Method and apparatus for performing metric delivery to support l4s

Abstract

The present disclosure relates to a metric delivery method and apparatus for L4S support. The method includes a step of determining, by a first entity of a first device, whether to deliver currently measured metric information to a second entity on the basis of a change in ECN mark probability corresponding to change information of a congestion control metric, and transmitting a packet to the second device according to the ECN mark probability determined on the basis of the delivered information.

Description

Method and device for performing indicator transmission to support L4S

[0001] The present disclosure relates to terminals and network entities in a communication system. More specifically, the present disclosure relates to a method and apparatus for performing L4S (Low Latency, Low Loss, and Scalable Throughput) operations in a communication system.

[0002] Looking back at the evolution of wireless communication through successive generations, technologies have been developed primarily for human-oriented services, such as voice, multimedia, and data. Following the commercialization of 5G (5th-generation) communication systems, connected devices, which have been increasing explosively, 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 expected to evolve into various form factors, such as augmented reality glasses, virtual reality headsets, and holographic devices. In the 6G (6th-generation) era, efforts are underway to develop improved 6G communication systems to connect hundreds of billions of devices and objects to provide diverse services. For this reason, 6G communication systems are referred to as "Beyond 5G" systems.

[0003] In the 6G communication system predicted to be realized around 2030, the maximum transmission speed is tera (i.e., 1,000 gigabit) bps, and the wireless latency is 100 microseconds (μsec). In other words, compared to the 5G communication system, the transmission speed in the 6G communication system is 50 times faster, and the wireless latency is reduced to one-tenth.

[0004] To achieve such high data transmission speeds and ultra-low latency, 6G communication systems are being considered for implementation in the terahertz band (e.g., the 95 GHz to 3 terahertz (3 THz) band). In the terahertz band, due to more severe path loss and atmospheric absorption compared to the millimeter wave (mmWave) band introduced in 5G, the importance of technology capable of guaranteeing signal reach, or coverage, is expected to increase. As key technologies to ensure coverage, new waveforms, beamforming, and multi-antenna transmission technologies such as massive multiple-input and multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas, which offer superior coverage compared to RF (radio frequency) devices, antennas, and OFDM (orthogonal frequency division multiplexing), must be developed. In addition, new technologies such as metamaterial-based lenses and antennas, high-dimensional spatial multiplexing technology using OAM (orbital angular momentum), and RIS (reconfigurable intelligent surface) are being discussed to improve coverage of terahertz band signals.

[0005] In addition, to improve frequency efficiency and system network, development is underway in 6G communication systems for full duplex technology, in which uplink and downlink simultaneously utilize the same frequency resources at the same time; network technology that integrates satellites and HAPS (high-altitude platform stations); network structure innovation technology that supports mobile base stations and enables network operation optimization and automation; dynamic spectrum sharing technology through collision avoidance based on spectrum usage prediction; AI-based communication technology that utilizes AI 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 of complexity exceeding the limits of terminal computing capabilities by utilizing ultra-high performance communication and computing resources (mobile edge computing (MEC), cloud, etc.). In addition, attempts are continuing to further strengthen connectivity between devices, further optimize networks, promote the softwareization of network entities, and increase the openness of wireless communication 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 utilization of data, and the development of technologies regarding privacy maintenance methods.

[0006] Due to the research and development of such 6G communication systems, it is expected that a new dimension of hyper-connected experience will become possible through the hyper-connectivity of 6G communication systems, which encompasses not only connections between objects but also connections between people and objects. Specifically, it is projected that 6G communication systems will enable the provision of 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 will be provided through 6G communication systems by enhancing security and reliability, leading to applications in various fields including industry, healthcare, automotive, and home appliances.

[0007] L4S operation was introduced to provide low-latency services. If the Congestion Metric Delivery interval is shortened to increase the accuracy of congestion detection in L4S operation, signaling increases. Conversely, if the Congestion Metric Delivery interval is lengthened to reduce terminal current consumption, the accuracy of congestion detection decreases.

[0008] To solve these problems and reduce the battery consumption of the terminal, the present disclosure proposes a new algorithm for the delivery of indicator information (or Congestion Metric Delivery).

[0009] The technical problems to be solved in the embodiments of the present disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below.

[0010] According to an embodiment of the present invention for solving the above-mentioned problems, a method performed by a first device comprising a first entity and a second entity in a mobile communication system comprises: a step of obtaining change information of a metric for congestion control in the first entity of the first device; a step of determining whether to transmit currently measured first metric information (d_new) to the second entity of the first device based on change information of an Explicit Congestion Notification (ECN) marking probability (P) corresponding to the change information of the metric in the first entity of the first device; a step of determining a value of an ECN marking probability corresponding to the first metric information in the second entity of the first device when the first metric information is transmitted to the second entity of the first device; and a step of transmitting a packet marked with an ECN to the second device based on the determined ECN marking probability value.

[0011] According to another embodiment of the present invention, in a mobile communication system, a first device comprises a first entity and a second entity, wherein the first entity of the first device obtains information on a change in a metric for congestion control, and determines whether to transmit a currently measured first metric information (d_new) to the second entity of the first device based on information on a change in an Explicit Congestion Notification (ECN) marking probability (P) corresponding to the information on the change in the metric, and if the first metric information is transmitted to the second entity of the first device, the second entity of the first device determines a value of an ECN marking probability corresponding to the first metric information, and transmits a packet marked with an ECN to the second device based on the determined ECN marking probability value.

[0012] According to one embodiment of the present disclosure, a low-latency service can be effectively provided in a wireless communication system.

[0013] More specifically, signaling between the terminal's Communication Processor (CP) and Application Processor (AP) can be reduced, thereby reducing the load. Additionally, the terminal's battery consumption can be reduced by decreasing the terminal's current consumption.

[0014] The effects obtainable in the present disclosure are not limited to those mentioned in the various embodiments, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure pertains from the description below.

[0015] In order to more clearly explain the technical methods of the embodiments proposed in this disclosure, the drawings of the embodiments are briefly introduced. The following drawings are for reference only to the embodiments of this disclosure and are not intended to limit this disclosure.

[0016] FIG. 1 is a drawing illustrating a next-generation mobile communication system to which the present disclosure can be applied.

[0017] FIG. 2 is a diagram illustrating the protocol structure of a communication system to which the present disclosure can be applied.

[0018] FIG. 3a is a diagram illustrating the concept of L4S (Low Latency, Low Loss, and Scalable throughput) communication according to one embodiment of the present disclosure.

[0019] FIG. 3b is a diagram illustrating the concept of L4S (Low Latency, Low Loss, and Scalable throughput) communication according to one embodiment of the present disclosure.

[0020] FIG. 4 is a diagram illustrating the specific operation of L4S (Low Latency, Low Loss, and Scalable throughput) communication according to one embodiment of the present disclosure.

[0021] FIG. 5a is a diagram illustrating the operation of a terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or a base station determination L4S (BS-driven L4S) according to one embodiment of the present disclosure.

[0022] FIG. 5b is a diagram illustrating the operation of a terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or a base station determination L4S (BS-driven L4S) according to one embodiment of the present disclosure.

[0023] FIG. 6 is a flowchart illustrating the overall sequence of terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0024] FIG. 7 is a diagram illustrating a first embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0025] FIG. 8 is a diagram illustrating a second embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0026] FIG. 9a is a diagram illustrating a third embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0027] FIG. 9b is a drawing for illustrating a third embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0028] FIG. 10 is a drawing for explaining the initial connection process of a terminal according to one embodiment of the present disclosure.

[0029] FIG. 11a is a drawing for explaining a 4-1 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0030] FIG. 11b is a drawing for explaining a 4-1 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0031] FIG. 11c is a drawing for explaining a 4-1 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0032] FIG. 12a is a drawing for explaining a 4-2 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0033] FIG. 12b is a drawing for explaining a 4-2 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0034] FIG. 12c is a drawing for explaining a 4-2 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0035] FIG. 13a is a drawing for explaining the effects of the invention according to one embodiment of the present disclosure.

[0036] FIG. 13b is a drawing for explaining the effects of the invention according to one embodiment of the present disclosure.

[0037] FIG. 14 is a drawing illustrating the internal structure of a terminal according to one embodiment of the present disclosure.

[0038] FIG. 15 is a drawing illustrating the internal structure of a base station according to one embodiment of the present disclosure.

[0039] Embodiments of the present disclosure will be described in detail below with reference to the attached drawings.

[0040] In describing the embodiments, descriptions of technical details that are well known in the technical field to which this disclosure belongs and are not directly related to this disclosure are omitted.

[0041] This is intended to convey the gist of the present disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0042] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the dimensions of each component do not entirely reflect their actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference number.

[0043] The advantages and features of the present disclosure and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings.

[0044] However, the present disclosure is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to complete the configuration of the present disclosure and to fully inform those skilled in the art of the scope of the invention, and the present disclosure is defined only by the scope of the claims. Throughout the specification, like reference numerals refer to like components.

[0045] At this time, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory oriented toward the computer or other programmable data processing equipment to be implemented in a specific manner, the instructions stored in such computer-available or computer-readable memory can also produce a manufactured item containing means of instruction to perform the functions described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that perform a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer can also provide steps for executing the functions described in the flowchart block(s).

[0046] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specified logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For instance, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may be executed in reverse order according to their corresponding functions.

