Method and apparatus for managing session by using QUIC protocol in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate than that of a 4G communication system such as LTE. A method by which an SMF entity uses a QUIC connection for PDU session establishment in a wireless communication system according to the present disclosure may comprise the steps of: transmitting, to a UPF entity, an N4 session establishment request message; receiving an N4 session establishment response message from the UPF entity in response to the N4 session establishment request message; transmitting, to a base station through an AMF entity, first N2 information based on the N4 session establishment response message; receiving second N2 information from the base station through the AMF entity; and performing communication by using a QUIC connection. Various other embodiments identified through the specification are possible.

Description

Method and device for managing sessions using the QUIC protocol in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and device for managing a PDU session using the QUIC (quick UDP (user datagram protocol) internet connection) protocol in a wireless communication system.

[0002] Looking back at the development process through the successive generations of wireless communication, technologies have been developed primarily for human-targeted services such as voice, multimedia, and data. 5G (5 th Connected devices, which have been increasing explosively since the commercialization of 6G (6 Generation) communication systems, are expected to be connected to communication networks. Examples of networked objects include vehicles, robots, drones, home appliances, displays, smart sensors installed in various infrastructures, construction machinery, and factory equipment. Mobile devices are also expected to evolve into various form factors, such as augmented reality glasses, virtual reality headsets, and holographic devices. th In the era of 5G, efforts are being made to develop an improved 6G communication system to connect hundreds of billions of devices and objects and provide diverse services. For this reason, 6G communication systems are being referred to as "beyond 5G" systems.

[0003] The 6G communication system, expected to be realized around 2030, will have a maximum transmission speed of terabytes (i.e., 1,000 gigabits) per second (bps) and a wireless latency of 100 microseconds (μsec). In other words, compared to 5G, the transmission speed in a 6G communication system will be 50 times faster and the wireless latency will be reduced to one-tenth.

[0004] To achieve these high data rates and ultra-low latency, 6G communication systems are being considered for implementation in the terahertz (THz) band (e.g., from 95 gigahertz (GHz) to 3 terahertz (THz)). Compared to the millimeter wave (mmWave) band introduced in 5G, the terahertz band is expected to have more severe path loss and atmospheric absorption, making it more important to develop technologies that can guarantee signal reach, or coverage. Key technologies to ensure coverage include Radio Frequency (RF) components, antennas, new waveforms that offer better coverage than Orthogonal Frequency Division Multiplexing (OFDM), beamforming, and multiple antenna transmission technologies such as massive Multiple-Input and Multiple-Output (MIMO), Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas. In addition, new technologies such as metamaterial-based lenses and antennas, high-dimensional spatial multiplexing using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS) are being discussed to improve the coverage of terahertz band signals.

[0005] In addition, in order to improve frequency efficiency and system network, 6G communication systems are developing full duplex technology that utilizes the same frequency resources at the same time for uplink and downlink; network technology that integrates satellites and HAPS (High-Altitude Platform Stations); network structure innovation technology that supports mobile base stations and enables optimization and automation of network operation; dynamic spectrum sharing technology through collision avoidance based on spectrum usage prediction; AI-based communication technology that utilizes AI (Artificial Intelligence) from the design stage and internalizes end-to-end AI support functions to realize system optimization; and next-generation distributed computing technology that realizes services with complexity that exceeds the limits of terminal computing capabilities by utilizing ultra-high-performance communication and computing resources (Mobile Edge Computing (MEC), cloud, etc.). In addition, efforts are being made to further strengthen connectivity between devices, further optimize networks, promote softwareization of network entities, and increase the openness of wireless communications through the design of new protocols to be used in 6G communication systems, the implementation of hardware-based security environments, the development of mechanisms for the safe use of data, and the development of technologies for maintaining privacy.

[0006] Research and development of these 6G communication systems are expected to enable a new level of hyper-connected experience through the hyper-connectivity of 6G communication systems, which encompass not only connections between things but also connections between people and things. Specifically, 6G communication systems are expected to enable services such as truly immersive eXtended Reality (XR), high-fidelity mobile holograms, and digital replicas. Furthermore, services such as remote surgery, industrial automation, and emergency response, which are provided through 6G communication systems through enhanced security and reliability, will be applied in diverse fields such as industry, medicine, automobiles, and home appliances.

[0007] Meanwhile, applications utilized in 6G communication systems include extended reality (XR), virtual reality (VR), and the metaverse, which promise high data rates, low latency, and high reliability. These applications exhibit significantly different traffic characteristics compared to traditional voice and streaming traffic, requiring separate traffic management.

[0008] Furthermore, the network architecture of 6G communication systems is being considered as fully cloud-native systems, leveraging the abundant resources of this fully cloud-native architecture to ensure high throughput and low latency communication performance. However, these cloud environments are prone to blackouts and communication system failures due to traffic interruptions, errors, and defects. Therefore, a network that can guarantee uninterrupted connectivity, meeting user expectations, is essential.

[0009] Accordingly, there is currently discussion on a protocol that can be applied to the user plane in 6G communication systems to enable management of data traffic by type and provide high data rates so that applications can operate smoothly without interruption.

[0010] Various embodiments disclosed in this document provide a method and apparatus for managing a session using the QUIC protocol in a wireless communication system for transmitting and receiving data traffic at high data rates and low latency.

[0011] According to various embodiments disclosed in the present document, a method for a session management function (SMF) entity to use a quick user datagram protocol internet connection (QUIC) connection to establish a PDU session in a wireless communication system includes the steps of: transmitting an N4 session establishment request message to a user plane function (UPF) entity; receiving an N4 session establishment response message in response to the N4 session establishment request message from the UPF entity; transmitting first N2 information based on the N4 session establishment response message to a base station via an access and mobility management function (AMF) entity; receiving second N2 information from the base station via the AMF entity; and performing communication using the QUIC connection, wherein the first N2 information may include at least one of information on the number of streams to be included in the QUIC connection, a mapping rule of a stream identifier (ID) and a quality of service flow identifier (QFI), and a UPF connection ID.

[0012] According to various embodiments disclosed in the present document, a method performed by a user plane function (UPF) entity in a wireless communication system includes the steps of: receiving an N4 session establishment request message from a session management function (SMF) entity; transmitting an N4 session establishment response message to the SMF entity in response to the N4 session establishment request message, wherein the N4 session establishment request message is based on an SM policy updated by the SMF entity for a QUIC connection, and the N4 session establishment response message may include a UPF connection ID.

[0013] According to various embodiments disclosed in the present document, a session management function (SMF) entity using a quick user datagram protocol internet connection (QUIC) connection for establishing a PDU session in a wireless communication system includes a transceiver and a controller coupled with the transceiver, wherein the controller transmits an N4 session establishment request message to a user plane function (UPF) entity, receives an N4 session establishment response message in response to the N4 session establishment request message from the UPF entity, transmits first N2 information based on the N4 session establishment response message to a base station through an access and mobility management function (AMF) entity, and receives second N2 information from the base station through the AMF entity, and is configured to perform communication using the QUIC connection, wherein the first N2 information may include at least one of information on the number of streams to be included in the QUIC connection, a mapping rule of a stream identifier (ID) and a quality of service flow identifier (QFI), and a UPF connection ID. there is.

[0014] According to various embodiments disclosed in the present document, in a wireless communication system, a user plane function (UPF) entity includes a transceiver and a controller coupled with the transceiver, and the controller is configured to receive an N4 session establishment request message from a session management function (SMF) entity, and to transmit an N4 session establishment response message to the SMF entity in response to the N4 session establishment request message, wherein the N4 session establishment request message is based on an SM policy updated by the SMF entity for a QUIC connection, and the N4 session establishment response message may include a UPF connection ID.

[0015] FIG. 1 illustrates a protocol stack structure of a user plane including a QUIC (quick user datagram protocol (UDP) internet connection) protocol according to one embodiment of the present disclosure.

[0016] FIG. 2 illustrates the header and message format of the QUIC protocol according to one embodiment of the present disclosure.

[0017] FIG. 3 illustrates an example of performing communication using the QUIC protocol according to one embodiment of the present disclosure.

[0018] FIG. 4 illustrates a method of operating a PDU (packet data unit) session using the QUIC protocol according to one embodiment of the present disclosure.

[0019] FIG. 5 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0020] FIG. 6 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0021] FIG. 7 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0022] FIG. 8 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0023] FIG. 9 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0024] FIG. 10 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0025] FIG. 11 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0026] FIG. 12 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0027] FIG. 13 illustrates an operation of establishing a PDU session according to one embodiment of the present disclosure.

[0028] FIG. 14 illustrates an operation of releasing a PDU session according to one embodiment of the present disclosure.

[0029] FIG. 15 illustrates an operation of modifying a PDU session according to one embodiment of the present disclosure.

[0030] FIG. 16 illustrates an operation for establishing a PDU session of an SMF (session management function) entity according to one embodiment of the present disclosure.

[0031] FIG. 17 illustrates the structure of a base station according to one embodiment of the present disclosure.

[0032] FIG. 18 illustrates the structure of a terminal according to one embodiment of the present disclosure.

[0033] FIG. 19 illustrates the structure of a core network according to one embodiment of the present disclosure.

[0034] In connection with the description of the drawings, the same or similar reference numerals may be used for identical or similar components.

[0035] Various aspects of the claimed subject matter are described with reference to the drawings, wherein like reference numerals are used to designate similar elements. In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of one or more embodiments. However, it may be apparent that the embodiments may be practiced without these specific details.

[0036] The terms used in this disclosure are used only to describe specific embodiments and may not be intended to limit the scope of other embodiments. The singular expression may include the plural expression unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by those of ordinary skill in the art described in this disclosure. Terms defined in general dictionaries among the terms used in this disclosure may be interpreted as having the same or similar meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this disclosure. In some cases, even if a term is defined in this disclosure, it cannot be interpreted to exclude embodiments of the present disclosure.

[0037] In the following description, terms referring to signals (e.g., message, signal, signaling, sequence, stream), terms referring to resources (e.g., symbol, slot, subframe, radio frame, subcarrier, resource element (RE), resource block (RB), bandwidth part (BWP), occasion), terms for operations (e.g., step, method, process, procedure), terms referring to data (e.g., information, parameter, variable, value, bit, symbol, codeword), terms referring to channels, terms referring to control information (e.g., downlink control information (DCI), medium access control code word element (MAC CE), radio resource control (RRC) signaling), terms referring to network entities, terms referring to components of devices, etc. are used in the description. These terms are provided for convenience. Therefore, the present disclosure is not limited to the terms described below, and other terms with equivalent technical meanings may be used.

[0038] Various embodiments of the present disclosure are described herein with respect to a wireless terminal and / or a base station. A wireless terminal may refer to a device that provides voice and / or data connectivity to a user. A wireless terminal may be connected to a computing device, such as a laptop or desktop computer, or may be a self-contained device, such as a personal digital assistant (PDA). A wireless terminal may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile, a mobile device, a remote station, a remote terminal, an access terminal, a user terminal, a terminal, a wireless communication device, a user agent, a user device, or user equipment. A wireless terminal may be a subscriber station, a wireless device, a cellular telephone, a PCS telephone, a cordless telephone, a Session Initiation Protocol (SIP) telephone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless access capabilities, or another processing device connected to a wireless modem. A base station (e.g., an access point) may refer to a device within an access network that communicates with wireless terminals over a wireless interface through one or more sectors. The base station can incorporate an Internet Protocol (IP) network by converting received air interface frames into IP packets and can act as a router between the wireless terminals and the rest of the access network. The base station can also coordinate the management of attributes for the air interface.

[0039] FIG. 1 illustrates a protocol stack structure of a user plane including a QUIC (quick user datagram protocol (UDP) internet connection) protocol according to one embodiment of the present disclosure.

[0040] Current 5G communication systems use the GTP-U (GPRS (general packet radio service) tunneling protocol-U) protocol, which is based on the user datagram protocol (UDP) as the user plane protocol. The GTP-U protocol supports tunneling of user data through the N3 interface between the gNB and the UPF in the backbone network, and the N9 interface between the UPF and different UPFs. The GTP-U protocol has a fast transmission speed because it does not require a logical connection establishment process, but it requires address information to be set and transmitted every time a datagram is transmitted. Furthermore, the UDP-based GTP-U protocol does not perform data flow control, error control, or congestion control, which can cause data loss during data transmission and reception. In other words, while UDP in the GTP-U-based user plane protocol enables high-speed data transmission and reception, it may have the problem of difficulty in ensuring uninterrupted connectivity, which is important in a mobile environment.

[0041] In one embodiment, the QUIC protocol may be used instead of the GTP-U protocol to configure a PDU session. The user plane protocol stack including the GTP-U protocol cannot include new unique information of the new protocol. To operate a PDU session using the new protocol, the user plane protocol stack structure needs to be changed. Accordingly, the present disclosure proposes the QUIC protocol, a new protocol for the user plane that can reduce data transmission and reception and promote low-latency data transmission.

