Patent Description:
If there is no data transmission for a certain period of time in a session (PDU session), the SMF may terminate the corresponding session. That is, the user plane connection of the corresponding session may be deactivated. At this time, properly setting the certain period of time for each session is required for efficient communication.

Document <CIT> discloses a method performed by a Session Management Function, SMF, wherein the SMF transmits, to a Network Data Analytics Function, NWDAF, a request for Analytics, and determines a value of inactivity timer for a Packet Data Unit, PDU, session based on the Analytics.

Document <CIT> discloses a method for providing user plane function (UPF) with inactivity timer value for particular protocol data unit (PDU) session.

The SMF may receive analytics from NWDAF and, based on this, determine an appropriate deactivation timer value suitable for the session.

The specification may have various effects.

For example, through the procedure disclosed herein, the SMF may determine an appropriate inactivity timer for the PDU session to efficiently manage user plane resources to provide an optimized UP.

Effects that can be obtained through specific examples of the present specification are not limited to the effects listed above. For example, various technical effects that a person having ordinary skill in the related art can understand or derive from this specification may exist. Accordingly, the specific effects of the present specification are not limited to those explicitly described herein, and may include various effects that can be understood or derived from the technical characteristics of the present specification.

Evolution of 3GPP LTE includes LTE-A (advanced), LTE-A Pro, and/or <NUM> NR (new radio).

Also, parentheses used in the present disclosure may mean "for example". In detail, when it is shown as "control information (PDCCH)", "PDCCH" may be proposed as an example of "control information". In other words, "control information" in the present disclosure is not limited to "PDCCH", and "PDDCH" may be proposed as an example of "control information". In addition, even when shown as "control information (i.e., PDCCH)", "PDCCH" may be proposed as an example of "control information".

AI refers to the field of studying artificial intelligence or the methodology that can create it, and machine learning refers to the field of defining various problems addressed in the field of AI and the field of methodology to solve them. Machine learning is also defined as an algorithm that increases the performance of a task through steady experience on a task.

Robot means a machine that automatically processes or operates a given task by its own ability. In particular, robots with the ability to recognize the environment and make self-determination to perform actions can be called intelligent robots. Robots can be classified as industrial, medical, home, military, etc., depending on the purpose or area of use. The robot can perform a variety of physical operations, such as moving the robot joints with actuators or motors. The movable robot also includes wheels, brakes, propellers, etc., on the drive, allowing it to drive on the ground or fly in the air.

Autonomous driving means a technology that drives on its own, and autonomous vehicles mean vehicles that drive without user's control or with minimal user's control. For example, autonomous driving may include maintaining lanes in motion, automatically adjusting speed such as adaptive cruise control, automatic driving along a set route, and automatically setting a route when a destination is set. The vehicle covers vehicles equipped with internal combustion engines, hybrid vehicles equipped with internal combustion engines and electric motors, and electric vehicles equipped with electric motors, and may include trains, motorcycles, etc., as well as cars. Autonomous vehicles can be seen as robots with autonomous driving functions.

Extended reality is collectively referred to as VR, AR, and MR. VR technology provides objects and backgrounds of real world only through computer graphic (CG) images. AR technology provides a virtual CG image on top of a real object image. MR technology is a CG technology that combines and combines virtual objects into the real world. MR technology is similar to AR technology in that they show real and virtual objects together. However, there is a difference in that in AR technology, virtual objects are used as complementary forms to real objects, while in MR technology, virtual objects and real objects are used as equal personalities.

NR supports multiples numerologies (and/or multiple subcarrier spacings (SCS)) to support various <NUM> services. For example, if SCS is <NUM>, wide area can be supported in traditional cellular bands, and if SCS is <NUM>/<NUM>, dense-urban, lower latency, and wider carrier bandwidth can be supported. If SCS is <NUM> or higher, bandwidths greater than <NUM> can be supported to overcome phase noise.

