WO2023051620A1

WO2023051620A1 - Communication method, communication apparatus and communication system

Info

Publication number: WO2023051620A1
Application number: PCT/CN2022/122180
Authority: WO
Inventors: 臧昕; 周润泽; 王远
Original assignee: 华为技术有限公司
Priority date: 2021-09-30
Filing date: 2022-09-28
Publication date: 2023-04-06
Also published as: CN115915219A

Abstract

Provided in the present application are a communication method, a communication apparatus and a communication system. The method comprises: a first network element receiving time requirement information from a second network element; the first network element acquiring time information of a first clock according to the time requirement information, wherein the first clock is a clock which matches the time requirement information among a plurality of clocks of the first network element; and the first network element sending the time information of the first clock to the second network element. In the solution, information of a plurality of clocks is stored in a first network element, such that when a certain clock has a fault, other clocks may still be used, thereby avoiding a situation in which accurate time information cannot be provided externally. In addition, since the information of the plurality of clocks is stored in the first network element, the first network element may provide, to a second network element and on the basis of time requirement information that is sent by the second network element, time information of a clock that best matches the time requirement information, such that accurate time information can be provided.

Description

A communication method, communication device and communication system

Cross References to Related Applications

This application claims the priority of the Chinese patent application with the application number 202111160112.X and the application title "a communication method, communication device and communication system" submitted to the China Patent Office on September 30, 2021, the entire contents of which are incorporated by reference incorporated in this application.

technical field

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

Background technique

The fifth generation (the 5th generation, 5G) network manages the information of a clock, and the 5G network has the ability to serve time, and can provide the time information of the clock to the outside world.

However, when the clock fails, the precise time information of the clock cannot be provided externally.

Contents of the invention

Embodiments of the present application provide a communication method, a communication device, and a communication system, so as to provide time information.

In a first aspect, the embodiment of the present application provides a communication method, the method may be executed by a first network element or a module (such as a chip) in the first network element, and the first network element may be a clock network function network element. Taking the execution of the method by the first network element as an example, the method includes: the first network element receives time requirement information from the second network element; the first network element acquires time information of the first clock according to the time requirement information, and the The first clock is a clock matching the time requirement information among the multiple clocks of the first network element; the first network element sends the time information of the first clock to the second network element.

According to the above scheme, since information of multiple clocks is stored on the first network element, when a certain clock fails, other clocks can be used to avoid the situation that the accurate time information cannot be provided externally. Moreover, since the information of multiple clocks is stored on the first network element, the first network element can provide the second network element with the time of a clock that best matches the time requirement information based on the time requirement information sent by the second network element Information, can provide accurate time information.

As a possible implementation method, the first network element continuously sends the time information of the first clock to the second network element according to a set period.

According to the above solution, the first network element can keep the second network element synchronized with the first clock by continuously sending the time information of the first clock to the second network element.

As a possible implementation method, the first network element receives the time keeping capability of the second network element from the second network element, and the time keeping capability of the second network element indicates that the second network element loses a clock source signal Afterwards, the precise time is continuously provided for a period of time; the first network element sends the time information of the first clock to the second network element according to the time keeping capability of the second network element.

According to the above solution, on the one hand, the second network element can be synchronized with the first clock, and on the other hand, the signaling overhead for the first network element to send the time information of the first clock to the second network element can be reduced.

As a possible implementation method, the first network element determines the time information of at least two clocks among the plurality of clocks according to the time requirement information, and the at least two clocks both match the time requirement information; the first network element The element selects the first clock from the at least two clocks.

As a possible implementation method, the first network element sends configuration information of the first clock to the second network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, the second One or more of the time keeping capability of a clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock.

As a possible implementation method, the time requirement information includes one or more of the following information: clock source, clock accuracy, clock time keeping capability or service area.

As a possible implementation method, the second network element is an application function network element, a terminal device, an access network device or a core network device.

In the second aspect, the embodiment of the present application provides a communication method, which can be performed by a second network element or a module (such as a chip) in the second network element, and the second network element can be a terminal device, an access network equipment, core network equipment, or application function network element. The method includes: the second network element sends time requirement information to the first network element; the second network element receives time information from a first clock of the first network element, and the first clock is a multiple clock of the first network element The clock that matches the time requirement information among the clocks.

According to the above scheme, since information of multiple clocks is stored on the first network element, when a certain clock fails, other clocks can be used to avoid the situation that the accurate time information cannot be provided externally. In addition, since the information of multiple clocks is stored on the first network element, the second network element can obtain the time information of a clock that best matches the time demand information from the first network element according to its own time demand information, which can realize Provide precise time information.

As a possible implementation method, the second network element receives configuration information of the first clock from the first network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, the One or more of the time keeping capability of the first clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock.

In the third aspect, the embodiment of the present application provides a communication method, which can be performed by a third network element or a module (such as a chip) in the third network element, and the third network element can be a mobility management network element or Network open capability network element. The method includes: the third network element receives the time requirement information from the second network element; the third network element obtains the address information of the first network element according to the time requirement information, and the first network element contains the time requirement information Information about the matched clock; the third network element sends the time requirement information to the first network element according to the address information of the first network element; the third network element receives the first clock from the first network element For time information, the first clock is a clock matching the time requirement information among multiple clocks of the first network element; the third network element sends the time information of the first clock to the second network element.

According to the above scheme, since information of multiple clocks is stored on the first network element, when a certain clock fails, other clocks can be used to avoid the situation that the accurate time information cannot be provided externally. Moreover, since the information of multiple clocks is stored on the first network element, the third network element can obtain the time of a clock that best matches the time requirement information from the first network element based on the time requirement information sent by the second network element information, and provide the time information of the clock to the second network element, so that precise time information can be provided.

As a possible implementation method, the third network element sends a query message to the data management network element, and the query message includes the time requirement information; the third network element receives the first network element from the data management network element address information.

According to the above solution, the third network element obtains the address information of the first network element from the data management network element, so that the address information of the first network element can be obtained accurately and quickly.