[0042] Referring to FIG. 1, the protocol stack structure of the user plane of the present disclosure may include the QUIC protocol in the protocol stack associated with the N3 interface and the N9 interface. For example, in the protocol stack of the user plane used in a communication system, the GTP-U protocol may be replaced with the QUIC protocol to configure a PDU session.

[0043] In one example, a user-plane protocol stack structure that converts the GTP-U protocol to the QUIC protocol can be utilized in the network of a 6G communication system. Unlike the GTP-U protocol, the QUIC protocol can manage PDU sessions as multiple streams. Therefore, even if one stream experiences delays or data loss in transmission or reception, normal data transmission and reception can occur in other streams. Accordingly, a network utilizing the QUIC protocol can be utilized in the operation of applications in 6G communication systems that require low latency and high data rates.

[0044] In this disclosure, communication can be performed using a PDU session using the QUIC protocol. A PDU session using the QUIC protocol can be referred to as a QUIC connection. For the purpose of explanation, the terms PDU session using the QUIC protocol and QUIC connection are used interchangeably below.

[0045] FIG. 2 illustrates the header and message format of the QUIC protocol according to one embodiment of the present disclosure.

[0046] In existing 5G communication systems, user plane PDU sessions are structured based on the GTP-U protocol. Since PDU sessions based on the GTP-U protocol operate by utilizing the TEID (tunnel endpoint identifier) ​​message field, the user plane protocol stack based on the GTP-U protocol cannot include new unique information of the new protocol (e.g., connection ID, stream ID, etc.). Accordingly, in order to operate PDU sessions using the QUIC protocol, not only the protocol stack structure of the user plane but also the header format and message format used by the QUIC protocol can be additionally defined.

[0047] Referring to FIG. 2, a header (210) of the QUIC protocol is illustrated. The header (210) of the QUIC protocol may include identifiers used by the QUIC protocol. Specifically, the header (210) of the QUIC protocol may include information related to a connection ID (e.g., a gNB connection ID or a UPF connection ID) used when transmitting and receiving messages. In one example, the connection ID may be unique information included in the QUIC protocol.

[0048] While the GTP-U protocol can send and receive messages using the TEID in its header, the QUIC protocol can send and receive messages using the connection ID. Accordingly, the QUIC protocol header in FIG. 2 can include information related to the connection ID instead of the TEID.

[0049] Specifically, Destination Connection ID Length includes information indicating the length of the Destination Connection ID, Destination Connection ID includes information about the Destination ID, Source Connection ID Length includes information indicating the length of the Source Connection ID, and Source Connection ID may include information about the Source ID. However, the present invention is not limited to the above examples.

[0050] Additionally, the QUIC protocol header may include a Header Form, Fixed Bit, Long Packet Type Bit, Type-Specific Bits field, and Version field, which are obvious to those skilled in the art and thus will not be described in detail.

[0051] Additionally, the QUIC protocol header may include more or fewer fields than those shown in FIG. 2, and may have different lengths, sizes, etc. from those shown in FIG. 2.

[0052] Referring to FIG. 2, a QUIC signaling message format (220) is illustrated. FIG. 2 illustrates various QUIC signaling message formats (220), such as signaling messages for padding, PING, ACK, etc., in a table format, and the QUIC signaling message format (220) represents a signaling message format for the operation of the QUIC protocol.

[0053] According to one embodiment of the present disclosure, the QUIC signaling message format (220) may include a message format associated with a stream ID indicating characteristics of the QUIC protocol. In one example, the stream ID may be unique information included in the QUIC protocol. The remaining QUIC signaling message formats (220) are self-explanatory with respect to the names of the message formats described in FIG. 2, and thus a detailed description thereof will be omitted.

[0054] According to one embodiment, when a header (210) and a QUIC signaling message format (220) of the QUIC protocol are defined in the N3 interface and the N9 interface, the communication system can configure a PDU session using the QUIC protocol.

[0055] FIG. 3 illustrates an example of performing communication using the QUIC protocol according to one embodiment of the present disclosure.

[0056] When configuring a PDU session by replacing the GTP-U protocol within the user plane with the QUIC protocol, information within the PDU session configured based on the GTP-U protocol can be associated with unique information of the QUIC protocol. For example, information within the PDU session can be mapped to unique information of the QUIC protocol, such as the connection ID (e.g., UPF connection ID, gNB connection ID) and stream ID.

[0057] Referring to FIG. 3, a connection ID may be assigned to each PDU session to perform communication using the QUIC protocol. For example, for each PDU session, a gNB connection ID and a UPF connection ID corresponding to the PDU session may be assigned.

[0058] When performing communication using the QUIC protocol, multiple streams may be included in one PDU session. Each of the multiple streams may be controlled by quality of service (QoS). In one example, in order to perform communication using the QUIC protocol, stream IDs may be assigned to each QFI (QoS flow identifier) ​​indicating QoS in the PDU session. Referring to FIG. 3, when performing communication using the QUIC protocol, stream IDs 1 to 3 may be assigned to each of QFIs 1 to 3 in the PDU session to manage data. The stream ID may represent an identifier indicating each stream in the multiple streams.

[0059] According to one embodiment, streams are allocated according to QoS within a single PDU session, so that data transmission and reception can be controlled for each stream. Accordingly, even if data retransmission occurs within one of multiple streams, data transmission and reception can be maintained through streams in which retransmission did not occur within the same PDU session. In other words, connectivity can be maintained without data interruption according to stream management according to QoS within a single PDU session. In addition, when performing communication using the QUIC protocol, it can be easily managed for each data traffic even when using applications in XR, VR, or the metaverse, which have many differences in the characteristics of data traffic.

[0060] FIG. 4 illustrates a method of operating a PDU (packet data unit) session using the QUIC protocol according to one embodiment of the present disclosure.

[0061] There may be multiple ways to operate a PDU session based on the QUIC protocol added to the user plane protocol stack in a communication system.

[0062] FIG. 4 (a) describes a method of operating a PDU session by mapping streams and QFIs within a single QUIC connection. Referring to FIG. 4 (a), a single UE can be connected to a base station and a UPF entity using a single QUIC connection. That is, a single QUIC connection is allocated to a single terminal, and multiple streams can be included within a single QUIC connection. At this time, each QFI of the PDU session can be mapped to a stream of the QUIC connection and operated. For example, a QUIC connection between a first terminal (user equipment) (e.g., UE 1 of FIG. 4) and a connected base station and UPF entity can be a single QUIC connection. In addition, QFIs (e.g., QFIs 1 to 3) of a single QUIC connection can be mapped to each of multiple streams within QUIC, and each stream ID can be assigned. Additionally, the communication system can establish a QUIC connection between a base station and a UPF entity connected to UE 2 for a second terminal (e.g., UE 2 in FIG. 4) different from the first terminal as a single PDU session, and each QFI of the established PDU session can be mapped to a stream ID. In this case, each QFI mapped to each stream ID in the QUIC connection session can be managed for each data stream.

[0063] FIG. 4 (b) describes a method of operating a PDU session by allocating streams within a single QUIC connection to a UE. Referring to FIG. 4 (b), multiple UEs can be connected to a base station and a UPF entity using a single QUIC connection. That is, one QUIC connection can be allocated to multiple terminals, and one QUIC connection can include multiple streams. At this time, the QFI of the PDU session can be mapped to a stream of the QUIC connection and operated. For example, the QUIC connection between a base station and a UPF entity connected to a first terminal (e.g., UE 1 of FIG. 4) and a second terminal (e.g., UE 2 of FIG. 4) can be a single QUIC connection. For example, among the multiple streams within a single QUIC connection, streams 1 to 3 can be allocated to the first terminal, and among the multiple streams, streams 4 to 5 can be allocated to the second terminal.

[0064] FIG. 4 (c) describes a method of operating a PDU session by establishing a QUIC connection according to QFI. Referring to FIG. 4 (c), one UE can be connected to a base station and a UPF entity using multiple QUIC connections. That is, multiple QUIC connections are allocated to one terminal, and the multiple QUIC connections can be mapped to QFIs and operated. For example, multiple QUIC connections between a base station and a UPF entity connected to a first terminal (e.g., UE 1 of FIG. 4) can be multiple QUIC connections. Referring to FIG. 4, for the first terminal, three QUIC connections between the base station and the UPF can be mapped to QFIs 1 to 3, which indicate QoS, and operated, respectively.

[0065] According to the methods of (a) to (c) of Fig. 4, a QUIC connection between a base station and a UPF can be allocated to a terminal and operated.

[0066] Meanwhile, the method for establishing a QUIC connection (or a PDU session based on the QUIC protocol) may vary depending on where the QUIC connection is established (e.g., a UPF entity or a base station). Specific procedures for establishing and operating a QUIC connection are described in FIGS. 5 to 13.

[0067] FIG. 5 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 5 illustrates a procedure for creating a QUIC connection in a UPF entity to operate a PDU session, and mapping a stream and QFI within a single QUIC connection to establish and operate a PDU session.

[0068] Referring to FIG. 5, at operation 510, an SMF entity (509) may add information required for creating a QUIC connection to the SM (session management) policy. In one example, information that may be added to the SM policy is as follows.

[0069] - Number of streams in a QUIC connection

[0070] - A rule that maps QFI (QoS flow identifier) ​​and stream ID within QER (QoS (quality of service) enforcement rule)

[0071] - Information about the operation of PDU sessions

[0072] - Instruction information for QUIC connection

[0073] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0074] Information about the number of streams in a QUIC connection can indicate the number of streams in the QUIC connection to be mapped to QFIs of a PDU session based on the QUIC protocol. Information about a rule for mapping QFIs and stream IDs in a QER can indicate a rule for using a stream in the QUIC connection for a QFI of a PDU session. In one example, information about a rule for mapping QFIs and stream IDs can indicate information for mapping QFIs and stream IDs one-to-one (1:1) or many-to-one (N:1). For example, information about a rule for mapping QFIs and stream IDs can include information indicating mapping of stream ID 1 and QFI 1 and mapping of stream ID 2 and QFIs 2 and 3 for two streams in the QUIC connection.

[0075] On the other hand, if the information about the rules for mapping QFIs and stream IDs indicates that QFIs and stream IDs are mapped many-to-one, data may need to be transmitted through modification of the QUIC header, taking advantage of the nature of the QUIC protocol as a user-plane protocol.

[0076] Additionally, according to one embodiment, information about the operation of a PDU session may include information indicating which of several methods of establishing a PDU session will be used. For example, it may indicate a QUIC connection in a UPF entity or a QUIC connection in a base station. For example, information about the operation of a PDU session in FIG. 5 may include information indicating that a UPF entity immediately creates a QUIC connection in a QUIC layer after setting a UPF connection ID.

[0077] Additionally, according to one embodiment, the instruction information for a QUIC connection may include information indicating whether to use a pre-existing QUIC connection or to create a new QUIC connection. For example, the instruction information for a QUIC connection in FIG. 5 may include information indicating whether to create a new QUIC connection.

[0078] The SMF entity (509) can update the SM policy by adding the information necessary to operate the PDU session based on the QUIC protocol to the SM policy as above.

[0079] In operation 515, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF entity to set a connection ID (e.g., UPF connection ID or gNB connection ID) required when operating a QUIC connection. In one example, the SMF entity (509) of FIG. 5 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to set a UPF connection ID. In addition, the N4 session establishment request message may include information indicating whether to use a pre-created QUIC connection or to create a new QUIC connection based on information about PDU session operation added to the SM policy in operation 510. In one example, the SMF entity (509) of FIG. 5 may transmit an N4 session establishment request message to the UPF entity (507) including information indicating a new QUIC connection. The procedure for utilizing the pre-created QUIC connection is described in more detail in FIG. 11.

[0080] Additionally, the N4 session establishment request message may include information about the SM policy updated by the SMF entity (509) in operation 510. For example, the N4 session establishment request message may include the number of streams in the QUIC connection, rules for mapping QFIs and stream IDs, information about the operation of the PDU session, and instruction information about the QUIC connection.

[0081] In step 520, the UPF entity (507) selects a UPF connection ID based on an N4 session establishment request message received from the SMF entity (509), and in step 525, the UPF entity (507) can create a QUIC connection based on the selected UPF connection ID.

[0082] In operation 525, a QUIC connection may be created between a UPF entity (507) and a base station (503) in the QUIC layer of the QUIC protocol within the user plane protocol. At this time, the QUIC connection in the QUIC layer may be a QUIC connection created before the UPF connection ID is transmitted to the base station (503).

[0083] In operation 530, the UPF entity (507) may transmit an N4 session establishment response message in response to the N4 session establishment request message to the SMF entity (509). In one example, the N4 session establishment response message may include information about a UPF connection ID selected by the UPF entity (507) when creating a QUIC connection in operation 520. In addition, the N4 session establishment response message may include information about a gNB connection ID of a base station used when creating a QUIC connection between the UPF entity (507) and the base station (503) in operation 525. That is, the UPF entity (507) may transmit the N4 session establishment response message to the SMF entity (509) by including the UPF connection ID and the gNB connection ID.

