Method and apparatus for selecting network in consideration of energy

Abstract

The present disclosure provides a method and apparatus for selecting a network in consideration of energy usage in a wireless communication system. The method performed by a first network entity corresponding to an AMF in a wireless communication system, according to an embodiment of the present disclosure, may comprise the steps of: receiving UE subscription information from a second network entity corresponding to a UDM; receiving, from a UE, a request message for network energy saving (NES); determining NES activation for the UE on the basis of at least one of the UE subscription information and the request message; and transmitting NES-related information to the UE, wherein the request message may include information on whether energy saving is allowed for the UE.

Description

Energy-conscious network selection method and device

[0001] The present disclosure relates to a method and device for selecting a network considering energy usage in a wireless communication system.

[0002] 5G (5th generation) mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in the sub-6GHz frequency band such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band called millimeter wave (mmWave) ('Above 6GHz') such as 28GHz and 39GHz. In addition, for 6G (6th generation) mobile communication technology, which is called the system after 5G communication (Beyond 5G), implementation in the terahertz band (for example, 3 terahertz (3THz) band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and satisfy performance requirements for enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase the transmission distance of radio waves, support for various numerologies (such as operation of multiple subcarrier intervals) and dynamic operation of slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (Bidth Part), new channel coding methods such as LDPC (Low Density Parity Check) codes for large-capacity data transmission and Polar Code for reliable transmission of control information, and L2 pre-processing (L2). Standardization has been made for network slicing, which provides dedicated networks specialized for specific services, and pre-processing.

[0004] Currently, discussions are underway to improve and enhance the initial 5G mobile communication technology in consideration of the services that 5G mobile communication technology was intended to support, and physical layer standardization is in progress for technologies such as V2X (Vehicle-to-Everything) to help autonomous vehicles make driving decisions and increase user convenience based on their own location and status information transmitted by vehicles, NR-U (New Radio Unlicensed) for the purpose of system operation that complies with various regulatory requirements in unlicensed bands, NR terminal low power consumption technology (UE Power Saving), Non-Terrestrial Network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with terrestrial networks is impossible, and Positioning.

[0005] In addition, standardization of wireless interface architecture / protocols is in progress for technologies such as intelligent factories (Industrial Internet of Things, IIoT) to support new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) that provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement technology including Conditional Handover and Dual Active Protocol Stack (DAPS) handover, and 2-step random access (2-step RACH for NR) that simplifies random access procedures. Standardization is also in progress for system architecture / services such as 5G baseline architecture (e.g., Service-based Architecture, Service-based Interface) for grafting Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) that provides services based on the location of the terminal.

[0006] Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices. To this end, new research will be conducted on improving 5G performance and reducing complexity, supporting AI services, supporting metaverse services, and drone communications by utilizing eXtended Reality (XR), Artificial Intelligence (AI), and Machine Learning (ML) to efficiently support Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR).

[0007] In addition, the development of these 5G mobile communication systems includes new waveforms to ensure coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), Array Antenna, and Large Scale Antenna, metamaterial-based lenses and antennas to improve the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), Reconfigurable Intelligent Surface (RIS) technology, as well as full duplex technology to improve the frequency efficiency and system network of 6G mobile communication technology, satellite, AI (Artificial Intelligence) from the design stage and AI-based communication technology that realizes system optimization by internalizing end-to-end AI support functions, and ultra-high-performance communication and computing resources to provide services with complexity that exceeds the limits of terminal computing capabilities. It can serve as a basis for the development of next-generation distributed computing technologies that can be realized by utilizing them.

[0008] Network operators may find themselves in situations where they need to reduce network energy usage, for example, to comply with energy usage regulations or to reduce costs associated with electricity consumption.

[0009] The present disclosure proposes a network selection method and device considering energy usage to reduce network energy usage.

[0010] In accordance with one embodiment of the present disclosure, a method performed by a first network entity corresponding to an access and mobility management function (AMF) in a wireless communication system includes the steps of: receiving user equipment (UE) subscription information from a second network entity corresponding to unified data management (UDM); receiving a request message for network energy saving (NES) from the UE; determining NES activation for the UE based on at least one of the UE subscription information or the request message; and transmitting NES-related information to the UE, wherein the request message may include information on whether energy saving is permitted for the UE.

[0011] According to another embodiment of the present disclosure, a method performed by a user equipment (UE) in a wireless communication system includes the steps of transmitting a request message for network energy saving (NES) to a first network entity corresponding to an access and mobility management function (AMF), and receiving NES-related information from the first network entity, wherein the request message includes information on whether energy saving is permitted for the UE, and whether NES is activated for the UE can be determined based on the request message.

[0012] In another embodiment of the present disclosure, in a wireless communication system, a first network entity corresponding to an access and mobility management function (AMF) includes a transceiver and a control unit, and the control unit is configured to receive user equipment (UE) subscription information from a second network entity corresponding to unified data management (UDM), receive a request message for network energy saving (NES) from the UE, determine NES activation for the UE based on at least one of the UE subscription information and the request message, and transmit NES-related information to the UE, wherein the request message may include information on whether energy saving is permitted for the UE.

[0013] In a wireless communication system according to another embodiment of the present disclosure, a user equipment (UE) includes a transceiver and a control unit, and the control unit is configured to transmit a request message for network energy saving (NES) to a first network entity corresponding to an access and mobility management function (AMF), and to receive NES-related information from the first network entity, wherein the request message includes information on whether energy saving is permitted for the UE, and whether NES is activated for the UE can be determined based on the request message.

[0014] According to one embodiment of the present disclosure, a network operator can achieve network energy saving effects by allowing terminals with energy saving enabled to receive services through network slices that consume less energy.

[0015] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

[0016] FIG. 1 illustrates the structure of a 5G system according to one embodiment of the present disclosure.

[0017] FIG. 2 illustrates a method for providing Allowed NSSAI according to NES (network energy saving) status in a registration procedure according to one embodiment of the present disclosure.