As a possible implementation method, the third network element receives configuration information of the first clock from the first network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, the One or more of the time keeping capability of the first clock, the time service objects allowed by the first clock, the service area of the first clock, the clock transfer capability of the first clock, or the quality level of the first clock; The three network elements send the configuration information of the first clock to the second network element.

In a fourth aspect, the embodiment of the present application provides a communication method, and the method may be executed by a data management network element or a module (such as a chip) in the data management network element. The method includes: the data management network element receives a query message from a third network element, the query message includes time requirement information; the data management network element determines a first network element according to the time requirement information, and the first network element includes The information of the clock matching the time requirement information; the data management network element sends the address information of the first network element to the third network element.

As a possible implementation method, the third network element is a mobility management network element or a network capability opening network element.

In a fifth aspect, the embodiment of the present application provides a communication device, and the device may be a first network element or a module (such as a chip) applied to the first network element. The device has the function of realizing any realization method of the first aspect above. This function may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In a sixth aspect, the embodiment of the present application provides a communication device, and the device may be a second network element or a module (such as a chip) applied to the second network element. The device has the function of implementing any implementation method of the second aspect above. This function may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In a seventh aspect, the embodiment of the present application provides a communication device, and the device may be a third network element or a module (such as a chip) applied to the third network element. The device has the function of realizing any realization method of the third aspect above. This function may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In an eighth aspect, the embodiment of the present application provides a communication device, which may be a data management network element or a module (such as a chip) applied to the data management network element. The device has the function of realizing any realization method of the fourth aspect above. This function may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In the ninth aspect, the embodiment of the present application provides a communication device, including a processor and a memory; the memory is used to store computer instructions, and when the device is running, the processor executes the computer instructions stored in the memory, so that the device executes Any implementation method in the first aspect to the fourth aspect above.

In a tenth aspect, the embodiment of the present application provides a communication device, including a unit or means (means) for performing each step of any implementation method in the first aspect to the fourth aspect.

In the eleventh aspect, the embodiment of the present application provides a communication device, including a processor and an interface circuit, the processor is used to communicate with other devices through the interface circuit, and execute any implementation method in the first aspect to the fourth aspect above . The processor includes one or more.

In a twelfth aspect, an embodiment of the present application provides a communication device, including a processor coupled to a memory, and the processor is used to call a program stored in the memory to execute any implementation in the first aspect to the fourth aspect above method. The memory may be located within the device or external to the device. And there may be one or more processors.

In the thirteenth aspect, the embodiment of the present application also provides a computer-readable storage medium, the computer-readable storage medium stores instructions, and when it runs on the communication device, the above-mentioned first aspect to the fourth aspect Any implementation method of is executed.

In the fourteenth aspect, the embodiment of the present application also provides a computer program product, the computer program product includes computer programs or instructions, when the computer program or instructions are run by the communication device, any of the above first to fourth aspects The implementation method is executed.

In a fifteenth aspect, the embodiment of the present application further provides a chip system, including: a processor, configured to execute any implementation method in the first aspect to the fourth aspect above.

In a sixteenth aspect, the embodiment of the present application further provides a communication system, including a first network element configured to execute any implementation method of the first aspect, and a second network element configured to execute any implementation method of the second aspect.

In a seventeenth aspect, the embodiment of the present application further provides a communication system, including a third network element configured to execute any implementation method of the third aspect, and a data management network element configured to execute any implementation method of the fourth aspect.

Description of drawings

Figure 1 is a schematic diagram of a 5G network architecture based on a service architecture;

Figure 2 is a schematic diagram of a 5G network architecture based on a point-to-point interface;

FIG. 3 is a flowchart of a communication method provided in an embodiment of the present application;

FIG. 4 is a flowchart of a communication method provided by an embodiment of the present application;

FIG. 5 is a schematic diagram of a communication device provided in an embodiment of the present application;

FIG. 6 is a schematic diagram of a communication device provided by an embodiment of the present application.

Detailed ways

Figure 1 is a schematic diagram of a 5G network architecture based on a service-based architecture. The 5G network architecture shown in FIG. 1 may include terminal equipment, access network equipment, and core network equipment. The terminal device accesses the data network (data network, DN) through the access network device and the core network device. Among them, the core network equipment includes some or all of the following network elements: unified data management (unified data management, UDM) network elements, unified database (unified data repository, UDR) network elements, network exposure function (network exposure function, NEF) Network element (not shown in the figure), application function (application function, AF) network element, policy control function (policy control function, PCF) network element, access and mobility management function (access and mobility management function, AMF) Network element, session management function (session management function, SMF) network element, user plane function (user plane function, UPF) network element, network storage function (Network Repository Function, NRF) network element (not shown in the figure), clock Network function (timing network function, TNF) network element.

The terminal equipment (also called user equipment, UE) of this application is a device with wireless transceiver function, which can be deployed on land, including indoor or outdoor, handheld or vehicle-mounted; it can also be deployed on water (such as ships, etc.); can also be deployed in the air (such as aircraft, balloons and satellites, etc.). The terminal device may be a mobile phone, a tablet computer (pad), a computer with a wireless transceiver function, a virtual reality (virtual reality, VR) terminal, an augmented reality (augmented reality, AR) terminal, an industrial control (industrial control ), wireless terminals in self driving, wireless terminals in remote medical, wireless terminals in smart grid, wireless terminals in transportation safety , wireless terminals in smart cities, wireless terminals in smart homes, etc.

The above-mentioned terminal device can establish a connection with the operator network through an interface provided by the operator network (such as N1, etc.), and use services such as data and/or voice provided by the operator network. The terminal device can also access the DN through the operator's network, and use the operator's service deployed on the DN, and/or the service provided by a third party. Wherein, the above-mentioned third party may be a service party other than the operator's network and the terminal device, and may provide other services such as data and/or voice for the terminal device. Among them, the specific form of expression of the above-mentioned third party can be determined according to the actual application scenario, and is not limited here.

