CN116889083A - User plane connection establishment method and device and storage medium - Google Patents

Abstract

The disclosure provides a method and a device for establishing user plane connection, and a storage medium, wherein the method comprises the following steps: determining a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function LMF, wherein the first device comprises at least one of a terminal, the AMF, a source LMF, and a session management function SMF; and sending information of the target LMF to the SMF, wherein the information of the target LMF is used for indicating the SMF to establish user plane connection for the terminal and the target LMF. In the method, the reselection of the LMF can be triggered by at least one device in the terminal, the AMF, the source LMF and the SMF, and the influence of the reselection of the LMF on the SMF and the UPF is considered, so that the reliability of the established user plane connection is improved, and the availability is high.

Description

User plane connection establishment method and device and storage medium

Technical Field

The present disclosure relates to the field of communications, and in particular, to a method and apparatus for establishing a user plane connection, and a storage medium.

Background

At present, a user plane connection can be established between a terminal and a location management function (Location Management Function, LMF), the user plane connection is independent of connection between other network elements in a 5th generation mobile communication technology (5th Generation Mobile Communication Technology,5G) system, and a 5G system can have more effective communication load through user plane positioning, a single session can process a plurality of transactions, and a plurality of positioning modes can be supported.

Disclosure of Invention

The embodiment of the disclosure provides a user plane connection establishment method and device and a storage medium.

According to a first aspect of embodiments of the present disclosure, there is provided a user plane connection establishment method, the method being performed by an access and mobility management function AMF, comprising:

determining a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function LMF, wherein the first device comprises at least one of a terminal, the AMF, a source LMF, and a session management function SMF;

and sending the information of the target LMF to an SMF, wherein the information of the target LMF is used for indicating the SMF to establish user plane connection for the terminal and the target LMF.

Optionally, in case the first device comprises a terminal, the determining that the first device triggers reselection of the location management function LMF comprises:

determining, in response to receiving a first message sent by a terminal, that the terminal triggers reselection of the LMF, wherein the first message includes a cause of reestablishing the user plane connection; alternatively, the first message indicates a cause of reestablishing the user plane connection.

Optionally, the first message includes any one of the following:

The uplink non-access stratum transmits an UL NAS TRANSPORT message;

a service request message.

Optionally, the first message includes:

and the first user plane information comprises information of the source LMF.

Optionally, in a case where the first device includes an SMF, the determining that the first device triggers reselection of the location management function LMF includes:

and in response to receiving a second message sent by the SMF, determining that the SMF triggers reselection of the LMF, wherein the second message is used for indicating a PDU session related change.

Optionally, the method further comprises:

and subscribing to a PDU session management context state reminding service of the SMF before receiving the second message sent by the SMF.

Optionally, in the case that the first device includes an AMF, the determining that the first device triggers reselection of the location management function LMF includes any one of:

in response to determining that the state of the terminal changes, determining that the AMF triggers reselection of the LMF;

determining that the AMF triggers reselection of the LMF based on a third message sent by the SMF, the third message including information of a user plane function UPF and/or information related to the LMF;

And determining that the AMF triggers reselection of the LMF based on a fourth message sent by the terminal, wherein the fourth message comprises the terminal mobility information.

Optionally, the method further comprises:

and sending a fifth message to the SMF, wherein the fifth message is used for determining whether to execute UPF relocation by the SMF.

Optionally, the fifth message includes:

PDU session update request message.

Optionally, when the SMF subscribes to a state notification of the LMF, the fifth message includes:

a notification message for notifying the SMF of a state change of the LMF.

Optionally, the fifth message is used to notify the SMF of at least one of:

the LMF connected with the user plane of the terminal is changed;

information of the target LMF.

Optionally, the information of the target LMF includes at least one of:

an internet protocol, IP, address of the target LMF;

a fully qualified domain name, FQDN, of the target LMF;

identification of the target LMF;

service area of the target LMF.

Optionally, the method further comprises:

based on the information of the target LMF, an insertion or relocation process of an intermediate session management function I-SMF is triggered.

Optionally, the method further comprises:

And receiving a response message sent by the SMF after repositioning the UPF.

Optionally, the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

According to a second aspect of embodiments of the present disclosure, there is provided a user plane connection establishment method, the method being performed by a session management function SMF, comprising:

receiving information of a target Location Management Function (LMF) sent by an access and mobility management function (AMF), wherein the information of the target LMF is at least one of a terminal, the AMF, a source LMF and a Session Management Function (SMF) after the AMF determines that first equipment triggers reselection of the LMF and determines the target LMF;

and establishing user plane connection for the terminal and the target LMF based on the information of the target LMF.

Optionally, the method further comprises:

in response to determining that a reselection of the location management function, LMF, needs to be triggered, a second message is sent to the AMF, the second message indicating a PDU session related change.

Optionally, the method further comprises:

determining that the AMF subscribes to a PDU session management context state alert service of the SMF.

Optionally, the method further comprises:

receiving a fifth message sent by the AMF;

based on the fifth message, it is determined whether a UPF relocation needs to be performed.

Optionally, the fifth message includes:

PDU session update request message.

Optionally, when the SMF subscribes to a state notification of the LMF, the fifth message includes:

a notification message for notifying the SMF of a state change of the LMF.

Optionally, the fifth message is used to notify the SMF of at least one of:

the LMF connected with the user plane of the terminal is changed;

information of the target LMF.

Optionally, the information of the target LMF includes at least one of:

an internet protocol, IP, address of the target LMF;

a fully qualified domain name, FQDN, of the target LMF;

identification of the target LMF;

service area of the target LMF.

Optionally, the method further comprises:

responsive to determining that a UPF relocation is required to be performed, determining a relocated UPF;

and sending a response message to the AMF.

Optionally, the establishing a user plane connection for the terminal and the target LMF based on the information of the target LMF includes:

and establishing the user plane connection for the terminal and the target LMF through the relocated UPF based on the information of the target LMF.

Optionally, the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

According to a third aspect of embodiments of the present disclosure, there is provided a method for establishing a user plane connection, the method being performed by a terminal and comprising:

in response to determining that reselection of a location management function, LMF, needs to be triggered, sending a first message to an access and mobility management function, AMF, wherein the first message includes a cause of reestablishing a user plane connection between the terminal and the LMF; alternatively, the first message indicates a cause of reestablishing the user plane connection.

