Method and apparatus for accessing traffic steering, switching and diverting redundant traffic steering modes

Abstract

Provided are processes, methods, etc. involving access traffic steering, switching, and offloading redundant traffic steering modes. A method may include: sending information indicating a request to establish / modify a multi-access protocol data unit (PDU) session to a first network element; receiving a response indicating the request to establish / modify the multi-access PDU session via a second network element; determining a first value and a second value of a plurality of metrics of a first access network (AN) and a second access network; determining, based on a rule and the first value and the second value of the plurality of metrics satisfying a corresponding condition of the rule, to send a PDU associated with the multi-access PDU session via (i) the first AN, (ii) the second AN, or (iii) one of the first AN and the second AN; and sending the PDU via the first AN, the second AN, or the one of the first AN and the second AN.

Description

[0001] This divisional application is a divisional application with a filing date of January 27, 2023, an application number of 202380023294.7, and an invention name of “Method and device for access traffic steering, switching and diversion (ATSSS) redundant traffic steering mode”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of (i) U.S. Provisional Patent Application No. 63 / 303,722, filed on January 27, 2022, and (ii) U.S. Provisional Patent Application No. 63 / 411,546, filed on September 9, 2022, each of which is incorporated herein by reference. Background Art

[0004] The present disclosure relates to communications related to multiple access networks (also referred to as "access networks") of one or more communication systems, including but not exclusively to methods, devices, systems, etc. for access traffic steering, switching and splitting (ATSSS) redundant traffic steering mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A more detailed understanding can be obtained from the following detailed description, which is given by way of example in conjunction with its accompanying drawings. As with the detailed description, the figures in such drawings are exemplary. Therefore, the drawings and specific embodiments should not be considered limiting, and other equally effective examples are possible and contemplated. In addition, like reference numerals ("ref.") in the accompanying drawings ("Figures") indicate similar elements, and wherein:

[0006] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented;

[0007] Figure 1B is an example of an embodiment in which Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within the illustrated communication system;

[0008] Figure 1C is an example of an embodiment in which Figure 1A a system diagram of an example radio access network (RAN) and an example core network (CN) used within the illustrated communication system;

[0009] Figure 1D is an example of an embodiment in which Figure 1A A system diagram of another example RAN and another example CN used within the illustrated communication system;

[0010] Figure 2is a block diagram illustrating a WTRU having both a 3GPP access network and a non-3GPP access network in Release 15;

[0011] Figure 3 is a block diagram illustrating a WTRU having both a 3GPP access network and a non-3GPP access network in Release 16;

[0012] Figure 4 is a flow chart illustrating redundant boot mode operation according to one embodiment;

[0013] Figure 5 is a signaling diagram illustrating an enhanced packet data unit (PDU) session establishment for supporting redundant boot mode according to one embodiment;

[0014] Figure 6 is a signaling diagram illustrating WTRU notification of a state change to redundant booting mode;

[0015] Figure 7 is a flow chart illustrating an example process for use with a multi-access PDU session establishment and / or a multi-access PDU session modification;

[0016] Figure 8 is a flowchart illustrating an example process according to various embodiments;

[0017] Fig. 9 is a flowchart illustrating an example process according to various embodiments; and

[0018] Fig.10 is a flow chart illustrating an example process according to various embodiments. DETAILED DESCRIPTION

[0019] introduction

[0020] In the following detailed description, many specific details are set forth to provide a thorough understanding of the embodiments and / or examples disclosed herein. However, it should be understood that such embodiments and examples can be practiced without some or all of the specific details set forth herein. In other cases, well-known methods, processes, components and circuits are not described in detail to avoid blurring the following description. In addition, the embodiments and examples not specifically described herein can be practiced in place of the embodiments and other examples explicitly, implicitly and / or inherently described, disclosed or otherwise provided (collectively referred to as "provided") herein, or practiced in combination with these embodiments and examples. Although various embodiments are described and / or claimed herein, wherein devices, systems, equipment, etc. and / or any of their elements perform operations, processes, algorithms, functions, etc. and / or any part thereof, it should be understood that any embodiments described herein and / or protected by the claims assume that any device, system, equipment, etc. and / or any of its elements are configured to perform any operations, processes, algorithms, functions, etc. and / or any part thereof.

[0021] Example Communication System

[0022] Figure 1A 1 is a diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources (including wireless bandwidth). For example, the communication system 100 may employ one or more channel access methods such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word DFT spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0023] like Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, RAN 104 / 113, CN 106 / 115, public switched telephone network (PSTN) 108, Internet 110 and other networks 112, but it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a “station” and / or “STA”) may be configured to send and / or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smart phone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watch or other wearable device, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated process chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0024] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device that is configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a gNB, an NR Node B, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0025] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the base station 114b may be configured to send and / or receive wireless signals on one or more carrier frequencies (which may be referred to as cells (not shown)). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of licensed and unlicensed spectrums. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with the base station 114a may be divided into three sectors. Therefore, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In one embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to send and / or receive signals in a desired spatial direction.

[0026] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0027] More specifically, as noted above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 116. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink Packet Access (HSDPA) and / or High Speed ​​Uplink Packet Access (HSUPA).

[0028] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA) that may establish the air interface 116 using Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-A Pro).

[0029] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using New Radio (NR).

[0030] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may together implement LTE radio access and NR radio access, for example, using dual connectivity (DC) principles. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0031] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0032] Figure 1AThe base station 114b in the example may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business location, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology (such as IEEE 802.11) to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology (such as IEEE 802.15) to establish a wireless personal area network (WPAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a micro-micro cell base station or a femto cell base station. As Figure 1A As shown, base station 114b may have a direct connection to Internet 110. Therefore, base station 114b may not need to access Internet 110 via CN 106 / 115.

[0033] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network configured to provide voice, data, applications and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not described in detail in the accompanying drawings, the CN 106 / 115 may be used to provide a plurality of WTRUs 102a, 102b, 102c, 102d, and / or ... Figure 1A Although not shown in the figure, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0034] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired communication networks and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 / 113 or a different RAT.

[0035] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0036] Figure 1B is a system diagram illustrating an example WTRU 102. Figure 1B As shown, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0037] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal decoding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, but it is understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0038] The send / receive element 122 may be configured to send a signal to a base station (e.g., base station 114a) or receive a signal from the base station via an air interface 116. For example, in one embodiment, the send / receive element 122 may be an antenna configured to send and / or receive an RF signal. In one embodiment, the send / receive element 122 may be a transmitter / detector configured to send and / or receive, for example, an IR, UV or visible light signal. In another embodiment, the send / receive element 122 may be configured to send and / or receive both an RF signal and an optical signal. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0039] Although the transmit / receive element 122 Figure 1B 1 as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0040] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. For example, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11.

[0041] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from and store data in a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0042] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0043] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0044] The processor 118 may also be coupled to other peripherals 138, which may include one or more software modules and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. Peripheral device 138 may include one or more sensors, which may be one or more of the following: a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0045] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all signals (e.g., associated with specific subframes for both uplink (e.g., for transmission) and downlink (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit 139 for reducing and / or substantially eliminating self-interference via hardware (e.g., choke) or via signal processing performed by a processor (e.g., a separate processor (not shown) or via the processor 118). In one embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all signals (e.g., associated with specific subframes for both uplink (e.g., for transmission) or downlink (e.g., for reception)) may be concurrent and / or simultaneous.

[0046] Figure 1C 1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0047] The RAN 104 may include evolved Node-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of evolved Node-Bs while remaining consistent with an embodiment. The evolved Node-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the evolved Node-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the evolved Node-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0048] Each of the evolved Node Bs 160a, 160b, and 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, user scheduling in uplink (UL) and / or downlink (DL), etc. Figure 1C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0049] Figure 1C The illustrated CN 106 may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements is depicted as being part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0050] The MME 162 may be connected to each of the evolved Node-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0051] The SGW 164 may be connected to each of the evolved Node-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-evolved Node-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0052] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0053] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may be in communication with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers.

[0054] Although the WTRU Figures 1A to 1D Although described as wireless terminals, it is contemplated that in certain representative embodiments, such terminals may (eg, temporarily or permanently) use a wired communications interface with a communications network.

[0055] In a representative embodiment, the other network 112 may be a WLAN.

[0056] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for a BSS and one or more stations (STA) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or carries traffic away from the BSS. Traffic originating from outside the BSS and leading to the STA may be reached by the AP and may be delivered to the STA. Traffic originating from the STA and leading to a destination outside the BSS may be transmitted to the AP to be delivered to the corresponding destination. Traffic between STAs within the BSS may be transmitted by the AP, for example, wherein the source STA may transmit traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. Point-to-point traffic may be transmitted between the source STA and the destination STA (e.g., directly between them) using a direct link setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using an independent BSS (IBSS) mode may not have an AP, and STAs within or using the IBSS (eg, all STAs in the STA) may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0057] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may send beacons on a fixed channel (such as a primary channel). The primary channel may be a fixed width (e.g., a 20 MHz wide bandwidth) or a width dynamically set via signaling. The primary channel may be an operating channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. For CSMA / CA, a STA (e.g., each STA) (including the AP) may listen to the primary channel. If the primary channel is listened / detected and / or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0058] High throughput (HT) STAs may communicate using a 40 MHz wide channel, for example, via a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0059] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz wide channels. 40MHz channels and / or 80MHz channels can be formed by combining continuous 20MHz channels. 160MHz channels can be formed by combining 8 continuous 20MHz channels, or by combining two non-continuous 80MHz channels (this can be called 80+80 configuration). For 80+80 configuration, after channel coding, the data can pass through a segment parser that can divide the data into two streams. Each stream can be processed by inverse fast Fourier transform (IFFT) and time domain processing separately. These streams can be mapped to two 80MHz channels, and data can be sent by sending STA. At the receiver of the receiving STA, the above-mentioned operation for 80+80 configuration can be reversed, and the combined data can be transmitted to the medium access control (MAC).

[0060] 802.11af and 802.11ah support operating modes below 1GHz. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support instrument type control / machine type communications, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support for (e.g., only support for) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0061] WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA (which supports the minimum bandwidth operating mode) from all STAs operating in the BSS. In the example of 802.11ah, for STAs (e.g., MTC-type devices) that support (e.g., only support) a 1MHz mode, the primary channel may be 1MHz wide, even if the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because a STA (supporting only a 1MHz operating mode) is sending to the AP, the entire available frequency band may be considered busy even if most of the frequency bands remain idle and may be available.

[0062] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

[0063] Figure 1D 1 is a system diagram illustrating the RAN 113 and the CN 115 according to one embodiment. As noted above, the RAN 113 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0064] The RAN 113 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 180b may utilize beamforming to send signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to send wireless signals to and / or receive wireless signals from the WTRU 102a. In one embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In one embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and gNB 180b (and / or gNB 180c).

[0065] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with parameter sets that may be scalable. For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or Transmission Time Intervals (TTIs) of varying or scalable lengths (e.g., containing varying numbers of OFDM symbols and / or varying absolute time lengths over time).

[0066] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c while not accessing other RANs (e.g., such as the eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may use one or more of the gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with the gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNodeB 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNodeBs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNodeB 160a, 160b, 160c may act as a mobility anchor for the WTRUs 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0067] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in uplink (UL) and / or downlink (DL), support of network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards a user plane function (UPF) 184a, 184b, routing of control plane information towards an access and mobility management function (AMF) 182a, 182b, etc. As shown in FIG. Figure 1D As shown, gNBs 180a, 180b, and 180c may communicate with each other via an Xn interface.

[0068] Figure 1DThe illustrated CN 115 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possible data networks (DNs) 185a, 185b. Although each of the foregoing elements is depicted as part of the CN 115, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0069] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, support of network slicing (e.g., handling of different PDU sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of NAS signaling, mobility management, etc. The AMF 182a, 182b may use network slicing in order to customize CN support for the WTRU 102a, 102b, 102c based on the type of services utilized by the WTRU 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced mobile broadband (eMBB) access, services for machine type communication (MTC) access, etc. The AMF 182a, 182b may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0070] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 115 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 115 via the N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure traffic routing through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0071] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, etc.

[0072] The CN 115 may facilitate communications with other networks. For example, the CN 115 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b via the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and the N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0073] Given that Figures 1A to 1D as well as Figures 1A to 1D Corresponding to the description of the present invention, one or more or all of the functions described herein with reference to one or more of the following may be performed by one or more simulation devices (not shown): WTRU102a-102d, base station 114a-114b, evolved Node B 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMF 182a-182b, UPF 184a-184b, SMF 183a-183b, DN 185a-185b and / or any other device described herein. The simulation device may be one or more devices configured to mimic one or more or all of the functions described herein. For example, the simulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0074] The simulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, one or more simulation devices may perform one or more functions or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. One or more simulation devices may perform one or more functions or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device may be directly coupled to another device for testing purposes and / or may use over-the-air wireless communications to perform testing.

[0075] One or more simulation devices can perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, the simulation device can be used in a test scenario in a test lab and / or a non-deployed (e.g., testing) wired and / or wireless communication network to implement testing of one or more components. One or more simulation devices can be test equipment. Direct RF coupling and / or wireless communication via RF circuits (e.g., which can include one or more antennas) can be used by the simulation device to send and / or receive data.

[0076] Overview

[0077] This article discloses methods, devices, systems, etc. related to access traffic steering, switching and splitting (ATSSS) redundant traffic steering mode.

[0078] In various embodiments, a method for and / or used with an ASSS redundant traffic steering mode may be implemented in a WTRU and may include any of the following operations: sending first information to a first network element, the first information indicating a request to establish a multi-access protocol data unit (PDU) session or a request to modify a multi-access PDU session; receiving second information via a second network element, the second information indicating a response to the request to establish a multi-access PDU session or the request to modify the multi-access PDU session; determining first values ​​of multiple metrics of a first access network; determining second values ​​of the multiple metrics of a second access network; based on a rule for a redundant steering mode and the first and second values ​​of the multiple metrics satisfying corresponding conditions of the rule, determining to send a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network; and sending the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0079] In various embodiments, a method for and / or use with an ASSS redundant traffic steering mode may be implemented in a WTRU and may include any of the following operations: sending first information to a first network element, the first information indicating a request to establish a multi-access PDU session or a request to modify the multi-access PDU session; receiving second information via a second network element, the second information indicating a response to the request to establish a multi-access PDU session or the request to modify the multi-access PDU session; determining a first value of a plurality of metrics of a first access network; determining a second value of the plurality of metrics of a second access network; based on a rule for a redundant steering mode and the first value and the second value of the plurality of metrics satisfying corresponding conditions of the rule, determining to receive a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network; and receiving the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0080] In various embodiments, a method for and / or use with an ASSS redundant traffic steering mode may be implemented in a WTRU and may include any of the following operations: sending first information to a first network element, the first information indicating a request to establish a multi-access protocol data unit (PDU) session or a request to modify the multi-access PDU session; receiving second information via a second network element, the second information indicating a response to the request to establish the multi-access PDU session or the request to modify the multi-access PDU session; determining to send or receive a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network based on a rule for a redundant steering mode, a first value of a plurality of metrics of a first access network that satisfies a corresponding condition of the rule, and a second value of the plurality of metrics of a second access network that satisfies a corresponding condition of the rule; and performing one of sending the PDU and receiving the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0081] In various embodiments, a method for and / or use with ASSSS redundant traffic steering mode may be implemented in a WTRU and may include any of the following operations: sending first information to a first network element, the first information indicating one of a request to establish a multi-access PDU session or a request to modify a multi-access PDU session and one or more redundant steering mode capabilities of the WTRU; receiving second information via a second network element, the second information indicating a response to the request to establish a multi-access PDU session or a request to modify a multi-access PDU session and one or more redundant steering mode capabilities of the WTRU; Rules, including rules; based on one of the rules, first values ​​of multiple metrics of a first access network that meets the corresponding conditions of the rule, and second values ​​of the multiple metrics of a second access network that meets the corresponding conditions of the rule, determine to send or receive a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network; and perform one of sending the PDU and receiving the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0082] In various embodiments, an apparatus for and / or used with an ASSS redundant traffic steering mode may be configured to: receive third information via a second network element during a registration process, the third information indicating support for traffic steering; send first information to a first network element, the first information indicating a request to establish a multi-access PDU session or a request to modify the multi-access PDU session; receive second information via a second network element, the second information indicating a response to the request to establish a multi-access PDU session or the request to modify the multi-access PDU session; determine a first value of a plurality of metrics of a first access network; determine a second value of the plurality of metrics of a second access network; determine, based on a rule for a redundant steering mode and the first value and the second value of the plurality of metrics satisfying corresponding conditions of the rule, to send a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network; and / or send the PDU via the first access network, the second access network, or one of the first access network and the second access network.