The access network device is a device that provides wireless communication functions for terminal devices. Access network equipment includes, but is not limited to: a next-generation base station (g nodeB, gNB) in 5G, an evolved node B (evolved node B, eNB), a radio network controller (radio network controller, RNC), a node B ( node B, NB), base station controller (base station controller, BSC), base transceiver station (base transceiver station, BTS), home base station (for example, home evolved nodeB, or home node B, HNB), baseband unit (baseBand unit , BBU), transmission point (transmitting and receiving point, TRP), transmission point (transmitting point, TP), mobile switching center, etc.

Access network equipment and terminal equipment can be fixed or mobile. Access network equipment and terminal equipment can be deployed on land, including indoor or outdoor, handheld or vehicle-mounted; they can also be deployed on water; they can also be deployed on aircraft, balloons and artificial satellites in the air. The embodiments of the present application do not limit the application scenarios of the access network device and the terminal device.

In this application, the mobility management network element is a control plane network element provided by the operator network, which is responsible for access control and mobility management of terminal equipment accessing the operator network, such as including mobility status management, assigning user temporary identities, Functions such as authenticating and authorizing users. In 5G, the mobility management network element can be an AMF network element. In future communications such as the 6th generation (6G), the mobility management network element can still be an AMF network element, or have other names. Applications are not limited.

In this application, the session management network element is a control plane network element provided by an operator network, and is responsible for managing a protocol data unit (protocol data unit, PDU) session of a terminal device. A PDU session is a channel for transmitting PDUs, and terminal equipment needs to transmit PDUs with DN through the PDU session. The PDU session is established, maintained and deleted by the SMF network element. Session management network elements include session management (such as session establishment, modification and release, including tunnel maintenance between user plane network elements and access network equipment), selection and control of user plane network elements, service and session continuity (Service and Session Continuity (SSC) mode selection, roaming and other session-related functions. In 5G, the session management network element can be an SMF network element. In future communications such as 6G, the session management network element can still be an SMF network element, or have other names, which are not limited in this application.

In this application, the user plane network element is a gateway provided by an operator, and is a gateway for communication between the operator's network and the DN. UPF network elements include data packet routing and transmission, packet detection, service usage reporting, Quality of Service (QoS) processing, lawful interception, uplink packet detection, downlink data packet storage, and other user-plane-related functions. In 5G, the user plane network element can be a UPF network element. In future communications such as 6G, the user plane network element can still be a UPF network element, or have other names, which are not limited in this application.

In this application, the data management network element is the control plane network element provided by the operator, which is responsible for storing the subscriber permanent identifier (SUPI), credential, and security context of the subscriber in the operator's network. context), signing data and other information. The information stored by the data management network element can be used for authentication and authorization of terminal equipment to access the operator's network. Wherein, the above-mentioned subscribers of the operator network may specifically be users who use services provided by the operator network, such as users who use China Telecom's mobile phone chip card, or users who use China Mobile's mobile phone chip card. The Subscription Permanent Identifier (SUPI) of the above-mentioned subscriber can be the number of the mobile phone chip card, etc. The credential and security context of the above-mentioned contracted user may be small files stored in the encryption key of the mobile phone chip card or information related to the encryption of the mobile phone chip card for authentication and/or authorization. The aforementioned security context may be data (cookie) or token (token) stored on the user's local terminal (such as a mobile phone). The subscription data of the above-mentioned subscribers can be the supporting services of the mobile phone chip card, such as the data package or network usage of the mobile phone chip card. It should be noted that permanent identifiers, credentials, security contexts, authentication data (cookies), and tokens are equivalent to information related to authentication and authorization. In this application document, for the convenience of description, no distinction or limitation is made. Unless otherwise specified, the embodiment of the present application will be described by taking the security context as an example, but the embodiment of the present application is also applicable to authentication and/or authorization information expressed in other ways. In 5G, the data management network element can be a UDM network element. In future communication such as 6G, the data management network element can still be a UDM network element, or have other names, which are not limited in this application.

In this application, the unified database network element is a control plane network element provided by an operator, and includes the access function for executing contract data, policy data, application data and other types of data. In 5G, the unified database network element can be a UDR network element. In future communications such as 6G, the unified database network element can still be a UDR network element, or have other names, which are not limited in this application.

In this application, the network open network element is a control plane network element provided by an operator. The network opening network element opens the external interface of the operator's network to the third party in a secure manner. When the session management network element needs to communicate with a third-party network element, the network open network element can serve as a relay for the session management network element to communicate with the third-party network element. When the open network element is used as a relay, it can be used as the translation of the identification information of the subscriber and the translation of the identification information of the third-party network element. For example, when the network open network element sends the subscriber's SUPI from the operator's network to a third party, it may translate the SUPI into its corresponding external identity (identity, ID). Conversely, when an open network element sends an external ID (the third-party network element ID) to the operator network, it can translate it into SUPI. In 5G, the network open network element can be a NEF network element. In future communications such as 6G, the network open network element can still be a NEF network element, or have other names, which are not limited in this application.

In this application, the application function network element is used to transfer the requirements from the application side to the network side, for example, QoS requirements or user status event subscription. The application function network element can be a third-party functional entity, or an application server deployed by an operator. In 5G, the application function network element can be an AF network element. In future communications such as 6G, the application function network element can still be an AF network element, or have other names, which are not limited in this application.

In this application, the policy control network element is a control plane function provided by the operator, and is used to provide the policy of the PDU session to the session management network element. Policies may include accounting-related policies, QoS-related policies, and authorization-related policies. In 5G, the policy control network element can be a PCF network element. In future communications such as 6G, the policy control network element can still be a PCF network element, or have other names, which are not limited in this application.

In this application, the network element with the network storage function may be used to provide the network element discovery function, and provide network element information corresponding to the network element type based on the request of other network elements. The network element with the network storage function also provides network element management services, such as network element registration, update, de-registration, and network element status subscription and push. In 5G, the network storage function network element can be an NRF network element. In future communications such as 6G, the network storage function network element can still be an NRF network element, or have other names, which are not limited in this application.

