Clock synchronization methods and clock synchronization devices

Abstract

This application provides a clock synchronization method and apparatus. The method includes: a clock synchronization function network element recalculating a new timing error for determining the timing method of an access network device based on timing data when the clock synchronization state of a communication system node becomes abnormal. Furthermore, the clock synchronization function network element compares the recalculated timing error with the timing data of the access network device to assist the access network device in re-determining the timing method. Through the embodiments of this application, it is possible to determine whether the timing requirements for terminal devices can still be met even when an anomaly occurs in the communication system, thereby improving the accuracy and stability of clock synchronization.

Description

Technical Field

[0001] This application relates to the field of communications, and more specifically, to clock synchronization methods and clock synchronization devices. Background Technology

[0002] In fields such as communications and industrial control, all tasks are based on a clock reference; therefore, accurate clock synchronization is a fundamental standard. TSN (Time Sequencing) is a mature, widely used industrial standard defined by the Institute of Electrical and Electronics Engineers (IEEE). TSN solves the problems of clock synchronization and latency calculation in networks, ensuring high consistency in task scheduling across the entire network. Many vertical industry users hope that their wired access in TSN networks can be replaced by 5G networks. Therefore, when users access TSN networks through 5G systems, they can both utilize the existing control functions of TSN networks and meet various performance indicators for TSN network data transmission through 5G systems.

[0003] For a combined 5G and TSN system, the TSN clock source sends Generalized Precision Time Protocol (gPTP) messages to various gPTP nodes within the TSN system. The 5G system can also be considered a gPTP node within the TSN system. This means that accurate TSN clock information requires precise clock synchronization between the 5G system and the TSN system. However, when clock synchronization malfunctions in nodes such as the radio access network (RAN) or user plane function (UPF) elements within the 5G system, there is currently no solution to determine whether the 5G system can still meet the time synchronization requirements for terminal devices. Summary of the Invention

[0004] This application provides a clock synchronization method and apparatus that can determine whether the occurrence of an anomaly in the communication system can still meet the requirements for timing the terminal device, thereby improving the accuracy and stability of clock synchronization.

[0005] Firstly, a clock synchronization method is provided. This method can be executed by a clock synchronization function network element, by a component of the synchronization function network element (e.g., a processor, chip, or chip system), or by a logic module or software capable of implementing all or part of the synchronization function network element's functions. The method includes: the clock synchronization function network element receiving first information from a first device, the first information indicating a change in the clock synchronization quality of the first access network device; the clock synchronization function network element determining a first error of the first access network device based on the first information, and determining whether the first error satisfies the total timing error configured by the network for a first service, the total timing error being used by the first access network device to provide timing for a first terminal device; the first error being the error generated when the clock quality of the first access network device changes.

[0006] Specifically, the aforementioned first information can be clock status notification information. The aforementioned first information can also be information about an abnormal clock synchronization status. An abnormal clock status can also be a change in the clock status, such as a clock status degradation, promotion, or failure.

[0007] Specifically, the aforementioned clock synchronization function network element can be a time-sensitive communication and time synchronization function (TSCTSF) network element, or other network elements; this application does not limit it.

[0008] Specifically, the total timing error mentioned above can be carried in the first service request, and the type of the first service is not limited in this application.

[0009] By using the above methods, it is possible to determine whether the occurrence of anomalies in the communication system can still meet the requirements for timing of terminal devices, thereby improving the accuracy and stability of clock synchronization.

[0010] In conjunction with the first aspect, in certain implementations of the first aspect, when the first error does not meet the total timing error configured by the network for the first service, the method further includes: the clock synchronization function network element determining a second error of the first access network device based on the first information, the second error being used by the first access network device to provide timing for the first terminal device. The clock synchronization function network element then sends the second error to the first access network device.

[0011] Specifically, the first error does not satisfy the total timing error configured by the network for the first service, which can be greater than or equal to the total timing error configured by the network for the first service.

[0012] Specifically, at least one timing method supported by the first access network device will produce different timing errors. A suitable timing method can be selected for timing based on the range of the second error, thereby achieving clock synchronization of the first terminal device.

[0013] In conjunction with the first aspect, in some implementations of the first aspect, the aforementioned first information may also include the identifier of the aforementioned first access network device, and / or clock quality information.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, the first device mentioned above includes the first access network device, the mobility management network element (AMF), or the operation and maintenance management (OAM) device.

[0015] In other words, if a clock synchronization function network element can obtain the first information from an access network device whose clock state is abnormal, then the clock synchronization function network element can also subscribe in advance to the first information of an access network device whose clock state is abnormal from the OAM.

[0016] The above methods can ensure that the clock synchronization function network element obtains abnormal clock synchronization status data in a timely manner and flexibly adjusts the error used by the RAN for time synchronization.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, if the first information further includes a third error, the clock synchronization function network element sending the second error to the first access network device further includes: the clock synchronization function network element sending the second error when it determines that the third error is less than or equal to the second error, wherein the third error is an error generated by the timing capability of the first access network device.

[0018] Specifically, the error generated by the timing capability of the first access network device (i.e., the third error mentioned above) may be the minimum value among the errors generated by at least one timing method supported by the first access network device, or it may be any error among the errors generated by at least one timing method supported by the first access network device. This application does not limit this.

[0019] Using the above method, the clock synchronization function network element compares the error of the first access network device (i.e., the second error mentioned above) that is re-determined when the clock synchronization status of the first access network device is abnormal with the error of the timing capability of the first access network device. After meeting the requirements, the re-determined second error is sent to the first access network device, which can improve the success rate of the first access network device re-determining the timing method.

[0020] In conjunction with the first aspect, in some implementations of the first aspect, if the aforementioned first information further includes a fourth error, the method further includes: the clock synchronization function network element determining that the fourth error is less than or equal to the aforementioned second error, wherein the fourth error is an error generated by the current timing method of the aforementioned first access network device. The clock synchronization function network element sends a timing indication to the aforementioned first access network device, the timing indication being used to instruct the aforementioned first access network device to continue timing for the aforementioned first terminal device.

[0021] Using the above method, the first access network device can continue to provide time synchronization for the first terminal device even if the clock synchronization quality of the first access network device changes but the time synchronization requirements are still met.

[0022] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes: the clock synchronization function network element receiving second information, which indicates that the first access network device cannot provide time synchronization for the first terminal device. The second information is sent by the first access network device when it determines that at least one time synchronization method supported by the first access network device cannot meet the time synchronization requirements of the second error. In another implementation, if the clock synchronization function network element determines that the fourth error is less than or equal to the second error, the clock synchronization function network element may also send a time synchronization indication to the first access network device, which instructs the first access network device to continue providing time synchronization for the first terminal device.

[0023] In another implementation, if the clock synchronization function network element determines, based on the first information, that the first access network device cannot provide clock synchronization service to the first terminal device due to an abnormal clock state, then the clock synchronization function network element can directly send a clock synchronization abnormality notification or clock degradation notification of the first access network device to the application function network element.

[0024] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes: the clock synchronization function network element determining at least one second access network device, the at least one second access network device providing time synchronization for at least one second terminal device, and the at least one second terminal device and the aforementioned first terminal device belonging to the same General Precision Clock Protocol (gPTP) instance. The clock synchronization function network element sends the aforementioned second error to at least one of the aforementioned second access network devices.

[0025] In conjunction with the first aspect, in some implementations of the first aspect, before the clock synchronization function network element sends the second error to at least one second access network device, the method further includes: the clock synchronization function network element obtaining timing data of the at least one second access network device from the access and mobility management function (AMF) network element or the operation and maintenance management (OAM) device.

[0026] Specifically, the timing data may include errors generated by the timing capability of the at least one second access network device, and / or errors generated by the current timing method of the at least one second access network device.

[0027] The method for determining the error generated by the clock synchronization function network element in comparison with the timing capability of at least one second access network device and the second error can refer to the description of the first access network device; and the method for determining the error generated by the clock synchronization function network element in comparison with the current timing method of at least one second access network device and the second error can refer to the description of the first access network device, and will not be repeated here.

[0028] In conjunction with the first aspect, in some implementations of the first aspect, the above method further includes: the clock synchronization function network element receiving third information from the second device, the third information being used to indicate at least one of the second access network devices, the second device including a mobility management network element or the operation and maintenance management (OAM) device.