[0083] In various embodiments, an apparatus for and / or used with an ASSS redundant traffic steering mode may be configured to: send first information to a first network element, the first information indicating a request to establish a multi-access protocol data unit (PDU) session or a request to modify a multi-access PDU session; receive second information via a second network element, the second information indicating a response to the request to establish a multi-access PDU session or the request to modify the multi-access PDU session; determine a first value of a plurality of metrics of a first access network; determine a second value of the plurality of metrics of a second access network; based on a rule for a redundant steering mode and the first value and the second value of the plurality of metrics satisfying corresponding conditions of the rule, determine to receive a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network; and receive the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0084] In various embodiments of the method and apparatus, the PDU is a PDU of the SDF associated with the multi-access PDU session. In various embodiments of the method and apparatus, based on the rule, the redundant boot mode is changed from inactive to active under the condition that only one of the first access network and the second access network cannot meet the requirements of the SDF. In various embodiments of the method and apparatus, based on the rule, the redundant boot mode is changed from active to inactive under the condition that only one of the first access network and the second access network can meet the requirements of the SDF.

[0085] In various embodiments of the method and apparatus, information indicating a duration of the state of the redundant boot mode is received from the network. In various embodiments of the method and apparatus, information indicating which of the first access network or the second access network is used is received for the duration. In various embodiments of the method and apparatus, measurements of either the first access network and the second access network that are removed are suspended for the duration. In various embodiments of the method and apparatus, the WTRU transitions to IDLE mode on the access network that is removed for the duration.

[0086] In various embodiments of the method and apparatus, wherein the first information indicates one or more redundant boot mode capabilities of the WTRU, and wherein the second information indicates one or more rules for redundant boot mode, including the rule.

[0087] In various embodiments of the method and apparatus, the plurality of metric network elements are access and mobility management functions. In various embodiments of the method and apparatus, the second network element is a base station. In various embodiments of the method and apparatus, the second network element is a base station associated with the first access network, the second access network, or a second one of the first access network and the second access network that is different from the first.

[0088] In various embodiments of the method and apparatus, the plurality of metrics includes any two of packet loss rate, delay, variability of delay, and load.

[0089] In various embodiments of the method and apparatus, the one or more rules for the redundant boot mode include information indicating that an initial state of the redundant boot mode is one of active and inactive. In various embodiments of the method and apparatus, an initial PDU of the SDF is sent via the first access network, the second access network, or the one of the first access network and the second access network based on the initial state of the redundant boot mode being one of active and inactive.

[0090] In various embodiments of the method and apparatus, the one or more rules include information indicating a measurement configuration for the plurality of metrics. In various embodiments of the apparatus, wherein the circuitry is configured to expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU. In various embodiments of the method, the method may include expecting to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0091] In various embodiments of the method, the method may receive third information via the second network element during a registration process, the third information indicating support for traffic steering. In various embodiments of the method, determining to send the PDU may include: determining to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the plurality of metrics satisfying the corresponding condition of the rule, and the rule indicating that PDU replication for the redundant steering mode is not active; and sending the PDU may include: sending the PDU based on the indicated PDU replication.

[0092] In various embodiments of the device, the circuit is configured to determine whether to send or receive a PDU, including: the circuit is configured to determine to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the multiple metrics that satisfy the corresponding conditions of the rule, and the rule indicating that PDU replication for the redundant boot mode is inactive; and the circuit is configured to send the PDU, including: the circuit is configured to send the PDU based on the indicated PDU replication.

[0093] In various embodiments, one of these methods may be implemented in a WTRU and may include any of the following operations: receiving first information from a network element during a registration process, the first information indicating support for traffic steering; sending second information to the first network element, the second information may indicate one or more redundant steering mode capabilities of the WTRU; receiving third information, for example, via the second network element, wherein the third information may indicate one or more rules for redundant steering mode; and sending a PDU associated with the multi-access PDU session via at least one of the first access network and the second access network, wherein: (i) the PDU is sent via the first access network and the second access network based on a first rule among the rules and a first value of two or more metrics associated with each of the first access network and the second access network, and (ii) the PDU is sent via one of the first access network and the second access network based on a second rule among the rules and a second value of two or more metrics associated with each of the first access network and the second access network.

[0094] In various embodiments, the first network element may be, for example, an AMF. In various embodiments, the first information may be or include a multiple access PDU session support indicator.

[0095] In various embodiments, the redundant boot mode capability of the WTRU may be or include ATSSS capability. In various embodiments, the ATSSS capability (the redundant boot mode capability) may include any one of support for redundant traffic boot mode, support for duplicate detection, and support for specific boot functionality. In various embodiments, the second information may indicate one of a request to establish a multi-access protocol PDU session or a request to modify a multi-access PDU session. As an example, the second information may be a PDU session establishment request or a PDU session modification request, the PDU session establishment request or the PDU session modification request having information about the redundant boot mode capability of the WTRU.

[0096] In various embodiments, the third information may indicate a response to the request to establish a multi-access PDU session or the request to modify a multi-access PDU. As an example, the third information may be a PDU session establishment request accept message having information about (e.g., indicating) at least one of the ATSSS rule for redundant boot mode and other rules for redundant boot mode. In various embodiments, the WTRU may expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0097] In various embodiments, at least one of the one or more rules indicates that PDU duplication for the redundant boot mode is inactive (or active), and the WTRU may be configured to send the PDU based on the indicated PDU duplication based on the absence of any value for one or more of the metrics associated with each of the first access network and the second access network. In various embodiments, the first rule may indicate that the first access network and the second access network are used under the following conditions: (i) first values ​​of two or more metrics associated with the first access network and (ii) first values ​​of two or more metrics associated with the second access network do not satisfy corresponding thresholds.

[0098] In various embodiments, one of these methods may be implemented in a WTRU and may include any of the following operations: sending a packet data unit (PDU) session establishment request by the WTRU, the packet data unit (PDU) session establishment request having information about the redundant boot mode capability of the WTRU; receiving a PDU session establishment request accept message by the WTRU, the PDU session establishment request accept message having information about (e.g., indicating) an ATSSS rule for redundant boot mode and at least one of other rules for redundant boot mode; sending one or more PDUs in redundant boot mode according to the ASSSS rule or at least one of these other rules.

[0099] In various embodiments, sending the one or more PDUs may include switching between an active state and an inactive state of the redundant boot mode based on one or more trigger conditions. Alternatively, the method may include any of the following operations: switching between an active state and an inactive state of the redundant boot mode based on one or more trigger conditions; and sending the one or more PDUs based on an active state or an inactive state caused by the switching (e.g., each of one or more instances of the switching).

[0100] In various embodiments, sending the one or more PDUs may include monitoring the one or more trigger conditions for a transition from an active redundant boot mode to an inactive redundant boot mode based on one or more performance metrics. Alternatively, the method may include any of the following operations: monitoring the one or more trigger conditions for a transition from an active redundant boot mode to an inactive redundant boot mode based on one or more performance metrics; and in response to detecting (determining) the transition and the active state before the transition or detecting (determining) the transition, sending the one or more PDUs based on the inactive state.

[0101] In various embodiments, the method may include: receiving, by the WTRU from a user plane function (UPF), an indication for triggering a state transition of a redundant boot mode; and switching between an active state and an inactive state of the redundant boot mode in response to the received indication.

[0102] In various embodiments, the method may include determining, by the WTRU, a trigger condition for a state transition to a redundant booting mode based on a mobility event.

[0103] In various embodiments, the method may include any of the following operations: receiving, by the WTRU, a signal from a performance management function (PMF) for the WTRU to notify the UPF of a state change of a redundant boot mode; and notifying the UPF of the state change of the redundant boot mode in response to the signal by the WTRU.

[0104] In various embodiments, the WTRU is one of these devices, which includes a transmitter, a receiver, a processor and a memory, and the WTRU is configured to perform a method according to at least one of the various embodiments disclosed above (and below).

[0105] Representative methods and apparatus for access traffic steering, switching and splitting (ATSSS) redundant traffic steering mode

[0106] Representative ATSSS in 3GPP

[0107] Most WTRUs are capable of both 3GPP access and non-3GPP access. This capability provides flexibility to network operators in determining which access networks to use for service data flows (SDFs). Figure 2As shown in , a UE 200 using both a 3GPP access network and a non-3GPP access network needs to establish independent single access PDU sessions 202A and 202B through the 3GPP access network and the non-3GPP access network, respectively. The term "packet data unit" and its abbreviation "PDU" may be used interchangeably with the term "protocol data unit" (e.g., according to the Third Generation Partnership Project ("3GPP"); Technical Specification Group Services and System Aspects; System Architecture for 5G System (5GS); Stage 2, (Release 17), 3GPP TS 23.501 v17.3.0.).

[0108] However, it is clear that such an architecture does not fully exploit the flexibility. In version 16, and as Figure 3 As shown in , the concept of a multi-access PDU session 302 is introduced, thereby allowing the uplink traffic and downlink traffic of the SDF to be more easily directed, switched or diverted between the 3GPP access network and the non-3GPP access network. As used herein, a multi-access PDU session is a PDU session in which traffic can be transmitted through one access network, some access networks or all access networks in multiple access networks. For example, traffic of the multi-access PDU session 302 can be sent through a first access network of two access networks (e.g., a 3GPP access network), through a second access network of the two access networks (e.g., a non-3GPP access network), or through two access networks of the two access networks (e.g., a 3GPP access network and a non-3GPP access network).

[0109] The new architecture introduced in Release 16 is further enhanced in Release 17 and allows the following “steering functionalities”: (i) access traffic steering; (ii) access traffic switching; and (iii) access traffic splitting.

[0110] Access traffic steering functionality is the process by which (i) an access network is selected for a new data flow and (ii) traffic for the data flow is delivered over the selected access network. Access traffic steering is applicable between 3GPP access networks and non-3GPP access networks.

[0111] Access traffic switching functionality is the process by which all traffic of an ongoing data flow is moved from one access network to another in a manner that maintains the continuity of the data flow. Access traffic offloading is applicable between 3GPP access networks and non-3GPP access networks.

[0112] Access traffic offloading functionality is the process by which traffic of a data flow is offloaded across multiple access networks. Access traffic offloading is applicable between 3GPP access networks and non-3GPP access networks. When traffic offloading is applied to a data flow, some traffic of the data flow is delivered via one access network and some other traffic of the same data flow is delivered via another access network. Access traffic offloading is applicable between 3GPP access networks and non-3GPP access networks.

[0113] The steering functionality in an ATSSS-capable WTRU can steer, switch and / or divert traffic for a multi-access PDU session across 3GPP access networks and non-3GPP access networks. Two types of steering functionality have been standardized. The first is a high-level steering functionality that operates above the IP layer. In Release 17, only one high-level steering functionality is specified, which applies the Multipath TCP (MPTCP) protocol (IETF RFC 8684) and is called "MPTCP functionality". This functionality is only applicable to TCP traffic. The second is a low-level steering functionality that operates below the IP layer. In Release 17, only one type of low-level steering functionality is defined and is called "ATSSS low-level functionality" or "ATSSS-LL functionality". The ATSSS-LL functionality is applicable to Ethernet and IP (i.e., TCP and UDP). The steering functionality (e.g., either of the MPTCP functionality and the ATSSS-LL functionality) is a new functionality that exists in both the WTRU and the UPF (i.e., in the endpoints of the PDU session).

[0114] For each steering functionality, one or more steering modes are supported. The steering mode determines how traffic matching the SDF should be distributed across 3GPP access networks and non-3GPP access networks. As of Release 16, supported steering modes include: (i) active standby steering mode; (ii) minimum delay steering mode; (iii) load balancing steering mode; and (iv) priority-based steering mode.

[0115] The active-standby steering mode is used to steer traffic to one access network (active access network) when the access network is available, and switch to steering traffic to another access network (standby access network) when the one (active) access network becomes unavailable.

[0116] Minimum Delay Steering Mode is used to steer traffic to the access network determined to have the minimum round trip time (RTT). The WTRU and UPF measure their respective RTTs to determine which access network has the minimum RTT. According to 3GPP specifications as of Release 16, Minimum Delay Steering Mode is only available for Non-Guaranteed Bit Rate (Non-GBR) SDFs.

[0117] Load balancing directed mode is used to split traffic across the 3GPP access network and the non-3GPP access network according to the percentage of traffic that should be transmitted over the two access networks. According to 3GPP specifications as of Release 16, load balancing directed mode is applicable only to non-GBR SDF.

[0118] Priority-based steering mode is used to steer all traffic matching the rules issued by the Policy Charging Control (PCC) network element onto the high-priority access network until it is determined that the access network is congested. After the high-priority access network is determined to be congested, some traffic is also transferred to the low-priority access network, i.e., traffic is split across the two access networks. According to 3GPP specifications as of Release 16, priority-based steering mode can only be used for non-GBR SDF.

[0119] Active standby steering mode, minimum delay steering mode, load balancing steering mode, and priority-based steering mode are enhanced in Release 17. For load balancing steering mode, 3GPP adds a steering mode indicator. The steering mode indicator indicates that the WTRU may change the default steering parameters in the steering mode percentage provided by the network and may adjust the traffic steering based on its own decision. Only one of the following steering mode indicators may be provided: (i) autonomous load balancing indicator and (ii) UE assisted indicator.

[0120] When the autonomous load balancing indicator is provided to the WTRU, the WTRU may ignore the percentage in the guided mode component (i.e., the default percentage provided by the network) and may autonomously determine its own percentage for traffic splitting in a manner that maximizes the aggregate bandwidth in the uplink direction. When the UE Assistance Indicator is provided to the WTRU by the network, the UE Assistance Indicator indicates to the WTRU that: (a) the WTRU may decide how to allocate uplink traffic matching the SDF based on the WTRU's internal state (e.g., when the WTRU is in a special internal state, such as a low battery), and (b) the WTRU may notify the corresponding UPF of its decision on how to allocate uplink traffic matching the SDF. In the event that the WTRU is not in a special internal state, the WTRU will allocate uplink traffic as instructed by the network even if the UE Assistance Indicator is provided by the network.

[0121] In addition, for the load balancing steering mode, 3GPP introduces thresholds for the WTRU and UPF to be applied to measurements made for (or in conjunction with) the load balancing steering mode. The threshold for each access network can be the value of the RTT measurement or the value of the packet loss rate (PLR) measurement. When at least one measured parameter (i.e., RTT or PLR) on an access network exceeds the threshold (provided to the WTRU and UPF), the WTRU and UPF may stop transmitting traffic on the access network, or may continue to transmit traffic on the access network but the traffic on the access network should be reduced by a specific implementation amount and the reduced amount of traffic should be transmitted on the other access network. When all measured parameters (i.e., RTT and PLR) of both access networks do not exceed the provided thresholds, the WTRU and UPF will apply a fixed diversion percentage.

[0122] For priority-based steering mode, 3GPP also introduces thresholds for the WTRU and UPF to be applied to measurements made for (or in conjunction with) priority-based steering mode. The threshold for each access network can be a value for RTT measurement or a value for PLR measurement. The WTRU and UPF should consider these thresholds to determine when an access network becomes congested. For example, when a parameter (i.e., RTT or PLR) measured on a high priority access network exceeds a threshold (provided to the WTRU and UPF), the WTRU and UPF may consider the high priority access network to be in a congested state and also transfer the traffic to a low priority access network.

[0123] To enable the bootstrap mode for each of these bootstrap functionalities, some rules are required at both the WTRU and the UPF. These rules are generated by the SMF based on information known to the Policy Control Function (PCF) and are communicated to the WTRU (ATSSS rules) to determine the handover functionality and handover mode for uplink traffic and to the UPF (N4 rules) to determine the handover functionality and handover mode for downlink traffic.

[0124] Furthermore, to support some bootstrapping modes, a performance management function (PMF) protocol is required at the WTRU and UPF to perform the measurements necessary for handover mode decisions (RTT measurements, access availability / unavailability reporting, PLR measurements).

[0125] The 3GPP Technical Specification Group Services and System Aspects (TSG SA) Working Group 1 (SA1) in 3GPP; the business requirements for 5G systems in 3GPP TS 22.261 V18.5.0 have described many vertical markets and applications where 5G systems are expected to provide data delivery capabilities with strict performance requirements in terms of very low latency and high reliability. These use cases are generally referred to as requiring URLLC. Solutions for URLLC use cases have been addressed both on the access network side (e.g., preemption) and on the core network side (session and service continuity (SSC) mode, end-to-end redundant user plane paths based on dual connectivity). However, these solutions fail to consider the potential redundancy of multi-access PDU sessions.

[0126] One of the issues addressed by the various disclosed embodiments is how and when to use redundant boot mode.

[0127] In both cases (ie, static redundant boot mode and dynamic redundant boot mode), the legacy PDU session establishment process does not support the new boot mode.

[0128] New criteria and / or triggers for dynamic guidance mode are disclosed below, including new criteria and / or triggers for both WTRU and UPF to determine when to activate or deactivate guidance mode. These criteria and / or trigger conditions can be based on existing measurements as well as new measurements customized for URLLC use cases.