[0018] FIG. 3 illustrates a method for providing Allowed NSSAI in a terminal configuration information update procedure according to a change in NES status according to an embodiment of the present disclosure.

[0019] FIG. 4 illustrates a method for deriving and providing NSAG priority by considering NES status in a registration procedure according to one embodiment of the present disclosure.

[0020] FIG. 5 illustrates a method for providing NSAG priority in a terminal configuration information update procedure according to a change in NES status according to an embodiment of the present disclosure.

[0021] FIG. 6 illustrates a method for providing an Enhanced UE route selection policy (URSP) rule in a terminal registration procedure according to one embodiment of the present disclosure.

[0022] FIG. 7 illustrates a method for transmitting NES status for a UE for which an Enhanced URSP rule is set in a terminal configuration update procedure according to an embodiment of the present disclosure.

[0023] FIG. 8 is a block diagram illustrating the structure of a terminal according to an embodiment of the present disclosure.

[0024] FIG. 9 is a diagram illustrating the structure of a network entity performing a network function according to one embodiment of the present disclosure.

[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0026] In describing the embodiments, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to convey the gist of the present disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0027] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0028] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, a detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and may vary depending on the intention or custom of the user or operator. Therefore, their definitions should be made based on the contents throughout the specification.

[0029] In explaining the embodiments of the present disclosure, the main target is New Radio (NR), which is a wireless access network, and the core network, packet core 5G System, or 5G Core Network, or NG Core (Next Generation Core) in the 5G mobile communication standard specified by 3GPP (3rd Generation Partnership Project), a mobile communication standard standardization organization. However, the main gist of the present disclosure can be applied to other communication systems with similar technical backgrounds with slight modifications within a range that does not significantly deviate from the scope of the present disclosure, and this will be possible at the discretion of a person skilled in the art of the present disclosure.

[0030] For convenience of explanation, some terms and names defined in the 3GPP standards (standards for 5G, NR, LTE, or similar systems) may be used below. However, the present disclosure is not limited by these terms and names, and can be equally applied to systems conforming to other standards.

[0031] Hereinafter, terms used in this disclosure to identify connection nodes, terms referring to network entities, terms referring to messages, terms referring to interfaces between network entities, terms referring to various identification information, etc. are provided as examples for convenience of explanation. Therefore, the present disclosure is not limited to the terms used in this disclosure, and other terms referring to objects with equivalent technical meanings may be used.

[0032] Hereinafter, the base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station.

[0033] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0034] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0035] The term '~ unit' used in the embodiments of the present disclosure means a software or hardware component such as an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit), and the '~ unit' performs certain roles. However, the '~ unit' is not limited to software or hardware. The '~ unit' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Thus, as an example, the '~ unit' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, the components and '~parts' may be implemented to play one or more central processing units (CPUs) within the device or secure multimedia card. In addition, in the embodiment, the '~part' may include one or more processors.

[0036] FIG. 1 illustrates the structure of a 5G system according to one embodiment of the present disclosure.

[0037] A 5G mobile communication network may be composed of a 5G UE (user equipment, terminal) (100), a 5G RAN (radio access network, base station), gNB (5G nodeB), eNB (evolved nodeB, etc.) (110), and a 5G core network. The 5G core network may be composed of NFs such as an AMF (access and mobility management function) (120) that provides a mobility management function of the UE, a SMF (session management function) (135) that provides a session management function, an UPF (user plane function) (130) that performs a data transfer role, a PCF (policy control function) (140) that provides a policy control function, a UDM (unified data management) (145) that provides a data management function such as subscriber data and policy control data, and a UDR (unified data repository) that stores data of various network functions (NFs). The 5G core network may be composed of NFs such as an NSSF (network slice selection function) (160), a NWDAF (network data analytic function) It can be configured to include additional NFs such as (151), AF (application function) (170), DN (data network) (175), NSACF (network slice admission control function) (180).

[0038] In the 3GPP system, a conceptual link connecting NFs within a 5G system is defined as a reference point. The following illustrates a reference point included in the 5G system architecture depicted in Figure 1.

[0039] - N1: Reference point between UE and AMF

[0040] - N2: Reference point between (R)AN and AMF

[0041] - N3: Reference point between (R)AN and UPF

[0042] - N4: Reference point between SMF and UPF

[0043] - N5: Reference point between PCF and AF

[0044] - N6: Reference point between UPF and DN

[0045] - N7: Reference point between SMF and PCF

[0046] - N8: Reference point between UDM and AMF

[0047] - N9: Reference point between two core UPFs

[0048] - N10: Reference point between UDM and SMF

[0049] - N11: Reference point between AMF and SMF

[0050] - N12: Reference point between AMF and AUSF (authentication server function)

[0051] - N13: Reference points between UDM and AUSF

[0052] - N14: Reference point between two AMFs

[0053] - N15: Reference point between PCF and AMF for non-roaming scenarios, reference point between PCF and AMF in visited network for roaming scenarios.

[0054] In 5G systems, network slicing technology refers to the technology and architecture that enables multiple virtualized, independent, logical networks within a single physical network. Network operators provide services by configuring virtual end-to-end networks called network slices to meet the specialized requirements of services / applications. At this time, network slices are identified by an identifier called single-network slice selection assistance information (S-NSSAI). During the UE registration procedure (e.g., UE registration procedure), the network transmits a set of allowed slices (e.g., allowed NSSAI(s)) to the UE, and the UE transmits and receives application data through a PDU (protocol data unit) session created through one of these S-NSSAIs (i.e., network slices).

[0055] FIG. 2 illustrates a method for providing Allowed NSSAI according to a network energy saving (NES) status in a registration procedure according to one embodiment of the present disclosure.

[0056] At this time, the NES status (or energy mode) may be set to indicate (indicate) that two stages (e.g., activated, deactivated) or two or more stages (e.g., normal mode, low energy saving, high energy saving mode, etc.) indicating the current energy saving degree for the UE are used, for example. For example, when the NES status of the UE is deactivated (or normal mode), it means that network energy saving is not performed for the UE.