[0029] Secondly, a clock synchronization method is provided. This method can be executed by a clock synchronization function network element, by a component of the synchronization function network element (e.g., a processor, chip, or chip system), or by a logic module or software capable of implementing all or part of the synchronization function network element's functions. The method includes: the clock synchronization function network element receiving fourth information from a third device, the fourth information indicating a change in the clock synchronization quality of a first user plane function network element. The clock synchronization function network element determines a fifth error of at least one second access network device based on the fourth information, and determines whether the fifth error satisfies at least one total timing error configured by the network for at least one first service, wherein at least one first service corresponds one-to-one with at least one of the aforementioned total timing errors, and the fifth error is the error generated when the clock quality of the first user plane function network element changes.

[0030] Specifically, the fourth piece of information mentioned above can be clock status notification information. It can also be information about an abnormal clock synchronization status, which could be a change in clock status, such as a clock status degradation, upgrade, or failure.

[0031] Specifically, the total timing error mentioned above can be carried in the first service request, and the type of the first service is not limited in this application.

[0032] Specifically, the aforementioned clock synchronization function network element can be a time-sensitive communication and time synchronization function (TSCTSF) network element, or other network elements; this application does not limit it.

[0033] By using the above methods, it is possible to determine whether the occurrence of anomalies in the communication system can still meet the requirements for timing of terminal devices, thereby improving the accuracy and stability of clock synchronization.

[0034] In conjunction with the second aspect, in certain implementations of the second aspect, when the fifth error does not meet the total timing error configured by the network for the first service, the method further includes: the clock synchronization function network element determining a second error for at least one of the second access network devices based on the fourth information. This second error is used by the at least one second access network device to provide timing for at least one second terminal device, where at least one second terminal device belongs to the same General Precision Clock Protocol (gPTP) instance. The clock synchronization function network element sends the second error to the second access network device.

[0035] Specifically, the fifth error mentioned above does not satisfy the total timing error configured by the network for the first service mentioned above, which can be greater than or equal to the total timing error configured by the network for the first service mentioned above.

[0036] Specifically, at least one timing method supported by the second access network device will produce different timing errors. A suitable timing method can be selected for timing based on the range of the second error, thereby achieving clock synchronization of the first terminal device.

[0037] In conjunction with the second aspect, in some implementations of the second aspect, the fourth information mentioned above also includes the identifier of the first user plane functional network element and / or clock quality information.

[0038] In conjunction with the second aspect, in some implementations of the second aspect, the third device mentioned above includes the first user plane function network element or operation, maintenance and management (OAM) device mentioned above.

[0039] In other words, if the clock synchronization function network element can obtain the fourth information from the user plane function network element whose clock state is abnormal, then the clock synchronization function network element can also subscribe in advance to the fourth information of the user plane function network element whose clock state is abnormal from the OAM.

[0040] The above methods can ensure that the clock synchronization function network element obtains abnormal clock synchronization status data in a timely manner and flexibly adjusts the error used by the RAN for time synchronization.

[0041] In conjunction with the second aspect, in some implementations of the second aspect, if the third information includes at least one sixth error, the clock synchronization function network element sending the second error to the second access network device further includes: the clock synchronization function network element sending the second error when it determines that the sixth error is less than or equal to the second error, wherein the at least one sixth error is an error generated by the timing capability of the at least one second access network device.

[0042] Specifically, the error generated by the timing capability of the second access network device can be the minimum value among the errors generated by at least one timing method supported by the second access network device, or it can be any error among the errors generated by at least one timing method supported by the second access network device. This application does not limit this.

[0043] By using the above method, the clock synchronization function network element compares the error (i.e., the aforementioned second error) of the second access network device re-determined when the clock synchronization state of the first user plane function network element is abnormal with the error of the timing capability of the second access network device. If the error meets the requirements, the re-determined second error is then sent to the second access network device, which can improve the success rate of the second access network device re-determining the timing method. In conjunction with the second aspect, in some implementations of the second aspect, if the aforementioned third information also includes at least one seventh error, the method further includes: the clock synchronization function network element determining that the seventh error is less than or equal to the aforementioned second error, and at least one of the seventh errors is an error generated by at least one of the current timing methods of the aforementioned second access network device. The clock synchronization function network element sends a timing indication to the aforementioned second access network device, which instructs the aforementioned second access network device to continue timing for the aforementioned second terminal device.

[0044] Using the above method, even if the clock synchronization quality of the first user plane functional network element changes, the second access network device can continue to provide time synchronization for the second terminal device, provided that the second access network device still meets the time synchronization requirements.

[0045] Specifically, there is a one-to-one correspondence between the aforementioned sixth error and the aforementioned second access network device, but the number of the aforementioned at least one sixth error and the number of the aforementioned at least one second access network device are not necessarily the same. That is to say, the third information may not include the sixth error of each of the at least one second access network device.

[0046] Similarly, there is a one-to-one correspondence between the aforementioned seventh error and the aforementioned second access network device, but the number of the aforementioned at least one seventh error and the number of the aforementioned at least one second access network device are not necessarily the same. That is to say, the third information may not include the seventh error of each of the at least one second access network device.

[0047] In conjunction with the second aspect, in some implementations of the second aspect, if the third information includes the sixth error, the clock synchronization function network element sending the second error further includes: when the clock synchronization function network element determines that the sixth error is less than or equal to the second error, it sends the second error.

[0048] In another implementation, if the clock synchronization function network element determines that the seventh error is less than or equal to the second error, the clock synchronization function network element may also send a timing indication to the second access network device. This timing indication is used to instruct the second access network device to continue to provide timing for the second terminal device.

[0049] In conjunction with the second aspect, in some implementations of the second aspect, the above method further includes: the clock synchronization function network element receiving second information, the second information indicating that the second access network device cannot provide timing for the second terminal device, the second information being sent by the second access network device when it determines that at least one timing method supported by the second access network device cannot meet the timing requirements of the second error.

[0050] In another implementation, if the clock synchronization function network element determines, based on the fourth information, that the clock state of the first user plane function network element is abnormal, causing the second access network device to be unable to provide clock synchronization service for the second terminal device, then the clock synchronization function network element can remove the device sidetime sensitive network translator (DS-TT) function of the second terminal device from the gPTP instance.

[0051] In another implementation, if the clock synchronization of the first user plane functional network element is severely abnormal, and the aforementioned clock synchronization functional network element determines, based on the fourth information above, that most or all of the second access network devices cannot provide gPTP clock synchronization services to the terminal devices in a scenario where the clock synchronization status of the first user plane functional network element is abnormal, then the aforementioned clock synchronization functional network element deletes the gPTP instance. Alternatively, the aforementioned clock synchronization functional network element deactivates the network-side TSN protocol translation function (network-time sensitive network translator, NW-TT) and DS-TT function of the gPTP instance.

[0052] Thirdly, a clock synchronization method is provided. This method can be executed by a first access network device, by a component of the first access network device (e.g., a processor, chip, or chip system), or by a logic module or software capable of implementing all or part of the functions of the first access network device. The method includes: the first access network device sending first information indicating a change in the clock synchronization quality of the first access network device; the first access network device receiving a second error determined based on the first information; and the first access network device determining whether at least one timing method supported by the first access network device meets the timing requirements of the second error.

[0053] When the first access network device determines that at least one timing method supported by the first access network device meets the timing requirement of the second error, the first access network device determines a first timing method from at least one timing method based on the second error. The first timing method is used by the first access network core device to provide timing for the first terminal device.

[0054] When the first access network device determines that at least one timing method supported by the first access network device cannot meet the timing requirements of the second error, the first access network device sends a second message indicating that the first access network device cannot provide timing for the first terminal device.

[0055] Specifically, the aforementioned first information can be clock status notification information. It can also be information about an abnormal clock synchronization state, which could be a change in clock status, such as clock status degradation, promotion, or failure.

[0056] Specifically, at least one timing method supported by the first access network device may produce different timing errors, and a suitable timing method may be selected for timing based on the range of the second error.

[0057] By using the above methods, it is possible to determine whether the occurrence of anomalies in the communication system can still meet the requirements for timing of terminal devices, thereby improving the accuracy and stability of clock synchronization.

[0058] In conjunction with the third aspect, in some implementations of the third aspect, the aforementioned first information further includes the identifier of the aforementioned first access network device, and / or, the first information includes a first error of the first access network device, the first error being an error generated when the clock synchronization state of the first access network device is abnormal.

[0059] In conjunction with the third aspect, in some implementations of the third aspect, if the first information also includes a third error, the first access network device receiving the second error further includes: receiving the second error when the second error is less than or equal to the second error, wherein the third error is an error generated by the timing capability of the first access network device.

[0060] Specifically, the error generated by the timing capability of the first access network device can be the minimum value among the errors generated by at least one timing method supported by the first access network device, or it can be any error among the errors generated by at least one timing method supported by the first access network device. This application does not limit this.