Optionally, the first message includes any one of the following:

the uplink non-access stratum transmits an UL NAS TRANSPORT message;

a service request message.

Optionally, the first message includes:

and the first user plane information comprises information of the source LMF.

Optionally, the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

According to a fourth aspect of embodiments of the present disclosure, there is provided a user plane connection establishment apparatus, the apparatus being applied to an access and mobility management function AMF, comprising:

A determining module configured to determine a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function, LMF, the first device comprising at least one of a terminal, the AMF, a source LMF, and a session management function, SMF;

and the first sending module is configured to send the information of the target LMF to the SMF, wherein the information of the target LMF is used for indicating the SMF to establish user plane connection with the target LMF for the terminal.

According to a fifth aspect of embodiments of the present disclosure, there is provided a user plane connection establishment apparatus, the apparatus being applied to a session management function SMF, comprising:

a receiving module configured to receive information of a target location management function, LMF, sent by an access and mobility management function, AMF, wherein the information of the target LMF is that the AMF determines that a first device triggers reselection of an LMF and determines the target LMF and sends the information to the AMF, and wherein the first device includes at least one of a terminal, the AMF, a source LMF, and a session management function, SMF;

and the connection establishment module is configured to establish user plane connection for the terminal and the target LMF based on the information of the target LMF.

According to a sixth aspect of the embodiments of the present disclosure, there is provided a user plane connection establishment apparatus, which is applied to a terminal, including:

a second sending module configured to send a first message to an access and mobility management function, AMF, in response to determining that a reselection of a location management function, LMF, needs to be triggered, wherein the first message includes a cause of reestablishing the user plane connection; alternatively, the first message indicates a cause of reestablishing the user plane connection.

According to a seventh aspect of embodiments of the present disclosure, there is provided a computer readable storage medium storing a computer program for executing the user plane connection establishment method of any one of the above.

According to an eighth aspect of the embodiments of the present disclosure, there is provided a user plane connection establishment system, including:

an access and mobility management function AMF, where the AMF is configured to execute the user plane connection establishment method described in any one of the above AMF sides;

a session management function SMF, where the SMF is configured to execute the user plane connection establishment method described in any one of the foregoing SMF sides;

a terminal, configured to execute the user plane connection establishment method described in any one of the above terminal sides;

And the Location Management Function (LMF) is used for establishing user plane connection with the terminal.

According to a ninth aspect of the embodiments of the present disclosure, there is provided a user plane connection establishment apparatus, including:

a processor;

a memory for storing processor-executable instructions;

wherein the processor is configured to perform the user plane connection establishment method of any of the above.

The technical scheme provided by the embodiment of the disclosure can comprise the following beneficial effects:

in the method, the reselection of the LMF can be triggered by at least one device in the terminal, the AMF, the source LMF and the SMF, and the influence of the reselection of the LMF on the SMF and the UPF is considered, so that the reliability of the established user plane connection is improved, and the availability is high.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a flow chart illustrating a method for establishing a user plane connection according to an exemplary embodiment.

Fig. 2 is a flow chart illustrating another method of user plane connection establishment in accordance with an exemplary embodiment.

Fig. 3 is a flow chart illustrating another method of user plane connection establishment in accordance with an exemplary embodiment.

Fig. 4 is a flow chart illustrating another method of user plane connection establishment in accordance with an exemplary embodiment.

Fig. 5 is a flow chart illustrating another method of user plane connection establishment in accordance with an exemplary embodiment.

Fig. 6 is a flow chart illustrating another user plane connection establishment method according to an exemplary embodiment.

Fig. 7 is a flow chart illustrating another method of user plane connection establishment in accordance with an exemplary embodiment.

Fig. 8 is a block diagram illustrating a user plane connection establishment apparatus in accordance with an exemplary embodiment.

Fig. 9 is a block diagram of another user plane connection establishment apparatus, shown in accordance with an exemplary embodiment.

Fig. 10 is a block diagram of another user plane connection establishment apparatus, shown in accordance with an exemplary embodiment.

Fig. 11 is a block diagram of a user plane connection establishment system, shown in accordance with an exemplary embodiment.

Fig. 12 is a schematic structural diagram of a user plane connection establishment apparatus according to an exemplary embodiment of the present disclosure.

Fig. 13 is a schematic structural diagram of another user plane connection establishment apparatus according to an exemplary embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the invention. Rather, they are merely examples of apparatus and methods consistent with aspects of the invention as detailed in the accompanying claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of at least one of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, a first message may also be referred to as a second message, and similarly, a second message may also be referred to as a first message, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at … …" or "at … …" or "responsive to a determination", depending on the context.

An embodiment of the present disclosure provides a method for establishing a user plane connection, referring to fig. 1, fig. 1 is a flowchart of a method for establishing a user plane connection, where the method may include the following steps:

in step 101, the source LMF determines that reselection of the LMF is required, and the source LMF transmits a user plane notification (nlmf_location_upnotify) message including user plane information and indicating a modification reason.

Wherein the address of the access and mobility management function (Access and Mobility Management Function, AMF) is provided to the source LMF as a destination address of the notification in a user plane configuration (nlmf_location_upconfig) message or a user plane notification (nlmf_location_upconfield) message.

In step 102, the AMF needs to reselect the target LMF for user plane location.

Wherein the LMF needs to be able to establish a user plane connection for positioning with the terminal. Furthermore, upon relocation of the AMF, i.e., a change in the AMF occurs, the relocated target AMF needs to notify the LMF of the change in the AMF in order for the LMF to determine the changed target AMF.

In step 103, the user plane connection is moved towards the target LMF.

If an AMF reassignment has occurred, step 103 is skipped. Otherwise, steps 103 to 108 are performed between the AMF, the terminal and the target LMF, and the terminal also needs to terminate the connection with the source LMF.

The above steps 101, 102 and 103 are optional execution steps.

In step 104, the AMF sends a nlmf_location_upconfig request message to the source LMF.

The nlmf_location_upconfig message may include a request for the source LMF to terminate a particular user plane connection to the terminal and the target LMF. Alternatively, the nlmf_location_upconfig message may include information about AMF reassignment.

In step 105, if there is a periodic and triggered terminal Location event reporting context, the source LMF may invoke a Location context transfer request (nlmf_location_ LocationContextTransfer Request) service operation to the target LMF to provide the current Location context of the UE.

