WO2021237690A1 - Restoration of data service in a standalone network - Google Patents

Restoration of data service in a standalone network Download PDF

Info

Publication number
WO2021237690A1
WO2021237690A1 PCT/CN2020/093310 CN2020093310W WO2021237690A1 WO 2021237690 A1 WO2021237690 A1 WO 2021237690A1 CN 2020093310 W CN2020093310 W CN 2020093310W WO 2021237690 A1 WO2021237690 A1 WO 2021237690A1
Authority
WO
WIPO (PCT)
Prior art keywords
rsd
network
pdu session
data transfer
recover
Prior art date
Application number
PCT/CN2020/093310
Other languages
French (fr)
Inventor
Chaofeng HUI
Jing Zhou
Fojian ZHANG
Hao Zhang
Yuankun ZHU
Quanling ZHANG
Jian Li
Xuesong Chen
Xiuqiu XIA
Original Assignee
Qualcomm Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qualcomm Incorporated filed Critical Qualcomm Incorporated
Priority to PCT/CN2020/093310 priority Critical patent/WO2021237690A1/en
Publication of WO2021237690A1 publication Critical patent/WO2021237690A1/en

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W40/00Communication routing or communication path finding
    • H04W40/02Communication route or path selection, e.g. power-based or shortest path routing
    • H04W40/22Communication route or path selection, e.g. power-based or shortest path routing using selective relaying for reaching a BTS [Base Transceiver Station] or an access point
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L47/00Traffic control in data switching networks
    • H04L47/70Admission control; Resource allocation
    • H04L47/74Admission control; Resource allocation measures in reaction to resource unavailability
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L47/00Traffic control in data switching networks
    • H04L47/70Admission control; Resource allocation
    • H04L47/82Miscellaneous aspects
    • H04L47/826Involving periods of time