[0129] The features, methods and techniques disclosed herein include: (1) an enhanced PDU session establishment process, including ATSSS capabilities for redundant boot mode and / or ATSSS rules and WTRU rules for redundant boot mode; (2) a redundant boot mode that can be converted / switched between an active state and an inactive state based on a trigger condition; (3) a trigger condition for transitioning the redundant boot mode from active to inactive based on performance metric monitoring; (4) a trigger condition for transitioning the redundant boot mode from inactive to active based on performance metric monitoring; (5) receiving an indication of a state transition of a redundant boot mode from a UPF at a WTRU; (6) determining a trigger condition for a state transition of a redundant boot mode based on a mobility event at a WTRU; and (7) a PMF signaling exchange for the WTRU to notify the UPF of the state change of the redundant boot mode.

[0130] Representative overall operation

[0131] In the following, the term "service data flow" or its abbreviation "SDF" is used to describe traffic from an application that may or may be affected by a steering mode. A service data flow may be identified by an IP 5-tuple, by a specific application ID, or by any identifier that may identify a flow of an application. The terms "access network" and "access networks" may be used interchangeably with the terms "access network" and "access networks" (e.g., respectively), and the use of the term "network" in the terms "access network" and "access networks" does not mean that either of the "access network" and / or "access networks" necessarily includes more than one network element.

[0132] The WTRU and the UPF may be configured with multiple access PDU sessions, and the WTRU and the UPF may send PDUs via 3GPP paths and / or non-3GPP paths. In the following, the term "access path" may be used interchangeably with "access branch".

[0133] The redundant bootstrap mode allows PDUs to be replicated and sent through two (or more) access networks (e.g., a 3GPP access network and a non-3GPP access network). In the following, the terms "static redundant bootstrap mode" and the term "static replication" are used interchangeably and should be understood as a less dynamically changing bootstrap mode. It is generally expected that the bootstrap mode is fixed for the duration of the SDF. All PDUs of the SDF may be affected by the bootstrap mode and sent through two (or more) access networks (e.g., a 3GPP access network and a non-3GPP access network). Static replication means that all PDUs of the SDF will be replicated through these two (or more) access networks.

[0134] In the following, the term "latency requirement" and the term "delay requirement" are used interchangeably.

[0135] Hereinafter, the term "dynamic redundant boot mode" and the term "dynamic replication" are used interchangeably and should be understood as a non-static boot mode. The dynamic redundant boot mode may have two (or more) states, and may be in only one of the two (or more) states at any time. The first state may be an active state (where replication occurs) and the second state may be an inactive state (where replication does not exist). The dynamic redundant boot mode may undergo a state change from an active state to an inactive state, and / or a change from an inactive state to an active state. Although being triggered to be in or transitioning to a new state (e.g., one of an active state or an inactive state) or transitioning to a new state may be considered as other states of the dynamic redundant boot mode. However, in order to simplify the description herein, the dynamic redundant boot mode is considered to remain in the current state (e.g., active or inactive) until a transition to a new state (e.g., the opposite state of the current state) has been completed.

[0136] In the active state, the PDUs of the SDF may be sent through two (or more) access networks (e.g., a 3GPP access network and a non-3GPP access network). In the inactive state, another bootstrap mode (such as an active standby mode) may be used to send the PDUs of the SDF only through a single access network (e.g., one of a 3GPP access network or a non-3GPP access network). During the active state, the WTRU and the UPF may monitor a trigger set (e.g., a first trigger set ("trigger set 1")) to determine whether to continue sending through two (or more) access networks (i.e., remain in the active state) or to send the PDUs only through a single access network (i.e., transition to the inactive state). During the inactive state, the WTRU and the UPF may monitor a trigger set (e.g., a second trigger set ("trigger set 2")) to determine whether to continue sending through a single access network (i.e., remain in the inactive state) or to send the PDUs through two (or more) access networks (i.e., transition to the active state). Each of these trigger sets represents a group or set of trigger conditions that the WTRU and the UPF may monitor to make a state change (e.g., whether to transition) decision. Dynamic replication means that only the PDUs selected by the SDF will be replicated across the two access networks. These PDUs are selected based on trigger conditions, which are also called replication criteria. In the active state, the WTRU and UPF have used replication criteria to determine that the PDUs should be replicated across the two (or more) access networks. In the inactive state, the WTRU and UPF have used replication criteria to determine that the PDUs should not be replicated across the two (or more) access networks. In the inactive state, the replication criteria may also determine which access network (3GPP or non-3GPP) is used.

[0137] A WTRU and 5GC network with ATSSS capability may be able to apply the following procedure. The WTRU may determine whether the network supports ASSSS based on the Multi-Access PDU Session Support Indicator, which may be provided by the AMF during the registration process, for example, as specified in clause 4.22.9.1 of 3GPP; Technical Specification Group Services and System Aspects; Procedures for 5G System (5GS); Phase 2, (Release 17), 3GPP 23.502v17.3.0. If both the WTRU and 5GC are ATSSS capable, the network may decide to enable or disable redundant bootstrap mode. If redundant bootstrap mode is enabled, the network may further decide whether to adopt static replication or dynamic replication.

[0138] Figure 4 is a flow chart illustrating redundant boot mode operation according to various embodiments. Figure 4The redundant boot mode operation shown in may be adapted as a process at the WTRU and UPF for redundant boot mode. Of note in this process are: 1) reference to an enhanced PDU session establishment process; 2) rules for configuring various options for (e.g., static vs. dynamic) redundant boot mode; 3) different states for dynamic redundant boot mode (e.g., active and inactive); and 4) new monitoring and triggering events for moving from different states of dynamic redundant boot mode.

[0139] Reference Figure 4 , the WTRU may perform an enhanced PDU session establishment procedure (400) as described below with reference to Figure 5 As further described in detail. The WTRU may configure measurements to support redundant steering mode (408), and may generate, receive and / or determine uplink data to be sent at the WTRU (410). The WTRU may determine whether the uplink data matches an SDF subject to redundant steering mode (412), and if not, traffic steering may be abandoned and the uplink data may be sent (no steering applied). If the WTRU determines that the uplink data matches an SDF subject to redundant steering mode (412), the WTRU may determine whether to perform static redundant steering or dynamic redundant steering (402A) according to a rule. If the WTRU determines to perform static redundant steering (402A) according to a rule (e.g., required by a rule), the WTRU may transmit one or more PDUs of uplink data through two (or more) access networks. Alternatively, if the WTRU determines to perform dynamic redundant steering (402A) according to a rule (e.g., required by a rule), the WTRU may determine whether the dynamic redundant steering mode is active (402B) according to the rule.

[0140] If the WTRU determines that the dynamic redundant boot is in the active state (402B), the WTRU may monitor the first trigger set (406A) and may determine whether to change to the inactive state (416A). If the WTRU determines not to change state (416A), the WTRU may send one or more PDUs of uplink data (404A) through two (or more) access networks, and the process may return to (410). If the WTRU determines to change state (416A), the WTRU may send one or more PDUs of uplink data (404B) through the selected access network, and the process may return to (410).

[0141] If the WTRU determines that redundant booting is not in an active state (402B), the WTRU may monitor a second trigger set (406B) and may determine whether to change to an active state (416B). If the WTRU determines not to change state (416B), the WTRU may transmit one or more PDUs of uplink data over the selected access network (404B), and the process may return to (410). If the WTRU determines to change state (416B), the WTRU may send one or more PDUs of uplink data over two (or more) access networks (404B), and the process may return to (410).

[0142] Figure 4 The descriptions above and the accompanying descriptions apply to the case where the state change of the redundant boot mode occurs (e.g., by the WTRU) at a PDU transmission timing. Alternatively, the state transition may also occur at a non-PDU transmission timing. For example, the WTRU may continuously, constantly, or repeatedly monitor the trigger set (or replication criteria), and when one or more trigger conditions are met, the state of the dynamic redundant boot mode may be changed from replication to non-replication, or vice versa.

[0143] Enhanced representative PDU session establishment for redundant boot mode

[0144] During the establishment of a multi-access PDU session (see Figure 4 , at (400), the WTRU may send a PDU session establishment request to the AMF through an access network (e.g., a 3GPP access network or a non-3GPP access network). In a network that does not support ATSSS, the WTRU may not be allowed to initiate: (i) a process to establish a multi-access PDU session; (ii) a process to establish a PDU session with a "Multi-access PDU Network Upgrade Allowed" indication; (iii) a process to add user plane resources through one access network to an existing multi-access PDU session established through another access network in a different mobile network; or (iv) a process to perform a PDU session modification using a request type "Multi-access PDU Request" or using a "Multi-access PDU Network Upgrade Allowed" indication after moving from an Evolved Packet Core (EPC) to a 5GC.

[0145] Figure 5 is a signaling diagram illustrating an example enhanced PDU session establishment supporting redundant bootstrap mode according to one or more embodiments. Figure 5 At least some of the enhanced PDU session establishment shown in may be adapted to perform Figure 4 Enhanced PDU session establishment process (400) of the present invention. The exchange of the ATSSS capability of the redundant traffic steering mode and the ASSSS rules of the redundant traffic steering mode can be applied to the PDU session modification process.

[0146] Reference Figure 5 , the WTRU may send information related to establishing a PDU session ("PDU session establishment information") to the network (AMF and SMF) (501). The PDU session establishment information may include information indicating a request for establishing a PDU session ("PDU session establishment request information") and information indicating the ATSSS capability of the WTRU for redundant traffic steering. In various embodiments, the PDU session establishment information may be, for example, a PDU session establishment request message, which includes information indicating the ATSSS capability of the WTRU for redundant traffic steering. The WTRU may generate a PDU session establishment request message (e.g., according to a particular protocol) and may include the ATSSS capability of the WTRU for redundant traffic steering in such a message. As part of the PDU session establishment, the WTRU provides the ASSSS capability to the AMF. To enable redundant traffic steering modes, the WTRU may include one or more of the following information as part of the capability: (i) information indicating support for one or more redundant traffic steering modes; (ii) information indicating support for static redundant traffic steering modes; (iii) information indicating support for dynamic redundant traffic steering modes; (iv) information indicating support for redundant traffic steering modes via MPTCP; (v) information indicating support for redundant traffic steering modes via ATSSS-LL; and (vi) information indicating support for duplicate detection.

[0147] The information indicating support for the redundant traffic steering mode may be an indication of whether the WTRU supports the redundant traffic steering mode.

[0148] The information indicating support for the static redundant traffic steering mode may be an indication of whether the WTRU supports the static redundant traffic steering mode (e.g., the indication provided is one of a first indication that the WTRU supports the static redundant traffic steering mode and a second indication that the WTRU does not support the static redundant traffic steering mode). Alternatively, the information indicating support for the static redundant traffic steering mode may be an indication that the WTRU supports the static redundant traffic steering mode (e.g., the indication is provided if the WTRU supports the static redundant traffic steering mode, and the indication is not provided if the WTRU does not support the static redundant traffic steering mode). Implicit in the WTRU supporting the static redundant traffic steering mode is that the WTRU supports the redundant traffic steering mode. The information indicating support for the static redundant traffic steering mode may be provided in addition to, in lieu of, only when, and / or independently of providing information indicating support for the redundant traffic steering mode.

[0149] The information indicating support for the dynamic redundant traffic steering mode may be an indication of whether the WTRU supports the dynamic redundant traffic steering mode (e.g., the indication provided is one of a first indication that the WTRU supports the dynamic redundant traffic steering mode and a second indication that the WTRU does not support the dynamic redundant traffic steering mode). Alternatively, the information indicating support for the dynamic redundant traffic steering mode may be an indication that the WTRU supports the dynamic redundant traffic steering mode (e.g., the indication is provided if the WTRU supports the dynamic redundant traffic steering mode, and the indication is not provided if the WTRU does not support the dynamic redundant traffic steering mode). Implicit in the WTRU supporting the dynamic redundant traffic steering mode is that the WTRU supports the redundant traffic steering mode. The information indicating support for the dynamic redundant traffic steering mode may be provided as a supplement to, in lieu of, only when, and / or independently of providing information indicating support for the redundant traffic steering mode.

[0150] The information indicating support for the redundant traffic steering mode over MPTCP may be an indication of whether the WTRU supports the redundant traffic steering mode over MPTCP (e.g., the indication provided is one of a first indication that the WTRU supports the redundant traffic steering mode over MPTCP and a second indication that the WTRU does not support the redundant traffic steering mode over MPTCP). Alternatively, the information indicating support for the redundant traffic steering mode over MPTCP may be an indication that the WTRU supports the redundant traffic steering mode over MPTCP (e.g., the indication is provided if the WTRU supports steering functionality over MPTCP, and the indication is not provided if the WTRU does not support the redundant traffic steering mode over MPTCP). Implicit in the WTRU supporting the redundant traffic steering mode over MPTCP is that the WTRU supports the redundant traffic steering mode. The information indicating support for the redundant traffic steering mode over MPTCP may be provided in addition to, in lieu of, only when, and / or independently of providing information indicating support for the redundant traffic steering mode.

[0151] The information indicating support for the redundant traffic steering mode through ATSSS-LL may be an indication of whether the WTRU supports the redundant traffic steering mode through ATSSS-LL (e.g., the indication provided is one of a first indication that the WTRU supports the redundant traffic steering mode through ATSSS-LL and a second indication that the WTRU does not support the redundant traffic steering mode through ATSSS-LL). Alternatively, the information indicating support for the redundant traffic steering mode through ATSSS-LL may be an indication that the WTRU supports the redundant traffic steering mode through ATSSS-LL (e.g., the indication is provided if the WTRU supports the steering functionality through ATSSS-LL, and the indication is not provided if the WTRU does not support the redundant traffic steering mode through ATSSS-LL). Implicit in the WTRU supporting the redundant traffic steering mode through ASSSS-LL is that the WTRU supports the redundant traffic steering mode. Information indicating support for a redundant traffic steering mode through ATSSS-LL may be provided in addition to, as a substitute for, only when and / or independently of providing information indicating support for a redundant traffic steering mode.

[0152] The information indicating support for duplicate detection may be an indication of whether the WTRU supports duplicate detection and discard functionality (e.g., the indication provided is one of a first indication that the WTRU supports duplicate detection and discard functionality and a second indication that the WTRU does not support duplicate detection and discard functionality). Alternatively, the information indicating support for duplicate detection and discard functionality may be an indication that the WTRU supports duplicate detection and discard functionality (e.g., the indication is provided if the WTRU supports duplicate detection and discard functionality, and the indication is not provided if the WTRU does not support duplicate detection and discard functionality). The information indicating support for duplicate detection and discard functionality may be provided in addition to, instead of, only when, and / or independently of the information indicating support for redundant traffic steering mode through ATSSS-LL. Information indicating support for duplicate detection and discarding functionality may be provided in addition to, as a replacement for, only when, and / or independently of providing information indicating support for redundant traffic steering mode.

[0153] Although not shown, support for redundant traffic steering mode may be indicated by any number of steering functionalities.

[0154] The SMF may interact with the PCF to obtain PCC rules for redundant boot mode (e.g., based on ATSSS capabilities) (502-503). The SMF may determine ATSSS rules for redundant boot mode, N4 rules for redundant boot mode, and any measurement assistance information for redundant boot (504) (e.g., based on PCC rules for redundant boot mode). The ATSSS rules and N4 rules may include and / or indicate information specific to (belonging to) redundant boot mode. Information specific to (or belonging to) the redundant steering mode may include, for example, and belonging to the following information: (i) an identifier of the SDF ("SDF identifier"); (ii) a priority of the redundant steering mode; (iii) information indicating whether the redundant steering mode is applied to the uplink, the downlink, or both the uplink and the downlink; (iv) information indicating whether the redundant steering mode is or should be a static redundant steering mode or a dynamic redundant steering mode; (v) information indicating that the initial state or main state of the dynamic steering mode is or should be active or inactive; (vi) information indicating that if the dynamic steering mode is in the inactive state, the access network (e.g., 3GPP access network or non-3GPP access network) initial PDU transmission of the SDF is or should be an end state; (vii) information indicating whether performing duplicate detection and discarding is (or is) required for ASSSS-LL steering functionality; (viii) information indicating a default or fallback steering mode used when traffic duplication is not required (e.g., in a scenario where both 3GPP branches and non-3GPP branches can be used to meet the requirements of the SDF); and (ix) information indicating a measurement configuration that supports the redundant steering mode.

[0155] In various embodiments, the information indicating the measurement configuration supporting the redundant boot mode may include configuration details for the PMF, thresholds for triggering redundant boot mode state transitions, configuration details for new performance metrics, and the like.

[0156] In some cases, the redundancy bootstrap mode for the WTRU to UPF portion of the uplink path ("WTRU to UPF path") may be different from the UPF to WTRU portion of the downlink path ("UPF to WTRU path"). This may occur when the 3GPP leg uses frequency division duplexing and the uplink and downlink are on different spectrums. In this case, the performance metrics of the 3GPP leg may be different for the uplink and downlink, and therefore the replication state may not necessarily be the same for uplink transmissions and downlink transmissions. To account for this, the ATSSS rule and the N4 rule may have separate information for uplink and downlink.

