCC rule includes information on per packet service quality monitoring.

[0178] The information on per packet service quality monitoring may be the per packet QoS Monitoring type.

[0179] 503. The SMF network element sends a QoS monitoring request to the UPF network element.

[0180] The QoS monitoring request includes the per packet QoS Monitoring type.

[0181] 504. The UPF network element sends a first data packet, which includes a first indication and a second indication.

[0182] The first indication is used to indicate the access network device to perform Quality of Service (QoS) monitoring. The first indication can be a QoS monitoring indication, and the second indication can be an RTT indication.

[0183] For the structure of the first data packet, reference can be made to Figure 5B for understanding. As Figure 5B shown, the header of the first data packet is the GTP-U header, which includes the QoS monitoring indication, and the payload part includes the RTT indication.

[0184] 505. The access network device reports QoS Monitoring information to the UPF network element.

[0185] This step 505 can be understood by referring to the above Figure 2 part about the method of determining the delay of QoS Monitoring.

[0186] 506. The terminal device sends an RTT response (Echo) to the UPF network element through the access network device.

[0187] Regarding the sending of the RTT response, it can be that the PMF in the terminal device sends a PMF-Echo Request message to the PMF in the UPF network element through the user, and the PMF in the UPF responds with a PMF-Echo Response message to each PMF. Similarly, it can also be that the PMF in the UPF sends a PMF-Echo Request message to the PMF in the UE through the user, and the PMF in the UE responds with a PMF-Echo Response message to each PMF. Of course, a new protocol layer can also be used to implement the same function, and this application does not limit this.

[0188] 507. The UPF network element determines the target delay.

[0189] The UPF network element can determine the RTT (the first delay) between the access network device and the UPF network element through the QoS Monitoring in step 505 above, and can determine the RTT (the second delay) between the terminal device and the UPF network element through the RTT response. Then, the target delay, that is, the air interface RTT between the terminal device and the access network device, can be obtained by taking the difference between the first delay and the second delay.

[0190] Regarding how to determine that the first delay and the second delay correspond to the delay of the same data packet, the first delay and the second delay corresponding to the same data packet can be determined by associating the first information and the second information corresponding to the first data packet. During the delay measurement process of the RTT, the first information can be the RTT response, which is used to determine the first delay, that is, the RTT between the UPF network element and the terminal device, and the second information can be the QoS monitoring information of the RTT, which is used to determine the second delay, that is, the RTT between the UPF network element and the access network device.

[0191] The association relationship between the first information and the second information of the first data packet can be maintained in various ways. For example, the association relationship between the first information and the second information of the first data packet can be maintained through the first identifier. The first identifier can be a number or index used to mark the data packet sent by the user plane device, or other identifiers, such as: sequence number (SN). For example: the first delay and the second delay corresponding to the first data packet can be determined through the application layer SN number of the PMF layer RTT Request and the corresponding GTP-U SN number. The air interface RTT (target delay) can be obtained by subtracting the delay (the second delay) of the QoS Monitoring of the corresponding GTP-U SN number from the E2E delay (the first delay) corresponding to the application layer SN number of the PMF layer RTT Request. Optionally, in the delay association of the RTT echo and the QoS Monitoring, it can be associated through the original SN or the new SN. When using the new SN number to associate the above first information and second information, the first information and the second information can also carry the corresponding relationship between the new SN and the original SN. The UPF network element can use the corresponding relationship between the new SN and the original SN to determine the first delay and the second delay corresponding to the same data packet, and then determine the corresponding air interface delay.

[0192] Regarding the process of determining the air interface RTT, reference can be made to Figure 5C for understanding. As Figure 5C shown, the delay 511 represents the RTT between the user plane device and the terminal device, and the delay 512 represents the RTT between the user plane device and the access network device. Then, the air interface RTT, that is, the RTT between the access network device and the terminal device, can be obtained by subtracting the delay 512 from the delay 511.

[0193] In the solution provided by the embodiment of the present application, the user plane device can complete two measurements through one data packet, that is, it can measure the first delay and the second delay. Among them, the first delay and the second delay are associated through the first identifier, and the UPF network element can accurately calculate the corresponding air interface delay of the data packet. In this way, both the measurement overhead of the air interface delay is reduced, and the accuracy of the air interface delay measurement can be improved.