Definitions

  • aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for restoring data service in a standalone network.
  • Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts.
  • Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like) .
  • multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE) .
  • LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .
  • UMTS Universal Mobile Telecommunications System
  • a wireless network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) .
  • a user equipment (UE) may communicate with a base station (BS) via the downlink and uplink.
  • the downlink (or forward link) refers to the communication link from the BS to the UE
  • the uplink (or reverse link) refers to the communication link from the UE to the BS.
  • a BS may be referred to as a Node B, a gNB, an access point (AP) , a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G Node B, and/or the like.
  • New Radio which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP) .
  • 3GPP Third Generation Partnership Project
  • NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL) , using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the uplink (UL) , as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.
  • OFDM orthogonal frequency division multiplexing
  • SC-FDM e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)
  • DFT-s-OFDM discrete Fourier transform spread OFDM
  • MIMO multiple-input multiple-output
  • a method of wireless communication may include determining that the UE does not recover from a data transfer stall within a specified amount of time.
  • the UE may be in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) .
  • the method may include transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
  • AMF access and mobility management function
  • a UE for wireless communication may include memory and one or more processors coupled to the memory.
  • the one or more processors may be operatively, electronically, communicatively, or otherwise coupled to the memory.
  • the memory may include instructions executable by the one or more processors to cause the UE to determine that the UE does not recover from a data transfer stall within a specified amount of time.
  • the UE may be in a first PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD.
  • the memory and the one or more processors may be configured to transmit, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
  • an apparatus for wireless communication may include means for determining that the apparatus does not recover from a data transfer stall within a specified amount of time.
  • the apparatus may be in a PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD.
  • the apparatus may also include means for transmitting, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the apparatus does not recover from the data transfer stall within the specified amount of time.
  • aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification.
  • Fig. 1 is a diagram illustrating an example of a wireless network, in accordance with various aspects of the present disclosure.
  • Fig. 2 is a diagram illustrating an example of a base station in communication with a user equipment (UE) in a wireless network, in accordance with various aspects of the present disclosure.
  • UE user equipment
  • Fig. 3 illustrates an example of a 5G architecture, in accordance with various aspects of the present disclosure.
  • Fig. 4 is a diagram illustrating an example of restoring data service in a standalone network, in accordance with various aspects of the present disclosure.
  • Fig. 5 is a diagram illustrating an example process performed, for example, by a UE, in accordance with various aspects of the present disclosure.
  • aspects may be described herein using terminology commonly associated with a 5G or NR radio access technologies (RAT) , aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G) .
  • RAT radio access technologies
  • Fig. 1 is a diagram illustrating an example of a wireless network 100, in accordance with various aspects of the present disclosure.
  • the wireless network 100 may be or may include elements of a 5G (NR) network, an LTE network, and/or the like.
  • the wireless network 100 may include a number of base stations 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities.
  • a base station (BS) is an entity that communicates with user equipment (UEs) and may also be referred to as an NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , and/or the like.
  • Each BS may provide communication coverage for a particular geographic area.
  • the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.
  • a BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell.
  • a macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription.
  • a pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription.
  • a femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) .
  • a BS for a macro cell may be referred to as a macro BS.
  • a BS for a pico cell may be referred to as a pico BS.
  • a BS for a femto cell may be referred to as a femto BS or a home BS.
  • a BS 110a may be a macro BS for a macro cell 102a
  • a BS 110b may be a pico BS for a pico cell 102b
  • a BS 110c may be a femto BS for a femto cell 102c.
  • a BS may support one or multiple (e.g., three) cells.
  • eNB base station
  • NR BS NR BS
  • gNB gNode B
  • AP AP
  • node B node B
  • 5G NB 5G NB
  • cell may be used interchangeably herein.
  • a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS.
  • the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.
  • Wireless network 100 may also include relay stations.
  • a relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS) .
  • a relay station may also be a UE that can relay transmissions for other UEs.
  • a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d.
  • a relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.
  • Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100.
  • macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts) .
  • a network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs.
  • Network controller 130 may communicate with the BSs via a backhaul.
  • the BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.
  • UEs 120 may be dispersed throughout wireless network 100, and each UE may be stationary or mobile.
  • a UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like.
  • a UE may be a cellular phone (e.g., a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.
  • PDA personal digital assistant
  • WLL wireless local loop
  • Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs.
  • MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device) , or some other entity.
  • a wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link.
  • Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices.
  • IoT Internet-of-Things
  • NB-IoT narrowband internet of things
  • UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like.
  • the processor components and the memory components may be coupled together.
  • the processor components e.g., one or more processors
  • the memory components e.g., a memory
  • the processor components and the memory components may be operatively coupled, communicatively coupled, electronically coupled, electrically coupled, and/or the like.
  • any number of wireless networks may be deployed in a given geographic area.
  • Each wireless network may support a particular RAT and may operate on one or more frequencies.
  • a RAT may also be referred to as a radio technology, an air interface, and/or the like.
  • a frequency may also be referred to as a carrier, a frequency channel, and/or the like.
  • Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs.
  • NR or 5G RAT networks may be deployed.
  • two or more UEs 120 may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another) .
  • the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like) , a mesh network, and/or the like.
  • V2X vehicle-to-everything
  • the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.
  • Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.
  • Fig. 2 is a diagram illustrating an example 200 of a base station 110 in communication with a UE 120 in a wireless network 100, in accordance with various aspects of the present disclosure.
  • Base station 110 may be equipped with T antennas 234a through 234t