[0057] In step 201, the terminal may transmit an AN (access network) message containing a registration request message to the RAN. The message may include at least one of the following information:

[0058] - UE ID: The identifier information of the terminal. If the terminal has an available 5G-GUTI (5G globally unique temporary identifier) ​​allocated from the network, it may include this. If not, the subscriber concealed identifier (SUCI) may be included.

[0059] - Requested NSSAI: May contain S-NSSAI(s) information requested by the UE;

[0060] - ES (energy saving) Allowed (or ES Non-Allowed indication): Indicates an indication to allow ES (or not allow ES). The UE may change the ES status information to Allowed if it receives an input from the user of the UE to allow NES, or if the UE has information to allow NES stored as configuration information. The UE may include an ES Allowed or ES non-Allowed indication in its ES status information;

[0061] - Time: This may include time information (such as a period or duration) that allows energy-saving operations for the terminal. For example, it may indicate a specific time of day (such as 1 am to 5 am); or

[0062] - UE 5G MM (mobility management) capability: This indicates information including the functions supported by the terminal. For example, it may include support for NSAG (Network Slice Access Stratum Group) (i.e., terminals that support cell reselection based on network slice groups). In addition, for example, support for NES (Support of NES) may be included.

[0063] In step 202, the RAN may transmit the registration request message received from the terminal to the AMF.

[0064] In step 203a, the AMF may send a message requesting subscription information of the UE to the UDM (e.g., Nudm_SDM_Get request message), and in step 203b, the AMF may receive a response message containing subscription information of the UE from the UDM. The subscription information of the UE received from the UDM may include ES Allowed indication, time information, and / or subscribed S-NSSAI(s). The subscribed S-NSSAI(s) may include information on whether a default S-NSSAI is present for each S-NSSAI.

[0065] In step 204, the AMF may determine whether to perform NES activation for the corresponding terminal if the registration request message received in step 202 includes an ES Allowed indication or if the UE subscription information received in step 203b includes an ES Allowed indication. If the information received in step 202 or step 203b includes time information for the NES together with the ES Allowed indication, the AMF may perform NES activation for the corresponding terminal within the time band corresponding to the time information.

[0066] When the AMF decides to activate the NES, it may store information indicating that the NES has been activated for the corresponding terminal (e.g., an NES status set to 'activated') internally or in the UE context in the AMF. For a terminal with the NES activated, the 5G system may perform one or more of various actions to reduce the energy consumed to provide services to the terminal(s).

[0067] In step 205, the AMF may determine the Allowed NSSAI for the UE by considering one or more of NES activation for the UE (i.e., NES status), Subscribed S-NSSAI(s), and Requested NSSAI. For example, for a UE with NES activation, the AMF may include one or more of the S-NSSAI(s) with lower average energy consumption (or average energy efficiency) per S-NSSAI in the Allowed NSSAI to be transmitted to the UE, or one or more of the S-NSSAI(s) with higher energy efficiency. Alternatively, the AMF may include only the default subscribed S-NSSAI(s) in the Allowed NSSAI for the UE by considering whether NES is activated for the UE.

[0068] If the AMF does not directly determine the Allowed NSSAI in step 205, then in step 206a, the AMF may send a request message (e.g., Nnssf_NSSelection_Get request message) to the NSSF including the following information to obtain the Allowed NSSAI. For example, if there is an available NSSF, the AMF may send the request message (e.g., Nnssf_NSSelection_Get request message) to the NSSF.

[0069] For example, a request message (e.g., Nnssf_NSSelection_Get request message) may include NES status, Subscribed S-NSSAI(s), or Requested NSSAI.

[0070] In step 206b, if the message received from the AMF includes an NES status, the NSSF may determine an Allowed NSSAI for the UE by considering whether the UE is NES-enabled (i.e., the NES status), one or more of the Subscribed S-NSSAI(s), and the Requested NSSAI. For example, for a UE with NES-enabled, the NSSF may include one or more of the S-NSSAI(s) with lower average energy consumption (or average energy efficiency) per S-NSSAI in the Allowed NSSAI to be transmitted to the UE, or one or more of the S-NSSAI(s) with higher energy efficiency. Alternatively, if the NES status indicates activation, the NSSF may include only the default subscribed S-NSSAI(s) in the Allowed NSSAI for the UE. When the NES status indicates disabled, NSSF may include S-NSSAI(s) included in Subscribed S-NSSAI(s) among Requested NSSAI(s) in Allowed NSSAI. NSSF may send a response message (e.g., Nnssf_NSSelection_Get response message) to AMF. The response message (e.g., Nnssf_NSSelection_Get response message) may include Allowed NSSAI and / or Configured NSSAI.

[0071] In some cases, steps 206a and 206b may be omitted.

[0072] At step 207, the AMF may send a registration accept message to the RAN. For example, the registration accept message may include Allowed NSSAI.

[0073] At step 208, the RAN may transmit a message received from the AMF (e.g., a registration acceptance message) to the UE.

[0074] The UE may store the Allowed NSSAI if the received message includes the Allowed NSSAI. The UE may perform a PDU Session Establishment request (S-NSSAI) or transmit / receive data only through the S-NSSAI(s) included in the Allowed NSSAI (for example, the PDU Session Establishment request may include only one of the S-NSSAIs included in the Allowed NSSAI).

[0075] FIG. 3 illustrates a method for providing Allowed NSSAI in a terminal configuration information update procedure according to a change in NES status according to an embodiment of the present disclosure.

[0076] In step 301, if the AMF receives a message indicating that NES is required (or a warning message indicating that network energy usage is too high) from at least one of OAM (operation, administration, maintenance), PCF, NWDAF, NSSF, and RAN, or if the AMF determines that NES is required (e.g., by considering network energy consumption conditions), the AMF may determine the UE(s) on which NES is to be activated. If the AMF receives a message indicating that NES is required (or a warning message indicating that network energy usage is too high in the RAN) from the RAN, the AMF may consider UEs connected to the network via the RAN as targets for performing NES activation.