[0194] 1.2, RTT delay measurement;

[0195] As Figure 6A shown, another embodiment of the delay measurement provided by the embodiment of the present application includes:

[0196] Steps 601 to 604 in the embodiment of the present application are the same as steps 501 to 504, and can be understood by referring to the previous introduction.

[0197] 605. The terminal device sends an RTT Echo to the access network device, and the RTT Echo includes a third indication.

[0198] The third indication is used to instruct the access network device to add the second information to the message where the first information is located.

[0199] 606. The access network device adds the second information to the RTT Echo according to the third indication.

[0200] The second information may be RTT QoS monitoring information, which is used to determine the RTT between the access network device and the UPF network element.

[0201] 607. The access network device sends an RTT Echo containing the first information and the second information to the access network device.

[0202] By sending the first information and the second information in the same message, after receiving the message, the user plane device can directly calculate the first delay and the second delay, and then obtain the air interface delay, without the need to search for the association relationship, further improving the calculation speed of the air interface delay.

[0203] 608. The UPF network element determines the target delay according to the RTT Echo.

[0204] This step 608 can be understood by referring to step 507 above. The air interface delay of the RTT can be understood by referring to the above Figure 6B For understanding, delay 611 represents the RTT between the user plane device and the terminal device, and delay 612 represents the RTT between the user plane device and the access network device. Then, by subtracting delay 612 from delay 611, the RTT of the air interface can be obtained, that is, the RTT between the access network device and the terminal device.

[0205] The above provided by the embodiments of the present application Figure 5A and Figure 6A The embodiments can utilize the end-to-end per-packet delay monitoring between the terminal device and the UPF network element and the per-packet delay monitoring between the access network device and the UPF network element to obtain the RTT delay of the air interface, reducing the overhead brought by measuring the air interface delay, thereby improving the air interface capacity of the terminal device and the access network device.

[0206] 2. Measurement of uplink delay;

[0207] As Figure 7A shown, another embodiment of the delay measurement provided by the embodiments of the present application includes:

[0208] Steps 701 to 703 in the embodiments of the present application are the same as steps 501 to 503, and can be understood by referring to the previous introduction.

[0209] 704. The UPF network element sends a first data packet, and the first data packet includes a first indication and a second indication.

[0210] Different from the above step 504, the second indication is used to indicate the sending of an uplink synchronization message.

[0211] 705. The terminal device / DS-TT sends an uplink synchronization message, and the uplink synchronization message includes a third indication.

[0212] The third indication is used to indicate that the access network device adds the second information to the uplink synchronization message.

[0213] When the terminal device is associated with a device-side time sensitive network translator (DS-TT), and the DS-TT is connected to the terminal device, the uplink synchronization message can be sent by the DS-TT, and the uplink synchronization message is sent to the access network device through the air interface of the terminal device.

[0214] 706. The access network device adds the second information to the uplink synchronization message according to the third indication.

[0215] During the uplink delay measurement process, the second information is uplink QoS monitoring information, which is used to determine the uplink delay between the access network device and the UPF network element.

[0216] 707. The access network device sends an uplink synchronization message containing the first information and the second information to the UPF network element.

[0217] During the uplink delay measurement process, the first piece of information can be the timestamp when the terminal device sends an uplink synchronization message, which is used to determine the first delay by the UPF network element when receiving the uplink synchronization message, that is, the uplink delay between the terminal device and the UPF network element.

[0218] 708. The UPF network element determines the target delay based on the uplink synchronization message.

[0219] For the process of determining the uplink delay of the air interface, reference can be made to Figure 7B for understanding. As Figure 7B shown, taking the terminal device associated with DS-TT and the terminal device as an example, delay 711 represents the uplink delay between DS-TT and the user plane device, delay 712 represents the uplink delay between the access network device and the user plane device, and delay 713 represents the delay of the air interface from DS-TT to the terminal device. As Figure 7B known, the uplink delay of the air interface = delay 711 - delay 712 - delay 713.

