Patent Description:
In order to meet wireless data traffic demands that have increased after 4th Generation (<NUM>) communication system commercialization, efforts to develop an improved <NUM> communication system or a pre-<NUM> communication system have been made. For this reason, the <NUM> communication system or the pre-<NUM> communication system is called a beyond-<NUM>-network communication system or a post-LTE system.

In order to achieve a high data transmission rate, an implementation of the <NUM> communication system in a mmWave band (for example, <NUM> band) is being considered. In the <NUM> communication system, technologies such as beamforming, massive MIMO, Full Dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, and large-scale antenna technologies are being discussed as means to mitigate a propagation path loss in the ultrahigh-frequency band and increase a propagation transmission distance.

Further, technologies such as evolved small cell, advanced small cell, cloud Radio Access Network (RAN), ultra-dense network, Device-to-Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and received interference cancellation have been developed in order to improve the system network in the <NUM> communication system.

In addition, the <NUM> system has developed Advanced Coding Modulation (ACM) schemes such as Hybrid FSK and QAM Modulation (FQAM) and Sliding Window Superposition Coding (SWSC), and has further developed advanced access technologies such as Filter Bank Multi Carrier (FBMC), Non Orthogonal Multiple Access (NOMA), and Sparse Code Multiple Access (SCMA).

Meanwhile, the Internet has been evolved to an Internet of Things (IoT) network in which distributed components such as objects exchange and process information from a human-oriented connection network in which humans generate and consume information. An Internet of Everything (IoE) technology in which a big data processing technology through a connection with a cloud server or the like is combined with the loT technology has emerged. In order to implement loT, technical factors such as a sensing technique, wired/wireless communication, network infrastructure, service-interface technology, and security technology are required, and research on technologies such as a sensor network, Machine-to-Machine (M2M) communication, Machine-Type Communication (MTC), and the like for connection between objects has recently been conducted. In an loT environment, through collection and analysis of data generated in connected objects, an intelligent Internet Technology (IT) service to create a new value for peoples' lives may be provided. The loT may be applied to fields, such as a smart home, smart building, smart city, smart car, connected car, smart grid, health care, smart home appliance, or high-tech medical service, through the convergence of the conventional Information Technology (IT) and various industries.

Accordingly, various attempts to apply the <NUM> communication to the loT network are made. For example, technologies such as a sensor network, Machine to Machine (M2M), and Machine Type Communication (MTC) are implemented by beamforming, MIMO, and array antenna schemes. The application of a cloud RAN as the big data processing technology may be an example of convergence of the <NUM> technology and the loT technology.

Document "<NPL>" discloses a solution on optimizing connection management based on NWDAF output.

Document "<NPL>" discloses 3GPP access specific aspects.

Document "<NPL>" discloses enhancing MICO for mobile terminated data/signalling.

Document "<NPL>" discloses network data analytics feedback.

Various embodiments suggest a device and a method, in which parameters that are used for managing an MICO mode are optimized and applied in consideration of the current network and service situation according to a situation of a terminal and the kinds of usable services in a <NUM> mobile network system.

The technical subjects pursued in the disclosure may not be limited to the above mentioned technical subjects, and other technical subjects which are not mentioned may be clearly understood, through the following descriptions, by those skilled in the art of the disclosure.

A method in a <NUM> mobile network system according to some embodiments includes: an operation of collecting a network and service information from network functions (NFs), external servers (an AF and a service server), a terminal, a <NUM> network management system (operation, administration, and management (OAM)) by a NEDAF; an operation of determining whether an MICO mode is used by a request of a terminal by an AMF; an operation of requesting network analysis information from the NWDAF to calculate MICO mode related parameters by the AMF; an operation of calculating the MICO mode related parameters by the AMF; an operation of activating a terminal MICO mode by applying the MICD mode related parameters by the AMF; and an operation of supporting a terminal that entered the MICO mode by a network.

Various embodiments include a device and a method for optimizing MICO mode related parameter values for reducing power consumption of a terminal in a mobile communication system.