Referring to <FIG>, a first wireless device <NUM> and a second wireless device <NUM> may transmit/receive radio signals to/from an external device through a variety of RATs (e.g., LTE and NR).

In <FIG>, {the first wireless device <NUM> and the second wireless device <NUM>} may correspond to at least one of {the wireless device 100a to 100f and the BS <NUM>}, {the wireless device 100a to 100f and the wireless device 100a to 100f} and/or {the BS <NUM> and the BS <NUM>} of <FIG>.

The first wireless device <NUM> may include at least one transceiver, such as a transceiver <NUM>, at least one processing chip, such as a processing chip <NUM>, and/or one or more antennas <NUM>.

The processing chip <NUM> may include at least one processor, such a processor <NUM>, and at least one memory, such as a memory <NUM>. It is exemplarily shown in <FIG> that the memory <NUM> is included in the processing chip <NUM>. Additional and/or alternatively, the memory <NUM> may be placed outside of the processing chip <NUM>.

The processor <NUM> may control the memory <NUM> and/or the transceiver <NUM> and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts described in the present disclosure. For example, the processor <NUM> may process information within the memory <NUM> to generate first information/signals and then transmit radio signals including the first information/signals through the transceiver <NUM>. The processor <NUM> may receive radio signals including second information/signals through the transceiver <NUM> and then store information obtained by processing the second information/signals in the memory <NUM>.

The memory <NUM> may be operably connectable to the processor <NUM>. The memory <NUM> may store various types of information and/or instructions. The memory <NUM> may store a software code <NUM> which implements instructions that, when executed by the processor <NUM>, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code <NUM> may implement instructions that, when executed by the processor <NUM>, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the software code <NUM> may control the processor <NUM> to perform one or more protocols. For example, the software code <NUM> may control the processor <NUM> to perform one or more layers of the radio interface protocol.

Herein, the processor <NUM> and the memory <NUM> may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver <NUM> may be connected to the processor <NUM> and transmit and/or receive radio signals through one or more antennas <NUM>. Each of the transceiver <NUM> may include a transmitter and/or a receiver. The transceiver <NUM> may be interchangeably used with radio frequency (RF) unit(s). In the present disclosure, the first wireless device <NUM> may represent a communication modem/circuit/chip.

The second wireless device <NUM> may include at least one transceiver, such as a transceiver <NUM>, at least one processing chip, such as a processing chip <NUM>, and/or one or more antennas <NUM>.

The processor <NUM> may control the memory <NUM> and/or the transceiver <NUM> and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts described in the present disclosure. For example, the processor <NUM> may process information within the memory <NUM> to generate third information/signals and then transmit radio signals including the third information/signals through the transceiver <NUM>. The processor <NUM> may receive radio signals including fourth information/signals through the transceiver <NUM> and then store information obtained by processing the fourth information/signals in the memory <NUM>.

Herein, the processor <NUM> and the memory <NUM> may be a part of a communication modem/circuit/chip designed to implement RAT (e.g., LTE or NR). The transceiver <NUM> may be connected to the processor <NUM> and transmit and/or receive radio signals through one or more antennas <NUM>. Each of the transceiver <NUM> may include a transmitter and/or a receiver. The transceiver <NUM> may be interchangeably used with RF unit. In the present disclosure, the second wireless device <NUM> may represent a communication modem/circuit/chip.

As an example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in the one or more processors <NUM> and <NUM>. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software and the firmware or software may be configured to include the modules, procedures, or functions. Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be included in the one or more processors <NUM> and <NUM> or stored in the one or more memories <NUM> and <NUM> so as to be driven by the one or more processors <NUM> and <NUM>. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software in the form of code, commands, and/or a set of commands.