[0077] The AMF can select UEs to perform NES activation. For example, the AMF can select one or more UEs among those UEs that include an ES Allowed indication in their subscription information or among UEs that have provided an ES Allowed indication. If the message received from the UE during the subscription information or registration procedure includes time information for the NES along with the ES Allowed indication, the AMF can perform NES activation for the UE within the time band corresponding to the time information.

[0078] When the AMF determines to activate the NES, it may store information indicating that the NES has been activated for the corresponding terminal (e.g., the NES status set to 'activated') internally or in the UE Context in the AMF. For a terminal with the NES activated, the 5G system may perform one or more of various actions to reduce the energy consumed to provide services to the terminal(s).

[0079] In step 302, the AMF may determine the Allowed NSSAI for the UE by considering whether the NES is enabled for the UE (i.e., NES status), one or more of the Subscribed S-NSSAI(s), or the Requested NSSAI. For example, for a UE with NES enabled, the AMF may include one or more of the S-NSSAI(s) with lower average energy consumption (or average energy efficiency) per S-NSSAI in the Allowed NSSAI to be transmitted to the UE, or one or more of the S-NSSAI(s) with higher energy efficiency. Alternatively, the AMF may include only the default subscribed S-NSSAI(s) in the Allowed NSSAI for the UE by considering whether the NES is enabled for the UE.

[0080] If the AMF does not directly determine the Allowed NSSAI in step 302, the AMF may send a request message (e.g., Nnssf_NSSelection_Get request message) to the NSSF to obtain the Allowed NSSAI in step 303a. For example, if there is an available NSSF, the AMF may send the Nnssf_NSSelection_Get request message to the NSSF.

[0081] For example, the above request message (e.g., Nnssf_NSSelection_Get request message) may include NES status, Subscribed S-NSSAI(s), or Requested NSSAI.

[0082] In step 303b, if the message received from the AMF includes an NES status, the NSSF may determine an Allowed NSSAI for the UE by considering whether the UE is NES-enabled (i.e., the NES status), one or more of the Subscribed S-NSSAI(s), and the Requested NSSAI. For example, for a UE with NES-enabled, the NSSF may include one or more of the S-NSSAI(s) with lower average energy consumption (or average energy efficiency) by considering the average energy consumption (or average energy efficiency) per S-NSSAI in the Allowed NSSAI to be transmitted to the UE, or one or more of the S-NSSAI(s) with higher energy efficiency. Alternatively, the NSSF may include only the default subscribed S-NSSAI(s) in the Allowed NSSAI for the UE if the NES status indicates activation. When the NES status changes from enabled to disabled, NSSF may include one or more of the S-NSSAI(s) included in the Subscribed S-NSSAI(s) in the Allowed NSSAI(s). NSSF may send a response message (e.g., Nnssf_NSSelection_Get response message) to AMF. The response message (e.g., Nnssf_NSSelection_Get response message) may include the Allowed NSSAI and / or the Configured NSSAI.

[0083] In some cases, steps 303a and 303b may be omitted.

[0084] At step 304, the AMF may send a UE configuration update message to the RAN. For example, the UE configuration update message may include Allowed NSSAI.

[0085] At step 305, the RAN may transmit a message received from the AMF (e.g., UE configuration update message) to the UE.

[0086] The UE may store the Allowed NSSAI if it contains the Allowed NSSAI in the received message (e.g., UE configuration update message). The UE may perform a PDU Session Establishment request or transmit / receive data only through the S-NSSAI(s) contained in the Allowed NSSAI (e.g., a PDU Session Establishment request may contain only one of the S-NSSAIs contained in the Allowed NSSAI).

[0087] FIG. 4 illustrates a method for deriving and providing NSAG priorities by considering NES status in a registration procedure according to one embodiment of the present disclosure.

[0088] In step 401, the terminal may transmit an AN (access network) message containing a registration request message to the RAN. The message may include at least one of the following information:

[0089] - UE ID: Terminal identifier information, which includes available 5G-GUTI allocated to the terminal from the network if available, and if not, SUCI may be included;

[0090] - Requested NSSAI: May contain S-NSSAI(s) information requested by the UE;

[0091] - ES (energy saving) Allowed (or ES Non-Allowed indication): Indicates an indication allowing energy saving (or not allowing it). If the UE receives an input allowing NES from the user of the UE, or if the UE has information allowing NES stored as configuration information, the UE can change the ES status information to Allowed. The UE can include ES Allowed or ES non-Allowed in the registration request message according to its ES status information;

[0092] - time: May include time information (such as a period or duration) that allows energy saving operations for the terminal. For example, it may indicate a specific time of day (such as 1 am to 5 am); or

[0093] - UE 5G MM Capability: This indicates information about the capabilities supported by the terminal. For example, this may include support for NSAG (i.e., terminals that support cell reselection based on network slice groups). Additionally, this may include support for NES (Network Efficiency Service).

[0094] At step 402, the RAN may transmit the registration request message received from the terminal to the AMF.

[0095] In step 403a, the AMF may send a message requesting subscription information of the UE to the UDM (e.g., a Nudm_SDM_Get request message), and in step 403b, may receive a response message containing subscription information of the UE from the UDM. The subscription information of the UE received from the UDM may include ES Allowed indication, time information, and / or Subscribed S-NSSAI(s). The Subscribed S-NSSAI(s) may include information on whether each S-NSSAI is a default S-NSSAI.

[0096] In step 404, the AMF may determine whether to perform NES activation for the corresponding terminal if the registration request message received in step 402 includes an ES Allowed indication or if the UE subscription information received in step 403b includes an ES Allowed indication. If the information received in step 402 or step 403b includes time information for the NES together with the ES Allowed indication, the AMF may perform NES activation for the corresponding terminal within the time band corresponding to the time information.