Various embodiments include a procedure and a method for searching for an optimum value for MICO mode related parameters by using a technique such as artificial intelligence or mechanical learning on the basis of various objects provided by NWDAF, by an AMF.

In accordance with an aspect of the present disclosure, a method of a first network entity for an access and mobility management function (AMF) is provided. The method comprises receiving, from a terminal, a first message for requesting a registration of the terminal, the first message comprises information for indicating preference for mobile initiated communication only (MICO) mode of the terminal; transmitting, to a second network entity for a network data analytics function (NWDAF), a second message for requesting analytics information on the terminal; receiving, from the second network entity, a third message including analytics information on the terminal; and determining whether the MICO mode is allowed for the terminal based on the analytics information on the terminal.

In one embodiment, the analytics information comprises at least one of terminal communication analytics, terminal mobility analytics, and expected UE behavioral parameters.

In one embodiment, the method further comprises transmitting, to the terminal, a fourth message as a response to the first message including information indicating whether the MICO mode is allowed for the terminal.

In one embodiment, the method further comprises determining MICO mode parameters based on the analytics information on the terminal.

In one embodiment, the MICO mode parameters include at least one of information on an extended connected time for indicating a base station to keep the terminal in radio resource connection (RRC) connected state, information on an active time for indicating the terminal to enter the MICO mode when the active time expires, or information on a periodic registration timer for the terminal to perform a periodic registration.

In one embodiment, the second message further includes information on the terminal or a group of terminal.

The present disclosure also provides a method of a first network entity for a network data analytics function (NWDAF). The method comprises receiving, from a second network entity for an access and mobility management function (AMF), a first message for requesting analytics information on a terminal; and transmitting, to the second network entity, a second message including analytics information on the terminal.

In one embodiment, the first message further includes information on the terminal or a group of terminal.

In one embodiment, the method further comprises transmitting, to a third network entity, a third message for requesting to subscribe to an event for the terminal for notification of the event occurs; receiving, from the third network entity, a fourth message including information associated with the event; determining the analytics information on the terminal based on the fourth message; and transmitting, to the second network entity, the second message including the analytics information on the terminal.

The present disclosure also provides a first network entity for an access and mobility management function (AMF). The first network entity comprises a transceiver; and a controller configured to receive, from a terminal, a first message for requesting a registration of the terminal, the first message comprises information for indicating preference for mobile initiated communication only (MICO) mode of the terminal, transmit, to a second network entity for a network data analytics function (NWDAF), a second message for requesting analytics information on the terminal, receive, from the second network entity, a third message including analytics information on the terminal, and determine whether the MICO mode is allowed for the terminal based on the analytics information on the terminal.

The present disclosure also provides a first network entity for a network data analytics function (NWDAF). The first network entity comprises a transceiver; and a controller configured to receive, from a second network entity for an access and mobility management function (AMF), a first message for requesting analytics information on a terminal; and transmit, to the second network entity, a second message including analytics information on the terminal.

A device and a method according to various embodiments can minimize loss of data and degradation of service quality, which may be generated in reception of a service, by adjusting a service cut-off period, which may be generated when a terminal that employs a <NUM> mobile network system uses an MICO mode to reduce consumption of electric power, in consideration of the provided service and the characteristics of the terminal.

According to an embodiment, degradation of service quality due to entrance to an MICO mode can be prevented, and power consumption of a terminal can be remarkably reduced.

Effects obtainable from the disclosure may not be limited to the above mentioned effects, and other effects which are not mentioned may be clearly understood, through the following descriptions, by those skilled in the art of the disclosure.

In the following, the invention is best understood in view of <FIG>, <FIG> and <FIG>. The remaining embodiments, aspects and examples disclosed below are included for illustrative purposes and for facilitating the understanding of the invention.

In describing the embodiments, descriptions of technologies which are already known to those skilled in the art and are not directly related to the disclosure may be omitted.

Further, the size of each element does not entirely reflect the actual size.