[0061] In conjunction with the third aspect, in certain implementations of the third aspect, if the first information further includes a fourth error, and the fourth error is less than or equal to the second error, the method further includes: the first access network device receiving a timing indication, the timing indication being used to instruct the first access network device to continue timing for the first terminal device. The access network device determines the current timing method as the first timing method.

[0062] Using the above method, the first access network device can continue to provide time synchronization for the first terminal device even if the clock synchronization quality of the first access network device changes but the time synchronization requirements are still met.

[0063] When the error generated by the current timing method of the first access network device is less than or equal to the redetermined second error, that is, when the error generated by the current timing method of the first access network device is within the range of the redetermined second error, the first access network device does not need to redetermine the timing method, thus saving signaling overhead.

[0064] In another implementation, when the first information includes the fourth error, and the fourth error is less than or equal to the second error, the first access network device may not need to receive the second error. The first access network device may receive a timing indication, which instructs the first access network device to continue timing for the first terminal device.

[0065] In one implementation, if the clock synchronization state of the first access network device is abnormal, the first access network device can determine whether it still has the ability to provide time synchronization for the first terminal device based on the difference between the currently allowed error for time synchronization and the error generated when the clock synchronization state is abnormal (i.e., the aforementioned first error). If the first access network device determines that it cannot provide time synchronization service, it sends a notification to the time synchronization function network element that the first access network device cannot provide time synchronization for the first terminal device. After receiving the notification, the clock synchronization function network element sends a notification of clock degradation of the first access network device to the application function AF network element, or, after receiving the notification, the clock synchronization function network element deletes the device-side clock-sensitive network protocol translation function DS-TT of the first terminal device in the gPTP instance.

[0066] Fourthly, a communication apparatus is provided. This apparatus can be a clock synchronization function network element, a component of a clock synchronization function network element (e.g., a processor, chip, or chip system), or a logic module or software capable of implementing all or part of the clock synchronization function network element's functions. The apparatus has the capability to implement the first aspect, the second aspect, and various possible implementations of the first and second aspects. This function can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the aforementioned functions.

[0067] In one possible design, the device includes an interface unit and a processing unit. The interface unit can be at least one of a transceiver, a receiver, and a transmitter, and may include radio frequency circuitry or an antenna. The processing unit can be a processor. Optionally, the device also includes a storage unit, such as a memory. When a storage unit is included, it is used to store programs or instructions. The processing unit is connected to the storage unit and can execute the programs, instructions, or instructions stored in the storage unit to cause the device to perform the communication methods described in the first aspect, the second aspect, and various possible implementations of the first and second aspects. In this design, the device can be a clock synchronization function network element.

[0068] In another possible design, when the device is a chip, the chip includes an interface unit and a processing unit. The interface unit may be, for example, an input / output interface, pins, or circuits on the chip. The processing unit may be, for example, a processor. The processing unit can execute instructions to cause the chip within the clock synchronization function network element to perform the communication methods described above, including the first aspect, the second aspect, and any possible implementation of the first and second aspects. Optionally, the processing unit can execute instructions stored in a memory unit, which may be an on-chip memory module, such as a register or cache. The memory unit may also be located within the communication device but outside the chip, such as read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, random access memory (RAM), etc.

[0069] The processor mentioned above can be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of programs for the communication methods mentioned above.

[0070] Fifthly, a communication apparatus is provided. This apparatus may be a first access network device, a component of the first access network device (e.g., a processor, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first access network device. The apparatus has the function of implementing the third aspect and various possible implementations thereof. This function can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above-described functions.

[0071] In one possible design, the device includes an interface unit and a processing unit. The interface unit can be at least one of a transceiver, a receiver, and a transmitter, and may include radio frequency circuitry or an antenna. The processing unit can be a processor. Optionally, the device further includes a storage unit, such as a memory. When a storage unit is included, it is used to store programs or instructions. The processing unit is connected to the storage unit and can execute the programs, instructions, or instructions derived from other sources stored in the storage unit to cause the device to perform the communication methods described in the third aspect and various possible implementations thereof. In this design, the device can be a first access network device.

[0072] In another possible design, when the device is a chip, the chip includes an interface unit and a processing unit. The interface unit may be, for example, an input / output interface, pins, or circuits on the chip. The processing unit may be, for example, a processor. The processing unit can execute instructions to cause the chip within the first access network device to perform the communication methods described in the third aspect and any possible implementation of the third aspect. Optionally, the processing unit can execute instructions in a storage unit, which may be an on-chip storage module, such as a register or cache. The storage unit may also be located within the communication device but outside the chip, such as read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, random access memory (RAM), etc.

[0073] The processor mentioned above can be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of programs for the communication methods mentioned above.

[0074] In a sixth aspect, a computer storage medium is provided, wherein program code is stored therein, the program code being used to instruct instructions for performing the methods of the first aspect, the second aspect, the third aspect, and any possible implementation thereof.

[0075] In a seventh aspect, a computer program product comprising computer instructions or computer code is provided, which, when run on a computer, causes the computer to perform the methods described in the first, second, and third aspects and any possible implementations of the first, second, and third aspects.

[0076] Eighthly, a communication system is provided, comprising means having functions for implementing the methods and various possible designs of the first aspect, means having functions for implementing the methods and various possible designs of the second aspect, and means having functions for implementing the methods and various possible designs of the third aspect. The means for implementing the methods and various possible designs of the first and second aspects may be a clock synchronization function network element, and the means for implementing the functions of the third aspect and various possible designs of the third aspect may be a first access network device.

[0077] Specifically, other beneficial effects can be found in the beneficial effects described in the first, second and third aspects.

[0078] Based on the above technical solution, when the clock synchronization state of a node in a communication system is abnormal, by recalculating the timing error used by the access network equipment to determine the timing method, it is possible to determine whether the abnormality in the communication system can still meet the requirements for timing the terminal equipment, thereby improving the accuracy and stability of clock synchronization. Attached Figure Description

[0079] Figure 1 This is an example of a communication system architecture applicable to this application.

[0080] Figure 2 This is a schematic diagram of a service-oriented architecture applicable to this application.

[0081] Figure 3 This is a schematic diagram of a combination of a communication system and a TSN system provided in this application.

[0082] Figure 4 This application provides a schematic flowchart of a clock synchronization method.

[0083] Figure 5 A schematic flowchart illustrating another method for implementing clock synchronization provided in this application.

[0084] Figure 6 A schematic flowchart illustrating another clock synchronization method provided in this application.

[0085] Figure 7 This is a schematic block diagram of the device 100 for transmitting information according to this application.

[0086] Figure 8 This is a schematic block diagram of the device 100 for receiving information according to this application. Detailed Implementation

[0087] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0088] The technical solutions of this application embodiment can be applied to various communication systems, such as: Global System for Mobile Communications (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD) system, Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX) communication system, 5th Generation (5G) system or New Radio (NR) system, and future communication systems.

[0089] Figure 1 This is an example of a communication system architecture applicable to embodiments of this application. The functions of the terminal device and each network entity are described below.

[0090] Terminal equipment: can be referred to as terminal, subscriber unit, terminal station, terminal agent, terminal device, access terminal, terminal in V2X communication, user unit, user equipment (UE), user station, mobile station, mobile station (MS), remote station, remote terminal, mobile device, user terminal, wireless communication equipment, user agent, or user device.

[0091] The terminal devices in the embodiments of this application can also be mobile phones, tablets, computers with wireless transceiver capabilities, holographic projectors, video players, virtual reality (VR) terminals, augmented reality (AR) terminals, wireless terminals in industrial control, tactile terminal devices, vehicle-mounted terminal devices, roadside units (RSUs), wireless terminals in self-driving vehicles, communication terminals in drones, wireless terminals in remote medical care, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, and personal digital assistants. PDA (Power Assistant), handheld devices with wireless communication capabilities, computing devices or other processing devices connected to a wireless modem, in-vehicle devices, wearable devices, terminals in 5G networks or terminals in future evolved networks, etc.

[0092] Wearable devices, also known as wearable smart devices, are a general term for devices that utilize wearable technology to intelligently design and develop everyday wearables, such as XR headsets, gloves, watches, clothing, and shoes. Wearable devices are portable devices worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not merely hardware devices; they achieve powerful functions through software support, data interaction, and cloud interaction. Broadly defined, wearable smart devices include those with comprehensive functions, large sizes, and the ability to perform complete or partial functions without relying on a smartphone, such as smartwatches or smart glasses. They also include devices focused on a specific application function that require the use of other devices, such as smart bracelets and smart jewelry for vital sign monitoring.