[0047] In this embodiment, the term "part" refers to a software or hardware component, such as an FPGA or ASIC, and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium and may be configured to run one or more processors. Thus, as an example, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and indicators. The functions provided within the components and "parts" may be combined into a smaller number of components and "parts" or further separated into additional components and "parts." In addition, the components and '~parts' may be implemented to play one or more CPUs within the device or secure multimedia card.

[0048] For the convenience of the following description, some terms and names defined in 3GPP (3rd generation partnership project) standards (specifications for 5G, NR, LTE, or similar systems) may be used. Additionally, terms and names newly defined in next-generation communication systems to which this disclosure applies (e.g., 6G, Beyond 5G systems) or used in existing communication systems may be used. The use of such terms is not limited to the terms and names of this disclosure and may be applied equally to systems conforming to other standards, and may be modified in other forms without departing from the technical spirit of this disclosure. Embodiments of this disclosure can be easily modified and applied to other communication systems as well.

[0049] In addition, it will be understood that singular expressions such as "one" and "the above" in one embodiment of the present disclosure, unless otherwise explicitly indicated, include plural expressions.

[0050] Additionally, in one embodiment of the present disclosure, terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. Such terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, the first component may be named the second component, and similarly, the second component may be named the first component.

[0051] Additionally, in one embodiment of the present disclosure, the term "and / or" includes a combination of a plurality of related described items or any one of a plurality of related described items.

[0052] Furthermore, the terms used in the embodiments of the present disclosure are used merely to describe specific embodiments and are not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0053] Additionally, the terms “associated with” and “associated therewith” and their derivatives used in one embodiment of the present disclosure may mean things such as include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicated with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, etc.

[0054] Additionally, in this disclosure, expressions such as "greater than" or "less than" have been used to determine whether a specific condition is satisfied or fulfilled; however, this is merely for the purpose of expressing an example and does not exclude descriptions of "greater than" or "less than." Conditions described as "greater than" may be replaced with "greater than," conditions described as "less than" may be replaced with "less than," and conditions described as "greater than and less than" may be replaced with "greater than and less than."

[0055] Additionally, in this disclosure, embodiments are described using terms used in some communication standards (e.g., LTE (long term evolution), NR (new radio) as defined by 3GPP (3rd generation partnership project)), but this is merely for illustrative purposes. The embodiments of this disclosure can be easily modified and applied to other communication systems.

[0056] Prior to a detailed description of the present disclosure, examples of possible meanings for some terms used in this specification are provided. However, it should be noted that the interpretations provided below are not limited to these examples.

[0057] In the present disclosure, a terminal (or communication terminal) is a subject that communicates with a base station or another terminal and may be referred to as a node, UE (user equipment), NG UE (next generation UE), MS (mobile station), device, or terminal. Additionally, the terminal may include at least one of a smartphone, tablet PC, mobile phone, video phone, e-book reader, desktop PC, laptop PC, netbook computer, PDA, PMP (portable multimedia player), MP3 player, medical device, camera, or wearable device. Additionally, the terminal may include at least one of a television, DVD (digital video disk) player, audio, refrigerator, air conditioner, vacuum cleaner, oven, microwave, washing machine, air purifier, set-top box, home automation control panel, security control panel, media box, game console, electronic dictionary, electronic key, camcorder, or electronic photo frame.In addition, the terminal may include at least one of various medical devices (e.g., various portable medical measuring devices (blood glucose meter, heart rate monitor, blood pressure monitor, or body temperature monitor, etc.), MRA (magnetic resonance angiography), MRI (magnetic resonance imaging), CT (computed tomography), imaging device, or ultrasound device, etc.), navigation device, satellite navigation system (GNSS (global navigation satellite system)), EDR (event data recorder), FDR (flight data recorder), automotive infotainment device, marine electronic equipment (e.g., marine navigation device, gyrocompass, etc.), avionics, security device, vehicle head unit, industrial or household robot, drone, ATM of a financial institution, POS (point of sales) of a store, or Internet of Things device (e.g., light bulb, various sensor, sprinkler device, fire alarm, thermostat, street light, toaster, exercise equipment, hot water tank, heater, boiler, etc.). In addition, the terminal may include various types of multimedia systems capable of performing communication functions. Meanwhile, the present disclosure is not limited to what has been described above, and the terminal may be referred to by terms having the same or similar meaning.

[0058] In addition, in the present disclosure, the base station is an entity that communicates with a terminal and performs resource allocation for the terminal, and may take various forms and may be referred to as a BS (base station), NodeB (NB), NG RAN (next generation radio Access network), AP (Access point), TRP (transmission reception point), radio access unit, base station controller, or node on a network. Alternatively, depending on the separation of functions, it may be referred to as a CU (centralized unit) or a DU (distributed unit). Meanwhile, the present disclosure is not limited thereto, and the base station may be referred to by a term having the same or similar meaning.

[0059] Additionally, in this disclosure, an RRC (radio resource control) message may be referred to as high-level information, high-level message, high-level signal, high-level signaling, high-layer signaling, or high-level signaling, and this disclosure is not limited thereto, but may be referred to by terms having the same or similar meaning.

[0060] Additionally, in the present disclosure, data may be referred to as user data, UP (user plane) data, or application data, or may be referred to by a term having the same or similar meaning as a signal transmitted or received through a DRB (data radio bearer).

[0061] Additionally, in the present disclosure, the direction of data transmitted from a terminal may be referred to as an uplink, and the direction of data transmitted to a terminal may be referred to as a downlink. Accordingly, in the case of uplink transmission, the transmitter may refer to a terminal, and the receiver may refer to a specific network entity of a base station or communication system. Alternatively, in the case of downlink transmission, the transmitter may refer to a specific network entity of a base station or communication system, and the receiver may refer to a terminal.

[0062] FIG. 1 is a drawing illustrating a next-generation mobile communication system to which the present disclosure can be applied.

[0063] Referring to FIG. 1, the illustrated RAN (radio access network) nodes (1-100, 1-200) may refer to LTE eNB (evolved Node B, eNodeB), NR gNB (next generation Node B, gNodeB), a base station of a next-generation mobile communication system, or a network node performing the same or similar functions connected to a core network (CN) such as EPC (Evolved Packet Core) or 5GC (5G Core Network). Meanwhile, the functions of the RAN nodes (1-100, 1-200) may be separated into a CU (centralized unit) and a DU (distributed unit), and the CU may be further separated into a CU-CP (control plane) and a CU-UP (user plane).

[0064] In the present disclosure, a single RAN node may be composed of one or more CU-CPs, one or more CU-UPs, and one or more DUs. Additionally, a single RAN node may be composed of CU-CPs, CU-UPs, and DUs. For example, a single RAN node may be composed of a CU and a DU in which CU-CPs and CU-UPs are implemented together. Alternatively, a single RAN node may be configured in the form of an integrated base station in which CU-CPs, CU-UPs, and DUs are implemented together. Meanwhile, the configuration of a RAN node as described above is merely an example, and the present disclosure is not limited thereto. A single RAN node may be configured in any other combination other than the example described above.

[0065] In the present disclosure, the CU and DU can each support the functions of the base station separately. For example, the CU can support the functions of the RRC (radio resource control) layer or the PDCP (packet data convergence protocol) layer, and the DU can support the functions of the RLC (radio link control) layer, the MAC (medium access control) layer, the PHY (physical) layer, or the RF (radio frequency) layer. In addition, the CU and DU can be connected to each other through interfaces between internal base station functions, such as the W1 interface or the F1 interface. Meanwhile, specific details regarding the functions of each layer supported by the CU and DU will be described later in FIG. 2.

[0066] In the present disclosure, the CU may be divided into CU-CP and CU-UP. In this case, for example, CU-CP may support the functions of the RRC layer or the PDCP (for RRC) layer, and CU-UP may support the functions of the PDCH (for user data transmission) layer. CU-CP and CU-UP may be connected through an interface between internal base station functions, such as an E1 interface.

[0067] Additionally, in the present disclosure, RAN nodes or base stations may be implemented in an integral structure or a separated structure, and connections may be possible between integral structure base stations, between separated base stations, and between integral structure base stations and separated structure base stations. RAN nodes may be connected through inter-base station interfaces such as X2 interfaces or Xn interfaces. Additionally, RAN nodes and core networks may be connected through base station-core network interfaces such as S1 interfaces or NG interfaces.

[0068] Additionally, in the present disclosure, the core network may be configured to include various network entities (e.g., network entities performing specific functions such as UPF (user plane function), SMF (session management function), AMF (access and mobility function), NEF (network exposure function), or AF (application function).

[0069] UPF is a network function (NF) responsible for the user plane in the core network. UPF can perform the function of mapping packets of an IP (internet protocol) flow to a specific QoS flow belonging to a specific PDU (protocol data unit) session based on information received from one of the control plane NFs (e.g., SMF) (e.g., at least one of PDR (packet detection rule), FAR (forwarding action rule), QER (quality of service enforcement rule), or URR (usage reporting rule).

[0070] The SMF is one of the network functions (NFs) responsible for the control plane in the core network. The SMF can transmit information necessary to guarantee QoS (quality of service) (e.g., at least one of QFI (QoS flow indicator), QoS profile, PDR, FAR, QER, or URR) to the UPF and the base station. Additionally, during the PDU session establishment procedure, the SMF can determine a UP security policy regarding whether to enable UP confidentiality or UP integrity for all DRBs belonging to the PDU session, and transmit this to the base station via the AMF.

[0071] Meanwhile, the communication system described above is merely an example of a communication system to which the present disclosure may be applied, and the present disclosure is not limited thereto. That is, the embodiments proposed in the present disclosure may be applied and implemented in various communication systems.