In step 106, the target LMF notifies the source LMF of the location context transfer service operation result.

In step 107, if the user plane connection between the terminal and the source LMF is still active, the source LMF terminates the connection to the terminal.

In step 108, the LMF sends an nlmf_location_upconfig response message to the AMF to confirm the connection termination or confirm the change of the AMF.

In the above embodiment, the source LMF may trigger the reselection of the LMF, so that a new user plane connection is established between the terminal and the target LMF, which has high availability.

However, in the above-described embodiment, there are the following problems:

the possible trigger for problem one, LMF reselection, is lost.

That is, in the above embodiment, the reselection of the LMF is triggered only by the source LMF, but in practical application, other network elements or terminals may trigger the reselection of the LMF, so in the above embodiment, the case of the reselection of the LMF by the network element other than the source LMF is not considered.

Problem two, lack of consideration of the possible impact of session management functions (Session Management Function, SMF) and user plane functions (User Plane Function, UPF).

The LMF performs user plane connection with the UE through the UPF selected by the SMF. The UPF associated with the LMF may also be affected if the LMF changes, and the possible effects on the SMF and UPF are not considered in the above embodiments.

Therefore, the present disclosure further provides a method and apparatus for establishing a user plane connection, and a storage medium, where reselection of an LMF may be triggered by at least one device selected from a terminal, an AMF, a source LMF, and an SMF, and the influence of the reselection of the LMF on the SMF and the UPF may be considered, so that reliability of the established user plane connection is improved, and availability is high.

The user plane connection establishment method provided by the present disclosure is first introduced from the AMF side.

An embodiment of the present disclosure provides a method for establishing a user plane connection, referring to fig. 2, fig. 2 is a flowchart of a method for establishing a user plane connection, which may be performed by an AMF, and the method may include the following steps:

in step 201, a target LMF for user plane location is determined in response to determining that the first device triggered reselection of the location management function LMF.

It should be noted that, the precondition of the connection establishment method provided by the embodiment of the present disclosure is that the terminal has successfully established the user plane connection with the source LMF. The source LMF refers to an LMF that provides location services for the terminal prior to LMF reselection, and it should be understood that after LMF reselection, the LMF that serves the terminal is switched from the source LMF to the target LMF.

In an embodiment of the present disclosure, the first device includes, but is not limited to, at least one of: terminal, the AMF, source LMF and SMF.

In one possible implementation, the first device may be a source LMF, and when the source LMF finds that the LMF needs to be changed or the user plane connection between the UE and the LMF is re-established, the source LMF sends an nlmf_location_upnotify message including user plane information and indicating a modification reason to the AMF. At this point the AMF determines that the source LMF triggered the reselection of the LMF.

In another possible implementation, the first device may be a terminal, and the AMF determines that the terminal triggers reselection of the LMF if it receives a first message sent by the terminal.

In one example, the first message may include or indicate a reason for reestablishing the user plane connection.

Illustratively, the cause may be terminal mobility or other reasons, which the present disclosure does not limit.

Illustratively, the first message includes the cause, e.g., the first message includes terminal mobility.

For example, the reason may be indicated in the first message, e.g. an information field is set in the first message, and different reasons may be indicated according to the value of the information field, in a possible embodiment, when the bit value of the information field is set to 1, this is used to indicate that the reason is terminal mobility. It should be understood that other bit values and their corresponding reasons are also possible.

In one example, the first message may include first user plane information including information of the source LMF. The information of the source LMF includes, but is not limited to, at least one of: an internet protocol (Internet Protocol, IP) address of the source LMF, a fully qualified domain name (Fully Qualified Domain Name, FQDN) of the source LMF, an identity of the source LMF (e.g., a physical address of the source LMF, etc.), a service area of the source LMF, etc.

In one example, the first message may include, but is not limited to, employing an uplink non-access stratum TRANSPORT (UL NAS TRANSPORT) message, or the first message may employ a SERVICE REQUEST (SERVICE REQUEST) message, which is not limited by the present disclosure.

In another possible implementation, the first device may be an SMF, and the AMF determines that the SMF triggers a reselection of the LMF if it receives a second message sent by the SMF. Wherein the second message may be used to indicate a protocol data unit (Protocol Data Unit, PDU) session related change.

In one example, the second message may be used to indicate a UPF change in connection with the source LMF.

In one example, the AMF may subscribe to a PDU session management context state notification (nsmf_pduse_smcontextstatus) service of the SMF before receiving the second message.

Of course, the AMF may not subscribe to the nsmf_pduse_smcontextstatusnotify service, which is not limited in this disclosure.

In another possible implementation, the first device may be the AMF itself, i.e. the AMF may trigger the reselection of the LMF itself.

In one example, in response to determining that the state of the terminal changes, it is determined that the AMF triggered reselection of the LMF.

In the embodiment of the disclosure, relevant information of a terminal movement track may be recorded in advance on the AMF, and the AMF may determine that the terminal state changes or the terminal moves based on the information, and may determine to trigger reselection of the LMF.

In another example, the AMF may determine to trigger a reselection of the LMF based on a third message sent by the SMF.

Illustratively, the third message may include, but is not limited to, information of the UPF and/or information related to the LMF, and the AMF determines to trigger reselection of the LMF based on the information of the UPF and/or information related to the LMF in the third message.

In another example, the AMF may determine to trigger reselection of the LMF based on a fourth message sent by the terminal.

The fourth message may include terminal mobility information, for example.

In one possible implementation, the reselection of the LMF includes, but is not limited to, releasing a user plane connection between the terminal and the source LMF, and establishing a user plane connection between the terminal and the target LMF.

In the embodiment of the present disclosure, the AMF may determine, for the terminal, the target LMF based on information such as a serving cell in which the terminal is located, a terminal location, and the like, when it is determined that the first device triggers reselection of the LMF. The target LMF is an LMF determined to provide location services for the terminal after the LMF reselection by the AMF.

In step 202, information of the target LMF is sent to an SMF, where the information of the target LMF is used to instruct the SMF to establish a user plane connection with the target LMF for the terminal.

Illustratively, the information of the target LMF includes, but is not limited to, at least one of: the IP address of the target LMF; FQDN of the target LMF; identification of the target LMF; service areas of the target LMF, etc.

The identification of the target LMF may be information that may uniquely identify the target LMF, such as a physical address of the target LMF, which is not limited in this disclosure.