[0093] Radio access network (RAN) equipment: A network composed of multiple 5G-RAN nodes, implementing radio physical layer functions, resource scheduling and radio resource management, quality of service management, data compression and encryption, radio access control, and mobility management functions. The 5G-RAN connects to the user plane function (UPF) network elements through the user plane interface N3 for transmitting data from terminal equipment; it also establishes a control plane signaling connection with the access and mobility management function (AMF) network elements through the control plane interface N2 for implementing radio access bearer control and other functions. The RAN can be any device with radio transceiver capabilities, including but not limited to 5G node base stations (gNBs), evolved Node Base Stations (eNBs), wireless access points (WiFi APs), World Interoperability for Microwave Access Base Stations (WiMAX BSs), transmission receiving points (TRPs), wireless relay nodes, and wireless backhaul nodes.

[0094] The access network device in this application embodiment can also be a device used to communicate with terminal devices. The access network device can be a base transceiver station (BTS) in a global system of mobile communication (GSM) or code division multiple access (CDMA), a base station (nodeB, NB) in a wideband code division multiple access (WCDMA) system, an evolved node base (eNB) in an LTE system, a radio controller in a cloud radio access network (CRAN) scenario, or the access network device can be a relay station, access point, vehicle-mounted equipment, wearable device, or access network equipment in a future 5G network or an access network device in a future evolved PLMN network, etc. The embodiments of this application are not limited.

[0095] In NR, the base station's functionality is divided into two parts, known as centralized unit (CU) - distributed unit (DU) separation. From a protocol stack perspective, the CU includes the RRC and PDCP layers of the LTE base station, while the DU includes the radio link control (RLC), media access control (MAC), and physical (PHY) layers. In a typical 5G base station deployment, the CU and DU are physically connected via fiber optic cable and logically share a specially defined F1 interface for communication between them. Functionally, the CU is primarily responsible for radio resource control and configuration, inter-cell mobility management, and bearer management. The DU is primarily responsible for scheduling, physical signal generation, and transmission.

[0096] Among them, the aforementioned base stations can be macro base stations, micro base stations, pico base stations, small stations, relay stations, balloon stations, etc.

[0097] Access and Mobility Management Function (AMF): This is a core network element primarily responsible for signaling processing, such as access control, mobility management, attach and detach, and gateway selection. When an AMF provides services to a session in a terminal device, it provides control plane storage resources for that session to store the session identifier and the associated Session Management Function (SMF) identifier. Furthermore, it is responsible for transmitting user policies between the terminal device and the Policy Control Function (PCF).

[0098] SMF: Primarily responsible for the control plane functions of terminal device session management, including the selection and redirection of user plane function (UPF) network elements, Internet Protocol (IP) address allocation, bearer establishment, modification, and release, as well as quality of service (QoS) control, session QoS management, and obtaining policies and charging control (PCC) policies (from PCF).

[0099] UPF network element: As the anchor point for protocol data unit (PDU) session connections, it is responsible for filtering data packets from terminal devices, transmitting / forwarding data, controlling rates, generating billing information, and providing connectivity to the data network (DN).

[0100] DN: Refers to a specific data service network that a terminal device accesses. The DN is responsible for providing operator services, internet access, or third-party services. The DN includes servers that can perform video source encoding, rendering, etc. Typical DNs include the internet and IP multi-media service (IMS) networks. In 5G networks, the DN is identified by the data network name (DNN).

[0101] Unified data management (UDM) network elements are primarily used to manage user data, such as subscription information. This includes retrieving subscription information from the unified data repository (UDR) and providing it to other network elements (e.g., AMF); generating authentication credentials for the third-generation partnership project (3GPP) for terminal devices; registering and maintaining the network elements currently serving the terminal devices, such as the AMF currently serving the terminal devices; and notifying the relevant network elements when subscription data is modified.

[0102] Network exposure function (NEF) elements expose the services and capabilities of 3GPP network functions to application functions (AF), and also allow AF to provide information to 3GPP network functions.

[0103] AF: Interacts with core network elements to provide services. For example, it interacts with PCF to control service policies, interacts with NEF to obtain network capability information or provide application information to the network, and provides data network access point information to PCF to generate routing information for corresponding data services.

[0104] PCF: Provides configuration policy information for terminal devices and provides policy information for network control plane elements (e.g., AMF, SMF) to manage and control terminal devices; generates terminal device access policies and QoS flow control policies.

[0105] Time-sensitive communication and time-synchronization function (TSCTSF) network element: Enables deterministic forwarding management capabilities within the 5G communication system.

[0106] In this embodiment, the terminal device is wirelessly connected to the RAN device, and the RAN device is wirelessly or wiredly connected to the 5G core network device. The 5G core network device and the RAN device can be independent physical devices, or the functions of the 5G core network device and the logical functions of the RAN device can be integrated into the same physical device, or a single physical device can integrate some of the functions of the 5G core network device and some of the functions of the RAN device. The terminal device can be fixed in location or mobile.

[0107] The 5G core network equipment mainly includes the aforementioned NEF network elements, PCF network elements, AF network elements, AMF network elements, SMF network elements, UPF network elements, TSCTSF network elements, etc.

[0108] It should be noted that the aforementioned "network element" can also be referred to as an entity, device, apparatus, or module, etc., and this application does not specifically limit it. Furthermore, in this application, for ease of understanding and explanation, the description of "network element" is omitted in some descriptions. For example, the TSCTSF network element is abbreviated as TSCTSF. In this case, "TSCTSF" should be understood as the TSCTSF network element or TSCTSF entity. The following descriptions of the same or similar cases are omitted.

[0109] It should be noted that, Figure 1 The names of the various network elements included are merely names and do not limit the function of the network element itself. In 5G networks and other future networks, the aforementioned network elements may also have other names, and this application embodiment does not specifically limit this. For example, in 6G networks, some or all of the aforementioned network elements may use the terminology from 5G, or they may have other names, etc. This is uniformly explained here and will not be elaborated further below.

[0110] It should be noted that, Figure 1 The various network elements in the network do not necessarily have to exist at the same time; the required network elements can be determined based on the needs. Figure 1 The connection relationships between the various network elements are not uniquely determined and can be adjusted according to requirements.

[0111] It is understood that the aforementioned network elements or functions can be network components in hardware devices, software functions running on dedicated hardware, or virtualization functions instantiated on a platform (e.g., a cloud platform).

[0112] Figure 2 This is a schematic diagram of a service-oriented architecture. (Example) Figure 2 Nnef, Nnrf, Nnssf, Naf, Npcf, Nudr, Nudm, Nausf, Namf, and Nsmf are the service interfaces provided by NEF, NRF, NSSF, AF, PCF, UDR, UDM, AUSF, AMF, and SMF, respectively, used to invoke the corresponding service operations. N1, N2, N3, N4, and N6 are interface sequence numbers.

[0113] In the above Figure 1 and Figure 2 The interface names and functions between various network elements are as follows:

[0114] 1) N1: The interface between AMF and terminal equipment, which can be used to transmit QoS control rules to the terminal.

[0115] 2) N2: The interface between AMF and RAN, which can be used to transmit radio bearer control information from the core network side to the RAN side.

[0116] 3) N3: The interface between RAN and UPF, mainly used to transmit uplink and downlink user plane data between RAN and UPF.

[0117] 4) N4: The interface between SMF and UPF, which can be used to transmit information between the control plane and the user plane, including the distribution of forwarding rules, QoS control rules, traffic statistics rules, etc. from the control plane to the user plane, as well as the reporting of information from the user plane.

[0118] 5) N5: The interface between AF and PCF, which can be used for application service request issuance and network event reporting.

[0119] 6) N6: The interface between UPF and DN, used to transmit uplink and downlink user data streams between UPF and DN.

[0120] 7) N7: The interface between PCF and SMF, which can be used to issue protocol data unit (PDU) session granularity and business data stream granularity control strategies.

[0121] 8) N8: The interface between AMF and UDM, which can be used by AMF to obtain access and mobility management related subscription data and authentication data from UDM, as well as by AMF to register terminal current mobility management related information with UDM.

[0122] 9) N9: User plane interface between UPFs, used to transmit uplink and downlink user data streams between UPFs.

[0123] 10) N10: The interface between SMF and UDM, which can be used by SMF to obtain session management-related subscription data from UDM, and by SMF to register terminal current session-related information with UDM.

[0124] 11) N11: The interface between SMF and AMF, which can be used to transmit PDU session tunnel information between RAN and UPF, transmit control messages sent to the terminal, and transmit radio resource control information sent to RAN, etc.