[0097] When the AMF determines to activate the NES, it may store information indicating that the NES has been activated for the corresponding terminal (e.g., the NES status set to 'activated') internally or in the UE Context in the AMF. For a terminal with the NES activated, the 5G system may perform one or more of various actions to reduce the energy consumed to provide services to the terminal(s).

[0098] In step 405, if the AMF determines to activate NES for the UE, and if the UE is a terminal that supports NSAG, the AMF may determine the NSAG priority to be transmitted to the UE by considering whether the UE has NES activated and the energy consumption (or energy efficiency) for the S-NSSAI(s) associated with the NSAG ID.

[0099] NSAG priority is one or more<NSAG ID, NSAG priority> It can be composed of pairs. For example, the NSAG priority already provided to the UE<NSAG_1, High priority> ,<NSAG_2, low priority> can be configured in the form of. If the AMF decides to activate NES for the UE, the AMF can reconfigure the NSAG priority when the S-NSSAI(s) corresponding to NSAG_2 consume low energy and the S-NSSAI(s) corresponding to NSAG_1 consume high energy. That is, the priority for NSAG_1 can be changed to low priority and the priority for NSAG_2 can be changed to high priority. That is, the AMF can set a high priority for the NSAG ID associated with the S-NSSAI(s) consuming low energy in the NSAG priority to be provided to the NES-activated UE.

[0100] Alternatively, if the UE MM Capability received from the UE includes Support of NES, the AMF may provide the UE with the NES status (e.g., NES activated, NES deactivated) along with the NSAG priority (i.e., Enhanced NSAG priority) according to the type of NES status (or Energy Mode). For example, the Enhanced NSAG priority provided to the UE may include the NES status that the UE can use when NES is activated.<NSAG id, priority> When the NES is disabled with a pair(s), the terminal can be used<NSAG id, priority> Pair(s) may be included. The terminal may use when the NES is activated.<NSAG id, priority> Pair(s) may be configured with a higher priority for NSAG ids associated with S-NSSAI(s) with lower energy consumption (or higher energy efficiency) than for NSAG ids associated with S-NSSAI(s) with higher energy consumption. This allows the terminal to use the NSAG ids when the NES is disabled.<NSAG id, priority> The pair(s) may be determined by considering one or more of the UE's Allowed NSSAI, Configured NSSAI, and Subscribed S-NSSAI(s).

[0101] At step 406, the AMF may send a registration accept message to the RAN. For example, the registration accept message may include at least one of the following information:

[0102] - NSAG Information: Along with the NSAG priority, one or more NSAG ID(s) may contain associated S-NSSAI(s) information per NSAG ID; or

[0103] - Enhanced NSAG information, NES status: If the AMF decides to provide the terminal with NSAG priority based on NES status (i.e., enhanced NSAG priority), the NES status (e.g., NES activated or NES deactivated) may be included along with the Enhanced NSAG information instead of the NSAG information. The Enhanced NSAG information may include the associated S-NSSAI(s) information for each NSAG ID, along with the Enhanced NSAG priority.

[0104] In step 407, the RAN may transmit the registration accept message received from the AMF to the UE. If the UE receives the NSAG priority, the UE may delete the existing NSAG priority and store the new NSAG priority. If the UE receives the Enhanced NSAG priority, the UE may delete the existing NSAG priority and store the Enhanced NSAG priority. Additionally, if the UE receives the NES status, the UE may store the NES status (e.g., 'activated' or 'deactivated').

[0105] At step 408, the UE may reselect a cell supporting a slice with low energy consumption based on the received NSAG priority (or Enhanced Priority).

[0106] If a UE supporting NES receives an NES status set to Enhanced NSAG priority, activated, the UE can perform cell reselection using the NSAG priority corresponding to NES activated within the Enhanced NSAG priority.

[0107] If the UE receives an NES status set to Enhanced NSAG priority, deactivated, the UE can perform cell reselection using the NSAG priority corresponding to NES deactivated within the Enhanced NSAG priority.

[0108] If the UE has already received Enhanced NSAG priority and the registration accept message contains only NES status, the UE can perform cell reselection using one of the NSAG priority sets included in the already received Enhanced NSAG priority according to the NES status.

[0109] FIG. 5 illustrates a method for providing NSAG priority in a terminal configuration information update procedure according to a change in NES status according to an embodiment of the present disclosure.

[0110] In step 501, the AMF may determine that NES is required based on its own configuration information, information received from the NWDAF, signaling from the OAM, or signaling from the PCF. If the AMF determines that NES is required, it may determine the UE(s) for which NES activation is to be performed. For example, the AMF may decide to perform NES activation (or deactivation) for one or more of the UE(s) that provided the ES Allowed indication and additionally time information (i.e., time information allowing activation of Energy Saving) during the registration procedure, or the UE(s) for which the ES Allowed indication is included in the subscription information. The AMF may change the NES status to 'activated' for the UE(s) for which it decided to activate NES. Alternatively, the AMF may decide to perform NES deactivation for the UE(s) for which NES is being applied based on its own configuration information, information received from the NWDAF, signaling from the OAM, or signaling from the PCF. AMF may change the NES status to 'deactivated' for UE(s) that have decided to deactivate the NES or delete the NES status itself.

[0111] AMF may perform one or more of a variety of actions to save energy for UEs whose NES status indicates 'activated' (i.e., UEs with NES activation).