In this application, the clock network function network element can be used to manage the information of one or more clocks in the 5G network, and can provide clock time information externally through its own port, such as directly or indirectly to terminal equipment, access network equipment, core Network devices or third-party application function network elements provide clock time information. Wherein, the time information represents the time, moment or time point of the clock. In 5G, the clock network function network element can be a TNF network element. In future communications such as 6G, the clock network function network element can still be a TNF network element, or have other names, which are not limited in this application.

DN is a network outside the operator's network. The operator's network can access multiple DNs, and various services can be deployed on the DN, which can provide data and/or voice services for terminal equipment. For example, DN is a private network of a smart factory. The sensors installed in the workshop of the smart factory can be terminal devices. The control server of the sensor is deployed in the DN, and the control server can provide services for the sensor. The sensor can communicate with the control server, obtain instructions from the control server, and transmit the collected sensor data to the control server according to the instructions. For another example, DN is a company's internal office network, and the mobile phone or computer of the company's employees can be a terminal device, and the employee's mobile phone or computer can access information and data resources on the company's internal office network.

In Figure 1, Npcf, Nudr, Nudm, Naf, Namf, Nsmf, and Ntnf are the service interfaces provided by the above-mentioned PCF, UDR, UDM, AF, AMF, SMF, and TNF, respectively, and are used to call corresponding service operations. N1, N2, N3, N4, and N6 are interface serial numbers, and the meanings of these interface serial numbers may refer to the description in FIG. 2 .

FIG. 2 is a schematic diagram of a 5G network architecture based on a point-to-point interface. The introduction of the functions of the network elements can refer to the introduction of the functions of the corresponding network elements in FIG. 1 , and will not be repeated here. The main difference between FIG. 2 and FIG. 1 is that: the interface between each control plane network element in FIG. 1 is a service interface, and the interface between each control plane network element in FIG. 2 is a point-to-point interface.

In the architecture shown in Figure 2, the interface names and functions between each network element are as follows:

1), N1: the interface between the AMF and the terminal device, which can be used to transmit NAS signaling (such as including QoS rules from the AMF) to the terminal device.

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

3), N3: the interface between the RAN and the UPF, mainly used to transfer the uplink and downlink user plane data between the RAN and the UPF.

4), N4: The interface between SMF and UPF, which can be used to transfer information between the control plane and the user plane, including controlling the distribution of forwarding rules, QoS control rules, traffic statistics rules, etc. Information reporting.

5), N5: the interface between the AF and the PCF, which can be used for sending application service requests and reporting network events.

6), N6: the interface between UPF and DN, used to transfer the uplink and downlink user data flow between UPF and DN.

7), N7: the interface between PCF and SMF, which can be used to deliver protocol data unit (protocol data unit, PDU) session granularity and service data flow granularity control policy.

8), N8: the interface between AMF and UDM, which can be used for AMF to obtain subscription data and authentication data related to access and mobility management from UDM, and for AMF to register information related to current mobility management of terminal equipment with UDM.

9), N9: a user plane interface between UPF and UPF, used to transmit uplink and downlink user data flows between UPFs.

10), N10: the interface between SMF and UDM, which can be used for SMF to obtain session management-related subscription data from UDM, and for SMF to register current session-related information of terminal equipment with UDM.

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

12), N15: the interface between PCF and AMF, which can be used to issue terminal device policies and access control related policies.

13), N35: the interface between UDM and UDR, which can be used for UDM to obtain user subscription data information from UDR.

14), N36: the interface between PCF and UDR, which can be used for PCF to obtain policy-related subscription data and application data-related information from UDR.

It can be understood that the above-mentioned network element or function may be a network element in a hardware device, or a software function running on dedicated hardware, or a virtualization function instantiated on a platform (for example, a cloud platform). As a possible implementation method, the foregoing network element or function may be implemented by one device, or jointly implemented by multiple devices, or may be a functional module in one device, which is not specifically limited in this embodiment of the present application.

Referring to FIG. 3 , it is a flow chart of a communication method provided by an embodiment of the present application. The method includes the following steps:

Step 301, the second network element sends time requirement information to the first network element. Correspondingly, the first network element receives the time requirement information.

The second network element sends the time requirement information to the first network element for requesting to obtain time information of a clock matching the time requirement information.

In an implementation method, the first network element is a clock network function network element, and of course it can also be other network elements of the core network.

In an implementation method, the second network element is a third-party application function (AF) network element, a terminal device, an access network device or a core network device (such as an AMF network element, an SMF network element, a UPF network element, etc.).

In step 302, the first network element acquires time information of a first clock according to the time requirement information, and the first clock is a clock matching the time requirement information among multiple clocks of the first network element.

As an implementation method, profile information of multiple clocks is stored on the first network element, and the information of each clock stored on the first network element includes one or more of the following information:

1) Clock source (source): indicates the source of the clock, for example, it can be global navigation satellite system (global navigation satellite system, GNSS), clock synchronization network (time synchronization network, TSN) or local clock, etc.

2) Clock accuracy (accuracy): indicates the error between the clock and the main clock, for example, the error may be 1 microsecond (us) or 500 nanoseconds (ns). Wherein, the master clock is a clock of multiple clocks on the first network element.

3) Time holding capability (holdover): Indicates how long the clock can continue to provide accurate time after losing the clock source signal. For example, the clock source of clock 1 is GNSS, and the time holding capability is 24 hours, indicating that when clock 1 loses the GNSS signal, It can still provide accurate time within 24 hours by itself.

4) Allowable timing objects: refer to objects that provide time, such as timing for specific AF or devices in the 5G system.

5) Service area: refers to the service range of the clock, such as delineating the service area at the granularity of the public land mobile network (PLMN), or delineating the service area at the granularity of the tracking area (TA) list .

6) Quality level (clockclass): Output quality level 6 when tracking the global positioning system (GPS), output 7 when maintaining and meeting the performance requirements, output 52 when free oscillation.

