阅读说明：本技术 终端的网络接入方法以及用于移动性支持和数据传送的方法和装置 (Network access method of terminal and method and device for mobility support and data transmission ) 是由 金成勋 白令教 李淏娟 孙仲济 A.班尼特 于 2018-06-12 设计创作，主要内容包括：本公开涉及用于融合IoT技术的通信技术和用于支持4G系统之外的更高数据传输速率的5G通信系统、及其系统。本公开可以基于5G通信技术和IoT相关技术应用于智能服务(例如,智能住宅、智能建筑、智能城市、智能或联网汽车、医疗保健、数字教育、零售业务以及与安全和安保相关的服务)。本发明提供了一种用于将下行链路数据缓冲到仅移动端发起通信模式的终端的方法和装置。(The present disclosure relates to a communication technology for converged IoT technology and a 5G communication system for supporting a higher data transmission rate than a 4G system, and a system thereof. The present disclosure may be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart or networked automobiles, healthcare, digital education, retail business, and security related services) based on 5G communication technology and IoT related technology. The present invention provides a method and apparatus for buffering downlink data to a terminal in a mobile-only originating communication mode.)

1. A communication method performed by a Session Management Function (SMF), the method comprising:

receiving information indicating an occurrence of downlink data from a User Plane Function (UPF);

determining whether a terminal corresponding to downlink data is an unreachable terminal or a mobile-only originating communication (MICO) mode terminal;

determining a buffering time for buffering the downlink data in case that the terminal is an unreachable terminal or the terminal is a MICO mode terminal; and

transmitting information about the buffering time to at least one of an access and mobility management function (AMF) and a UPF.

2. The method of claim 1, wherein determining whether the terminal is an unreachable terminal or the terminal is a MICO-mode terminal comprises:

transmitting information on the occurrence of downlink data to the AMF,

receiving at least one of information indicating that the terminal is an unreachable terminal and information indicating that the terminal is a MICO mode terminal from the AMF, and

determining whether the terminal is an unreachable terminal or the terminal is a MICO mode terminal based on information received from the AMF.

3. The method of claim 1, further comprising:

in case the SMF receives information indicating that the terminal is reachable according to the service request of the terminal from the AMF before the expiration of the buffer time, a connection activation procedure with the UPF and the terminal is performed.

4. The method of claim 1, further comprising:

receiving information indicating that the terminal is reachable according to a service request of the terminal from the AMF,

determining whether the buffer time has expired, an

Performing a connection activation procedure with the UPF and the terminal if the buffering time has not expired.

5. The method of claim 3, wherein performing the connection activation procedure with the UPF and the terminal comprises:

transmitting, to the AMF, a message for session establishment including information indicating that the downlink data is suspended.

6. A method of communication performed by an AMF, the method comprising:

receiving information indicating an occurrence of downlink data from the SMF;

determining whether a terminal corresponding to the downlink data is an unreachable terminal or the terminal is a terminal of a MIMO mode;

transmitting at least one of information indicating that the terminal is an unreachable terminal and information indicating that the terminal is a terminal of a MIMO mode to the SMF; and

receiving information on a buffering time for buffering the downlink data from the SMF.

7. The method of claim 6, further comprising:

receiving a service request message from the terminal;

determining whether the buffer time has expired; and

transmitting information to the SMF indicating that the terminal is reachable if the buffer time has not expired.

8. The method of claim 7, further comprising:

receiving a message for session establishment from the SMF including information indicating that the downlink data is suspended.

9. An SMF in a communication system, the SMF comprising:

a transceiver; and

a controller coupled with the transceiver and configured to:

receiving information indicating the presence of downlink data from the UPF,

determining whether a terminal corresponding to the downlink data is an unreachable terminal or the terminal is a MICO mode terminal,

determining a buffering time for buffering the downlink data in case the terminal is an unreachable terminal or the terminal is a MICO mode terminal, and

transmitting information about the buffering time to at least one of the AMF and the UPF.

10. The SMF of claim 9, wherein the controller transmits information indicating the presence of the downlink data to the AMF, receives at least one of information indicating that the terminal is an unreachable terminal and information indicating that the terminal is a MICO-mode terminal from the AMF, and determines whether the terminal is an unreachable terminal or the terminal is a MICO-mode terminal based on the information received from the AMF.

