WO2024093430A1

WO2024093430A1 - Data handling based on pdu set configuration

Info

Publication number: WO2024093430A1
Application number: PCT/CN2023/112766
Authority: WO
Inventors: Xiaoying Xu; Mingzeng Dai; Lianhai WU; Haiyan Luo
Original assignee: Lenovo (Beijing) Limited
Priority date: 2023-08-11
Filing date: 2023-08-11
Publication date: 2024-05-10

Abstract

Various aspects of the present disclosure relate to data handling based on a protocol data unit (PDU) set configuration. In one aspect of the solution of the present disclosure, a user equipment receives a configuration from a network device, and the configuration is associated with a PDU set for a data radio bearer (DRB). The user equipment receives a PDU in a PDU set from an upper layer of the user equipment. Based on whether information of the PDU set for the PDU is identified by the user equipment, the user equipment starts a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU. In this way, it is determined that which discard timer may be started and when to start the discard timer. Therefore, the performance of communication is improved.

Description

DATA HANDLING BASED ON PDU SET CONFIGURATION

TECHNICAL FIELD

The present disclosure relates to wireless communications, and more specifically to data handling based on protocol data unit (PDU) set configuration.

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication devices, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

Extended reality (XR) , including augmented reality (AR) and virtual reality (VR) , as well as cloud gaming (CG) , presents a new promising category of connected devices, applications, and services. XR applications typically requires high throughput and low latency, and have a big packet size, variable data packet size and arrival jitter. However, there are some issues for packet handling to be addressed.

SUMMARY

The present disclosure relates to methods, apparatuses, and systems that support data handling based on PDU set configuration.

Some implementations of the method and devices described herein may include, receiving, via the transceiver from a network device, a configuration associated with a protocol data unit (PDU) set for a data radio bearer (DRB) ; receiving a PDU in a PDU set from an upper layer of the user equipment; and starting a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment. In this way, it is determined that which discard timer may be started and when to start the discard timer. Therefore, the performance of communication is improved.

Some implementations of the method and devices described herein may include, starting the discard timer associated with the PDCP SDU may comprise: based on determining that the information of the PDU set for the PDU is not identified by the user equipment, starting one of the following: a first discard timer, which is not corresponding to a PDU set importance (PSI) level; a second discard timer corresponding to a PSI level.

Some implementations of the method and devices described herein may include, starting the discard timer associated with the PDCP SDU may comprise: based on determining that the information of the PDU set for the PDU is not identified by the user equipment, starting one of the following: a first discard timer, which is not corresponding to a PDU set importance (PSI) level; a second discard timer corresponding to a default PSI level.

Some implementations of the method and devices described herein may include, starting the discard timer associated with the PDCP SDU may comprise: based on determining that the PDU set for the PDU is not a complete PDU set, starting one of the following: a first discard timer, which is not corresponding to a PDU set importance (PSI) level; a second discard timer corresponding to a default PSI level.

Some implementations of the method and devices described herein may include, based on determining that the information of the PDU set for the PDU is not identified by the user equipment, considering the PDU as a PDU set.

Some implementations of the method and devices described herein may include, based on determining that the information of the PDU set for the PDU is not identified by the user equipment, considering the PSI of the PDU as a default PSI.

Some implementations of the method and devices described herein may include, starting the discard timer associated with the PDCP SDU may comprise: based on determining that the information of the PDU set for the PDU is identified by the user equipment and the PDU set of the PDU is not a complete PDU set, starting one of the following: a first discard timer, which is not corresponding to a PDU set importance (PSI) level; or a second discard timer corresponding to a default PSI level.

Some implementations of the method and devices described herein may include, ignoring the first discard timer if the PDCP SDU is a PDCP SDU of a second PDU set; or starting a second discard timer corresponding to a PSI level of the second PDU set if the PDCP SDU is a PDCP SDU of the second PDU set.

Some implementations of the method and devices described herein may include, the configuration associated with a PDU set for a DRB is a first configuration, starting the discard timer associated with the PDCP SDU may comprise: receiving, from the network device, a second configuration to indicate which discard timer is to be started for a PDCP SDU if PDU set information of the PDCP SDU is not identified or the PDU set of the PDCP SDU is not a complete PDU set; and starting a discard timer indicated according to the second configuration based on determining that the information of the PDU set for the PDCP SDU is not identified by the user equipment or the PDU set of the PDCP PDU is not a complete PDU set.

Some implementations of the method and devices described herein may include, starting the discard timer associated with the PDCP SDU may comprise: starting a second discard timer associated with the PDCP SDU based on determining that the information of the PDU set for the PDU is identified, wherein a PSI level of the second discard timer is the PSI level of the PDU set for the PDU.