7) Clock transmission capability: for example, time service through air interface or time service through 1588 protocol.

Wherein, the multiple clocks on the first network element may include multiple clocks from the same clock source, for example, multiple GNSS clocks, or multiple TSN clocks, and so on.

Specifically, according to the received time requirement information, the first network element determines a clock that matches the time requirement information according to the stored profile information of multiple clocks, such as the first clock, and then the first network element obtains the clock of the first clock. time information. Wherein, the time requirement information sent in the above step 301 includes one or more of the following information: clock source, clock accuracy, clock time keeping capability or service area.

The method for the first network element to determine the clock according to the time requirement information may be, for example: obtaining a clock matching all the information in the time requirement information, or obtaining a clock matching part of the information in the time requirement information. Wherein, if the first network element determines that at least two clocks match the time requirement information according to the time requirement information, the first network element may one or more of them), select a clock with the best performance, or randomly select a clock from the at least two clocks. Exemplarily, the time requirement information includes the TSN clock source and the clock accuracy of 1 us. According to the time requirement information, the first network element obtains three clock sources meeting the time requirement information, which are TSN clock source 1, TSN clock source 2 and TSN clock source 3. Then, the first network element may randomly select a clock source from the three TSN clock sources, or the first network element may select a TSN clock source with the highest clock accuracy from the three TSN clock sources, such as TSN clock source 1, The clock accuracy of TSN clock source 2 and TSN clock source 3 are 1us, 0.9us and 0.8us respectively, then the first network element selects TSN clock source 3, or the first network element selects one of the three TSN clock sources to keep the time The TSN clock source with the highest capability, for example, the time keeping capabilities of TSN clock source 1, TSN clock source 2, and TSN clock source 3 are 24 hours, 23 hours, and 22 hours respectively, and the first network element selects TSN clock source 1.

"Match" in this embodiment of the present application may refer to "same" or "the difference is smaller than a preset threshold".

Step 303, the first network element sends the time information of the first clock to the second network element. Correspondingly, the second network element receives the time information of the first clock.

In this embodiment of the present application, the time information of the first clock may be a specific time, for example, it may be the time, time, or time point of the first clock. The implementation method of the time information will be described below with an example. For example, the time information of the first clock is represented by a field in the following format:

ReferenceTime-r16::=SEQUENCE{

refDays - r16INTEGER(0..72999),

refSeconds - r16INTEGER(0..86399),

refMilliSeconds - r16INTEGER(0..999),

refTenNanoSeconds-r16INTEGER(0..9999-9)

}

Among them, the refDays-r16 field is used to indicate "days" in the time information, the refSeconds-r16 field is used to indicate "seconds" in the time information, the refMilliSeconds-r16 field is used to indicate "milliseconds" in the time information, and refTenNanoSeconds-r16 field is used to indicate "nanoseconds" in time information. For example, the values of the four fields are: 10950, 36066, 500, and 10 respectively, and the corresponding time information is: December 26, 2000 at 10:06:6:500 milliseconds and 100 nanoseconds. After receiving the ReferenceTime-r16 information, the second network element can calculate and obtain the time information of the first clock according to the conversion rule: December 26, 2000, 10:00, 6:6, 500 milliseconds, 100 nanoseconds.

As another implementation method, the time information of the first clock may also be relevant information for determining time, for example, it may be the difference between the time of the first clock and the time of the second network element. The element can calibrate the time of the second network element according to the difference value and the time of the second network element, so as to realize clock synchronization of the second network element and the first network element.

According to the above steps 301 to 303, since the information of multiple clocks is stored on the first network element, when a certain clock fails, other clocks can be used to avoid the situation that accurate time information cannot be provided externally. Moreover, since the information of multiple clocks is stored on the first network element, the first network element can provide the second network element with the time of a clock that best matches the time requirement information based on the time requirement information sent by the second network element Information, can provide accurate time information.

As an implementation method, in order to keep the second network element synchronized with the first clock, the first network element can continuously perform the above step 303, for example, the first network element continues to send the second network element to the second network element according to the set period For the time information of a clock, the continuation here means that the latest time information of the first clock is always sent to the second network element according to the set period. The period here refers to a very short time interval, for example, it can be 1ns, 2ns and so on.

As another implementation method, in the above step 301, the second network element also sends the time keeping capability of the second network element to the first network element, and the time keeping capability of the second network element indicates that the second network element loses the clock source signal The length of time after which the precise time will continue to be provided. In order to keep the second network element synchronized with the first clock, the first network element can perform the above step 303 according to the time keeping capability of the second network element. For example, if the time keeping capability of the second network element is 24 hours, then the first network element The network element sends the time information of the first clock to the second network element every 24 hours.

As an implementation method, after the above step 302, the first network element may also send the configuration information of the first clock to the second network element, and the configuration information includes the clock source of the first clock, the clock precision of the first clock, the second One or more of the time keeping capability of a clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock. After receiving the configuration information of the first clock, the second network element can judge whether to maintain the content of the time requirement information (ie, the time requirement information in step 301) or update the content of the time requirement information according to the configuration information. For example, after receiving the configuration information of the first clock, the second network element determines that the configuration information of the first clock completely matches the time requirement information sent in step 301, and the second network element decides to accept the time of the first clock. information, and maintaining that time demand information. For another example, after receiving the configuration information of the first clock, the second network element determines that the configuration information of the first clock does not completely match the time requirement information sent in the above step 301, then the second network element decides to accept the configuration information according to the local policy. The time information of the first clock and maintain the time requirement information, or reject the time information of the first clock, and resend the time requirement information or update the time requirement information and then send the updated time requirement information.

Referring to FIG. 4 , it is a flow chart of a communication method provided by an embodiment of the present application. The method includes the following steps:

Step 401, the second network element sends time requirement information to the third network element. Correspondingly, the third network element receives the time requirement information.

The second network element sends the time requirement information to the third network element, for requesting to obtain time information of a clock matching the time requirement information. The time requirement information includes one or more of the following information: clock source, clock accuracy, clock time keeping capability or service area.