In the disclosed embodiment, the PDU session has been established when the terminal establishes a user plane connection with the source LMF. In the disclosure, after determining the target LMF, the AMF may send information of the target LMF to the SMF, so that the SMF establishes a user plane connection for the terminal and the target LMF based on the information of the target LMF.

In the disclosed embodiment, for the SMF, if a PSA UPF relocation is triggered based on session and traffic continuity (Session and Service Continuity, SSC) mode 2 or mode 3, the SMF establishes a user plane connection for the terminal with the target LMF through the relocated UPF.

If the SMF determines that the UPF relocation is not performed, the SMF establishes a user plane connection for the terminal to pass through the UPF before the terminal passes through the target LMF.

Wherein SSC mode 2 and mode 3 may include releasing a user plane connection between the terminal and the source LMF and establishing a new user plane connection between the terminal and the target LMF. In the present disclosure, the order of releasing the user plane connection between the terminal and the source LMF and establishing a new user plane connection between the terminal and the target LMF is not limited, and accordingly, the scheme of the present disclosure supports SSC mode 2 and mode 3.

In the embodiment, at least one device of the terminal, the AMF, the source LMF and the SMF may trigger the reselection of the LMF, which expands the trigger factors that may trigger the reselection of the LMF, and has high availability.

In some alternative embodiments, referring to fig. 3, fig. 3 is a flowchart illustrating a method for establishing a user plane connection according to an embodiment, which may be performed by an AMF, the method may include the steps of:

in step 301, a target LMF for user plane location is determined in response to determining that the first device triggered reselection of the location management function LMF.

In an embodiment of the present disclosure, the first device includes, but is not limited to, at least one of: terminal, the AMF, source LMF and SMF.

The implementation of step 301 is similar to that of step 201 described above, and will not be described again here.

In step 302, a fifth message is sent to the SMF, the fifth message being used by the SMF to determine whether to perform a UPF relocation.

In an embodiment of the present disclosure, the fifth message may be a PDU session Update session management context request (nsmf_pduse_update_ SMContext Request) message.

Alternatively, when the SMF subscribes to a state notification of the LMF on the AMF, the fifth message may be a notification message for notifying the SMF of a state change of the LMF. The notification message may be an AMF state change notification (Namf Communication amfstatuschangenotification) message, for example.

For example, before sending the notification message, the AMF may send an AMF state change subscription request (namf_communication_amfstatus change subscription) message to the SMF, and in case the SMF agrees to subscribe, the AMF may receive an AMF state change subscription response (namf_communication_amfstatus change subscription) message sent by the SMF, and accordingly, after determining the target LMF, the AMF may send a namf_communication_amfstatus change notification message to the SMF to determine whether or not to perform the UPF relocation. The Namf Communication amfstatuschangenotifyinfo message includes information of the target LMF, that is, the information of the target LMF is added as a new parameter to the Namf Communication amfstatuschangenotifyinfo message.

In one example, the fifth message may be used to notify the SMF of at least one of: the LMF connected with the user plane of the terminal is changed; information of the target LMF.

Wherein the information of the target LMF includes, but is not limited to, at least one of an IP address of the target LMF, an FQDN of the target LMF, an identification of the target LMF, and a service area of the target LMF.

In one example, the AMF may also trigger an insert or relocation procedure of the intermediate session management function (Intermediate Session Management Function, I-SMF) based on the information of the target LMF.

It should be noted that, after the SMF receives the fifth message, it may determine that any one of the following cases exists:

case one, with a change in SMF, possibly a change in UPF;

the SMF is unchanged in the second case, and the UPF is changed;

the case three, SMF and UPF are all unchanged.

In step 303, a response message sent after the SMF relocates the UPF is received.

In the disclosed embodiment, step 303 is an optional execution step, i.e., the AMF receives the response message only if the SMF determines to execute a relocation to the UPF.

In one example, the response message may be a PDU session Update management context response (nsmf_pdustion_update_ SMContext Response) message.

In embodiments of the present disclosure, the number of UPFs after SMF relocation may be multiple, including but not limited to at least one of: branch Point (Branching Point), upstream classifier (Uplink Classifier, UL CL), PDU session anchor user plane function (PDU Session Anchor User Plane Function, PSA UPF).

In step 304, information of the target LMF is sent to the SMF, where the information of the target LMF is used to instruct the SMF to establish a user plane connection with the target LMF for the terminal.

The implementation of step 304 is similar to that of step 202 described above and will not be described again.

In the above embodiment, the influence of the reselection of the LMF on the SMF and UPF is considered, so that the reliability of the established user plane connection is improved, and the availability is high.

The method for establishing the user plane connection provided by the present disclosure is described below from the SMF side.

An embodiment of the present disclosure provides a method for establishing a user plane connection, referring to fig. 4, fig. 4 is a flowchart of a method for establishing a user plane connection, which may be performed by an SMF, and the method may include the following steps:

in step 401, information of a target location management function LMF transmitted by an access and mobility management function AMF is received.

In the embodiment of the disclosure, the information of the target LMF is sent to the SMF after the AMF determines that the first device triggers reselection of the LMF and determines the target LMF. Wherein the first device includes at least one of a terminal, the AMF, a source LMF, and an SMF.

Here, it should be noted that the reselection of the LMF may be triggered by the SMF. Specifically, the SMF sends a second message to the AMF indicating a PDU session related change in response to determining that a reselection of the location management function LMF needs to be triggered.

In one example, the second message may be used to indicate a UPF change in connection with the source LMF.

In one example, the AMF may subscribe to a PDU session management context state notification (nsmf_pduse_smcontextstatus) service of the SMF before receiving the second message. The nsmf_pduse_smcontextstatus notify message may include information related to the target LMF.

Of course, the AMF may not subscribe to the nsmf_pduse_smcontextstatusnotify service, which is not limited in this disclosure.

In one possible implementation, the information of the target LMF includes, but is not limited to, at least one of: an internet protocol, IP, address of the target LMF; a fully qualified domain name, FQDN, of the target LMF; identification of the target LMF; service area of the target LMF.

In step 402, a user plane connection is established for a terminal and the target LMF based on the information of the target LMF.

In the embodiment of the disclosure, the AMF may establish a user plane connection between the terminal and the target LMF based on information of the target LMF.