[0112] In step 502, the AMF may decide to update the Allowed NSSAI previously provided to the UE (i.e., send a new Allowed NSSAI to the UE) considering whether the NES status for the UE is activated. At this time, the AMF may exclude some S-NSSAI(s) from the Allowed NSSAI if the NES status for the UE is changed to 'activated'. For example, the AMF may exclude or replace an S-NSSAI included in the Allowed S-NSSAI with another S-NSSAI considering the average energy consumption (or average energy efficiency) per S-NSSAI included in the existing Allowed NSSAI for the NES-activated UE. For example, the AMF may exclude S-NSSAI(s) with high energy usage (e.g., S-NSSAI requiring high frequency band and high speed) from the Allowed NSSAI. Alternatively, the AMF may replace S-NSSAI(s) with high energy usage (e.g., S-NSSAI requiring high frequency band and high speed) with S-NSSAI(s) with low energy usage if the UE supports Network Slice Replacement. That is, the AMF may include S-NSSAIs with low energy usage in Allowed NSSAI and exclude S-NSSAIs with high energy usage.

[0113] Alternatively, AMF may include only the default subscribed S-NSSAI(s) in the Allowed NSSAI for the UE, taking into account whether NES is enabled for the UE.

[0114] If AMF decides to activate NES for the UE, and if the UE supports NSAG, AMF may decide the NSAG priority to be transmitted to the UE by considering whether NES is activated for the UE and the energy consumption (or energy efficiency) for the S-NSSAI(s) associated with the NSAG ID.

[0115] NSAG priority is one or more<NSAG ID, NSAG priority> It can be composed of pairs. For example, the NSAG priority already provided to the UE<NSAG_1, High priority> ,<NSAG_2, low priority> can be configured in the form of. If the AMF decides to activate NES for the UE, the AMF can reconfigure the NSAG priority when the S-NSSAI(s) corresponding to NSAG_2 consume low energy and the S-NSSAI(s) corresponding to NSAG_1 consume high energy. That is, the priority for NSAG_1 can be changed to low priority and the priority for NSAG_2 can be changed to high priority. That is, the AMF can set a high priority for the NSAG ID associated with the S-NSSAI(s) consuming low energy in the NSAG priority to be provided to the NES-activated UE.

[0116] Alternatively, if the AMF receives an ES Allowed indication from the UE, it may provide the UE with the NES status (e.g., NES activated, NES deactivated) along with the NSAG priority (i.e., Enhanced NSAG priority) depending on whether the NES is activated. For example, the Enhanced NSAG priority provided to the UE may include the UE's ability to use the NES when it is activated.<NSAG id, priority> When the NES is disabled with a pair(s), the terminal can be used<NSAG id, priority> Pair(s) may be included. The terminal may use when the NES is activated.<NSAG id, priority> Pair(s) may be configured with a higher priority for NSAG ids associated with S-NSSAI(s) with lower energy consumption (or higher energy efficiency) than for NSAG ids associated with S-NSSAI(s) with higher energy consumption. This allows the terminal to use the NSAG ids when the NES is disabled.<NSAG id, priority> The pair(s) may be determined by considering one or more of the UE's Allowed NSSAI, Configured NSSAI, and Subscribed S-NSSAI(s).

[0117] In step 503, the AMF may send a UE configuration update message to the RAN. The UE configuration update message may include at least one of the following information:

[0118] - Allowed NSSAI: May contain network slice identifier(s) allowed to the terminal;

[0119] - NSAG information: along with NSAG priority, one or more NSAG ID(s) may contain associated S-NSSAI(s) information per NSAG ID; or

[0120] - Enhanced NSAG information, NES status: If the AMF decides to provide the terminal with NSAG priority based on NES status (i.e., enhanced NSAG priority), the NES status (e.g., NES activated or NES deactivated) may be included together with the Enhanced NSAG information instead of the NSAG information. The Enhanced NSAG information may include the associated S-NSSAI(s) information for each NSAG ID, along with the Enhanced NSAG priority.

[0121] At step 504, the RAN may transmit the UE configuration update message received from the AMF to the UE.

[0122] If the UE receives a new NSAG priority, the UE can delete the existing NSAG priority and store the new NSAG priority. Based on the new NSAG priority, the UE can reselect a cell that supports a slice with low energy consumption (cell reselection).

[0123] If the UE receives an NES status set to Enhanced NSAG priority, activated, the UE can perform cell reselection using the NSAG priority corresponding to NES activated within the Enhanced NSAG priority.

[0124] If the UE receives an NES status set to Enhanced NSAG priority, deactivated, the UE can perform cell reselection using the NSAG priority corresponding to NES deactivated within the Enhanced NSAG priority.

[0125] If the UE has already received Enhanced NSAG priority and the registration accept message contains only NES status, the UE can perform cell reselection using one of the NSAG priority sets included in the already received Enhanced NSAG priority according to the NES status.

[0126] FIG. 6 illustrates a method for providing an Enhanced UE route selection policy (URSP) rule in a terminal registration procedure according to one embodiment of the present disclosure.

[0127] In step 601, the terminal may transmit an AN (access network) message containing a registration request message to the RAN. The message may include at least one of the following information:

[0128] - UE ID: Terminal identifier information, which includes available 5G-GUTI allocated to the terminal from the network if available, and if not, SUCI may be included;

[0129] - Requested NSSAI: May contain S-NSSAI(s) information requested by the UE;

[0130] - UE 5G MM Capability: Indicates information including the functions supported by the terminal. For example, Support of NES may be included; or

[0131] - time: May contain time information (such as a period or duration) that allows energy saving operations for the terminal. For example, it may indicate a specific time of day (e.g., 1 am to 5 am).

[0132] In step 602, the RAN may transmit the registration request message received from the terminal to the AMF.

[0133] In step 603a, the AMF may send a message to the PCF to request a UE Policy (e.g., an Npcf_UEPolicyControl Create message). The message may include identifier information of the UE (e.g., a subscription permanent identifier (SUPI)) and, if the message received by the AMF from the UE in step 602 included Support of NES, Support of NES.

[0134] At step 603b, PCF may send a response message (e.g., Npcf_UEPolicyControl Create response message) to AMF.