  • UE 120 may be equipped with R antennas 252a through 252r, where in general T ⁇ 1 and R ⁇ 1.
  • a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS (s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols.
  • MCS modulation and coding schemes
  • Transmit processor 220 may also generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) , a demodulation reference signal (DMRS) , and/or the like) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) .
  • a transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t.
  • MIMO multiple-input multiple-output
  • Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively.
  • antennas 252a through 252r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively.
  • Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples.
  • Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols.
  • a MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols.
  • a receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280.
  • a channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , and/or the like.
  • RSRP reference signal received power
  • RSSI received signal strength indicator
  • RSRQ reference signal received quality
  • CQI channel quality indicator
  • one or more components of UE 120 may be included in a housing 284.
  • Network controller 130 may include communication unit 294, controller/processor 290, and memory 292.
  • Network controller 130 may include, for example, one or more devices in a core network.
  • Network controller 130 may communicate with base station 110 via communication unit 294.
  • a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports that include RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , and transmitted to base station 110.
  • the UE 120 includes a transceiver.
  • the transceiver may include any combination of antenna (s) 252, modulators and/or demodulators 254, MIMO detector 256, receive processor 258, transmit processor 264, and/or TX MIMO processor 266.
  • the transceiver may be used by a processor (e.g., controller/processor 280) and memory 282 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-5.
  • the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120.
  • Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240.
  • Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244.
  • Base station 110 may include a scheduler 246 to schedule UEs 120 for downlink and/or uplink communications.
  • the base station 110 includes a transceiver.
  • the transceiver may include any combination of antenna (s) 234, modulators and/or demodulators 232, MIMO detector 236, receive processor 238, transmit processor 220, and/or TX MIMO processor 230.
  • the transceiver may be used by a processor (e.g., controller/processor 240) and memory 242 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-5.
  • Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform one or more techniques associated with restoring data service in a standalone (SA) network, as described in more detail elsewhere herein.
  • controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform or direct operations of, for example, process 500 of Fig. 5 and/or other processes as described herein.
  • Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively.
  • memory 242 and/or memory 282 may include a non-transitory computer-readable medium storing one or more instructions (e.g., code, program code, and/or the like) for wireless communication.
  • the one or more instructions when executed (e.g., directly, or after compiling, converting, interpreting, and/or the like) by one or more processors of the base station 110 and/or the UE 120, may cause the one or more processors, the UE 120, and/or the base station 110 to perform or direct operations of, for example, process 500 of Fig. 5 and/or other processes as described herein.
  • executing instructions may include running the instructions, converting the instructions, compiling the instructions, interpreting the instructions, and/or the like.
  • UE 120 may include means for determining that the UE does not recover from a data transfer stall within a specified amount of time, where the UE is in a first protocol data unit (PDU) session, in an NR standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) , means for transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time, and/or the like.
  • PDU protocol data unit
  • SA NR standalone
  • AMF access and mobility management function
  • such means may include one or more components of UE 120 described in connection with Fig. 2, such as controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.
  • While blocks in Fig. 2 are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components.
  • the functions described with respect to the transmit processor 264, the receive processor 258, and/or the TX MIMO processor 266 may be performed by or under the control of processor 280.
  • Fig. 2 is provided as an example. Other examples may differ from what is described with regard to Fig. 2.
  • Fig. 3 illustrates an example 300 of a 5G architecture, in accordance with various aspects of the present disclosure.
  • the 5G architecture may include a next generation radio access network (NG-RAN) , which may include one or more base stations, such as base station 110, that communicate with a UE, such as UE 120, over a Uu interface.
  • the Uu interface is a radio interface between the UE and the NG-RAN.
  • the 5G architecture may include a core network (5GC) that provides communications between the NG-RAN and the outside world, including devices that may act as system information servers, such as mobile network operator servers, cloud servers, third-party servers, servers of companies that may provide data and services to the UE through applications on the UE, and/or the like.
  • NG-RAN next generation radio access network
  • 5GC core network
  • the 5GC may include a unified data management (UDM) entity that makes relevant data available to an access and mobility management function (AMF) entity and a session management function (SMF) entity.
  • the AMF entity manages UE network registration, manages mobility, maintains a non-access stratum (NAS) signaling connection with the UE, and manages a registration procedure of the UE with a network.
  • the SMF entity manages sessions and allocates IP addresses to the UE.
  • the 5GC includes a user plane function (UPF) entity that manages user traffic to and from the UE through the NG-RAN and enforces a quality of service (QoS) .
  • UPF user plane function
  • the 5GC includes a policy and control function (PCF) entity that implements charging rules, implements flow control rules, manages traffic priority, and manages a QoS for user subscription services.
  • PCF policy and control function
  • the 5GC may include a unified data repository (UDR) entity that stores structured data for exposure to network functions and a network exposure function (NEF) entity that securely exposes services and capabilities provided by 3GPP network functions.
  • UDR unified data repository
  • NEF network exposure function
  • the 5GC also includes an application function (AF) entity that supports application functionality, influences traffic routing, and interacts with the PCF entity.
  • AF application function
  • 4G Long Term Evolution uses evolved packet system (EPS) bearers, each assigned an EPS bearer identifier (ID)
  • 5G uses QoS flows, each identified by a QoS flow ID (QFI) .
  • the QoS flow is where policy and charging are enforced. All traffic within the same QoS flow may receive the same treatment.
  • EPS evolved packet system
  • QFI QoS flow ID
  • the QoS flow is where policy and charging are enforced. All traffic within the same QoS flow may receive the same treatment.
  • GPRS general packet radio service
  • GTP general packet radio service
  • the gNB may map individual QoS flows to one more dedicated radio bearers (DRBs) .
  • DRBs dedicated radio bearers
  • a PDU session may contain multiple QoS flows and several DRBs, but only a single N3 GTP-U tunnel.
  • a DRB may transport one or more QoS flows. In sum, these entities permit user data traffic or other types of information to be transmitted on a user plane.
  • UE policies for 5G include a UE route selection policy (URSP) and an access network discovery and selection policy (ANDSP) .
  • the UE policies may be delivered to the UE by the PCF, which interfaces to both the AMF and the SMF.