Some implementations of the method and devices described herein may include, determining whether the PDCP SDU is starting data of the first PDU set or the PDU set of the PDCP PDU is not a complete PDU set; based on determining that the PDCP SDU is the starting data of the first PDU set or the PDU set of the PDCP PDU is a complete PDU set, starting a second discard timer corresponding to which a PSI level is the PSI of the first PDU set for the PDU; or based on determining that the PDCP SDU is not the starting data of the first PDU set or the PDU set of the PDCP PDU is not a complete PDU set, not starting a second discard timer until a first PDU of the second PDU set is identified.

Some implementations of the method and devices described herein may include, the discard timer expiring, and the user equipment further based on determining that the information of the PDU set for the PDU is identified, determining whether the PDCP SDU is starting data of the PDU set; based on determining that the PDCP SDU is the starting data of the PDU set, discarding all PDCP SDUs in the PDU set, wherein the PDCP SDU corresponding to a PDU in the PDU set.

Some implementations of the method and devices described herein may include, the discard timer expiring, and the user equipment further based on determining that the information of the PDU set for the PDU is identified, and based on determining that not all the information of the PDU set for the PDUs in the PDU set is identified, discarding the PDCP SDU along with a PDU corresponding to the PDCP SDU.

Some implementations of the method and devices described herein may include, the discard timer expiring, the user equipment further based on determining that the information of the PDU set for the PDU is identified, and based on determining that not all the information of the PDU set for the PDUs in the PDU set is identified, discarding one or more PDCP SDUs, for which the information of the PDU set is identified, along with one or more PDUs corresponding to the one or more PDCP SDUs.

Some implementations of the method and devices described herein may include, the discard timer expiring, and the user equipment further receiving, from the network device, an indication to discard a PDU set; based on determining that the information of the PDU set for the PDU is identified, determining whether the PDCP SDU is starting data of the PDU set; based on determining that the PDCP SDU is the starting data of the PDU set, discarding the PDCP SDUs in the PDU set, wherein the PDCP SDU corresponding to a PDU in the PDU set; and based on determining that the PDCP SDU is not the starting data of the PDU set, discarding the PDCP SDU along with one or more PDCP SDUs in the PDU set, wherein the information of the PDU set of the one or more PDCP SDUs is identified.

Some implementations of the method and devices described herein may include, the user equipment further based on determining that the information of the PDU set for the PDU is not identified, transmitting, to the network device, a first report of remaining discard time comprising a shortest value of discard time of one or more PDCP SDUs in the PDU set.

Some implementations of the method and devices described herein may include, the user equipment further based on determining that the information of the PDU set for the PDU is not identified, transmitting, to the network device, a report indicating that the information of the PDU set is not identified.

In some implementations of the method and devices described herein, the information of the PDU set may comprise at least one of the following: a sequence number of the PDU set; an indication of end PDU of the PDU set; a sequence number of a PDU within the PDU set; a size of the PDU set in bytes; or PDU set importance (PSI) level of the PDU set.

In some implementations of the method and devices described herein, the discard timer may comprise one of the following: a first discard timer, which is not corresponding to a PDU set importance (PSI) level or a second discard timer corresponding to a PSI level.

In some implementations of the method and devices described herein, the second discard timer may be one of multiple discard timers, and the multiple discard timers are corresponding to one PSI.

In some implementations of the method and devices described herein, the first discard timer may be associated with a previous PDCP SDU of the PDCP SDU.

In some implementations of the method and devices described herein, the information of the PDU set is not identified for all the PDUs in the PDU set of the PDCP SDU by the UE may comprise: the information of the PDU set for the starting data in the PDU set is not identified or the PDU set for the PDCP SDU is not a complete PDU set.

In some implementations of the method and devices described herein, the information of the PDU set for the first PDU in the second PDU set may be identified by the user equipment; the PDCP SDU may be a starting data of the second PDU set; the discard timer may be the first discard timer, the PDU set is a first PDU set, and the second PDU set follows the first PDU set; the second PDU set is a complete PDU set; the first PDU set is not a complete PDU set; or any combination of two or more of the above-mentioned items.

Some implementations of the method and devices described herein may further include determining to map a quality of service (QoS) flow from a first data radio bearer (DRB) to a second DRB; and routing a protocol data unit (PDU) of the QoS flow to the second DRB based on determining that PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment. In this way, it is defined that the rule for routing PDU to different DRBs. Therefore, the performance of communication is improved.

Some implementations of the method and devices described herein may include, routing a PDU of the QoS flow to the first DRB based on determining that the PDU set information for the PDU not identified by the user equipment; routing a PDU of the QoS flow to the first DRB based on determining that the PDU set of the PDU is not a complete PDU set by the user equipment; or routing a PDU of the QoS flow to the first DRB based on determining that the PDU set information for a first PDU of the PDU set of the PDU is not identified by the user equipment.