[0157] Although not shown, the SMF may check with the Unified Data Manager (UDM) to determine whether the subscription allows redundant bootstrap mode, or, for example, whether redundant bootstrap mode is allowed in a home routing scenario. The SMF may assign QoS profiles to access networks. In Release 17, for GBR QoS flows, the SMF provides a QoS profile to a single access network. In the event that PCC rules allow GBR QoS flows in both access networks, the SMF decides which access network provides the QoS profile for the GBR QoS flow based on its local policy. When redundant bootstrap mode is supported for a GBR QoS flow, the SMF may provide QoS profiles to both access networks.

[0158] The SMF may send information related to establishing and / or modifying an N4 session ("N4 session establishment / modification information") to the UPF (505). The N4 session establishment / modification information may include information indicating a request for establishing / modifying an N4 session ("N4 session establishment / modification request information") and information indicating N4 rules and measurement assistance information. In various embodiments, the N4 session establishment information may be, for example, an N4 session establishment / modification request message including information indicating N4 rules and measurement assistance information. The SMF may generate an N4 session establishment / modification request message (e.g., according to a specific protocol) and may include information indicating N4 rules and measurement assistance information in such a message.

[0159] The UPF may receive N4 session establishment modification information (505), and may determine and / or configure N4 rules based on information indicating the N4 rules. The UPF may enable or disable redundant boot mode based on the N4 session establishment modification information (e.g., the N4 rules determined from the N4 session establishment modification information). For example, if redundant boot mode is enabled, the UPF may apply one or more of the N4 rules. For example, the UPF may apply one or more of the N4 rules to determine the details of the redundant boot mode. As an example, the UPF may determine that the replication may be one of static and dynamic based on a first rule in the N4 rules (e.g., specifying that the replication is static or dynamic). If determined to be dynamic, the UPF may determine that the initial state of the replication may be one of active and inactive based on a second rule in the N4 rules (e.g., specifying that the replication state is initially active or initially inactive). If it is determined to be inactive, the UPF may determine whether the main branch and / or the initial branch is one of a 3GPP branch and a non-3GPP branch based on a third rule in the N4 rule (e.g., specifying that the main branch and / or the initial branch is a 3GPP branch or a non-3GPP branch).

[0160] The UPF may send N4 session establishment / modification information to the SMF (506). The N4 session establishment / modification information may include information indicating a response to the N4 session establishment / modification request information ("N4 session establishment / modification response information"). In various embodiments, the N4 session establishment / modification information may be, for example, an N4 session establishment / modification response message. The SMF may generate the N4 session establishment / modification response message (e.g., according to a specific protocol).

[0161] The SMF may receive N4 session establishment / modification information from the UPF (506). The SMF may send PDU session establishment information to the WTRU (507). The PDU session establishment information may include information indicating acceptance of the PDU session establishment ("PDU session establishment acceptance information") and information indicating ATSSS rules and measurement assistance information. In various embodiments, the PDU session establishment information may be, for example, a PDU session establishment acceptance message, which includes information indicating ATSSS rules and measurement assistance information. The SMF may generate a PDU session establishment acceptance message (e.g., according to a particular protocol) and may include information indicating ATSSS rules and measurement assistance information in such a message.

[0162] The WTRU may receive PDU session establishment information (507) from the SMF, and may determine and / or configure the ATSSS rules based on the information indicating the ATSSS rules. The WTRU may enable or disable the redundant boot mode based on the PDU session establishment information (e.g., the ATSSS rules determined from the PDU session establishment acceptance information). For example, if the redundant boot mode is enabled, the WTRU may apply one or more rules in the ATSSS rules. For example, the WTRU may apply one or more rules in the ATSSS rules to determine the details of the redundant boot mode. As an example, the WTRU may determine that the replication may be one of static and dynamic based on a first rule in the ATSSS rules (e.g., specifying whether the replication is static or dynamic). If it is determined to be dynamic, the WTRU may determine that the initial state of the replication may be one of active and inactive based on a second rule in the ATSSS rules (e.g., specifying that the replication state is initially active or initially inactive). If it is determined to be inactive, the WTRU may determine whether the main branch and / or the initial branch is one of a 3GPP branch and a non-3GPP branch based on a third rule in the ATSSS rule (e.g., specifying that the main branch and / or the initial branch is a 3GPP branch or a non-3GPP branch).

[0163] During normal operation, the WTRU and UPF may follow the configured ATSSS rules and N4 rules, respectively. If the redundant bootstrap mode is enabled and dynamic, the WTRU and UPF may monitor triggers (based on measurements or events) to determine the duplication status. If the ATSSS rules (or N4 rules) specify that the WTRU (or UPF) does not need to perform duplicate detection and discard, the WTRU (or UPF) assumes that this functionality will be handled by higher layers (e.g., applications).

[0164] Representative dynamic redundant boot mode

[0165] When redundant boot mode is enabled, dynamic redundant boot mode may occur. The WTRU and UPF may use replication criteria to determine whether a replication is active or inactive. To enable dynamic switching between active and inactive, the WTRU and UPF may require and / or use performance measurements for each access network. For example, based on Figure 4 , at (408) and the accompanying disclosure, these measurements may be configured. The WTRU and UPF may make one or more of the following measurements: (i) one or more PLR ​​measurements; (ii) one or more delay measurements; (iii) one or more variabilities of delay measurements; and (iv) one or more load measurements.

[0166] The PLR ​​measurement result of each access network may be a PDU packet loss rate of the corresponding access network. Separate measurements may be performed for uplink transmission and downlink transmission.

[0167] The delay measurement result for each access network may be some measurement result of the delay of the corresponding access network, such as the round trip delay or one-way delay of the corresponding access network. The one-way delay from the WTRU to the UPF or from the UPF to the WTRU may be measured. Separate measurements may be made for uplink transmissions and downlink transmissions. The delay measurement result may be denoted by the term "D" herein. Alternatively, the delay measurement result for each access network may be an average value (mean) of the measured round trip delay of the corresponding access network or the measured one-way delay of the corresponding access network.

[0168] The variability of the delay measurement results for each access network can be a measurement result of the variability of packet transmission on the corresponding access network, such as the variability of the round-trip delay or one-way delay of the corresponding access network. The variability measurement can come from different air scheduling mechanisms used for 3GPP access networks and non-3GPP access networks, and / or different transmission paths in the core network that can be used by 3GPP RAN nodes and non-3GPP interconnect nodes (non-3GPP interconnect function (N3IWF), trusted non-3GPP gateway function (TNGF), trusted WLAN interconnect function (TWIF), wired access gateway function (W-AGF)). Separate measurements can be made for uplink transmission and downlink transmission. The variability measurement result can be any of the following: statistical variance of delay, statistical standard deviation of delay, median of delay, kth percentile of delay, maximum observed delay, minimum observed delay, etc. The variability of the delay measurement result can be represented by the term "VAR" in this article.

[0169] The load measurement result of each access network may be a measurement result of the load on the corresponding access network, such as a measurement result of the air load, a transport network load (the load in the core network from the RAN to UPF / UPF to UPF (N3 / N9) interface to the UPF), and a combination of the air load measurement result and the transport network load measurement result. Separate measurements may be made for uplink and downlink. The load measurement result may be denoted as the term "L" herein.

[0170] PLR measurements, delay measurements, and delay variability measurements may be direction specific. For a WTRU, the measurements may be based on an uplink path (from the WTRU to the UPF), and / or for a UPF, the measurements may be based on a downlink path (from the UPF to the WTRU). In the following, measurement results for access networks may be distinguished by underscores. For example, a PLR measurement result for a first access network may be denoted as PLR_1, and a delay measurement result for a second access network may be denoted as D_2. Various thresholds for PLR measurement results (e.g., PLR_threshold A_1, PLR_threshold A_2, PLR_threshold B_1, PLR_threshold B_2, PLR_threshold C_1, PLR_threshold C_2, etc.) are mentioned in the following disclosure. These thresholds may be configured and / or set by the network, and may be configured to be set to the same or different values. The same applies to various thresholds for delay measurement results (D), variability of delay measurement results (VAR), and load measurement results (L), which are mentioned in the following disclosure.

[0171] Representative active to inactive transitions

[0172] The state transition of the dynamic redundant boot mode from the active state to the inactive state may occur, be triggered and / or be performed based on one or more of various measurements, such as any of the measurements disclosed above. As an example, the WTRU and / or UPF may perform the state transition of the dynamic redundant boot mode from the active state to the inactive state based on one or more of various measurements (e.g., based on Figure 4 , at (416A) and / or (416B) and the accompanying disclosure), triggering and / or executing a state transition of a dynamic redundant boot mode from an active state to an inactive state.

[0173] In various embodiments, a state transition of a dynamic redundancy boot mode from an active state to an inactive state may occur, be triggered, and / or be executed in response to, based on, and / or in combination with any one or combination of various conditions that are occurring. The various conditions may include, for example, (i) the PLR measurement of the first access network satisfies (e.g., is less than or equal to) a corresponding first PLR threshold among one or more PLR thresholds (represented herein as "PLR_1 < PLR_threshold_A_1"); (ii) the PLR measurement of the second access network satisfies (e.g., is less than or equal to) a corresponding second PLR threshold among one or more PLR thresholds (represented herein as "PLR_2 < PLR_threshold_A_2"); (iii) the latency measurement of the first access network satisfies (e.g., is less than or equal to) a corresponding first latency threshold among one or more latency thresholds (represented herein as "D_1 < D_threshold_A_1"); (iv) the latency measurement of the second access network satisfies (e.g., is less than or equal to) a corresponding second latency threshold among one or more latency thresholds (represented herein as "D_2 < D_threshold_A_2"); (v) the variability of the latency measurement of the first access network satisfies (e.g., is less than or equal to) a corresponding first variability among one or more variabilities of the latency threshold (represented herein as "VAR_1 < VAR_threshold_A_1"); (vi) the variability of the latency measurement of the second access network satisfies (e.g., is less than or equal to) a corresponding second variability among one or more variabilities of the latency threshold (represented herein as "VAR_2 < VAR_threshold_A_2"); (vii) the load measurement of the first access network satisfies (e.g., is greater than or equal to) a corresponding first load threshold among one or more load thresholds (represented herein as "L_1 > L_threshold_A_1"); (viii) the load measurement of the second access network satisfies (e.g., is greater than or equal to) a corresponding second load threshold among one or more load thresholds (represented herein as "L_2 > L_threshold_A_2"); (ix) the PLR measurement of the first access network satisfies (e.g., is greater than or equal to) a corresponding third PLR threshold among one or more PLR thresholds (represented herein as "PLR_1 > PLR_threshold_B_1"); (x) the PLR measurement of the second access network satisfies (e.g., is greater than or equal to) a corresponding fourth PLR threshold among one or more PLR thresholds (represented as "PLR_2 > PLR_threshold_B_2"); (xi) the latency measurement of the first access network satisfies (e.g., is greater than or equal to) a corresponding third latency threshold among one or more latency thresholds (represented herein as "D_1 > D_threshold_B_1"); (xii) the latency measurement of the second access network satisfies (e.g., is greater than or equal to) a corresponding fourth latency threshold among one or more latency thresholds (represented herein as "D_2 > D_threshold_B_2");(xiii) The variability of the latency measurement results of the first access network satisfies (e.g., is greater than or equal to) the corresponding third variability among one or more variabilities of the latency threshold (represented herein as "VAR_1 > VAR_threshold B_1"); (xiv) The variability of the latency measurement results of the second access network satisfies (e.g., is greater than or equal to) the corresponding fourth variability among one or more variabilities of the latency threshold (represented herein as "VAR_2 > VAR_threshold B_2"); (xv) The load measurement result of the first access network satisfies (e.g., is less than or equal to) the corresponding third load threshold among one or more load thresholds (represented herein as "L_1 < L_threshold B_1"); and (xvi) The load measurement result of the second access network satisfies (e.g., is less than or equal to) the corresponding fourth load threshold among one or more load thresholds (represented herein as "L_2 < L_threshold A_2").;

[0174] When the condition PLR_1 < PLR_threshold A_1 is satisfied, this condition may indicate (e.g., is such an indication) that the first access network may be able to meet the requirements of the SDF (e.g., for a relatively long time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition PLR_1 < PLR_threshold A_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0175] When the condition PLR_2 < PLR_threshold A_2 is satisfied, this condition may indicate (e.g., is such an indication) that the second access network may be able to meet the requirements of the SDF (e.g., for a relatively long time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition PLR_2 < PLR_threshold A_2 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). PLR_threshold A_2 and PLR_threshold A_1 may each have values specific to the second access network and the first access network, respectively, and these values may be the same or different.

[0176] When the condition D_1 < D_threshold A_1 is satisfied, this condition may indicate (e.g., is an indication that) the first access network may be able to meet the requirements of the SDF (e.g., for a relatively long period of time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition D_1 < D_threshold A_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0177] When the condition D_2 < D_threshold A_2 is satisfied, this condition may indicate (e.g., is an indication that) the second access network may be able to meet the requirements of the SDF (e.g., for a relatively long period of time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition D_2 < D_threshold A_2 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). D_threshold A_2 and D_threshold A_1 may have values specific to the second access network and the first access network, respectively, and these values may be the same or different.

[0178] When the condition VAR_1 < VAR_threshold A_1 is satisfied, this condition may indicate (e.g., is an indication that) the first access network may be able to meet the requirements of the SDF (e.g., for a relatively long period of time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition VAR_1 < VAR_threshold A_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0179] When the condition VAR_2 < VAR threshold A_2 is satisfied, this condition may indicate (e.g., is an indication that) the second access network may be able to meet the requirements of the SDF (e.g., for a relatively long period of time), and, alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from the active state to the inactive state based on the satisfaction of the condition VAR_2 < VAR threshold A_2 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). VAR threshold A_2 and VAR threshold A_1 may each have values specific to the second access network and the first access network, respectively, and these values may be the same or different.

[0180] When the condition L_1 > L threshold A_1 is satisfied, this condition may indicate (e.g., is an indication that) the traffic of the SDF should be removed from the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from the active state to the inactive state based on the satisfaction of the condition L_1 > L threshold A_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0181] When the condition L_2 > L threshold A_2 is satisfied, this condition may indicate (e.g., is an indication that) the traffic of the SDF should be removed from the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from the active state to the inactive state based on the satisfaction of the condition L_2 > L threshold A_2 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). L threshold A_2 and L threshold A_1 may each have values specific to the second access network and the first access network, respectively, and these values may be the same or different.

[0182] When the condition PLR_1 > PLR threshold B_1 is satisfied, this condition may indicate (e.g., is an indication that) the redundant transmission on the first access network does not meet the requirements of the SDF (e.g., for a relatively long period of time), and, alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may obviate the need for redundant transmission via the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from the active state to the inactive state based on the satisfaction of the condition PLR_1 > PLR threshold B_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0183] When the condition PLR_2>PLR_thresholdB_2 is met, the condition may indicate (e.g., be such an indication) that redundant transmissions on the second access network do not meet the requirements of the SDF (e.g., for a considerable period of time), and alone or in combination with one or more other conditions that are met and / or not met, the need for redundant transmissions through the second access network may be avoided. The WTRU and / or UPF may trigger and / or perform a state transition of the dynamic redundancy boot mode from an active state to an inactive state based on meeting the condition PLR_2>PLR_thresholdB_2 (e.g., alone or in combination with one or more other conditions that are met and / or not met). PLR_thresholdB_2 and PLR_thresholdB_1 may have values ​​specific to the second access network and the first access network, respectively, and these values ​​may be the same or different.

[0184] When the condition D_1>D_threshold B_1 is met, the condition may indicate (e.g., be such an indication) that redundant transmissions on the first access network do not meet the requirements of the SDF (e.g., for a considerable period of time), and alone or in combination with one or more other conditions that are met and / or not met, the need for redundant transmissions over the first access network may be avoided. The WTRU and / or UPF may trigger and / or perform a state transition of the dynamic redundant boot mode from an active state to an inactive state based on satisfying the condition D_1>D_threshold B_1 (e.g., alone or in combination with one or more other conditions that are met and / or not met).

[0185] When the condition D_2>D_thresholdB_2 is met, the condition may indicate (e.g., be such an indication) that redundant transmissions on the second access network do not meet the requirements of the SDF (e.g., for a considerable period of time), and alone or in combination with one or more other conditions that are met and / or not met, the need for redundant transmissions through the second access network may be avoided. The WTRU and / or UPF may trigger and / or perform a state transition of the dynamic redundant boot mode from an active state to an inactive state based on the condition D_2>D_thresholdB_2 being met (e.g., alone or in combination with one or more other conditions that are met and / or not met). D_thresholdB_2 and D_thresholdB_1 may have values ​​specific to the second access network and the first access network, respectively, and these values ​​may be the same or different.

