Active packet data unit discarding configuration and reporting for extended reality applications

Abstract

A device may receive a quality of service (QoS) profile. The QoS profile may include one or more of an indication to perform active discarding, a reference identifier (ID) associated with a QoS flow, or an indication to report the active discarding. The device may receive a packet data unit (PDU) message that includes a PDU. The PDU message may include a header. The header may include the reference ID and / or a QoS flow ID (QFI). The device may determine, based on the QoS profile, that the PDU is to be discarded. The device may discard the PDU, and / or send a report to a wireless transmit / receive unit (WTRU). The report may include the reference ID and / or an indication that the PDU has been actively discarded. In examples, the QoS profile may further include an indication of a content ratio value that may be used to determine the PDU.

Description

ACTIVE PACKET DATA UNIT DISCARDING CONFIGURATION AND REPORTING FOR EXTENDED REALITY APPLICATIONSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of Provisional U.S. Patent Application No. 63 / 553,915, filed February 15, 2024, the disclosure of which is incorporated herein by reference in its entirety.BACKGROUND

[0002] Mobile communications using wireless communication continue to evolve. A fifth generation may be referred to as 5G. A previous (legacy) generation of mobile communication may be, for example, fourth generation (4G) long term evolution (LTE).SUMMARY

[0003] Systems, methods, and instrumentalities are described herein related to an active discarding technique. In examples, a device may receive a quality of service (QoS) profile. The QoS profile may include one or more of an indication to perform discarding (e.g., active discarding), a reference identifier (ID) associated with a QoS flow, or an indication to report the discarding.

[0004] The device may receive a packet data unit (PDU) message that includes a PDU (e.g., a first PDU). The PDU message may include a header. The header may include the reference ID and / or a QoS flow ID (QFI). The device may determine, based on the QoS profile, that the PDU is to be discarded (e.g., actively discarded). The device may discard the PDU, and / or send a report to a wireless transmit / receive unit (WTRU). The report may include the reference ID and / or an indication that the PDU has been discarded (e.g., actively discarded).

[0005] In examples, the QoS profile may further include an indication of a content ratio value. The content ratio value may indicate a minimum number of PDUs required to reconstruct (e.g., the minimum number of PDUs required for a WTRU application to use application layer forward error correction (AL- FEC) to recover) a PDU set. The device may determine, based on the content ratio value, that one or more PDUs of the PDU set are to be discarded. The device may discard the determined one or more PDUs. The report may further include an indication that the one or more PDUs have been discarded.

[0006] In examples, the QoS profile may include a QFI. The device may determine, based on the indication to perform the discarding and the QFI, that the discarding is to be performed on one or morePDUs associated with the QoS flow (e.g., the QoS flow may be associated with the QFI). The device may determine the one or more PDUs based on the reference ID associated with the QoS flow.

[0007] In examples, the QoS profile may include an indication of a PDU set importance value. The device may determine, further based on the PDU set importance value, that the PDU is to be discarded.

[0008] In examples, the QoS profile may include an indication that the discarding is to be performed for a PDU set that has a size equal to or larger than a PDU set size threshold and that the discarding is not to be performed for a PDU set that has a size smaller than the PDU set size threshold.

[0009] In examples, the QoS profile may further include an indication of a period associated with determining and reporting a number of PDUs that are to be discarded during the period. The report to the WTRU may be sent per the period. The report may further include an indication of the number of PDUs that have been discarded during the period. The QoS profile may further include an indication to send the report via a radio resource control (RRC) message. The report may further indicate at least another PDU that has been discarded.

[0010] In examples, the report may further include an indication that the one or more PDUs were not dropped due to network congestion. The device may determine (e.g., at a later time) an occurrence of the network congestion. The device may disable the discarding based on the occurrence of the network congestion. The device may send a report that includes an indication that the discarding has been disabled. In one or more examples as described herein, the device may be included in a base station.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented;

[0012] FIG. 1 B is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0013] FIG. 1 C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1 A according to an embodiment;

[0014] FIG. 1 D is a system diagram illustrating a further example RAN and a further example CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0015] FIG. 2 illustrates an example for configuring RAN to perform and report active PDU discarding.

[0016] FIG. 3 illustrates an example of activation / deactivation of PDU active dropping feature by theRAN.

[0017] FIG. 4 illustrates an example of PDU active dropping feature, for example, by the RAN.DETAILED DESCRIPTION

[0018] FIG. 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 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 multicarrier (FBMC), and the like.

[0019] As shown in FIG. 1A, the communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a RAN 104 / 113, a ON 106 / 115, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated 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 a “STA”, may be configured to transmit and / or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE.

[0020] The communications systems 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 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 I nternet 110, and / or the 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, a NR NodeB, 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 beappreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0021] 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), relay nodes, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e. , one for each sector of the cell. In an 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 transmit and / or receive signals in desired spatial directions.

[0022] 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).

[0023] More specifically, as noted above, the communications 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, and the like. 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 establish the air interface 115 / 116 / 117 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and / or High-Speed UL Packet Access (HSUPA).

[0024] In an 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), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0025] In an 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).

[0026] In an 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 implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions sent to / from multiple types of base stations (e.g., an eNB and a gNB).

[0027] 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, CDMA2000 EV-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), and the like.

[0028] The base station 114b in FIG. 1 A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, 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 an 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 yet 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 picocell or femtocell. As shown in FIG. 1 A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106 / 115.

[0029] 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 varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 / 115 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, 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, whichmay be utilizing a NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0030] 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 the other networks 112. The PSTN 108 may include circuit- switched telephone networks that provide 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), user datagram protocol (UDP) and / or the internet protocol (IP) in the TCP / IP internet protocol suite. The networks 112 may include wired and / or wireless communications 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.

[0031] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications 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 over different wireless links). For example, the WTRU 102c shown in FIG. 1A 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.