11. The SMF of claim 9, wherein the controller performs the connection activation procedure with the UPF and the terminal in case the SMF receives information indicating that the terminal is reachable according to the service request of the terminal from the AMF before the expiration of the buffer time.

12. The SMF of claim 9, wherein the controller receives information indicating that the terminal is reachable according to the service request of the terminal from the AMF, determines whether the buffering time expires, and performs a connection activation procedure with the UPF and the terminal if the buffering time does not expire.

13. The SMF of claim 11, wherein the controller transmits a message to the AMF for session establishment including information indicating that the downlink data is suspended.

14. An AMF, comprising:

a transceiver; and

a controller coupled with the transceiver and configured to:

receiving information from the SMF indicating an occurrence of downlink data,

determining whether a terminal corresponding to the downlink data is an unreachable terminal or the terminal is a MICO mode terminal,

transmitting at least one of information indicating that a terminal is an unreachable terminal and information indicating that the terminal is a MICO-mode terminal to the SMF, and

receiving information on a buffering time for buffering the downlink data from the SMF.

15. The AMF of claim 14, wherein the controller receives a service request message from the terminal, determines whether the buffer time expires, transmits information indicating that the terminal is reachable to the SMF in case the buffer time does not expire, and receives a message for session setup from the SMF, which includes information indicating that the downlink is suspended.

Technical Field

The present disclosure provides a method and apparatus for buffering downlink data to a terminal of a mobile-end-only communication mode.

Background

In order to meet the increasing radio data traffic demand since the commercialization of fourth generation (4G) communication systems, efforts have been made to develop improved fifth generation (5G) communication systems or pre-5G communication systems. Therefore, the 5G communication system or the pre-5G communication system is called a super 4G network communication system or a Long Term Evolution (LTE) system. In order to achieve high data transmission rates, 5G communication systems are considered to be implemented in the ultra-high frequency (millimeter wave) band (e.g., like the 60GHz band). In order to mitigate path loss of radio waves and increase transmission distance of radio waves in an ultra high frequency band, in a 5G communication system, beam forming, massive-Input Multiple-Output (MIMO), Full-Dimensional MIMO (FDMIMO), array antenna, analog beam forming, and massive antenna technologies have been discussed. Further, in order to improve the network of the system, in the 5G communication system, technologies such as evolved small cell (evolved small cell), advanced small cell (advanced small cell), cloud radio access network (cloud RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, mobile network, cooperative communication, coordinated multi-point (CoMP), reception interference cancellation have been developed. In addition, in the 5G system, a hybrid Frequency Shift Keying (FSK) and Quadrature Amplitude Modulation (QAM) (FSK and QAM Amplitude Modulation, FQAM) and Sliding Window Superposition Coding (SWSC) as Advanced Coding Modulation (ACM) schemes, and a filter bank Multi-Carrier (FBMC), a Non-Orthogonal Multiple Access (NOMA), a Sparse Code Multiple Access (SCMA), and the like as Advanced Access technologies have been developed.

Meanwhile, the Internet is evolving from a man-centric communication network, in which information is generated and consumed by humans, to an Internet of Things (IoT) network, in which distributed components, such as Things, exchange and process information. Internet of Everything (IoE) technology is also emerging, in which IoT technology is combined with big data processing technology connected to a cloud server or the like. Technical elements such as sensing (sensing) technology, wired/wireless Communication and network infrastructure, service interface technology, and security technology are required in order to implement IoT, and thus, recent research has been conducted on technologies for connection between things such as sensor networks, Machine-to-Machine (M2M), and Machine Type Communication (MTC). In the IoT environment, IT is possible to provide intelligent Internet Technology (IT) that is capable of collecting and analyzing data generated from Internet things, thereby creating new value for human life. Through the combination and fusion of existing Information Technology (IT) and various industries, IoT may be applied to various fields such as smart homes, smart buildings, smart cities, smart cars or networked cars, smart grids, healthcare, smart appliances, and advanced medical services.

Therefore, there are many attempts to apply the 5G communication system to the IoT network. For example, sensor networks, M2M, and MTC technologies are implemented with 5G communication technologies (such as beamforming, MIMO, and array antennas). The application of the cloud RAN described above as a big data processing technology is one example of the convergence between 5G technology and IoT technology.