[0220] Of course, if the terminal device is not associated with DS-TT, but directly sends an uplink synchronization message through the air interface similar to Figure 5C then there will be no delay 713. At this time, the uplink delay of the air interface = delay 711 - delay 712.

[0221] In the embodiments of the present application, through the processes introduced above Figure 7A and Figure 7B it can be seen that the uplink delay of the air interface is obtained by using the end-to-end per-packet delay monitoring between the terminal device and the UPF network element and the per-packet delay monitoring between the access network device and the UPF network element, reducing the overhead caused by measuring the uplink delay of the air interface, thereby improving the air interface capacity of the terminal device and the access network device.

[0222] 3. Measurement of downlink delay;

[0223] As Figure 8A shown, another embodiment of the delay measurement provided by the embodiments of the present application includes:

[0224] In the embodiments of the present application, steps 801 to 803 are the same as steps 501 to 503, and reference can be made to the previous introduction for understanding.

[0225] 804. The UPF network element sends a first data packet, and the first data packet includes a first indication and a second indication.

[0226] Different from step 504 above, the second indication in the first data packet is used to indicate the sending of a downlink synchronization message, and the downlink synchronization message further includes a downlink delay indication, and the downlink delay indication is used to indicate that the terminal device reports the downlink delay between the user plane device and the terminal device.

[0227] 805. The terminal device / DS-TT sends the downlink latency to the UPF network element through the access network device.

[0228] During the measurement of the downlink latency, Figure 3 The first information in the described embodiments may be the downlink latency.

[0229] 806. The access network device reports QoS Monitoring information to the UPF network element.

[0230] This step 805 can be understood by referring to the above Figure 2 part about the method of determining the latency by QoS Monitoring. This QoS Monitoring information is Figure 3 the second information in the described embodiments. During the downlink latency measurement, this second information is the downlink Qos monitoring information, which is used to determine the downlink latency between the UPF network element and the access network device.

[0231] 807. The UPF network element determines the target latency.

[0232] Regarding the process of determining the downlink latency of the air interface, it can be referred to Figure 8B for understanding. As Figure 8B shown, taking the terminal device associated with DS-TT as an example, latency 811 represents the downlink latency between DS-TT and the user plane device, latency 812 represents the downlink latency between the access network device and the user plane device, and latency 813 represents the latency of the air interface from DS-TT to the terminal device. From Figure 8B it can be known that the downlink latency of the air interface = latency 811 - latency 812 - latency 813.

[0233] Of course, if the terminal device is not associated with DS-TT, but directly receives the downlink synchronization packet through the air interface similar to Figure 5C then there will be no latency 813. At this time, the downlink latency of the air interface = latency 811 - latency 812.

[0234] In the embodiments of the present application, through the above Figure 8A and Figure 8B described processes, it can be seen that the downlink latency of the air interface is obtained by using the end-to-end per-packet latency monitoring between the terminal device and the UPF network element and the per-packet latency monitoring between the access network device and the UPF network element, reducing the overhead brought by measuring the downlink latency of the air interface, thereby improving the air interface capacity of the terminal device and the access network device.

[0235] In the above-introduced several embodiments, the second indication indicates different contents in different forms, so that the terminal device returns the corresponding RTT response information, uplink synchronization packet or downlink latency, thereby completing the measurement of RTT, uplink latency or downlink latency.

[0236] In an embodiment of the present application, the third delay between the user plane device and the application server may also be obtained; based on the first delay and the third delay, the delay between the terminal device and the application server is determined.

[0237] It should be noted that the above process of determining the target delay is described by taking the UPF network element as an example. In fact, this process may be executed by other devices in the core network. If it is executed by other devices, only the first delay and the second delay need to be obtained from the user plane device.

[0238] The communication system and the method for measuring delay in the embodiments of the present application are introduced above. Next, the communication device in the embodiments of the present application is introduced.

[0239] Please refer to Figure 9 , which is a schematic diagram of an implementation of the communication device provided by the present application. The communication device 900 includes a processing module 901 and a transceiver module 902. The communication device 900 can implement the functions of the communication device (including the user plane device, the access network device, or the terminal device) in the above method embodiments, and thus can also achieve the beneficial effects possessed by the above method embodiments. In an embodiment of the present application, the communication device 900 may be a user plane device, an access network device, or a terminal device, or may also be an integrated circuit or component inside the user plane device, the access network device, or the terminal device, such as a chip, or may be an integrated circuit or component integrating the user plane device, the access network device, or the terminal device inside.