[0032] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1 B, the WTRU 102 may include 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, among others. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0033] 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 in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, 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. While FIG. 1 B depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0034] The transmit / receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In an embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0035] Although the transmit / receive element 122 is depicted in FIG. 1 B 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.

[0036] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit / receive element 122 and to demodulate the signals that are received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and I EEE 802.11 , for example.

[0037] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or 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 the non-removable memory 130 and / or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), 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, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0038] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control the 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, and the like.

[0039] 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 over the air interface 116 from a base station (e.g., base stations 114a, 114b) and / or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable locationdetermination method while remaining consistent with an embodiment.

[0040] The processor 118 may further be coupled to other peripherals 138, which may include one or more software 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 e-compass, a satellite transceiver, a digital camera (for photographs and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (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, and the like. The peripherals 138 may include one or more sensors, the sensors may be one or more of 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.

[0041] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for both the UL (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 to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for either the UL (e.g., for transmission) or the downlink (e.g., for reception)).

[0042] FIG. 1 C is a system diagram illustrating the RAN 104 and the CN 106 according to 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.

[0043] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-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 eNode-Bs 160a, 160b, 160cmay implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a.

[0044] Each of the eNode-Bs 160a, 160b, 160c 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 the UL and / or DL, and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0045] The CN 106 shown in FIG. 1 C 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 are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0046] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, 160c 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, and the like. 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.

[0047] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the RAN 104 via the 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 user planes during inter- eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0048] 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.

[0049] 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 communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves 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 the other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers.

[0050] Although the WTRU is described in FIGS. 1 A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (e.g., temporarily or permanently) wired communication interfaces with the communication network.

[0051] In representative embodiments, the other network 112 may be a WLAN.

[0052] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have an access or an interface to a Distribution System (DS) or another type of wired / wireless network that carries traffic in to and / or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and / or referred to as peer-to- peer traffic. The peer-to-peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11 z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an “ad-hoc” mode of communication.

[0053] When using the 802.11 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width via signaling. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) may be implemented, for example in in 802.11 systems. For CSMA / CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed / 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.

[0054] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0055] Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. The 40 MHz, and / or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. Forthe 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing, and time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0056] Sub 1 GHz modes of operation are supported by 802.11 af and 802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11 af and 802.11 ah relative to those used in 802.11 n, and 802.11ac. 802.11 af supports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non- TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control / Machine-Type Communications, such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g., only support for) certain and / or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0057] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 n, 802.11 ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest 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, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11 ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or Network Allocation Vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode), transmitting to the AP, the entire available frequency bands may be considered busy even though a majority of the frequency bands remains idle and may be available.

[0058] In the United States, the available frequency bands, which may be used by 802.11 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0059] FIG. 1 D is a system diagram illustrating the RAN 113 and the CN 115 according to an embodiment. As noted above, the RAN 113 may employ an NR radio technology to communicate with theWTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0060] 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, gNBs 180a, 108b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a. In an 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 unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and / or gNB 180c).

[0061] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the 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 gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing varying number of OFDM symbols and / or lasting varying lengths of absolute time).

[0062] 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 the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with / connect to gNBs 180a, 180b, 180c while also communicating with / connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for servicing WTRUs 102a, 102b, 102c.

[0063] 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 the UL and / or DL, support of network slicing, dual connectivity, interworking between NR and E- UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control plane information towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1 D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0064] The CN 115 shown in FIG. 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While each of the foregoing elements are depicted as part of the CN 115, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0065] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of NAS signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 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 massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, and / or the like. The AMF 182 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.

[0066] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 115 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 115 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP address, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernetbased, and the like.

[0067] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an 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 andforwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and the like.

[0068] 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 serves 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 the other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local Data Network (DN) 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0069] In view of Figures 1 A-1 D, and the corresponding description of Figures 1 A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and / or any other device(s) described herein, may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0070] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and / or in an operator network environment. For example, the one or more emulation devices may perform the one or more, 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. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and / or may performing testing using over-the-air wireless communications.

[0071] The one or more emulation devices may perform the one or more, including all, functions while not being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and / or a non-deployed (e.g., testing) wired and / or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be testing equipment. Direct RF coupling and / or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0072] Systems, methods, and instrumentalities are described herein related to an active discarding technique. In examples, a device may receive a quality of service (QoS) profile. The QoS profile mayinclude one or more of an indication to perform discarding (e.g., active discarding), a reference identifier (ID) associated with a QoS flow, or an indication to report the discarding.

[0073] The device may receive a packet data unit (PDU) message that includes a PDU (e.g., a first PDU). The PDU message may include a header. The header may include the reference ID and / or a QoS flow ID (QFI). The device may determine, based on the QoS profile, that the PDU is to be discarded (e.g., actively discarded). The device may discard the PDU, and / or send a report to a wireless transmit / receive unit (WTRU). The report may include the reference ID and / or an indication that the PDU has been discarded (e.g., actively discarded).

[0074] In examples, the QoS profile may further include an indication of a content ratio value. The content ratio value may indicate a minimum number of PDUs required to reconstruct (e.g., the minimum number of PDUs required for a WTRU application to use application layer forward error correction (AL- FEC) to recover) a PDU set. The device may determine, based on the content ratio value, that one or more PDUs of the PDU set are to be discarded. The device may discard the determined one or more PDUs. The report may further include an indication that the one or more PDUs have been discarded.

[0075] In examples, the QoS profile may include a QFI. The device may determine, based on the indication to perform the discarding and the QFI, that the discarding is to be performed on one or more PDUs associated with the QoS flow (e.g., the QoS flow may be associated with the QFI). The device may determine the one or more PDUs based on the reference ID associated with the QoS flow.

[0076] In examples, the QoS profile may include an indication of a PDU set importance value. The device may determine, further based on the PDU set importance value, that the PDU is to be discarded.