Disclosure of Invention

Technical problem

The MICO represents that only the mobile terminal initiates communication, and the MICO mode terminal refers to a terminal that is connected to a network only when the terminal itself has data to transmit. In other words, when the MICO mode terminal is in the IDLE state, the MICO mode terminal does not perform an operation of receiving a page. Therefore, the network cannot wake up the MICO mode terminal in the IDLE state, and the network can determine that the corresponding terminal is reachable only when the MICO mode terminal wakes up and requests connection to the network.

The present disclosure provides a method for buffering downlink data for a terminal in a MICO mode in an SMF or a UPF and allocating a buffering timer to transmit the downlink data to the terminal in the MICO mode so that the buffered data can be transmitted to the terminal when the terminal becomes reachable. Further, the present disclosure provides a method for managing a buffer timer allocated by a plurality of SMFs in an AMF when a MICO mode terminal has a plurality of SMFs and PDU sessions.

Further, the present disclosure defines a network slice (network slice) composed of network resources capable of satisfying the requirements of each service in the 5G mobile communication. The mobile operator may define a network slice that is specific to each operator. The user sends the slice information to be used for 5G network access while having the slice information included in the registration message. Accordingly, the present disclosure provides a method for maintaining slice information security.

Regarding a method of efficiently managing a PDU session for non-third generation partnership project (3gpp) long term evolution, which is previously generated when NW-triggered deregistration for non-3 gpp access occurs in the case where a terminal is connected to a 5G network through 3gpp access and non-3 gpp access, a management method for processing the PDU session is required to solve a problem, such as a problem that a PDU session is unnecessarily deleted in the case where all PDU sessions for non-3 gpp access are deleted according to deregistration in the 5G network even though the terminal may continue to receive PDU sessions through 3gpp access; the problem of using unnecessary resources in a 5G network if PDU sessions are not deleted even though deregistration may occur for non-3 gpp access; and so on.

Furthermore, this may apply to the method of managing a PDU session for 3gpp, which PDU was previously generated when NW-triggered deregistration for 3gpp access occurs in case the terminal is connected to a 5G network through 3gpp access and non-3 gpp access. Thus, in the present disclosure, only the case where NW-triggered deregistration for non-3 gpp access occurs will be addressed.

Technical scheme

According to one aspect of the disclosure, a communication method performed by a Session Management Function (SMF) includes: receiving information indicating an occurrence of downlink data from a User Plane Function (UPF); determining whether a terminal corresponding to downlink data is an unreachable terminal or a mobile originated communication (MICO) only mode terminal; determining a buffering time for buffering downlink data in case that the terminal is an unreachable terminal or the terminal is a MICO mode terminal; and transmitting information on the buffering time to at least one of an access and mobility management function (AMF) and a UPF.

Further, the determining whether the terminal is an unreachable terminal or the terminal is a MICO-mode terminal includes: transmitting information on the occurrence of downlink data to the AMF, receiving at least one of information indicating that the terminal is an unreachable terminal and information indicating that the terminal is a MICO-mode terminal from the AMF, and determining whether the terminal is an unreachable terminal or the terminal is a MICO-mode terminal based on the information received from the AMF.

Further, the communication method of the SMF may further include performing a connection activation procedure with the UPF and the terminal in a case where the SMF receives information indicating that the terminal is reachable according to the service request of the terminal from the AMF before the expiration of the buffer time.

Further, the communication method of the SMF may further include receiving information indicating that the terminal is reachable according to a service request of the terminal from the AMF, determining whether the buffer time expires, and performing a connection activation procedure with the UPF and the terminal if the buffer time does not expire.

Further, performing the connection activation procedure with the UPF and the terminal may include transmitting a message for session establishment to the AMF, the message including information indicating that downlink data is suspended.

According to another aspect of the present disclosure, a communication method of an AMF includes: receiving information indicating the presence of downlink data from the SMF; determining whether a terminal corresponding to downlink data is an unreachable terminal or a terminal of a MIMO mode; transmitting at least one of information indicating that the terminal is an unreachable terminal and information indicating that the terminal is a terminal of a MIMO mode to the SMF; and receiving information on a buffering time for buffering the downlink data from the SMF.