However, the disclosure is not limited to the embodiments disclosed below, but may be implemented in various forms. The embodiments are provided to make the disclosure of the disclosure complete and fully inform those skilled in the art to which the disclosure pertains of the scope of the disclosure.

And each block of the flowchart illustrations may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing the specified logical function(s).

As used herein, the "unit" refers to a software element or a hardware element, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), which performs a predetermined function. However, the "unit does not always have a meaning limited to software or hardware. The "unit" may be constructed either to be stored in an addressable storage medium or to execute one or more processors. Therefore, the "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, processes, functions, properties, procedures, sub-routines, segments of a program code, drivers, firmware, micro-codes, circuits, data, database, data structures, tables, arrays, and parameters. The elements and functions provided by the "unit" may be either combined into a smaller number of elements, "unit" or divided into a larger number of elements, "unit". Moreover, the elements and "units" may be implemented to reproduce one or more CPUs within a device or a security multimedia card. Also, in an embodiment, the '~ unit' may include one or more processors.

While main targets are a wireless connection network new RAN (NR) on the <NUM> mobile communication standards, which are suggested by 3GPP that is a mobile communication standardization group, and a pack core (a <NUM> system, a <NUM> core network, or a next generation (NG) core) that is a core network in a detailed description of the embodiments, the main essences of the disclosure may be applied to other communication systems having a similar technical background in various modifications without greatly departing from the scope of the disclosure, and can be made possible by the determination of an ordinary person in the art to which the disclosure pertains.

Hereinafter, terms and names defined by the 3rd generation partnership project (3GPP) long term evolution standards (<NUM>, NR, LTE, or standards of the similar systems) may be partially used for convenience of description. However, the disclosure may not be limited by the terms and names, and may be equally applied to a system that is based on another standard.

The terms for identifying connection nodes, the terms that refer to network entities, the terms that refer to messages, the terms that refer to interfaces between the network entities, the terms that refer to various identification information, and the like, which are used in the following description, are exemplified for convenience of description.

The disclosure relates to a method for optimizing related parameters by utilizing an NWDAF when an access and mobility function (AMF), which manages an access and a mobility of the <NUM> mobile communication network of a terminal in a <NUM> mobile communication system, activates an MICO mode that allows the terminal only to initiate communication first by a request of the terminal.

The <NUM> mobile communication system defined a network data collection and analysis function (NWDAF) that provides a function of analyzing data collected by the <NUM> network and providing the collected data to support network automation. The NWDAF may collect, store, and analyze information from the <NUM> network to provide the result to an unspecific network function (NF), and the analysis result may be independently used by the NFs. The NWDAF may collect and analyze network information while taking network slices as basic units. However, the scope of the disclosure is not limited to the network slice units, and the NWDAF may additionally use various information, such as a user equipment (UE), a PDU session, and an NF state. The result analyzed by the NWDAF is delivered to the NFs that requested the result, and the delivered analysis result may be used to optimize network management functions, such as securement/enhancement of quality of service (QoS), traffic control, mobility management, and load dispersion.

The entities that appear in the disclosure may be described in the following.

<FIG> illustrates a network structure and an interface in a wireless communication system according to various embodiments.

The units that perform various functions provided by a <NUM> network system may be defined as a network function (NF). The structure of the <NUM> mobile communication network is illustrated in <FIG>. Representative NFs include an access and mobility management function (AMF)<NUM> that manages the network access and the mobility of a user equipment (UE) <NUM>, a session management function (SMF) <NUM> that performs a function related to a session, a user plane function (UPF) <NUM> that functions to deliver user data, an application function (AF) <NUM> that communicates with a 5GC for provision, a network exposure function (NEF) <NUM> that supports communication between the 5GC and the AF <NUM>, a unified data management (UDM) and unified data repository (UDR) <NUM> for storing and managing data, a policy and control function (PCF) <NUM> for managing a policy, and a data network (DN) <NUM>, such as an internet through which user data are delivered. In addition to the NFs, an operation, administration, and management (OAM) (not illustrated) that is a system for managing a terminal and a <NUM> mobile communication network may be present.