[0077] In examples, the QoS profile may include an indication that the discarding is to be performed for a PDU set that has a size equal to or larger than a PDU set size threshold and that the discarding is not to be performed for a PDU set that has a size smaller than the PDU set size threshold.

[0078] In examples, the QoS profile may further include an indication of a period associated with determining and reporting a number of PDUs that are to be discarded during the period. The report to the WTRU may be sent per the period. The report may further include an indication of the number of PDUs that have been discarded during the period. The QoS profile may further include an indication to send the report via a radio resource control (RRC) message. The report may further indicate at least another PDU that has been discarded.

[0079] In examples, the report may further include an indication that the one or more PDUs were not dropped due to network congestion. The device may determine (e.g., at a later time) an occurrence of the network congestion. The device may disable the discarding based on the occurrence of the networkcongestion. The device may send a report that includes an indication that the discarding has been disabled. In one or more examples as described herein, the device may be included in a base station.

[0080] Systems, methods, and instrumentalities are described herein related to an active discarding technique. In examples, a device may receive a quality of service (QoS) profile. The QoS profile may include one or more of: an indication of active discarding, a content ratio value for active discarding, and / or a reference identifier (ID). The device may receive one or more downlink packets associated with a packet data unit (PDU) set in a message (e.g., a PDU message). A header of the message may indicate the reference ID. The device may determine, based on at least the QoS profile, that one or more PDUs of the PDU set are to be discarded. The device may send notification information that indicates that one or more PDUs of the PDU set are discarded. The QoS profile may be received from a session management function (SMF). The device may be a radio access network (RAN) node. The notification information may be sent to a wireless transmit / receive unit (WTRU) in a radio resource control (RRC) message. The one or more downlink packets may be received in a general packet radio service tunnelling protocol user plane (GTP-U) message.

[0081] In some examples, the device may receive an indication of active discarding (e.g., from an SMF). The device may determine, based on the indication of active discarding, that a PDU active dropping feature is enabled, the device may send first notification information that indicates that the PDU active dropping feature is enabled. The device may determine, based on a network congestion event, that the PDU active dropping feature is disabled. The device may send second notification information that indicates that the PDU active dropping feature is disabled. The first notification information and the second notification information may be sent to a WTRU in a RRC message. The first notification information and the second notification information may be sent to the SMF.

[0082] An RAN node may be configured by an SMF, for example, based on an indication from the WTRU application at the WTRU, to actively drop one or more PDUs of a PDU set (e.g., according to a certain content ratio). The RAN may be configured to report or notify the WTRU of the dropped PDU(s). The configuration may be received in the QoS profile that may include one or more of the active dropping indication, a content ratio value, as well as a reference ID to allow the RAN and WTRU to identify the traffic being actively dropped.

[0083] In some examples, the RAN may inform the SMF (e.g., via an N2 message) and / or the WTRU (e.g., directly via an RRC message), that the active dropping feature is enabled. If the RAN detects certain event(s) (e.g., a congestion event), the RAN may (e.g., later on) disable the active dropping feature and / or inform the SMF (e.g., via an N2 message) or the WTRU (e.g., directly via an RRC message).

[0084] In one or more examples as described herein, the term “active dropping” and the term “active discarding” may be used interchangeably. In one or more examples as described herein, the termenabli ng / disabli ng of a feature and the term activating / deactivating of a feature may be used interchangeably. In one or more examples as described herein, a PDU may be used to refer to a packet data unit or a protocol data unit, and “packet data unit” and “protocol data unit” may be used interchangeably.

[0085] A RAN node may be configured to apply PDU active discarding and / or send reporting / notification to the WTRU. Active discarding is related to resource preservation and / or optimization, for example, as opposed to discarding due to network congestion.

[0086] A RAN node may perform one or more of the following actions. The RAN node may (e.g., as shown at 2c of FIG. 2) receive a QoS profile (e.g., from an SMF) including information related to PDU active discarding. A QoS profile may indicate one or more QoS attributes associated with a QoS flow (e.g., a QoS flow carrying one or more service flows). The QoS profile may include one or more of the following information: a content ratio value; a reference ID; an association between a QoS flow ID, a content ratio value, a reference ID, a PDU set importance / PDU set size / threshold; or an indication that reporting or notifying the WTRU is to be performed via RRC messaging (e.g., including reporting conditions and / or content). The RAN node may (e.g., as shown at 4 of FIG. 2) receive one or more downlink packets (e.g., pertaining to a PDU set). The packets may be received, for example, in GTP-U messages (e.g., that include reference ID in the GTP-U header of the messages). The RAN node may (e.g., as shown at 5 of FIG. 2) determine, using one or more of the QoS profile, QoS flow ID value, or reference ID, to drop one or more of the received PDUs of the PDU set. The RAN node may (e.g., as shown at 5 of FIG. 2) determine to send a report or notification message to the WTRU, for example, in an RRC message. The RAN node may (as shown at 5 of FIG. 2) send the report or notification to the WTRU, for example, via an RRC message.

[0087] A RAN node may dynamically enabled / disable a PDU active discarding feature based on events (e.g., such as network congestion). A RAN node may perform one or more of the following actions. A RAN node may (e.g., as shown at 0 of FIG. 3) be configured (e.g., by the SMF) to apply PDU active discarding. Configuration may be performed, for example, by receiving a QoS profile with active discarding information (e.g., including a content ratio). A RAN node may (e.g., as shown at Option 1 , 1 a or Option 2, 2a of FIG. 3) determine to enable the PDU active dropping feature. A RAN node may (e.g., as shown at Option 1 , 1a or Option 2, 2a of FIG. 3) send an indication to the SMF (e.g., via N2) or to the WTRU (e.g., via an RRC message) to indicate that the active dropping feature is enabled. A RAN node may (e.g., fourthly, as shown at 1d and 2c of FIG. 3) determine, based on one or more events (e.g., such as network congestion), that the active dropping feature is to be (e.g., needs to be) disabled. A RAN node may (e.g., fifthly, as shown at Option 1 , 1e or Option 2, 2d of FIG. 3) send an indication to the SMF (e.g., via N2) or the WTRU (e.g., via an RRC message) to indicate that the active dropping feature is disabled.