Some implementations of the method and devices described herein may include, routing a PDU of the QoS flow to the first DRB until a first PDU of a PDU set is identified by the user equipment or the PDU set of the PDU is a complete PDU set.

Some implementations of the method and devices described herein may include, generating an end mark control PDU based on determining that the PDU set information for a first PDU of the PDU set is identified by the user equipment; generating an end mark control PDU based on determining that the PDU set of a PDU is a complete PDU set; or generating an end mark control PDU based on determining that the PDU set information for a PDU of the QoS flow is identified by the user equipment.

Some implementations of the method and devices described herein may include, transmitting the end mark on first DRB after completing transmission of data on the first DRB.

Some implementations of the method and devices described herein may include, determining to map the QoS flow from the first DRB to the second DRB may comprise: receiving, from a network device, a reconfiguration message for mapping the QoS flow from the first DRB to the second DRB; and determining to map the QoS flow from the first DRB to the second DRB based on the reconfiguration message.

In some implementations of the method and devices described herein, the first DRB may be not configured with PDU set handling, and the second DRB may be configured with PDU set handling.

In some implementations of the method and devices described herein, the first PDU may be the starting data in the PDU set or the PDU set of the first PDU is a complete PDU set.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an example of a wireless communications system that supports sensing data exchange in accordance with aspects of the present disclosure.

FIG. 1B illustrates an example of a data radio bearer (DRB) reconfigured with protocol data unit (PDU) set handling parameter associated with aspects of the present disclosure.

FIG. 2 illustrates a flowchart of a method that supports data handling based o n PDU set configuration in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example of PDU set identifying trigger procedure in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of packet data convergence protocol (PDCP) discard timer configuration of a DRB in accordance with aspects of the present disclosure.

FIG. 5 illustrates an example of PDU set information can be identified in accordance with aspects of the present disclosure.

FIG. 6 illustrates a flowchart of a method that supports data handling based o n PDU set configuration in accordance with aspects of the present disclosure.

FIG. 7 illustrates an example of quality of service (QoS) flow-DRB remapping procedure in accordance with aspects of the present disclosure.

FIG. 8 illustrates an example of device that support data handling based on P DU set configuration in accordance with aspects of the present disclosure.

FIG. 9 illustrates an example of processor that support data handling based o n PDU set configuration in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Principles of the present disclosure will now be described with reference to some embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein may be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

References in the present disclosure to “one embodiment, ” “an example embodiment, ” “an embodiment, ” “some embodiments, ” and the like indicate that the embodiment (s) described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment (s) . Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

It shall be understood that although the terms “first” and “second” or the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, a first element could also be termed as a second element, and similarly, a second element could also be termed as a first element, without departing from the scope of embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined by “and” or “or” , mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as, 5G new radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) , and so on. Further, the communications between a user equipment and a network device in the communication network may be performed according to any suitable generation communication protocols, including but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will also be future type communication technologies and systems in which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned systems.

As used herein, the term “network device” generally refers to a node in a communication network via which a user equipment can access the communication network and receive services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , a radio access network (RAN) node, an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , an infrastructure device for a V2X (vehicle-to-everything) communication, a transmission and reception point (TRP) , a reception point (RP) , a remote radio head (RRH) , a relay, an integrated access and backhaul (IAB) node, a low power node such as a femto BS, a pico BS, and so forth, depending on the applied terminology and technology. The network device may further refer to a network function (NF) in the core network, for example, a SMF, an AMF, a PCF, a UPF or devices with same function in future network architectures, and so forth.

As used herein, the term “user equipment (UE) ” generally refers to any end device that may be capable of wireless communications. By way of example rather than a limitation, a user equipment may also be referred to as a communication device, a terminal device, an end user device, a subscriber station (SS) , an unmanned aerial vehicle (UAV) , a portable subscriber station, a mobile station (MS) , or an access terminal (AT) . The user equipment may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet, a wearable user equipment, a personal digital assistant (PDA) , a portable computer, a desktop computer, an image capture user equipment such as a digital camera, a gaming user equipment, a music storage and playback appliance, a vehicle-mounted wireless user equipment, a wireless endpoint, a mobile station, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , a USB dongle, a smart device, wireless customer-premises equipment (CPE) , an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device (for example, a remote surgery device) , an industrial device (for example, a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms: “user equipment, ” “communication device, ” “terminal, ” “user equipment” and “UE, ” may be used interchangeably.

As used herein, the term “PDU set” refers to one or more PDUs carrying the payload of one unit of information generated at the application level (e.g. frame (s) or video slice (s) etc. for XR services) .

As used herein, the term “PDU set information” may refers to information of the PDU, and the information of the PDU set may comprise: PDU set sequence number, indication of end PDU of the PDU set, PDU sequence number within a PDU set, PDU set size in bytes, PDU set importance (PSI) . The PSI identifies the relative importance of a PDU set compared to other PDU sets within the same QoS flow.