[0072] FIG. 2 is a diagram illustrating a protocol of a communication system to which the present disclosure can be applied.

[0073] Referring to FIG. 2, the protocol structure of the communication system can be composed of SDAP (service data adaptation protocol) (2-01, 2-45), PDCP (2-05, 2-40), RLC (2-10, 2-35), MAC (2-14-, 2-30), and PHY (2-20, 2-25) at the terminal and base station, respectively.

[0074] The main functions of SDAP (2-01, 2-45) may include some of the following functions.

[0075] - User data transfer function (transfer of user plane data)

[0076] - Mapping function between a QoS flow and a DRB for both DL and UL for uplink and downlink

[0077] - Marking QoS flow ID for uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0078] - Function to map reflective QoS flow to data bearers for uplink SDAP PDUs (reflective QoS flow to DRB Mapping for the UL SDAP PDUs).

[0079] For the SDAP layer (or SDAP layer device), the terminal may receive a radio resource control (RRC) message indicating whether to use the header of the SDAP layer device or to use the functions of the SDAP layer device for each PDCP layer, for each bearer, or for each logical channel. If the SDAP header is configured, the terminal may be instructed to update or reset the mapping information for the uplink and downlink QoS flows and data bearers using the 1-bit indicator for Non-Access Stratum (NAS) Quality of Service (QoS) reflection (NAS reflective QoS) and the 1-bit indicator for Access Stratum (AS) QoS reflection (AS reflective QoS) of the SDAP header. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used for data processing priority, scheduling information, etc., to support seamless service.

[0080] The main functions of PDCP (2-05, 2-40) may include some of the following functions.

[0081] - Header compression and decompression features (ROHC only)

[0082] - User data transfer function (Transfer of user data)

[0083] - Sequential delivery function (In-sequence Delivery of upper layer PDUs)

[0084] - Out-of-sequence Delivery of upper layer PDUs

[0085] - Reordering function (PDCP PDU reordering for reception)

[0086] - Duplicate detection function (Duplicate detection of lower layer SDUs)

[0087] - Retransmission function (Retransmission of PDCP SDUs)

[0088] - Encryption and decryption functions (Ciphering and deciphering)

[0089] - Timer-based SDU discard in uplink.

[0090] In the above description, the reordering function of the PDCP layer (or PDCH layer device) may refer to a function that reorders PDCP PDUs received from a lower layer in order based on the PDCP SN (sequence number). The reordering function of the PDCP layer may include a function that transmits data to an upper layer in the reordered order. Alternatively, the reordering function of the PDCP layer may include a function that transmits data immediately without considering the order. Furthermore, the reordering function of the PDCP layer may include a function that records lost PDCP PDUs by reordering them, a function that reports the status of lost PDCP PDUs to the transmitting side, and a function that requests retransmission of lost PDCP PDUs.

[0091] The main functions of RLC (2-10, 2-35) may include some of the following functions.

[0092] - Data transfer function (Transfer of upper layer PDUs)

[0093] - Sequential delivery function (In-sequence Delivery of upper layer PDUs)

[0094] - Out-of-sequence Delivery of upper layer PDUs

[0095] - ARQ function (Error Correction through ARQ)

[0096] - Concatenation, segmentation, and reassembly functions (Concatenation, segmentation and reassembly of RLC SDUs)

[0097] - Re-segmentation function (Re-segmentation of RLC data PDUs)

[0098] - Reordering function (Reordering of RLC data PDUs)

[0099] - Duplicate detection

[0100] - Error detection function (Protocol error detection)

[0101] - RLC SDU discard function

[0102] - RLC re-establishment function

[0103] In the foregoing, the in-sequence delivery function of the RLC layer (or RLC layer device) may refer to the function of delivering RLC SDUs received from a lower layer to an upper layer in sequence. If a single RLC SDU is originally received divided into multiple RLC SDUs, the in-sequence delivery function of the RLC layer may include the function of reassembling and delivering them.

[0104] The in-sequence delivery function of the RLC layer may include a function to reorder received RLC PDUs based on an RLC SN (sequence number) or a PDCP SN (sequence number). Additionally, the in-sequence delivery function of the RLC layer may include a function to record lost RLC PDUs by reordering them. Furthermore, the in-sequence delivery function of the RLC layer may include a function to report the status of lost RLC PDUs to the transmitting side and a function to request retransmission of lost RLC PDUs.

[0105] The in-sequence delivery function of the RLC layer may include a function that, in the event of a lost RLC SDU, delivers only the RLC SDUs prior to the lost RLC SDU in order to the upper layer.

[0106] The in-sequence delivery function of the RLC layer may include the function of delivering all RLC SDUs received before the timer started to the upper layer in order, even if there are lost RLC SDUs, if a predetermined timer has expired.

[0107] The in-sequence delivery function of the RLC layer may include the function of delivering all RLC SDUs received up to the present to the upper layer in order when a predetermined timer expires, even if there are lost RLC SDUs.

[0108] The RLC layer can process RLC PDUs in the order they are received (Out-of-sequence Delivery) regardless of the sequence number and forward them to the NR PDCP layer.

[0109] When the RLC layer receives a segment, it can receive segments stored in the buffer or to be received later, reconstruct them into a single complete RLC PDU, and then pass it to the PDCP layer.

[0110] The RLC layer may not include a concatenation function. Alternatively, the concatenation function may be performed in the MAC layer, or the concatenation function may be replaced by the multiplexing function of the MAC layer.

[0111] In the above description, the out-of-sequence delivery function of the RLC layer may refer to the function of delivering RLC SDUs received from a lower layer directly to an upper layer regardless of order. The out-of-sequence delivery function of the RLC layer may include the function of reassembling and delivering RLC SDUs when a single RLC SDU is received divided into multiple RLC SDUs. The out-of-sequence delivery function of the RLC layer may include the function of storing the RLC SN or PDCP SN of the received RLC PDUs, sorting the order, and recording lost RLC PDUs.

[0112] MAC (2-15, 2-30) can be connected to multiple NR RLC layers configured in a terminal, and the main functions of the NR MAC may include some of the following functions.

[0113] - Mapping function (Mapping between logical channels and transport channels)

[0114] - Multiplexing and demultiplexing functions (Multiplexing / demultiplexing of MAC SDUs)

[0115] - Scheduling information reporting function

[0116] - HARQ function (Error correction through HARQ)

[0117] - Priority handling between logical channels of one UE

[0118] - Priority handling between UEs by means of dynamic scheduling

[0119] - MBMS service identification function

[0120] - Transport format selection function

[0121] - Padding

[0122] The PHY layer (2-20, 2-25) can perform the operation of channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting them over a wireless channel, or demodulating OFDM symbols received over a wireless channel and channel decoding them to transmit them to the upper layer.

[0123] Meanwhile, the functions or names of each layer of the protocol structure described with reference to Fig. 2 may be changed.

[0124] FIGS. 3a and 3b are drawings for explaining the concept of L4S (Low Latency, Low Loss, and Scalable throughput) communication according to one embodiment of the present disclosure.

[0125] Recently, the demand for immersive or conversational applications such as Augmented Reality (AR), Extended Reality (XR), video calls, cloud gaming, and YouTube live streaming has been surging. To support these immersive or conversational applications, the importance of low-latency services for data packets transmitted over the Internet is emerging.

[0126] To enable low-latency services for data packets, congestion control along the end-to-end path must be possible. Through this congestion control, each server can prevent performance issues and provide normal services to users.

[0127] User equipment (UE) must be able to regulate packet throughput by properly reflecting the terminal's available capability (or capacity). However, conventional congestion control methods have the problem of being unable to regulate packet throughput in a scalable manner.

[0128] To resolve bottlenecks in these data packets and improve the user experience, Low Latency, Low Loss, and Scalable Throughput (L4S) technology was introduced in 3GPP Release 18. L4S is a new rate and congestion control technology for applications requiring low latency or capacity, and its core concepts are broadly classified into four categories.

[0129] The core concepts of L4S include closed-loop feedback control using explicit congestion signals, isolated network queues, Active Queue Management (AQM) capable of manipulating queue sizes to prevent large buffer sizes, and scalable congestion control features such as "Prague". Refer to the Internet Engineering Task Force Request for Comment (IETF RFC) for the core concepts of L4S.

[0130] Referring to FIG. 3a, Latency may include Propagation delay, Interface delay, and Queuing delay. The L4S technology described throughout this specification proposes a method to reduce Queuing delay.

[0131] Referring to FIG. 3b, the L4S operation may be as follows. First, the Radio Access Network (RAN) can identify congestion and transmit a data packet marked with congestion to an Application Server. Subsequently, the Application Server can transmit L4S feedback to a terminal based on the received data packet, and the terminal receiving the L4S feedback can apply the feedback to adjust the terminal's data transmission speed (or rate). The specific L4S operation will be described in detail in FIG. 4 below.

[0132] FIG. 4 is a diagram illustrating the specific operation of L4S (Low Latency, Low Loss, and Scalable throughput) communication according to one embodiment of the present disclosure.

[0133] With reference to Figure 4, the operation of Low Latency, Low Loss, and Scalable throughput (L4S) will be described. For specific L4S operations, refer to the Internet Engineering Task Force (IETF) Request For Comments (RFC).

[0134] The sender shown in FIG. 4 may include a terminal (User Equipment), the network device may include a base station, and the receiver may include a server, and each term may be used interchangeably.