In addition, the communication method of the AMF may further include receiving a service request message from the terminal; determining whether a buffer time has expired; and transmitting information indicating that the terminal is reachable to the SMF, in case the buffering time has not expired.

Further, the communication method of the AMF may further include receiving a message for session establishment from the SMF, the message including information indicating that downlink data is suspended.

According to another aspect of the present disclosure, a communication method of an SMF includes: a transceiver; and a controller configured to be connected to the transceiver, receive information indicating the presence of downlink data from the UPF, determine whether a terminal corresponding to the downlink data is an unreachable terminal or the terminal is a MICO-mode terminal, determine a buffering time for buffering the downlink data in case that the terminal is the unreachable terminal or the terminal is the MICO-mode terminal, and transmit information on the buffering time to at least one of the AMF and the UPF.

According to another aspect of the present disclosure, an AMF includes: a transceiver; and a controller configured to be connected to the transceiver, receive information indicating presence of downlink data from the SMF, determine whether a terminal corresponding to the downlink data is an unreachable terminal or the terminal is a MICO-mode terminal, transmit at least one of the information indicating that the terminal is the unreachable terminal and the information indicating that the terminal is the MICO-mode terminal to the SMF, and receive information on a buffering time for buffering the downlink data from the SMF.

Advantageous effects

The mobile communication service provider according to the embodiment may support delayed traffic transmission for each service used by the terminal or according to a request of an application server providing the service to the terminal. The MICO mode terminal is suitable for a terminal requiring low power communication, and thus, the MICO mode terminal is connected to a network to perform communication only when there is data to be transmitted by the terminal itself. However, when the traffic of the corresponding terminal is transmitted according to the request of the service or application server, the traffic may be transmitted while a specific delay time is desired. For example, the terminal may transmit "low priority" data that the terminal may respond to after 10 minutes or 1 hour without having to respond immediately. This is commonly referred to as high latency data communication. Delayed traffic transmission may occur due to congestion of user plane functions, regardless of specific service characteristics or AS requests. For example, if the user plane function is congested, there may be a time delay when transmitting response data to data transmitted by the terminal. If the terminal returns to IDLE mode during this delay, the corresponding network cannot wake up the MICO mode terminal and transmit the response data. Therefore, as an effect according to the embodiment, the network buffers downlink traffic for a terminal in the MICO mode for a service or traffic expected to be delayed for a certain time, and maintains the wireless connection of the terminal for a slightly longer time when the terminal is reachable, and thus can provide a data communication service without losing traffic transmitted to the terminal.

Further, according to the embodiment, security of slice information used by the terminal can be maintained.

Furthermore, by embodiments, the terminal may propose an NW-triggered deregistration scheme for non-3 gpp accesses and efficiently manage PDU sessions for non-3 gpp accesses, thereby efficiently managing resources in the 5G network.

Drawings

Fig. 1A and 1B are diagrams illustrating a procedure in which an SMF buffers downlink data for a terminal in a MICO mode and transmits a timer for the data to an AMF, which manages the timer and transmits a suspension data indication to a RAN node when the terminal wakes up.

Fig. 2 is a schematic diagram illustrating a process in which the SMF buffers downlink data for a MICO mode terminal, receives a notification from the AMF that the terminal becomes reachable, and then notifies the AMF of the presence of the buffered data, so that the AMF transmits a suspended data indication to the RAN node.

Fig. 3 is a schematic diagram illustrating a registration process according to an embodiment.

Fig. 4 is a schematic diagram illustrating a two-operation registration procedure including a temporary ID according to an embodiment.

Fig. 5 is a diagram illustrating a two-operation registration procedure that does not include a temporary ID according to an embodiment.

Fig. 6 is a schematic diagram illustrating a single operation registration process according to an embodiment.

Fig. 7 is a schematic diagram illustrating a two-operation registration procedure including a temporary ID for first transmitting an allowed NSSAI according to an embodiment.

Fig. 8 is a schematic diagram illustrating a two-operation registration procedure without a temporary ID for first transmitting an allowed NSSAI according to an embodiment.

Fig. 9 is a schematic diagram illustrating a single-operation registration procedure for first transmitting an allowed NSSAI, according to an embodiment.

Fig. 10 shows an example of a structure in which a terminal is connected to a 5G network through 3gpp access and non-3 gpp access according to an embodiment.