In the above embodiment, the SMF may be used as a factor for triggering the reselection of the LMF, which expands the trigger factors that may trigger the reselection of the LMF, and the availability is high.

In some alternative embodiments, referring to fig. 5, fig. 5 is a flowchart illustrating a method for establishing a user plane connection, which may be performed by an SMF, according to an embodiment, the method may include the steps of:

in step 501, information of a target location management function LMF transmitted by an access and mobility management function AMF is received.

The implementation of step 501 is similar to that of step 401 described above, and will not be described in detail here.

In step 502, a fifth message sent by the AMF is received.

In one possible implementation, the fifth message includes a PDU session Update session management context request (nsmf_pdustion_update_ SMContext request) message.

In another possible implementation, when the SMF subscribes to the state notification of the LMF, the fifth message may include a notification message including information of the target LMF for notifying the SMF of the state change of the LMF.

The notification message may be an AMF state change notification (Namf Communication amfstatuschangenotification) message, for example.

Illustratively, before receiving the notification message, the SMF may receive an AMF state change subscription request (namf_communication_amfstatuttusefsubscribe) message sent by the AMF, and in case the SMF agrees to subscribe, the SMF sends an AMF state change subscription response (namf_communication_amfstattusechangesubscribe) message to the AMF, and accordingly, after determining the target LMF, the SMF may receive the namf_communication_amfstattusenotify message sent by the AMF, so that the SMF determines whether or not to perform the UPF relocation. The namf_communication_amfstatus change notification message may include information of the target LMF.

In one example, the fifth message may be used to notify the SMF of at least one of: the LMF connected with the user plane of the terminal is changed; information of the target LMF.

Wherein the information of the target LMF includes, but is not limited to, at least one of an IP address of the target LMF, an FQDN of the target LMF, an identification of the target LMF, and a service area of the target LMF.

In step 503, it is determined whether a UPF relocation needs to be performed based on the fifth message.

After the SMF receives the fifth message, it may be determined that any of the following cases exist:

case one, with a change in SMF, possibly a change in UPF;

the SMF is unchanged in the second case, and the UPF is changed;

the case three, SMF and UPF are all unchanged.

In step 504, in response to determining that a UPF relocation needs to be performed, a relocated UPF is determined.

Step 504 and subsequent step 505 are optional execution steps, and the SMF may determine the relocated UPF in the case that it is determined that the relocation of the UPF needs to be executed.

In an embodiment of the present disclosure, the number of UPFs after relocation may be multiple, including but not limited to at least one of: branch Point (Branching Point), upstream classifier ((Uplink Classifier, UL CL), PDU session anchor user plane function (PDU Session Anchor User Plane Function, PSA UPF).

In step 505, a response message is sent to the AMF.

The response message is used to inform the AMF that the SMF performed the UPF relocation.

In one example, the response message may be a PDU session Update session management context response (nsmf_pdustion_update_ SMContext Response) message.

In step 506, a user plane connection is established between the terminal and the target LMF based on the information of the target LMF sent by the AMF.

In one possible implementation, when the SMF performs a UPF relocation, the SMF establishes a user plane connection with the target LMF for the terminal through the relocated UPF.

In another possible implementation, if the SMF does not perform a UPF relocation, the SMF establishes a user plane connection for the terminal with the target LMF through the previous UPF.

In an embodiment of the present disclosure, the reselection of the LMF includes: releasing the user plane connection between the terminal and the source LMF; and establishing a user plane connection between the terminal and the target LMF.

For SMF, if PSA UPF relocation is triggered based on session and traffic continuity (Session and Service Continuity, SSC) mode 2 or mode 3, the SMF establishes a user plane connection for the terminal with the target LMF through the relocated UPF. Wherein SSC mode 2 and mode 3 may include releasing a user plane connection between the terminal and the source LMF and establishing a new user plane connection between the terminal and the target LMF. In the present disclosure, the order of releasing the user plane connection between the terminal and the source LMF and establishing a new user plane connection between the terminal and the target LMF is not limited, and accordingly, the scheme of the present disclosure supports SSC mode 2 and mode 3.

In the above embodiment, the influence of the reselection of the LMF on the SMF and UPF is considered, so that the reliability and the availability of the established user plane connection are improved.

The user plane connection establishment method provided by the present disclosure is introduced from the terminal side.

An embodiment of the present disclosure provides a method for establishing a user plane connection, referring to fig. 6, and fig. 6 is a flowchart of a method for establishing a user plane connection, which may be executed by a terminal, and the method may include the following steps:

in step 601, a first message is sent to an access and mobility management function, AMF, in response to determining that a reselection to the location management function, LMF, needs to be triggered.

In one example, the first message includes a cause of reestablishing a user plane connection between a terminal and the LMF.

In another example, the first message may indicate a reason for reestablishing the user plane connection.

Illustratively, the cause may be terminal mobility or other reasons, which the present disclosure does not limit.

Illustratively, the first message includes the cause, e.g., the first message includes UE mobility.

For example, the reason may be indicated in the first message, e.g. an information field is set in the first message, and different reasons may be indicated according to the value of the information field, in a possible embodiment, when the bit value of the information field is set to 1, this is used to indicate that the reason is terminal mobility. It should be understood that other bit values and their corresponding reasons are also possible.

In one example, the first message may include first user plane information including information of the source LMF. The information of the source LMF includes, but is not limited to, at least one of: the IP address of the source LMF, the FQDN of the source LMF, the identity of the source LMF, the service area of the source LMF, etc.

In one example, the first message may include, but is not limited to, employing an uplink non-access stratum TRANSPORT (UL NAS TRANSPORT) message, or the first message may employ a SERVICE REQUEST (SERVICE REQUEST) message, which is not limited by the present disclosure.

In one example, the reselection of the LMF includes: releasing the user plane connection between the terminal and the source LMF; and establishing a user plane connection between the terminal and the target LMF.

In the above embodiment, the terminal may be used as a factor for triggering the reselection of the LMF, which expands the trigger factors that may trigger the reselection of the LMF, and the availability is high.

The above scheme is further exemplified as follows.

Referring to fig. 7, fig. 7 is a flowchart of a method for establishing a user plane connection according to an embodiment, including the following steps:

in step 700, the terminal successfully establishes a user plane connection with the source LMF.

In step 701a, the source LMF determines that reselection of the LMF needs to be triggered, and the source LMF sends a user plane update notification (nlmf_location_upnotify) message including user plane information and indicating a modification reason to the AMF.