The one or more transceivers <NUM> and <NUM> may be connected to the one or more antennas <NUM> and <NUM> and the one or more transceivers <NUM> and <NUM> may be configured to transmit and receive user data, control information, and/or radio signals/channels, mentioned in the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure, through the one or more antennas <NUM> and <NUM>. In the present disclosure, the one or more antennas <NUM> and <NUM> may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

The one or more transceivers <NUM> and <NUM> may convert received user data, control information, radio signals/channels, etc., from RF band signals into baseband signals in order to process received user data, control information, radio signals/channels, etc., using the one or more processors <NUM> and <NUM>. The one or more transceivers <NUM> and <NUM> may convert the user data, control information, radio signals/channels, etc., processed using the one or more processors <NUM> and <NUM> from the base band signals into the RF band signals. For example, the one or more transceivers <NUM> and <NUM> can up-convert OFDM baseband signals to OFDM signals by their (analog) oscillators and/or filters under the control of the one or more processors <NUM> and <NUM> and transmit the up-converted OFDM signals at the carrier frequency. The one or more transceivers <NUM> and <NUM> may receive OFDM signals at a carrier frequency and down-convert the OFDM signals into OFDM baseband signals by their (analog) oscillators and/or filters under the control of the one or more processors <NUM> and <NUM>.

In the implementations of the present disclosure, a UE may operate as a transmitting device in uplink (UL) and as a receiving device in downlink (DL). In the implementations of the present disclosure, a BS may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device <NUM> acts as the UE, and the second wireless device <NUM> acts as the BS. For example, the processor(s) <NUM> connected to, mounted on or launched in the first wireless device <NUM> may be configured to perform the UE behavior according to an implementation of the present disclosure or control the transceiver(s) <NUM> to perform the UE behavior according to an implementation of the present disclosure. The processor(s) <NUM> connected to, mounted on or launched in the second wireless device <NUM> may be configured to perform the BS behavior according to an implementation of the present disclosure or control the transceiver(s) <NUM> to perform the BS behavior according to an implementation of the present disclosure.

The communication unit <NUM> may include a communication circuit <NUM> and transceiver(s) <NUM>. For example, the communication circuit <NUM> may include the one or more processors <NUM> and <NUM> of <FIG> and/or the one or more memories <NUM> and <NUM> of <FIG>. For example, the transceiver(s) <NUM> may include the one or more transceivers <NUM> and <NUM> of <FIG> and/or the one or more antennas <NUM> and <NUM> of <FIG>. The control unit <NUM> is electrically connected to the communication unit <NUM>, the memory unit <NUM>, and the additional components <NUM> and controls overall operation of each of the wireless devices <NUM> and <NUM>. For example, the control unit <NUM> may control an electric/mechanical operation of each of the wireless devices <NUM> and <NUM> based on programs/code/commands/information stored in the memory unit <NUM>.

As an example, the control unit <NUM> may be configured by a set of a communication control processor, an application processor (AP), an electronic control unit (ECU), a graphical processing unit, and a memory control processor. As another example, the memory unit <NUM> may be configured by a RAM, a DRAM, a ROM, a flash memory, a volatile memory, a non-volatile memory, and/or a combination thereof.

Referring to <FIG>, a UE <NUM> may correspond to the first wireless device <NUM> of <FIG> and/or the wireless device <NUM> or <NUM> of <FIG>.

The processor <NUM> may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The processor <NUM> may be configured to control one or more other components of the UE <NUM> to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. Layers of the radio interface protocol may be implemented in the processor <NUM>. The processor <NUM> may include ASIC, other chipset, logic circuit and/or data processing device. The processor <NUM> may be an application processor. The processor <NUM> may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), a modem (modulator and demodulator). An example of the processor <NUM> may be found in SNAPDRAGON™ series of processors made by Qualcomm®, EXYNOS™ series of processors made by Samsung®, a series of processors made by Apple®, HELIO™ series of processors made by MediaTek®, ATOM™ series of processors made by Intel® or a corresponding next generation processor.

<FIG> shows an example of a <NUM> system architecture to which the implementation of the present specification is applied.

The <NUM> system (5GS; <NUM> system) structure consists of the following network functions (NFs).