  • the URSP enables the UE to determine how a certain application should be handled in the context of an existing or new PDU session.
  • a PDU session defines the association between the UE and the a network that provides a PDU connectivity service.
  • Each PDU session may be identified by a PDU session ID, and includes one or more QoS flows and QoS rules.
  • the URSP may be defined as a set of one or more URSP rules.
  • Each URSP rule may include a precedence value of the URSP rule as compared to other URSP rules, a traffic descriptor, and one or more RSDs.
  • Each RSD may include one or more parameters such as a precedence value, a PDU session type, a session and service continuity mode, network slice selection assistance information, a data network name, a multi-access preference, an offload indication, and/or the like.
  • Fig. 3 is provided as an example. Other examples may differ from what is described with regard to Fig. 3.
  • the UE may establish a PDU session.
  • the UE may transmit a PDU session establishment request based at least in part on one or more parameters specified by a first RSD.
  • the UE may experience a data transfer stall due to a temporary or permanent network issue.
  • the UE may determine there is a data transfer stall if an expected data transfer does not occur when expected or if data transfers stop for a certain period of time.
  • the UE may not recover for some time from the data transfer stall, providing a user of the UE a bad experience.
  • the UE may waste time, power, and processing resources waiting for the data transfer stall to recover, and the data transfer stall may never recover.
  • the UE may determine that the data transfer stall has not recovered within a specified amount of time, release the PDU session, and establish a new PDU session with the next RSD. In this way, the UE may save time, power, and processing resources instead of waiting for a data transfer stall recovery that may never come.
  • Fig. 4 is a diagram illustrating an example 400 of restoring data service in an SA network, in accordance with various aspects of the present disclosure.
  • Fig. 4 illustrates a UE (e.g., a UE 120 depicted in Figs. 1 and 2, the UE in Fig. 3) that is registered to an NG-RAN of an SA network.
  • the UE may communicate with an AMF of the SA network, where the AMF is associated with one or more UPFs (e.g., UPF1, UPF2) .
  • UPFs e.g., UPF1, UPF2
  • the UE may establish a PDU session.
  • the UE may transmit a PDU session establishment request based at least in part on one or more parameters specified by a first RSD (e.g., RSD1) .
  • RSD1 may map to UPF1, and as shown by reference number 410, the AMF may select UPF1.
  • the UE may receive a PDU session establishment accept message.
  • the UE may experience a data transfer stall due to a temporary or permanent network issue.
  • the UE may trigger a data transfer stall timer when a data transfer stall is detected (e.g., data transfers stop for a threshold amount of stall time) .
  • the timer may be set to an amount of time that is based at least in part on a type of service (e.g., data call, streaming application, and/or the like) associated with the data transfer stall. For example, the amount of time may be shorter for more time-sensitive applications or for applications that may be impacted more than other applications.
  • the UE may keep checking the timer if no data transfers occur or if not all of the expected data transfers occur. As shown by reference number 425, the UE may determine that the data transfer stall has not recovered before expiration of the timer, or within a specified amount of time.
  • the UE may transmit a PDU session release request to the AMF for the PDU session (that uses RSD1) based at least in part on determining that the data transfer stall has not recovered before expiration of the timer or within the specified amount of time.
  • the UE may transmit a PDU session establishment request that is based at least in part on one or more parameters specified by RSD2, which maps to UPF2.
  • RSD2 may be the next RSD in a sequence of RSDs, which may be ordered from highest precedence to lowest precedence.
  • the AMF may select UPF2, which is mapped to RSD2.
  • the UE may receive a PDU session establishment accept message, as shown by reference number 445.
  • the UE may have data service restored, as shown by reference number 450.
  • the next RSD (e.g., RSD3) in the sequence of RSDs may be used to establish the next PDU session.
  • the quantity of RSDs in the sequence of RSDs may be based at least in part on an operator configuration. For example, there may be 8 RSDs in the sequence of RSDs. In some aspects, there may be greater or fewer RSDs.
  • the UE may progress through the sequence of RSDs, as necessary, without waiting too long for a data transfer stall to recover for a first RSD.
  • Fig. 4 is provided as an example. Other examples may differ from what is described with regard to Fig. 4.
  • Fig. 5 is a diagram illustrating an example process 500 performed, for example, by a UE, in accordance with various aspects of the present disclosure.
  • Example process 500 is an example where the UE (e.g., a UE 120 depicted in Figs. 1 and 2, the UE depicted in Figs. 3 and 4, and/or the like) performs operations associated with restoring data service in an SA network.
  • the UE e.g., a UE 120 depicted in Figs. 1 and 2, the UE depicted in Figs. 3 and 4, and/or the like
  • performs operations associated with restoring data service in an SA network e.g., a UE 120 depicted in Figs. 1 and 2, the UE depicted in Figs. 3 and 4, and/or the like.
  • process 500 may include determining that the UE does not recover from a data transfer stall within a specified amount of time (block 510) .
  • the UE e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like
  • the UE is in a first PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD.
  • process 500 may include transmitting, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time (block 520) .
  • the UE e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like
  • Process 500 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.
  • the second RSD is a next RSD in a sequence of RSDs.
  • the first RSD has a higher precedence than the second RSD.
  • the first RSD is associated with a first UPF
  • the second RSD is associated with a second UPF.
  • process 500 includes transmitting a PDU session release request for the first PDU session.
  • transmitting the PDU session establishment request includes transmitting the PDU session establishment request based at least in part on the transmitting the PDU session release request.
  • process 500 includes starting a timer based at least in part on the data transfer stall, and transmitting, to the AMF, a PDU session release request for the first PDU session based at least in part on expiration of the timer.
  • process 500 includes transmitting, to the AMF, a PDU session establishment request with one or more parameters specified by a third RSD, based at least in part on a determination that the UE does not recover from the data transfer stall with the PDU session establishment request with the one or more parameters specified by the second RSD.
  • process 500 includes configuring the specified amount of time based at least in part on a type of service associated with the data transfer stall.
  • process 500 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 5. Additionally, or alternatively, two or more of the blocks of process 500 may be performed in parallel.
  • the term “component” is intended to be broadly construed as hardware, software, and/or a combination of hardware and software.
  • a processor is implemented in hardware, software, and/or a combination of hardware and software.
  • Software is to be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and/or the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.
  • satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.
  • “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .
  • the phrase “only one” or similar language is used.
  • the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms.
  • the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.
  • the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or, ” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of” ) .