[0084] At step 535, the SMF entity (509) and the AMF entity (505) may send and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) at step 510. For example, the N2 information may include information about the number of streams in the QUIC connection to be created, and rules for mapping QFIs and stream IDs. In addition, the N2 information may also include a UPF connection ID and a gNB connection ID. For example, the SMF entity (509) may include the UPF connection ID and gNB connection ID included in the N4 session establishment response message received from the UPF entity (507) in operation 530 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0085] In operation 545, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include the first N2 information in the Namf_Communication_N1N2MessageTransfer message received by the AMF entity (505) from the SMF entity (509) in operation 535.

[0086] In operation 550, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0087] In operation 555, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, for QFIs rejected by the base station (503) from the list of QFIs, mapping with a stream ID may not be performed. Additionally, for QFIs accepted by the base station (503) from the list of QFIs, mapping with a stream ID may be performed.

[0088] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0089] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. For example, as shown in (a) of FIG. 4, the base station connected to UE 1 can map each of the stream IDs to each of the QFIs within a QUIC connection based on the mapping rule within the N2 information received from the SMF entity via the AMF entity. The QFI mapped to each of the stream IDs can indicate a QFI allowed by the base station (503) among the list of QFIs received via operation 545. For example, the base station connected to UE 2 can map each of the stream IDs to each of the QFIs within a QUIC connection different from the QUIC connection used by UE 1 based on the mapping rule within the N2 information received from the SMF entity via the AMF entity.

[0090] In operation 560, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 545. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through the N2 interface between the base station and the AMF entity has been established. In one example, the N2 PDU session response message may include N2 information transmitted by the base station (503) to the SMF entity (509). In this case, the N2 information may include information in which the base station (503) maps a stream ID and a QFI. The information about the base station (503) mapping the stream ID and QFI may include the result of the base station (503) mapping the allowed QFI from the list of stream IDs and QFIs according to the mapping rule information in operation 555, and information about the rejected QFI from the list of QFIs. Meanwhile, the N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0091] At operation 570, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). In one example, the Nsmf_PDUSession_UpdateSMContext request message may include second N2 information included in the N2 PDU session response message received by the AMF entity (505) from the base station (503) at operation 560.

[0092] In step 575, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information on the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store the mapping result of the stream ID and the QFI through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0093] Through a procedure for establishing a PDU session based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using a QUIC connection based on information mapping the UPF connection ID, gNB connection ID, and stream IDs and QFIs of multiple streams within the QUIC connection.

[0094] FIG. 6 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 6 illustrates a procedure for establishing a PDU session by creating a QUIC connection in a UPF entity and allocating streams within a single QUIC connection to multiple UEs to operate the PDU session.

[0095] Referring to FIG. 6, operations 610 to 650 and operations 660 to 675 are the same as operations 510 to 550 and operations 560 to 575 of FIG. 5, respectively, and therefore, detailed descriptions thereof will be omitted.

[0096] In operation 655, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, for QFIs rejected by the base station (503) from the list of QFIs, mapping with a stream ID may not be performed. Additionally, for QFIs accepted by the base station (503) from the list of QFIs, mapping with a stream ID may be performed.

[0097] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0098] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. At this time, multiple streams can be allocated to multiple UEs within one QUIC connection. For example, as shown in (b) of FIG. 4, the base station can map each of the stream IDs within one QUIC connection to each of the QFIs within the QUIC connection based on the mapping rule within the N2 information received from the SMF entity through the AMF entity. The QFI mapped to each of the stream IDs can indicate a QFI allowed by the base station (503) among the list of QFIs received through operation 545. At this time, the streams mapped to each of the QFIs within one QUIC connection can be set to multiple terminals. For example, streams with stream IDs 1 to 5 within one QUIC connection can be mapped to QFIs 1 to 5 according to mapping rules, and among the mapped streams, streams corresponding to stream IDs 1 to 3 can be assigned to the first terminal, and streams corresponding to stream IDs 4 to 5 can be assigned to the second terminal.

[0099] Through the procedure for establishing a PDU session based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0100] Figures 5 and 6 illustrate a case where a QUIC connection between a UPF entity and a base station is created at the UPF entity. That is, Figures 5 and 6 illustrate a case where a QUIC connection occurs at the QUIC layer based on a UPF connection ID and a gNB connection ID received from the UPF entity before the SMF entity transmits N2 information to the base station.

[0101] FIG. 7 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 7 illustrates a procedure for establishing a PDU session by mapping a stream and QFI within a single QUIC connection, after a UPF connection ID set by a UPF entity is transmitted to a base station, creating a QUIC connection in the QUIC layer.

[0102] Referring to FIG. 7, in operation 710, an SMF entity (509) may add information necessary to establish a PDU session based on the QUIC protocol to the SM policy. In one example, the information that may be added to the SM policy is as follows.

[0103] - Number of streams in a QUIC connection

[0104] - A rule that maps QFI (QoS flow identifier) ​​and stream ID within QER (QoS (quality of service) enforcement rule)

[0105] - Information about the operation of PDU sessions

[0106] - Instruction information for QUIC connection

[0107] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0108] In one example, information about the operation of the PDU session of FIG. 7 may include information indicating the creation of a QUIC connection in the QUIC layer after the UPF connection ID set by the UPF entity is transmitted to the base station. In addition, in one example, the indication information about the QUIC connection of FIG. 7 may include information indicating the creation of a new QUIC connection.

[0109] In operation 715, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF to establish a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol. In one example, the SMF entity (509) of FIG. 7 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to establish a UPF connection ID.

[0110] In operation 720, the UPF entity (507) may select a UPF connection ID required for creating a QUIC connection between the UPF entity (507) and the base station (503) based on an N4 session establishment request message received from the SMF entity (509).

[0111] In operation 725, the UPF entity (507) may transmit an N4 session establishment response message to the SMF entity (509) in response to the N4 session establishment request message. In one example, the N4 session establishment response message may include information about the UPF connection ID selected by the UPF entity (507) in operation 720. At this time, in the case of FIG. 7, since the QUIC connection is not created in the UPF entity, the N4 session establishment response message may not include information about the gNB connection ID of the base station that can be used when creating the QUIC connection.

[0112] At step 730, the SMF entity (509) and the AMF entity (505) may transmit and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) at step 710. For example, the N2 information may include information about the number of streams in the QUIC connection to be created, and rules for mapping QFIs and stream IDs. Additionally, the N2 information may also include a UPF connection ID. For example, the SMF entity (509) may include the UPF connection ID included in the N4 session establishment response message received from the UPF entity (507) in operation 725 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0113] At operation 740, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include first N2 information received by the AMF entity (505) from the SMF entity (509) via the Namf_Communication_N1N2MessageTransfer message at operation 730.

[0114] In operation 745, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0115] In operation 750, a QUIC connection may be created between a UPF entity (507) and a base station (503) in the QUIC layer of the QUIC protocol within the user plane protocol. At this time, if a UPF connection ID is included in the information received by the base station (503) from the SMF entity (509) via the AMF entity (505), a QUIC connection may be created in the QUIC layer after the base station (503) receives the UPF connection ID. Meanwhile, the gNB connection ID of the base station may be used when the QUIC connection between the UPF entity (507) and the base station (503) is created.

[0116] In operation 755, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, for QFIs rejected by the base station (503) from the list of QFIs, mapping with a stream ID may not be performed. Additionally, for QFIs accepted by the base station (503) from the list of QFIs, mapping with a stream ID may be performed.

[0117] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0118] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. For example, as shown in (a) of FIG. 4, the base station connected to UE 1 can map each of the stream IDs to each of the QFIs within a QUIC connection based on the mapping rule within the N2 information received from the SMF entity via the AMF entity. The QFI mapped to each of the stream IDs can indicate a QFI allowed by the base station (503) among the list of QFIs received via operation 545. For example, the base station connected to UE 2 can map each of the stream IDs to each of the QFIs within a QUIC connection different from the QUIC connection used by UE 1 based on the mapping rule within the N2 information received from the SMF entity via the AMF entity.

[0119] In operation 760, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 740. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through an N2 interface between the base station and the AMF entity has been established. In addition, the N2 PDU session response message may include N2 information that the base station (503) transmits to the SMF entity (509). The N2 information that the base station (503) intends to transmit to the SMF entity (509) may include information that the base station (503) maps a stream ID and a QFI. Information about the base station (503) mapping stream IDs and QFIs may include information about the results of the base station (503) mapping QFIs allowed from the list of stream IDs and QFIs according to the mapping rules in operation 755 and information about QFIs rejected from the list of QFIs. In addition, N2 information may also include information about the gNB connection ID used when the QUIC connection generated by the base station (503) is created. Meanwhile, N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0120] At operation 770, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). In one example, the Nsmf_PDUSession_UpdateSMContext request message may include the second N2 information within the N2 PDU session response message received by the AMF entity (505) from the base station (503) at operation 760.

[0121] At step 775, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information regarding the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information and a gNB connection ID received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store the mapping result of the stream ID and QFI and the gNB connection ID through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0122] Through the procedure for establishing the PDU session described above, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0123] FIG. 8 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 8 illustrates a procedure for establishing a PDU session by creating a QUIC connection in the QUIC layer after a UPF connection ID set by a UPF entity is transmitted to a base station and allocating streams within a single QUIC connection to multiple UEs.

[0124] Referring to FIG. 8, operations 810 to 850 and operations 860 to 875 are the same as operations 710 to 750 and operations 760 to 775 of FIG. 7, respectively, and therefore, detailed descriptions thereof will be omitted.

[0125] In operation 855, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, for QFIs rejected by the base station (503) from the list of QFIs, mapping with a stream ID may not be performed. Additionally, for QFIs accepted by the base station (503) from the list of QFIs, mapping with a stream ID may be performed.

[0126] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0127] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. At this time, multiple streams can be allocated to multiple UEs within one QUIC connection. For example, as shown in (b) of FIG. 4, the base station can map each of the stream IDs within one QUIC connection to each of the QFIs within the QUIC connection based on the mapping rule within the N2 information received from the SMF entity through the AMF entity. At this time, the streams mapped to each QFI within one QUIC connection can be set to multiple terminals. For example, streams of stream ID 1 to 5 within one QUIC connection can be mapped to each of QFIs 1 to 5 according to the mapping rule, and among the mapped streams, streams corresponding to stream ID 1 to 3 can be allocated to a first terminal, and streams corresponding to stream ID 4 to 5 can be allocated to a second terminal.

[0128] Through the procedure for establishing a PDU session based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0129] Figures 7 and 8 illustrate a case where a QUIC connection between a UPF entity and a base station is created at the base station. That is, Figures 7 and 8 illustrate a case where a QUIC connection occurs at the QUIC layer after an SMF entity transmits N2 information to the base station and the base station receives the UPF connection ID included in the N2 information.

[0130] FIG. 9 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 9 illustrates a procedure for establishing a PDU session by mapping a stream and QFI within a single QUIC connection when a QUIC connection is not created in the QUIC layer but is created using handshake information in a 3GPP network.

[0131] Referring to FIG. 9, in operation 910, the SMF entity (509) may add information necessary to establish a PDU session based on the QUIC protocol to the SM policy.

[0132] As an example, information that can be added to an SM policy includes:

[0133] - Number of streams in a QUIC connection

[0134] - A rule that maps QFI (QoS flow identifier) ​​and stream ID within QER (QoS (quality of service) enforcement rule)

[0135] - Information about the operation of PDU sessions

[0136] - Instruction information for QUIC connection

[0137] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0138] In one example, information about the operation of the PDU session of FIG. 9 may include information indicating the creation of a QUIC connection within the 3GPP network of the base station.

[0139] The instruction information for a QUIC connection may include information indicating whether to use a pre-existing QUIC connection or to create a new QUIC connection. For example, the instruction information for a QUIC connection in FIG. 9 may include information indicating whether to create a new QUIC connection.

[0140] The SMF entity (509) can update the SM policy by adding the information necessary to operate the PDU session based on the QUIC protocol to the SM policy as above.

[0141] In operation 915, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF to establish a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol. In one example, the SMF entity (509) of FIG. 9 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to establish a UPF connection ID.

[0142] In operation 920, the UPF entity (507) may select a UPF connection ID required for creating a QUIC connection between the UPF entity (507) and the base station (503) based on an N4 session establishment request message received from the SMF entity (509).

[0143] In operation 925, the UPF entity (507) may transmit an N4 session establishment response message to the SMF entity (509) in response to the N4 session establishment request message. In one example, the N4 session establishment response message may include information about the UPF connection ID selected by the UPF entity (507) in operation 920. In this case, in the case of FIG. 9, the N4 session establishment response message may not include information about the gNB connection ID of the base station that may be used when creating a QUIC connection.

[0144] According to one embodiment, the N4 session establishment response message in FIG. 9 may additionally include information required for a handshake procedure in addition to the UPF connection ID. The handshake procedure may refer to a procedure for setting up link parameters of a communication link to allow communication targets to communicate reliably through a direct link. Information required for the handshake procedure that may be included in the N4 session establishment response message may include, but is not limited to, the following information.

[0145] - Initial Information: May include the source connection ID and client Hello message of the UPF entity.

[0146] - CRYPTO: Can include a cryptographic handshake message.