FIG. 1A illustrates an example of a wireless communications system 100A that supports data handling based on PDU set configuration in accordance with aspects of the present disclosure. The wireless communications system 100A may include one or more network entities 102 (also referred to as network equipment (NE) ) , one or more UEs 104, a core network 106, and a packet data network 108. The wireless communications system 100A may support various radio access technologies. In some implementations, the wireless communications system 100A may be a 4G network, such as an LTE network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100A may be a 5G network, such as an NR network. In other implementations, the wireless communications system 100A may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20. The wireless communications system 100A may support radio access technologies beyond 5G. Additionally, the wireless communications system 100A may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more network entities 102 may be dispersed throughout a geographic region to form the wireless communications system 100A. One or more of the network entities 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a radio access network (RAN) , a base transceiver station, an access point, a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. A network entity 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, a network entity 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

A network entity 102 may provide a geographic coverage area 112 for which the network entity 102 may support services (e.g., voice, video, packet data, messaging, broadcast, etc. ) for one or more UEs 104 within the geographic coverage area 112. For example, a network entity 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, a network entity 102 may be moveable, for example, a satellite associated with a non-terrestrial network. In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas 112 may be associated with different network entities 102. Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The one or more UEs 104 may be dispersed throughout a geographic region of the wireless communications system 100A. A UE 104 may include or may be referred to as a mobile device, a wireless device, a remote device, a remote unit, a handheld device, or a subscriber device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (MTC) device, among other examples. In some implementations, a UE 104 may be stationary in the wireless communications system 100A. In some other implementations, a UE 104 may be mobile in the wireless communications system 100A.

The one or more UEs 104 may be devices in different forms or having different capabilities. Some examples of UEs 104 are illustrated in FIG. 1. A UE 104 may be capable of communicating with various types of devices, such as the network entities 102, other UEs 104, or network equipment (e.g., the core network 106, the packet data network 108, a relay device, an integrated access and backhaul (IAB) node, or another network equipment) , as shown in FIG. 1. Additionally, or alternatively, a UE 104 may support communication with other network entities 102 or UEs 104, which may act as relays in the wireless communications system 100A.

A UE 104 may also be able to support wireless communication directly with other UEs 104 over a communication link 114. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

A network entity 102 may support communications with the core network 106, or with another network entity 102, or both. For example, a network entity 102 may interface with the core network 106 through one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the network entities 102 may communicate with each other directly (e.g., between the network entities 102) . In some other implementations, the network entities 102 may communicate with each other or indirectly (e.g., via the core network 106) . In some implementations, one or more network entities 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

In some implementations, a network entity 102 may be configured in a disaggregated architecture, which may be configured to utilize a protocol stack physically or logically distributed among two or more network entities 102, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance) , or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN) ) . For example, a network entity 102 may include one or more of a central unit (CU) , a distributed unit (DU) , a radio unit (RU) , a RAN Intelligent Controller (RIC) (e.g., a Near-Real Time RIC (Near-RT RIC) , a Non-Real Time RIC (Non-RT RIC) ) , a Service Management and Orchestration (SMO) system, or any combination thereof.

An RU may also be referred to as a radio head, a smart radio head, a remote radio head (RRH) , a remote radio unit (RRU) , or a transmission reception point (TRP) . One or more components of the network entities 102 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 102 may be located in distributed locations (e.g., separate physical locations) . In some implementations, one or more network entities 102 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .

Split of functionality between a CU, a DU, and an RU may be flexible and may support different functionalities depending upon which functions (e.g., network layer functions, protocol layer functions, baseband functions, radio frequency functions, and any combinations thereof) are performed at a CU, a DU, or an RU. For example, a functional split of a protocol stack may be employed between a CU and a DU such that the CU may support one or more layers of the protocol stack and the DU may support one or more different layers of the protocol stack. In some implementations, the CU may host upper protocol layer (e.g., a layer 3 (L3) , a layer 2 (L2) ) functionality and signaling (e.g., Radio Resource Control (RRC) , service data adaption protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU may be connected to one or more DUsor RUs, and the one or more DUs or RUs may host lower protocol layers, such as a layer 1 (L1) (e.g., physical (PHY) layer) or an L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160.

Additionally, or alternatively, a functional split of the protocol stack may be employed between a DU and an RU such that the DU may support one or more layers of the protocol stack and the RU may support one or more different layers of the protocol stack. The DU may support one or multiple different cells (e.g., via one or more RUs) . In some implementations, a functional split between a CU and a DU, or between a DU and an RU may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU, a DU, or an RU, while other functions of the protocol layer are performed by a different one of the CU, the DU, or the RU) .