[0088] Extended Reality (XR) media handling may be performed in one or more examples as described herein.

[0089] XR media may be generated, encoded, and / or delivered (e.g., by an XR server) depending on the adaptive media request sent by an XR device. The device may work in one or more (e.g., two) channels. A channel (e.g., a first channel) may be used to accept the XR media stream, and the workflow of decoding, rendering, and displaying may be followed. A channel (e.g., a second channel) may use the tracking sensors to collect 3 degrees of freedom (3DoF) parameters, and translate them into an adaptive media request which may be sent to an XR server by using a delivery system (e.g., 5GS delivery system).

[0090] A base station may be the network entity (e.g., in the 5G system) that is responsible for performing PDU set based QoS handling and / or related functionality on downlink data. A base station that provides PDU set based QoS handling may be configured to consider (e.g., be enhanced to consider) whether traffic in a PDU set is protected, for example, by AL-FEC. The base station may be configured with the content ratio of a PDU set (e.g., each PDU set). The content ratio may be the ratio of PDUs in a PDU set that may be requested (e.g., required) to (e.g., must) be delivered to the WTRU in order for the WTRU application to successfully use the AL-FEC algorithm to recover the complete PDU set. The base station may detect that enough PDUs of a PDU set have been delivered to the WTRU in order for the WTRU application to recover the PDU set and / or then choose to not deliver the rest of the PDU set to the WTRU.

[0091] In examples, an application that uses AL-FEC (e.g., particularly if the AL-FEC algorithm is maximum distance separable) may be able to recover a group of PDUs of a PDU set based on (e.g., based only on) a portion of the PDUs of the PDU Set. The ratio of PDUs that are to be (e.g., needed to be) received to be able to recover the original PDUs may be referred to as a content ratio.

[0092] The base station may be (e.g., may need to be) configured with an AL-FEC awareness based on input from an application.

[0093] The base station (e.g., once the base station is given awareness of the fact that a QoS flow is using AL-FEC) may start dropping packets (e.g., because the base station may know that some packets are not needed to recover the data). In some examples, the application may detect that packets are being dropped and / or conclude that it is to use (e.g., needs to use) a lower bit rate or more FEC (e.g., inaccurately assuming a congestion or low radio quality). The Application may be (e.g., may need to be) informed when the base station actively drops PDUs, for example, based on aspects such as AL-FEC content ratio.

[0094] In one or more examples herein, the 5GS may support a feature where the 5GS informs an application in the WTRU or AS that packets are discarded based on FEC related handling or due to congestion.

[0095] One or more examples herein may be used to describe how a RAN node that supports PDU active dropping feature may be configured to use the active dropping feature, how the RAN may apply the feature and / or report discarded PDUs information to the WTRU. One or more examples herein may be used to describe how the RAN may adaptively enable or disable the PDU active discarding feature, for example, based on certain events or conditions such as network congestion.

[0096] RAN configuration and reporting of PDU active discarding may be implemented.

[0097] An example (e.g., an example procedure) where the RAN node is configured by the 5GS with information regarding PDU active dropping feature related to traffic of interest (e.g., a QoS flow associated with a QFI) may be described in one or more examples as described herein. A WTRU application may send an indication that the feature (e.g., the active dropping feature) may be used and / or supported and may include a content ratio value and / or reporting parameters that are applicable or acceptable to the WTRU application. The 5GS (e.g., the SMF) may receive this indication from the WTRU and determine to configure the serving RAN node of such information (e.g., the SMF may send the serving RAN node an indication indicating that the active dropping feature may be used and / or supported). The RAN node may use the PDU active dropping feature and / or report related dropping information, for example, to the WTRU. FIG. 2 illustrates an example for configuring RAN to perform and report active PDU discarding.

[0098] At 0 of FIG. 2, a PDU session between WTRU and the 5GS may be established to carry user plane traffic for extended reality and media services (XRM).

[0099] At 1 a and 1 b of FIG. 2, the WTRU may be triggered to initiate a packet data unit (PDU) session modification procedure, e.g., to setup / modify quality of service (QoS) flow for XRM traffic.

[0100] An application (e.g., the application hosted in WTRU) may indicate to the WTRU that certain parameters regarding the application traffic may be (e.g., need to be) modified / requested.

[0101] The WTRU may determine (e.g., based on an indication from the application hosted on WTRU) that application layer forward error correction (AL-FEC) is enabled and / or may determine a content ratio. The WTRU may initiate a PDU session modification procedure and / or send a request for QoS treatment for the downlink (DL) flow. The WTRU may indicate requested QoS rules and / or requested QoS flow descriptions. For example, the WTRU may include Requested QoS rules IE indicating requested QoS rules or Requested QoS flow descriptions IE indicating requested QoS flow descriptions. The Requested QoS rules IE may include one or more packet filters which describe the service data flows requested by the WTRU. The QoS parameters (e.g., the specific QoS parameters requested by the WTRU) may be specified in the Requested QoS flow descriptions IE. The QoS parameters may include the content ratio. A content ratio value may indicate the ratio of PDUs of the PDU set requested by the WTRU to be able to reconstruct the original content. A request (e.g., the PDU session modification request as described at 1 b of FIG. 2)may include an indication that a report or notification about actively discarded PDUs related to AL-FEC is to be used (e.g., is needed). The request may include a period over which to account for actively discarded PDUs and send the related report. For example, the request may indicate that the RAN is to (e.g., needs to) send a report to the WTRU regarding actively dropped PDUs every 10 seconds.