[0147] - 0-RTT Information: Can contain data required for 0-RTT handshake connection.

[0148] At operation 930, the SMF entity (509) and the AMF entity (505) may transmit and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) at operation 910. For example, the N2 information may include information about the number of streams in the QUIC connection to be created, and rules for mapping QFIs and stream IDs. In addition, the N2 information may also include a UPF connection ID and information required for the handshake procedure (e.g., Initial Information, CRYPTO, 0-RTT Information, etc.). For example, the SMF entity (509) may include the UPF connection ID and information required for the handshake procedure included in the N4 session establishment response message received from the UPF entity (507) in operation 925 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0149] In operation 940, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include first N2 information received by the AMF entity (505) from the SMF entity (509) via a Namf_Communication_N1N2MessageTransfer message.

[0150] In operation 945, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0151] In operation 950, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, mapping with a stream ID may not be performed for QFIs rejected by the base station (503) from the list of QFIs. Additionally, mapping with a stream ID may be performed for QFIs accepted by the base station (503) from the list of QFIs.

[0152] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0153] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. For example, as shown in (a) of FIG. 4, the base station connected to UE 1 can map each of the stream IDs to each of the QFIs within a QUIC connection based on the mapping rule within the N2 information received from the SMF entity via the AMF entity. For example, the base station connected to UE 2 can map each of the stream IDs to each of the QFIs within the QUIC connection different from the QUIC connection used by UE 1 based on the mapping rule within the N2 information received from the SMF entity via the AMF entity.

[0154] According to one embodiment, in FIG. 9, the base station (503) may create a QUIC connection within 3GPP based on the UPF connection ID and information required for handshake received from the SMF entity (509) via the AMF entity (505). In this case, the QUIC connection may not be created in the QUIC layer, but rather, the QUIC connection may be created within 3GPP while the information required for the QUIC connection is transmitted to the base station (503).

[0155] In operation 955, the base station (503) may select a gNB connection ID set for a QUIC connection based on a QUIC connection generated within 3GPP. In one example, the selected gNB connection ID may be included in Handshake Information, which indicates information about a handshake associated with the QUIC connection.

[0156] In operation 960, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 940. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through an N2 interface between the base station and the AMF entity has been established. In addition, the N2 PDU session response message may include N2 information transmitted by the base station (503) to the SMF entity (509). The N2 information transmitted from the base station (503) to the SMF entity (509) may include information in which the base station (503) maps a stream ID and a QFI. The information that the base station (503) maps the stream ID and QFI may include the result of the base station (503) mapping the stream ID and QFI according to the mapping rule in operation 950. In addition, the N2 information may include handshake information associated with the QUIC connection in relation to the QUIC connection created within 3GPP. The handshake information associated with the QUIC connection may include the following information, but is not limited thereto.

[0157] - Initial Information: May include a server Hello message.

[0158] - CRYPTO: Can include a cryptographic handshake message.

[0159] - 1-RTT Information: Can include data required for 1-RTT handshake connection.

[0160] - Handshake Information: The gNB connection ID selected by the base station when creating a QUIC connection within 3GPP may be included.

[0161] - ACK frame: May contain information to confirm receipt of the client Hello message.

[0162] Information about the gNB connection ID selected by the base station (503) may also be included. Meanwhile, the N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0163] At operation 970, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). In one example, the Nsmf_PDUSession_UpdateSMContext request message may include second N2 information in an N2 PDU session response message received by the AMF entity (505) from the base station (503).

[0164] At step 975, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information regarding the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information (e.g., a mapping result of stream ID and QFI, handshake information associated with a QUIC connection) received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store the result of mapping the stream ID and QFI and the handshake information associated with the QUIC connection through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0165] Through the PDU session establishment procedure based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0166] Fig. 10 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, Fig. 10 illustrates a procedure for establishing a PDU session by allocating streams within a single QUIC connection to multiple UEs when a QUIC connection is not created in the QUIC layer and a QUIC connection is created using handshake information in a 3GPP network.

[0167] Referring to FIG. 10, operations 1010 to 1045 and operations 1060 to 1075 are identical to operations 910 to 945 and operations 960 to 975 of FIG. 9, respectively, and therefore, detailed descriptions thereof will be omitted.

[0168] In step 1050, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, mapping with a stream ID may not be performed for QFIs rejected by the base station (503) from the list of QFIs. Additionally, mapping with a stream ID may be performed for QFIs accepted by the base station (503) from the list of QFIs.

[0169] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0170] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. For example, as shown in (b) of FIG. 4, the base station can map each of the stream IDs within one QUIC connection to each of the QFIs within the QUIC connection based on the mapping rule within the N2 information received from the SMF entity via the AMF entity. At this time, the streams mapped to each QFI within one QUIC connection can be set to multiple terminals. For example, the streams of stream ID 1 to 5 within one QUIC connection can be mapped to each of the QFIs 1 to 5 according to the mapping rule, and the streams corresponding to stream ID 1 to 3 among the mapped streams can be assigned to the first terminal, and the streams corresponding to stream ID 4 to 5 can be assigned to the second terminal.

[0171] According to one embodiment, the base station (503) in FIG. 10 may create a QUIC connection within 3GPP based on the UPF connection ID and information required for handshake received in the previous operation. In this case, the QUIC connection is not created in the QUIC layer, but rather, the QUIC connection may be created within 3GPP while the information required for the QUIC connection is transmitted to the base station (503).

[0172] In operation 1055, the base station (503) may select a gNB connection ID set for a QUIC connection based on a QUIC connection generated within 3GPP. In one example, the selected gNB connection ID may be included in Handshake Information, which indicates information about a handshake associated with the QUIC connection.

[0173] Through the PDU session establishment procedure based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0174] Figures 9 and 10 illustrate a case where an SMF entity transmits handshake information necessary for creating a QUIC connection within 3GPP to a base station. That is, Figures 9 and 10 illustrate a case where a QUIC connection is created within 3GPP rather than the QUIC layer by having an SMF entity transmit information necessary for a QUIC handshake to a base station.

[0175] FIG. 11 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 11 illustrates a procedure for establishing a PDU session by utilizing an existing QUIC connection to operate a PDU session and allocating streams within a single QUIC connection to multiple UEs.

[0176] Referring to FIG. 11, in operation 1110, an SMF entity (509) may add information necessary to establish a PDU session based on the QUIC protocol to the SM policy. In one example, the information that may be added to the SM policy is as follows.

[0177] - Number of streams in a QUIC connection

[0178] - Rule for mapping QFI and stream ID within QER (mapping rule)

[0179] - Information about the operation of PDU sessions

[0180] - Instruction information for QUIC connection

[0181] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0182] In one example, information about the operation of a PDU session added to FIG. 11 may include information indicating that a pre-created QUIC connection should be used.

[0183] The SMF entity (509) can update the SM policy by adding the information necessary to operate the PDU session based on the QUIC protocol to the SM policy as above.

[0184] In operation 1115, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF to establish a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol. In one example, the SMF entity (509) of FIG. 11 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to establish a UPF connection ID and a gNB connection ID based on an existing QUIC connection.

[0185] In operation 1120, the UPF entity (507) can check information about the UPF connection ID and gNB connection ID set in the pre-created QUIC connection based on information indicating the pre-created QUIC connection included in the N4 session establishment request message received from the SMF entity (509).

[0186] In operation 1125, the UPF entity (507) may transmit an N4 session establishment response message to the SMF entity (509) in response to the N4 session establishment request message. In one example, the N4 session establishment response message may include information about the UPF connection ID and the gNB connection ID set for the pre-created QUIC connection confirmed by the UPF entity (507) in operation 1120. That is, the UPF entity (507) may transmit the N4 session establishment response message to the SMF entity (509) including the UPF connection ID and the gNB connection ID for the pre-created QUIC connection indicated by the N4 session establishment request message of operation 1115.

[0187] At operation 1130, the SMF entity (509) and the AMF entity (505) may transmit and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) at operation 1110. For example, the N2 information may include information about the number of streams in the QUIC connection, information about rules for mapping QFIs and stream IDs, and information indicating a pre-created QUIC connection. In addition, the N2 information may also include a UPF connection ID and a gNB connection ID. For example, the SMF entity (509) may include the UPF connection ID and gNB connection ID included in the N4 session establishment response message received from the UPF entity (507) in operation 1125 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0188] In operation 1140, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include N2 information in a Namf_Communication_N1N2MessageTransfer message received by the AMF entity (505) from the SMF entity (509).

[0189] In operation 1145, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0190] In operation 1150, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, mapping with a stream ID may not be performed for QFIs rejected by the base station (503) from the list of QFIs. Additionally, mapping with a stream ID may be performed for QFIs accepted by the base station (503) from the list of QFIs.

[0191] The base station (503) can generate a stream ID based on information about the number of streams to be generated within the QUIC connection included in the received N2 information. For example, the base station (503) can generate as many stream IDs as indicated in response to information about the number of streams to be generated included in the first N2 information received from the SMF entity (509).

[0192] In addition, the base station (503) can map the generated stream ID to the QFI based on the information about the rule for mapping the QFI and stream ID included in the received N2 information. At this time, multiple streams can be allocated to multiple UEs within one QUIC connection. For example, as shown in (b) of FIG. 4, the base station can map each of the stream IDs within one QUIC connection to each of the QFIs within the QUIC connection based on the mapping rule within the N2 information received from the SMF entity through the AMF entity. At this time, the streams mapped to each QFI within one QUIC connection can be set to multiple terminals. For example, streams of stream ID 1 to 5 within one QUIC connection can be mapped to each of QFIs 1 to 5 according to the mapping rule, and among the mapped streams, streams corresponding to stream ID 1 to 3 can be allocated to a first terminal, and streams corresponding to stream ID 4 to 5 can be allocated to a second terminal.

[0193] In operation 1155, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 545. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through the N2 interface between the base station and the AMF entity has been established. In one example, the N2 PDU session response message may include N2 information transmitted by the base station (503) to the SMF entity (509). The N2 information transmitted from the base station (503) to the SMF entity (509) may include information in which the base station (503) maps a stream ID and a QFI. The information that the base station (503) maps the stream ID and QFI may include the result of mapping the stream ID and QFI according to the mapping rule in the base station (503) operation 1155. Meanwhile, the N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0194] At operation 1165, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). The Nsmf_PDUSession_UpdateSMContext request message may include the second N2 information received by the AMF entity (505) from the base station (503) at operation 1155.

[0195] At step 1170, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the SMS UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information on the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store the mapping result of the stream ID and the QFI through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0196] Through the PDU session establishment procedure based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, the gNB connection ID, and the information mapping the stream IDs and QFIs of multiple streams within the QUIC connection.

[0197] FIG. 12 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 12 illustrates a procedure for creating a QUIC connection in the QUIC layer after a UPF connection ID established by a UPF entity is transmitted to a base station, and then mapping multiple QUIC connections according to QFI to operate a PDU session.

[0198] Referring to FIG. 12, at operation 1210, the SMF entity (509) may add information necessary to establish a PDU session based on the QUIC protocol to the SM policy. In one example, the information that may be added to the SM policy is as follows.

[0199] - Number of streams in a QUIC connection

[0200] - Rule for mapping QFI and stream ID within QER (mapping rule)

[0201] - Information about the operation of PDU sessions

[0202] - Instruction information for QUIC connection

[0203] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0204] In one example, the information regarding the operation of the PDU session of FIG. 12 may include information indicating the creation of a QUIC connection at the base station. Furthermore, in one example, the instruction information regarding the QUIC connection of FIG. 12 may include information indicating the creation of a new QUIC connection. The instruction information regarding the QUIC connection of FIG. 12 may also include information indicating the creation of multiple QUIC connections.

[0205] The SMF entity (509) can update the SM policy by adding the information necessary to operate the PDU session based on the QUIC protocol to the SM policy as above.

[0206] In operation 1215, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF to establish a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol. The SMF entity (509) of FIG. 12 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to establish a UPF connection ID. At this time, the information requesting the establishment of the UPF connection ID may indicate information requesting a UPF connection ID corresponding to a plurality of QUIC connections to be generated according to the number of multiple streams.

[0207] In operation 1220, the UPF entity (507) may select a UPF connection ID required for creating a QUIC connection between the UPF entity (507) and the base station (503) based on an N4 session establishment request message received from the SMF entity (509).

[0208] In operation 1225, the UPF entity (507) may transmit an N4 session establishment response message to the SMF entity (509) in response to the N4 session establishment request message. In one example, the N4 session establishment response message may include information about the UPF connection ID selected by the UPF entity (507) in operation 1220. At this time, in the case of FIG. 12, since the QUIC connection is not created in the UPF entity, the N4 session establishment response message may not include information about the gNB connection ID of the base station that can be used when creating the QUIC connection.

[0209] At operation 1230, the SMF entity (509) and the AMF entity (505) may send and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) at operation 1210. For example, the N2 information may include information about the number of streams in the QUIC connection to be created, and rules for mapping QFIs and stream IDs. Additionally, the N2 information may also include a UPF connection ID. For example, the SMF entity (509) may include the UPF connection ID included in the N4 session establishment response message received from the UPF entity (507) in operation 1225 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0210] At operation 1240, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include the first N2 information in the Namf_Communication_N1N2MessageTransfer message received by the AMF entity (505) from the SMF entity (509) at operation 1230.