[0125] 12) N15: The interface between PCF and AMF, which can be used to issue terminal policies and access control related policies.

[0126] 13)Xn: The interface between two RANs, which can be used for signaling interaction between two base stations.

[0127] 14) Uu: Interface between terminal equipment and RAN.

[0128] The aforementioned network element or function can be a network component in a hardware device, a software function running on dedicated hardware, or a virtualized function instantiated on a platform (e.g., a cloud platform). Optionally, the aforementioned network element or function can be implemented by one device, multiple devices working together, or a functional module within a single device. This application does not specifically limit this aspect.

[0129] It should be understood that Figure 2 This is merely an exemplary schematic diagram of a network service architecture. The schematic diagram of the network service architecture applicable to the embodiments of this application is not limited to this. Any network service architecture that can implement the functions of the above-mentioned network elements is applicable to the embodiments of this application.

[0130] For example, in some network architectures, network function entities such as AMF, SMF, PCF, TSCTSF, and UDR are all called network function (NF) network elements; or, in other network architectures, a collection of network elements such as AMF, SMF, PCF, TSCTSF, and UDM can be called control plane function (CPF) network elements.

[0131] The following section uses network elements in a 5G system (5GS) as an example to introduce specific solution details. It is understood that when this solution is used in LTE systems, 5G systems, or future communication systems, the network elements in the solution can be replaced with other network elements that have corresponding functions; this application does not impose any limitations on this.

[0132] It should be understood that Figure 1 and Figure 2This is merely an exemplary network architecture, and the network architecture applicable to the embodiments of this application is not limited thereto. Any network architecture capable of implementing the functions of the above-mentioned network elements is applicable to the embodiments of this application.

[0133] This application uses a 5G communication system as an example to describe the embodiments of this application, but the technical solutions of this application are not limited to 5G systems.

[0134] In fields such as communications and industrial control, all tasks are based on a clock reference; therefore, accurate clock synchronization is a fundamental standard. TSN (Time Sequencing) is a mature, widely used industrial standard defined by the Institute of Electrical and Electronics Engineers (IEEE). TSN solves the problems of clock synchronization and latency calculation in networks, ensuring high consistency in task scheduling across the entire network. Many vertical industry users hope that their wired access in TSN networks can be replaced by 5G networks. Therefore, when users access TSN networks through 5G systems, they can both utilize the existing control functions of TSN networks and meet various performance indicators for TSN network data transmission through 5G systems.

[0135] In order to support TSN, 5G systems also need to support clock synchronization. For example... Figure 3 As shown, the network-side TSN protocol translation function (network-time sensitive network translator, NW-TT) of the 5G system is the input interface to the TSN system, responsible for introducing the TSN clock synchronization message into the 5G network. NW-TT needs to synchronously complete the measurement of latency deviation and frequency deviation between the 5G system and TSN. Additionally, NW-TT adds the 5G system's clock stamp (TSE or TSI) to the synchronization clock message. NW-TT can be an interface of the 5G system's network-side UPF or a function integrated into the UPF.

[0136] The device sidetime sensitive network translator (DS-TT) function of the 5G system acts as the outgoing interface to the TSN system. It is responsible for outputting TSN clock synchronization messages to the TSN. DS-TT needs to work with the TSN end station to synchronize and measure the latency and frequency deviation between the 5G system and the TSN. Additionally, DS-TT adds a 5G system clock stamp (TSE) to the synchronization clock message and calculates the 5G system's internal residence time. DS-TT can be an interface on the UE (User Equipment) side of the 5G system terminal equipment or a function integrated into the UE.

[0137] In summary, the clock synchronization process in the TSN system and the 5G system is as follows: The TSN clock source (greenwich mean, GM) of the TSN system sends gPTP messages to the 5G system. The clock information of the TSN system is carried in the generalized precision time protocol (gPTP) message. This message is transmitted via a session (e.g., Figure 3 In the data streams of Session 1, Session 2, and Session 3 shown, data is transmitted from NW-TT to DS-TT. Based on the clock stamp information in the gPTP message, the UE calculates the deviation between the 5G system clock and the TSN system clock, and finally obtains the clock information of the TSN system.

[0138] A 5G system can be viewed as a bridge in a TSN (Tracking Network Service), or as a Precision Time Protocol (PTP) node in a TSN. The DS-TT calculation of clock synchronization messages requires the 5G system to operate within a single time domain and maintain consistent frequencies to minimize forwarding latency.

[0139] The TSN system clock domain can be a factory-defined clock source and does not necessarily have to be consistent with the Global Positioning System (GPS) or Coordinated Universal Time (UTC).

[0140] Among them, it can be considered that Figure 3 Each gPTP instance in the 5G system shown includes multiple terminal devices.

[0141] The technical solution of this application can be applied not only to standalone 5G communication systems, but also to combined systems of 5G communication systems and other systems, such as the combination of the 5G system described above with a time-sensitive network (TSN).

[0142] For a standalone 5G system, the clock synchronization method (or timing method) of the 5G system is broadcast to the UE by the RAN through air interface frame alignment, and the UE can calculate the accurate 5G clock information locally. The UPF calculates the accurate 5G clock information locally using the 5G clock information provided by the RAN or transport network.

[0143] For the combined 5G and TSN systems described above, the TSN clock source sends gPTP messages to each gPTP node in the TSN system, and the 5G system can also be considered a gPTP node in the TSN system. In other words, for the TSN system to obtain accurate TSN clock information, precise clock synchronization with the 5G system within the TSN system is essential.

[0144] There is currently no solution for determining whether the 5G system can still meet the requirements for timing the UE when an anomaly occurs in the RAN or UPF of a 5G system during clock synchronization.

[0145] In this application, an anomaly occurring during clock synchronization in the RAN or UPF can be a degradation, promotion, or fault, and the scenario for this anomaly is not limited. To more clearly illustrate the technical solution of this application, this application uses degradation as an example, where degradation can be a clock delay in the RAN or UPF.

[0146] For standalone 5G networks, this application provides a method for achieving more accurate clock synchronization, such as... Figure 4 As shown.

[0147] In step S410, the 5G system provides access layer clock synchronization service to the UE.

[0148] Specifically, the AF can send a timing request message to the NEF, which then forwards it to the TSCTSF. This timing request message includes the UE's identifier. Optionally, the timing request may include the AF's timing error budget requirement (i.e., error #1 as described below).

[0149] Specifically, error #1 can be the maximum upper limit requirement of the 5G system for UE timing error.

[0150] If error #1 is not carried in the aforementioned timing request message, TSCTSF can use the pre-configured default value as error #1. After obtaining the aforementioned error #1, TSCTSF removes the timing errors of the network side and the device side (i.e., error #2 as described below) from error #1 according to the clock synchronization method, and can obtain the timing error of the Uu air interface (i.e., error #3 as described below).

[0151] Specifically, the aforementioned error #2 can be a pre-configured value or a value transmitted in other ways, which is not limited in this application.

[0152] TSCTSF will send the determined error #3 to RAN, which will then determine which timing method to use for UE timing.

[0153] Specifically, the UE can obtain the RAN reference clock signal using various timing methods, such as round trip latency (RTT) and time advance (TA), but this application does not limit the specific methods.

[0154] Step S412, the RAN clock state is abnormal.

[0155] Specifically, an abnormality in the RAN clock state can be caused by a change in the RAN clock state. For example, the RAN clock state may be degraded, upgraded, or malfunctioning. For instance, when the reference clock signal sent by the global navigation satellite system (GNSS) to the RAN is blocked by an obstacle, the GNSS receiving antenna on the RAN side may not receive the reference clock signal in time, resulting in a change in the RAN clock state.

[0156] The embodiments of this application take clock state degradation as an example. The clock state upgrade or clock state failure are similar to the clock state degradation.

[0157] In step S414, the RAN sends information #1 to the AMF through the Next Generation Application Protocol (NGAP) service. This information #1 is used to notify the RAN that the clock state has become abnormal.

[0158] Specifically, the aforementioned information #1 can be an example of the first information.

[0159] Specifically, the aforementioned information #1 may include information about changes in the RAN's clock quality.

[0160] Optionally, the aforementioned information #1 may also include the RAN identifier, error #4, error generated by the RAN's timing capability (i.e., an example of the third error), the timing method currently used by the RAN and the error generated by that currently used timing method (i.e., an example of the fourth error), and the timing error of at least one timing method currently supported by the RAN. Error #4 is an error generated / caused by an abnormal RAN clock state, or error #4 may be an increased error range (uncertainty, UTC traceability, or clock quality information) when the RAN clock state is abnormal. Specifically, error #4 may be an example of the first error.