In addition, the following network functions may be considered.

<FIG> shows the <NUM> system structure of a non-roaming case using a reference point representation that shows how various network functions interact with each other.

In <FIG>, UDSF, NEF and NRF are not described for clarity of the point-to-point diagram. However, all network functions shown may interact with UDSF, UDR, NEF and NRF as needed.

For clarity, the connection between the UDR and other NFs (e.g., PCFs) is not shown in <FIG>. For clarity, the connection between NWDAF and other NFs (e.g. PCFs) is not shown in <FIG>.

The <NUM> system architecture includes the following reference points.

The following reference points show the interactions that exist between NF services in NF.

In some cases, it may be necessary to connect two NFs to each other to service the UE.

Selective activation and deactivation of the UP connection of the existing PDU Session may be performed.

A UE may establish multiple PDU sessions. Activating the UP connection of the existing PDU session may activate the UE-CN user plane connection (i.e., data radio bearer and N3 tunnel).

For the UE in the CM-IDLE state in 3GPP access, either UE or Network-Triggered Service Request procedure may support independent activation of UP connection of existing PDU Session. For the UE in the CM-IDLE state in non-3GPP access, UE-Triggered Service Request procedure allows the re-activation of UP connection of existing PDU Sessions, and may support independent activation of UP connection of existing PDU Session.

A UE in the CM-CONNECTED state invokes a Service Request procedure to request the independent activation of the UP connection of existing PDU Sessions.

Network Triggered re-activation of UP connection of existing PDU Sessions is handled as follows:.

In addition to the above, a PDU Session may be established as an always-on PDU Session.

The deactivation of the UP connection of an existing PDU Session causes the corresponding data radio bearer and N3 tunnel to be deactivated. The UP connection of different PDU Sessions can be deactivated independently when a UE is in CM-CONNECTED state in 3GPP access or non-3GPP access. At the deactivation of the UP of a PDU Session using a N9 tunnel whose end-point is controlled by an I-SMF, the N9 tunnel is preserved. If a PDU Session is an always-on PDU Session, the SMF should not deactivate a UP connection of this PDU Session due to inactivity.

<FIG> shows deactivation of UP connections for PDU sessions.

UP connection (i.e. data radio bearer and N3 tunnel) for an established PDU Session of a UE in CM-CONNECTED state may be deactivated.

The SMF may decide to release the UPF of N3 terminating point. In that case the SMF proceeds with step <NUM> and step <NUM>. Otherwise, if the SMF decides to keep the UPF of N3 terminating points, the SMF proceeds with step <NUM>.

The SMF may initiate an N4 Session Release procedure to release the intermediate UPF of N3 terminating point. If there are multiple intermediate UPFs, this step can be performed for each UPFs to be released. The SMF needs to initiate N4 Session Modification procedure to the UPF (i.e. N9 terminating point or PDU Session Anchor) connecting to the released UPF in step <NUM>.

If the intermediate UPF(s) of N3 terminating point is released in step <NUM>, the SMF may initiate an N4 Session Modification procedure towards the UPF (PDU Session Anchor or another intermediate UPF) connecting to the released UPF, indicating the need to remove CN Tunnel Info for N9 tunnel of the corresponding PDU Session. In this case, the UPF connecting to the released UPF buffers the DL packets for this PDU Session or drops the DL packets for this PDU session or forwards the DL packets for this PDU session to the SMF, based on buffering instruction provided by the SMF. If the PDU Session corresponds to a LADN and the UE moved out of the LADN service area, the SMF may notify the UPF connecting to the released UPF to discard downlink data for the PDU Sessions and/or to not provide further Data Notification messages.

Otherwise, N4 Session Modification procedure may occur toward N3 terminating point.