A network data analytics function (NWDAF) (not illustrated), which is an NF that aims to collect and analyze data, may be present. The NWDAF functions to analyze information collected from a network or the outside and provide the analysis result to the NF. The NWDAF may collect information from an NF or an AF that constitutes an OAM or a <NUM> network. The NWDAF may collect information in various methods. The representative analysis function of the NWDAF is to collect and analyze the load level of a network slice instance and provide the result to another NF to be used to select a specific UE <NUM> such that the specific UE <NUM> may be used. A service based interface defined by the <NUM> network is used in requesting analysis information or deliver the analysis result between a specific NF and the NWDAF.

In the <NUM> network, the NWDAF may provide the following services that provide a function of collecting and analyzing information. Of course, the disclosure is not limited to the following examples.

Nnwdaf_EventsSubscription Service: The event subscription service is for subscription and unsubscription of an event generated by the NWDAF, and the event subscription service may be classified into methods for receiving events periodically or when a specific condition is satisfied. The event subscription service is referred to as Nnwdaf_EventsSubscription. The Nnwdaf_EventsSubscription service provides three operations of subscription, unsubscription, and notification.

When a specific NF wants a subscription (Nnwdaf_EventsSubscription_Subscribe), a parameter delivered by the specific NF through the NWDAF may be classified into a required input parameter and an optional input parameter. According to some embodiments, a required input may include S-NSSAI (single network slice selection assistance information), an event identifier, a notification target address, and event reporting information. Of course, the disclosure is not limited to the examples. According to some embodiments, the optional input may include information that is additionally used for analysis information process, and may representatively include event filter information. Of course, the disclosure is not limited to the examples.

As an essential input for Nnwdaf_EventsSubscription_Unsubscribe, the NF delivers subscription identifier information to the NWDAF, and the NWDAF delivers the full text that notifies, as an output, that the release of subscription has been identified to the NF that requested an operation.

The Nnwdaf_EventsSubscription_NotifY is to notify, when the NWDAF satisfies a periodic or specific condition, the result to an NF that is successfully subscribing a specific event, for the specific event. Essential input information of the notification operation may include an event identifier, a notification target address, an identifier of a network slice instance, and the load level information of a network slice instance, and essential output information may not be present. Of course, the disclosure is not limited to the above examples.

An Nnwdaf_Analytics_Info service: Unlike the above-described event subscription service, an analysis request service may mean a service in which, after the NF requests analysis of specific information, a result value is delivered immediately after the request is completed. An operation of supporting by the analysis information request service includes a request and a response. The NF that requests analysis information may send an analysis information request to the NWDAF.

Generally, the NF sends, as essential inputs of the analysis information request, load level information of a network slice instance, an analytic ID, and additional parameters that are used for an analysis to the NWDAF. The NWDAF sends the analysis result to the NF when receiving a request from the NF. Load information of the requested slice is sent in the response.

While the analysis information provided through the service provided by the NWDAF considers only load information of the instance of the network slice according to the current Rel-<NUM> definition of the 3GPP, the information provided by the NWDAF is not limited only to the load information in the disclosure.

The disclosure includes expansion/modification of the above-described interface of the NWDAF, and includes a method for analyzing a UE behavioral pattern provided by the AF and an external provisioned parameter as well as network slice information between the NWDAF and the AMF, and inferring information that is not present or calculating an error rate of existing information through the data collected by the NWDAF to provide the inferred information or the error rate to the AMF or another NF. Moreover, the NWDAF may include a method for providing set parameters used for the MICO mode as recommended values.

In the disclosure, the AMF includes an embodiment of calculating a periodic registration that is a parameter related to the MICO mode usable for reduction of the electric power of the terminal, a minimal reachability maintain time before initiation of the MICO mode, and the size and time of a buffer that is used for the MICO mode. The disclosure aims to prevent degradation of service quality and maintain the power consumption of the terminal low by minimizing the values of the parameters according to the user usage pattern of the terminal and the form of the service by utilizing the NWDAF.