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine that the UE does not recover from a data transfer stall within a specified amount of time. The UE is in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD). The UE may transmit, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time. Numerous other aspects are provided.

Description

RESTORATION OF DATA SERVICE IN A STANDALONE NETWORK
FIELD OF THE DISCLOSURE
Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for restoring data service in a standalone network.
BACKGROUND
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like) . Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE) . LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .
A wireless network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) . A user equipment (UE) may communicate with a base station (BS) via the downlink and uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP) , a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G Node B, and/or the like.
The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New Radio (NR) , which may also be referred to as 5G, is a set of enhancements to the  LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP) . NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL) , using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the uplink (UL) , as well as supporting beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation. As the demand for mobile broadband access continues to increase, further improvements in LTE, NR, and other radio access technologies remain useful.
SUMMARY
In some aspects, a method of wireless communication, performed by a user equipment (UE) , may include determining that the UE does not recover from a data transfer stall within a specified amount of time. The UE may be in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) . The method may include transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
In some aspects, a UE for wireless communication may include memory and one or more processors coupled to the memory. For example, the one or more processors may be operatively, electronically, communicatively, or otherwise coupled to the memory. The memory may include instructions executable by the one or more processors to cause the UE to determine that the UE does not recover from a data transfer stall within a specified amount of time. The UE may be in a first PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD. The memory and the one or more processors may be configured to transmit, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at  least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
In some aspects, an apparatus for wireless communication may include means for determining that the apparatus does not recover from a data transfer stall within a specified amount of time. The apparatus may be in a PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD. The apparatus may also include means for transmitting, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the apparatus does not recover from the data transfer stall within the specified amount of time.
Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification.
The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the  description may admit to other equally effective aspects. The same reference numbers in different drawings may identify the same or similar elements.
Fig. 1 is a diagram illustrating an example of a wireless network, in accordance with various aspects of the present disclosure.
Fig. 2 is a diagram illustrating an example of a base station in communication with a user equipment (UE) in a wireless network, in accordance with various aspects of the present disclosure.
Fig. 3 illustrates an example of a 5G architecture, in accordance with various aspects of the present disclosure.
Fig. 4 is a diagram illustrating an example of restoring data service in a standalone network, in accordance with various aspects of the present disclosure.
Fig. 5 is a diagram illustrating an example process performed, for example, by a UE, in accordance with various aspects of the present disclosure.
DETAILED DESCRIPTION
Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein, one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.
Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying  drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements” ) . These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.
It should be noted that while aspects may be described herein using terminology commonly associated with a 5G or NR radio access technologies (RAT) , aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and/or a RAT subsequent to 5G (e.g., 6G) .
Fig. 1 is a diagram illustrating an example of a wireless network 100, in accordance with various aspects of the present disclosure. The wireless network 100 may be or may include elements of a 5G (NR) network, an LTE network, and/or the like. The wireless network 100 may include a number of base stations 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A base station (BS) is an entity that communicates with user equipment (UEs) and may also be referred to as an NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.
A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in Fig. 1, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (e.g., three) cells. The terms “eNB” , “base station” , “NR BS” , “gNB” , “TRP” , “AP” , “node B” , “5G NB” , and “cell” may be used interchangeably herein.
In some aspects, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.
Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in Fig. 1, a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.
Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts) .
network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.
UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular  component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.
Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE) . UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like. In some aspects, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, electrically coupled, and/or the like.
In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular RAT and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.
In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another) . For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like) , a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.
As indicated above, Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.
Fig. 2 is a diagram illustrating an example 200 of a base station 110 in communication with a UE 120 in a wireless network 100, in accordance with various aspects of the present disclosure. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.
At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS (s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) , a demodulation reference signal (DMRS) , and/or the like) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively.
At UE 120, antennas 252a through 252r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain  received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , and/or the like. In some aspects, one or more components of UE 120 may be included in a housing 284.
Network controller 130 may include communication unit 294, controller/processor 290, and memory 292. Network controller 130 may include, for example, one or more devices in a core network. Network controller 130 may communicate with base station 110 via communication unit 294.
On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports that include RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , and transmitted to base station 110. In some aspects, the UE 120 includes a transceiver. The transceiver may include any combination of antenna (s) 252, modulators and/or demodulators 254, MIMO detector 256, receive processor 258, transmit processor 264, and/or TX MIMO processor 266. The transceiver may be used by a processor (e.g., controller/processor 280) and memory 282 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-5.