If the UPF of N3 terminating point is not released in step <NUM>, the SMF may initiate an N4 Session Modification procedure indicating the need to remove AN Tunnel Info for N3 tunnel of the corresponding PDU Session. In this case, the UPF may buffer the DL packets for this PDU Session or drop the DL packets for this PDU session or forward the DL packets for this PDU session to the SMF, based on buffering instruction provided by the SMF. If the PDU Session corresponds to a LADN and the UE moved out of the LADN service area, the SMF may notify the UPF to discard downlink data for the PDU Sessions and/or to not provide further Data Notification messages.

The SMF invokes the Namf_Communication_N1N2MessageTransfer service operation (PDU Session ID, N2 SM Information (N2 Resource Release Request (PDU Session ID))) to release the NG-RAN resources associated with the PDU Session.

The AMF may send the N2 PDU Session Resource Release Command including N2 SM information (N2 Resource Release Request (PDU Session ID)) received from the SMF via N2 to the NG-RAN.

The NG-RAN may issue NG-RAN specific signaling exchange (e.g. RRC Connection Reconfiguration) with the UE to release the NG-RAN resources related to the PDU Session received from the AMF in step <NUM>. When a User Plane connection for a PDU Session is released, the AS layer in the UE indicates it to the NAS layer.

If the UE is in RRC Inactive state, this step is skipped. When the UE becomes RRC Connected state from RRC Inactive state, the NG-RAN and UE may synchronize the released radio resources for the deactivated PDU Session.

The NG-RAN may acknowledge the N2 PDU Session Resource Release Command to the AMF including N2 SM Resource Release Ack (User Location Information, Secondary RAT Usage Data).

The AMF may invoke the Nsmf_PDUSession_UpdateSMContext service operation (N2 SM Information(Secondary RAT Usage Data)) to acknowledge the Namf service received in step <NUM>.

The SMF may configure the UPF to report inactivity by providing an inactivity timer for the PDU session to the UPF during the N4 session establishment/modification procedure related to the PDU session.

The value of the inactivity timer is related to the inactivity detection time, and the inactivity detection time defines the time at which time measurement is stopped when no packets are received. The inactivity timer associated with the inactivity detection time restarts at the end of each transmitted packet.

The UP inactivity timer may include the number of seconds of inactivity monitored by the UP function (i.e., UPE).

The user plane inactivity timer IE contains the number of seconds of inactivity monitored by the UP function.

The User Plane Inactivity Timer field shall be encoded as an Unsigned32 binary integer value. The timer value "<NUM>" shall be interpreted as an indication that user plane inactivity detection and reporting is stopped.

If the inactivity timer provided by the SMF is not appropriate for the PDU session, for example, if it takes too long for the UPF to detect PDU session inactivity relative to the communication pattern for the PDU session, then the PDU session may become inactive and UP resources (i.e., data radio bearers and N3 tunnels) may be allocated unnecessarily even if there is no data transmission for a while. In addition, UPF reallocation may be performed because an activated PDU session must be handled in a handover scenario. This handover process for the PDU session may be unnecessary when there is no data transmission for a while because the PDU session is inactive.

Disclosures described later in this specification may be implemented in one or more combinations (e.g., a combination including at least one of the contents described below). Each of the drawings represents an embodiment of each disclosure, but the embodiments of the drawings may be implemented in combination with each other.

Description of the method proposed in the disclosure of this specification may be composed of a combination of one or more operations/configurations/steps described below. The following methods described below may be performed or used in combination or complementary.

The following drawings are made to explain a specific example of the present specification. Since the names of specific devices or names of specific signals/messages/fields described in the drawings are provided as examples, the technical features of the present specification are not limited to the specific names used in the drawings below.

It may be considered that SMF's determination of an appropriate inactivity timer for a PDU session will help to efficiently manage user plane resources resulting in UP optimization.

In the proposed solution, SMF may use the UE Communication Analytics output of NWDAF for CN-initiated selective deactivation of UP connections of existing PDU sessions.

That is, the SMF may determine i) whether to configure the UPF to report the inactivity of the established PDU session using the output of the UE Communication Analytics and ii) the inactivity timer for the PDU session provided to the UPF if reporting is required.