[0161] Specifically, the error generated by the RAN's timing capability can be the minimum error generated by at least one timing method supported by the RAN, or it can be any error generated by at least one timing method supported by the RAN. This application does not limit this.

[0162] In step S416, AMF forwards the above information #1 to TSCTSF.

[0163] Specifically, the AMF can forward the aforementioned information #1 to the TSCTSF through the SMF, the AMF can also forward the aforementioned information #1 to the TSCTSF through the PCF, and the AMF can also forward the aforementioned information #1 to the TSCTSF through the SMF and PCF. This application does not limit this.

[0164] In step S418, the TSCTSF can subscribe to information #1 in advance to the operation administration and maintenance (OAM) network element. When the clock state of the RAN is abnormal, the OAM reports the above information #1 to the TSCTSF.

[0165] Optionally, in step S420, if the RAN clock state is abnormal and the RAN does not report information #1 to the TSCTSF, then the OAM sends information #1 subscription response message to the TSCTSF, which includes the aforementioned information #1.

[0166] In step S422, the TSCTSF performs a first determination, which is used by the TSCTSF to determine whether the RAN can still provide access layer clock synchronization services to the UE in a degraded scenario.

[0167] Specifically, the first determination can have the following results:

[0168] The first method: Specifically, TSCTSF recalculates the aforementioned error #3 and designates the recalculated error #3 as error #5. This error #5 is then sent to the RAN.

[0169] Specifically, error #5 could be an example of the second error.

[0170] Alternatively, if information #1 also includes an error caused by the RAN's timing capability (i.e., an example of the third error), TSCTSF also needs to determine whether the aforementioned error #5 is within the range of errors caused by the RAN's timing capability. If so, then error #5 is sent to the RAN.

[0171] For example, if error #3 is 250 nanoseconds (ns), the best timing error that the RAN can provide (i.e., the error generated by the timing capability of the RAN) is 100 ns, and error #4 is 100 ns, then TSCTSF can confirm error #5 as error #3 - error #4 = 150 ns, and the best timing error that the RAN can provide is 100 ns < 150 ns. TSCTSF can determine that the RAN's capability can still provide access layer clock synchronization service to the UE in a degraded scenario.

[0172] Thirdly: Optionally, if information #1 also includes an error caused by the RAN's timing capability (i.e., an example of the third error), TSCTSF also needs to determine whether the aforementioned error #5 is within the range of errors caused by the RAN's timing capability. If not, then error #5 will not be sent to the RAN.

[0173] Fourthly: Optionally, if information #1 also includes the timing method currently used by the RAN and the error generated by that timing method (i.e., an example of the fourth error), the TSCTSF also needs to determine whether the aforementioned error #5 is within the range of the timing method currently used by the RAN and the error generated by that timing method. If so, then error #5 is not sent to the RAN, but the RAN is instructed to use the current timing method to time the UE.

[0174] Fifthly: Optionally, if information #1 also includes the timing method currently used by the RAN and the error generated by that timing method (i.e., an example of the fourth error), TSCTSF also needs to determine whether the aforementioned error #5 is within the range of the timing method currently used by the RAN and the error generated by that timing method. If not, then error #5 is sent to the RAN, and the RAN redetermines the timing method.

[0175] Sixth: Optionally, if information #1 includes errors caused by the RAN's timing capability (i.e., an example of the third error) and the timing method currently used by the RAN and the errors caused by the currently used timing method (i.e., an example of the fourth error), TSCTSF may make a determination using any one of the second, third, fourth, and fifth methods described above.

[0176] In step S424, if the TSCTSF needs to send the recalculated error #5 or timing indication to the RAN, the TSCTSF sends information #2 to the RAN, which includes the error #5 or timing indication that needs to be sent to the RAN.

[0177] Specifically, the TSCTSF needs to forward the above information #2 to the RAN through SMF and AMF, or the TSCTSF needs to forward the above information #2 to the RAN through PCF and AMF. This application does not limit the specifics of the above information #2 sent by the TSCTSF to the RAN through PCF, SMF and AMF.

[0178] In step S426, after receiving information #2, the RAN can determine the timing method #1 that meets the error #5 requirement (i.e., an example of the first timing method) based on information #2, or it can select the currently used timing method based on the timing instruction.

[0179] In step S428, the RAN provides timing for the UE according to the determined timing method #1, or the RAN continues to provide timing for the UE using the currently used timing method.

[0180] Optionally, in step S430, if the RAN cannot determine the timing method #1 that meets the error #5 requirement based on information #2, or the RAN cannot provide the timing method #1 that meets the error #5 requirement, then the RAN sends a RAN timing failure notification to the TSCTSF (i.e., an example of the second information).

[0181] Optionally, in step S432, if the TSCTSF determines, based on the result of the first determination above, that the RAN cannot provide access layer clock synchronization service to the UE in the degraded scenario, then it directly sends a RAN degrade notification to the AF.

[0182] Specifically, step S432 can be performed after step S422 and before step S424. When step S432 is performed, steps S424 to S430 do not need to be performed.

[0183] Through the technical solutions of the above embodiments, in the scenario where the clock state of the RAN for access layer clock synchronization is abnormal, the timing method of the RAN for the UE can be updated and adjusted in a timely manner, thereby improving the accuracy of clock synchronization.

[0184] The previous section described a RAN-UE time synchronization scenario in a 5G system. The following section uses a combined 5G and TSN system as an example to introduce technical solutions for multiple RAN degradation scenarios in gPTP node clock synchronization, such as... Figure 5 As shown.

[0185] A gPTP instance may include multiple RANs or multiple terminal devices. This embodiment describes the technical solution in detail with the example of a gPTP instance including two RANs (e.g., RAN1 and RAN2).

[0186] In step S510, the 5G system provides gPTP clock synchronization service to the UE.

[0187] For specific synchronization methods, please refer to the description of the access layer clock synchronization service in step S410, which will not be repeated here.

[0188] Steps S512 to S514 can be referred to steps S412 to S414, and will not be repeated here.

[0189] In step S516, when the AMF receives information #1 from RAN1, if it can determine that UE2 and UE1, which are time-synchronized with RAN1, belong to the same gPTP instance, it can send information #3 to TSCTSF at the same time as forwarding information #1 to TSCTSF.

[0190] Specifically, the aforementioned information #1 and information #3 can be sent together in the same information #5.

[0191] Specifically, the aforementioned information #3 may include the identifier of RAN2, the error caused by the timing capability of RAN2, the timing method currently used by RAN2 and the error caused by the currently used timing method, the timing error of at least one timing method currently supported by RAN2, etc.

[0192] The descriptions of steps S518 to S520 can be found in steps S418 to S420, and will not be repeated here.

[0193] In step S522, the TSCTSF can subscribe to information #3 in advance to the operation administration and maintenance (OAM) network element.

[0194] Specifically, information #3 can represent the timing information of all RANs participating in UE timing within the same gPTP instance.

[0195] Optionally, in step S524, after receiving information #1 from RAN1, TSCTSF can determine whether there are other RANs participating in the UE's timing in the same gPTP instance as RAN1. If it is found that RAN2 is also participating in timing, TSCTSF obtains the aforementioned information #3 of RAN2 from the OAM network element.

[0196] In step S526, after receiving information #5, the TSCTSF performs a second determination, which is used by the TSCTSF to determine whether RAN1 can still provide gPTP clock synchronization service to UE1 in a degraded scenario.

[0197] Specifically, the determination of RAN1 can refer to the first determination in step S422 above.

[0198] Specifically, the determination of RAN2 can refer to the determination process of the second, third, fourth, fifth and sixth determinations in step S422 above.

[0199] In step S528, if the TSCTSF needs to send the recalculated error #5 or timing indication to RAN1, the TSCTSF sends information #2 to the AMF, which includes the error #5 or timing indication to be sent to RAN1. If the TSCTSF needs to send the recalculated error #5 or timing indication to RAN2, the TSCTSF sends information #4 to the AMF, which includes the error #5 or timing indication to be sent to RAN2.

[0200] In step S530, AMF sends information #2 to RAN1.

[0201] Steps S532 to S536 can be referred to as steps S426 to S430 above, and will not be repeated here.

[0202] In step S538, AMF sends information #4 to RAN2.

[0203] Steps S540 to S544 can be referred to as steps S426 to S430 above, and will not be repeated here.

[0204] Optionally, in step S546, if the TSCTSF determines, based on the result of the second determination above, that RAN1 cannot provide gPTP clock synchronization service to UE1 in the degraded scenario, then the DS-TT of UE1 is removed from the gPTP instance.