The user plane information at this time includes information about the source LMF.

The implementation of step 701a is similar to that of step 101 described above, and will not be described again here.

In step 701b, the terminal determines that reselection of the LMF needs to be triggered, and the terminal sends a first message to the AMF, where the first message includes a cause of reestablishing the user plane connection, or the first message indicates a cause of reestablishing the user plane connection.

The implementation of step 701b is similar to that of step 601 described above, and will not be described again here.

In step 701c, the SMF determines that a reselection of the LMF needs to be triggered, and the SMF sends a second message to the AMF, the second message indicating a PDU session related change.

The implementation of step 701c is similar to the implementation of the SMF sending the second message to the AMF in step 401, and will not be described herein.

In step 701d, the AMF determines to trigger a reselection of the LMF.

The implementation is similar to the implementation of the AMF determination in step 201 to trigger the reselection of the LMF, and will not be described in detail herein.

In the embodiment of the disclosure, the steps 701a to 701d may be alternatively performed.

In step 702, the AMF determines a target LMF for user plane location.

In step 703, the AMF sends a fifth message to the SMF, the fifth message being used by the SMF to determine whether to perform a UPF relocation.

The implementation of step 703 is similar to the implementation of step 302 described above, and will not be described in detail here.

In step 704, the SMF determines, based on the fifth message, whether a UPF relocation needs to be performed.

The implementation of step 704 is similar to the implementation of step 503 described above, and will not be described in detail here.

In step 705, after performing the UPF relocation, the SMF sends a response message to the AMF.

The implementation of step 705 is similar to the implementation of steps 504 and 505 described above, and will not be described in detail here.

In step 706, the SMF establishes a user plane connection for the terminal and the target LMF based on the information of the target LMF sent by the AMF.

The implementation of step 706 is similar to that of step 506 described above, and will not be described again here.

In one example, after step 706, steps 103 through 108 may continue to be performed.

In the above embodiment, at least one device of the terminal, the AMF, the source LMF, and the SMF may trigger the reselection of the LMF, and consider the possible influence of the reselection of the LMF on the SMF and the UPF, thereby improving the reliability and high availability of the established user plane connection.

It will be appreciated that the procedure of the present disclosure for providing the above-mentioned method for establishing a user plane connection may be written in the procedure of LoCation Service (LCS) of the third generation partnership project (3rd Generation Partnership Project,3GPP), and may also be applied in the procedure of Ranging-based Service and side-link positioning (Ranging based services and SideLink Positioning, ranging_sl). Of course, other procedures may be written or adapted, as this disclosure is not limited in this regard.

Corresponding to the foregoing embodiment of the application function implementation method, the present disclosure further provides an embodiment of the application function implementation apparatus.

Referring to fig. 8, fig. 8 is a block diagram illustrating a user plane connection establishment apparatus applied to an access and mobility management function AMF according to an exemplary embodiment, comprising:

a determining module 801 configured to determine a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function, LMF, wherein the first device comprises at least one of a terminal, the AMF, a source LMF, and a session management function, SMF;

a first sending module 802, configured to send information of the target LMF to an SMF, where the information of the target LMF is used to instruct the SMF to establish a user plane connection with the target LMF for the terminal.

Referring to fig. 9, fig. 9 is a block diagram of a user plane connection establishment apparatus according to an exemplary embodiment, the apparatus being applied to a session management function SMF, including:

a receiving module 901, configured to receive information of a target location management function LMF sent by an access and mobility management function AMF, where the information of the target LMF is that the AMF determines that a first device triggers reselection of an LMF and determines the target LMF and sends the information to the AMF, and where the first device includes at least one of a terminal, the AMF, a source LMF, and a session management function SMF;

a connection establishment module 902 is configured to establish a user plane connection for a terminal and the target LMF based on information of the target LMF.

Referring to fig. 10, fig. 10 is a block diagram of a user plane connection establishment apparatus according to an exemplary embodiment, the apparatus being applied to a terminal, including:

a second sending module 1001 configured to send a first message to an access and mobility management function AMF in response to determining that a reselection of a location management function LMF needs to be triggered, wherein the first message comprises a reason for reestablishing a user plane connection between the terminal and the LMF; alternatively, the first message indicates a cause of reestablishing the user plane connection.

For the device embodiments, reference is made to the description of the method embodiments for the relevant points, since they essentially correspond to the method embodiments. The apparatus embodiments described above are merely illustrative, wherein the elements described above as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the objectives of the disclosed solution. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

Accordingly, the present disclosure also provides a computer readable storage medium storing a computer program for executing any one of the above-described user plane connection establishment methods.

Correspondingly, the disclosure further provides a system for establishing a user plane connection, and referring to fig. 11, the system may include:

an access and mobility management function AMF1101, where the AMF1101 is configured to execute the user plane connection establishment method described in any one of the above AMF sides;

A session management function SMF1102, where the SMF1102 is configured to perform a method for establishing a user plane connection according to any one of the foregoing SMFs;

a terminal 1103, where the terminal 1103 is configured to execute the method for establishing a user plane connection described in any one of the above terminal sides;

a location management function LMF1104, the LMF1104 being configured to establish a user plane connection with the terminal.

Wherein the number of terminals is plural in fig. 11. The LMFs 1104 may include a source LMF1104-1 and a target LMF1104-2, in particular.

UPF may also be included in the system.

Correspondingly, the disclosure also provides a device for establishing the user plane connection, which comprises:

a processor;

a memory for storing processor-executable instructions;

the processor is configured to execute the user plane connection establishment method on any one of the access network element sides.

As shown in fig. 12, fig. 12 is a schematic structural diagram of a user plane connection establishment apparatus 1200 according to an exemplary embodiment. The apparatus 1200 may be provided as an access network element including, but not limited to, an AMF, an SMF, a source LMF, etc. Referring to fig. 12, the apparatus 1200 includes a processing component 1222, a wireless transmit/receive component 1224, an antenna component 1226, and a signal processing portion specific to a wireless interface, and the processing component 1222 may further include at least one processor.

One of the processors in processing component 1222 may be configured to perform the user plane connection establishment method described on the AMF, SMF, source LMF side of any of the above.

Correspondingly, the disclosure also provides a device for establishing the user plane connection, which comprises:

a processor;

a memory for storing processor-executable instructions;

the processor is configured to execute the user plane connection establishment method of any one of the terminal sides.