In one implementation method, the second network element is a third-party application function (AF) network element, and the third network element is a network capability opening network element. The network capability opening network element may be a NEF network element or a future communication system with Other network elements that perform the functions of the NEF network element.

In one implementation method, the second network element is a terminal device, an access network device, or a core network device (such as an SMF network element, a UPF network element, etc.), and a third network element is a mobility management network element. The management network element may be an AMF network element or other network elements having the function of the AMF network element in the future communication system.

In step 402, the third network element acquires address information of the first network element according to the time requirement information, and the first network element includes clock information matching the time requirement information.

As an implementation method, the third network element may locally obtain the first network element matching the time requirement information according to the time requirement information, and then obtain the address information of the first network element. The first network element contains clock information matching the time requirement information.

As another implementation method, the third network element may send a query message to a data management network element (such as NRF, UDM, or UDR), where the query message includes time requirement information. The query message requests to query the address information of the network element that can provide the time requirement information, and the network element can provide the time information of the clock that matches the time requirement information. The data management network element determines the first network element that matches the time requirement information according to the time requirement information, and the first network element includes clock information that matches the time requirement information. Then the data management network element sends the address information of the first network element to the third network element. For example, address information of multiple first network elements and configuration information of each clock managed by each first network element are stored in the data management network element. The configuration information of each clock includes clock source, clock precision, One or more of the time keeping capability of the clock, the time service objects allowed by the clock, the service area of the clock, the transfer capability of the clock, or the quality level of the clock. After receiving the time requirement information, the data management network element may obtain a clock matching the time requirement information, and then obtain address information of the first network element that manages the clock.

Step 403, the third network element sends time requirement information to the first network element according to the address information of the first network element. Correspondingly, the first network element receives the time requirement information.

The third network element sends time requirement information to the first network element, for requesting to obtain time information of a clock matching the time requirement information.

Step 404, the first network element obtains time information of a first clock according to the time requirement information, and the first clock is a clock matching the time requirement information among multiple clocks of the first network element.

This step is the same as the above-mentioned step 302, and reference may be made to the foregoing description.

Step 405, the first network element sends the time information of the first clock to the third network element. Correspondingly, the third network element receives the time information of the first clock.

Step 406, the third network element sends the time information of the first clock to the second network element. Correspondingly, the second network element receives the time information of the first clock.

According to the above steps 401 to 406, since the information of multiple clocks is stored on the first network element, when a certain clock fails, other clocks can be used to avoid the situation that the accurate time information cannot be provided externally. Moreover, since the information of multiple clocks is stored on the first network element, the third network element can obtain the time of a clock that best matches the time requirement information from the first network element based on the time requirement information sent by the second network element information, and provide the time information of the clock to the second network element, so that precise time information can be provided.

As an implementation method, in order to keep the second network element synchronized with the first clock, the above steps 405 to 406 can be continuously performed. For example, the first network element continues to send the first The time information of the clock, and then the third network element continuously sends the time information of the first clock to the second network element. The period here refers to a very short time interval, for example, it can be 1ns, 2ns and so on.

As another implementation method, in the above step 401, the second network element also sends the time keeping capability of the second network element to the third network element, and in the above step 403, the third network element also sends the second network element to the first network element The time keeping capability of the second network element, the time keeping capability of the second network element indicates the time period for which the second network element continues to provide accurate time after losing the clock source signal. In order to keep the second network element synchronized with the first clock, the first network element can perform the above step 405 according to the time keeping capability of the second network element, then the third network element receives the first clock from the first network element After receiving the time information, forward it to the second network element. For example, the time keeping capability of the second network element is 24 hours, then the first network element sends the time information of the first clock to the third network element every 24 hours, and then the third network element sends the time information of the first clock to the The second network element.

As an implementation method, after the above step 402, the first network element may also send the configuration information of the first clock to the third network element, and the configuration information includes the clock source of the first clock, the clock accuracy of the first clock, the second One or more of the time keeping capability of a clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transfer capability of the first clock, or the quality level of the first clock, and then the third network element sends The second network element sends configuration information of the first clock. After receiving the configuration information of the first clock, the second network element can judge whether to maintain the content of the time requirement information (ie, the time requirement information in step 401) or update the content of the time requirement information according to the configuration information. For example, after receiving the configuration information of the first clock, the second network element determines that the configuration information of the first clock completely matches the time requirement information sent in step 301, and the second network element decides to accept the time of the first clock. information, and maintaining that time demand information. For another example, after receiving the configuration information of the first clock, the second network element determines that the configuration information of the first clock does not completely match the time requirement information sent in the above step 301, then the second network element decides to accept the configuration information according to the local policy. The time information of the first clock and maintain the time requirement information, or reject the time information of the first clock and resend the time requirement information or update the time requirement information and send updated time requirement information.

The relationship between the embodiment corresponding to Figure 4 and the embodiment corresponding to Figure 3 above is: the embodiment corresponding to Figure 4 and the embodiment corresponding to Figure 3 above are both initiated by the second network element and corresponding to the time requirement information The time information of the clock, and the first network element provides the time information of the clock corresponding to the time demand information, but the difference is that in the embodiment corresponding to Figure 3, the second network element directly interacts with the first network element, For example, refer to the above step 301 and step 303. In the embodiment corresponding to FIG. . The descriptions of similar steps in the two embodiments can refer to each other.

It can be understood that, in order to realize the functions in the foregoing embodiments, the first network element, the second network element, the third network element and the data management network element include corresponding hardware structures and/or software modules for performing respective functions. Those skilled in the art should easily realize that the present application can be implemented in the form of hardware or a combination of hardware and computer software with reference to the units and method steps of the examples described in the embodiments disclosed in the present application. Whether a certain function is executed by hardware or computer software drives the hardware depends on the specific application scenario and design constraints of the technical solution.