[0211] In operation 1245, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0212] In operation 1250, a QUIC connection may be created between a UPF entity (507) and a base station (503) in a QUIC layer of a QUIC protocol in a user plane protocol. At this time, if a UPF connection ID is included in information transmitted to the base station (503) from an SMF entity (509) via an AMF entity (505), a QUIC connection may be created in the QUIC layer after the base station (503) receives the UPF connection ID. In one example, the base station (503) may allow or deny some QFIs from a list of QFIs based on N2 information received from the SMF entity (509). In one example, a QUIC connection may not be created for a QFI that is denied by the base station (503) from the list of QFIs. In addition, a QUIC connection may be created for a QFI that is allowed by the base station (503) from the list of QFIs. The generated QUIC connection can correspond to the number of preset streams, and there may be multiple QUIC connections generated at this time. Meanwhile, when a QUIC connection between a UPF entity (507) and a base station (503) is generated, the gNB connection ID of the base station may be used. If there are multiple QUIC connections generated, each QUIC connection may have a set of associated UPF connection IDs and gNB connection IDs.

[0213] In operation 1255, the base station (503) can map the UPF connection ID and gNB connection ID set of the generated QUIC connection and each QFI. For example, the base station (503) can map the UPF connection ID and gNB connection ID set of the generated QUIC connection and each QFI corresponding to each stream ID in the mapping rule of the stream ID and QFI previously received from the SMF entity. When there are multiple generated QUIC connections, the base station (503) can map the UPF connection ID and gNB connection ID set corresponding to each QUIC connection to the QFI identified in operation 1250. For example, as in (c) of FIG. 4, a PDU session of UE 1 can be generated and operated by a QUIC connection corresponding to QFI 1 to 3 indicating QoS between the base station connected to UE 1 and the UPF. A total of three QUIC connections are created corresponding to each of QFIs 1 to 3, and each QFI and QUIC connection are mapped so that the PDU session of UE 1 can be operated.

[0214] In operation 1260, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 1240. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through an N2 interface between the base station and the AMF entity has been established. In addition, the N2 PDU session response message may include N2 information transmitted by the base station (503) to the SMF entity (509). The N2 information transmitted from the base station (503) to the SMF entity (509) may include information on which the base station (503) maps a QUIC connection and QFI. Information about the QUIC connection and QFI mapping by the base station (503) may include, for example, the result of mapping the UPF connection ID and gNB connection ID set and QFI corresponding to each of the plurality of QUIC connections in operation 1255 by the base station (503). In addition, the N2 information may also include information about the gNB connection ID used when the QUIC connection generated by the base station (503) is generated. For example, when multiple QUIC connections are generated, there may also be multiple gNB connection IDs. Meanwhile, the N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0215] At operation 1270, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). The Nsmf_PDUSession_UpdateSMContext request message may include the second N2 information received by the AMF entity (505) from the base station (503) at operation 1260.

[0216] At step 1275, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information regarding the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information and a gNB connection ID received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store a set of UPF connection IDs and gNB connection IDs corresponding to a QUIC connection and a mapping result of QFI and a gNB connection ID through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0217] Through the PDU session establishment procedure based on the aforementioned QUIC protocol, the SMF entity (509) can perform communication using the QUIC connection based on the UPF connection ID, gNB connection ID, and information mapping the QUIC connection and QFI.

[0218] FIG. 13 illustrates an operation for establishing a PDU session according to one embodiment of the present disclosure. Specifically, FIG. 13 illustrates a procedure for operating a PDU session by mapping multiple QUIC connections according to QFI when a QUIC connection is not created in the QUIC layer and multiple QUIC connections are created using handshake information within 3GPP.

[0219] Referring to FIG. 13, at operation 1210, the SMF entity (509) may add information necessary to establish a PDU session based on the QUIC protocol to the SM policy. In one example, the information that may be added to the SM policy is as follows.

[0220] - Number of streams in a QUIC connection

[0221] - Rule for mapping QFI and stream ID within QER (mapping rule)

[0222] - Information about the operation of PDU sessions

[0223] - Instruction information for QUIC connection

[0224] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0225] In one example, the information regarding the operation of the PDU session of FIG. 13 may include information indicating the creation of a QUIC connection at the base station. Furthermore, in one example, the instruction information regarding the QUIC connection of FIG. 13 may include information indicating the creation of a new QUIC connection. The instruction information regarding the QUIC connection of FIG. 13 may also include information indicating the creation of multiple QUIC connections.

[0226] The SMF entity (509) can update the SM policy by adding the information necessary to operate the PDU session based on the QUIC protocol to the SM policy as above.

[0227] In operation 1315, the SMF entity (509) may transmit an N4 session establishment request message to the UPF entity (507) based on the updated SM policy. The N4 session establishment request message may include information requesting the UPF to establish a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol. In one example, the SMF entity (509) of FIG. 13 may transmit an N4 session establishment request message including information requesting the UPF entity (507) to establish a UPF connection ID. At this time, the information requesting the establishment of the UPF connection ID may indicate information requesting a UPF connection ID corresponding to a plurality of QUIC connections to be generated according to the number of a plurality of streams.

[0228] In operation 1320, the UPF entity (507) may select a UPF connection ID required for creating a QUIC connection between the UPF entity (507) and the base station (503) based on an N4 session establishment request message received from the SMF entity (509).

[0229] In operation 1325, the UPF entity (507) may transmit an N4 session establishment response message to the SMF entity (509) in response to the N4 session establishment request message. In one example, the N4 session establishment response message may include information about the UPF connection ID selected by the UPF entity (507) in operation 1220. At this time, in the case of FIG. 13, since the QUIC connection is not created in the UPF entity, the N4 session establishment response message may not include information about the gNB connection ID of the base station that can be used when creating the QUIC connection.

[0230] According to one embodiment, the N4 session establishment response message in FIG. 13 may additionally include information required for a handshake procedure in addition to the UPF connection ID. The handshake procedure may refer to a procedure for setting up link parameters of a communication link to allow communication targets to communicate reliably through a direct link. Information required for the handshake procedure that may be included in the N4 session establishment response message may include, but is not limited to, the following information.

[0231] - Initial Information: May include the source connection ID and client Hello message of the UPF entity.

[0232] - CRYPTO: Can include a cryptographic handshake message.

[0233] - 0-RTT Information: Can contain data required for 0-RTT handshake connection.

[0234] Also, according to one embodiment, the SMF entity (509) and the AMF entity (505) may send and receive a Namf_Communication_N1N2MessageTransfer message. In one example, the Namf_Communication_N1N2MessageTransfer message may include N2 information to be transmitted from the SMF entity (509) to the base station (503). The N2 information may include information in the SM policy updated by the SMF entity (509) in operation 1310. For example, the N2 information may include information about the number of streams in the QUIC connection to be created, and rules for mapping QFIs and stream IDs. In addition, the N2 information may also include a UPF connection ID and information required for the handshake procedure (e.g., Initial Information, CRYPTO, 0-RTT Information, etc.). For example, the SMF entity (509) may include the UPF connection ID and information required for the handshake procedure included in the N4 session establishment response message received from the UPF entity (507) in operation 925 in N2 information and transmit it to the base station (503). Meanwhile, the N2 information transmitted from the SMF entity (509) to the base station (503) may be referred to as first N2 information.

[0235] In operation 1340, the AMF entity (505) may transmit an N2 PDU session request message including information requesting an N2 PDU session to the base station (503). In one example, the N2 PDU session request message may include the first N2 information in a Namf_Communication_N1N2MessageTransfer message received by the AMF entity (505) from the SMF entity (509).

[0236] In operation 1345, the base station (503) may exchange specific signaling with respect to information received from the terminal (501) and the SMF entity (509). In one example, the base station (503) may transmit information received from the SMF entity (509) to the terminal via the AMF entity (505).

[0237] In operation 1350, the base station (503) may receive a list of QFIs based on the N2 information received from the SMF entity (509). The base station (503) may allow or reject some QFIs from the list of received QFIs. In one example, for QFIs rejected by the base station (503) from the list of QFIs, mapping with a stream ID may not be performed. Additionally, for QFIs accepted by the base station (503) from the list of QFIs, mapping with a stream ID may be performed.

[0238] According to one embodiment, the base station (503) may create a QUIC connection within 3GPP based on the UPF connection ID and information required for handshake received from the SMF entity (509) via the AMF entity (505). In this case, the QUIC connection may not be created in the QUIC layer, but may be created within 3GPP while the information required for the QUIC connection is transmitted to the base station (503). The created QUIC connection may correspond to the number of preset streams, and the number of created QUIC connections may be multiple. Meanwhile, the gNB connection ID of the base station may be used when a QUIC connection is created between the UPF entity (507) and the base station (503). The base station (503) may select the gNB connection ID set for the QUIC connection based on the QUIC connection created within 3GPP. If multiple QUIC connections are created, each QUIC connection may have an associated set of UPF connection IDs and gNB connection IDs.

[0239] In operation 1355, the base station (503) can map each gNB connection ID and QFI of the QUIC connection generated within 3GPP. For example, the base station (503) can map each gNB connection ID and QFI of the generated QUIC connection corresponding to each stream ID in the mapping rule of the stream ID and QFI previously received from the SMF entity. When there are multiple generated QUIC connections, the base station (503) can map a set of gNB connection IDs corresponding to each QUIC connection to the QFI identified in operation 1350. For example, as shown in (c) of FIG. 4, a PDU session of UE 1 can be generated and operated by a QUIC connection corresponding to QFIs 1 to 3 indicating QoS between the base station connected to UE 1 and the UPF. A total of three QUIC connections are created corresponding to each of QFIs 1 to 3, and each QFI and QUIC connection are mapped so that the PDU session of UE 1 can be operated.

[0240] In operation 1360, the base station (503) may transmit an N2 PDU session response message to the AMF entity (505). The N2 PDU session response message may be a message in response to the N2 PDU session request message received by the base station (503) from the AMF entity (505) in operation 1340. For example, the N2 PDU session response message may include information indicating that a PDU session transmitted and received through the N2 interface between the base station and the AMF entity has been established. In addition, the N2 PDU session response message may include N2 information transmitted by the base station (503) to the SMF entity (509). The N2 information transmitted from the base station (503) to the SMF entity (509) may include information indicating that the base station (503) maps a gNB connection ID to a QFI. The information that the base station (503) maps the QUIC connection and QFI may include, for example, the result of the base station (503) mapping the gNB connection ID and QFI corresponding to each of the multiple QUIC connections in operation 1355. In addition, the N2 information may include handshake information associated with the QUIC connection in relation to the QUIC connection generated within 3GPP. The handshake information associated with the QUIC connection may include the following information, but is not limited thereto.

[0241] - Initial Information: May include a server Hello message.

[0242] - CRYPTO: Can include a cryptographic handshake message.

[0243] - 1-RTT Information: Can include data required for 1-RTT handshake connection.

[0244] - Handshake Information: May include the gNB connection ID selected by the base station when creating a QUIC connection within 3GPP.

[0245] - ACK frame: May contain information to confirm receipt of the client Hello message.

[0246] Information about the gNB connection ID selected by the base station (503) may also be included. Meanwhile, the N2 information transmitted from the base station (503) to the SMF entity (509) may be referred to as second N2 information.

[0247] In operation 1370, the AMF entity (505) may send an Nsmf_PDUSession_UpdateSMContext request message to the SMF entity (509). The Nsmf_PDUSession_UpdateSMContext request message may include second N2 information received by the AMF entity (505) from the base station (503).

[0248] At step 1375, the SMF entity (509) and the UPF entity (507) can perform a procedure for modifying the established N4 session. Specifically, the SMF entity (509) can transmit an N4 session modification request message to the UPF entity (507), and the UPF entity (507) can transmit an N4 session modification response message including information regarding the result of modifying the N4 session in response thereto. In one example, the N4 session modification request message can include N2 information (e.g., a mapping result of gNB connection ID and QFI, handshake information associated with a QUIC connection) received by the SMF entity (509) from the base station (503) via the AMF entity (505). The UPF entity (507) can store the result of mapping the stream ID and QFI and the handshake information associated with the QUIC connection through the N2 information included in the N4 session modification request message received from the SMF entity (509).

[0249] FIG. 14 illustrates an operation of releasing a PDU session according to one embodiment of the present disclosure. Specifically, it illustrates an operation of releasing a QUIC connection (or a PDU session based on the QUIC protocol).

[0250] According to one embodiment, a procedure for releasing a PDU session based on the QUIC protocol may differ depending on whether one QUIC connection operates a PDU session associated with one terminal (e.g., the PDU session operating method of FIG. 4 (a) and FIG. 4 (c)) or one QUIC connection operates PDU sessions associated with multiple terminals (e.g., the PDU session operating method of FIG. 4 (b)). Operations 1405 to 1480 of FIG. 14 may be operations within a PDU session release procedure in a basic 5G communication network. Operations 1485 and 1490 operate as different embodiments and do not operate together.