Whether the terminal may use the MICO mode in the existing 3GPP is determined by the AMF according to the internal policy of the service provider that manages the <NUM> network. In order to allow the terminal that may utilize the MICO mode to activate the MICO mode, a MICO mode preference is transmitted together in the registration process, and the AMF that received the MICO mode preference sends a MICO indication in a registration accept message. The terminal that is informed that the MICO mode may be initiated may initiate the MICO mode in a CM_IDLE state. The terminal may deliver the MICO mode preference during an initial registration and a registration update process, and may deliver whether the MICO mode is possible to the terminal through a registration accept message sent by the AMF and a set configuration update procedure. Thereafter, the terminal that is notified of whether the MICO mode is possible by the AMF initiates the MICO mode, and then, may not listen to all signals generated from the network. The terminal should wake up at the next periodic registration time point and inform the AMF that the terminal is registered in the network through a registration update procedure. That is, the MICO mode initiation time point and the wakeup time point of the terminal are determined according to the registration update period. The disclosure includes finding an optimum value between data loss and degradation of service quality according to battery consumption of the terminal and data transmission by adjusting the registration period of the terminal.

In the MICO mode, a method capable of delivering data to the terminal until the terminal wakes up again is not present because the terminal does not listen to all signals generated in the <NUM> network after the terminal initiates the MICO mode due to the characteristics thereof. Accordingly, when data that are to be delivered from the outside to the terminal is scheduled in the near future, it is necessary to maintain the accessibility of the terminal. Here, the accessibility refers to a state in which the terminal may be provided with a network service through a call of the AMF, and both of CM_IDLE and CM_CONNECTED may correspond to the accessibility. Currently, the 3GPP has two methods for applying a minimum time period, for which the accessibility has to be maintained, before the terminal initiates the MICO mode. The first is a method for utilizing a connected time value that refers to a minimum time period only when the AMF maintains the RAM in an RRC_CONNECTED state. The second is a method for utilizing an active timer that means a standby time period from the initiation of a CM_IDLE mode to the initiation of the MICO mode when the UE (terminal) is registered in the network. Both of the two methods are methods for guaranteeing the accessibility of the terminal for a specific period of time before the terminal initiates the MICO mode. Accordingly, the terminal has to be made to initiate the MICO mode as quickly as possible such that there is no loss or delay of data by optimizing the period of time, for which the terminal waits before the initiation of the MICO mode.

Data cannot be delivered after the terminal initiates the MICO mode, and the basic operation then is to drop data packets. However, if the number and the size of the data packets that is to be received until the terminal wakes up the next time is known, data may be transferred without loss of data by buffering downstream data by an SMF or a UPF. It is necessary to determine whether downstream data packets come in a level at which buffering is possible, and analyze the time period for buffering and the size and the number of the data that are to be buffered.

The AMF may utilize external provisioned parameters that are received from the AF to derive the MICO mode related set parameters. As communication pattern parameters, the representative external parameters include a network configuration parameter, an expected UE trajectory, and an expected UE behavioral pattern. In the disclosure, the external parameters are not explicitly defined as a set of specific parameters, and refer to parameters that are received from an external AF.

In order to determine the MICO mode related parameters, the current AMF determines values by performing a calculation algorithm of its own through the data collected by itself and the external parameters received from the AF. While the determination method for the values may vary according to implementation of the AMF, the analysis data that may be collected by the AMF is limited according to the definition of the 3GPP standards and thus it is difficult to derive an optimum value.