A CU may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU may be connected to one or more DUs via a midhaul communication link (e.g., F1, F1-c, F1-u) , and a DU may be connected to one or more RUs via a fronthaul communication link (e.g., open fronthaul (FH) interface) . In some implementations, a midhaul communication link or a fronthaul communication link may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 102 that are in communication via such communication links.

The core network 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The core network 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management (e.g., data bearers, signal bearers, etc. ) for the one or more UEs 104 served by the one or more network entities 102 associated with the core network 106.

The core network 106 may communicate with the packet data network 108 over one or more backhaul links 116 (e.g., via an S1, N2, N2, or another network interface) . The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the core network 106 via a network entity 102. The core network 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the core network 106 (e.g., one or more network functions of the core network 106) .

In the wireless communications system 100A, the network entities 102 and the UEs 104 may use resources of the wireless communications system 100A (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the network entities 102 and the UEs 104 may support different resource structures. For example, the network entities 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the network entities 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the network entities 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The network entities 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100A, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100A. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100A, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100A may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz –7.125 GHz) , FR2 (24.25 GHz –52.6 GHz) , FR3 (7.125 GHz –24.25 GHz) , FR4 (52.6 GHz –114.25 GHz) , FR4a or FR4-1 (52.6 GHz –71 GHz) , and FR5 (114.25 GHz –300 GHz) . In some implementations, the network entities 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the network entities 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the network entities 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

FIG. 1B illustrates an example of a DRB reconfigured with PDU set handling parameter (e.g., PDU-set discard indicator, PSI discard timer (s) , PDU-set delay report configuration) associated with aspects of the present disclosure. As shown in FIG. 1B, the user equipment may receive a RRC reconfiguration for a DRB, e.g., with PDU set importance based discard timer, PDU set discard indicator after receiving packet 1. PDU set information of packet 1, packet 2, packet 3 and packet 4 is not identified by UE, and PDU set information of packet 5 and packet 6 is identified by UE.

If UE is configured or reconfigured from not supporting PDU set handling to supporting PDU set handling (e.g., PDU-set discard based on discard timers, PDU-set delay report) for data and if there’s data (e.g., packets 1, 2, 3, 4) without PDU set information identified by UE (maybe UE has not identified PDU set information without triggering from AS or NAS layer or without being provided by APP layer) . In an example, after the UE handovers from a source NG-RAN not supporting PDU set handling to a target NG-RAN supporting PDU set handling, the UE is reconfigured a DRB from without PDU set handling to with PDU set handling. In another example, the UE is reconfigured a DRB from without PDU set handling to with PDU set handling in a serving cell according to NG-RAN policy. In yet another example, the UE is configured or reconfigured with a DRB to supporting PDU set handling for a QoS flow, however the PDU set information is not identified by UE, e.g., UE cannot or does not start identifying the PDU set information.

Therefore, there are some issues regarding how to perform the discard operation, and delay report procedure. It should be defined that the discard operation, e.g., consider which discard timer to use for the data without PDU set information identified by UE and how to perform discarding based on the PDU set discard indication, how to transmit the delay report based on the remaining discard timer.

In view of the above discussions, embodiments of the present disclosure provide a solution for data handling based on PDU set configuration. In one aspect of the solution of the present disclosure, a user equipment receives a configuration from a network device, and the configuration is associated with a PDU set for a DRB. The user equipment receives a PDU in a PDU set from an upper layer of the user equipment. Based on whether information of the PDU set for the PDU is identified by the user equipment, the user equipment starts a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU. In other aspect of the solution of the present disclosure, a user equipment determines to map a QoS flow from a first DRB to a second DRB. Based on determining that PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment, the user equipment routes a PDU set of the QoS flow to the second DRB. In this way, it is determined that which discard timer may be started and when to start the discard timer and the rule for routing PDU to different DRBs. Therefore, the performance of communication is improved. Principles and implementations of embodiments of the present disclosure will be described in detail below with reference to FIGS. 2-11.

FIG. 2 illustrates a flowchart of a method 200 that supports data handling based on PDU set in accordance with aspects of the present disclosure. The operations of the method 200 may be implemented by a device or its components as described herein. For example, the operations of the method 200 may be performed by a user equipment 104 as described in FIG. 1A. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 205, the user equipment receives, from a network device, a configuration associated with a PDU set for a DRB. In other words, the user equipment receives a configuration to configure the PDU set based handling for the DRB. For example, the user equipment may receive a RRC reconfiguration to configure a DRB from without PDU set handling to with PDU set handling. The PDU set based handling may be associated with parameters of legacy discard timer configuration, PDU-set importance-based discard timers configuration, PDU-set discard indicator, or PDU-set delay report configuration.