[0102] A message (e.g., the message for sending the PDU session modification request) may include a size or threshold (value), to indicate to send a notification if the number of actively discarded PDUs related to FEC reaches the threshold value. For example, the message may indicate that the RAN is to send a notification to the WTRU if 100 PDUs were actively discarded, or every time 100 PDUs are discarded. The message may include a size or threshold value per period. For example, the message may indicate that RAN is to send a notification to WTRU if 100 PDUs were actively dropped over 3 seconds.

[0103] The access and mobility management function (AMF) may receive the WTRU request (e.g., the PDU session modification request) and forward the WTRU request to the serving session management function (SMF).

[0104] At 2a to 2d of FIG. 2, based on the WTRU's request (e.g., the PDU session modification request), the SMF may configure a user plane function (UPF) (e.g., the UPF in FIG. 2) and radio access network (RAN) (e.g., the RAN in FIG. 2).

[0105] The SMF may indicate (e.g., may interact with the PCF to indicate) the requested QoS parameters for the traffic flow of interest. The SMF may provide an indication (e.g., to the policy control function (PCF)) that AL-FEC is enabled for this traffic flow (e.g., along with active PDU discarding parameters that were provided in the request at 1 of FIG. 2).

[0106] The PCF may determine policy and charging control (PCC) rules (e.g., derive new PCC rules or update existing PCC rules) and / or send them to the SMF in 2a of FIG. 2. The SMF may use these PCC rules to determines QoS profile(s) (e.g., new QoS profile(s)) and N4 rules for the RAN and UPF respectively.

[0107] At 2b of FIG. 2, the UPF may be configured with N4 rules. The N4 rules may include, for example, an association between the packet filter for the traffic flow of interest, and the reference ID (e.g., the reference ID derived by the SMF). The UPF may use this indication (e.g., an indication included in the N4 rules) to detect the traffic flow of interest and / or add the reference ID (e.g., in the GTP-U header of the packet when sending it to the RAN over the user plane). The SMF may send the N4 rules to the UPF.

[0108] At 2c of FIG. 2 (e.g., also see at 1 of FIG. 4), the SMF may update the QoS profile for the RAN, for example, with information related to active PDU discarding. For example, the QoS profile may include an indication indicating that active PDU discarding may take place for a certain QoS flow (e.g., with a QoS flow ID (QFI), which may, for example, be included in a header of a PDU message).

[0109] The QoS profile may include (e.g., additionally include) a content ratio value (e.g., the content ratio value for the active discarding for the QoS flow). This value (e.g., the content ratio value) may be derived from the content ratio received by the SMF from the WTRU and / or equal to (e.g., set to be equal to) the content ratio received by the SMF from the WTRU.

[0110] The QoS profile may include a reference ID (e.g., a reference ID associated with the PDU active discarding). The reference ID (e.g., the reference ID associated with a QoS flow) may be used (e.g., by the RAN) to determine which PDU(s) or PDU set(s) of the QoS flow to apply active discarding to. For example, if the QoS flow carries different traffic flows (e.g., different modalities carried in the same QoS flow) associated with (potentially different) content ratios, the QoS profile may include, for the QoS flow, multiple reference IDs (e.g., two reference IDs, one for each traffic flow) and the associated content ratio for active discarding (e.g., the reference ID may be included in the GTP-U header of the PDUs of the PDU set eligible for active discarding.)

[0111] The QoS profile may include association(s) between one or more of: QoS flow I D(s); content ratio value(s); reference I D(s); PDU set importance value(s); or PDU set size(s) (e.g., the QoS profile may include an association between QoS flow ID, content ratio value, reference ID, and PDU set importance value or PDU set size). For example, the QoS profile may include (e.g., an indication) to apply active discarding on PDU sets with PDU set size(s) larger than a value (e.g., large PDU sets) and not apply active discarding on PDU sets with smaller size(s) (e.g., smaller than the value). This association(s) (e.g., the association between PDU set importance value / PDU set size and content ratio) may be provided to the SMF by the WTRU at 2 of FIG. 2.

[0112] The SMF may include (e.g., additionally include) an indication (e.g., a new indication) with the reference ID in the QoS profile. The indication may indicate to the RAN to send notification information associated with active discarding. For example, the indication may tell the RAN that it needs to send an RRC message / report to the WTRU to indicate how much data has been intentionally dropped not due to congestion(s)). The notification information (e.g., the report) may include the reference ID. The indication (e.g., the new indication) may include a period over which the RAN may monitor and / or send the notification information (e.g., the RRC message / report) to the WTRU, for example, regarding actively dropped PDUs. The indication (e.g., the new indication) may include (e.g., additionally include) a threshold value to indicate, for example, that if the number of actively discarded PDUs reaches this threshold value, the RAN is to send (e.g., needs to send) an RRC message / notification to the WTRU.

[0113] The threshold value may indicate, for example, that if the number of PDUs actively dropped within a certain period x reaches a certain value, the RAN is to (e.g., needs to) stop actively dropping for that time period / window (e.g., the quota for actively dropping for that time window is reached). The RANnode may stop actively dropping for a certain amount of time, for example, before it may start actively dropping again.

[0114] At 2d of FIG. 2, the SMF may send a PDU session modification command (e.g., to the WTRU) and / or include the reference I D(s).

[0115] At 3 (e.g., also see 2a of FIG.4) of FIG. 2, downlink data may arrive at (e.g., come to) the base station. The base station may receive the downlink data.

[0116] At 4 (e.g., also see 2b of FIG. 4) of FIG. 2, the UPF may determine that a DL packet matches an N4 rule that is associated with the reference ID. In examples, the UPF may detect that the DL packet matches a service data flow (SDF) or a packet filter, either or both of which the SMF may indicate as being associated with a reference ID.

[0117] The UPF may send a message (e.g., the GTP-U message) with the data packet (e.g., a PDU message may be sent) and / or reference ID to the RAN node.

[0118] At 5 (e.g., also see 3 and 4 of FIG.4) of FIG. 2, the bases station may determine to drop one or more packets according to the content ratio.