Fig. 13 is a block diagram of an electronic device 1300, according to an example embodiment. For example, the electronic device 1300 may be a mobile phone, tablet computer, electronic book reader, multimedia playing device, wearable device, vehicle terminal, ipad, smart television, etc.

Referring to fig. 13, an electronic device 1300 may include one or more of the following components: a processing component 1302, a memory 1304, a power component 1306, a multimedia component 1308, an audio component 1310, an input/output (I/O) interface 1312, a sensor component 1316, and a communication component 1318.

The processing component 1302 generally controls overall operation of the electronic device 1300, such as operations associated with display, telephone calls, data communications, camera operations, and recording operations. The processing component 1302 may include one or more processors 1320 to execute instructions to perform all or part of the steps of the user plane connection establishment method described above. Further, the processing component 1302 can include one or more modules that facilitate interactions between the processing component 1302 and other components. For example, the processing component 1302 may include a multimedia module to facilitate interaction between the multimedia component 1308 and the processing component 1302. As another example, the processing component 1302 may read executable instructions from a memory to implement the steps of a user plane connection establishment method provided by the above embodiments.

The memory 1304 is configured to store various types of data to support operations at the electronic device 1300. Examples of such data include instructions for any application or method operating on the electronic device 1300, contact data, phonebook data, messages, pictures, videos, and so forth. The memory 1304 may be implemented by any type or combination of volatile or nonvolatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disk.

The power supply assembly 1306 provides power to the various components of the electronic device 1300. The power components 1306 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power for the electronic device 1300.

The multimedia component 1308 includes a display screen between the electronic device 1300 and a user that provides an output interface. In some embodiments, the multimedia component 1308 includes a front-facing camera and/or a rear-facing camera. When the electronic device 1300 is in an operational mode, such as a shooting mode or a video mode, the front camera and/or the rear camera may receive external multimedia data. Each front camera and rear camera may be a fixed optical lens system or have focal length and optical zoom capabilities.

The audio component 1310 is configured to output and/or input audio signals. For example, the audio component 1310 includes a Microphone (MIC) configured to receive external audio signals when the electronic device 1300 is in an operational mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signals may be further stored in the memory 1304 or transmitted via the communication component 1318. In some embodiments, the audio component 1310 also includes a speaker for outputting audio signals.

The I/O interface 1312 provides an interface between the processing component 1302 and peripheral interface modules, which may be a keyboard, click wheel, buttons, etc. These buttons may include, but are not limited to: homepage button, volume button, start button, and lock button.

The sensor assembly 1316 includes one or more sensors for providing status assessment of various aspects of the electronic device 1300. For example, the sensor assembly 1316 may detect an on/off state of the electronic device 1300, a relative positioning of the components, such as a display and keypad of the electronic device 1300, the sensor assembly 1316 may also detect a change in position of the electronic device 1300 or a component of the electronic device 1300, the presence or absence of a user in contact with the electronic device 1300, an orientation or acceleration/deceleration of the electronic device 1300, and a change in temperature of the electronic device 1300. The sensor assembly 1316 may include a proximity sensor configured to detect the presence of nearby objects without any physical contact. The sensor assembly 1316 may also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 1316 may also include an acceleration sensor, a gyroscopic sensor, a magnetic sensor, a pressure sensor, or a temperature sensor.

The communication component 1318 is configured to facilitate communication between the electronic device 1300 and other devices, either wired or wireless. The electronic device 1300 may access a wireless network based on a communication standard, such as Wi-Fi,2G,3G,4G, or 5G, or a combination thereof. In one exemplary embodiment, the communication component 1318 receives broadcast signals or broadcast related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 1318 further includes a Near Field Communication (NFC) module to facilitate short range communications. For example, the NFC module may be implemented based on Radio Frequency Identification (RFID) technology, infrared data association (IrDA) technology, ultra Wideband (UWB) technology, bluetooth (BT) technology, and other technologies.

In an exemplary embodiment, the electronic device 1300 may be implemented by one or more Application Specific Integrated Circuits (ASICs), digital Signal Processors (DSPs), digital Signal Processing Devices (DSPDs), programmable Logic Devices (PLDs), field Programmable Gate Arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic elements for performing the user plane connection establishment method described above.

In an exemplary embodiment, a non-transitory machine-readable storage medium is also provided, such as a memory 1304 comprising instructions executable by the processor 1320 of the electronic device 1300 to perform the user plane connection establishment method described above. For example, the non-transitory computer readable storage medium may be ROM, random Access Memory (RAM), CD-ROM, magnetic tape, floppy disk, optical data storage device, etc.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This disclosure is intended to cover any adaptations, uses, or adaptations of the disclosure following the general principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (36)

1. A method for establishing a user plane connection, the method being performed by an access and mobility management function AMF, comprising:

determining a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function LMF, wherein the first device comprises at least one of a terminal, the AMF, a source LMF, and a session management function SMF;

And sending the information of the target LMF to an SMF, wherein the information of the target LMF is used for indicating the SMF to establish user plane connection for the terminal and the target LMF.

2. The method according to claim 1, wherein, in case the first device comprises a terminal, the determining that the first device triggers a reselection of a location management function, LMF, comprises:

determining, in response to receiving a first message sent by a terminal, that the terminal triggers reselection of the LMF, wherein the first message includes a cause of reestablishing the user plane connection; alternatively, the first message indicates a cause of reestablishing the user plane connection.

3. The method of claim 2, wherein the first message comprises any one of:

the uplink non-access stratum transmits an UL NAS TRANSPORT message;

a service request message.

4. The method of claim 2, wherein the first message comprises:

and the first user plane information comprises information of the source LMF.

5. The method of claim 1, wherein the determining that the first device triggered reselection of the location management function, LMF, if the first device included an SMF, comprises:

And in response to receiving a second message sent by the SMF, determining that the SMF triggers reselection of the LMF, wherein the second message is used for indicating a PDU session related change.

6. The method of claim 5, wherein the method further comprises:

and subscribing to a PDU session management context state reminding service of the SMF before receiving the second message sent by the SMF.