At 210, the user equipment receives a PDU in a PDU set from an upper layer of the user equipment. The PDU in the PDU set may be identified with information of the PDU set or not be identified with information of the PDU set. For example, upon receiving PDU set QoS parameters or PDU set handling indicator or PDU set indicator associated with a specific QoS flow from session management function (SMF) , the NAS layer of UE informs the APP layer of UE to provide PDU set information for the packets of the associated QoS flow to AS layer of UE. If updated QoS parameter associated with the specific QoS flow is provided by SMF without PDU set QoS parameters or PDU set handling indicator or PDU set indicator anymore, the NAS layer of UE informs the APP layer of UE to stop providing PDU set information for the packets of the associated QoS flow to the AS layer of UE.

FIG. 3 illustrates an example of PDU set identifying trigger procedure 300 in accordance with aspects of the present disclosure. The procedure 300 is described as bellow:

At 311, NAS layer of UE 302 receives the legacy discard timer configuration of a DRB from network, i.e., CN 303 e.g. by RRC reconfiguration message. At 313, the APP layer of UE 301 receives a PDCP SDU from upper layers (NAS layer of UE 302) . At 315, APP layer of UE 301 provides packets without PDU set information to AS layer of UE 303. At a reception of a PDCP SDU from upper layers, the transmitting PDCP entity of the DRB shall start the discardTimer associated with this PDCP SDU (if configured) . When the discardTimer expires for a PDCP SDU, the transmitting PDCP entity shall discard the PDCP SDU along with the corresponding PDCP Data PDU. At 317, NAS layer of UE 302 receives the PDCP discard timer configuration of the DRB from CN 303 e.g. by RRC reconfiguration message. At 319, the APP layer of UE 301 receives a PDCP SDU from NAS layer of UE 302. At 315, APP layer of UE 301 provides packets PDU set information to AS layer of UE 303.

In some embodiment, the configuration associated with a protocol data unit (PDU) set for a DRB includes at least one of: a PDU set discard indicator, a first discard timer, one or more second discard timer (s) , a PDU set delay report. If a PDU set discard indicator is configured, UE may discard the whole PDU set if one discard timer associated with a PDU in the PDU set expires. If a PDU set delay report is configured, UE may report the remaining discard time of a DRB to NW. One second discard timer may be corresponding to one or more PSI.

In an example, the PDCP configuration may include PDU set discard indication. In another example, the PDCP configuration may include at least one or more PSI discard timers, e.g., each timer is corresponding to at least one PSI level. In yet another example, the PDCP discard timer configuration may include at least one discard timer without corresponding to a PSI level (e.g., legacy discard timer) and one or more PSI discard timer. FIG. 4 illustrates an example of PDCP discard timer configuration of a DRB in accordance with aspects of the present disclosure. As shown in FIG. 4, there are: legacy discard timer, PSI-1 discard timer for data with lower than or equal to a PSI value, PSI-2 discard timer for data with higher than a PSI value. The PSI-1 discard timer may have two separate discard timers: PSI-1 discard timer-1 used in UL congestion mode and PSI-1 discard timer-2 used in UL no congestion mode. The PSI-2 discard timer may have two separate discard timers: PSI-2 discard timer-1 used in UL congestion mode and PSI-2 discard timer-2 used in UL non-congestion mode. For PSI-1 discard timer, legacy discard timer may be considered as the default PSI discard timer used in UL congestion mode if no PSI-1 discard timer-1 in UL congestion mode not introduced. For a PSI-2 discard timer, the legacy discard timer may be considered as the default PSI discard timer used in UL congestion mode if no PSI-2 discard timer-1 in UL congestion mode not introduced.

Reference is made back to FIG. 2, At 215, the user equipment starts a discard timer associated with a PDCP SDU corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment. In other words, the discard timer for the PDU is determined based on whether the information of the PDU set is identified, further which PSI is identified.

For example, packet 1 and 2 in FIG. 5 is not identified by the user equipment, the user equipment continues the running the PDCP discard timers (e.g., legacy discard timer) for the PDCP SDUs when receiving the RRC reconfiguration message in 315 as shown in FIG. 3. The PDCP discard timers is the stored configuration received before receiving the RRC reconfiguration. In addition, packet 3 and 4 in FIG. 5 is identified by the user equipment, the user equipment starts the discard timer associated with PDCP SDU available for transmission after receiving the RRC reconfiguration message.

In some embodiments, PDU set: one or more PDUs carrying the payload of one unit of information generated at the application level (e.g. frame (s) or video slice (s) etc. for XR Services) , as defined in TS 23.501 [3] . PDU set information includes at least one of (e.g., 1) , 5) , 1) +5, 1) +3) +5) ; or 1) +2) +3) +5) ) :

1) PDU Set Sequence Number;

2) Indication of End PDU of the PDU Set;

3) PDU Sequence Number within a PDU Set;

4) PDU Set Size in bytes;

5) PDU Set Importance (PSI) , which identifies the relative importance of a PDU Set compared to other PDU Sets within the same QoS Flow.