[0205] Specifically, step S546 can be performed after step S526 and before step S528. When step S546 is performed, steps S530 to S536 do not need to be performed.

[0206] Through the technical solution of the above embodiments, when the RAN degrades, the timing error budget of other RANs participating in UE timing in the gPTP instance is also updated synchronously. This not only ensures that the clock synchronization information is updated in a timely manner, but also ensures that the clock information of the time-synchronized terminal devices in a gPTP instance remains consistent.

[0207] The previous section introduced technical solutions for various RAN degradation scenarios in gPTP node clock synchronization. The following section introduces technical solutions for UPF degradation scenarios in gPTP node clock synchronization, such as... Figure 6 As shown.

[0208] In step S610, the 5G system provides gPTP clock synchronization service to the UE.

[0209] For specific synchronization methods, please refer to the description of the access layer clock synchronization service in step S410, which will not be repeated here.

[0210] Step S612, UPF clock state is abnormal.

[0211] Specifically, an abnormality in the UPF clock state can be caused by a change in the UPF clock state. For example, the UPF clock state may be downgraded, upgraded, or malfunction.

[0212] The embodiments of this application take clock state degradation as an example. The clock state upgrade or clock state failure are similar to the clock state degradation.

[0213] In step S614, the UPF sends message #6 to the TSCTSF, which is used to notify the UPF that the clock state has become abnormal.

[0214] Specifically, the aforementioned information #6 can be an example of the first information.

[0215] Specifically, information #6 above may include information about changes in the clock quality of the UPF.

[0216] Optionally, the information #6 above may also include the UPF identifier and error #6. Error #6 is the error generated / caused by an abnormal clock state of the UPF, or it may be the increased error range (uncertainty, UTC traceability) when the UPF's clock state is abnormal. Specifically, error #6 may be an example of the first error.

[0217] In step S618, the TSCTSF can subscribe to information #6 in advance to the operation administration and maintenance (OAM) network element. When the clock state of the UPF is abnormal, the OAM reports the above information #6 to the TSCTSF.

[0218] Optionally, in step S620, if the clock state of the UPF is abnormal and the UPF does not report information #6 to the TSCTSF, then the OAM sends an information #6 subscription response message to the TSCTSF, which includes the aforementioned information #6.

[0219] In step S622, the TSCTSF can subscribe to information #3 in advance to the operation administration and maintenance (OAM) network element.

[0220] Specifically, information #3 can represent the timing information of all RANs participating in UE timing within the same gPTP instance.

[0221] Optionally, in step S624, after receiving information #6 from the UPF, the TSCTSF can determine the timing information of all RANs participating in timing in the gPTP instance of the downgraded UPF. For example, RAN1 and RAN2 are participating in timing in this gPTP instance. The TSCTSF obtains the aforementioned information #3 of RAN1 and RAN2 from the OAM network element.

[0222] In step S626, after receiving information #6, the TSCTSF performs a third determination, which is used by the TSCTSF to determine whether RAN1 and RAN2 can still provide gPTP clock synchronization services for UE1 and UE2 in a downgraded scenario.

[0223] Specifically, the third decision for RAN1 can yield the following results:

[0224] The first method, specifically, involves TSCTSF recalculating the aforementioned error #3 and designating the recalculated error #3 as error #5. This error #5 is then sent to RAN1.

[0225] Specifically, error #5 could be an example of the second error.

[0226] For other results of the RAN1 determination, refer to the determination process of the second, third, fourth, fifth and sixth determinations of the first determination in step S422 above.

[0227] Specifically, the third decision for RAN2 can yield the following results:

[0228] The first method, specifically, involves TSCTSF recalculating the aforementioned error #3 and designating the recalculated error #3 as error #5. This error #5 is then sent to RAN2.

[0229] Specifically, error #5 could be an example of the second error.

[0230] For other results of the RAN2 determination, refer to the determination process of the second, third, fourth, fifth and sixth determinations in step S422 above.

[0231] In step S628, if the TSCTSF needs to send the recalculated error #5 or timing indication to RAN1, the TSCTSF sends information #7 to the AMF, which includes the error #5 or timing indication to be sent to RAN1. If the TSCTSF needs to send the recalculated error #5 or timing indication to RAN2, the TSCTSF sends information #4 to the AMF, which includes the error #5 or timing indication to be sent to RAN2.

[0232] In step S630, AMF sends information #7 to RAN1.

[0233] Steps S632 to S636 can be referred to as steps S426 to S430 above, and will not be repeated here.

[0234] In step S638, AMF sends information #4 to RAN2.

[0235] Steps S640 to S644 can be referred to as steps S426 to S430 above, and will not be repeated here.

[0236] Optionally, in step S646, if the TSCTSF determines, based on the result of the third determination, that RAN1 cannot provide gPTP clock synchronization service to UE1 in the UPF downgrade scenario, then the DS-TT of UE1 is removed from the gPTP instance. Alternatively, if the TSCTSF determines, based on the result of the third determination, that RAN2 cannot provide gPTP clock synchronization service to UE2 in the UPF downgrade scenario, then the DS-TT of UE2 is removed from the gPTP instance.

[0237] Specifically, step S646 can be performed after step S626 and before step S628. When step S646 is performed, steps S630 to S636 or steps S638 to S644 do not need to be performed.

[0238] Optionally, in step S648, if the UPF degradation is severe, and the TSCTSF determines, based on the result of the third determination above, that most or all of the RANs cannot provide gPTP clock synchronization services to the UE in the UPF degradation scenario, then the gPTP instance is deleted. Alternatively, the TSCTSF deactivates the NW-TT and DS-TT functions.

[0239] Optionally, in step S650, if the TSCTSF deletes the gPTP instance, it sends a UPF downgrade notification to the AF.

[0240] Through the technical solution of the above embodiments, when the UPF in a gPTP instance is downgraded, the timing error budget of other RANs participating in timing in the gPTP instance is also updated synchronously. This not only ensures that the clock synchronization information is updated in a timely manner, but also ensures that the clock information of the time-synchronized terminal devices in a gPTP instance can remain consistent.

[0241] Figure 7 A schematic block diagram of a means 100 for transmitting information according to an embodiment of this application is shown. This means 100 may correspond to (e.g., may be configured in or be itself) the above-described means. Figure 4 , Figure 5 , Figure 6 The embodiments describe UPF, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM, and each module or unit in the information transmission device 100 is used to perform the above-described functions. Figure 4 , Figure 5 , Figure 6 The specific actions or processes performed by UPF, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM described in the embodiments are omitted here to avoid redundancy.

[0242] In this embodiment of the application, the device 100 can be Figure 4 , Figure 5 , Figure 6 The embodiments described include UPF, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM. In this case, the device 100 may include a processor and a transceiver, which are communicatively connected.

[0243] Optionally, the device further includes a memory that is communicatively connected to the processor. Optionally, the processor, the memory, and the transceiver can be communicatively connected. The memory can be used to store programs or instructions, and the processor can be used to execute the programs or instructions stored in the memory to control the transceiver to send information or signals.

[0244] In this case, Figure 7 The interface unit in the device 100 shown can correspond to the transceiver. Figure 7 The processing unit in the device 100 shown can correspond to the processor.

[0245] In this embodiment of the application, the device 100 can be installed on Figure 4 , Figure 5 , Figure 6The embodiments describe chips (or chip systems) among UPF, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM. In this case, the device 100 may include a processor and an input / output interface, the processor of which can communicate with... Figure 4 , Figure 5 , Figure 6 The transceiver communication connections described in the embodiments for UPF, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM may optionally include a memory communicatively connected to a processor. Alternatively, the processor, memory, and transceiver may be communicatively connected; the memory may be used to store programs or instructions, and the processor may be used to execute the programs or instructions stored in the memory to control the transceiver to transmit information or signals.

[0246] In this case, Figure 7 The interface unit in the device 100 shown can correspond to the input / output interface. Figure 7 The processing unit in the device 100 shown can correspond to the processor.

[0247] Figure 8 The diagram shows a schematic block diagram of an information receiving device 200 according to an embodiment of this application. This information receiving device 200 can correspond to (e.g., can be configured to implement) the above-described... Figure 4 , Figure 5 , Figure 6 The embodiments describe UPF, UE1, UE2, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM, and each module or unit in the information receiving device 200 is used to perform the above-described functions. Figure 4 , Figure 5 , Figure 6 The specific actions or processes performed by UPF, UE1, UE2, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM described in the embodiments are omitted here to avoid redundancy.