[0119] The RAN node (e.g., once the RAN receives the PDUs over the user plane) may determine, using one or more of the QoS profile(s), the QoS flow ID value(s), or reference I D(s) (potentially PDU set size or PDU set importance value), to apply active discarding, and / or use the associated content ratio value to determine how many / which PDUs of the PDU set to drop.

[0120] The RAN may use (e.g., additionally use) the indication (e.g., the new indication) in the QoS profile to determine to send notification information (e.g., an RRC message / report) to the WTRU. The RAN may use the indication to determine if the condition(s) to send the notification information (e.g., an RRC message / report) to the WTRU are met.

[0121] For example, if the RAN is configured with a threshold value for the number of dropped PDUs, and the number of actively dropped PDUs reaches this threshold value, then the RAN may determine to send an RRC message / report to the WTRU.

[0122] If the RAN is configured to send the notification information (e.g., an RRC message / report) to the WTRU periodically (e.g., every certain period), the RAN may determine, if a period has passed, to send the notification information to the WTRU.

[0123] The RAN may prepare the report.

[0124] At 6 (e.g., also see 5 of FIG. 4) of FIG. 2, the RAN may send notification information (e.g., an RRC message / report) to the WTRU. The notification information (e.g., the report) may include the reference ID.

[0125] The notification information (e.g., the report) may indicate, for example, the total number of actively dropped PDUs within a time window.

[0126] The notification information (e.g., the report) may indicate, for example, the total number of PDUs related to certain traffic over the period / time window (e.g., to account for the number of PDUs the RAN received for which AL-FEC was used). For example, this value may account for one or more (e.g., all) PDUs received by RAN over the QoS flow (e.g., with reference ID of value x in the GTP-U header).

[0127] The notification information (e.g., the report) may include (e.g., additionally include) a notification or indication that the number of actively discarded PDUs has reached the threshold value. In this case, the notification information (e.g., the message) may include the period over which this threshold value has been reached (e.g., 200 PDUs were actively dropped, the threshold of 200 is reached, and it took 2 seconds to reach this threshold).

[0128] At 7 of FIG. 2, the WTRU may send the notification information (e.g., the message) to the WTRU application (e.g., XR). The WTRU application (e.g., the XR application) may use the notification information to determine whether and / or how to send adaptive media request(s).

[0129] The WTRU application (e.g., the XR application) may use the notification information (e.g., the message) to determine that a content ratio may be updated (e.g., the content ratio provided earlier may need to be updated, for example, the content ratio may be increased, meaning that fewer PDUs are recommended to be actively dropped by the 5GS, without changing the codec setting, bit rate or other parameters). The WTRU application may determine (e.g., using the report) that missing packets were intentionally dropped by the network (e.g., not due to network congestion) and, therefore, application layer configuration(s) may not need to be changed.

[0130] At 8 of FIG. 2, the WTRU may (e.g., once the WTRU receives the new content ratio) send a content ratio value (e.g., the new content ratio value) to the SMF, for example, using a PDU session modification procedure.

[0131] Active discarding activation / deactivation may be performed, for example, during network congestion(s).

[0132] An example (e.g., an example procedure) for how an RAN node may inform the 5GS (e.g., the SMF) that it supports PDU active discarding feature(s) and / or that the feature(s) is enabled may be described herein. The example (e.g., the procedure) may show how the 5GS (e.g., the RAN or SMF) may send an indication to a WTRU, indicating that the feature is enabled. In some examples, the RAN may (e.g., later) decide to disable the active dropping feature, for example, if the RAN detects congestion(s). The RAN may inform the SMF, and / or the 5GS may notify the WTRU to make proper assessments (e.g., differentiate between packets lost due to congestion(s) (e.g., network congestion) from packets lost due toactive discarding). FIG. 3 illustrates an example of activation / deactivation of PDU active dropping feature by the RAN.

[0133] At 0 of FIG. 3, the SMF may configure a RAN node (e.g., the RAN node serving the WTRU) with a support of PDU active dropping feature(s). For example, the SMF may send a QoS profile to the RAN that includes an active discarding indication. The SMF may include a reference ID, for example, to allow the RAN to determine one or more flows to apply (e.g., eventually apply) the active discarding to.

[0134] In an example, such as Option 1 of FIG. 3, the RAN may determine whether to enable or disable the active dropping feature and / or use the SMF to send this indication (e.g., the indication of whether to enable or disable the active dropping feature) to the WTRU.

[0135] At 1 a of FIG. 3, the RAN node may send a message to the SMF, for example, via N2 interface. This message may indicate that the active dropping feature(s) is enabled or activated. The message may indicate the PDU session ID for which the feature is enabled, and / or a WTRU identifier. The message may include (e.g., additionally include) a reference ID to indicate the traffic for which the feature is to be enabled. The RAN node may indicate a reason (e.g., may include a reason value to reflect the cause of activation of the feature). For example, the message may indicate “saving radio resource while no congestion” as a reason value for activating the feature.

[0136] At 1 b of FIG. 3, the SMF may send a non-access stratum (NAS) message to the WTRU to indicate that the active dropping feature is now enabled. The message may include the PDU session ID for which the feature is enabled. The SMF may provide the content ratio that is to be used by the RAN for this PDU session ID. The SMF may include the reference ID to the WTRU.

[0137] In an example, such as Option 2 of FIG. 3, the RAN may send a message (e.g., an RRC message) to the WTRU (e.g., directly, as shown in 2a of FIG. 3, to indicate that the active dropping feature is enabled). The RAN may include the content ratio that it is to use for this feature with the WTRU traffic. The RAN may include the reference ID (e.g., indicate the reference ID) to the WTRU, for example, to help determine the traffic to which the feature is applied.

[0138] In both Option 1 , 1c and Option 2, 2b of FIG. 3, the WTRU may inform the WTRU application that the active dropping feature is enabled, for example, along with other related information such as the content ratio of use.