[0135] In step 604, the PCF may include URSP rule(s) (i.e., enhanced URSP rule(s)) having S-NSSAI per NES status of the UE (or per Energy Mode of the UE) in the UE Policy Container transmitted to the UE if the UE supports NES (i.e., Support of NES is received in step 603a). A conventional URSP rule may include, for example, a pair of Traffic Descriptor (TD) representing traffic (e.g., a connection capability including a traffic category) and a route selection descriptor (RSD) component (e.g., an S-NSSAI) to be used for the corresponding TD. An enhanced URSP rule may consist of, for example, a Traffic Descriptor (TD) representing traffic (e.g., a connection capability including a traffic category) and one or more RSD components to be used for the corresponding TD. For example, an Enhanced URSP rule may include an S-NSSAI to be used when the NES status of a UE is deactivated for a TD, and an S-NSSAI to be used when the NES status of the UE is set to activated. In this case, the S-NSSAI for the case where the NES status is set to activated may be configured with one or more of the S-NSSAIs configured to consume less network energy (i.e., a slice in which NFs within the network slice are set to a mode in which they consume less energy). The S-NSSAI for the case where the NES status is set to deactivated may be configured with one or more of the S-NSSAIs suitable for the corresponding TD.

[0136] If the UE supports NES (i.e., if Support of NES is received in step 3a), the PCF may determine the NES status (or Energy Mode) of the UE and include the NES status in the UE Policy container transmitted to the UE. If the NES status is determined to be disabled, the NES status may not be included.

[0137] At step 605, PCF may include the UE Policy Container in a message sent to AMF (e.g., Npcf_UEPolicyControlNotify message) and send it to AMF.

[0138] In step 606, the AMF may include the message received from the PCF in an N2 message (NAS message) and transmit it to the RAN. The N2 message may include a UE Policy Container.

[0139] In step 607, the RAN may transmit to the UE a non-access stratum (NAS) message included in a message received from the AMF, in an access network (AN) message.

[0140] A UE supporting NES can store the received UE Policy Container if it contains Enhanced URSP rule(s). The UE can store the NES status if it contains the UE Policy Container. If the UE Policy Container contains Enhanced URSP rule(s) but does not contain the NES status, the UE determines the NES status as deactivated and stores its NES status as deactivated.

[0141] At step 608, the remaining terminal registration procedures can be performed.

[0142] FIG. 7 illustrates a method for transmitting NES status for a UE for which an Enhanced URSP rule is set in a terminal configuration update procedure according to an embodiment of the present disclosure.

[0143] At step 701, the PCF may receive a notification message from the OAM / NWDAF that the NES has changed to a required state or a notification message that the NES has changed to an unneeded state.

[0144] In step 702, the PCF may decide to activate NES status for one or more of the UEs supporting NES (or deactivate NES status for UEs that are already NES-enabled) based on the notification message received in step 701 or according to operator policy.

[0145] If the NES status (or Energy Mode) of the UE changes, the PCF may include the NES status in the UE Policy container transmitted to the UE. Alternatively, if the NES status changes to disabled, the PCF may not include the NES status in the UE Policy container.

[0146] The PCF may include URSP rule(s) (i.e., enhanced URSP rule(s)) with S-NSSAIs per NES status of the UE (or per Energy Mode of the UE) in the UE Policy Container sent to the UE, if the UE supports NES and has not yet received an enhanced UE Policy container. A traditional URSP rule may, for example, include a pair of TDs representing traffic (e.g., a connection capability including a traffic category) and an RSD component to be used for the TD (e.g., an S-NSSAI). An enhanced URSP rule may, for example, include a TD representing traffic (e.g., a connection capability including a traffic category) and one or more RSD components to be used for the TD. For example, an enhanced URSP rule may include an S-NSSAI to be used when the NES status of the UE is deactivated for one TD, and an S-NSSAI to be used when the NES status of the UE is set to activated for one TD. At this time, the S-NSSAI for the case where the NES status is set to activated may be configured with one or more of the S-NSSAIs set to consume less network energy (i.e., a slice in which NFs within the network slice are set to a mode in which they consume less energy). The S-NSSAI for the case where the NES status is set to deactivated may be configured with one or more of the S-NSSAIs suitable for the corresponding TD.

[0147] If the PCF supports NES and the UE has already received an enhanced UE Policy container, the PCF may not include the Enhanced URSP rule(s) in the UE Policy Container.

[0148] In step 703, PCF may send the UE Policy Container to AMF by including it in a message (e.g., Npcf_UEPolicyControlNotify message).

[0149] At step 704, the AMF may include the message received from the PCF in an N2 message (NAS message) and transmit it to the RAN.

[0150] In step 705, the RAN may include the NAS message included in the message received from the AMF in an AN message and transmit it to the UE.

[0151] A UE supporting NES can store the received UE Policy Container if it contains Enhanced URSP rule(s). The UE can store the NES status if it contains the UE Policy Container. If the UE Policy Container contains Enhanced URSP rule(s) but does not contain the NES status, the UE determines the NES status as deactivated and stores its NES status as deactivated.

[0152] The sequence of operations in FIGS. 2 through 7 may be changed as needed. Furthermore, some operations in FIGS. 2 through 7 may be omitted or two or more steps may be combined and performed. Furthermore, some operations in different drawings may be combined and performed.

[0153] The methods and / or embodiments proposed in this disclosure can be performed by the terminal of FIG. 8 and the network entity of FIG. 9.

[0154] FIG. 8 is a block diagram illustrating the structure of a terminal according to one embodiment of the present disclosure. Of course, the present invention is not limited to the above example, and the terminal may include fewer or more components than those illustrated in FIG. 8.

[0155] Referring to FIG. 8, the terminal may include a transceiver (810), a control unit (820), and a storage unit (830). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor. The transceiver (810) may transmit and receive signals with other network entities. The transceiver (810) may receive system information from a base station, for example, and may receive a synchronization signal or a reference signal. The control unit (820) may control the overall operation of the terminal according to the embodiment proposed in the present disclosure. For example, the control unit (820) may control the signal flow between each block to perform operations according to the flowchart described above. The storage unit (830) stores data such as a basic program, an application program, and setting information for the operation of the terminal. The storage unit (830) may store at least one of information transmitted and received through the transceiver (810) and information generated through the control unit (820). The storage unit (830) may be composed of a storage medium or a combination of storage media, such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD. In addition, the storage unit (830) may be composed of a plurality of memories.