[0186] When the condition VAR_1 > VAR threshold B_1 is satisfied, this condition may indicate (e.g., be an indication that) the redundant transmission on the first access network does not meet the requirements of the SDF (e.g., for a relatively long time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may avoid the need for redundant transmission via the first access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition VAR_1 > VAR threshold B_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0187] When the condition VAR_2 > VAR threshold B_2 is satisfied, this condition may indicate (e.g., be an indication that) the redundant transmission on the second access network does not meet the requirements of the SDF (e.g., for a relatively long time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may avoid the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition VAR_2 > VAR threshold B_2 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). VAR threshold B_2 and VAR threshold B_1 may have values specific to the second access network and the first access network, respectively, and these values may be the same or different.

[0188] When the condition L_1 < L threshold B_1 is satisfied, this condition may indicate (e.g., be an indication that) it is harmless to retain the redundant transmission via the first access network. The WTRU and / or UPF may not trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition L_1 < threshold B_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0189] When the condition L_2 < L threshold B_2 is satisfied, this condition may indicate (e.g., be an indication that) it is harmless to retain the redundant transmission via the second access network. The WTRU and / or UPF may not trigger and / or execute a state transition of the dynamic redundancy steering mode from an active state to an inactive state based on the satisfaction of the condition L_1 < threshold B_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied).

[0190] The redundant boot mode can be transitioned to inactive based on a first link that meets the requirements of the SDF. Hereinafter, it is assumed that the SDF has requirements for loss, latency, and variability, but it should be understood that these requirements can include any subset of the loss requirement, latency requirement, and variability requirement. For example, the SDF may only have a loss requirement, or the SDF may have a loss requirement and a latency requirement. In addition to the SDF requirements, the transition may also be affected by the load condition of the second link.

[0191] For example, the WTRU and / or UPF can trigger and / or perform a state transition of the redundant boot mode to the inactive state in response to, based on, and / or in combination with one of the links that meets the loss requirement, latency requirement, and variability requirement of the SDF. The WTRU and / or UPF can, for example, trigger and / or perform the state transition by meeting a first trigger condition ("Trigger 1"). Trigger 1 can be as follows:

[0192] Trigger 1: (PLR_1 < PLR_Threshold A_1) and (D_1 < D_Threshold A_1) and (VAR_1 < VAR_Threshold A_1)

[0193] As a second example, the WTRU and / or UPF can trigger and / or perform a state transition of the redundant boot mode to the inactive state in response to, based on, and / or in combination with one of the links that meets the loss requirement, latency requirement, and variability requirement of the SDF and other congested links. The WTRU and / or UPF can, for example, trigger and / or perform the state transition by meeting a second trigger condition ("Trigger 2"). Trigger 2 can be as follows:

[0194] Trigger 2: (PLR_1 < PLR_Threshold A_1) and (D_1 < D_Threshold A_1) and (VAR_1 < VAR_Threshold A_1) and (L_2 > L_Threshold B_2)

[0195] As a third example, when replication is not beneficial, the WTRU and / or UPF can trigger and / or perform a state transition of the redundant boot mode to the inactive state. This may occur when the quality of both links is poor, and even with replication, the system cannot meet the loss requirement, latency requirement, and / or variability requirement of the SDF. The WTRU and / or UPF can, for example, trigger and / or perform the state transition by meeting a third trigger condition ("Trigger 3"). Trigger 3 can be as follows:

[0196] Trigger 3: ((PLR_1 > PLR_Threshold B_1) or (D_1 > D_Threshold B_1) or (VAR_1 > VAR_Threshold B_1)) and ((PLR_2 > PLR_Threshold B_2) or (D_2 > D_Threshold B_2) or (VAR_2 > VAR_Threshold B_2))

[0197] In response to, based on, and / or in conjunction with the transition to the inactive replication state, the WTRU and / or UPF may stop using (e.g., may need to stop) one of the branches. As described above, the WTRU and / or UPF may select a branch that meets the requirements of the SDF. If both branches are able to meet the requirements of the SDF, the WTRU may select one branch to operate. There are various options for making this selection.

[0198] In the first option, the WTRU may randomly select between the two branches. In the second option, the WTRU may select a branch that is configured as a primary branch or an initial branch. In the third option, the WTRU may select a branch based on some pre-configured rules (e.g., always select 3GPP or always select non-3GPP). In the fourth option, the WTRU may select a branch based on some non-performance metrics. For example, the WTRU may select based on the WTRU power state, user preferences, etc. In the fifth option, the WTRU may select a branch based on a default or fallback bootstrap mode. For example, when both branches are able to meet the requirements of the SDF, the WTRU may fall back to active-standby.

[0199] Representative inactive to active transitions

[0200] A state transition of the dynamic redundant boot mode from the inactive state to the active state may occur, be triggered and / or be performed based on one or more of various measurements, such as any of the measurements disclosed above. As an example, the WTRU and / or the UPF may (e.g., based on Figure 4 At (416B) and accompanying disclosure) a state transition of a dynamic redundant boot mode from an active state to an inactive state is triggered and / or performed based on one or more of the various measurements.

[0201] In various embodiments, a state transition of the dynamic redundant boot mode from an active state to an inactive state may occur, be triggered, and / or be performed in response to, based on, and / or in conjunction with any one or combination of various situations occurring. In the following, it is assumed that the single access network used for PDU transmission in the inactive state is the first access network. If the single access network used for PDU transmission in the inactive state is the second access network, an equivalent set of conditions and triggers may apply.

[0202] The various conditions may include, for example, (i) the PLR measurement result of the first access network satisfies (e.g., is greater than or equal to) the corresponding fifth PLR threshold among one or more PLR thresholds (denoted herein as "PLR_1 > PLR_thresholdB_3"); (ii) the latency measurement result of the first access network satisfies (e.g., is greater than or equal to) the corresponding fifth latency threshold among one or more latency thresholds (denoted herein as "D_1 > D_thresholdB_3"); (iii) the variability of the latency measurement result of the first access network satisfies (e.g., is greater than or equal to) the corresponding fifth variability among one or more variabilities of the latency threshold (denoted herein as "VAR_1 > VAR_thresholdB_3"); (iv) the PLR measurement result of the second access network satisfies (e.g., is less than or equal to) the corresponding sixth PLR threshold among one or more PLR thresholds (denoted herein as "PLR_2 < PLR_thresholdC_1"); (iv) the latency measurement result of the second access network satisfies (e.g., is less than or equal to) the corresponding sixth latency threshold among one or more latency thresholds (denoted herein as "D_2 < D_thresholdC_1"); (vi) the variability of the latency measurement result of the second access network satisfies (e.g., is less than or equal to) the corresponding sixth variability among one or more variabilities of the latency threshold (denoted herein as "VAR_2 < VAR_thresholdC_1"); and (vii) the load measurement result of the second access network satisfies (e.g., is less than or equal to) the corresponding fifth load threshold among one or more load thresholds (denoted herein as "L_2 < L_thresholdB_3").

[0203] When the condition PLR_1 > PLR_thresholdB_3 is satisfied, this condition may indicate (e.g., be an indication that) the transmission on the first access network does not meet the requirements of the SDF (e.g., for a relatively long time), and, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may indicate the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundant steering mode from an inactive state to an active state based on the satisfaction of the condition PLR_1 > PLR_thresholdB_3 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). The PLR_thresholdB_3 may have a value specific to the first access network, and this value may be the same as or different from the values of PLR_thresholdA_2, PLR_thresholdA_1, PLR_thresholdB_2, and PLR_thresholdB_1.

[0204] When the condition D_1 > D_threshold B_3 is satisfied, this condition may indicate (e.g., is an indication that) the transmission on the first access network does not meet the requirements of the SDF, and may indicate, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition from an inactive state to an active state of the dynamic redundancy steering mode based on the satisfaction of the condition D_1 > D_threshold B_3 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). D_threshold B_3 may have a value specific to the first access network, and this value may be the same as or different from the values of D_threshold A_2, D_threshold A_1, D_threshold B_2, and D_threshold B_1.

[0205] When the condition VAR_1 > VAR_threshold B_3 is satisfied, this condition may indicate (e.g., is an indication that) the transmission on the first access network does not meet the requirements of the SDF (e.g., for a relatively long period of time), and may indicate, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, the need for redundant transmission via the second access network. The WTRU and / or UPF may trigger and / or execute a state transition from an inactive state to an active state of the dynamic redundancy steering mode based on the satisfaction of the condition VAR_1 > VAR_threshold B_3 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). VAR_threshold B_3 may have a value specific to the first access network, and this value may be the same as or different from the values of VAR_threshold A_2, VAR_threshold A_1, VAR_threshold B_2, and VAR_threshold B_1.

[0206] When the condition PLR_2 < PLR_threshold C_1 is satisfied, it may indicate (e.g., is an indication that) deploying replication (e.g., sending duplicate PDUs) via the second access network can help meet the requirements of the SDF. The WTRU and / or UPF may trigger and / or execute a state transition from an inactive state to an active state of the dynamic redundancy steering mode based on the satisfaction of the condition PLR_2 < PLR_threshold C_1 (e.g., alone or in combination with one or more other conditions that are satisfied and / or not satisfied). PLR_threshold C_1 may have a value specific to the second access network, and this value may be the same as or different from the values of PLR_threshold A_2, PLR_threshold A_1, PLR_threshold B_3, PLR_threshold B_2, and PLR_threshold B_1.

[0207] When the condition D_2 < D_threshold C_1 is satisfied, it can be indicated (e.g., such an indication) that deploying replication (sending duplicate PDUs) via the second access network can help meet the requirements of the SDF. The WTRU and / or UPF can trigger and / or execute a state transition of the dynamic redundancy steering mode from the inactive state to the active state based on the satisfaction of the condition D_2 < D_threshold C_1 (e.g., individually or in combination with one or more other conditions that are satisfied and / or not satisfied). D_threshold C_1 can have a value specific to the second access network, and this value can be the same as or different from the values of D_threshold A_2, D_threshold A_1, D_threshold B_3, D_threshold B_2, and D_threshold B_1.

[0208] When the condition VAR_2 < VAR_threshold C_1 is satisfied, it can be indicated (e.g., such an indication) that deploying replication (e.g., sending duplicate PDUs) via the second access network can help meet the requirements of the SDF. The WTRU and / or UPF can trigger and / or execute a state transition of the dynamic redundancy steering mode from the inactive state to the active state based on the satisfaction of the condition VAR_2 < VAR_threshold C_1 (e.g., individually or in combination with one or more other conditions that are satisfied and / or not satisfied). VAR_threshold C_1 can have a value specific to the second access network, and this value can be the same as or different from the values of VAR_threshold A_2, VAR_threshold A_1, VAR_threshold B_3, VAR_threshold B_2, and VAR_threshold B_1.

[0209] When the condition L_2 < L_threshold B_3 is satisfied, this condition may indicate (e.g., be an indication that) the second access network is not congested, and / or, either alone or in combination with one or more other conditions that are satisfied and / or not satisfied, may indicate that deploying replication (e.g., sending duplicate PDUs) over the second access network can help meet the requirements of the SDF. Since replication over the second access network may not significantly affect the load on the second access network, if transmitting duplicate PDUs over the second access network can help meet the requirements of the SDF, then transmitting duplicate PDUs over the second access network can be harmless. The WTRU and / or UPF may trigger and / or execute a state transition of the dynamic redundancy steering mode from an inactive state to an active state based on the satisfaction of the condition L_2 < L_threshold B_3 (e.g., either alone or in combination with one or more other conditions that are satisfied and / or not satisfied). L_threshold B_3 may have a value specific to the first access network, and this value may be the same as or different from the values of L_threshold A_2, L_threshold A_1, L_threshold B_2, and L_threshold B_1. The redundancy steering mode may be transitioned to active based on a first link failing to meet the requirements of the SDF. Hereinafter, it is assumed that the SDF has requirements for loss, delay, and variability, but it should be understood that these requirements may include any subset of the loss requirement, the delay requirement, and the variability requirement. For example, the SDF may only have a loss requirement, or the SDF may have a loss requirement and a delay requirement. In addition to the SDF requirements, the transition may also be affected by the load condition of the second link.

[0210] For example, the WTRU and / or UPF may trigger and / or execute a state transition of the redundancy steering mode to an active state in response to, based on, and / or in combination with a first access link that fails to meet the loss requirement, the delay requirement, and the variability requirement of the SDF. The WTRU and / or UPF may, for example, trigger and / or execute the state transition by satisfying a fourth trigger condition ("Trigger 4"). Trigger 4 may be as follows:

[0211] Trigger 4: (PLR_1 > PLR_threshold B_3) or (D_1 > D_threshold B_3) or (VAR_1 > VAR_threshold B_3)

[0212] As a second example, the WTRU and / or UPF may trigger and / or execute a state transition of the redundancy steering mode to an active state in response to, based on, and / or in combination with a first access link that fails to meet the loss requirement, the delay requirement, or the variability requirement of the SDF and other links that are not congested. The WTRU and / or UPF may, for example, trigger and / or execute the state transition in response to, based on, and / or in combination with a fifth trigger condition ("Trigger 5"). Trigger 5 may be as follows:

[0213] Trigger 5: ((PLR_1 > PLR threshold B_3) or (D_1 > D threshold B_3) or (VAR_1 > VAR threshold B_3)) and (L_2 < L threshold B_3)

[0214] As a third example, the WTRU and / or UPF may trigger and / or execute a state transition from a redundant boot mode to an active state in response to, based on, and / or in combination with a first access link that fails to meet the loss requirements, latency requirements, or variability requirements of the SDF and the quality of a second access network that enables the use of the second access network to help meet the requirements of the SDF. The WTRU and / or UPF may, for example, trigger and / or execute a state transition in response to, based on, and / or in combination with meeting a sixth trigger condition (“Trigger 6”). In some cases, if the second access network does not meet the loss requirements, latency requirements, or variability requirements of the SDF, then performing a state transition from a redundant boot mode to an active state and sending PDUs over the second access network may have very little advantage. An example of Trigger 6 may be:

[0215] Trigger 6: ((PLR_1 > PLR threshold B_3) or (D_1 > D threshold B_3) or (VAR_1 > VAR threshold B_3)) and ((PLR_2 < PLR threshold C_1) and (D_2 < D threshold C_1) and (VAR_2 < VAR threshold C_1))

[0216] Another example of Trigger 6 may be:

[0217] Trigger 6a: (PLR_1 > PLR threshold B_3) and (PLR threshold B_3 < PLR_2 < PLR threshold C_1)

[0218] The WTRU and / or UPF may determine the state transition of the redundant boot mode based on a two-step process. For example, the WTRU and / or UPF may first determine whether replication over the second access network is “required”, and then may determine whether replication over the second access network is “useful”. In various embodiments, if (e.g., only if) it is determined that replication is required and replication is useful, then the WTRU and / or UPF may execute a state transition of the redundant boot mode from an inactive state to an active state.

[0219] The need for replication may be determined based on one or more of the requirements that are not met. For example, the PLR measured on the first access network may be higher than the loss requirement. As another example, the latency (e.g., RTT) measured on the first access network may be higher than the latency requirement.

[0220] The usefulness of replication may be determined based on one or more (e.g., additional) performance metrics. Examples of performance metrics include: (i) replication may be (e.g., only) useful if the PLR ​​measurement result on the second access network meets (e.g., is below) a configured threshold (e.g., PLR_threshold C_1); (ii) replication may be (e.g., only) useful if the mean of the delay measurement result on the second access network meets (e.g., is less than) a threshold (e.g., D_threshold D_1); (iii) replication may be (e.g., only) useful if the variability of the delay on the second access network is such that a value equal to the mean + standard deviation of the delay meets (e.g., is less than) a threshold (e.g., VAR_threshold C_1); (iv) replication may be (e.g., only) useful if the variability of the delay on the second access network is such that a value equal to the mean + k*standard deviation of the delay meets (e.g., is less than) a threshold (e.g., VAR_threshold C_2); (v) replication may be (e.g., only) useful if the variability of the delay on the second access network is such that a value equal to the mean + k*standard deviation of the delay meets (e.g., is less than) a threshold (e.g., VAR_threshold C_2); (e.g., only) useful if the variability of the delay on the second access network is such that a value equal to the mean - standard deviation of the delay satisfies (e.g., is less than) a threshold (e.g., VAR_Threshold C_3); (vi) if the variability of the delay on the second access network is such that a value equal to the mean - k*standard deviation of the delay satisfies (e.g., is less than) a threshold (e.g., VAR_Threshold C_4), then replication may be (e.g., only) useful; (vii) if the variability of the delay on the second access network is such that a value equal to the mean - standard deviation of the delay < a threshold (e.g., VAR_Threshold C_5) < a value equal to the mean + standard deviation of the delay, then replication may be (e.g., only) useful; and (viii) if the variability of the delay on the second access network is such that a value equal to the mean - k*standard deviation of the delay < a threshold (e.g., VAR_Threshold C_6) < a value equal to the mean + k*standard deviation of the delay, then replication may be (e.g., only) useful.

[0221] In the above, the value of k and these thresholds may be (pre)configured. These values ​​may be based on the type of application, some of which may have values ​​that would make it less likely that a copy would be determined to be useful. The AF may provide these values ​​to the network, which may then pass them to the WTRU in the ATSSS rules and to the UPF in the N4 rules.