[0139] The RAN node may (e.g., later) determine to disable the active dropping feature. For example, in Option 1 , 1 d and Option 2, 2c of FIG. 3, the RAN may detect congestion(s) at the network and / or decide to disable the active dropping feature.

[0140] In Option 1 , at 1e of FIG. 3, the RAN may send a message to the SMF (e.g., via the N2 interface to indicate that the active dropping feature is now disabled). The RAN may include one or more of: areference ID for the traffic of interest, the PDU session ID, or WTRU identifier(s). The RAN may include (e.g., additionally include) a reason value for the deactivation of the feature, e.g., “Congestion detected”.

[0141] At 1f of FIG. 3, the SMF may send a message (e.g., a NAS message) to the WTRU to inform the WTRU that the active dropping feature is disabled / deactivated. The SMF may include, for example, the PDU session ID as well as the reference ID.

[0142] In some examples (e.g., in Option 2, at 2d of FIG. 3), the RAN may send a message (e.g., an RRC message directly) to the WTRU to indicate that the active dropping feature is disabled. The RAN may include a reference ID in this message.

[0143] At 3 of FIG. 3, the WTRU may notify the WTRU application that the active dropping feature is now disabled, or enabled, for example, for the traffic of interest.

[0144] The notification may indicate what / which traffic the feature is enabled or disabled for. For example, the notification may indicate that the feature is enabled or disabled for the whole PDU session. In some examples, the notification may indicate that the feature is enabled or disabled for the certain flow(s) (e.g. destination port numbers) of a PDU session.

[0145] The notification may be sent to the WTRU application, for example, via an Attention (AT) Command.

[0146] The WTRU application may use the notification to detect the reason for missing packets. For example, when the notification indicates that the feature (e.g., the active dropping feature) is enabled, the WTRU application may detect that one or more packets were not received. In examples, if the WTRU application is able to successfully recover the application payloads, the WTRU application may conclude that the missing packets were dropped related to resource preservation (e.g., intentionally dropped by the network in order to conserve network resources). Therefore, the WTRU application may determine that application layer settings (e.g. data rates and codec settings) do not need to change.

[0147] In some examples, when the notification indicates that the feature is disabled, the WTRU application may detect that one or more packets were not received. The WTRU application may conclude that the missing packets were dropped at some point in the network or before the packets reached the network (e.g. due to congestion). Therefore, the WTRU application may determine that application layer settings (e.g. data rates and codec settings) are to be changed (e.g., need to change in order to account for the unreliable nature of the network connectivity).

[0148] An RAN may notify the WTRU of PDU active dropping for a (e.g., each) PDU set.

[0149] In an example (e.g., this example procedure), the RAN node may not need to wait for a period throughout multiple PDU sets to determine to send a report or notification to the WTRU regarding dropped PDUs.

[0150] If the RAN determines (e.g., once the RAN determines), for a PDU set, that active dropping is applied and that remaining PDUs are dropped because active dropping is applied (e.g., the RAN may have successfully delivered a sufficient number of PDUs of the PDU set to the WTRU that the WTRU application is able to recover the original message related to this PDU set), the RAN may send a message (e.g., an RRC message) to the WTRU to inform the WTRU about this. The message from the RAN may indicate to the WTRU that a number of PDUs were actively dropped and / or provide the length of the dropped PDUs of the PDU set or the sequence number of the first discarded PDU of the PDU set (for example, if the WTRU received the first PDU(s) of the PDU set successfully and in order, then the sequence number of the first PDU(s) of the PDU set that was discarded may be useful). This indication may allow the WTRU and / or WTRU application to have a dynamic notification (e.g., a real time notification) regarding the active dropping of PDUs.

[0151] FIG. 4 illustrates an example of PDU active dropping feature by the RAN.

[0152] As shown in FIG. 4, at 1 (e.g., also see 2c of FIG. 2), RAN may receive a quality of service (QoS) profile. The QoS profile may include one or more of an indication to perform active discarding and / or a reference identifier (ID) associated with a QoS flow. At 2a (e.g., also see 3 of FIG. 2), AS may send downlink traffic to UPF. The RAN may be indicated that active discarding is enabled. The RAN may receive PDUs for which active discarding may be performed.

[0153] At 2b (e.g., also see 4 of FIG.2), the RAN may receive a PDU message that includes a DL packet (e.g., a PDU). The PDU message may include a header (e.g., a GTP-U header). The header may include the reference ID and / or a QoS flow ID (QFI). The RAN may determine that one or more PDUs may be discarded.

[0154] At 3 (e.g., also see 5 of FIG. 2), the RAN may perform active discarding (e.g., active PDU dropping) using the QoS profile, a QFI and / or the reference ID. In some examples, active discarding may be performed on a QoS flow (e.g., an entire QoS flow), and / or the RAN may use the QFI (e.g., only the QFI) to determine one or more PDUs to be actively discarded.

[0155] At 4 (e.g., also see 5 of FIG. 2), the RAN may determine to send a report that indicates the active discarding, for example, to a WTRU.

[0156] At 5 (e.g., also see 6 of FIG. 2), the RAN may send the report, for example, via an RRC message, to a WTRU. The report may include the reference ID and / or an indication that the PDU has been actively discarded. For example, the RAN may send an active discarding report to the WTRU so that the WTRU is notified of the cause of the discard.

[0157] Although features and elements described above are described in particular combinations, each feature or element may be used alone without the other features and elements of the preferred embodiments, or in various combinations with or without other features and elements.

[0158] Although the implementations described herein may consider 3GPP specific protocols, it is understood that the implementations described herein are not restricted to this scenario and may be applicable to other wireless systems. For example, although the solutions described herein consider LTE, LTE-A, New Radio (NR) or 5G specific protocols, it is understood that the solutions described herein are not restricted to this scenario and are applicable to other wireless systems as well.