In some embodiments, the discard timer may comprise a first discard timer or a second discard timer. The first discard timer is not corresponding to a PDU set importance (PSI) level, and the second discard timer is corresponding to a PSI level. The first discard timer may be a legacy discard timer. The second discard timer may be a PSI discard timer (e.g., the discard timer is corresponding to at least a PSI) . The first discard timer may be the stored configuration received before receiving the RRC reconfiguration.

In some embodiments, in order to start the discard timer associated with the PDCP SDU, if the information of the PDU set for the PDU is not identified by the user equipment, the user equipment may start a first discard timer or a second discard timer corresponding to a default PSI level. For instance, if the PDU set information of the PDCP SDU (s) is not identified by UE, UE may start a default discard timer associated with a PDCP SDU. The default timer may be a legacy discard timer or a specific PSI-based discard timer, which is corresponding to a specific PSI, e.g., PSI-1 discard timer. The default timer may be a first discard timer or a default PSI-discard timer, which is corresponding to a default PSI, e.g., PSI-1.

In some embodiments, in order to start the discard timer associated with the PDCP SDU, if the information of the PDU set for the PDU is not identified by the user equipment, the user equipment may consider the PDU as a PDU set.

In some embodiments, in order to start the discard timer associated with the PDCP SDU, if the information of the PDU set for the PDU is not identified by the user equipment, the user equipment may consider the PSI of the PDU as a default or specific PSI, e.g., PSI-1.

In some embodiments, in order to start the discard timer associated with the PDCP SDU, if the PDU set for the PDU is not a complete PDU set, the user equipment may start a first discard timer which is not corresponding to a PSI level or a second discard timer corresponding to a default or specific PSI level. The PDU set for the PDU is not a complete PDU set refers to the PDU set information of not all PDUs in the PDU set are identified.

Alternatively, the second discard timer may be one of multiple discard timers, and the multiple discard timers are corresponding to one PSI. For example, a specific discard timer with larger or smaller value according to NW indication, which indicate UE use which one between the two discard timers (e.g., PSI-1-1 discard timer with larger value and PSI-1-2 discard timers with smaller value) corresponding to one PSI (e.g., PSI-1) . For example, UE starts the PSI-1-1discard timer if NW indicates UE in UL no-congestion mode, UE starts the PSI-1-2 discard timer if NW indicates UE in UL congestion mode.

Additionally, the first discard timer may be associated with a previous PDCP SDU of the PDCP SDU. In an example, UE starts a discard timer associated with a PDCP SDU, and the discard timer is same as that discard timer associated with the previous one PDCP SDU. For example, the discard timer for packet 3 is same as the discard timer for packet 2 in FIG. 5.

Alternatively or additionally, in order to start the discard timer associated with the PDCP SDU, if the information of the PDU set for the PDU is identified by the user equipment and the PDU set of the PDU is not complete, the user equipment may start a first discard timer without corresponding to a PSI level or a second discard timer corresponding to a default or specific PSI level. For example, in the case that the PDU set information of the PDCP SDU is identified by UE and not all the PDUs in a PDU set is identified, the user equipment may start the first discard timer or the specific PSI-based discard timer corresponding to a default PSI level. For example, in the case that the PDU set of the PDCP SDU is not a complete PDU set, the user equipment may start the first discard timer or the specific PSI-based discard timer. If the UE starts the specific PSI-based discard timer, UE may ignore the legacy discard timer immediately if receiving the RRC message.

In some embodiments, for a complete PDU set, the PDU set information of which are identified at the beginning of the start data of the PDU set.

Alternatively, UE ignores the first discard timer until the PDU set information of a PDCP SDU is identified or the PDU set of the PDCP SDU is a complete PDU set. Additionally, UE starts the PSI discard timer associated with a PDCP SDU after the PDU set information of the first PDCP SDU is identified.

In addition, the information of the PDU set is not identified for all the PDUs in the PDU set of the PDCP SDU by the UE may comprise: the information of the PDU set for the starting data in the PDU set is not identified or the PDU set for the PDCP SDU is not a complete PDU set.

In some embodiments, the user equipment may further ignore the first discard timer if the PDCP SDU is a PDCP SDU of a second PDU set. For example, UE ignores the first discard timer till reception of a PDCP SDU of the second PDU set. The second PDU set is a complete PDU set.

In some embodiments, the user equipment may start a second discard timer corresponding to a PSI level of the second PDU set associated with the PDCP SDU if the PDCP SDU is a PDCP SDU of the second PDU set. For example, UE starts the PSI discard timer associated with a PDCP SDU from the time at reception of a PDCP SDU of the second PDU set, and the PSI discard timer is corresponding to the PSI of the PDCP SDU. The second PDU set is a complete PDU set.