<FIG> shows the disclosure of this specification.

The message transmitted for the request or subscription may include Analytics Filter information and Target of Analytics Reporting information. DNN and S-NSSAI information may be included in the message as Analytics Filter information. One UE information (i.e., SUPI) or UE group information (i.e., Internal Group Identifier) may be included in the message as Target of Analytics Reporting information. The message transmitted for the above request or subscription may include Area of Interest information.

The message transmitted for the above request or subscription may include a request for predictions or statistics, which are analytics output.

For providing requested analytics, NWDAF may subscribe, to SMF, for a service that provides information related to UE communication.

Nsmf_EventExposure_Subscribe may be used for the subscription. The information provided from the SMF may include information in Table <NUM>.

For providing requested analytics, NWDAF may subscribe, to AMF, for a service that provides information related to Type Allocation code (TAC).

Namf_EventExposure_Subscribe may be used for the subscription.

The TAC information may include terminal model and terminal manufacturer information. The reason why TAC information is provided from AMF is that UEs having the same TAC information can have similar communication types.

NWDAF may compute requested analytics. In step <NUM>, if SMF requested to provide statistics output, the UE communication analytics computed above is statistics information. If SMF requested to provide output for predictions in step <NUM>, the UE communication analytics calculated above is predictions information.

NWDAF may provide UE communication analytics to SMF. If Nnwdaf_AnalyticsInfo_Request is received from SMF in step <NUM>, NWDAF may provide the analytics information to SMF through Nnwdaf_AnalyticsInfo_Response. If Nnwdaf_AnalyticsSubscription_Subscribe is received from SMF in step <NUM>, NWDAF may provide the analytics information to SMF through Nnwdaf_Analytics_Subscription_Notify.

If the UE Communication analytics output/information provided by the NWDAF to the SMF is statistics information, the information in Table <NUM> may be included.

If the UE Communication analytics output/information provided by the NWDAF to the SMF is predictions information, the information in Table <NUM> may be included.

The SMF may determine the Inactivity Timer value of the PDU Session to be provided to the UPF based on the UE Communication analytics output/information received from the NWDAF. This decision may include a decision on whether to configure the UPF to report inactivity for the PDU Session or whether to stop the UPF from reporting inactivity for the PDU Session. By setting the Inactivity Timer value to <NUM>, the SMF may configure the UPF not to report inactivity or to stop.

The SMF may determine whether to designate a PDU Session as an always-on PDU Session, based on the UE Communication analytics output/information received from the NWDAF.

The PDU Session is a PDU Session for DNN/S-NSSAI included in the NWDAF output.

The PDU Session may be for a specific UE or a specific group of UEs.

The PDU Session may be in an activated state in a specific region (cells, TAs, UPF serving area, etc.).

For example, if the UE communication related to S-NSSAI/DNN (that is, the communication characteristics/pattern of PDU Session related to S-NSSAI/DNN) is periodic and the period is long, the Inactivity Timer for the corresponding PDU Session is determined with a small value. By providing this to the UPF, the UPF may detect inactivity within a short time after communication is terminated and report it to the SMF. As another example, if UE communication related to S-NSSAI/DNN is not periodic, an inactivity timer for the corresponding PDU session may be determined as a large value and provided to the UPF. This is to prevent prematurely deactivating the user plane of the PDU Session due to the report of inactivity by the UPF when the Inactivity Timer is set to a small value and provided to the UPF. As another example, if the period of UE communication related to S-NSSAI/DNN is very small, the UPF may be configured not to report inactivity or stopped.

<NUM>-<NUM>. If NWDAF has received Nnwdaf_AnalyticsSubscription_Subscribe from SMF in step <NUM>, NWDAF may compute new analytics based on information provided from SMF and/or AMF (information described in step <NUM>). And, the newly computed analytics information may be provided to SMF through Nnwdaf_AnalyticsSubscription_Notify.