[0240] Please refer to Figure 10 , which is another schematic structural diagram of the communication device 1000 provided by the present application. The communication device 1000 includes at least an input / output interface 1002. Among them, the communication device 1000 may be a chip or an integrated circuit.

[0241] Optionally, the communication device further includes a logic circuit 1001.

[0242] Among them, Figure 9 the shown transceiver module 902 may be a communication interface, and this communication interface may be Figure 10 the input / output interface 1002 in , and the input / output interface 1002 may include an input interface and an output interface. Alternatively, this communication interface may also be a transceiver circuit, and this transceiver circuit may include an input interface circuit and an output interface circuit.

[0243] Optionally, when the communication device 1000 is the user plane device, the access network device, or the terminal device in the foregoing embodiments, the input / output interface 1002 is used for inputting and outputting information; the logic circuit 1001 is used to execute the method executed by the user plane device, the access network device, or the terminal device in the foregoing embodiments.

[0244] Among them, the logic circuit 1001 and the input / output interface 1002 can also execute other steps performed by the communication device in any embodiment and achieve the corresponding beneficial effects, which will not be elaborated here.

[0245] In a possible implementation, Figure 9 the processing module 901 shown can be Figure 10 the logic circuit 1001 in

[0246] Optionally, the logic circuit 1001 can be a processing device, and the functions of the processing device can be implemented partially or entirely by software. Among them, the functions of the processing device can be implemented partially or entirely by software.

[0247] Optionally, the processing device can include a memory and a processor. Among them, the memory is used to store a computer program, and the processor reads and executes the computer program stored in the memory to perform the corresponding processing and / or steps in any method embodiment.

[0248] Optionally, the processing device can only include a processor. The memory for storing the computer program is located outside the processing device, and the processor is connected to the memory through a circuit / wire to read and execute the computer program stored in the memory. Among them, the memory and the processor can be integrated together or physically independent of each other.

[0249] Optionally, the processing device can be one or more chips or one or more integrated circuits. For example, the processing device can be one or more field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), system-on-chip (SoCs), central processing units (CPUs), network processors (NPs), digital signal processing circuits (DSPs), microcontroller units (MCUs), programmable logic devices (PLDs), or other integrated chips, or any combination of the above chips or processors, etc.

[0250] Please refer to Figure 11, the communication device 1100 involved in the above embodiments provided for the embodiments of the present application. The communication device 1100 may specifically be the communication device acting as a user plane device, an access network device, or a terminal device in the above embodiments.

[0251] Among them, a possible schematic diagram of the logical structure of the communication device 1100. The communication device 1100 may include but is not limited to at least one processor 1101 and a communication port 1102.

[0252] Further optionally, the device may further include at least one of a memory 1103 and a bus 1104. In the embodiments of the present application, the at least one processor 1101 is used to control and process the actions of the communication device 1100.

[0253] In addition, the processor 1101 may be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute various exemplary logical blocks, modules, and circuits described in conjunction with the disclosure of the present application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processor and a microprocessor, and so on. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0254] It should be noted that Figure 11 The shown communication device 1100 may specifically be used to implement the steps implemented by the user plane device, the access network device, or the terminal device in the foregoing method embodiments, and achieve the corresponding technical effects of the user plane device, the access network device, or the terminal device. Figure 11 For the specific implementation manners of the shown communication device, reference may be made to the descriptions in the foregoing method embodiments, and details will not be repeated here one by one.

[0255] Please refer to Figure 12 , a schematic diagram of the structure of the communication device 1200 involved in the above embodiments provided for the embodiments of the present application. The communication device 1200 may specifically be the communication device acting as a user plane device, an access network device, or a terminal device in the above embodiments. Among them, the structure of the communication device may refer to Figure 12 the structure shown.