FIG. 5 and FIG. 6 are schematic structural diagrams of possible communication devices provided by the embodiments of the present application. These communication devices can be used to implement the functions of the first network element, the second network element, the third network element or the data management network element in the above method embodiments, and thus can also realize the beneficial effects of the above method embodiments. In the embodiment of this application, the communication device may be the first network element, the second network element, the third network element or the data management network element, or it may be a module (such as a chip) applied to the first network element, a second A network element module (such as a chip), a third network element module (such as a chip), or a module (such as a chip) of a data management network element.

As shown in FIG. 5 , a communication device 500 includes a processing unit 510 and a transceiver unit 520 . The communication device 500 is configured to implement functions of the first network element, the second network element, the third network element, or the data management network element in the foregoing method embodiments.

When the communication device 500 is used to realize the function of the first network element in the above method embodiment, the transceiver unit 520 is used to receive the time requirement information from the second network element; the processing unit 510 is used to, according to the time requirement information, Obtain time information of a first clock, where the first clock is a clock that matches the time requirement information among multiple clocks of the first network element; the transceiver unit 520 is configured to send the time of the first clock to the second network element information.

As a possible implementation method, the transceiver unit 520 is configured to continuously send the time information of the first clock to the second network element according to a set period.

As a possible implementation method, the transceiver unit 520 is further configured to receive the time keeping capability of the second network element from the second network element, and the time keeping capability of the second network element indicates that the second network element loses the clock source signal Continue to provide the precise time for a duration; the processing unit 510 is configured to send the time information of the first clock to the second network element through the transceiver unit 520 according to the time keeping capability of the second network element.

As a possible implementation method, the processing unit 510 is configured to acquire time information of at least two clocks among the plurality of clocks according to the time requirement information, and the at least two clocks both match the time requirement information; from the at least The first clock is selected among the two clocks.

As a possible implementation method, the transceiver unit 520 is configured to send configuration information of the first clock to the second network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, the One or more of the time keeping capability of the first clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock.

When the communication device 500 is used to implement the function of the second network element in the above method embodiment, the transceiver unit 520 is used to send time requirement information to the first network element; and receive the first clock from the first network element time information, the first clock is a clock matching the time requirement information among the multiple clocks of the first network element.

As a possible implementation method, the transceiver unit 520 is configured to receive configuration information of the first clock from the first network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, One or more of the time keeping capability of the first clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock.

When the communication device 500 is used to realize the function of the third network element in the above method embodiment, the transceiver unit 520 is used to receive the time requirement information from the second network element; the processing unit 510 is used to, according to the time requirement information, Obtaining address information of a first network element, the first network element including clock information matching the time requirement information; and sending the time to the first network element through the transceiver unit 520 according to the address information of the first network element Demand information; the transceiver unit 520 is configured to receive time information from a first clock of the first network element, where the first clock is a clock matching the time demand information among multiple clocks of the first network element; The second network element sends the time information of the first clock.

As a possible implementation method, the transceiver unit 520 is configured to send a query message to the data management network element, where the query message includes the time requirement information; and receive address information of the first network element from the data management network element.

As a possible implementation method, the transceiver unit 520 is configured to receive configuration information of the first clock from the first network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, One or more of the time keeping capability of the first clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transfer capability of the first clock, or the quality level of the first clock; The third network element sends configuration information of the first clock to the second network element.

When the communication device 500 is used to implement the function of the data management network element in the above method embodiment, the transceiver unit 520 is used to receive a query message from a third network element, the query message includes time requirement information; the processing unit 510, The first network element is configured to determine the first network element according to the time requirement information, and the first network element includes clock information matching the time requirement information; the transceiver unit 520 is configured to send the first network element to the third network element Address information.

More detailed descriptions about the processing unit 510 and the transceiver unit 520 can be directly obtained by referring to relevant descriptions in the above method embodiments, and details are not repeated here.

As shown in FIG. 6 , the communication device 600 includes a processor 610 and an interface circuit 620 . The processor 610 and the interface circuit 620 are coupled to each other. It can be understood that the interface circuit 620 may be a transceiver or an input-output interface. Optionally, the communication device 600 may further include a memory 630 for storing instructions executed by the processor 610 or storing input data required by the processor 610 to execute the instructions or storing data generated by the processor 610 after executing the instructions.

When the communication device 600 is used to implement the above method embodiments, the processor 610 is used to implement the functions of the processing unit 510 , and the interface circuit 620 is used to implement the functions of the transceiver unit 520 .

It can be understood that the processor in the embodiments of the present application may be a central processing unit (central processing unit, CPU), and may also be other general processors, digital signal processors (digital signal processor, DSP), application specific integrated circuits (application specific integrated circuit, ASIC), field programmable gate array (field programmable gate array, FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. A general-purpose processor can be a microprocessor, or any conventional processor.

The method steps in the embodiments of the present application may be implemented by means of hardware, or may be implemented by means of a processor executing software instructions. Software instructions can be composed of corresponding software modules, and software modules can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only Memory, registers, hard disk, removable hard disk, CD-ROM or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be a component of the processor. The processor and storage medium can be located in the ASIC. Certainly, the processor and the storage medium may also exist in the base station or the terminal as discrete components.

In the above embodiments, all or part of them may be implemented by software, hardware, firmware or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product comprises one or more computer programs or instructions. When the computer program or instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are executed in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, a base station, user equipment or other programmable devices. The computer program or instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer program or instructions may be downloaded from a website, computer, A server or data center transmits to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or a data center integrating one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; it may also be an optical medium, such as a digital video disk; and it may also be a semiconductor medium, such as a solid state disk. The computer readable storage medium may be a volatile or a nonvolatile storage medium, or may include both volatile and nonvolatile types of storage media.

In each embodiment of the present application, if there is no special explanation and logical conflict, the terms and/or descriptions between different embodiments are consistent and can be referred to each other, and the technical features in different embodiments are based on their inherent Logical relationships can be combined to form new embodiments.

In this application, "at least one" means one or more, and "multiple" means two or more. "And/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A, B can be singular or plural. In the text description of this application, the character "/" generally indicates that the contextual objects are an "or" relationship; in the formulas of this application, the character "/" indicates that the contextual objects are a "division" Relationship.