At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Base station 110 may include a scheduler 246 to schedule UEs 120 for downlink and/or uplink  communications. In some aspects, the base station 110 includes a transceiver. The transceiver may include any combination of antenna (s) 234, modulators and/or demodulators 232, MIMO detector 236, receive processor 238, transmit processor 220, and/or TX MIMO processor 230. The transceiver may be used by a processor (e.g., controller/processor 240) and memory 242 to perform aspects of any of the methods described herein, for example, as described with reference to Figs. 3-5.
Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform one or more techniques associated with restoring data service in a standalone (SA) network, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform or direct operations of, for example, process 500 of Fig. 5 and/or other processes as described herein.  Memories  242 and 282 may store data and program codes for base station 110 and UE 120, respectively. In some aspects, memory 242 and/or memory 282 may include a non-transitory computer-readable medium storing one or more instructions (e.g., code, program code, and/or the like) for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, interpreting, and/or the like) by one or more processors of the base station 110 and/or the UE 120, may cause the one or more processors, the UE 120, and/or the base station 110 to perform or direct operations of, for example, process 500 of Fig. 5 and/or other processes as described herein. In some aspects, executing instructions may include running the instructions, converting the instructions, compiling the instructions, interpreting the instructions, and/or the like.
In some aspects, UE 120 may include means for determining that the UE does not recover from a data transfer stall within a specified amount of time, where the UE is in a first protocol data unit (PDU) session, in an NR standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) , means for transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time, and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with Fig. 2, such as  controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.
While blocks in Fig. 2 are illustrated as distinct components, the functions described above with respect to the blocks may be implemented in a single hardware, software, or combination component or in various combinations of components. For example, the functions described with respect to the transmit processor 264, the receive processor 258, and/or the TX MIMO processor 266 may be performed by or under the control of processor 280.
As indicated above, Fig. 2 is provided as an example. Other examples may differ from what is described with regard to Fig. 2.
Fig. 3 illustrates an example 300 of a 5G architecture, in accordance with various aspects of the present disclosure.
The 5G architecture may include a next generation radio access network (NG-RAN) , which may include one or more base stations, such as base station 110, that communicate with a UE, such as UE 120, over a Uu interface. The Uu interface is a radio interface between the UE and the NG-RAN. The 5G architecture may include a core network (5GC) that provides communications between the NG-RAN and the outside world, including devices that may act as system information servers, such as mobile network operator servers, cloud servers, third-party servers, servers of companies that may provide data and services to the UE through applications on the UE, and/or the like.
The 5GC may include a unified data management (UDM) entity that makes relevant data available to an access and mobility management function (AMF) entity and a session management function (SMF) entity. The AMF entity manages UE network registration, manages mobility, maintains a non-access stratum (NAS) signaling connection with the UE, and manages a registration procedure of the UE with a network. The SMF entity manages sessions and allocates IP addresses to the UE. The 5GC includes a user plane function (UPF) entity that manages user traffic to and from the UE through the NG-RAN and enforces a quality of service (QoS) . The 5GC includes a policy and control function (PCF) entity that implements charging rules, implements flow control rules, manages traffic priority, and manages a QoS for user subscription services. The 5GC may include a unified data repository (UDR) entity that stores structured data for exposure to network functions and a network exposure function (NEF) entity that securely exposes services and capabilities provided by 3GPP  network functions. The 5GC also includes an application function (AF) entity that supports application functionality, influences traffic routing, and interacts with the PCF entity.
While 4G Long Term Evolution (LTE) uses evolved packet system (EPS) bearers, each assigned an EPS bearer identifier (ID) , 5G uses QoS flows, each identified by a QoS flow ID (QFI) . The QoS flow is where policy and charging are enforced. All traffic within the same QoS flow may receive the same treatment. In the 5GC, there is a single user plane network function -the UPF -for transport of data between a base station (e.g., gNB) and the 5GC. Each QoS flow on an N3 interface may be mapped to a single general packet radio service (GPRS) tunneling protocol (GTP) tunnel for the user plane (GTP-U) . The gNB may map individual QoS flows to one more dedicated radio bearers (DRBs) . A PDU session may contain multiple QoS flows and several DRBs, but only a single N3 GTP-U tunnel. A DRB may transport one or more QoS flows. In sum, these entities permit user data traffic or other types of information to be transmitted on a user plane.
UE policies for 5G include a UE route selection policy (URSP) and an access network discovery and selection policy (ANDSP) . The UE policies may be delivered to the UE by the PCF, which interfaces to both the AMF and the SMF. The URSP enables the UE to determine how a certain application should be handled in the context of an existing or new PDU session. A PDU session defines the association between the UE and the a network that provides a PDU connectivity service. Each PDU session may be identified by a PDU session ID, and includes one or more QoS flows and QoS rules.
The URSP may be defined as a set of one or more URSP rules. Each URSP rule may include a precedence value of the URSP rule as compared to other URSP rules, a traffic descriptor, and one or more RSDs. Each RSD may include one or more parameters such as a precedence value, a PDU session type, a session and service continuity mode, network slice selection assistance information, a data network name, a multi-access preference, an offload indication, and/or the like.
As indicated above, Fig. 3 is provided as an example. Other examples may differ from what is described with regard to Fig. 3.
Once the UE is registered with an NG-RAN of an SA network, the UE may establish a PDU session. The UE may transmit a PDU session establishment request based at least in part on one or more parameters specified by a first RSD. However, the UE may experience a data transfer stall due to a temporary or permanent network issue.  The UE may determine there is a data transfer stall if an expected data transfer does not occur when expected or if data transfers stop for a certain period of time. The UE may not recover for some time from the data transfer stall, providing a user of the UE a bad experience. The UE may waste time, power, and processing resources waiting for the data transfer stall to recover, and the data transfer stall may never recover.