[0222] In a first example of a 2-step process, the WTRU and / or UPF may have requirements for loss and delay. In the first step, the transmitting entity may determine that one or both of these requirements are not met on the first access network. For example, the transmitting entity may determine that the PLR ​​may be above a first configured threshold and / or the delay may be above a second configured threshold. Therefore, the result of the first step is that replication is required. In the second step, the transmitting entity may compare the variability of the delay on the second access network with a third threshold. Hereinafter, the variability of the delay is defined as mean + standard deviation (e.g., a value equal to the mean + standard deviation), but it should be understood that it can be any of the described performance metrics. The transmitting entity may determine that the mean + standard deviation of the delay is greater than the third threshold. This may indicate that replication is not useful for the SDF and for the current conditions on the second access network. The transmitting entity may remain in the inactive state. Alternatively, the transmitting entity may determine that the mean + standard deviation of the delay may be less than the third threshold. This may indicate that repetition is useful for the SDF and for the current conditions on the second access network. The transmitting entity may transition to the active state (and replicate the packet).

[0223] Other representative triggers of the redundant boot mode state

[0224] In addition to and / or in lieu of measurement-based triggers (PLR, D, VAR, L), the WTRU and / or UPF may decide to change state based on other trigger conditions. These other trigger conditions may be combined with (e.g., used together with) measurement-based triggers. As an example, the WTRU and / or UPF may trigger and / or perform a state transition to a dynamic redundant boot mode (e.g., based on) one or more of the various measurements, measurement-based triggers, and / or other trigger conditions. Figure 4 , at (416A) and / or (416B) and the accompanying disclosure).

[0225] In a first trigger condition of the other trigger conditions for changing the state of the redundant boot mode, the battery status of the WTRU may trigger the state change. For example, if the battery status is low, the WTRU may want to limit operation to a single access network so that it can shut down the second access network. In this case, if the battery status is below a configured threshold, this may trigger the WTRU to change the state from active to inactive. The WTRU may also have rules to help it select an access network to use in the inactive state based on the access network that uses less power.

[0226] In a second trigger condition of the other trigger conditions for changing the state of the redundant bootstrap mode, a mobility event at the WTRU may trigger a change in state from inactive to active. During a 5G handover, there is an interruption time when the WTRU attempts to switch to the target cell, and during this interruption time, the WTRU may not use its 3GPP access network. For a multi-access PDU session with redundant bootstrap mode, a second access network on a non-3GPP access network may be used during this interruption time. One or more of the following may trigger a transition from inactive to active: (i) the WTRU transmits a measurement report to the source gNB (for example, this may be used for events A2, A3, A4, A5, A6, B1, B2); and (ii) the WTRU receives an RRC reconfiguration message that carries / indicates the configuration for the target cell.

[0227] After redundant transmission is no longer required to resolve the mobility event, the redundant bootstrap mode may transition back to inactive. The transition back to inactive may be triggered by one or more of the following: (i) the WTRU switches to the target cell and transmits an RRC Reconfiguration Complete message to the target gNB; and (ii) the WTRU transmits a measurement report to the source gNB (e.g., this may be used for event A1).

[0228] In a third trigger condition of the other trigger conditions for changing the state of the redundant boot mode, the WTRU may trigger a state change from inactive to active (or from active to inactive) for uplink transmission based on an indication from the network. For example, the indication may come from the UPF. The UPF may transmit an indication to the WTRU to change the state, and if transitioning to inactive, the UPF may also indicate which access network to use.

[0229] In a fourth trigger condition of other trigger conditions for changing the state of redundant boot mode, the UPF may trigger a state change from inactive to active (or from active to inactive) for downlink transmission based on an indication from the WTRU. For example, the WTRU may transmit an indication of the change state to the UPF, and if transitioning to inactive, the WTRU may also indicate which access network to use. The communication of the indication between the WTRU and the UPF (e.g., signaling) may be performed using PMF messages. These messages may include the QoS flow ID, the SDF ID, and / or the requested state change for redundant boot mode.

[0230] In the fifth trigger condition of the other trigger conditions for changing the state of the redundant boot mode, the WTRU may trigger a state change from active to inactive in response to, based on and / or in conjunction with a path switch on a non-3GPP access network. The 5G system may support multiple access PDU sessions with traffic switching between one non-3GPP access network path from the WTRU to the N3IWF in the PLMN and another non-3GPP access network path from the WTRU to the TNGF in the same PLMN. In this case, the WTRU and UPF may have 3 temporarily used access branches: the first access branch passes through 3GPP, the second access branch passes through non-3GPP toward the N3IWF, and the third access branch passes through non-3GPP toward the TNGF. If replication is active during this time, the WTRU and UPF may have various options.

[0231] In the first of these options, the WTRU and / or UPF may decide to disable duplication (transition to inactive) and use only the 3GPP access leg. When the WTRU has completed its path switch on the non-3GPP access network, the WTRU and / or UPF may return to the active state.

[0232] In a second of these options, the WTRU and / or UPF may decide to use only one of the non-3GPP access branches for replication. The non-3GPP access branch that can be used may be selected based on, for example, a configuration received during establishment and / or one or more modifications of a multi-access PDU session. The non-3GPP access branch that can be used may be selected based on performance measurements on two non-3GPP access branches. For example, if one branch meets the PLR ​​criteria and the other branch does not meet the PLR ​​criteria, the WTRU or UPF may decide to favor the branch that meets the PLR ​​criteria. The non-3GPP access branch that can be used may be selected based on the specific implementation or may be randomly selected by the WTRU and / or UPF. The selection of the non-3GPP access branch may be pre-configured (e.g., semi-statically and / or dynamically via any of Layer 1 (L1), Layer 2 (L2), Layer 3 (L3), and / or higher layer communications (including, for example, one or more transmissions that may carry MAC, RRC, and / or other messages and / or information). For example, for a path switch from a source non-3GPP branch to a target non-3GPP branch, the WTRU and the UPF may always use the source non-3GPP branch, or they may always use the target non-3GPP branch.

[0233] In the sixth trigger condition of the trigger conditions for changing the state of the redundant bootstrap mode, the WTRU may trigger a state change from inactive to active in response to, based on and / or in conjunction with a path switch on a 3GPP access network. The 5G system supports traffic switching on a 3GPP access path, from a WTRU to a gNB using a direct path to a WTRU to the gNB using an indirect path (i.e., through a relay device). During a path switch, there is an interruption time during which the WTRU may not use its 3GPP access network. For a multi-access PDU session with redundant bootstrap mode, a second access network on a non-3GPP access network may be used during this interruption time. A path switch may be used as a trigger for transitioning from inactive to active.

[0234] In the seventh trigger condition of the trigger condition for changing the state of the redundant bootstrap mode, the WTRU may trigger a state change from inactive to active in response to, based on and / or in conjunction with a pending radio link failure on a 3GPP path. The WTRU always monitors for RLF failure conditions (e.g., based on physical layer problems). When the WTRU detects that a radio link failure on a 3GPP path is pending, it may decide to trigger a transition to active redundant bootstrap mode to allow some connectivity between the WTRU and the UPF.

[0235] In an eighth trigger condition of other trigger conditions for changing the state of redundant bootstrap mode, the WTRU may trigger a state change from active to inactive based on an overtemperature condition. The WTRU monitors the overtemperature condition and may notify the gNB when the overtemperature condition is met. If redundant bootstrap mode is active for the WTRU and the WTRU detects an overtemperature condition, the WTRU may decide to transition to the inactive state. For example, this may help reduce power or may allow the WTRU to shut down radio components corresponding to the non-3GPP access network.

[0236] In a ninth trigger condition of other trigger conditions for changing the state of redundant boot mode, the WTRU may trigger a state change from active to inactive (and vice versa) based on an indication from the user provided through a user interface. The user may decide to force the WTRU to activate replication or deactivate replication.

[0237] In the tenth trigger condition of other trigger conditions for changing the state of the redundant boot mode, a schedule for activating or deactivating replication may be provided for the WTRU and / or UPF. The network may determine the schedule based on input from the WTRU, one or more application servers, one or more RAN nodes, NWDAF, etc. The schedule may be provided to the WTRU and / or UPF (e.g., semi-statically and / or dynamically via any of L1, L2, L3, etc. communications, including, for example, one or more transmissions that may carry MAC, RRC and / or other messages and / or information). The WTRU and / or UPF may activate and deactivate replication based on the schedule. The WTRU may know from its traffic profile that it will generate traffic with high periodicity. For example, the WTRU may know that every 100 milliseconds, an application generates a packet that requires very high throughput and low latency. For such an example, the WTRU may configure the schedule so that replication is active for 10 milliseconds in every 100 milliseconds.

[0238] In the eleventh trigger condition of the other trigger conditions for changing the state of the redundant bootstrap mode, the WTRU and / or UPF may trigger the change of state based on the other bootstrap modes enabled for other SDFs between the WTRU and / or UPF. For example, if the other bootstrap modes are not enabled, the WTRU and / or UPF may be configured to deactivate duplication, or if the WTRU has used a non-3GPP path for other bootstrap modes, the WTRU and UPF may be configured to activate duplication.

[0239] Representative communication of redundant boot mode state changes

[0240] Reference Figure 6 When the WTRU (or UPF) changes the state of the redundant bootstrap mode, it may be useful to notify the peer entity (UPF (or WTRU)) of the change in state. The communication exchange (600) (e.g., signaling exchange) between the WTRU and the UPF may be performed via any of L1, L2, L3, etc. communications (including, for example, one or more transmissions that may carry MAC, RRC, and / or PMF messages). The PMF message may include a QoS flow ID, a service data flow ID, an active or inactive state of the redundant bootstrap mode, and / or an indication of suspending replication (inactive) and resuming replication (active state). After receiving the PMF message from the WTRU and / or in response to receiving the PMF message from the WTRU, the UPF may notify the affected access network node (602). After receiving the PMF message from the UPF and / or in response to receiving the PMF message from the UPF (604), the WTRU may take any of the following actions: (i) stop measuring on any access network that is removed; and (ii) if necessary, enter IDLE mode on any access network that is removed (606).

[0241] A duration may also be specified in the PMF message. The duration may indicate how long the transition to inactive or active (or vice versa) should be applied. For example, if the WTRU is performing a 5G handover and redundancy is required for a short period of time, a duration (e.g., 3 seconds) may be specified. In this case, the WTRU and / or UPF switches back to inactive after 3 seconds. The same access network that was used before the fast switch to active is reused with the inactive mode.

[0242] More generally, when the WTRU (or UPF) changes the state of the redundant boot mode, it may be useful to notify the peer entity (UPF (or WTRU)) of the change in state using any of L1, L2, L3, etc. communications (e.g., in one or more signaling messages). The signaling message may include one or more of the following information: (i) information indicating a PDU session ID; (ii) information indicating one or more QoS flow IDs; (iii) information indicating one or more SDF IDs; (iv) information indicating an active or inactive state of the redundant boot mode; (v) information indicating a duration of the state for the redundant boot mode (e.g., one redundant boot mode for a single state or one redundant boot mode for each state) ("state duration"); (vi) information indicating a schedule for performing replication ("replication schedule"); (vii) information indicating one or more triggers that cause the state change; and (viii) an indication and / or information indicating a request from the peer to return a link to change the replication state.

[0243] For example, an active or inactive state of redundant boot mode may be provided per PDU session, per QoS flow, or per SDF.

[0244] Each state duration of the redundant bootstrap mode may indicate the time that the redundant bootstrap mode will remain in the inactive state or the active state, for example, after a state transition to inactive or active (or vice versa). As an example, the WTRU may be involved in a 5G handover and redundancy may be required for a period of time (e.g., a short period of time). For this purpose, a state duration (e.g., 3 seconds) for the active (or next occurring) state may be specified. The WTRU and UPF may switch the redundant bootstrap mode back to inactive after 3 seconds. The same access network used before the quick switch to active may be reused with the inactive mode.

[0245] The duplication schedule may be based on a traffic profile that has been determined by the WTRU or UPF. The WTRU (or UPF) may provide the schedule to the UPF (or WTRU). The duplication schedule may indicate one or more time periods during which the redundant bootstrap mode will be active. The WTRU and UPF may switch the redundant bootstrap mode to and from the active state according to the schedule (e.g., perform the switch so as to be active for the entire duration of each time period or start the switch at the beginning and end of each time period).

[0246] The trigger that causes the state change may be determined by the WTRU (or UPF). The WTRU (or UPF) may notify its peer (UPF (or WTRU)) of the trigger that causes the state change. The change in state may be the result of any of the following: user indication, overheat, pending RLF, impending handover, performance metrics (such as PLR, delay, variability of delay, access load), etc.

[0247] For example, when the uplink and downlink may not be in the same redundant boot mode state, an indication and / or information indicating a request from the peer to change the return link of the duplicate state may be used. For example, the uplink may have duplicate activity, but the downlink may have duplicate inactivity. The request from the peer to change the return link of the duplicate state may be used for use cases where the 3GPP path uses frequency division duplex (FDD) and therefore has different performance metrics for the uplink and downlink. In this case, the transmitting entity (WTRU or UPF) on the forward link may notify the receiving entity (UPF or WTRU) that the state should be changed for the return link. The signaling message may notify the peer entity to use the same duplication state as the forward link, or it may specify a specific duplication state for the return link.

[0248] In the following, for ease of presentation, it is assumed that the above information is included in a Repeat State (DS) Information Element (IE) carried in one or more (e.g., signaling) messages. This should be considered as an exemplary implementation. It should be understood that only a subset of the above information may be included in a DS IE, or the information may be included in multiple IEs.

[0249] Communication (e.g., signaling) between the WTRU and the UPF may be performed via any of L1, L2, L3, etc. communications (including, for example, one or more transmissions that may carry MAC, RRC and / or PMF messages and / or information). A new PMF message may be defined to carry this information (e.g., PMFP DUPLICATION STATE). The message may be bidirectional (WTRU to UPF and UPF to WTRU). Alternatively, the IE may be included in an existing PMF message (such as PMFP ACCESS REPORT or PMFP UAD PROVISIONING). Since these messages are unidirectional, they may be redefined as bidirectional. As a third option, the IE may be included in an existing PMF message for the WTRU to UPF direction (such as PMFP ACCESS REPORT or PMFP UAD PROVISIONING), and an equivalent PMF message is defined for the UPF to WTRU direction (such as PMFPACCESS REPORT1 or PMFP UAD PROVISIONING1). In the case where the WTRU and UPF have a QUIC connection (e.g., a MASQUE connection over QUIC), signaling between the WTRU and UPF may be accomplished via QUIC messages. The DS IE may be added in a QUIC message (e.g., a CAPSULE protocol message transmitted over a MASQUE connection). The client (e.g., WTRU) sets this IE in a CAPSULE protocol message transmitted to a server (e.g., a proxy) in a QUIC packet.

[0250] In the case where the WTRU and UPF have a DCCP connection, the DS IE may be added as a new DCCP option in the DCCP request / response message.

[0251] After receiving a signaling message from the WTRU and / or in response to receiving a signaling message from the WTRU, the UPF may perform one or more of the following: (i) notify the affected access node of the activated branch or the deactivated branch; (ii) activate or deactivate repetition based on the request in the signaling message; (iii) store the repetition schedule and the transitions from active to inactive and from inactive to active according to the received schedule; (iv) store the duration of the state transition and the transitions from active to inactive or from inactive to active accordingly; and (v) notify the AF of the change in the repetition state of the redundant boot mode.

[0252] After receiving the signaling message from the UPF and / or in response to receiving the signaling message from the UPF, the WTRU may perform one or more of the following actions: (i) if the redundant bootstrap mode is becoming inactive and an access network is being removed, the WTRU may stop making measurements on any access network being removed; (ii) if the redundant bootstrap mode is becoming inactive and an access network is being added, the WTRU may stop making measurements on any access network being added; (iii) if the redundant bootstrap mode is becoming inactive and an access network is being added, and there are no other SDFs on the access network being removed, the WTRU may stop receiving processing on the added access network; (iv) if the redundant bootstrap mode is becoming inactive and an access network is being added, and there are no existing SDFs on the added access network, the WTRU starts receiving processing on the added access network; (v) if the redundant bootstrap mode is becoming inactive and an access network is being removed, and there are remaining SDFs on the access network being removed, the WTRU may discard any duplicate SDFs received on the removed access network packet; (vi) the WTRU may discard any duplicate packets received on the removed access network at the ATSSS layer; (vii) if the redundant bootstrap mode is becoming inactive and an access network is being added, and there is an existing SDF on the access network being added, the WTRU may (re)start duplicate packetization on the ATSSS layer; (viii) the WTRU may use different measurement criteria on the access network; (ix) if the UPF notifies the WTRU that the redundant bootstrap mode is now inactive and the non-3GPP path is removed, the WTRU may start taking more measurements on the 3GPP path to more quickly determine when the redundant bootstrap mode should become active again; (x) the WTRU may activate or deactivate repetition based on a request in a signaling message; (xi) the WTRU may store the repetition schedule and the transitions from active to inactive and from inactive to active based on the received schedule; (xii) the WTRU may store the duration of the state transition and the transitions from active to inactive or from inactive to active accordingly; (xiii) if necessary, the WTRU may transition to IDLE mode on the removed access network.