When the SMF determines the Inactivity Timer value of the PDU Session, the SMT may provide it to the UPF. The provision may be performed during the procedure of PDU Session Establishment or PDU Session Modification.

As described above, when SMF performs UP (User Plane) optimization using NWDAF analytics, UE Communication Analytics may be extended and used, and other analytics (e.g., UE mobility analytics, User Data Congestion Analytics) together with or in addition to UE Communication Analytics may also be used.

When an SMF subscribes to or requests NWDAF analytics for UP optimization, it may always do so, or it may be performed based on various conditions/reasons as shown below. However, the subscription/request may be performed based on various circumstances without being limited thereto.

<FIG> shows a procedure of SMF according to the disclosure of the present specification.

The requested analytics may be UE Communication Analytics.

The message may include DNN and S-NSSAI. DNN and S-NSSAI may be related to a specific session (PDU session).

The Analytics request message may include Subscription Permanent Identifier (SUPI) information, Internal Group Identifier information, and Area of Interest information.

SMF may receive analytics from NWDAF.

The analytics may be related to the specific session described above in step <NUM>.

The SMF may determine a inactivation timer value based on analytics.

The inactivity timer value may be related to the specific session. An appropriate inactivation timer value suitable for characteristics of a session may be set.

The inactivation timer value may be zero.

The SMF may transmit the inactivation timer value to the UPF.

When there is no data transmission for the specific session for a time corresponding to the inactivity timer value, the UPF may detect this and notify the SMF.

When the SMF recognizes that there is no data transmission for the specific session for a time corresponding to the inactivation timer value, the SMF may terminate the specific session (i.e., deactivate the UP connection).

SMF may receive new Analytics from NWDAF.

A new inactivation timer value may be determined based on the new Analytics.

The new inactivation timer value may be transmitted through UPF.

<FIG> shows a procedure of NWDAF according to the disclosure of this specification.

The Analytics request message may include DNN and S-NSSAI. DNN and S-NSSAI may be related to a specific session (PDU session).

NWDAF may receive information for analytics from at least one SMF.

NWDAF may request information for analytics from at least one SMF and receive it as a response. The SMF of step <NUM> may correspond to one of the at least one SMF.

NWDAF may receive TAC information from AMF.

NWDAF may generate analytics based on the information for analytics and the TAC information.

NWDAF may transmit the generated analytics to the SMF that requested the analytics.

NWDAF may receive information for new Analytics from the at least one SMF.

NWDAF may receive new TAC information from the AMF.

NWDAF may create new Analytics based on the information for the new Analytics and the new TAC information.

NWDAF may transmit the new Analytics to the SMF.

Claim 1:
A method for performing communication, performed by a Session Management Function, SMF, comprising:
transmitting (Fig. <NUM>, <NUM>), to a Network Data Analytics Function, NWDAF, a request for Analytics for User Equipment, UE, communication;
wherein the request for Analytics includes Data Network Name, DNN, and Single Network Slice Selection Assistance Information, S-NSSAI,
wherein the request for Analytics includes a request for statistics or prediction for the UE communication,
receiving (Fig. <NUM>, <NUM>), from the NWDAF, an Analytics for the UE communication, based on the request for Analytics;
wherein, based on the request for Analytics including the request for statistics, the received Analytics includes statistics for the UE communication,
wherein, based on the request for Analytics including the request for prediction, the received Analytics includes prediction for the UE communication,
determining (Fig. <NUM>, <NUM>) a value of inactivity timer for a Packet Data Unit, PDU, session based on the received Analytics;
transmitting (Fig. <NUM>, <NUM>), to a User Plane Function, UPF, the value of inactivity timer;
receiving, based on no data transmission in the PDU session corresponding to the DNN and the S-NSSAI for the time of the value of inactivity timer, a message indicating that there is no data transmission in the PDU session for the time of the value of inactivity timer from the UPF; and
deactivating the PDU session based on said message.