[0251] According to one embodiment, when operating a PDU session associated with one terminal per one QUIC connection (for example, the PDU session operating method of FIG. 4 (a) and FIG. 4 (c)), a method for releasing a PDU session can be subdivided into two methods. Specifically, a first PDU session release method may be a method for terminating a QUIC connection in a QUIC layer. A second PDU session release method may be a method for including connection close information for terminating a QUIC connection in an N4 session release response message transmitted by a UPF entity to an SMF entity. The N4 session release response message may be a message in response to an N4 session release request message received by the UPF entity from the SMF entity.

[0252] The first PDU session release method may mean, for example, a method of terminating a QUIC connection composed of a UPF connection ID and a gNB connection ID associated with a released PDU session in the QUIC layer after all basic PDU session release procedures (e.g., operations 1405 to 1480) are completed. For example, in FIG. 14, the UPF entity (507) may instruct termination of a QUIC connection in the QUIC layer in operation 1485 after the basic PDU session release procedures of operations 1405 to 1480 are completed. For example, in the case of releasing a PDU session in FIG. 5, after the basic PDU session release procedure is completed, the UPF entity (507) may instruct termination of one QUIC connection composed of a UPF connection ID and a gNB connection ID in the QUIC layer.

[0253] Meanwhile, in case of multiple QUIC connections, the first PDU session release method may mean, for example, a method of terminating all QUIC connections composed of a set of UPF connection IDs and gNB connection IDs associated with the released PDU sessions in the QUIC layer after all basic PDU session release procedures are completed. For example, in case of releasing the PDU session of FIG. 12, after the basic PDU session release procedure is completed, the UPF entity (507) may instruct the termination of multiple QUIC connections composed of a set of UPF connection IDs and gNB connection IDs in the QUIC layer.

[0254] The second PDU session release method may mean, for example, a method in which information transmitted and received in a basic PDU session release procedure includes information indicating termination of a QUIC connection. For example, referring to FIG. 14, when a UPF entity (507) transmits an N4 session release response message in response to an N4 session release request message (operation 1405) received from an SMF entity (509) in operation 1410, the UPF entity (507) may include information for terminating a QUIC connection in the N4 session release response message. The information for terminating a QUIC connection may mean connection close information that may terminate the QUIC connection. Thereafter, the SMF entity (509) may transmit the connection close information included in the N4 session release response message from the AMF entity (505) to the base station (503) through operations 1415 to 1435. The base station (503) that has received the connection close information from the UPF entity (507) can terminate the QUIC connection and transmit the connection close information, which indicates the termination of the QUIC connection of the base station (503), to the SMF entity (509) through operations 1445 to 1450. Thereafter, the SMF entity (509) can transmit the connection close information to the UPF entity (507).

[0255] Meanwhile, in case of multiple QUIC connections, the second PDU session release method may mean, for example, a method in which information indicating termination of all QUIC connections to be released is included in the information transmitted and received in the basic PDU session release procedure. For example, in case of releasing the PDU session of FIG. 12, information indicating termination of multiple QUIC connections composed of a set of UPF connection IDs and gNB connection IDs may be included in the information transmitted and received in the basic PDU session release procedure.

[0256] According to one embodiment, when one QUIC connection operates a PDU session associated with multiple terminals (e.g., the PDU session operating method of (b) of FIG. 4), a method of releasing a PDU session may mean a method of deleting a stream ID of a UPF connection ID and a gNB connection ID corresponding to a QUIC connection to be released in the QUIC layer after all basic PDU session release procedures (e.g., operations 1405 to 1480) are completed. For example, in FIG. 14, after the basic PDU session release procedures of operations 1405 to 1480 are completed, the UPF entity (507) may instruct deletion of a stream ID of a UPF connection ID and a gNB connection ID corresponding to a QUIC connection in the QUIC layer in operation 1490. For example, when releasing a PDU session in FIG. 6, after the basic PDU session release procedure is completed, the UPF entity (507) can instruct the deletion of the UPF connection ID and gNB connection ID in the QUIC layer.

[0257] FIG. 15 illustrates an operation for modifying a PDU session according to one embodiment of the present disclosure. Operations 1510 to 1535 and operations 1550 to 1590 of FIG. 15 may also be operations performed in a general PDU session modification procedure.

[0258] When a QFI within a QER changes, the SM policy can update information including the mapping rules for the changed stream and QFI, as well as the number of changed streams. The procedure for changing a PDU session varies depending on the PDU session operation method.

[0259] According to one embodiment, when operating a PDU session associated with one terminal in one QUIC connection (e.g., the PDU session operating method of FIG. 4 (a)) or operating a PDU session associated with multiple terminals in one QUIC connection (e.g., the PDU session operating method of FIG. 4 (b)), the base station may generate a new stream ID and re-map it to QFI based on information about a changed PDU session received from an SMF entity. For example, referring to FIG. 15, the SMF entity (509) may change some of the information in the SM policy to information about the number of changed streams, the stream ID of the changed stream, and information about a mapping rule of QFI in accordance with the changed PDU session in operation 1510. Thereafter, in operations 1525 to 1530, the SMF entity (509) may transmit an N2 information message including information on the number of changed streams, the stream ID of the changed streams, and information on the mapping rule of QFI to the base station (503) through the AMF entity (505). Thereafter, the base station (503) may regenerate a stream ID based on the received information on the number of changed streams, the stream ID of the changed stream, and the information on the mapping rule of QFI, and may remap the generated stream ID to the QFI. The base station (503) may transmit the mapping result information of the remapped stream ID and QFI in relation to the changed PDU session to the UPF entity (507) through operations 1550 to 1565. The UPF entity (507) may newly store the mapping result information of the remapped stream ID and QFI received from the base station (503).

[0260] According to one embodiment, when a PDU session associated with one terminal is operated for each of multiple QUIC connections (e.g., the PDU session operation method of (c) of FIG. 4) and a QUIC connection is created in the QUIC layer, the base station may request termination of an existing QUIC connection and creation of a new QUIC connection based on information about a changed PDU session received from an SMF entity. For example, referring to FIG. 15, the SMF entity (509) may change some of the information in the SM policy to information about the number of changed streams, the stream ID of the changed stream, and the mapping rule of QFI according to the changed PDU session in operation 1510. Thereafter, in operations 1525 to 1530, the SMF entity (509) may transmit an N2 information message including information on the number of changed streams, the stream ID of the changed streams, and information on the mapping rule of QFI to the base station (503) through the AMF entity (505). Thereafter, the base station (503) may request termination of an existing QUIC connection and request creation of a new QUIC connection based on the received information on the number of changed streams, the stream ID of the changed stream, and information on the mapping rule of QFI. At this time, there may be multiple QUIC connections for which termination or creation is requested. The base station may remap the QFI and the UPF connection ID and gNB connection ID set associated with the new QUIC connection.The base station (503) can transmit the mapping result information of the new QUIC connection remapped in relation to the changed PDU session, the UPF connection ID and gNB connection ID set associated with it, and the QFI to the UPF entity (507) through operations 1550 to 1565. The UPF entity (507) can newly store the mapping result information received from the base station (503).

[0261] According to one embodiment, when a PDU session associated with one terminal is operated for each of multiple QUIC connections (e.g., the PDU session operation method of (c) of FIG. 4) and the QUIC connection is created within 3GPP using handshake information, the base station may reselect the gNB connection ID according to the changed QFI based on the information about the changed PDU session received from the SMF entity. For example, referring to FIG. 15, the SMF entity (509) may change some of the information in the SM policy according to the changed PDU session in operation 1510 to information about the number of changed streams, the stream ID of the changed stream, and the mapping rule of the QFI. Thereafter, in operations 1525 to 1530, the SMF entity (509) may transmit an N2 information message including information about the number of changed streams, the stream ID of the changed stream, and the mapping rule of the QFI to the base station (503) through the AMF entity (505). The base station (503) can reselect the gNB connection ID according to the changed QFI and include it in the QUIC frame information for the QUIC connection. At this time, if there are multiple QUIC connections, the reselected gNB connection IDs can also be multiple. Thereafter, the base station (503) can map the reselected gNB connection ID and the QFI. The base station (503) can transmit the mapping result information of the reselected gNB connection ID and the QFI, which are remapped in relation to the changed PDU session, to the UPF entity (507) through operations 1550 to 1565.Additionally, the information transmitted to the UPF entity (507) through operations 1550 to 1565 may also include handshake information (e.g., Initial Information, CRYPTO, 0-RTT Information) based on information about the changed PDU session. The UPF entity (507) may newly store the mapping result information and handshake information received from the base station (503). The handshake information based on the information about the changed PDU session may be information required for the handshake procedure for a new QUIC connection, taking into account the possibility of a new QUIC connection occurring.

[0262] FIG. 16 illustrates operations for establishing a PDU session of an SMF (session management function) entity according to one embodiment of the present disclosure. Specifically, FIG. 16 illustrates operations of an SMF entity for establishing a PDU session based on the QUIC protocol.

[0263] An SMF entity may add information to the SM policy necessary to establish a PDU session based on the QUIC protocol prior to operation 1610. In one example, the information that may be added to the SM policy is as follows:

[0264] - Number of streams in a QUIC connection

[0265] - Rules for mapping QFI and stream ID within QER

[0266] - Information about the operation of PDU sessions

[0267] - Instruction information for QUIC connection

[0268] However, the information that can be added to the SM policy is not limited to this, and may include additional information required to operate a PDU session based on the QUIC protocol.

[0269] Information about the number of streams in a QUIC connection can indicate the number of streams in the QUIC connection to be mapped to the QFI of the PDU session. Information about the rule for mapping QFIs and stream IDs in a QER can indicate the rule for using the streams in the QUIC connection for the QFI of the PDU session. In one example, information about the rule for mapping QFIs and stream IDs can indicate information for mapping QFIs and stream IDs one-to-one (1:1) or many-to-one (N:1). For example, information about the rule for mapping QFIs and stream IDs can include information for mapping stream ID 1 to QFI 1 and mapping stream ID 2 to QFIs 2 and 3 for two streams in the QUIC connection. On the other hand, if information about the rule for mapping QFIs and stream IDs indicates information for mapping QFIs and stream IDs many-to-one, data may need to be transmitted by modifying the QUIC header by taking advantage of the characteristic of the QUIC protocol as a user plane protocol. Information about the operation of a PDU session may include information indicating which of several methods of establishing a PDU session will be used. For example, it may indicate a QUIC connection at the UPF entity or a QUIC connection at the base station.

[0270] Instructions for a QUIC connection may include information indicating whether to use a pre-existing QUIC connection or create a new QUIC connection.

[0271] Thereafter, in operation 1610, the SMF entity may send an N4 session establishment request message to the UPF entity. According to one embodiment, the SMF entity may include information in the N4 session establishment request message requesting the UPF entity to set a connection ID (e.g., a UPF connection ID or a gNB connection ID) required when operating a PDU session based on the QUIC protocol.

[0272] Additionally, the N4 session establishment request message may include information about the SM policy updated by the SMF entity. For example, the N4 session establishment request message may include the number of streams in the QUIC connection, rules for mapping QFIs and stream IDs, information about the operation of the PDU session, and instructions about the QUIC connection.

[0273] At operation 1620, the SMF entity may receive an N4 session establishment response message in response to an N4 session establishment request message from the UPF entity.

[0274] According to one embodiment, when a QUIC connection is created in a UPF entity, an N4 session establishment response message may include a UPF connection ID selected by the UPF entity and a gNB connection ID based on the QUIC connection created by the UPF entity. The UPF entity may select a UPF connection ID required when creating a QUIC connection based on an N4 session establishment request message received from an SMF entity. In one example, the UPF entity may select the UPF connection ID in information requesting the establishment of the UPF connection ID included in the N4 session establishment request message. A QUIC connection between a UPF entity and a base station may be created in a QUIC layer of a QUIC protocol in a user plane protocol. In this case, the QUIC connection in the QUIC layer may be created when the UPF connection ID is not transmitted to the base station. Meanwhile, the gNB connection ID of the base station may be used when the QUIC connection between the UPF entity and the base station is created.

[0275] Additionally, according to one embodiment, when a QUIC connection is created at a base station, the N4 session establishment response message may include a UPF connection ID selected by a UPF entity. The UPF entity may select a UPF connection ID required when creating a QUIC connection based on the N4 session establishment request message received from the SMF entity. Since the QUIC connection is not created at the UPF entity, the N4 session establishment response message may not include information about the gNB connection ID of the base station that can be used when creating the QUIC connection.

[0276] In operation 1630, the SMF entity may transmit first N2 information based on the N4 session establishment response message to the base station through the AMF entity. The first N2 information may refer to information related to the N2 session and QUIC connection transmitted by the SMF entity to the base station. In one example, the first N2 information may include information in the SM policy updated by the SMF entity. For example, the first N2 information may include information about the number of streams in the QUIC connection to be created and rules for mapping QFIs and stream IDs.