[0135] In Step 1, the sender (e.g., terminal) and the receiver (e.g., server) can perform a negotiation procedure regarding L4S capability. (L4S capability negotiation)

[0136] More specifically, the terminal and the server can perform a negotiation process regarding whether the terminal and the network device (e.g., a base station) support L4S through actions such as a Transmission Control Protocol (TCP) handshake.

[0137] In step 2, the sender can transmit (or forward) a data packet containing an Explicit Congestion Notification-Capable Transport (ECT) bit to a network device.

[0138] More specifically, the terminal may use the Explicit Congestion Notification (ECN) bit in the Type Of Service (TOS) field of the IP header as a bit to mark congestion, and the ECN bit may be encoded as shown in [Table 1] below.

[0139] ValueCode point name Meaning 00 Non-ECT Does not support ECN transport (Non-ECN-capable transport) 01 ECT (0) Supports Classical ECN (ECN-capable transport) 10 ECT (1) L4S-capable (L4S-capable transport) 11 CE (Congestion Experience) Congestion experience (L4S packets that experienced Congestion)

[0140] If both the terminal and the base station can support L4S, the terminal can transmit data packets by performing an ECT bit setting process that signifies an L4S-capable transport.

[0141] In step 3, the network device can perform Congestion Experience (CE) bit settings.

[0142] More specifically, the base station can perform the CE bit setting process with a probability proportional to the terminal's queue state.

[0143] In step 4, the network device can transmit a data packet containing CE bits to the receiver.

[0144] More specifically, the base station can transmit a data packet to the server in which a CE bit indicating the congestion level is set.

[0145] In step 5, the receiver can perform congestion feedback based on a data packet containing the received CE bit.

[0146] More specifically, the server can provide feedback on the congestion level through messages such as TCP ACK (Acknowledgement) based on the ratio of ECN-marked packets.

[0147] In step 6, the sender can perform a speed control operation based on feedback received from the receiver.

[0148] More specifically, the terminal can perform speed control based on (or using) received Congestion Level information.

[0149] To improve the aforementioned L4S performance, frequent signaling and the resulting battery capacity must be supported. However, frequent signaling can lead to performance degradation. To address this problem, it is necessary to configure the base station so that the Congestion Metric Delivery does not use an excessively short interval. On the terminal side, it is necessary to adjust the Delivery Interval by considering the accuracy of congestion detection based on the outdated Congestion Metric.

[0150] In the present disclosure, a new Congestion Metric Delivery algorithm is proposed to solve the problems of current L4S technology. In particular, an opportunistic Congestion Metric Delivery algorithm is proposed by introducing conditions and threshold concepts that can reduce the overhead of Metric Delivery between DU-CU or CP-AP.

[0151] FIGS. 5a and 5b are drawings for explaining the operation of terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and base station determination L4S (BS-driven L4S) according to one embodiment of the present disclosure.

[0152] Before describing the present disclosure, we will define the Network-driven L4S, terminal determination L4S (UE-driven L4S), and base station determination L4S (BS-driven L4S) operations.

[0153] Network-driven L4S operation refers to the L4S operation introduced in the aforementioned 3GPP Release 18. More specifically, a base station (BS) obtains Buffer Status Report (BSR) information from a user equipment (UE), and subsequently, the base station determines the congestion status of the UE by transmitting a data packet containing a Congestion Experience (CE) bit based on the obtained BSR information.

[0154] However, there are limitations to the application of this network-driven L4S method. Network-driven L4S operation means that base stations can provide the service only in 5G standalone (SA) Radio Access Networks (RANs) that support 3GPP Release 18 L4S. In other words, L4S cannot be applied in 5G SA RANs that do not support 3GPP Release 18 L4S, such as Long Term Evolution (LTE) or 5G Non-Standalone (NSA) RANs.

[0155] To address these problems, the present disclosure proposes a method in which a specific entity controls Explicit Congestion Notification (ECN) or Rate independently. More specifically, the present specification proposes a method in which a User Equipment (UE) or a Base Station (BS) independently controls ECN or Rate. Hereinafter, this method will be referred to as "UE-driven L4S" or "BS-driven L4S".

[0156] For convenience of explanation, the “UE-driven L4S” operation is described based on the uplink (UL) data transmission operation of the terminal, the terminal’s communication processor (CP), and the application processor (AP), and the “BS-driven L4S” operation is described based on the downlink (DL) data transmission operation of the base station, the distributed unit (DU), and the centralized unit (CU), but the scope of the present invention is not limited thereto, and the same method may be applied to entities performing similar operations.

[0157] The operation of a UE-driven L4S (or a BS-driven L4S) proposed in this disclosure means a method in which the CP (or DU) of a UE (or BS) transmits metric information internally acquired by the CP (or DU) to the AP (or DU) through an interface between the CP (or DU) and the AP (or CU), and the AP (or CU) controls the ECN based on the acquired metric information, so that the UE (or BS) controls congestion on its own.

[0158] Below, we will explain the indicator information and the interface between CP (or DU) and AP (or CU), and explain the operation of UE-driven L4S and BS-driven L4S, respectively.

[0159] First, let us explain metric information. Metric information refers to quantitative criteria for measuring and evaluating network performance, efficiency, and user experience (Quality of Experience, QoE), and may be used interchangeably with terms such as "Metric," "Congestion Metric Information," "Congestion Metric," or "Congestion Metric." Metric information may include the following information.

[0160] - : Queue length information of the Layer 2 (L2) Tx buffer

[0161] - : Layer 1 (L1) / Layer 2 (L2) throughput information; if the rate decreases, it is considered a congestion situation.

[0162] - : Queue delay information of the L2 Tx buffer, Is / Calculated by

[0163] - : ECN marking probability, information on the probability with which the ECN will be marked

[0164] CP (or DU) and AP (or CU) cannot access each other because a unique memory space is allocated to each process. Therefore, CP (or DU) and AP (or CU) can transmit metric information (or Congestion Metric) through an interface. An interface can refer to a method or path for transmitting and receiving data.

[0165] The operation of a CP (or DU) transmitting metric information (or Congestion Metric) to an AP (or CU) through an interface may be referred to as "metric information delivery," "congestion metric information delivery," "congestion metric delivery," or "Congestion Metric Delivery."

[0166] The period or interval during which CP (or DU) transmits indicator information (or Congestion Metric) to AP (or CU) through an interface may be referred to as "Interval" or "Delivery Interval".

[0167] Referring to FIG. 5a, a terminal performing the operation of a UE-driven L4S may include a CP and an AP.

[0168] Referring to FIG. 5a, the CP of the terminal can perform the following operations.

[0169] 1. The above CP can measure and / or calculate first indicator information (or first Congestion Metric). At this time, the first indicator information (or first Congestion Metric) refers to (Queue length information of the L2 Tx buffer) and It may include (L1 / L2 throughput).

[0170] 2. The above CP may obtain (or calculate) second indicator information (or second Congestion Metric) based on (or utilizing) the first indicator information (or first Congestion Metric) measured and / or calculated. At this time, the second indicator information (or second Congestion Metric) refers to It may include (Queue delay), Is / It can be obtained (or calculated) through.

[0171] 3. The above CP can transmit the acquired second indicator information (or second Congestion Metric) to the AP through an interface.

[0172] Referring to FIG. 5a, the AP of the terminal can perform the following operations.

[0173] 1. The AP that has obtained the above-mentioned second indicator information (or second Congestion Metric) (Or ECN marking probability) can be calculated.

[0174] 2. The above AP is calculated ECN marking can be performed on the IP header based on (or ECN marking probability).

[0175] Through this, the above AP can perform ECN marking to perform congestion control or rate control operations.

[0176] Referring to FIG. 5b, a base station performing the operation of a BS-driven L4S may include a DU and a CU.

[0177] Referring to FIG. 5b, the DU of the base station can perform the following operations.

[0178] 1. The above DU can measure and / or calculate first indicator information (or first Congestion Metric). At this time, the first indicator information (or first Congestion Metric) refers to (Queue length information of the L2 Tx buffer) and It may include (L1 / L2 throughput).

[0179] 2. The above DU may acquire (or calculate) second indicator information (or second Congestion Metric) based on (or utilizing) the first indicator information (or first Congestion Metric) measured and / or calculated. At this time, the second indicator information (or second Congestion Metric) refers to It may include (Queue delay), Is / It can be obtained (or calculated) through.

[0180] 3. The above DU can transmit the acquired second indicator information (or second Congestion Metric) to the CU through an interface.

[0181] Referring to FIG. 5b, the CU of the base station can perform the following operations.

[0182] 1. The AP that has obtained the above-mentioned second indicator information (or second Congestion Metric) (Or ECN marking probability) can be calculated.

[0183] 2. The above CU is calculated ECN marking can be performed on the IP header based on (or ECN marking probability).

[0184] Through this, the CU can perform ECN marking to perform congestion control or rate control operations.

[0185] Meanwhile, when following the aforementioned UE-driven L4S or BS-driven L4S methods, a trade-off occurs in terms of the delivery of indicator information (or Congestion Metric Delivery) from the CP (or DU) to the AP (or CU). That is, if the delivery interval of indicator information (or Congestion Metric) between the CP (or DU) and the AP (or CU) becomes short, high-cost signaling occurs frequently in terms of battery consumption. On the other hand, if the delivery interval of indicator information (or Congestion Metric) between the CP and the AP becomes long, the accuracy of congestion detection decreases, leading to a degradation of L4S performance. Below, we propose specific methods to prevent L4S performance degradation.