It can be understood that the various numbers involved in the embodiments of the present application are only for convenience of description, and are not used to limit the scope of the embodiments of the present application. The size of the serial numbers of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its functions and internal logic.

Claims

A communication method, characterized in that, comprising:

The first network element receives time requirement information from the second network element;

The first network element acquires time information of a first clock according to the time requirement information, and the first clock is a clock matching the time requirement information among multiple clocks of the first network element;

The first network element sends the time information of the first clock to the second network element.
The method according to claim 1, wherein the first network element sends the time information of the first clock to the second network element, comprising:

The first network element continuously sends the time information of the first clock to the second network element according to a set period.
The method of claim 1, further comprising:

the first network element receives the time keeping capability of the second network element from the second network element;

The first network element sending the time information of the first clock to the second network element includes:

The first network element sends the time information of the first clock to the second network element according to the time keeping capability of the second network element.
The method according to any one of claims 1 to 3, wherein the first network element acquires the time information of the first clock according to the time requirement information, including:

The first network element acquires time information of at least two clocks among the plurality of clocks according to the time requirement information, and the at least two clocks both match the time requirement information;

The first network element selects the first clock from the at least two clocks.
The method according to any one of claims 1 to 4, further comprising:

The first network element sends configuration information of the first clock to the second network element, where the configuration information includes the clock source of the first clock, the clock precision of the first clock, the first One or more of the timekeeping capability of the clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transmission capability of the first clock, or the quality level of the first clock.
The method according to any one of claims 1 to 5, wherein the time requirement information includes one or more of the following information:

Clock source, clock accuracy, time keeping capability of clock or service area.
The method according to any one of claims 1 to 6, wherein the second network element is an application function network element, a terminal device, an access network device or a core network device.
A communication method, characterized in that, comprising:

The second network element sends time requirement information to the first network element;

The second network element receives time information from a first clock of the first network element, where the first clock is a clock matching the time requirement information among multiple clocks of the first network element.
The method of claim 8, further comprising:

The second network element receives configuration information of the first clock from the first network element, where the configuration information includes the clock source of the first clock, the clock accuracy of the first clock, the first One or more of the time keeping capability of a clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transfer capability of the first clock, or the quality level of the first clock .
The method according to claim 8 or 9, wherein the time requirement information includes one or more of the following information:

Clock source, clock accuracy, time keeping capability of clock or service area.
The method according to any one of claims 8 to 10, wherein the second network element is an application function network element, a terminal device, an access network device or a core network device.
A communication method, characterized in that, comprising:

The third network element receives the time requirement information from the second network element;

The third network element acquires address information of a first network element according to the time requirement information, and the first network element includes clock information matching the time requirement information;

The third network element sends the time requirement information to the first network element according to the address information of the first network element;

The third network element receives time information from a first clock of the first network element, where the first clock is a clock matching the time requirement information among multiple clocks of the first network element;

The third network element sends the time information of the first clock to the second network element.
The method according to claim 12, wherein the third network element obtains the address information of the first network element according to the time requirement information, comprising:

The third network element sends a query message to the data management network element, and the query message includes the time requirement information;

The third network element receives address information of the first network element from the data management network element.
The method according to claim 12 or 13, further comprising:

The third network element receives configuration information of the first clock from the first network element, where the configuration information includes a clock source of the first clock, a clock accuracy of the first clock, and the first clock One or more of the time keeping capability of a clock, the timing objects allowed by the first clock, the service area of the first clock, the clock transfer capability of the first clock, or the quality level of the first clock ;

The third network element sends configuration information of the first clock to the second network element.
The method according to any one of claims 12 to 14, wherein the time requirement information includes one or more of the following information:

Clock source, clock accuracy, time keeping capability of clock or service area.
The method according to any one of claims 12 to 15, wherein the second network element is an application function network element, a terminal device, an access network device or a core network device.
The method according to any one of claims 12 to 16, wherein the third network element is a mobility management network element or a network capability opening network element.
A communication method, characterized in that, comprising:

The data management network element receives a query message from the third network element, where the query message includes time requirement information;

The data management network element determines a first network element according to the time requirement information, and the first network element includes clock information matching the time requirement information;

The data management network element sends the address information of the first network element to the third network element.
The method according to claim 18, wherein the time requirement information includes one or more of the following information:

Clock source, clock accuracy, time keeping capability of clock or service area.
The method according to claim 18 or 19, wherein the third network element is a mobility management network element or a network capability opening network element.
A communication device, characterized by comprising a module for performing the method according to any one of claims 1 to 7, or a module for performing the method according to any one of claims 8 to 11, or A module for performing a method as claimed in any one of claims 12 to 17, or a module for performing a method as claimed in any one of claims 18 to 20.
A communication device, characterized in that it includes a processor and an interface circuit, the interface circuit is used to receive signals from other communication devices other than the communication device and transmit them to the processor or transfer signals from the processor The signal is sent to other communication devices other than the communication device, and the processor implements the method according to any one of claims 1 to 7 through a logic circuit or executes code instructions, or is used to realize the method according to any one of claims 1 to 7 The method described in any one of claims 8 to 11, or for realizing the method described in any one of claims 12 to 17, or for realizing the method described in any one of claims 18 to 20 .
A communication device, characterized in that it includes a processor and a memory; the memory is used to store computer instructions, and when the device is running, the processor executes the computer instructions stored in the memory, so that the The device executes the method according to any one of claims 1 to 7, or executes the method according to any one of claims 8 to 11, or executes the method according to any one of claims 12 to 17, or executes A method as claimed in any one of claims 18 to 20.
A computer-readable storage medium, characterized in that computer programs or instructions are stored in the storage medium, and when the computer programs or instructions are executed by a communication device, the implementation of any one of claims 1 to 20 Methods.
A communication system, characterized by comprising a first network element for performing the method according to any one of claims 1 to 7, and a network element for performing the method according to any one of claims 8 to 11 The second network element.