[0277] In one embodiment, when a QUIC connection is created in a UPF entity, the first N2 information may also include a UPF connection ID and a gNB connection ID. For example, in FIG. 5, the SMF entity may include the UPF connection ID and the gNB connection ID included in the N4 session establishment response message received from the UPF entity in the first N2 information and transmit it to the base station.

[0278] Additionally, according to one embodiment, when a QUIC connection is created at a base station, the first N2 information may also include a UPF connection ID. For example, in FIG. 7, the SMF entity may include the UPF connection ID included in the N4 session establishment response message received from the UPF entity in the first N2 information and transmit it to the base station.

[0279] Additionally, according to one embodiment, the first N2 information may include information required for a handshake to establish a QUIC connection. The information required for the handshake may include at least one of Initial Information, CRYPTO, 0-RTT Information, Handshake Information, and an ACK frame for performing communication with a UPF entity or a base station.

[0280] In operation 1640, the SMF entity may receive second N2 information from the base station through the AMF entity. The second N2 information may refer to information related to the N2 session and QUIC connection that the base station transmits to the SMF entity through the AMF entity. In one example, the second N2 information may include information that the base station maps a stream ID and a QFI. The information that the base station maps a stream ID and a QFI may include a result of the base station mapping the stream ID and the QFI according to a mapping rule. The QFI that the base station maps to the stream ID according to the mapping rule may indicate a QFI that the base station has allowed from a list of QFIs received from the AMF entity. In addition, the second N2 information may include information about a QFI that the base station has rejected from a list of QFIs received from the AMF entity.

[0281] In one embodiment, when a QUIC connection is created at the base station, the second N2 information may also include the gNB connection ID. For example, in FIG. 7, the base station may transmit the gNB connection ID to the SMF entity through the AMF entity by including it in the second N2 information.

[0282] Additionally, according to one embodiment, the second N2 information may include a mapping result between a set of UPF connection IDs and gNB connection IDs corresponding to each QUIC connection and QFI for a plurality of QUIC connections.

[0283] Additionally, according to one embodiment, the second N2 information may include handshake information associated with a QUIC connection generated in a 3GPP network. The handshake information associated with the QUIC connection may include information such as Initial Information, CRYPTO, 1-RTT Information, Handshake Information, and an ACK frame. However, the present invention is not limited thereto.

[0284] At operation 1650, the SMF entity can perform communication using a QUIC connection. The SMF entity can operate a PDU session based on the QUIC protocol using information associated with the QUIC connection received through the UPF entity and the base station. Through this, the SMF entity can perform communication using the QUIC connection.

[0285] According to one embodiment, streams are allocated according to QoS within a single PDU session, so that data transmission and reception can be controlled for each stream. Accordingly, even if data retransmission occurs within one of multiple streams, data transmission and reception can be maintained through streams in which retransmission did not occur within the same PDU session. In other words, data can be transmitted and received while maintaining connectivity without interruption. In addition, when performing communication using the QUIC protocol, it can be easily managed for each data traffic even when using XR, VR, or metaverse applications with many differences in data traffic characteristics.

[0286] FIG. 17 illustrates the structure of a base station according to one embodiment of the present disclosure.

[0287] Referring to FIG. 17, the base station (1700) includes a communication unit (1710), a storage unit (1720), and a control unit (1730).

[0288] The communication unit (1710) performs functions for transmitting and receiving signals via a wireless channel. For example, the communication unit (1710) performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the system. For example, when transmitting data, the communication unit (1710) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the communication unit (1710) restores a reception bit stream by demodulating and decoding the baseband signal. In addition, the communication unit (1710) upconverts a baseband signal into an RF (radio frequency) band signal and transmits it through an antenna, and downconverts an RF band signal received through the antenna into a baseband signal.

[0289] To this end, the communication unit (1210) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), an analog to digital convertor (ADC), etc. In addition, the communication unit (1710) may include a plurality of transmission and reception paths. Furthermore, the communication unit (1710) may include at least one antenna array composed of a plurality of antenna elements. In terms of hardware, the communication unit (1710) may be composed of a digital unit and an analog unit, and the analog unit may be composed of a plurality of sub-units according to operating power, operating frequency, etc.

[0290] The communication unit (1710) can transmit and receive signals. To this end, the communication unit (1710) may include at least one transceiver. For example, the communication unit (1710) may transmit a synchronization signal, a reference signal, system information, messages, control information, or data. In addition, the communication unit (1710) may perform beamforming.

[0291] The communication unit (1710) transmits and receives signals as described above. Accordingly, all or part of the communication unit (1710) may be referred to as a "transmitter," a "receiver," or a "transmitting and receiving unit." Furthermore, in the following description, transmission and reception performed via a wireless channel are used to mean processing performed by the communication unit (1710) as described above.

[0292] The storage unit (1720) stores data such as basic programs, application programs, and setting information for the operation of the base station. The storage unit (1720) may include memory. The storage unit (1720) may be composed of volatile memory, non-volatile memory, or a combination of volatile and non-volatile memory. In addition, the storage unit (1720) provides stored data upon request from the control unit (1730).

[0293] The control unit (1730) controls the overall operations of the base station (1700). For example, the control unit (1730) transmits and receives signals through the communication unit (1710). In addition, the control unit (1730) records and reads data from the storage unit (1720). In addition, the control unit (1730) can perform the functions of the protocol stack required by the communication standard. To this end, the control unit (1730) can include at least one processor.

[0294] The configuration of the base station (1700) illustrated in FIG. 17 is merely an example of a base station, and examples of base stations performing various embodiments of the present disclosure are not limited to the configuration illustrated in FIG. 17. That is, some configurations may be added, deleted, or changed according to various embodiments.

[0295] Although the base station (1700) is described as a single entity in FIG. 17, the present disclosure is not limited thereto. The base station (1700) according to various embodiments of the present disclosure may be implemented to form an access network having not only an integrated deployment but also a distributed deployment. According to one embodiment, the base station may be divided into a central unit (CU) and a digital unit (DU), and the CU may be implemented to perform upper layer functions (e.g., packet data convergence protocol (RRC) PDCP) and the DU may be implemented to perform lower layer functions (e.g., medium access control (MAC), physical (PHY)). The DU of the base station may form beam coverage on a wireless channel.

[0296] FIG. 18 illustrates the structure of a terminal (1800) according to one embodiment of the present disclosure.

[0297] The configuration illustrated in Fig. 18 can be understood as the configuration of a terminal (1800). Terms such as "... unit", ". unit", etc. used hereinafter mean a unit that processes at least one function or operation, and this can be implemented by hardware, software, or a combination of hardware and software.

[0298] Referring to FIG. 18, the terminal (1800) includes a communication unit (1810), a storage unit (1820), and a control unit (1830).

[0299] The communication unit (1810) performs functions for transmitting and receiving signals via a wireless channel. For example, the communication unit (1810) performs a conversion function between a baseband signal and a bit stream according to the physical layer specifications of the system. For example, when transmitting data, the communication unit (1810) generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the communication unit (1810) restores a reception bit stream by demodulating and decoding the baseband signal. In addition, the communication unit (1810) upconverts a baseband signal to an RF band signal and transmits it through an antenna, and downconverts an RF band signal received through the antenna to a baseband signal. For example, the communication unit (1810) may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc.

[0300] In addition, the communication unit (1810) may include a plurality of transmission and reception paths. Furthermore, the communication unit (1810) may include an antenna unit. The communication unit (1810) may include at least one antenna array composed of a plurality of antenna elements. In terms of hardware, the communication unit (1810) may be composed of digital circuits and analog circuits (e.g., radio frequency integrated circuits (RFIC)). Here, the digital circuits and analog circuits may be implemented in a single package. In addition, the communication unit (1810) may include a plurality of RF chains. The communication unit (1810) may perform beamforming. The communication unit (1810) may apply beamforming weights to signals to be transmitted and received in order to impart directionality according to the settings of the control unit (1830). According to one embodiment, the communication unit (1810) may include an RF (radio frequency) block (or RF unit). The RF block may include first RF circuitry associated with the antenna and second RF circuitry associated with baseband processing. The first RF circuitry may be referred to as RF-A (antenna). The second RF circuitry may be referred to as RF-B (baseband).

[0301] Additionally, the communication unit (1810) can transmit and receive signals. To this end, the communication unit (1810) may include at least one transceiver. The communication unit (1810) may receive downlink signals. The downlink signal may include a synchronization signal (SS), a reference signal (RS) (e.g., demodulation (DM)-RS, phase tracking reference signal (PTRS), system information (e.g., MIB, SIB, remaining system information (RMSI), other system information (OSI)), a configuration message, control information, or downlink data, etc.). In addition, the communication unit (1110) may transmit an uplink signal. The uplink signal may include a random access related signal (e.g., a random access preamble (RAP) (or Msg1 (message 1) or Msg3 (message 3)), a reference signal (e.g., a sounding reference signal (SRS), DMRS, PTRS), or a power headroom report (PHR).

[0302] Additionally, the communication unit (1810) may include different communication modules to process signals of different frequency bands. Furthermore, the communication unit (1810) may include multiple communication modules to support multiple different wireless access technologies. For example, different wireless access technologies may include Bluetooth low energy (BLE), Wireless Fidelity (Wi-Fi), WiFi Gigabyte (WiGig), cellular networks (e.g., Long Term Evolution (LTE), new radio (NR), etc.). In addition, different frequency bands may include super high frequency (SHF) (e.g., 2.5 GHz, 5 GHz) bands, millimeter wave (mm wave) (e.g., 38 GHz, 60 GHz, etc.) bands. In addition, the communication unit (1810) may use the same type of wireless access technology on different frequency bands (e.g., unlicensed bands for licensed assisted access (LAA), citizens broadband radio service (CBRS) (e.g., 3.5 GHz)).

[0303] The communication unit (1810) transmits and receives signals as described above. Accordingly, all or part of the communication unit (1810) may be referred to as a "transmitter," a "receiver," or a "transmitting and receiving unit." Furthermore, in the following description, transmission and reception performed via a wireless channel are used to mean processing performed by the communication unit (1810) as described above.

[0304] The storage unit (1820) stores data such as basic programs, application programs, and setting information for the operation of the terminal (1800). The storage unit (1820) may be composed of volatile memory, non-volatile memory, or a combination of volatile and non-volatile memory. In addition, the storage unit (1820) provides stored data upon request from the control unit (1830).

[0305] The control unit (1830) controls the overall operations of the terminal (1800). For example, the control unit (1830) transmits and receives signals through the communication unit (1810). In addition, the control unit (1830) records and reads data in the storage unit (1820). In addition, the control unit (1830) can perform the functions of the protocol stack required by the communication standard. To this end, the control unit (1830) may include at least one processor. The control unit (1830) may include at least one processor or microprocessor, or may be a part of a processor. In addition, a part of the communication unit (1810) and the control unit (1830) may be referred to as a CP. The control unit (1830) may include various modules for performing communication. According to various embodiments, the control unit (1830) may control the terminal to perform operations according to various embodiments.

[0306] FIG. 19 illustrates the structure of a network entity (1900) according to one embodiment of the present disclosure.

[0307] A network entity according to one embodiment of the present disclosure may include a processor (1920) that controls the overall operation of the network entity, a transceiver (1900) including a transmitter and a receiver, and a memory (1910). Of course, the present invention is not limited to the above example, and the network entity may include more or fewer components than those illustrated in FIG. 19.

[0308] According to one embodiment, the transceiver (1900) can transmit and receive signals with at least one of other network entities or terminals. The signals transmitted and received with at least one of the other network entities or terminals can include control information and data.

[0309] According to one embodiment, the processor (1920) may control a network entity to perform any one of the operations described above. Meanwhile, the processor (1920), the memory (1910), and the transceiver (1900) do not necessarily have to be implemented as separate modules, and may of course be implemented as a single component in the form of a single chip. In addition, the processor (1920) and the transceiver (600) may be electrically connected. In addition, the processor (1920) may be an Application Processor (AP), a Communication Processor (CP), a circuit, an application-specific circuit, or at least one processor.

[0310] According to one embodiment, the memory (1910) may store data such as basic programs, application programs, and configuration information for the operation of the network entity. In particular, the memory (1910) provides the stored data upon request of the processor (620). The memory (1910) may be configured as 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, there may be a plurality of memories (1910). In addition, the processor (1920) may perform the above-described embodiments based on a program for performing the above-described embodiments of the present disclosure stored in the memory (1910).

[0311] In the specific embodiments of the present invention described above, components included in the invention are expressed in singular or plural form depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present invention is not limited to singular or plural components. Even components expressed in plural form may be composed of singular elements, or even components expressed in singular form may be composed of plural elements.

[0312] Meanwhile, while the detailed description of the present invention has described specific embodiments, it goes without saying that various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims but also by equivalents of the scope of the claims. In other words, it will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, each of the above embodiments can be combined and operated with each other as needed. For example, parts of the methods proposed in the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above embodiments have been presented based on a 5G, NR system, other modifications based on the technical idea of ​​the above embodiments can be implemented with other systems such as LTE, LTE-A, and LTE-A-Pro systems.