The disclosure includes a method for optimization of the MICO mode related set value, collecting and analyzing various data and providing the analyzed data to the AMF by the network, the terminal, the AF, and the network management system. The NWDAF collects data from the above entities for collection of data. The data collected from the 5GC NFs are listed in Table <NUM>. The data collected by the terminal that is an external object, the AF, and the network management system is listed in Table <NUM>. The process of collecting data is illustrated in <FIG> illustrates a relationship with other objects for collecting data in an NWDAF according to an embodiment. Referring to <FIG>, the NWDAF <NUM> may receive subscription data and/or external parameters from a UDM/UDR <NUM> (operation <NUM>). The NWDAF <NUM> may receive service data from an AF <NUM> (through an NEF <NUM>) (operation <NUM>). The NWDAF <NUM> may receive session data from an SMF <NUM> (operation <NUM>). The NWDAF <NUM> may receive access/mobility data from an AMF <NUM> (operation <NUM>). The NWDAF <NUM> may receive UE analytics from a UE <NUM> (through a base station (NG-RAN) <NUM>) (operation <NUM>). The NWDAF <NUM> may receive policy data from a PCF <NUM> (operation <NUM>). The operations of <FIG> do not indicate the generation sequence, and the operations illustrated are not generated in the illustrated sequence. Analysis of the collected data and prediction or analysis of the parameters that are used in the embodiments may vary according to an algorithm and a purpose.

In the disclosure, when the AMF receives a registration request including an MICO mode preference from the terminal, the AMF calculates whether the MICO mode of the terminal is accommodated and a periodic registration timer value and sends the result together the registration update message. In addition, the terminal does not initiate the MICO mode immediately after CM_CONNECTED is changed to CM_IDLE but the AMF calculates a minimum time period, for which an accessibility has to be maintained for a specific time period, and delivers the result to the UE or the RAN. Then, the method for applying a communicable state to a maintenance time period follows the standard of the 3GPP. Next, when the SMF receives a signal indicating that downstream data came to the terminal in the MICO mode, the AMF informs the SMF that the terminal cannot be currently accessed and informs of a buffering time and the size of the buffer. Then, the NF that buffers may be the SMF or the UPF, and is operated according to the standards of the 3GPP.

<FIG> illustrates a procedure that supports an MICO mode by requesting an external parameter, which has not been delivered by an AMF from the NWDAF, according to an embodiment.

The present embodiment will be discussed with reference to <FIG>.

In operation <NUM>, the NWDAF <NUM> collects the above-described data from the NFs <NUM>, <NUM>, <NUM>, <NUM>, and the like, the UE <NUM>, the AF <NUM>, and the OAM (not illustrated) and analyzes the data. The collection of the data follows a procedure in the standards ruled by the 3GPP.

In operation <NUM>, the terminal <NUM> performs a registration procedure, and when the terminal <NUM> can activate the MICO mode, writes a MICO mode preference in a registration message according to the internal decision.

In operation <NUM>, the AMF <NUM> may collect subscription information, access information, mobility information management information, and information for registration of the terminal <NUM> from the PCF <NUM> and the UDM/UDR <NUM>. The AMF <NUM> may bring external parameters stored in the UDM/UDR <NUM>.

In operation <NUM>, in the case in which the MICO mode preference of the terminal <NUM> is requested when the registration procedure is performed, the AMF <NUM> detects an MICO mode indication, parameters that are used for determining related parameters, and parameters that are not currently carried. The AMF <NUM> may receive related external parameters and internal parameters in advance from the AF <NUM> and the UDR/UDM <NUM> though the procedure ruled by the 3GPP.

In operation <NUM>, the AMF <NUM> requests inferred/predicted values of the external parameters, which are not carried by the AMF <NUM>, from the NWDAF <NUM>. The AMF <NUM> sends an analysis request to the NWDAF <NUM> while an event ID and a target for the external parameter are taken as a parameter when requested. The AMF <NUM> may additionally limit the target to a specific terminal, a specific terminal group, a specific network slice, and a specific area and send the limited target.

In operation <NUM>, the NWDAF <NUM> may calculate an analysis/prediction value of the parameters requested by the AMF <NUM> and return the calculated value to the AMF <NUM>. The NWDAF <NUM> may transmit an accuracy or a reliability for the result values together.

In operation <NUM>, (optionally) the NWDAF <NUM> may renew the UDR/UDM <NUM> and allow the calculation result value to be used later if the calculated result is not present in the UDR/UDM <NUM>.

In operation <NUM>, (optionally) the NWDAF <NUM> may send a notification through the NEF <NUM> and deliver the information to the AF <NUM> if the calculated result is different from the value received from the AF <NUM>.