According to various aspects described herein, the UE may determine that the data transfer stall has not recovered within a specified amount of time, release the PDU session, and establish a new PDU session with the next RSD. In this way, the UE may save time, power, and processing resources instead of waiting for a data transfer stall recovery that may never come.
Fig. 4 is a diagram illustrating an example 400 of restoring data service in an SA network, in accordance with various aspects of the present disclosure. Fig. 4 illustrates a UE (e.g., a UE 120 depicted in Figs. 1 and 2, the UE in Fig. 3) that is registered to an NG-RAN of an SA network. The UE may communicate with an AMF of the SA network, where the AMF is associated with one or more UPFs (e.g., UPF1, UPF2) .
Once the UE is registered with the SA network, the UE may establish a PDU session. As shown by reference number 405, the UE may transmit a PDU session establishment request based at least in part on one or more parameters specified by a first RSD (e.g., RSD1) . RSD1 may map to UPF1, and as shown by reference number 410, the AMF may select UPF1. As shown by reference number 415, the UE may receive a PDU session establishment accept message. However, the UE may experience a data transfer stall due to a temporary or permanent network issue.
As shown by reference number 420, the UE may trigger a data transfer stall timer when a data transfer stall is detected (e.g., data transfers stop for a threshold amount of stall time) . The timer may be set to an amount of time that is based at least in part on a type of service (e.g., data call, streaming application, and/or the like) associated with the data transfer stall. For example, the amount of time may be shorter for more time-sensitive applications or for applications that may be impacted more than other applications. The UE may keep checking the timer if no data transfers occur or if not all of the expected data transfers occur. As shown by reference number 425, the UE may determine that the data transfer stall has not recovered before expiration of the timer, or within a specified amount of time.
As shown by reference number 430, the UE may transmit a PDU session release request to the AMF for the PDU session (that uses RSD1) based at least in part on determining that the data transfer stall has not recovered before expiration of the timer or within the specified amount of time. As shown by reference number 435, the UE may transmit a PDU session establishment request that is based at least in part on one or more parameters specified by RSD2, which maps to UPF2. RSD2 may be the next RSD in a sequence of RSDs, which may be ordered from highest precedence to lowest precedence. As shown by reference number 440, the AMF may select UPF2, which is mapped to RSD2. The UE may receive a PDU session establishment accept message, as shown by reference number 445. The UE may have data service restored, as shown by reference number 450.
In some aspects, if a data transfer stall occurs again for the PDU session that uses RSD2, the next RSD (e.g., RSD3) in the sequence of RSDs may be used to establish the next PDU session. The quantity of RSDs in the sequence of RSDs may be based at least in part on an operator configuration. For example, there may be 8 RSDs in the sequence of RSDs. In some aspects, there may be greater or fewer RSDs. The UE may progress through the sequence of RSDs, as necessary, without waiting too long for a data transfer stall to recover for a first RSD.
As indicated above, Fig. 4 is provided as an example. Other examples may differ from what is described with regard to Fig. 4.
Fig. 5 is a diagram illustrating an example process 500 performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process 500 is an example where the UE (e.g., a UE 120 depicted in Figs. 1 and 2, the UE depicted in Figs. 3 and 4, and/or the like) performs operations associated with restoring data service in an SA network.
As shown in Fig. 5, in some aspects, process 500 may include determining that the UE does not recover from a data transfer stall within a specified amount of time (block 510) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may determine that the UE does not recover from a data transfer stall within a specified amount of time, as described above. In some aspects, the UE is in a first PDU session, in an NR SA network, that was established based at least in part on one or more parameters specified by a first RSD.
As further shown in Fig. 5, in some aspects, process 500 may include transmitting, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time (block 520) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may transmit, to an AMF of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time, as described above.
Process 500 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.
In a first aspect, the second RSD is a next RSD in a sequence of RSDs.
In a second aspect, alone or in combination with the first aspect, the first RSD has a higher precedence than the second RSD.
In a third aspect, alone or in combination with one or more of the first and second aspects, the first RSD is associated with a first UPF, and the second RSD is associated with a second UPF.
In a fourth aspect, alone or in combination with one or more of the first through third aspects, process 500 includes transmitting a PDU session release request for the first PDU session.
In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, transmitting the PDU session establishment request includes transmitting the PDU session establishment request based at least in part on the transmitting the PDU session release request.
In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 500 includes starting a timer based at least in part on the data transfer stall, and transmitting, to the AMF, a PDU session release request for the first PDU session based at least in part on expiration of the timer.
In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process 500 includes transmitting, to the AMF, a PDU session establishment request with one or more parameters specified by a third RSD, based at least in part on a determination that the UE does not recover from the data transfer stall  with the PDU session establishment request with the one or more parameters specified by the second RSD.
In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process 500 includes configuring the specified amount of time based at least in part on a type of service associated with the data transfer stall.
Although Fig. 5 shows example blocks of process 500, in some aspects, process 500 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 5. Additionally, or alternatively, two or more of the blocks of process 500 may be performed in parallel.
The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.
As used herein, the term “component” is intended to be broadly construed as hardware, software, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, software, and/or a combination of hardware and software. Software is to be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and/or the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.
As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.
It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware, software, and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code-it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.
Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .
No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items and may be used interchangeably with “one or more. ” Further, as used herein, the article “the” is intended to include one or more items referenced in connection with the article “the” and may be used interchangeably with “the one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Also, as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and/or, ” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of” ) .