[0248] In this embodiment of the application, the device 200 can be Figure 4 , Figure 5 , Figure 6The embodiments describe UPF, UE1, UE2, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM. In this case, the device 200 may include a processor and a transceiver, which are communicatively connected. Optionally, the device may also include a memory, which is communicatively connected to the processor. Optionally, the processor, memory, and transceiver may be communicatively connected. The memory may be used to store programs or instructions, and the processor may be used to execute the programs or instructions stored in the memory to control the transceiver to receive information or signals.

[0249] In this case, Figure 8 The interface unit in the device 200 shown can correspond to the transceiver. Figure 8 The processing unit in the device 200 shown can correspond to the processor.

[0250] In this embodiment of the application, the device 200 can be installed on Figure 4 , Figure 5 , Figure 6 The embodiments describe chips (or chip systems) among UPF, UE1, UE2, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM. In this case, the device 200 may include a processor and an input / output interface, the processor of which can communicate with... Figure 4 , Figure 5 , Figure 6 The transceiver communication connections described in the embodiments for UPF, UE1, UE2, RAN1, RAN2, AMF, PCF, TSCTSF, NEF, AF, and OAM may optionally include a memory communicatively connected to a processor. Alternatively, the processor, memory, and transceiver may be communicatively connected; the memory may be used to store programs or instructions, and the processor may be used to execute the programs or instructions stored in the memory to control the transceiver to receive information or signals.

[0251] In this case, Figure 8 The interface unit in the device 200 shown can correspond to the input interface. Figure 8 The processing unit in the device 200 shown can correspond to the processor.

[0252] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for specific applications, but such implementations should not be considered beyond the scope of this application.

[0253] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0254] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0255] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0256] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0257] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0258] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A clock synchronization method, characterized in that, include: The clock synchronization function network element receives first information from the first device, the first information being used to indicate a change in the clock synchronization quality of the first access network device; The clock synchronization function network element determines the first error of the first access network device based on the first information, and determines whether the first error meets the total timing error configured by the network for the first service. The total timing error is used by the first access network device to provide timing for the first terminal device. The first error is the error generated when the clock quality of the first access network device changes.

2. The method according to claim 1, characterized in that, When the first error does not meet the total timing error configured by the network for the first service, the method further includes: The clock synchronization function network element determines the second error of the first access network device based on the first information. The second error is used by the first access network device to provide time synchronization for the first terminal device. The clock synchronization function network element sends the second error to the first access network device.

3. The method according to claim 2, characterized in that, The first information also includes the identifier of the first access network device.

4. The method according to claim 3, characterized in that, The first device includes the first access network device, a mobility management network element (AMF), or an operation and maintenance management (OAM) device.

5. The method according to any one of claims 2 to 4, characterized in that, If the first information also includes a third error, the clock synchronization function network element sending the second error to the first access network device further includes: the clock synchronization function network element sending the second error when it determines that the third error is less than or equal to the second error, wherein the third error is an error generated by the timing capability of the first access network device.

6. The method according to any one of claims 2 to 4, characterized in that, If the first information further includes a fourth error, the method further includes: The clock synchronization function network element determines that the fourth error is less than or equal to the second error, and the fourth error is the error generated by the current timing method of the first access network device. The clock synchronization function network element sends a timing indication to the first access network device, the timing indication being used to instruct the first access network device to use the current timing method to synchronize the time of the first terminal device.

7. The method according to any one of claims 2 to 4, characterized in that, The method further includes: The clock synchronization function network element receives second information, which indicates that the first access network device cannot provide time synchronization for the first terminal device. The second information is sent by the first access network device when it determines that at least one time synchronization method supported by the first access network device cannot meet the time synchronization requirements of the second error.

8. The method according to any one of claims 2 to 4, characterized in that, The method further includes: The clock synchronization function network element determines at least one second access network device, the at least one second access network device provides time synchronization for at least one second terminal device, and at least one second terminal device and the first terminal device belong to the same General Precision Clock Protocol (gPTP) instance. The clock synchronization function network element sends the second error to at least one of the second access network devices.

9. The method according to claim 8, characterized in that, The method further includes: The clock synchronization function network element receives third information from the second device, the third information being used to indicate at least one of the second access network devices, the second device including a mobility management network element or an operation and maintenance management (OAM) device.

10. A method for clock synchronization, characterized in that, include: The clock synchronization function network element receives fourth information from the third device, the fourth information being used to indicate a change in the clock synchronization quality of the first user plane function network element; The clock synchronization function network element determines the fifth error of at least one second access network device based on the fourth information, and determines whether the fifth error satisfies at least one total timing error configured by the network for at least one first service. At least one first service corresponds one-to-one with at least one of the total timing errors. The fifth error is the error generated when the clock quality of the first user plane function network element changes.

11. The method according to claim 10, characterized in that, When the fifth error does not meet the total timing error configured by the network for the first service, the method further includes: The clock synchronization function network element determines a second error of at least one second access network device according to the fourth information. The second error is used by at least one second access network device to provide time synchronization for at least one second terminal device. At least one second terminal device belongs to a common precision clock protocol gPTP instance. The clock synchronization function network element sends the second error to the second access network device.

12. The method according to claim 10, characterized in that, The fourth piece of information also includes the identifier of the first user plane function network element.

13. The method according to claim 10, characterized in that, The third device includes the first user plane function network element or operation, maintenance and management (OAM) equipment.

14. The method according to claim 11, characterized in that, The method further includes: The clock synchronization function network element receives third information from the operation, maintenance and management (OAM) equipment, the third information being used to instruct at least one of the second access network devices.

15. The method according to claim 14, characterized in that, If the third information includes at least one sixth error, the clock synchronization function network element sending the second error to the second access network device further includes: the clock synchronization function network element sending the second error when it determines that the sixth error is less than or equal to the second error, wherein at least one of the sixth errors is an error generated by the timing capability of at least one of the second access network devices.

16. The method according to claim 14, characterized in that, If the third information further includes at least one seventh error, and the seventh error is less than or equal to the second error, the method further includes: The clock synchronization function network element determines that the seventh error is less than or equal to the second error, and at least one of the seventh errors is an error generated by the current timing method of at least one second access network device; The clock synchronization function network element sends a timing indication to the second access network device, the timing indication being used to instruct the second access network device to use the current timing method to synchronize the time of the second terminal device.

17. The method according to any one of claims 11 to 16, characterized in that, The method further includes: The clock synchronization function network element receives second information, which indicates that the second access network device cannot provide time synchronization for the second terminal device. The second information is sent by the second access network device when it determines that at least one time synchronization method supported by the second access network device cannot meet the time synchronization requirements of the second error.

18. The method according to claim 17, characterized in that, The method further includes: The clock synchronization function network element removes the device-side clock-sensitive network protocol translation function DS-TT from the second terminal device in the gPTP instance.

19. A clock synchronization method, characterized in that, include: The first access network device sends first information, which is used to indicate a change in the clock synchronization quality of the first access network device. The first access network device receives a second error, which is determined based on the first information; The first access network device determines whether at least one timing method supported by the first access network device meets the timing requirements of the second error; When the first access network device determines that at least one timing method supported by the first access network device meets the timing requirement of the second error, the first access network device determines a first timing method from at least one timing method according to the second error, and the first timing method is used by the first access network core device to provide timing for the first terminal device; When the first access network device determines that at least one timing method supported by the first access network device cannot meet the timing requirements of the second error, the first access network device sends second information, the second information indicating that the first access network device cannot provide timing for the first terminal device.

20. The method according to claim 19, characterized in that, The first information also includes the identifier of the first access network device, and / or the first information includes a first error of the first access network device, which is an error generated when the clock quality of the first access network device changes.

21. The method according to claim 19, characterized in that, If the first information also includes a third error, the first access network device receiving the second error further includes: receiving the second error when the third error is less than or equal to the second error, wherein the third error is an error generated by the timing capability of the first access network device.

22. The method according to any one of claims 19 to 21, characterized in that, If the first information further includes a fourth error, and the fourth error is less than or equal to the second error, the method further includes: The first access network device receives a timing indication, which is used to instruct the first access network device to use the current timing method to provide timing for the first terminal device, and the fourth error is the error generated by the current timing method of the first access network device. The first access network device determines the current timing method as the first timing method according to the timing instruction.

23. A communication device, characterized in that, include: A processor coupled to a memory for storing programs or instructions that, when executed by the processor, cause the apparatus to perform the clock synchronization method as described in any one of claims 1 to 22.

24. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when run on a computer, causes the computer to perform the clock synchronization method as described in any one of claims 1 to 22.

25. A computer program product, characterized in that, It includes computer program code that, when run, implements the clock synchronization method as described in any one of claims 1 to 22.

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