[0159] The processes described above may be implemented in a computer program, software, and / or firmware incorporated in a computer-readable medium for execution by a computer and / or processor. Examples of computer-readable media include, but are not limited to, electronic signals (transmitted over wired and / or wireless connections) and / or computer-readable storage media. Examples of computer- readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as, but not limited to, internal hard disks and removable disks, magneto-optical media, and / or optical media such as compact disc (CD)-ROM disks, and / or digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, terminal, base station, RNC, and / or any host computer.

Claims

Claims1 . A device for packet data unit (PDU) discarding, comprising: a processor configured to: receive a quality of service (QoS) profile, wherein the QoS profile comprises an indication to perform discarding, a reference identifier (ID) associated with a QoS flow, and an indication to report the discarding; receive a PDU message that comprises a first PDU, wherein the PDU message comprises a header, and wherein the header comprises the reference ID; determine, based on the QoS profile, that the first PDU is to be discarded; discard the first PDU; and send a report to a wireless transmit / receive unit (WTRU), wherein the report comprises the reference ID and an indication that the first PDU has been discarded.

2. The device of claim 1 , wherein the discarding is active discarding.

3. The device of any one of claims 1 -2, wherein the QoS profile further comprises an indication of a content ratio value, wherein the content ratio value indicates a minimum number of PDUs required to reconstruct a PDU set, wherein the processor is further configured to: determine, based on the content ratio value, that one or more PDUs of the PDU set are to be discarded; and discard the determined one or more PDUs, wherein the determined one or more PDUs comprises the first PDU, and wherein the report further comprises an indication that the one or more PDUs have been discarded.

4. The device of any one of claims 1 to 3, wherein the QoS profile comprises a QoS flow ID (QFI), and the processor is further configured to: determine, based on the indication to perform the discarding and the QFI, that the discarding is to be performed on one or more PDUs associated with the QoS flow; and determine the one or more PDUs based on the reference ID associated with the QoS flow, wherein the header of the PDU message comprises the QFI, and the determined one or more PDUs comprise the first PDU.

5. The device of any one of claims 1 to 4, wherein the QoS profile comprises an indication of a PDU set importance value, and wherein the determination that the first PDU is to be discarded is further based on the PDU set importance value.

6. The device of any one of claims 1 to 5, wherein the QoS profile further comprises an indication that the discarding is to be performed for a PDU set that has a size equal to or larger than a PDU set size threshold and that the discarding is not to be performed for a PDU set that has a size smaller than the PDU set size threshold.

7. The device of any one of claims 1 to 6, wherein the QoS profile further comprises an indication of a period associated with determining and reporting a number of PDUs that are to be discarded during the period, wherein the report to the WTRU is sent per the period, and wherein the report further comprises an indication of the number of PDUs that have been discarded during the period.

8. The device of any one of claims 1 to 7, wherein the QoS profile further comprises an indication to send the report via a radio resource control (RRC) message.

9. The device of any one of claims 1 to 8, wherein the report further indicates at least another PDU that has been discarded.

10. The device of any one of claims 1 to 9, wherein the report further comprises an indication that the one or more PDUs were not dropped due to network congestion, wherein the processor is further configured to: determine an occurrence of the network congestion; disable the discarding based on the occurrence of the network congestion; and send a report that comprises an indication that the discarding has been disabled.11 . The device of any one of claims 1 to 10, wherein a base station comprises the device.

12. A method for active packet data unit (PDU) discarding, comprising: receiving a quality of service (QoS) profile, wherein the QoS profile comprises an indication to perform discarding, a reference identifier (ID) associated with a QoS flow, and an indication to report the discarding;receiving a PDU message that comprises a first PDU, wherein the PDU message comprises a header, and wherein the header comprises the reference ID; determining, based on the QoS profile, that the first PDU is to be discarded; discarding the first PDU; and sending a report to a wireless transmit / receive unit (WTRU), wherein the report comprises the reference ID and an indication that the first PDU has been discarded.

13. The method of claim 12, wherein the discarding is active discarding.

14. The method of any one of claims 12-13, wherein the QoS profile further comprises an indication of a content ratio value, wherein the content ratio value indicates a minimum number of PDUs required to reconstruct a PDU set, and the method further comprises: determining, based on the content ratio value, that one or more PDUs of the PDU set are to be discarded; and discarding the determined one or more PDUs, wherein the determined one or more PDUs comprises the first PDU, and wherein the report further comprises an indication that the one or more PDUs have been discarded.

15. The method of any one of claims 12-14, wherein the QoS profile comprises a QoS flow ID (QFI), and the method further comprises: determining, based on the indication to perform the discarding and the QFI, that the discarding is to be performed on one or more PDUs associated with the QoS flow; and determining the one or more PDUs based on the reference ID associated with the QoS flow, wherein the header of the PDU message comprises the QFI, and wherein the determined one or more PDUs comprises the first PDU.

16. The method of any one of claims 12 to 15, wherein the QoS profile comprises an indication of a PDU set importance value, and wherein the determination that the first PDU is to be discarded is further based on the PDU set importance value.

17. The method of any one of claims 12 to 16, wherein the QoS profile further comprises an indication that the discarding is to be performed for a PDU set that has a size equal to or larger than a PDU set size threshold and that the discarding is not to be performed for a PDU set that has a size smaller than the PDU set size threshold.

18. The method of any one of claims 12 to 17, wherein the QoS profile further comprises an indication of a period associated with determining and reporting a number of PDUs that are to be discarded during the period, wherein the report to the WTRU is sent per the period, and wherein the report further comprises an indication of the number of PDUs that have been discarded during the period.

19. The method of any one of claims 12 to 18, wherein the QoS profile further comprises an indication to send the report via a radio resource control (RRC) message.

20. The method of any one of claims 12 to 19, wherein the report further comprises an indication that the one or more PDUs were not dropped due to network congestion, wherein the method further comprises: determining an occurrence of the network congestion; disabling the discarding based on the occurrence of the network congestion; and sending a report that comprises an indication that the discarding has been disabled.

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