[0256] The communication device 1200 includes at least one processor 1201 and at least one network interface 1204. Further optionally, the communication device further includes at least one memory 1202, at least one transceiver 1203, and one or more antennas 1205. The processor 1201, the memory 1202, the transceiver 1203, and the network interface 1204 are connected, for example, connected by a bus. In the embodiments of the present application, this connection may include various interfaces, transmission lines, or buses, etc., and this embodiment does not limit this. The antenna 1205 is connected to the transceiver 1203. The network interface 1204 is used to enable the communication device to communicate with other communication devices through a communication link. For example, the network interface 1204 may include a network interface between the communication device and a core network device, such as an S1 interface. The network interface may include a network interface between the communication device and other communication devices (such as other radio access networks or core network devices), such as an X2 or Xn interface.

[0257] The processor 1201 is mainly used to process communication protocols and communication data, and to control the entire communication device, execute software programs, and process data of software programs, for example, to support the communication device to perform the actions described in the embodiments. The communication device may include a baseband processor and a central processor. The baseband processor is mainly used to process communication protocols and communication data, and the central processor is mainly used to control the entire communication device, execute software programs, and process data of software programs. Figure 12 The processor 1201 in [description] may integrate the functions of the baseband processor and the central processor. Those skilled in the art can understand that the baseband processor and the central processor may also be separate processors, interconnected through technologies such as a bus. Those skilled in the art can understand that the terminal device may include multiple baseband processors to adapt to different network modes, the terminal device may include multiple central processors to enhance its processing ability, and various components of the terminal device may be connected through various buses. The baseband processor may also be expressed as a baseband processing circuit or a baseband processing chip. The central processor may also be expressed as a central processing circuit or a central processing chip. The function of processing communication protocols and communication data may be built into the processor or stored in the memory in the form of a software program, and the processor executes the software program to implement the baseband processing function.

[0258] The memory is mainly used to store software programs and data. The memory 1202 may exist independently and be connected to the processor 1201. Optionally, the memory 1202 may be integrated with the processor 1201, for example, integrated within a single chip. Among them, the memory 1202 can store program codes for implementing the technical solutions of the embodiments of the present application, and be controlled by the processor 1201 to execute. Various computer program codes that are executed can also be regarded as driver programs of the processor 1201.

[0259] Figure 12 Only one memory and one processor are shown. In an actual terminal device / access network device, there may be multiple processors and multiple memories. The memory may also be referred to as a storage medium or a storage device, etc. The memory may be a storage element on the same chip as the processor, that is, an on-chip storage element, or an independent storage element, and the embodiments of the present application do not limit this.

[0260] The transceiver 1203 can be used to support the reception or transmission of radio frequency signals between the communication device and the terminal. The transceiver 1203 can be connected to the antenna 1205. The transceiver 1203 includes a transmitter Tx and a receiver Rx. Specifically, one or more antennas 1205 can receive radio frequency signals. The receiver Rx of the transceiver 1203 is used to receive the radio frequency signals from the antenna, convert the radio frequency signals into digital baseband signals or digital intermediate frequency signals, and provide the digital baseband signals or digital intermediate frequency signals to the processor 1201 so that the processor 1201 can further process the digital baseband signals or digital intermediate frequency signals, such as demodulation processing and decoding processing. In addition, the transmitter Tx in the transceiver 1203 is also used to receive the modulated digital baseband signals or digital intermediate frequency signals from the processor 1201, convert the modulated digital baseband signals or digital intermediate frequency signals into radio frequency signals, and transmit the radio frequency signals through one or more antennas 1205. Specifically, the receiver Rx can selectively perform one or more levels of down-conversion processing and analog-to-digital conversion processing on the radio frequency signals to obtain digital baseband signals or digital intermediate frequency signals, and the order of the down-conversion processing and the analog-to-digital conversion processing can be adjusted. The transmitter Tx can selectively perform one or more levels of up-conversion processing and digital-to-analog conversion processing on the modulated digital baseband signals or digital intermediate frequency signals to obtain radio frequency signals, and the order of the up-conversion processing and the digital-to-analog conversion processing can be adjusted. The digital baseband signals and the digital intermediate frequency signals can be collectively referred to as digital signals.