[0186] FIG. 6 is a flowchart illustrating the overall sequence of terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0187] Referring to FIG. 6, the first device and the second device may refer to devices that support L4S in a communication system and may include terminal (UE) base stations and similar network devices. The first entity of the first device may include a communication processor (CP) of the terminal or a distributed unit (DU) of the base station, and the second entity of the first device may include an application processor (AP) of the terminal or a centralized unit (CU) of the base station.

[0188] Referring to step 610, information on changes in the metric for congestion control can be obtained from the first entity of the first device. Information on changes in the metric refers to the first metric information currently measured by the first entity of the first device ( ) and the most recently (or last) transmitted second indicator information transmitted from the first entity to the second entity ( It may mean a change between ). According to one embodiment of the present disclosure, the indicator information is as described above It can include a (delay) value.

[0189] Referring to step 620, at the first entity of the first device, based on information regarding a change in the Explicit Congestion Notification (ECN) marking probability (P) corresponding to information regarding a change in the indicator for congestion control, the currently measured first indicator information ( It can be determined whether to transmit ) to the second entity of the first device. First indicator information ( A specific method for determining whether to transmit ) to the second entity of the first device will be described later in FIGS. 7 to 9.

[0190] In step 630, if the first entity of the first device transmits the first indicator information to the second entity of the first device, the second entity of the first device may determine (or calculate) the value of the ECN marking probability corresponding to the acquired first indicator information. At this time, the second entity of the first device may use the mapping relationship between the first indicator information and the ECN marking probability.

[0191] In step 640, the second entity of the first device may transmit a packet marked with an ECN to the second device based on the determined (or calculated) ECN marking probability value.

[0192] FIG. 7 is a diagram illustrating a first embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0193] [1st Embodiment]

[0194] According to one embodiment of the present disclosure, a CP (or DU of a base station) of a terminal supporting UE-driven L4S operation (or BS-driven L4S operation) can determine whether to skip the delivery of indicator information (or Congestion Metric) to the AP (or CU of a base station) of the terminal based on the magnitude and / or degree of change in the ECN marking probability (P).

[0195] More specifically, when calculating the ECN marking probability (P) at the terminal's AP (or base station's CU), the terminal's AP (or base station's CU) may utilize the mapping relationship between the indicator information (or Congestion Metric) and the ECN marking probability (P) as shown in [Table 2] below. In this case, the mapping relationship between the indicator information (or Congestion Metric) and the ECN marking probability (Probability, P) can be either linear or non-linear.

[0196] Metric_old > Mapping > Probability_oldMetric_new > Mapping > Probability_new

[0197] Metric_new may refer to indicator information (or Congestion Metric) currently measured and transmitted from the terminal's CP (or base station's DU) to the terminal's AP (or base station's CU), and Metric_old may refer to indicator information (or Congestion Metric) transmitted immediately before (or recently) from the terminal's CP (or base station's DU) to the terminal's AP (or base station's CU). On the other hand, the terminal's CP (or base station's DU) does not need to know information regarding changes in these ECN marking probabilities (P), and can operate in the same way as the present proposal by knowing only the information regarding changes in the Metric in a specific interval and the mapping information between the Probability (P or ECN marking probabilities).

[0198] The terminal's CP (or base station's DU) can determine whether to deliver indicator information (Metric_new) (or Congestion Metric) to the terminal's AP (or base station's CU) based on the difference between Probability_old and Probability_new obtained from the change information of Metric_old and Metric_new.

[0199] According to one embodiment of the present disclosure, the concept of Skip Threshold (or Skip_Threshold) is proposed to determine whether to omit the delivery of indicator information (or Congestion Metric) from the terminal's CP (or base station's DU) to the terminal's AP (or base station's CU).

[0200] Skip Threshold may refer to a threshold value used to determine whether to transmit Metric_new. More specifically, if the delta value, which represents the difference between Metric_new and Metric_old, is greater than the Skip Threshold, the terminal's CP (or base station's DU) transmits the indicator information (or Congestion Metric) to the terminal's AP (or base station's CU), and if the delta value is less than the Skip Threshold, the transmission of the indicator information is omitted.

[0201] Referring to FIG. 7, the terminal's CP (or base station's DU) can determine a change in P (or ECN marking probability) through a mapping relationship of indicator information (or Congestion Metric information) that includes a linear section. At this time, the terminal's CP (or base station's DU) is in a state where it does not have information about the probability change, and it performs delivery of the indicator information (or Congestion Metric) only when the probability change is above a specific threshold value (or a certain degree).

[0202] Although the description in Fig. 7 is based on a linear mapping relationship, the scope of the present invention is not limited thereto and can be applied in the same way to other types of mapping relationships.

[0203] Below, we will explain the case where the metric information (or Congestion Metric) to be transmitted is the Tx queue delay (or delay, ).

[0204] d_new in FIG. 7 is a metric information (or Congestion Metric) that determines whether to transmit from the terminal's CP (or base station's DU) to the terminal's AP (or base station's CU), and may mean the currently measured metric information (or Congestion Metric), and d_last may mean the metric information (or Congestion Metric) that was most recently (or immediately before) transmitted from the terminal's CP (or base station's DU) to the terminal's AP (or base station's CU).

[0205] Th1 may represent the maximum threshold value at which the ECN marking probability (P) corresponding to the delay value corresponds to p_low, and Th2 may represent the minimum threshold value at which the ECN probability (P) corresponding to the delay value corresponds to p_high.

[0206] Skip_threshold may refer to the threshold value of the metric information that serves as a criterion for determining whether to skip the measured metric information (or Congestion Metric).

[0207] 1. go If less than (0≤ < )

[0208] (1) (0≤ < ) Skip

[0209] - every Since it is a section, skip without conditions

[0210] (2) ( ≤ < ) Delivery

[0211] - Delivery unconditionally as it advances through the section

[0212] (3) ( ≤ ) Delivery

[0213] - Delivery unconditionally as it advances through the section

[0214] 2. go That is all, If less than ( ≤ < )

[0215] (1) (0≤ < ) Delivery

[0216] - Delivery unconditionally due to entry into the interval

[0217] (2) ( ≤ < ) & ( <Skip_threshold) 생략 (Skip)

[0218] - Judgment based on conditions, i.e. and Skip if the difference is less than or equal to Skip_threshold

[0219] (3) ( ≤ ) & ( <Skip_threshold) 생략 (Skip)

[0220] - Judgment based on conditions, go In the case of abnormalities and Since there is no change in the corresponding ECN marking probability, (or )and Skip if the difference is less than or equal to Skip_threshold

[0221] 3. go In the case of abnormalities ( ≤ )

[0222] (1) (0≤ < ) Delivery

[0223] - Since it enters the interval, delivery is made unconditionally.

[0224] (2) ( ≤ < ) & ( < Skip_threshold) Omit (Skip)

[0225] - Judgment based on conditions, go In the case of abnormalities and Since there is no change in the corresponding ECN marking probability, (or )and Skip if the difference is less than or equal to Skip_threshold

[0226] (3) ( ≤ ) Skip

[0227] - every Since it is a section, skip without conditions

[0228] This is a drawing for explaining a second embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0229] [2nd Embodiment]

[0230] According to another embodiment of the present disclosure, in UE-driven L4S (or BS-driven L4S) operation, the Skip Threshold may be applied differently depending on the area (or interval) of the indicator information (or Congestion Metric). This is because the Skip Threshold needs to be introduced at various multi-levels depending on importance or sensitivity.

[0231] For example, in cases sensitive to outdated congestion metric, it is necessary to apply a relatively low Skip Threshold. This is because, when the transmission period (or interval) of Congestion Metric Delivery is long, the terminal's AP (or base station's CU) performs ECN marking based on the outdated congestion metric. In this case, the terminal's AP (or CU) may operate with the timing for performing ECN marking on data packets reversed, so it is necessary to change and apply the Skip Threshold.

[0232] As another example, it is necessary to apply a relatively low Skip Threshold (or threshold) in the region approaching the terminal's Target Tx queue delay, as the decision regarding ECN marking may vary. This is because ECN marking is required when the Tx queue delay is greater than or equal to the Target Tx queue delay, but is not required when the Tx queue delay is smaller than the Target Tx queue delay. In other words, the Skip Threshold needs to be adjusted at points where the decision to mark ECN—rather than the probability of the ECN mark—is critical.

[0233] As another example, a relatively low Skip Threshold needs to be applied in areas with a high ECN marking probability because throughput underutilization may occur. Since a higher ECN marking probability indicates worsening congestion, the system operates to process packets at a rate lower than capacity; however, because L4S application is premised on preventing terminal performance degradation, packet throughput control is necessary to maintain throughput.

[0234] To solve these problems, the present disclosure proposes a method of applying a Skip Threshold in various ways depending on the region to which the value of the indicator information (or Congestion Metric) belongs. In other words, a terminal (or base station) operating as a UE-driven L4S (or BS-driven L4S) according to one embodiment of the present disclosure can dynamically (or adaptively) determine whether to transmit the indicator information (or Congestion Metric) depending on the region to which the value of the indicator information (or Congestion Metric) belongs. For reference, the value of the Skip Threshold can be applied and determined in various ways considering the system environment.

[0235] The method of applying the Skip Threshold according to the region to which the value of the metric information (or Congestion Metric) belongs can be expressed as shown in Table 3 below.

[0236]

[0237] Referring to Fig. 8, this Assuming it is larger, in a specific region It is applied, and in another specific area It can be applied.