[0253] Figure 7 is a flow chart illustrating an example process 700 for use in conjunction with multi-access PDU session establishment and / or modification. The process 700 and the accompanying disclosure herein may be considered to be a Figures 4 to 6 A summary of at least some of the accompanying disclosures, and is considered to cover and / or include various embodiments of the above disclosures, including, for example, Figures 4 to 6 At least some of the accompanying disclosure. Figures 1A to 1DThe process 700 may be performed using the architecture of the communication system 100. Other architectures may also be used to perform the process 700.

[0254] Reference Figure 7 , the WTRU may receive first information via a first network element during a registration process, the first information indicating support for traffic steering (702). In various embodiments, the first network element may be, for example, an AMF. In various embodiments, the first information may include a multi-access PDU session support indicator.

[0255] The WTRU may send second information to the first network element, and the second information may indicate one or more redundant boot mode capabilities of the WTRU (704). In various embodiments, the redundant boot mode capability of the WTRU may be or include ATSSS capability. In various embodiments, the ATSSS capability (the redundant boot mode capability) may include any of support for redundant traffic boot mode, support for duplicate detection, and support for specific boot functionality. In various embodiments, the second information may indicate one of a request to establish a multi-access protocol PDU session or a request to modify a multi-access PDU session. For example, the second information may be a PDU session establishment request or a PDU session modification request, and the PDU session establishment request or the PDU session modification request has information about the redundant boot mode capability of the WTRU.

[0256] The WTRU may, for example, receive third information via a second network element, wherein the third information may indicate one or more rules for redundant boot mode (706). In various embodiments, the third information may indicate a response to the request to establish a multi-access PDU session or the request to modify a multi-access PDU. For example, the third information may be a PDU session establishment request accept message having information about (e.g., indicating) the ATSSS rule for redundant boot mode and at least one of the other rules for redundant boot mode. In various embodiments, the WTRU may expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0257] The WTRU may configure a static or dynamic redundant bootstrap mode for the SDF based on the received rules (708). The WTRU may send one or more PDUs of the SDF in the configured redundant bootstrap mode according to the rules (e.g., at least one of the ATSSS rules or other rules) (710).

[0258] In various embodiments, the redundant boot rules may include information indicating that the redundant boot mode may be “static” or “dynamic.” In various embodiments, receiving information indicating whether (or yes) duplicate detection and discarding is performed is necessary for ASSS-LL steering functionality.

[0259] In various embodiments, a dynamic steering mode is configured, and redundant steering rules (e.g., ATSSS rules) may include information indicating that the initial state of the steering mode may be active or inactive. If inactive, the initial PDU transmission of the service data flow may be through a 3GPP access network or a non-3GPP access network.

[0260] In various embodiments, a dynamic steering mode is configured and the measurement configuration includes thresholds for one or more of: PLR, delay, variability of delay, access load, etc. In various embodiments, the transition from inactive to active occurs only when a single access network cannot meet all requirements of the SDF and all requirements of the SDF can be met using two access networks. The decision can be based on a combination of conditions related to PLR on each access network, delay on each access network, variability of delay on each access network, and load on each access network.

[0261] In various embodiments, the transition from active to inactive may occur only if a single access network is able to meet all requirements of the SDF. This decision may be based on a combination of conditions related to the PLR ​​on each access network, the delay on each access network, the variability of the delay on each access network, and the load on each access network.

[0262] In various embodiments of configuring a dynamic bootstrap mode, the transition may occur based on one or more of: UE battery status, mobility events, based on a message from the network. In various embodiments, the message from the network may include a state duration. In various embodiments, if transitioning to inactive, the message from the network may include an indication of which access network to use.

[0263] Figure 8 800 according to various embodiments. The process 800 and the accompanying disclosure herein may be considered to be Figures 4 to 6 A summary of at least some of the accompanying disclosures, and is considered to cover and / or include various embodiments of the above disclosures, including, for example, Figures 4 to 7 At least some of the accompanying disclosure. Figures 1A to 1D The process 800 may be performed using the architecture of the communication system 100. Other architectures may also be used to perform the process 800.

[0264] Reference Figure 8, the WTRU may receive first information from a network element during a registration process, the first information indicating support for traffic steering (802). In various embodiments, the first network element may be, for example, an AMF. In various embodiments, the first information may be or include a multi-access PDU session support indicator.

[0265] The WTRU may send second information to the first network element, and the second information may indicate one or more redundant boot mode capabilities of the WTRU (804). In various embodiments, the redundant boot mode capability of the WTRU may be or include ATSSS capability. In various embodiments, the ATSSS capability (the redundant boot mode capability) may include any of support for redundant traffic boot mode, support for duplicate detection, and support for specific boot functionality. In various embodiments, the second information may indicate one of a request to establish a multi-access protocol PDU session or a request to modify a multi-access PDU session. For example, the second information may be a PDU session establishment request or a PDU session modification request, and the PDU session establishment request or the PDU session modification request has information about the redundant boot mode capability of the WTRU.

[0266] The WTRU may, for example, receive third information via a second network element, wherein the third information may indicate one or more rules for redundant boot mode (806). In various embodiments, the third information may indicate a response to the request to establish a multi-access PDU session or the request to modify a multi-access PDU. For example, the third information may be a PDU session establishment request accept message having information about (e.g., indicating) at least one of the ATSSS rule for redundant boot mode and other rules for redundant boot mode. In various embodiments, the WTRU may expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0267] The WTRU may send a PDU (808) associated with the multi-access PDU session via at least one of a first access network and a second access network, wherein: (i) the PDU is sent via the first access network and the second access network based on a first rule among the rules and a first value of two or more metrics associated with each of the first access network and the second access network, and (ii) the PDU is sent via one of the first access network and the second access network based on a second rule among the rules and a second value of two or more metrics associated with each of the first access network and the second access network.

[0268] In various embodiments, at least one of the one or more rules indicates that PDU duplication for the redundant boot mode is inactive (or active), and the WTRU may be configured to send the PDU based on the indicated PDU duplication based on the absence of any value for one or more of the metrics associated with each of the first access network and the second access network. In various embodiments, the first rule may indicate that the first access network and the second access network are used under the following conditions: (i) first values ​​of two or more metrics associated with the first access network and (ii) first values ​​of two or more metrics associated with the second access network do not satisfy corresponding thresholds.

[0269] Fig. 9 is a flowchart illustrating an example process 900 according to various embodiments. The process 900 and the accompanying disclosure herein may be considered to be Figures 4 to 6 A summary of at least some of the accompanying disclosures, and is considered to cover and / or include various embodiments of the above disclosures, including, for example, Figures 4 to 8 At least some of the accompanying disclosure. Figures 1A to 1D The process 900 may be performed using the architecture of the communication system 100. Other architectures may also be used to perform the process 900.

[0270] Reference Fig. 9 , the WTRU may send first information to a first network element, the first information indicating one of a request to establish a multi-access PDU session or a request to modify the multi-access PDU session (902). The WTRU may receive second information via a second network element, the second information indicating a response to the request to establish the multi-access PDU session or the request to modify the multi-access PDU session (904). The WTRU may determine first values ​​of a plurality of metrics for a first access network (906). The WTRU may determine second values ​​of the plurality of metrics for a second access network (906). The WTRU may determine, based on a rule for redundant boot mode and the first and second values ​​of the plurality of metrics satisfying a corresponding condition of the rule, to send a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network (908). The WTRU may send the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0271] In various embodiments, the PDU is a PDU of the SDF associated with the multi-access PDU session. In various embodiments, based on the rule, the redundant boot mode is changed from inactive to active under the condition that only one of the first access network and the second access network cannot meet the requirements of the SDF. In various embodiments, based on the rule, the redundant boot mode is changed from active to inactive under the condition that only one of the first access network and the second access network can meet the requirements of the SDF.

[0272] In various embodiments, information is received from the network indicating a duration of the state of the redundant boot mode. In various embodiments, information is received indicating which of the first access network or the second access network to use for the duration. In various embodiments, measurements of either the first access network and the second access network that are removed are suspended for the duration. In various embodiments, on the access network that is removed for the duration, the WTRU transitions to IDLE mode.

[0273] In various embodiments, the first information indicates one or more redundant boot mode capabilities of the WTRU, and wherein the second information indicates one or more rules for redundant boot mode, including the rule.

[0274] In various embodiments, the plurality of metric network elements are access and mobility management functions. In various embodiments, the second network element is a base station. In various embodiments, the second network element is a base station associated with the first access network, the second access network, or a second one of the first access network and the second access network that is different from the first.

[0275] In various embodiments, the plurality of metrics includes any two of packet loss rate, delay, variability of delay, and load.

[0276] In various embodiments, the one or more rules for the redundant boot mode include information indicating that an initial state of the redundant boot mode is one of active and inactive. In various embodiments, an initial PDU of the SDF is sent via the first access network, the second access network, or the one of the first access network and the second access network based on the initial state of the redundant boot mode being one of active and inactive.

[0277] In various embodiments, the one or more rules include information indicating a measurement configuration for the plurality of metrics. In various embodiments of the apparatus, wherein the circuitry is configured to expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU. In various embodiments of the method, the method may include expecting to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0278] In various embodiments of the method, the method may receive third information via the second network element during a registration process, the third information indicating support for traffic steering. In various embodiments of the method, determining to send the PDU may include: determining to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the plurality of metrics satisfying the corresponding condition of the rule, and the rule indicating that PDU replication for the redundant steering mode is not active; and sending the PDU may include: sending the PDU based on the indicated PDU replication.

[0279] In various embodiments of the device, the circuit is configured to determine whether to send or receive a PDU, including: the circuit is configured to determine to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the multiple metrics that satisfy the corresponding conditions of the rule, and the rule indicating that PDU replication for the redundant boot mode is inactive; and the circuit is configured to send the PDU, including: the circuit is configured to send the PDU based on the indicated PDU replication.

[0280] Fig.10 is a flowchart illustrating an example process 1000 according to various embodiments. The process 1000 and the accompanying disclosure herein may be considered to be Figures 4 to 6 A summary of at least some of the accompanying disclosures, and is considered to cover and / or include various embodiments of the above disclosures, including, for example, Figures 4 to 8 At least some of the accompanying disclosure. Figures 1A to 1D The process 1000 may be performed using the architecture of the communication system 100. Other architectures may also be used to perform the process 1000.

[0281] Reference Fig.10, the WTRU may send first information to a first network element, the first information indicating one of a request to establish a multi-access protocol data unit (PDU) session or a request to modify the multi-access PDU session (1002). The WTRU may receive second information via a second network element, the second information indicating a response to the request to establish the multi-access PDU session or the request to modify the multi-access PDU session (1003). The WTRU may determine to send or receive a PDU associated with the multi-access PDU session via (i) the first access network, (ii) the second access network, or (iii) one of the first access network and the second access network based on a rule for redundant boot mode, a first value of a plurality of metrics of the first access network that satisfies a corresponding condition of the rule, and a second value of the plurality of metrics of the second access network that satisfies the corresponding condition of the rule (1006). The WTRU may perform one of sending the PDU and receiving the PDU via the first access network, the second access network, or the one of the first access network and the second access network.

[0282] In various embodiments, the PDU is a PDU of the SDF associated with the multi-access PDU session. In various embodiments, based on the rule, the redundant boot mode is changed from inactive to active under the condition that only one of the first access network and the second access network cannot meet the requirements of the SDF. In various embodiments, based on the rule, the redundant boot mode is changed from active to inactive under the condition that only one of the first access network and the second access network can meet the requirements of the SDF.

[0283] In various embodiments, information is received from the network indicating a duration of the state of the redundant boot mode. In various embodiments, information is received indicating which of the first access network or the second access network to use for the duration. In various embodiments, measurements of either the first access network and the second access network that are removed are suspended for the duration. In various embodiments, on the access network that is removed for the duration, the WTRU transitions to IDLE mode.

[0284] In various embodiments, the first information indicates one or more redundant boot mode capabilities of the WTRU, and wherein the second information indicates one or more rules for redundant boot mode, including the rule.

[0285] In various embodiments, the plurality of metric network elements are access and mobility management functions. In various embodiments, the second network element is a base station. In various embodiments, the second network element is a base station associated with the first access network, the second access network, or a second one of the first access network and the second access network that is different from the first.

[0286] In various embodiments, the plurality of metrics includes any two of packet loss rate, delay, variability of delay, and load.

[0287] In various embodiments, the one or more rules for the redundant boot mode include information indicating that an initial state of the redundant boot mode is one of active and inactive. In various embodiments, an initial PDU of the SDF is sent via the first access network, the second access network, or the one of the first access network and the second access network based on the initial state of the redundant boot mode being one of active and inactive.

[0288] In various embodiments, the one or more rules include information indicating a measurement configuration for the plurality of metrics. In various embodiments of the apparatus, wherein the circuitry is configured to expect to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU. In various embodiments of the method, the method may include expecting to receive information indicating at least one rule for redundant boot mode based on sending the first information indicating the one or more redundant boot mode capabilities of the WTRU.

[0289] In various embodiments of the method, the method may receive third information via the second network element during a registration process, the third information indicating support for traffic steering. In various embodiments of the method, determining to send the PDU may include: determining to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the plurality of metrics satisfying the corresponding condition of the rule, and the rule indicating that PDU replication for the redundant steering mode is not active; and sending the PDU may include: sending the PDU based on the indicated PDU replication.

[0290] In various embodiments of the device, the circuit is configured to determine whether to send or receive a PDU, including: the circuit is configured to determine to send the PDU via the first access network and the second access network based on the rule, the first value and the second value of the multiple metrics that satisfy the corresponding conditions of the rule, and the rule indicating that PDU replication for the redundant boot mode is inactive; and the circuit is configured to send the PDU, including: the circuit is configured to send the PDU based on the indicated PDU replication.

[0291] The following references may have been mentioned above and are incorporated herein by reference in their entirety.

[0292] RFC 8684, TCP Extensions for Multipath Operation with Multiple Addresses;

[0293] 3rd Generation Partnership Project (“3GPP”); Service Requirements for 5G Systems, 3GPP

[0294] TS22.261V18.5.0;

[0295] 3GPP; Technical Specification Group Services and System Aspects; 5G System (5GS) Process; Phase

[0296] Section 2, (Release 17), 3GPP 23.502v17.3.0;

[0297] 3GPP; Technical Specification Group Services and System Aspects; System Architecture of 5G System (5GS);

[0298] Stage 2, (Release 17), 3GPP TS23.501v17.3.0;

[0299] 3GPP; Access traffic steering, switching and diversion in the 5G system (5GS) architecture

[0300] Supported studies, 3GPP TRS23.700-93V17.0.0; and

[0301] SP-211612, New SIDs for Access Traffic Steering, Handover, and Offloading Support in 5G System Architecture; Phase 3, SP-94E, December 14-20, 2021.

[0302] in conclusion

[0303] Although features and elements are provided above in specific combinations, it will be understood by those of ordinary skill in the art that each feature or element may be used alone or in any combination with other features and elements. The present disclosure is not limited to the specific embodiments described in this patent application, which are intended to be illustrative of various aspects. Many modifications and variations can be made without departing from the essence and scope of the present invention, as they will be apparent to those skilled in the art. Unless explicitly provided as such, any element, action or description used in the present application specification should not be understood as being essential or necessary to the present invention. According to the foregoing description, in addition to those listed herein, functionally equivalent methods and devices within the scope of the present disclosure will be apparent to those skilled in the art. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is limited only to the terms of the appended claims and the full range of equivalent forms of such entitled claims. It should be understood that the present disclosure is not limited to a specific method or system.

[0304] For simplicity, the foregoing embodiments are discussed with respect to terminology and structure of infrared capable devices (i.e., infrared transmitters and receivers). However, the embodiments discussed are not limited to these systems, but may be applied to other systems using other forms of electromagnetic waves or non-electromagnetic waves (such as sound waves).

[0305] It should also be understood that the terms used herein are used only for the purpose of describing specific embodiments and are not intended to be limiting. As used herein, the term "video" or the term "image" may mean any of a snapshot, a single image, and / or a plurality of images displayed on a time basis. For example, when referred to herein, the term "user equipment" and its abbreviation "UE", the term "remote" and / or the term "head-mounted display" or its abbreviation "HMD" may mean or include (i) a wireless transmit and / or receive unit (WTRU); (ii) any of a plurality of embodiments of the WTRU; (iii) a wireless and / or wired (e.g., tetherable) device configured with (in particular) some or all of the structure and functionality of the WTRU; (iii) a wireless and / or wired device configured with less than all of the structure and functionality of the WTRU; or (iv), etc. This document is relative to Figures 1A to 1D Details of an example WTRU are provided that may represent any WTRU described herein. As another example, various disclosed embodiments herein above and below are described as utilizing a head mounted display. One skilled in the art will recognize that devices other than head mounted displays may be utilized and that some or all of the present disclosure and various disclosed embodiments may be modified accordingly without undue experimentation. Examples of such other devices may include drones or other devices configured to stream information to provide an adapted reality experience.