[0261] The transceiver 1203 can also be referred to as a transceiver module, a transceiver, a transceiver device, etc. Optionally, the devices used to implement the reception function in the transceiver module can be regarded as a receiving unit, and the devices used to implement the transmission function in the transceiver module can be regarded as a transmitting unit. That is, the transceiver module includes a receiving unit and a transmitting unit. The receiving unit can also be referred to as a receiver, an input port, a receiving circuit, etc., and the transmitting unit can be referred to as a transmitter, a transmitter, or a transmitting circuit, etc.

[0262] It should be noted that Figure 12 The shown communication device 1200 can specifically be used to implement the steps implemented by the user plane device, the access network device, or the terminal device in the foregoing method embodiments, and achieve the corresponding technical effects of the user plane device, the access network device, or the terminal device. Figure 12For the specific implementation manners of the communication device 1200 shown, reference may be made to the descriptions in the foregoing method embodiments, and details are not described herein again.

[0263] The embodiments of the present application further provide a computer-readable storage medium storing one or more computer-executable instructions. When the computer-executable instructions are executed by a processor, the processor executes the methods of the possible implementation manners of the user plane device, the access network device, or the terminal device in the foregoing embodiments.

[0264] The embodiments of the present application further provide a computer program product (or computer program) storing one or more computers. When the computer program product is executed by the processor, the processor executes the methods of the possible implementation manners of the above user plane device, access network device, or terminal device.

[0265] The embodiments of the present application further provide a chip system. The chip system includes at least one processor, which is used to support the communication device to implement the functions involved in the possible implementation manners of the above communication device. Optionally, the chip system further includes an interface circuit, and the interface circuit provides program instructions and / or data for the at least one processor. In a possible design, the chip system may further include a memory, and the memory is used to store the necessary program instructions and data of the communication device. The chip system may be composed of chips or may include chips and other discrete devices, where the communication device may specifically be the user plane device, the access network device, or the terminal device in the foregoing method embodiments.

[0266] The embodiments of the present application further provide a communication system, which includes the user plane device, the access network device, and the terminal device in any of the foregoing embodiments.

[0267] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other may be through some interfaces, and the indirect couplings or communication connections of devices or units may be in electrical, mechanical, or other forms.

[0268] The unit described as a separated component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0269] In addition, each functional unit in various embodiments of the present application may be integrated into a processing module, may exist separately physically for each unit, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit. If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that makes a contribution, or all or part of the technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a radio access network, etc.) to execute all or part of the steps of the method in various embodiments of the present application. The foregoing storage medium includes: various media such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk, or an optical disc that can store program codes.

Claims

1. A method for measuring time delay, characterized in that, it includes: Obtain a first time delay and a second time delay of a first data packet, where the first time delay is the time delay between a user plane device and a terminal device, and the second time delay is the time delay between the user plane device and an access network device; Determine a target time delay according to the first time delay and the second time delay, where the target time delay is the time delay between the terminal device and the access network device.

2. The method according to claim 1, characterized in that, the first time delay is the round-trip time delay between the user plane device and the terminal device; the second time delay is the round-trip time delay between the user plane device and the access network device; the target time delay is the round-trip time delay between the terminal device and the access network device.

3. The method according to claim 1, characterized in that, the first time delay is the uplink time delay between the terminal device and the user plane device; the second time delay is the uplink time delay between the access network device and the user plane device; the target time delay is the uplink time delay between the terminal device and the access network device.

4. The method according to claim 1, characterized in that, the first time delay is the downlink time delay between the user plane device and the terminal device; the second time delay is the downlink time delay between the user plane device and the access network device; the target time delay is the downlink time delay between the terminal device and the access network device.

5. The method according to any one of claims 1-4, characterized in that, the obtaining of the first time delay and the second time delay of the first data packet includes: The user plane device sends the first data packet, and the first data packet contains a first indication and a second indication. The first indication is used to instruct the access network device to perform quality of service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information, where the first information is related to the first time delay; The user plane device receives the first information and second information, where the second information is the QoS monitoring information of the access network device. Among them, the first information is used to determine the first time delay, and the second information is used to determine the second time delay.