In operation <NUM>, the AMF <NUM> determines a MICO mode indication, a periodic registration timer, a minimal reachable time, and a buffer size and time, which are MICO mode related parameters, by using the received analyzed/predicted parameter values.

In operation <NUM>, the AMF <NUM> responds to the terminal <NUM> while a MICO mode indication and a periodic registration timer are included in the registration accept message. When the minimal reachable time is managed by the terminal <NUM> (e.g., an active timer is used), the minimal reachable time is delivered to the terminal <NUM> together. When the minimal reachable time is managed by the RAN <NUM> (e.g., when a connected timer value is used), the minimal reachable time may be delivered to the RAN <NUM> through an N2 interface.

In operation <NUM>, the terminal <NUM> uses a 5GC service. Thereafter, in operation <NUM>, the terminal <NUM> initiates the MICO mode after standing by for a minimal reachable time before initiating the MICO mode.

In operation <NUM>, downstream data from the outside <NUM> to the terminal <NUM> may be generated.

In operation <NUM>, the SMF <NUM> sends a call request to the AMF <NUM>.

In operation <NUM>, after identifying that the terminal <NUM> initiated the MICO mode, the AMF <NUM> determines the buffer size by predicting a time at which the terminal <NUM> wakes up the next time.

In operation <NUM>, the AMF <NUM> sends the determined buffer size in response to the SMF <NUM>. The location at which the packets are buffered follows the standards of the 3GPP.

In operation <NUM>, downstream packets of the terminal <NUM> in the MICO mode are buffered at a location at which the packets according to the 3GPP standards are buffered.

The disclosure is a method for, when external parameters are received in advance from the AF or the UDM/UDR, identifying the healthiness of the received parameters in the first embodiment. The AF may set an arbitrary value or a too large or small value due to lack of clear understanding of a communication pattern of a service. This is for preventing the MICO mode related parameter(s) from failing to be optimized due to the operation. The present embodiment may be used together with the first embodiment.

<FIG> illustrates a procedure that supports the MICO mode by requesting an error analysis of an external parameter, which has been delivered by the AMF from the NWDAF, according to an embodiment.

In operation <NUM>, the NWDAF <NUM> is collecting the above-described data from the NFs <NUM>, <NUM>, <NUM>, <NUM>, and the like, the UE <NUM>, the AF <NUM>, and the OAM (not illustrated) and is analyzing the data. The collection of the data follows a procedure in the standards ruled by the 3GPP.

In operation <NUM>, the AMF <NUM> requests analysis values from the NWDAF <NUM> to recognize errors of the external parameters, which are currently carried by the AMF <NUM>. The AMF <NUM> sends an analysis request while an event ID and a target for the external parameter are taken as a parameter when requested. The AMF <NUM> may additionally limit the target to a specific terminal, a specific terminal group, a specific network slice, and a specific area and send the limited target.

In operation <NUM>, (optionally) the NWDAF <NUM> may renew the UDR/UDM <NUM> and allow the calculation result value to be used later if the calculated result is not present in the UDR/UDM <NUM>. The UDR/UDM <NUM> may simultaneously store the value received from the AF <NUM> and the analyzed value, or may express an error value of the received value.

In operation <NUM>, (optionally) the NWDAF <NUM> may send a notification through the NEF <NUM> and deliver the information to the AF <NUM> if the calculated result is not received from the AF <NUM>.

In operation <NUM>, the AMF <NUM> determines a MICO mode indication, a periodic registration timer, a minimal reachable time, and a buffer size and time, which are MICO mode related parameters, by correcting the received analyzed/predicted parameter values.

The disclosure is a case in which the AMF receives an MICO mode indication, a periodic registration timer, a minimal reachable time, and a buffer size and time, which are MICO mode related parameters, from the NWDAF in the form of a recommended value. The AMF functions to trust the determination of the MICO mode related parameter(s) to the NWDAF or monitor an allowable range of the values.