Claims (12)

  1. A method of wireless communication performed by a user equipment (UE) , comprising:
    determining that the UE does not recover from a data transfer stall within a specified amount of time, wherein the UE is in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) ; and
    transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
  2. The method of claim 1, wherein the second RSD is a next RSD in a sequence of RSDs.
  3. The method of claim 1, wherein the first RSD has a higher precedence than the second RSD.
  4. The method of claim 1, wherein the first RSD is associated with a first user plane function (UPF) , and the second RSD is associated with a second UPF.
  5. The method of claim 1, further comprising transmitting a PDU session release request for the first PDU session.
  6. The method of claim 5, wherein transmitting the PDU session establishment request includes transmitting the PDU session establishment request based at least in part on the transmitting the PDU session release request.
  7. The method of claim 1, further comprising:
     starting a timer based at least in part on the data transfer stall; and
     transmitting, to the AMF, a PDU session release request for the first PDU session based at least in part on expiration of the timer.
  8. The method of claim 1, further comprising transmitting, to the AMF, a PDU session establishment request with one or more parameters specified by a third RSD, based at least in part on a determination that the UE does not recover from the data transfer stall with the PDU session establishment request with the one or more parameters specified by the second RSD.
  9. The method of claim 1, further comprising configuring the specified amount of time based at least in part on a type of service associated with the data transfer stall.
  10. A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions, when executed by one or more processors of a user equipment (UE) , cause the UE to:
    determine that the UE does not recover from a data transfer stall within a specified amount of time, wherein the UE is in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) ; and
    transmit, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
  11. A user equipment (UE) for wireless communication, comprising:
    a memory; and
    one or more processors operatively coupled to the memory, the memory including instructions executable by the one or more processors to cause the UE to:
    determine that the UE does not recover from a data transfer stall within a specified amount of time, wherein the UE is in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) ; and
    transmit, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more  parameters specified by a second RSD, based at least in part on the determining that the UE does not recover from the data transfer stall within the specified amount of time.
  12. An apparatus for wireless communication, comprising:
    means for determining that the apparatus does not recover from a data transfer stall within a specified amount of time, wherein the apparatus is in a first protocol data unit (PDU) session, in a New Radio (NR) standalone (SA) network, that was established based at least in part on one or more parameters specified by a first route selection descriptor (RSD) ; and
    means for transmitting, to an access and mobility management function (AMF) of the NR SA network, a PDU session establishment request with one or more parameters specified by a second RSD, based at least in part on the determining that the apparatus does not recover from the data transfer stall within the specified amount of time.
PCT/CN2020/093310 2020-05-29 2020-05-29 Restoration of data service in a standalone network WO2021237690A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/093310 WO2021237690A1 (en) 2020-05-29 2020-05-29 Restoration of data service in a standalone network

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/093310 WO2021237690A1 (en) 2020-05-29 2020-05-29 Restoration of data service in a standalone network

Publications (1)

Publication Number Publication Date
WO2021237690A1 true WO2021237690A1 (en) 2021-12-02

Family

ID=78745440

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/093310 WO2021237690A1 (en) 2020-05-29 2020-05-29 Restoration of data service in a standalone network

Country Status (1)

Country Link
WO (1) WO2021237690A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018141269A1 (en) * 2017-02-06 2018-08-09 Huawei Technologies Co., Ltd. Network registration and network slice selection system and method
WO2019164439A1 (en) * 2018-02-20 2019-08-29 Telefonaktiebolaget Lm Ericsson (Publ) Small data user plane transmission for cellular internet of things (ciot)
CN110351186A (en) * 2018-04-02 2019-10-18 苹果公司 The use of multi-path transmission control protocol agency in cellular networks

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018141269A1 (en) * 2017-02-06 2018-08-09 Huawei Technologies Co., Ltd. Network registration and network slice selection system and method
WO2019164439A1 (en) * 2018-02-20 2019-08-29 Telefonaktiebolaget Lm Ericsson (Publ) Small data user plane transmission for cellular internet of things (ciot)
CN110351186A (en) * 2018-04-02 2019-10-18 苹果公司 The use of multi-path transmission control protocol agency in cellular networks

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Policy and charging control framework for the 5G System (5GS); Stage 2 (Release 16)", 3GPP STANDARD; TECHNICAL SPECIFICATION; 3GPP TS 23.503, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. SA WG2, no. V16.4.1, 6 April 2020 (2020-04-06), pages 1 - 115, XP051893851 *

Similar Documents

Publication Publication Date Title
US11564280B2 (en) User equipment to network relay
US11672031B2 (en) Managing a backhaul configuration in a wireless multi-hop network
US11876777B2 (en) Management of identifiers in an integrated access and backhaul network
US11540211B2 (en) Techniques for integrated access and backhaul capability indication
WO2022036490A1 (en) Modifying a quality of service flow packet delay budget
WO2021243690A1 (en) Public land mobile network search after protocol data unit rejection
US20230082718A1 (en) Protocol data unit session management
US11071152B2 (en) Access barring and radio resource control connection in new radio to long-term evolution voice fallback
WO2021237690A1 (en) Restoration of data service in a standalone network
WO2021232399A1 (en) Restoration of data service in a standalone network
WO2021120032A1 (en) Fast connection release after paging response
WO2021243622A1 (en) Associating application identifiers with network slices
WO2021253394A1 (en) Public land mobile network search for user equipment route selection policy rule
WO2021212452A1 (en) Restoration of data connectivity upon bearer removal after handover
WO2022073153A1 (en) Dual audio channels over dual quality of service flows
WO2021207917A1 (en) Restoration of data connectivity after failure by rrc connection releases in non-standalone network
WO2021208051A1 (en) Restoration of data connectivity after failure by rrc connection releases in non-standalone network
WO2021212395A1 (en) Restoration of data connectivity after data call failure in non-standalone network
WO2021232331A1 (en) Restoration of new radio data service for dual subscriber identity modules
WO2021212401A1 (en) Restoration of data connectivity
WO2021223202A1 (en) Restoration of data service with dual subscriber identity modules
WO2022056701A1 (en) Optimized protocol data unit session establishment procedure
WO2021232179A1 (en) Restoration of vehicle to everything service
US20210377789A1 (en) Non-access stratum congestion indications
WO2021207918A1 (en) Restoration of data connectivity after data call failure in non-standalone network

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20938321

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20938321

Country of ref document: EP

Kind code of ref document: A1