6. The method according to claim 5, characterized in that, the first information and the second information of the first data packet have an association relationship.

7. The method according to claim 6, characterized in that, the first information and the second information are associated through a first identifier.

8. The method according to claim 6 or 7, characterized in that, the first information and the second information are included in the same message.

9. The method according to claim 4 or 5, characterized in that, When the terminal device is associated with a user-side delay-sensitive network conversion device (DS-TT), the DS-TT connects to the terminal device, the first time delay is the time delay between the DS-TT and the user plane device, and the target time delay is the time delay between the terminal device and the access network device.

10. The method according to any one of claims 1-9, characterized in that, the method further includes: Obtain a third latency between the user plane device and the application server; Determine the latency between the terminal device and the application server according to the first latency and the third latency.

11. The method according to claim 2, characterized in that, the method further includes: The user plane device receives a per-packet QoS monitoring indication from the control plane device, and the per-packet QoS monitoring indication is used to instruct the user plane device to perform QoS monitoring on each transmitted data packet.

12. A latency measurement method, characterized in that, including: The access network device receives a first data packet, and the first data packet contains a first indication and a second indication. The first indication is used to instruct the access network device to perform Quality of Service (QoS) monitoring, and the second indication is used to instruct the terminal device to report first information; The access network device performs QoS monitoring between the access network device and the user plane device according to the first indication; The access network device sends the first data packet to the terminal device and receives the first information from the terminal device; The access network device sends the first information and the second information to the user plane device, where the second information is the QoS monitoring information of the access network device. Among them, the first information is used to determine a first latency, the second information is used to determine a second latency, the first latency is the latency between the user plane device and the terminal device, the second latency is the latency between the user plane device and the access network device, and the first latency and the second latency are used to determine a target latency, and the target latency is the latency between the terminal device and the access network device.

13. The method according to claim 12, characterized in that, A third indication is included in the message where the first information is located, and the third indication is used to instruct the access network device to add the second information to the message where the first information is located; The access network device adds the second information to the message where the first information is located according to the third indication.

14. A latency measurement method, characterized in that, including: The terminal device receives a first data packet, and the first data packet contains a second indication, and the second indication is used to instruct the terminal device to report first information; The terminal device determines the first information according to the second indication; The terminal device sends the first information to the access network device, and the first information is used to determine a first latency, and the first latency is the latency between the user plane device and the terminal device.

15. The method according to claim 14, characterized in that, the method further includes: The terminal device adds a third indication to the message where the first information is located, and the third indication is used to instruct the access network device to add the second information to the message where the first information is located; The terminal device sending the first information to the access network device includes: The terminal device sends a message containing the first information and the third indication to the access network device.

16. The method according to claim 14 or 15, characterized in that, The second indication in the first data packet is a message of round-trip time (RTT); correspondingly, the first information is a response message of round-trip time (RTT).

17. The method according to claim 14 or 15, wherein, the second indication in the first data packet is used to indicate the transmission of an uplink synchronization message; correspondingly, the message containing the first information is an uplink synchronization message.

18. The method according to claim 14 or 15, wherein, the second indication in the first data packet is used to indicate the transmission of a downlink synchronization message, and the downlink synchronization message further includes a downlink delay indication, and the downlink delay indication is used to indicate that the terminal device reports the downlink delay between the user plane device and the terminal device; correspondingly, the first information is the downlink synchronization delay, and the first delay is the downlink delay between the user plane device and the terminal device.

19. A communication device, wherein, the communication device includes: a transceiver module and a processing module; the transceiver module is used to perform the transceiver operations of the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18, and the processing module is used to perform the processing operations of the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18.

20. A communication device, wherein, the communication device includes: a memory for storing computer instructions; a processor for executing the computer program or computer instructions stored in the memory, so that the communication device executes the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18.

21. A communication device, wherein, the communication device includes a processor, and the processor is used to execute the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18.

22. A computer-readable storage medium, wherein, a computer program is stored thereon, and when the computer program is executed by a communication device, the communication device is caused to execute the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18.

23. A computer program product including instructions, wherein, when it runs on a computer, the computer is caused to execute the method according to any one of claims 1 to 11, 12 to 13, and 14 to 18.

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