7. The method of claim 1, wherein, in the case where the first device comprises an AMF, the determining that the first device triggers a reselection of a location management function, LMF, comprises any one of:

in response to determining that the state of the terminal changes, determining that the AMF triggers reselection of the LMF;

determining that the AMF triggers reselection of the LMF based on a third message sent by the SMF, the third message including information of a user plane function UPF and/or information related to the LMF;

and determining that the AMF triggers reselection of the LMF based on a fourth message sent by the terminal, wherein the fourth message comprises the terminal mobility information.

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

And sending a fifth message to the SMF, wherein the fifth message is used for determining whether to execute UPF relocation by the SMF.

9. The method of claim 8, wherein the fifth message comprises:

PDU session update request message.

10. The method of claim 8, wherein the fifth message comprises, when the SMF subscribes to a status notification of the LMF:

a notification message for notifying the SMF of a state change of the LMF.

11. The method of claim 8, wherein the fifth message is for notifying the SMF of at least one of:

the LMF connected with the user plane of the terminal is changed;

information of the target LMF.

12. The method of any one of claims 1-11, wherein the information of the target LMF comprises at least one of:

an internet protocol, IP, address of the target LMF;

a fully qualified domain name, FQDN, of the target LMF;

identification of the target LMF;

service area of the target LMF.

13. The method of claim 8, wherein the method further comprises:

based on the information of the target LMF, an insertion or relocation process of an intermediate session management function I-SMF is triggered.

14. The method of claim 8, wherein the method further comprises:

and receiving a response message sent by the SMF after repositioning the UPF.

15. The method of any one of claims 1-14, wherein the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

16. A method for establishing a user plane connection, the method being performed by a session management function, SMF, comprising:

receiving information of a target Location Management Function (LMF) sent by an access and mobility management function (AMF), wherein the information of the target LMF is at least one of a terminal, the AMF, a source LMF and a Session Management Function (SMF) after the AMF determines that first equipment triggers reselection of the LMF and determines the target LMF;

and establishing user plane connection for the terminal and the target LMF based on the information of the target LMF.

17. The method of claim 16, wherein the method further comprises:

in response to determining that a reselection of the location management function, LMF, needs to be triggered, a second message is sent to the AMF, the second message indicating a PDU session related change.

18. The method of claim 17, wherein the method further comprises:

determining that the AMF subscribes to a PDU session management context state alert service of the SMF.

19. The method of claim 16, wherein the method further comprises:

receiving a fifth message sent by the AMF;

based on the fifth message, it is determined whether a UPF relocation needs to be performed.

20. The method of claim 19, wherein the fifth message comprises:

PDU session update request message.

21. The method of claim 19, wherein the fifth message comprises, when the SMF subscribes to a status notification of the LMF:

a notification message for notifying the SMF of a state change of the LMF.

22. The method of claim 19, wherein the fifth message is used to notify the SMF of at least one of:

the LMF connected with the user plane of the terminal is changed;

information of the target LMF.

23. A method according to any one of claims 16-22, wherein the information of the target LMF comprises at least one of:

an internet protocol, IP, address of the target LMF;

A fully qualified domain name, FQDN, of the target LMF;

identification of the target LMF;

service area of the target LMF.

24. The method according to any one of claims 19-22, further comprising:

responsive to determining that a UPF relocation is required to be performed, determining a relocated UPF;

and sending a response message to the AMF.

25. A method as recited in claim 24, wherein the establishing a user plane connection for a terminal with the target LMF based on the information of the target LMF comprises:

and establishing the user plane connection for the terminal and the target LMF through the relocated UPF based on the information of the target LMF.

26. The method of any one of claims 16-25, wherein the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

27. A method for establishing a user plane connection, the method being performed by a terminal and comprising:

in response to determining that reselection of a location management function, LMF, needs to be triggered, sending a first message to an access and mobility management function, AMF, wherein the first message includes a cause of reestablishing a user plane connection between the terminal and the LMF; alternatively, the first message indicates a cause of reestablishing the user plane connection.

28. The method of claim 27, wherein the first message comprises any one of:

the uplink non-access stratum transmits an UL NAS TRANSPORT message;

a service request message.

29. The method of claim 27 or 28, wherein the first message comprises:

and the first user plane information comprises information of the source LMF.

30. The method of any one of claims 27-29, wherein the reselection of the LMF comprises:

releasing the user plane connection between the terminal and the source LMF; and

and establishing user plane connection between the terminal and the target LMF.

31. A user plane connection establishment apparatus, wherein the apparatus is applied to an access and mobility management function AMF, and comprises:

a determining module configured to determine a target LMF for user plane location in response to determining that a first device triggers reselection of a location management function, LMF, the first device comprising at least one of a terminal, the AMF, a source LMF, and a session management function, SMF;

and the first sending module is configured to send the information of the target LMF to the SMF, wherein the information of the target LMF is used for indicating the SMF to establish user plane connection with the target LMF for the terminal.

32. A user plane connection establishment apparatus, characterized in that the apparatus is applied to a session management function SMF, comprising:

a receiving module configured to receive information of a target location management function, LMF, sent by an access and mobility management function, AMF, wherein the information of the target LMF is that the AMF determines that a first device triggers reselection of an LMF and determines the target LMF and sends the information to the AMF, and wherein the first device includes at least one of a terminal, the AMF, a source LMF, and a session management function, SMF;

and the connection establishment module is configured to establish user plane connection for the terminal and the target LMF based on the information of the target LMF.

33. A user plane connection establishment apparatus, wherein the apparatus is applied to a terminal, and comprises:

a second sending module configured to send a first message to an access and mobility management function, AMF, in response to determining that a reselection of a location management function, LMF, needs to be triggered, wherein the first message includes a cause of reestablishing the user plane connection; alternatively, the first message indicates a cause of reestablishing the user plane connection.

34. A computer readable storage medium, characterized in that the storage medium stores a computer program for executing the user plane connection establishment method of any of the preceding claims 1-30.

35. A user plane connection establishment system, comprising:

an access and mobility management function, AMF, for performing the user plane connection establishment method of any one of the preceding claims 1-15;

session management function, SMF, for performing a user plane connection establishment method as claimed in any of the preceding claims 16-26;

a terminal for performing the user plane connection establishment method of any one of the preceding claims 27-30;

and the Location Management Function (LMF) is used for establishing user plane connection with the terminal.

36. A user plane connection establishment apparatus, comprising:

a processor;

a memory for storing processor-executable instructions;

wherein the processor is configured to perform the user plane connection establishment method of any of the preceding claims 1-30.