[0238] Referring to Fig. 8, In the area where this applies, △m( )Is Since it is greater than the value, it conveys metric information (or congestion metric), but △m( In ) Because it is smaller than the value, it does not convey metric information (or congestion metric).

[0239] the other side, In the region where this applies, △m( ) and △m( +6) Since it is greater than the value, it can convey metric information (or congestion metric). In particular, △m in the area where this applies ( +1) value and △m in the area where this applies ( Even if the value of +6) is the same, the transmission of indicator information may differ because the applied Skip Threshold value follows.

[0240] FIGS. 9a and 9b are drawings for illustrating a third embodiment when performing terminal determination L4S (Low Latency, Low Loss, and Scalable throughput) (UE-driven L4S) and / or (UE-driven L4S) and / or base station determination L4S (BS-driven L4S) operations according to one embodiment of the present disclosure.

[0241] [Third Embodiment]

[0242] According to another embodiment of the present disclosure, in the operation of a UE-driven L4S (or BS-driven L4S), a changeable Adaptive Interval concept for the delivery of indicator information (or Congestion Metric Delivery) may be introduced. More specifically, in the operation of a UE-driven L4S (or BS-driven L4S), the delivery of indicator information (or Congestion Metric Delivery) may be performed by considering (or reflecting) the speed of channel state change between the terminal and the base station.

[0243] Referring to Fig. 9a, the speed of channel state change between the terminal and the base station may increase due to the increased movement speed of the terminal. When the speed of channel state change between the terminal and the base station increases, congestion detection needs to be performed faster. Therefore, the terminal's CP (or the base station's DU) needs to reduce the delivery cycle (or interval) of the indicator information delivery (or Congestion Metric Delivery).

[0244] Conversely, due to a decrease in the terminal's movement speed, the speed of channel state changes between the terminal and the base station may decrease. If the speed of channel state changes between the terminal and the base station decreases, there is no need for rapid congestion detection, so it is necessary to increase the delivery cycle (or interval) of indicator information (or Congestion Metric Delivery). If the delivery cycle of indicator information (or Congestion Metric Delivery) increases, the number (or count) of indicator information delivery (or Congestion Metric Delivery) may decrease.

[0245] Referring to Fig. 9b, when the speed of channel state change between the terminal and the base station increases, it is necessary to perform congestion detection more quickly. In this case, the interval of congestion metric delivery is reduced, and the number of delivery of congestion metric information (or Delivery Count) can be increased.

[0246] On the other hand, when the speed of channel state change decreases, there is no need to perform congestion detection quickly. In such cases, increasing the interval of congestion metric delivery (or congestion metric delivery) has the effect of reducing the number of delivery counts (or delivery count).

[0247] FIG. 10 is a drawing for explaining the initial connection process of a terminal according to one embodiment of the present disclosure.

[0248] [Example 4]

[0249] According to another embodiment of the present disclosure, a method is proposed for a CU-CP of a base station to set an ECN Marking Skip Threshold and a Delivery Interval when performing a Network-driven L4S operation. The terminal may transmit information regarding the ECN Marking Skip Threshold and the ECN Marking Delivery Interval during the initial access process (UE Initial Access process).

[0250] According to one embodiment of the present disclosure, gNB-CU-CP proposes a method of transmitting the ECN Marking Skip Threshold and Delivery Interval between gNB-CU-UP and Bearer Context Setup through a Bearer Context Setup procedure. Additionally, between gNB-CU-CP and gNB-DU, a method of transmitting the ECN Marking Skip Threshold and Delivery Interval through a UE Context Setup procedure is proposed.

[0251] More specifically, during the UE Initial Access process, by utilizing Bearer Context Setup request / Response and UE Context Setup request / Response messages, an IE that can include the ECN Marking Skip Threshold and Delivery Interval can be added to transmit and receive the information in an enumerated form.

[0252] In one embodiment of the present disclosure, a method for gNB-CU-CP to specify values ​​for ECN Marking Skip Threshold and Delivery Interval (Method 1, 4-1 embodiment) and a method for setting candidates for values ​​for ECN Marking Skip Threshold and Delivery Interval (or a recommended method, Method 2, 4-2 embodiment) are proposed.

[0253] To explain the present disclosure, FIG. 10 describes the initial connection process of a terminal, FIG. 11a to FIG. 11c describe Method 1, and FIG. 12a to FIG. 12c describe Method 2 in detail.

[0254] Referring to FIG. 10, the initial connection process of the terminal is as follows. Specific details of the initial connection process of the terminal can be found in 3GPP TS 37.483 and TS 38.473.

[0255] In step 1, the terminal (User Equipment, UE, 1001) can send an RRC Setup Request message to the gNB-distributed unit (gNB-DU, 1003).

[0256] In step 2, the gNB-DU (1003) that receives the RRC Setup Request message can send an initial uplink radio resource control (RRC) message to the gNB-centralized unit-user plane (gNB-CU-UP, 1005).

[0257] In step 3, the gNB-CU-CP (1005) can send a downstream RRC message to the gNB-DU (1003).

[0258] In step 4, the gNB-DU (1003) can send an RRC Setup message to the UE (1001).

[0259] In step 5, the UE (1001) can send an RRC Setup complete message to the gNB-DU (1003).

[0260] In step 6, the gNB-DU (1003) can send a UL RRC message to the gNB-CU-CP (1005).

[0261] Step 7: The gNB-CU-CP (1005) can send an Initial UE message to the Access and Mobility Management Function (AMF, 1009), and Step 8: The AMF (1009) can send an Initial Context Setup request message to the gNB-CU-CP (1005).

[0262] Step 9, the gNB-CU-CP (1005) that receives the above Initial Context Setup request message can send a Bearer Context Setup request message to the gNB-centralized unit-user plane (gNB-CU-UP, 1007).

[0263] In step 10, the gNB-CU-UP (1007) can send a Bearer Context Setup Response message to the gNB-CU-CP (1005).

[0264] In step 11, the gNB-CU-CP (1005) that receives the Bearer Context Setup Response message can send a UE Context Setup request message to the gNB-DU (1003).

[0265] In step 13, the gNB-DU (1003) can send a UE Context Setup Response message.

[0266] FIGS. 11a, 11b, and 11c are drawings for illustrating a 4-1 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0267] More specifically, FIGS. 11a to 11c are drawings for explaining (Method 1) in which the aforementioned gNB-CU-CP specifies the values ​​of the ECN Marking Skip Threshold and Delivery Interval.

[0268] Referring to FIGS. 11a through 11c, the Centralized Unit-Control Plane (CU-CP, 1005) can perform a Bearer Context Setup procedure with the Centralized Unit-User Plane (CU-UP, 1007).

[0269] In step 9, the CU-CP (1005) may include specific values ​​of the ECN Marking Skip Threshold (e.g., 0, 1, 2, 3, ...) and specific values ​​of the ECN Marking Delivery Interval (0, 50, 100, 200, ...) in an enumerated form in the bearer Context Setup Request message sent to the CU-UP (1007).

[0270] In step 10, since the CU-UP (1007) has received a specific value of the ECN Marking Skip Threshold and a specific value of the ECN Marking Delivery Interval through the Bearer Context Setup Request message, the Bearer Context Setup Response message may be transmitted without including any information regarding the ECN Marking Skip Threshold and ECN Marking Delivery Interval, and only information indicating whether the ECN Marking is active or not active.

[0271] Likewise, referring to FIGS. 11a through 11c, CU-CP (1005) can perform the UE Context Setup procedure with the Distributed Unit (DU, 1003).

[0272] In step 11, the CU-CP (1005) may include specific values ​​of the ECN Marking Skip Threshold (e.g., 0, 1, 2, 3, ...) and specific values ​​of the ECN Marking Delivery Interval (0, 50, 100, 200, ...) in an enumerated form in the UE Context Setup Request message transmitted to the DU (1003).

[0273] In step 13, since the DU (1003) has received a specific value of the ECN Marking Skip Threshold and a specific value of the ECN Marking Delivery Interval through the UE Context Setup Request message, the UE Context Setup Response message may be transmitted without including any information regarding the ECN Marking Skip Threshold and ECN Marking Delivery Interval, and only information indicating whether the ECN Marking is active or not active.

[0274] FIGS. 12a, 12b, and 12c are drawings for illustrating a 4-2 embodiment when performing a Network-driven L4S operation according to one embodiment of the present disclosure.

[0275] More specifically, FIGS. 12a to 12c are drawings for explaining (Method 2) in which the aforementioned gNB-CU-CP recommends values ​​for the ECN Marking Skip Threshold and ECN Marking Delivery Interval.

[0276] Referring to FIGS. 12a through 12c, the Centralized Unit-Control Plane (CU-CP, 1005) can perform a Bearer Context Setup procedure with the Centralized Unit-User Plane (CU-UP, 1007).

[0277] In step 9, the CU-CP (1005) may transmit a Bearer Context Setup Request message to the CU-UP (1007) containing at least one candidate value for an ECN Marking Skip Threshold (e.g., 0, 1, 2, 3, ...) and at least one candidate value for an ECN Marking Delivery Interval (e.g., 0, 50, 100, 200, ...) in an enumerated form. Alternatively, it may transmit all supported values ​​for an ECN Marking Skip Threshold and all supported values ​​for an ECN Marking Delivery Interval.

[0278] In step 10, the CU-UP (1007) may send a Bearer Context Setup Response message to the CU-CP (1005). The Bearer Context Setup Response message may be sent including information indicating whether the ECN Marking is active or not active, along with at least one candidate value for the ECN Marking Skip Threshold and at least one candidate value for the ECN Marking Interval, including a specific value for the ECN Marking Skip Threshold and a specific value for the ECN Marking Delivery Interval that are actually supported.