Fig. 11 illustrates a procedure in which a terminal connected to a 5G network through 3gpp access and non-3 gpp access according to an embodiment locally releases a PDU session for the non-3 gpp access or locally de-registers the non-3 gpp when the terminal cannot use the non-3 gpp access.

Fig. 12 shows a procedure in which a terminal connected to a 5G network through 3gpp access and non-3 gpp access according to an embodiment releases a PDU session for the non-3 gpp access locally or deregisters the non-3 gpp through the 3gpp access when the terminal cannot use the non-3 gpp access.

Fig. 13 shows a procedure in which a terminal connected to a 5G network through 3gpp access and non-3 gpp access cannot use the non-3 gpp access, the terminal transfers a PDU session of the non-3 gpp access to the 3gpp access through the 3gpp access, according to an embodiment.

Fig. 14 illustrates a procedure in which a terminal connected to a 5G network through 3gpp access and non-3 gpp access according to an embodiment releases a PDU session for non-3 gpp access or deregisters non-3 gpp through 3gpp access when the AMF recognizes that the terminal cannot use the non-3 gpp access through the N3 IWF.

Fig. 15 is a schematic diagram showing a configuration of a terminal according to an embodiment.

Fig. 16 is a schematic diagram showing a configuration of an SMF according to an embodiment.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description of the present disclosure, a detailed description of known functions or configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear. Terms to be described below are terms defined in consideration of functions in the present disclosure, and may be different according to a user, a user intention, or a habit. Therefore, the definition of the terms should be based on the contents of the entire specification.

Advantages and features of the present disclosure and the manner of attaining them will become apparent by reference to the following detailed description of embodiments when taken in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments set forth below, but may be implemented in various different forms. The following examples are provided solely for the purpose of complete disclosure and to inform those skilled in the art of the scope of the disclosure, and the disclosure is to be limited only by the scope of the appended claims. Throughout the specification, the same or similar reference numerals denote the same or similar elements.

It will be understood herein that each block of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart block or blocks. These computer program instructions may also be stored in a computer usable or computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer usable or computer-readable memory produce an article of manufacture including instruction means that implement the function specified in the flowchart block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks.

Also, each block of the flowchart illustrations may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of the order. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.

As used herein, a "unit" refers to a software element or a hardware element that performs a predetermined function, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). However, the "unit" does not always have a meaning limited to software or hardware. A "unit" may be configured to be stored in an addressable storage medium or to execute one or more processors. Thus, a "unit" includes, for example, software elements, object-oriented software elements, class elements or task elements, procedures, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and parameters. The elements and functions provided by a "unit" may be combined into a smaller number of element "units" or divided into a larger number of element "units". Further, the elements and "units" may be implemented to render one or more GPUs within a device or secure multimedia card.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description of the present disclosure, a detailed description of known functions or configurations incorporated herein will be omitted when it may make the subject matter of the present disclosure rather unclear. Terms to be described below are terms defined in consideration of functions in the present disclosure, and may be different according to a user, a user intention, or a habit. Therefore, the definition of the terms should be based on the contents of the entire specification.

Furthermore, the detailed description of the embodiments of the present disclosure is mainly based on OFDM-based wireless communication systems, in particular the 3gpp EUTRA standard, but the subject matter of the present disclosure may be applied to other communication systems having similar technical background and channel form after slight modifications without departing from the scope of the present disclosure, and the above may be determined by those skilled in the art.

Hereinafter, the operational principle of the present disclosure will be described in detail with reference to the accompanying drawings. In describing the present disclosure below, a detailed description of related known configurations or functions incorporated herein will be omitted when it is determined that the detailed description thereof may unnecessarily obscure the subject matter of the present disclosure. Terms to be described below are terms defined in consideration of functions in the present disclosure, and may be different according to a user, a user intention, or a habit. Therefore, the definition of the terms should be based on the contents of the entire specification. For convenience of explanation, terms for identifying an access node, terms related to network entities, terms related to messages, terms related to interfaces between network entities, terms related to various kinds of identification information, and the like, which are used in the following description, are exemplified. Accordingly, the present disclosure may not be limited by the terms provided below, and other terms indicating the subject matter having an equivalent technical meaning may be used.