[0313] As described above, a method in which an SMF entity uses a QUIC connection to establish a PDU session in a wireless communication system according to various embodiments disclosed in the present document may include the steps of transmitting an N4 session establishment request message to a UPF entity, receiving an N4 session establishment response message in response to the N4 session establishment request message from the UPF entity, transmitting first N2 information based on the N4 session establishment response message to a base station via an AMF entity, the step of receiving second N2 information from the base station via the AMF entity, and the step of performing communication using the QUIC connection.

[0314] According to various embodiments disclosed in this document, the method may include, when a QUIC connection is created by the UPF entity, an N4 session establishment response message may include a UPF connection ID selected by the UPF entity and a gNB connection ID based on the QUIC connection created by the UPF entity.

[0315] According to various embodiments disclosed in this document, when a QUIC connection is created at the base station, the N4 session establishment response message may include a UPF connection ID selected by the UPF entity, and the second N2 information may include a gNB connection ID based on the QUIC connection created by the base station.

[0316] According to various embodiments disclosed in this document, the first N2 information includes information required for a handshake for creating a QUIC connection, and the information required for the handshake includes at least one of Initial Information, CRYPTO, 0-RTT Information, Handshake Information, and ACK frame for performing communication with a UPF entity or a base station, and the second N2 information may include handshake result information.

[0317] According to various embodiments disclosed in the present document, the method further includes a step of providing an instruction for using the pre-created QUIC connection via an N4 session establishment request message, wherein the first N2 information may include a UPF connection ID and a gNB connection ID corresponding to the pre-created QUIC connection.

[0318] According to various embodiments disclosed in this document, one QUIC connection is assigned to one UE, one QUIC connection includes multiple streams, and the multiple streams may correspond to different stream IDs.

[0319] According to various embodiments disclosed in this document, one QUIC connection is assigned to multiple UEs, one QUIC connection includes multiple streams, the multiple streams correspond to different stream IDs, a first stream among the multiple streams can be assigned to a first UE, and a second stream can be assigned to a second UE.

[0320] According to various embodiments disclosed in this document, multiple QUIC connections are allocated to one UE, and the multiple QUIC connections can correspond to each of multiple streams.

[0321] According to various embodiments disclosed in this document, one QUIC connection is assigned to multiple UEs, one QUIC connection includes multiple streams, the multiple streams correspond to different stream IDs, a first stream among the multiple streams can be assigned to a first UE, and a second stream can be assigned to a second UE.

[0322] According to various embodiments disclosed in this document, multiple QUIC connections are assigned to one UE, and the multiple QUIC connections can correspond to each of multiple streams.

[0323] According to various embodiments disclosed in the present document, the method includes a step of changing an SM policy for a QUIC connection, wherein the step of changing the SM policy includes a step of updating the SM policy by adding at least one of a mapping rule of a stream ID and a QFI, information about the operation of an N4 session, or information indicating a QUIC connection, and an N4 session establishment request message can be transmitted based on the updated SM policy.

[0324] According to various embodiments disclosed in the present document, the method further includes the step of transmitting, to the base station via the AMF entity, third N2 information including information on the number of changed streams and at least one of a mapping rule between the changed stream ID and QFI, and the step of receiving, from the base station via the AMF entity, fourth N2 information, wherein the third N2 information may include at least one of information on the number of changed streams and a mapping rule between the changed stream ID and QFI.

[0325] According to various embodiments disclosed in the present document, the method may further include a step of storing at least one of a mapping rule of a stream ID and a QFI, a UPF connection ID, and a gNB connection ID based on the second N2 information.

[0326] As described above, a method performed by a user plane function (UPF) entity in a wireless communication system according to various embodiments disclosed in the present document includes the steps of receiving an N4 session establishment request message from a session management function (SMF) entity, and transmitting an N4 session establishment response message to the SMF entity in response to the N4 session establishment request message, wherein the N4 session establishment request message is based on an SM policy updated by the SMF entity for a QUIC connection, and the N4 session establishment response message may include a UPF connection ID.

[0327] According to various embodiments disclosed in this document, a QUIC connection may be terminated by sending an N4 session release response message including connection close information for termination of the QUIC connection to the SMF entity when termination of the QUIC connection is indicated at the QUIC layer or when an N4 session release request message is received from an SMF entity, or by deleting a gNB connection ID and a UPF connection ID corresponding to the QUIC connection.

[0328] As described above, in a wireless communication system according to various embodiments disclosed in the present document, an SMF entity using a QUIC connection for establishing a PDU session includes a transceiver and a controller coupled with the transceiver, wherein the controller transmits an N4 session establishment request message to a UPF entity, receives an N4 session establishment response message in response to the N4 session establishment request message from the UPF entity, transmits first N2 information based on the N4 session establishment response message to a base station through an AMF entity, receives second N2 information from the base station through the AMF entity, and is configured to perform communication using the QUIC connection, wherein the first N2 information may include at least one of information on the number of streams to be included in the QUIC connection, a mapping rule between a stream ID and a QFI, and a UPF connection ID.

[0329] According to various embodiments disclosed in this document, when a QUIC connection is created by a UPF entity, the N4 session establishment response message may include a UPF connection ID selected by the UPF entity and a gNB connection ID based on the QUIC connection created by the UPF entity.

[0330] According to various embodiments disclosed in this document, when a QUIC connection is created at a base station, the N4 session establishment response message may include a UPF connection ID selected by a UPF entity, and the second N2 information may include a gNB connection ID based on the QUIC connection created by the base station.

[0331] According to various embodiments disclosed in this document, the first N2 information includes information required for a handshake for creating a QUIC connection, and the information required for the handshake includes at least one of Initial Information, CRYPTO, 0-RTT Information, Handshake Information, and ACK frame for performing communication with a UPF entity or a base station, and the second N2 information may include handshake result information.

[0332] According to various embodiments disclosed in this document, the controller is configured to provide an instruction for using a pre-created QUIC connection via an N4 session establishment request message, and the first N2 information may include a UPF connection ID and a gNB connection ID corresponding to the pre-created QUIC connection.

[0333] According to various embodiments disclosed in this document, one QUIC connection is assigned to one UE, one QUIC connection includes multiple streams, and the multiple streams may correspond to different stream IDs.

[0334] According to various embodiments disclosed in this document, one QUIC connection is assigned to multiple UEs, one QUIC connection includes multiple streams, the multiple streams correspond to different stream IDs, a first stream among the multiple streams can be assigned to a first UE, and a second stream can be assigned to a second UE.

[0335] According to various embodiments disclosed in this document, multiple QUIC connections are allocated to one UE, and the multiple QUIC connections can correspond to each of multiple streams.

[0336] According to various embodiments disclosed in this document, the controller is configured to change the SM policy for a QUIC connection by updating the SM policy by adding at least one of a mapping rule of a stream ID and a QFI, information on the operation of an N4 session, or information indicating a QUIC connection, and an N4 session establishment request message can be transmitted based on the updated SM policy.

[0337] According to various embodiments disclosed in the present document, the controller is further configured to transmit third N2 information including at least one of information on the number of changed streams and a mapping rule between the changed stream ID and QFI to the base station via the AMF entity, and to receive fourth N2 information from the base station via the AMF entity, wherein the third N2 information may include at least one of information on the number of changed streams and a mapping rule between the changed stream ID and QFI.

[0338] According to various embodiments disclosed in this document, the controller may be further configured to store at least one of a mapping rule of stream ID and QFI, a UPF connection ID, and a gNB connection ID based on the second N2 information.

[0339] As described above, in a wireless communication system according to various embodiments disclosed in the present document, a UPF entity includes a transceiver and a controller coupled with the transceiver, and the controller is configured to receive an N4 session establishment request message from an SMF entity and to transmit an N4 session establishment response message to the SMF entity in response to the N4 session establishment request message, wherein the N4 session establishment request message is based on an SM policy updated by the SMF entity for a QUIC connection, and the N4 session establishment response message may include a UPF connection ID.

[0340] According to various embodiments disclosed in this document, a QUIC connection may be terminated by sending an N4 session release response message including connection close information for termination of the QUIC connection to the SMF entity when termination of the QUIC connection is indicated at the QUIC layer or an N4 session release request message is received from an SMF entity, or by deleting a gNB connection ID and a UPF connection ID corresponding to the QUIC connection.

Claims

1. In a wireless communication system, a method in which an SMF (session management function) entity uses a QUIC (quick user datagram protocol internet connection) connection to establish a PDU session, A step of sending an N4 session establishment request message to a UPF (user plane function) entity; A step of receiving an N4 session establishment response message in response to the N4 session establishment request message from the UPF entity; A step of transmitting first N2 information based on the N4 session establishment response message to a base station through an AMF (access and mobility management function) entity; A step of receiving second N2 information from the base station through the AMF entity; and Comprising a step of performing communication using the above QUIC connection, A method, wherein the first N2 information includes at least one of information on the number of streams to be included in a QUIC connection, a mapping rule between a stream ID (identifier) ​​and a quality of service flow identifier (QFI), and a UPF connection ID.

2. In claim 1, the method comprises: If the above QUIC connection is created from the above UPF entity, A method, wherein the N4 session establishment response message includes the UPF connection ID selected by the UPF entity and the gNB connection ID based on the QUIC connection created by the UPF entity.

3. In claim 1, When the above QUIC connection is created at the above base station, The above N4 session establishment response message includes the UPF connection ID selected by the UPF entity, A method, wherein the second N2 information includes a gNB connection ID based on a QUIC connection generated by the base station.

4. In claim 1, The above first N2 information includes information required for a handshake for creating a QUIC connection, The information required for the above handshake includes at least one of Initial Information, CRYPTO, 0-RTT Information, Handshake Information, and ACK frame for performing communication with the UPF entity or the base station. A method, wherein the above second N2 information includes handshake result information.

5. In claim 1, the method comprises: Further comprising a step of providing information indicating the use of a QUIC connection created through the above N4 session establishment request message, A method wherein the first N2 information includes a UPF connection ID and a gNB connection ID corresponding to the generated QUIC connection.

6. In claim 1, One QUIC connection is assigned to one UE. The above one QUIC connection contains multiple streams, A method wherein the plurality of streams correspond to different stream IDs.

7. In claim 1, A single QUIC connection is assigned to multiple UEs. The above one QUIC connection contains multiple streams, The above multiple streams correspond to different stream IDs, A method, wherein a first stream among the plurality of streams is allocated to a first UE, and a second stream is allocated to a second UE.

8. In a SMF (session management function) entity that uses a QUIC (quick user datagram protocol internet connection) connection to establish a PDU session in a wireless communication system, transceiver; and A controller coupled with the above transmitter and receiver is included, The above controller, Send an N4 session establishment request message to the UPF (user plane function) entity, From the above UPF entity, an N4 session establishment response message is received in response to the above N4 session establishment request message, Transmitting the first N2 information based on the N4 session establishment response message to the base station through the AMF (access and mobility management function) entity, Receives the second N2 information from the base station through the above AMF entity, It is set to perform communication using the above QUIC connection, An SMF entity wherein the above first N2 information includes at least one of information on the number of streams to be included in a QUIC connection, a mapping rule between a stream ID (identifier) ​​and a quality of service flow identifier (QFI), and a UPF connection ID.

9. In claim 8, If the above QUIC connection is created from the above UPF entity, An SMF entity, wherein the N4 session establishment response message includes the UPF connection ID selected by the UPF entity and the gNB connection ID based on the QUIC connection created by the UPF entity.

10. In claim 8, When the above QUIC connection is created at the above base station, The above N4 session establishment response message includes the UPF connection ID selected by the UPF entity, An SMF entity wherein the second N2 information includes a gNB connection ID based on a QUIC connection generated by the base station.

11. In claim 8, The above first N2 information includes information required for a handshake for creating a QUIC connection, The information required for the above handshake includes at least one of Initial Information, CRYPTO, 0-RTT Information, Handshake Information, and ACK frame for performing communication with the UPF entity or the base station. The above second N2 information is an SMF entity that includes handshake result information.

12. In claim 2, the controller, It is set to provide information indicating the use of the QUIC connection created through the above N4 session establishment request message, The above first N2 information is an SMF entity including a UPF connection ID and a gNB connection ID corresponding to the above-mentioned parasitic QUIC connection.

13. In claim 8, One QUIC connection is assigned to one UE. The above one QUIC connection contains multiple streams, An SMF entity in which the above multiple streams correspond to different stream IDs.

14. In claim 8, A single QUIC connection is assigned to multiple UEs. The above one QUIC connection contains multiple streams, The above multiple streams correspond to different stream IDs, An SMF entity, wherein a first stream among the plurality of streams is allocated to a first UE, and a second stream is allocated to a second UE.

15. In a wireless communication system, for a UPF (user plane function) entity, transceiver; and A controller coupled with the above transmitter and receiver is included, The above controller, Receive an N4 session establishment request message from the SMF (session management function) entity, It is set to send an N4 session establishment response message to the above SMF entity in response to the above N4 session establishment request message, The above N4 session establishment request message is based on the SM policy updated by the SMF entity for QUIC connection. The above N4 session establishment response message is a UPF entity that includes a UPF connection ID.

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