[0279] Likewise, referring to FIGS. 12a through 12c, CU-CP (1005) can perform the UE Context Setup procedure with the Distributed Unit (DU, 1003).

[0280] In step 11, the CU-CP (1005) may transmit a UE Context Setup Request message to the DU (1003) containing at least one candidate value for an ECN Marking Skip Threshold (e.g., 0, 1, 2, 3, ...) and at least one candidate value for an ECN Marking Delivery Interval (e.g., 0, 50, 100, 200, ...) in an enumerated form. Alternatively, it may transmit all supported values ​​for an ECN Marking Skip Threshold and all supported values ​​for an ECN Marking Delivery Interval.

[0281] In step 13, the DU (1003) may send a UE Context Setup Response message to the CU-CP (1005). The UE Context Setup Response message may be sent including information indicating whether the ECN Marking is active or not active, along with at least one candidate value for the ECN Marking Skip Threshold and at least one candidate value for the ECN Marking Interval, including a specific value for the ECN Marking Skip Threshold and a specific value for the ECN Marking Delivery Interval that are actually supported.

[0282] FIGS. 13a and FIGS. 13b are drawings for explaining the effects of the invention according to one embodiment of the present disclosure.

[0283] FIGS. 13a and 13b are drawings illustrating the effect of applying a Skip Threshold by introducing the terminal determination L4S (UE-driven L4S) and base station determination L4S (BS-driven L4S) operations proposed in the present disclosure. More specifically, FIGS. 13a and 13b are drawings illustrating the reduction in the count of indicator information delivery (or Congestion Metric Delivery) when a Skip Threshold is applied in the same Interval environment.

[0284] The effects of reducing the count of Congestion Metric Delivery are as follows. First, the signaling itself on the interface between the CP (or DU) and the AP (or CU) can be reduced. Second, the computational load of the CP (or DU) and the AP (or CU) can be reduced.

[0285] Referring to Fig. 13a, let's assume the delivery interval is 50ms.

[0286] First, in the case of terminal determination L4S (UE-driven L4S) operation where Skip Threshold is not applied, arithmetically 600 delivery of metric information (or Congestion Metric Delivery) must be performed over 30 seconds.

[0287] On the other hand, when a Skip Threshold of 2ms is applied according to the terminal decision L4S (UE-driven L4S) operation, it can be seen that 181 delivery of metric information (or Congestion Metric Delivery) were performed over 30s. This is a result similar to the case where the Delivery Interval is 166ms and no Skip Threshold is applied, and it implies a benefit of approximately 70% reduction in the Delivery count.

[0288] When a Skip Threshold of 6ms is applied according to the terminal determination L4S (UE-driven L4S) operation, it can be seen that 113 delivery of metric information (or Congestion Metric Delivery) were performed over 30s. This is a result similar to the case where the Delivery Interval is 265ms and no Skip Threshold is applied, and it means a benefit of approximately 81% reduction in the Delivery count.

[0289] Referring to Fig. 13b, let's assume the delivery interval is 1000ms.

[0290] First, in the case of terminal determination L4S (UE-driven L4S) operation where Skip Threshold is not applied, 300 delivery of metric information (or Congestion Metric Delivery) must be performed arithmetically over 30 seconds.

[0291] On the other hand, when a Skip Threshold of 2ms is applied according to the terminal decision L4S (UE-driven L4S) operation, it can be seen that 103 delivery of metric information (or Congestion Metric Delivery) were performed over 30s. This is a result similar to the case where the Delivery Interval is 291ms and no Skip Threshold is applied, and it implies a benefit of approximately 66% reduction in the Delivery count.

[0292] When a Skip Threshold of 6ms is applied according to the terminal determination L4S (UE-driven L4S) operation, it can be seen that 61 delivery of metric information (or Congestion Metric Delivery) were performed over 30s. This is a result similar to the case where the Delivery Interval is 492ms and no Skip Threshold is applied, and it implies a benefit of approximately 80% reduction in the Delivery count.

[0293] FIG. 14 is a drawing illustrating the internal structure of a terminal according to one embodiment of the present disclosure.

[0294] Referring to FIG. 14, the terminal (user equipment, UE) may include an RF (Radio Frequency) processing unit (14-10), a baseband processing unit (14-20), a storage unit (14-30), and a control unit (14-40).

[0295] The RF processing unit (14-10) can perform functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (14-10) can up-convert a baseband signal provided by the baseband processing unit (14-20) into an RF band signal and transmit it through an antenna, and down-convert an RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (14-10) may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC (digital to analog converter), an ADC (analog to digital converter), etc. Although only one antenna is shown in the drawing, the terminal may be equipped with multiple antennas. In addition, the RF processing unit (14-10) may include multiple RF chains. Furthermore, the RF processing unit (14-10) may perform beamforming. For the above beamforming, the RF processing unit (14-10) can adjust the phase and magnitude of each of the signals transmitted and received through multiple antennas or antenna elements. In addition, the RF processing unit can perform MIMO (multiple input multiple output) and can receive multiple layers when performing MIMO operation.

[0296] The baseband processing unit (14-20) can perform a conversion function between a baseband signal and a bit sequence according to the physical layer specifications of the system. For example, when transmitting data, the baseband processing unit (14-20) can generate complex symbols by encoding and modulating the transmitted bit sequence. Additionally, when receiving data, the baseband processing unit (14-20) can restore the received bit sequence by demodulating and decoding the baseband signal provided by the RF processing unit (14-10). For example, in the case of following the OFDM (orthogonal frequency division multiplexing) method, when transmitting data, the baseband processing unit (14-20) generates complex symbols by encoding and modulating the transmitted bit sequence, maps the complex symbols to subcarriers, and then constructs OFDM symbols through IFFT (inverse fast Fourier transform) operation and CP (cyclic prefix) insertion. Additionally, upon receiving data, the baseband processing unit (14-20) can divide the baseband signal provided from the RF processing unit (14-10) into OFDM symbol units, restore the signals mapped to subcarriers through FFT (fast Fourier transform) operations, and then restore the received bit sequence through demodulation and decoding.

[0297] The baseband processing unit (14-20) and the RF processing unit (14-10) can transmit and receive signals as described above. Accordingly, the baseband processing unit (14-20) and the RF processing unit (14-10) may be referred to as a transmitting unit, a receiving unit, a transmitting and receiving unit, or a communication unit. Furthermore, at least one of the baseband processing unit (14-20) and the RF processing unit (14-10) may include a plurality of communication modules to support a plurality of different wireless access technologies. Additionally, at least one of the baseband processing unit (14-20) and the RF processing unit (14-10) may include different communication modules to process signals of different frequency bands. For example, the different wireless access technologies may include wireless LAN (e.g., IEEE 802.11), cellular network (e.g., LTE), etc. In addition, the above different frequency bands may include super high frequency (SHF) bands (e.g., 2 NRHz, NRHz) and millimeter wave (e.g., 60 GHz) bands.

[0298] The control unit (14-40) controls the overall operations of the terminal. For example, the control unit (14-40) transmits and receives signals through the baseband processing unit (14-20) and the RF processing unit (14-10). Additionally, the control unit (14-40) writes and reads data to and from the storage unit (14-30). To this end, the control unit (14-40) may include at least one processor. For example, the control unit (14-40) may include a communication processor (CP) that performs control for communication and an application processor (AP) that controls upper layers such as applications.

[0299] FIG. 15 is a drawing illustrating the internal structure of a base station according to one embodiment of the present disclosure.

[0300] Referring to FIG. 15, a base station (BS) may include an RF (Radio Frequency) processing unit (15-10), a baseband processing unit (baseband) (15-20), a storage unit (15-30), and a control unit (15-40).

[0301] The RF processing unit (15-10) can perform functions for transmitting and receiving signals through a wireless channel, such as signal band conversion and amplification. That is, the RF processing unit (15-10) upconverts the baseband signal provided by the baseband processing unit (15-20) into an RF band signal, transmits it through an antenna, and downconverts the RF band signal received through the antenna into a baseband signal. For example, the RF processing unit (15-10) may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc. Although only one antenna is shown in the drawing, the base station may be equipped with multiple antennas. In addition, the RF processing unit (15-10) may include multiple RF chains. Furthermore, the RF processing unit (15-10) may perform beamforming. For the above beamforming, the RF processing unit (15-10) can adjust the phase and magnitude of each of the signals transmitted and received through a plurality of antennas or antenna elements. The RF processing unit can perform down-to-down MIMO operation by transmitting one or more layers.

[0302] The baseband processing unit (15-20) can perform a conversion function between a baseband signal and a bit sequence according to the physical layer specifications. For example, when transmitting data, the baseband processing unit (15-20) can generate complex symbols by encoding and modulating the transmitted bit sequence. Additionally, when receiving data, the baseband processing unit (15-20) can restore the received bit sequence by demodulating and decoding the baseband signal provided by the RF processing unit (15-10). For example, in the case of following the OFDM method, when transmitting data, the baseband processing unit (15-20) generates complex symbols by encoding and modulating the transmitted bit sequence, maps the complex symbols to subcarriers, and then constructs OFDM symbols through IFFT operation and CP insertion. Additionally, upon receiving data, the baseband processing unit (15-20) can divide the baseband signal provided by the RF processing unit (15-10) into OFDM symbol units, restore the signals mapped to subcarriers through FFT operation, and then restore the received bit sequence through demodulation and decoding.