[0156] FIG. 9 is a diagram illustrating the structure of a network entity performing a network function according to one embodiment of the present disclosure. For example, the network entity of FIG. 9 may be a node of a network. For example, the network entity of FIG. 9 may be one of the RAN, AMF, SMF, PCF, NWDAF, NSSF, UDM, or OAM described above through embodiments of the present disclosure.

[0157] Referring to FIG. 9, a network entity performing a network function may include a transceiver (910), a control unit (920), and a storage unit (930). In the present invention, the control unit may be defined as a circuit or an application-specific integrated circuit or at least one processor.

[0158] The transceiver (910) can transmit and receive signals with other network entities. For example, the transceiver (910) can transmit and receive signals or messages with the AMF, a network entity that manages access and mobility of a terminal to an access network.

[0159] The control unit (920) can control the overall operation of a network entity performing network functions according to the embodiments proposed in the present invention. For example, the control unit (920) can control the signal flow between each block to perform operations according to the flowchart described above.

[0160] The storage unit (930) can store at least one of the information transmitted and received through the transmission and reception unit (910) and the information generated through the control unit (920).

[0161] Meanwhile, the order of description in the drawings illustrating the method of the present disclosure does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel. Alternatively, the drawings illustrating the method of the present disclosure may omit some components and include only some components, as long as it does not harm the essence of the present disclosure.

[0162] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are merely specific examples to easily explain the technical contents of the present disclosure and help understand the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art to which the present disclosure pertains that other modified examples are possible based on the technical scope of the present disclosure. In addition, each of the above embodiments can be combined and operated with each other as needed. For example, all embodiments of the present invention can be operated with base stations and terminals by combining parts with each other.

Claims

1. A method performed by a first network entity corresponding to an access and mobility management function (AMF) in a wireless communication system, A step of receiving UE (user equipment) subscription information from a second network entity corresponding to UDM (unified data management); A step of receiving a request message for network energy saving (NES) from a UE; determining NES activation for the UE based on at least one of the UE subscription information or the request message; and Comprising a step of transmitting NES related information to the UE, A method wherein the request message includes information on whether energy saving is allowed for the UE.

2. In paragraph 1, A method characterized in that NES activation is determined for the UE for which energy saving is allowed based on information on whether the energy saving is allowed.

3. In paragraph 1, The above UE subscription information includes information on whether energy saving is allowed for each UE and information on the time during which energy saving is allowed for each UE. One or more UEs to which NES activation is applied are determined based on the information on whether energy saving is allowed for each UE, and A method characterized in that NES activation is applied to said one or more UEs in a time band identified based on information about said time.

4. In paragraph 1, A step of determining a network slice access stratum group (NSAG) priority for the UE; and A method further comprising the step of transmitting information about the determined NSAG priority to the UE.

5. In paragraph 4, The above NSAG priority is set by NES status, A method characterized in that the information about the NSAG priority includes the NSAG priority and the NES status.

6. In paragraph 1, A method in which the above NES-related information includes Allowed NSSAI (network slice selection assistance information).

7. In paragraph 1, Further comprising a step of receiving URSP (UE route selection policy) rules for each NES state of one or more UEs from a third entity corresponding to PCF (policy control function), A method characterized in that the above URSP rule includes a single-network slice selection assistance information (S-NSSAI) to be used when the NES state is disabled for one traffic descriptor and an S-NSSAI to be used when the NES state is enabled for the one traffic descriptor.

8. A method performed by a UE (user equipment) in a wireless communication system, A step of transmitting a request message for network energy saving (NES) to a first network entity corresponding to an access and mobility management function (AMF); and Comprising a step of receiving NES related information from the first network entity, The above request message includes information on whether energy saving is allowed for the UE, and A method wherein whether to activate NES for the UE is determined based on the request message.

9. In paragraph 8, The above request message further includes information about the time during which energy saving is allowed for the UE and a UE identifier, A method characterized in that NES activation for the UE is applied in a time band identified based on information about the time.

10. In paragraph 8, A method characterized in that the above NES-related information includes a network slice access stratum group (NSAG) priority and an NES state corresponding to the NSAG priority.

11. In paragraph 8, The above NES-related information includes Allowed NSSAI (network slice selection assistance information), A method characterized in that a PDU session establishment is requested for the above allowed NSSAI.

12. In a first network entity corresponding to AMF (access and mobility management function) in a wireless communication system, Transmitter and receiver; and A control unit comprising: Receives UE (user equipment) subscription information from a second network entity corresponding to UDM (unified data management), Receives a request message for Network Energy Saving (NES) from the UE; determining NES activation for the UE based on at least one of the UE subscription information or the request message, and It is set to transmit NES related information to the above UE, The first network entity, wherein the request message includes information on whether energy saving is allowed for the UE.

13. In paragraph 12, The above UE subscription information includes information on whether energy saving is allowed for each UE and information on the time during which energy saving is allowed for each UE. One or more UEs to which NES activation is applied are determined based on the information on whether energy saving is allowed for each UE, and A first network entity characterized in that NES activation for said one or more UEs is applied in a time band identified based on information about said time.

14. In paragraph 1, the control unit: Determine the NSAG (network slice access stratum group) priority for the above UE, and A first network entity further characterized by being configured to transmit information about the determined NSAG priority to the UE.

15. In a wireless communication system, in the UE (user equipment), Transmitter and receiver; and A control unit comprising: Transmits a request message for network energy saving (NES) to the first network entity corresponding to the AMF (access and mobility management function), and is configured to receive NES related information from the first network entity; The above request message includes information on whether energy saving is allowed for the UE, and Whether or not to activate NES for the above UE is determined based on the request message.

Images