[0306] In addition, the methods provided herein may be implemented in a computer program, software, or firmware incorporated into a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (sent via a wired connection or a wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (such as built-in hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)). A processor associated with the software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, MME, EPC, AMF, or any host computer.

[0307] Variations of the methods, devices, and systems provided above are possible without departing from the scope of the present invention. In view of the various embodiments that may be applied, it should be understood that the illustrated embodiments are merely examples and should not be considered to limit the scope of the following claims. For example, the embodiments provided herein include handheld devices that may include or be used with any suitable voltage source (such as a battery, etc.) that provides any suitable voltage.

[0308] In addition, in the embodiments provided above, processing platforms, computing systems, controllers and other devices including processors are indicated. These devices may include at least one central processing unit ("CPU") and memory. According to the practice of those skilled in the art of computer programming, references to the symbolic representations of actions and operations or instructions may be performed by various CPUs and memories. Such actions and operations or instructions may be referred to as being "executed", "computer executed" or "CPU executed".

[0309] Those of ordinary skill in the art will appreciate that the actions and symbolic representations of operations or instructions include manipulation of electrical signals by the CPU. The electrical system represents data bits, which may result in the ultimate transformation of electrical signals or reduction of electrical signals and the retention of data bits at memory locations in the memory system, thereby reconfiguring or otherwise changing the operation of the CPU and performing other processing of signals. The memory location that holds the data bits is a physical location that has specific electrical, magnetic, optical, or organic properties that correspond to or represent the data bits. It should be understood that the embodiments are not limited to the above-mentioned platforms or CPUs, and other platforms and CPUs may also support the provided methods.

[0310] The data bits may also be maintained on computer-readable media, including magnetic disks, optical disks, and any other volatile (e.g., random access memory ("RAM")) or non-volatile (e.g., read-only memory ("ROM")) mass storage system readable by the CPU. The computer-readable media may include cooperating or interconnected computer-readable media that reside solely on the processing system or distributed across multiple interconnected processing systems that may be local or remote relative to the processing system. It should be understood that the embodiments are not limited to the above-mentioned memories, and other platforms and memories may also support the provided methods.

[0311] In an exemplary embodiment, any of the operations, processes, etc. described herein may be implemented as computer-readable instructions stored on a computer-readable medium. The computer-readable instructions may be executed by a processor of a mobile unit, a network element, and / or any other computing device.

[0312] There is little difference between hardware implementation and software implementation of various aspects of the system. The use of hardware or software is usually (but not always, because in some contexts, the choice between hardware and software may become important) a design choice that represents a trade-off between cost and efficiency. There may be various media (e.g., hardware, software, and / or firmware) that can implement the processes and / or systems and / or other technologies described herein, and the preferred media may vary with the context of the deployment process and / or system and / or other technologies. For example, if the implementer determines that speed and accuracy are most important, the implementer may choose a media that is primarily hardware and / or firmware. If flexibility is most important, the implementer may choose a specific implementation that is primarily software. Alternatively, the implementer may choose some combination of hardware, software, and / or firmware.

[0313] The above detailed description has listed various embodiments of the device and / or process by using block diagrams, flow charts and / or examples. In the case where such block diagrams, flow charts and / or examples include one or more functions and / or operations, it should be understood by those skilled in the art that each function and / or operation within such block diagrams, flow charts or examples can be implemented individually and / or collectively by a wide range of hardware, software, firmware or almost any combination thereof. In one embodiment, several parts of the subject matter described herein can be implemented via application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs) and / or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein can be equivalently implemented in integrated circuits as a whole or in part as one or more computer programs running on one or more computers (e.g., one or more programs running on one or more computer systems), one or more programs running on one or more processors (e.g., one or more programs running on one or more microprocessors), firmware or almost any combination thereof, and according to the present disclosure, designing circuits and / or writing software and / or firmware codes will be completely within the technical scope of those skilled in the art. Furthermore, those skilled in the art will appreciate that the mechanisms of the subject matter described herein can be distributed as a program product in a variety of forms, and that the illustrative embodiments of the subject matter described herein apply regardless of the specific type of signal-bearing medium used to actually perform the distribution. Examples of signal-bearing media include, but are not limited to, the following: recordable type media (such as floppy disks, hard drives, CDs, DVDs, digital tapes, computer memory, etc.); and transmission type media (such as digital and / or analog communication media (e.g., fiber optic cables, waveguides, wired communication links, wireless communication links, etc.)).

[0314] Those skilled in the art will recognize that it is common in the art to describe devices and / or processes in the manner set forth herein, and thereafter use engineering practices to integrate such described devices and / or processes into a data processing system. That is, at least a portion of the devices and / or processes described herein can be integrated into a data processing system via a reasonable amount of experimentation. Those skilled in the art will recognize that a typical data processing system generally may include one or more of the following: a system unit housing; a video display device; a memory, such as a volatile memory and a non-volatile memory; a processor, such as a microprocessor and a digital signal processor; a computing entity, such as an operating system, a driver, a graphical user interface, and an application; one or more interactive devices, such as a touch pad or a screen; and / or a control system, including a feedback loop and a control motor (e.g., a feedback for sensing position and / or velocity, a control motor for moving and / or adjusting components and / or quantities). A typical data processing system may be implemented using any suitable commercially available components, such as those typically found in data computing / communication and / or network computing / communication systems.

[0315] The subject matter described herein sometimes illustrates different components included in or connected to different other components. It should be understood that such depicted architectures are merely examples, and in fact many other architectures that achieve the same functionality can be realized. In a conceptual sense, any arrangement of components that achieve the same functionality is effectively "associated" so that the desired functionality can be achieved. Therefore, any two components that are combined to achieve a specific functionality in this article can be considered to be "associated" with each other so that the desired functionality is achieved, regardless of the architecture or intermediate components. Similarly, any two components so associated can also be considered to be "operably connected" or "operably coupled" to each other to achieve the desired functionality, and any two components that can be so associated can also be considered to be "operably coupled" to each other to achieve the desired functionality. Specific examples of operable coupling include, but are not limited to, components that can physically cooperate and / or physically interact and / or components that can wirelessly interact and / or wirelessly interact and / or components that can logically interact and / or components that can logically interact.

[0316] With respect to substantially any plural and / or singular terms used herein, those skilled in the art may translate from the plural to the singular and / or from the singular to the plural as appropriate, as appropriate to the context and / or application. For clarity, various singular / plural arrangements may be explicitly listed herein.

[0317] It will be understood by those skilled in the art that, in general, the terms used herein, and particularly in the appended claims (e.g., the bodies of the appended claims), are generally intended to be "open" terms (e.g., the term "including" should be interpreted as "including but not limited to", the term "having" should be interpreted as "having at least", the term "comprising" should be interpreted as "including but not limited to", etc.). It will also be understood by those skilled in the art that if a specific number of an introduced claim recitation is intended, such intent will be explicitly stated in the claim, and in the absence of such a recitation, there is no such intent. For example, where only one item is intended, the term "single" or similar language may be used. To aid understanding, the following appended claims and / or the description herein may include the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed as implying that any particular claim including such introduced claim recitations is limited to an embodiment including only one such recitation by the indefinite article "a" or "an" to introduce the claim recitation. This is true even when the same claim includes the introductory phrases "one or more" or "at least one" and an indefinite article such as "a" or "a kind" (e.g., "a" and / or "a kind" should be interpreted as meaning "at least one" or "one or more"). The same applies to the use of definite articles used to introduce claim recitations. In addition, even if a specific number of introduced claim recitations is explicitly recited, one skilled in the art will recognize that such recitation should be interpreted as meaning at least the stated number (e.g., a bare recitation of "two recitations" without other modifiers means at least two recitations or two or more recitations). In addition, in those instances where a convention similar to "at least one of A, B, and C, etc." is used, generally speaking, the meaning of such construction is that one skilled in the art will understand the convention (e.g., "a system having at least one of A, B, and C" will include, but is not limited to, a system having A alone, B alone, C alone, A and B simultaneously, A and C simultaneously, B and C simultaneously, and / or A, B, and C simultaneously, etc.). In those instances where a convention similar to "at least one of A, B, or C, etc." is used, generally speaking, the meaning of such construction is that one skilled in the art will understand the convention (e.g., "a system having at least one of A, B, or C" will include, but is not limited to, systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). One skilled in the art will also understand that, in fact, any discrete words and / or phrases presenting two or more alternative terms, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one of the terms, any of the terms, or both of the terms.For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." Additionally, as used herein, the term "any of" followed by a listing of multiple items and / or multiple categories of items is intended to include "any of," "any combination," "any multiples," and / or "any combination of multiples" of the items and / or categories of items, either alone or in combination with other items and / or other categories of items. Additionally, as used herein, the term "set" is intended to include any number of items, including zero. Additionally, as used herein, the term "quantity" is intended to include any quantity, including zero. And, as used herein, the term "plurality" is intended to be synonymous with "multiple."

[0318] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also described in terms of any individual member or subgroup of members of the Markush group.

[0319] As will be understood by those skilled in the art, for any and all purposes (such as for providing a written description), all ranges disclosed herein also encompass any and all possible subranges and combinations of their subranges. Any listed range can be easily identified as fully describing and enabling the same range to be divided into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be easily divided into a lower third, a middle third, and an upper third, etc. As will be understood by those skilled in the art, all languages ​​such as "up to", "at least", "greater than", "less than", etc. include the cited numbers and refer to ranges that can subsequently be divided into subranges as described above. Finally, as will be understood by those skilled in the art, ranges include each individual number. Thus, for example, a group having 1 to 3 units refers to a group having 1, 2, or 3 units. Similarly, a group having 1 to 5 units refers to a group having 1, 2, 3, 4, or 5 units, etc.

[0320] Furthermore, the claims should not be read as limited to the order or elements presented unless otherwise stated. Furthermore, the use of the term "means for..." in any claim is intended to invoke 35 U.S.C. § 112, 6 or means-plus-function claim format, and any claim without the term "means for..." is not intended to be so.

[0321] Suitable processors include, by way of example, a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), an application specific standard product (ASSP), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), and / or state machine.

[0322] The WTRU may be used in conjunction with a module, which may be implemented in hardware and / or software including the following components: Software Defined Radio (SDR) and other components such as a camera, a video camera module, a videophone, a speakerphone, a vibration device, a speaker, a microphone, a television transceiver, a hands-free headset, a keyboard, module, a frequency modulation (FM) radio unit, a near field communication (NFC) module, a liquid crystal display (LCD) display unit, an organic light emitting diode (OLED) display unit, a digital music player, a media player, a video game player module, an internet browser, and / or any wireless local area network (WLAN) or ultra-wideband (UWB) module.

[0323] Although various embodiments have been described in terms of a communication system, it is contemplated that the system may be implemented in software on a microprocessor / general purpose computer (not shown). In certain embodiments, one or more of the functions of the various components may be implemented in software controlling a general purpose computer.

[0324] Furthermore, while the invention has been shown and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made to the details within the scope and range of equivalents of the claims without departing from the invention.

Claims

1. A device supporting access traffic steering, switching and splitting (ATSSS), the device comprising: Transceiver; and A processor; wherein: The transceiver is configured to receive information for establishing a multiple access protocol data unit (PDU) session, the information including first indication information of a first ATSSS rule for a first redundant boot mode (RSM); The transceiver and the processor are configured to: based on the first ASSS rule for the first RSM: Copy the first PDU, and sending the copied first PDU over both the first access network and the second access network; The transceiver is configured to receive information for modifying the PDU session, the information comprising second indication information for a second ATSSS rule for a second RSM, wherein the second indication information for the second ATSSS rule for the second RSM comprises a configured threshold value; and The transceiver and the processor are configured to: based on the second ASSS rule for the second RSM: measuring a performance metric of the first access network; measuring a performance metric of the second access network; and On the condition that the measured performance metrics for both the first access network and the second access network do not satisfy the configured threshold: copying the second PDU; and The copied second PDU is sent over both the first access network and the second access network.

2. The device of claim 1, wherein the transceiver and the processor are further configured to: On the condition that the measured performance metric for the first access network satisfies the configured threshold and the measured performance metric for the second access network does not satisfy the configured threshold: selecting the first access network; and The second PDU is sent on the selected first access network.

3. The device of claim 1 , wherein the transceiver and the processor are further configured to: On the condition that the measured performance metric for the second access network satisfies the configured threshold and the measured performance metric for the first access network does not satisfy the configured threshold: selecting the second access network; and The second PDU is sent on the selected second access network.

4. The device of claim 1, wherein the transceiver and the processor are further configured to: selecting an access network on the condition that the measured performance metrics for both the first access network and the second access network satisfy the configured threshold; and The second PDU is sent on the selected access network.

5. The apparatus of claim 4, wherein the selected access network is one of the first access network or the second access network.

6. The apparatus of claim 5, wherein the selected access network is an initial access network, the initial access network being included in the second ATSSS rule for the second RSM.

7. The apparatus of claim 1, wherein the first RSM is static and the second RSM is dynamic.

8. The apparatus of claim 1, wherein the first ATSSS rule for the first RSM does not include a configured threshold.

9. The apparatus of claim 1 , wherein the apparatus is a wireless transmit / receive unit (WTRU); and wherein: The transceiver is further configured to receive third information indicating support for ASSS from an access and mobility management function (AMF) during a registration procedure; The transceiver and the processor are further configured to send fourth information to the AMF, the fourth information indicating (i) a request to establish a multiple access PDU session and (ii) the RSM capability of the WTRU; wherein the received information for establishing the multiple access PDU session is included in a response to the sent request; The transceiver is further configured to receive a performance management function (PMF) message from a user plane function (UPF); and The transceiver and the processor are further configured to perform at least one of suspending PDU duplication based on the received PMF message or resuming PDU duplication based on the received PMF message.

10. The device of claim 1, wherein the device is a UPF; and wherein: The processor is further configured to determine to perform at least one of suspending PDU copying or resuming PDU copying; and The transceiver and the processor are further configured to send a PMF message to the WTRU, the PMF message indicating that PDU duplication is to be at least one of suspended or resumed.

11. A method for use in a device supporting access traffic steering, switching and splitting (ATSSS), the method comprising: receiving information for establishing a multiple access protocol data unit (PDU) session, the information comprising first indication information of a first ATSSS rule for a first redundant boot mode (RSM); Based on the first ATSSS rule for the first RSM: Copy the first PDU, and sending the copied first PDU over both the first access network and the second access network; receiving information for modifying the PDU session, the information comprising second indication information for a second ATSSS rule for a second RSM, wherein the second indication information for the second ATSSS rule for the second RSM comprises a configured threshold; as well as Based on the second ATSSS rule for the second RSM: measuring a performance metric of the first access network; measuring a performance metric of the second access network; as well as On the condition that the measured performance metrics for both the first access network and the second access network do not satisfy the configured threshold: Copy the second PDU; as well as The copied second PDU is sent over both the first access network and the second access network.

12. The method according to claim 11, further comprising: On the condition that the measured performance metric for the first access network satisfies the configured threshold and the measured performance metric for the second access network does not satisfy the configured threshold: selecting the first access network; as well as The second PDU is sent on the selected first access network.

13. The method according to claim 11, further comprising: On the condition that the measured performance metric for the second access network satisfies the configured threshold and the measured performance metric for the first access network does not satisfy the configured threshold: selecting the second access network; as well as The second PDU is sent on the selected second access network.

14. The method according to claim 11, further comprising: selecting an access network on the condition that the measured performance metrics for both the first access network and the second access network satisfy the configured threshold; as well as The second PDU is sent on the selected access network.

15. The method of claim 14, wherein the selected access network is one of the first access network or the second access network.

16. The method of claim 15, wherein the selected access network is an initial access network, the initial access network being included in the second ATSSS rule for the second RSM.

17. The method of claim 11, wherein the first RSM is static and the second RSM is dynamic.

18. The method of claim 11, wherein the first ASSS rule for the first RSM does not include a configured threshold.

19. The method of claim 11, wherein the device is a wireless transmit / receive unit (WTRU); and the method further comprises: receiving third information indicating support for ASSS from an access and mobility management function (AMF) during a registration procedure; sending fourth information to the AMF, the fourth information indicating (i) a request to establish a multiple access PDU session and (ii) RSM capabilities of the WTRU; wherein the received information for establishing the multiple access PDU session is included in a response to the sent request; receiving a performance management function (PMF) message from a user plane function (UPF); as well as At least one of suspending PDU copying based on the received PMF message or resuming PDU copying based on the received PMF message is performed.

20. The method of claim 11, wherein the device is a UPF; and the method further comprises: Determining to perform at least one of suspending PDU copying or resuming PDU copying; as well as A PMF message is sent to the WTRU indicating that PDU replication is to be at least one of suspended or resumed.

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