[0303] The baseband processing unit (15-20) and the RF processing unit (15-10) transmit and receive signals as described above. Accordingly, the baseband processing unit (15-20) and the RF processing unit (15-10) may be referred to as a transmitting unit, a receiving unit, a transmitting and receiving unit, a communication unit, or a wireless communication unit. Furthermore, at least one of the baseband processing unit (15-20) and the RF processing unit (15-10) may include a plurality of communication modules to support a plurality of different wireless access technologies. Additionally, at least one of the baseband processing unit (15-20) and the RF processing unit (15-10) may include different communication modules to process signals of different frequency bands. For example, the different wireless access technologies may include wireless LAN (e.g., IEEE 802.11), cellular network (e.g., LTE), etc. In addition, the above different frequency bands may include super high frequency (SHF) bands (e.g., 2 NRHz, NRHz) and millimeter wave (e.g., 60 GHz) bands.

[0304] The storage unit (15-30) can store data such as basic programs, application programs, and configuration information for the operation of the base station. In particular, the storage unit (15-30) can store information regarding a bearer assigned to a connected terminal, measurement results reported from the connected terminal, etc. Additionally, the storage unit (15-30) can store information that serves as a criterion for determining whether to provide or disconnect multiple connections to the terminal. Furthermore, the storage unit (15-30) can provide the stored data upon a request from the control unit (15-40).

[0305] The control unit (15-40) can control the overall operations of the base station. For example, the control unit (15-40) can transmit and receive signals through the baseband processing unit (15-20) and the RF processing unit (15-10). Additionally, the control unit (15-40) writes and reads data to and from the storage unit (15-30). To this end, the control unit (15-40) may include at least one processor.

[0306] Methods according to the embodiments described in the claims or specification of the present invention may be implemented in the form of hardware, software, or a combination of hardware and software.

[0307] When implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. One or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present invention.

[0308] Such programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, ROM (Read Only Memory), Electrically Erasable Programmable Read Only Memory (EEPROM), magnetic disc storage devices, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or other forms of optical storage devices, magnetic cassettes. Alternatively, they may be stored in memory composed of some or all of these. Additionally, each constituent memory may include multiple units.

[0309] In addition, the above program may be stored on an attachable storage device that can be accessed via a communication network such as the Internet, Intranet, LAN (Local Area Network), WLAN (Wide LAN), or SAN (Storage Area Network), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present invention through an external port. Additionally, a separate storage device on a communication network may be connected to a device performing an embodiment of the present invention.

[0310] In the specific embodiments of the present invention described above, the components included in the invention are expressed in a singular or plural form according to the specific embodiments presented. However, the singular or plural expression is selected to suit the situation presented for convenience of explanation, and the present invention is not limited to singular or plural components; even if a component is expressed in the plural form, it may be composed in the singular form, or even if a component is expressed in the singular form, it may be composed in the plural form.

[0311] Meanwhile, although specific embodiments have been described in the detailed description of the present invention, it is understood that various modifications are possible within the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the claims set forth below as well as equivalents thereof.

Claims

1. A method performed by a first device comprising a first entity and a second entity in a mobile communication system, A step of obtaining information on changes in an indicator (Metric) for congestion control from a first entity of the first device; A step of determining whether to transmit currently measured first indicator information (d_new) to the second entity of the first device based on change information of an Explicit Congestion Notification (ECN) marking probability (P) corresponding to change information of the indicator in the first entity of the first device; When the first indicator information is transmitted to the second entity of the first device, the second entity of the first device determines the value of an ECN marking probability corresponding to the first indicator information; and A method characterized by including the step of transmitting a packet marked with an ECN to a second device based on the determined ECN marking probability value.

2. In Paragraph 1, The change information of the above indicator refers to the change between the first indicator information currently measured and the second indicator information (d_last) last transmitted to the second entity, and A method characterized in that the threshold value of the reference indicator used to determine whether to transmit the above-mentioned first indicator information is a skip threshold value (Skip_threshold).

3. In Paragraph 2, If the above second indicator information (d_last) is less than the first threshold value (Th1): If the above first indicator information is less than the above first threshold value, the above first indicator information is not transmitted, and If the first indicator information is greater than or equal to the first threshold value and less than the second threshold value, the first indicator information is transmitted, and If the above first indicator information is greater than or equal to the above second threshold value, the above first indicator information is transmitted, and If the above second indicator information is greater than or equal to the first threshold value and less than the above second threshold value: If the above first indicator information is less than the above first threshold value, the above first indicator information is transmitted, and If the first indicator information is greater than or equal to the first threshold value and less than the second threshold value, or if the difference between the first indicator information and the second indicator information is greater than or equal to the omission threshold value, the first indicator information is transmitted. If the first indicator information is greater than or equal to the second threshold value, and if the difference between the second threshold value and the second indicator information is greater than or equal to the skip threshold value (Skip_threshold), the first indicator information is transmitted, and If the above second indicator information is greater than or equal to the above second threshold value: If the above first indicator information is less than the above first threshold value, the above first indicator information is transmitted, and If the first indicator information is greater than or equal to the first threshold and less than the second threshold, and if the difference between the second threshold and the first indicator information is greater than or equal to the skip threshold (Skip_threshold), the first indicator information is transmitted, and A method characterized by not transmitting the first indicator information when the first indicator information is greater than or equal to the second threshold value.

4. In Paragraph 2, A method characterized in that the above skip threshold value (Skip_threshold) varies depending on the region.

5. In Paragraph 1, A method characterized in that the period for transmitting the first indicator information to the second entity of the first device is determined based on the rate of change of the channel environment of the first device.

6. In Paragraph 1, The above indicator information includes delay information (d) of the Layer 2 (L2) transmission buffer, and A method characterized in that the above delay information is a value obtained by dividing the length information of the L2 transmission buffer by the Layer 1 (L1) and L2 throughput information.

7. In Paragraph 1, The first device above includes a terminal (User Equipment, UE), and The first entity of the first device includes a communication processor (CP), and The second entity of the first device includes an application processor (AP), and A method characterized in that the above-mentioned second device includes a base station.

8. In Paragraph 1, The above first device includes a base station, and The first entity of the first device includes a distributed unit (DU), and The second entity of the first device includes a central unit (CU), and A method characterized in that the above-mentioned second device includes a terminal.

9. In a first device in a mobile communication system, The first device includes a first entity and a second entity, and In the first entity of the first device, Acquire information on changes in metrics for congestion control, and Based on the change information of the Explicit Congestion Notification (ECN) marking probability (P) corresponding to the change information of the above indicator, it is determined whether to transmit the currently measured first indicator information (d_new) to the second entity of the first device, and In the second entity of the first device, When the above first indicator information is transmitted to the second entity of the above first device, the value of the ECN marking probability corresponding to the above first indicator information is determined, and A first device characterized by transmitting a packet marked with an ECN to a second device based on the above-determined ECN marking probability value.

10. In Paragraph 9, The change information of the above indicator refers to the change between the first indicator information currently measured and the second indicator information (d_last) last transmitted to the second entity, and A first device characterized in that the threshold value of the reference indicator used to determine whether to transmit the above-mentioned first indicator information is a skip threshold value (Skip_threshold).

11. In Clause 10, the first entity of the first device is, If the above second indicator information (d_last) is less than the first threshold value (Th1): If the above first indicator information is less than the above first threshold value, the above first indicator information is not transmitted, and If the first indicator information is greater than or equal to the first threshold value and less than the second threshold value, the first indicator information is transmitted, and If the above first indicator information is greater than or equal to the above second threshold value, the above first indicator information is transmitted, and If the above second indicator information is greater than or equal to the first threshold value and less than the above second threshold value: If the above first indicator information is less than the above first threshold value, the above first indicator information is transmitted, and If the first indicator information is greater than or equal to the first threshold value and less than the second threshold value, or if the difference between the first indicator information and the second indicator information is greater than or equal to the omission threshold value, the first indicator information is transmitted. If the first indicator information is greater than or equal to the second threshold value, and if the difference between the second threshold value and the second indicator information is greater than or equal to the skip threshold value (Skip_threshold), the first indicator information is transmitted, and If the above second indicator information is greater than or equal to the above second threshold value: If the above first indicator information is less than the above first threshold value, the above first indicator information is transmitted, and If the first indicator information is greater than or equal to the first threshold and less than the second threshold, and if the difference between the second threshold and the first indicator information is greater than or equal to the skip threshold (Skip_threshold), the first indicator information is transmitted, and A first device characterized by not transmitting the first indicator information when the first indicator information is greater than or equal to the second threshold value.

12. In Paragraph 10, A first device characterized in that the above skip threshold value (Skip_threshold) varies depending on the region.

13. In Paragraph 9, The period for transmitting the above-mentioned first indicator information to the second entity of the first device is determined based on the rate of change of the channel environment of the first device, and The above indicator information includes delay information (d) of the Layer 2 (L2) transmission buffer, and A first device characterized in that the above delay information is a value obtained by dividing the length information of the L2 transmission buffer by the Layer 1 (L1) and L2 throughput information.

14. In Paragraph 9, The first device above includes a terminal (User Equipment, UE), and The first entity of the first device includes a communication processor (CP), and The second entity of the first device includes an application processor (AP), and The first device is characterized by including a base station in the second device.

15. In Paragraph 9, The above first device includes a base station, and The first entity of the first device includes a distributed unit (DU), and The second entity of the first device includes a central unit (CU), and The first device is characterized by including a terminal in the second device.

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