<FIG> illustrates a procedure that supports the MICO mode by requesting a recommendation value for a MICO mode related parameter, which has not been delivered by the AMF from the NWDAF, according to an embodiment.

In operation <NUM>, the terminal <NUM> performs a registration procedure, and when the terminal <NUM> can activate the MICO mode, writes a MICO mode preference in a registration message.

In operation <NUM>, in the case in which an MICO mode preference of the terminal <NUM> is requested when a registration procedure is performed, the AMF <NUM> detects that it is necessary to determine an MICO mode indication and calculate related parameters.

In operation <NUM>, the AMF <NUM> requests a recommended value of the MICO mode related parameter(s) from the NWDAF <NUM>. The AMF <NUM> sends an analysis request while event IDs and targets for the MICO mode related parameter are taken as parameters when requested. The AMF <NUM> may additionally limit the target to a specific terminal, a specific terminal group, a specific network slice, and a specific area and send the limited target. Then, the MICO mode related parameter(s) is not limited to an MICO mode indication, a periodic registration timer, a minimal reachable time, and a buffer size and time.

In operation <NUM>, the AMF <NUM> reviews the received analyzed/predicted parameter values, and determines whether a MICO mode indication, a periodic registration timer, a minimal reachable time, and a buffer size and time, which are MICO mode related parameters, by using the received analyzed/predicted parameter values are to be applied.

A method in a <NUM> mobile network system according to the above-described embodiments includes:* an operation of collecting a network and service information from network functions (NFs), external servers (an AF and a service server), a terminal, a <NUM> network management system (operation, administration, and management (OAM)) by a NEDAF; an operation of determining whether an MICO mode is used by a request of a terminal by an AMF; an operation of requesting network analysis information from the NWDAF to calculate MICO mode related parameters by the AMF; an operation of calculating the MICO mode related parameters by the AMF; an operation of activating a terminal MICO mode by applying the MICD mode related parameters by the AMF; and an operation of supporting a terminal that entered the MICO mode by a network. According to various embodiments, a device and a method for optimizing MICO mode related parameter values for reducing power consumption of a terminal in a mobile communication system may be provided. Various embodiments may provide a procedure and a method for searching for an optimum value for MICO mode related parameters by using a technique such as artificial intelligence or mechanical learning on the basis of data collected from various objects provided by the NWDAF.

<FIG> illustrates a view of a configuration of a network entity according to an embodiment.

The network entity according to an embodiment may include a transceiver <NUM> and a controller that controls an overall operation of the network entity. The transceiver <NUM> may include a transmitter <NUM> and a receiver <NUM>.

The transceiver <NUM> may transmit and receive signals to and from other network entities.

The controller <NUM> may control the network entity to perform any one operation of the above-described embodiments. The controller <NUM> and the transceiver <NUM> are not necessarily realized as separate modules, and it is apparent that they may be realized by one configuration in a form such as a single chip. The controller <NUM> and the transceiver <NUM> may be electrically connected to each other. For example, the controller <NUM> may be a circuit, an application-specific circuit, or at least one processor. The operations of the network entity may be realized by providing a memory device storing the corresponding program codes in an arbitrary configuration in the network entity.

The network entity may be a terminal, AMF, NWDAF, RN-RAN, SMF, UPF, AF, NEF, UDM/UDR, PCF, and DN.

Claim 1:
A method performed by an access and mobility management function, AMF, the method comprising:
receiving (<NUM>, <NUM>), from a terminal, a first message for requesting a registration of the terminal, the first message comprising information for indicating preference for mobile initiated communication only, MICO, mode;
transmitting (<NUM>, <NUM>), to a network data analytics function, NWDAF, a second message for requesting analytics information on the terminal;
receiving (<NUM>, <NUM>), from the NWDAF, a third message including the analytics information on the terminal, as a response to the second message; and
determining (<NUM>, <NUM>) whether the MICO mode is allowed for the terminal based on the analytics information on the terminal,
wherein the analytics information comprises first analytics on a terminal communication pattern parameter, second analytics on an expected terminal behavioral parameter, and reliability for the first analytics and the second analytics.