In some embodiments, the information of the PDU set for the first PDU in the second PDU set may be identified by the user equipment. For example, the first PDCP SDU is the starting data in a PDU set, and the PDU set information of the first PDCP SDU is identified. In some embodiments, the PDCP SDU may be a starting data of the second PDU set. In some embodiments, the discard timer may be the first discard timer, the PDU set is a first PDU set, and the second PDU set follows the first PDU set. In some embodiments, the second PDU set is a complete PDU set. In some embodiments, the first PDU set is not a complete PDU set. In other words, the UE identifies PDUs with PDU set information it shall start PDU set discard timer from a complete PDU Set. For example, UE starts the PSI discard timer associated with a PDCP SDU from the time at reception of a first PDCP SDU of a PDU set, the PSI discard timer is corresponding to the PSI of the PDCP SDU. In an example, UE ignores the first discard timer till reception of a first PDCP SDU of a PDU set. In another example, UE starts the PSI discard timer associated with a PDCP SDU from the time at reception of a first PDCP SDU of a PDU set, the PSI discard timer is corresponding to the PSI of the PDCP SDU.

In some embodiments, the configuration associated with a PDU set for a DRB is a first configuration, in order to start the discard timer associated with the PDCP SDU, the user equipment may receive a second configuration from the network device, and the second configuration indicates which discard timer is to be started for a PDCP SDU if PDU set information of the PDCP SDU is not identified or the PDU set of the PDCP SDU is not a complete PDU set. In the event that the information of the PDU set for the PDCP SDU is not identified by the user equipment or the PDU set of the PDCP PDU is not a complete PDU set, the user equipment may start a discard timer indicated according to the second configuration. In an example, UE starts a discard timer according to the network indication. The network indicates UE to starts a specific PSI discard timer or first discard timer associated with a PDCP SDU, the PDU set information of which is not identified by UE. Alternatively, the network indicates UE to starts a specific PSI discard timer or first discard timer associated with a PDCP SDU, which is not the first PDCP SDU in a PDU set or the PDU set of which is not a complete PDU set.

In some embodiments, in order to start the discard timer associated with the PDCP SDU, the user equipment may start a second discard timer associated with the PDCP SDU if the information of the PDU set for the PDU is identified. A PSI level of the second discard timer is the PSI level of the PDU set for the PDU. In an example, if the PDU set information of the PDCP SDU (s) can be identified by UE, UE may starts a PSI discard timer corresponding to the PSI of the PDCP SDU (e.g., packet 4 in FIG. 5) immediately if receiving RRC message.

In some embodiments, the user equipment may determine whether the PDCP SDU is starting data of the first PDU set. If the PDCP SDU is the starting data of the first PDU set, the user equipment may start a second discard timer corresponding to which a PSI level is the PSI of the first PDU set for the PDU. If the PDCP SDU is not the starting data of the first PDU set, the user equipment may not start a second discard timer until a first PDU of the second PDU set is identified. In the case where the UE identifies PDUs with PDU set information it shall starts a PSI discard timer corresponding to the PSI of the PDCP SDU (e.g., packet 5 in FIG. 5) from a complete PDU set.

In some embodiments, the user equipment may determine whether the PDU set of the PDCP SDU is a complete PDU set. If the PDU set of the PDCP SDU is a complete PDU set, the user equipment may start a second discard timer corresponding to which a PSI level is the PSI of the first PDU set for the PDU. If the PDU set of the PDCP SDU is not a complete PDU set, the user equipment may not start a second discard timer until the PDU set of the PDCP SDU is a complete PDU set. In the case where the UE identifies PDUs with PDU set information it shall starts a PSI discard timer corresponding to the PSI of the PDCP SDU (e.g., packet 5 in FIG. 5) from a complete PDU set.

In some scenarios, if the discard timer expires, and if the information of the PDU set for the PDU is identified, the user equipment may further determine whether the PDCP SDU is starting data of the PDU set or the PDU set of the PDCP SDU is a complete PDU set. If the PDCP SDU is the starting data of the PDU set or the PDU set of the PDCP SDU is a complete PDU set, the user equipment may discard all PDCP SDUs in the PDU set, and the PDCP SDU corresponding to a PDU in the PDU set. In other words, the UE may discard PDUs with PDU set information identified in a PDU set from a complete PDU set. For example, if the PDU set information of the SDUs in the PDU set of the PDCP SDU is identified, UE may discard the all PDCP SDUs belonging to a PDU set along with the corresponding PDCP PDUs if the PDU set discard indication is received in RRC message.

In some embodiments, if the discard timer expires, and if the information of the PDU set for the PDU is identified, and not all the information of the PDU set for the PDUs in the PDU set is identified or the PDU set of the PDCP SDU is not a complete PDU set, the user equipment may further discard the PDCP SDU along with a PDU corresponding to the PDCP SDU. In an example, the PDU set information of part of the SDUs of a PDU set is not identified, and UE does not identity a complete PDU set, e.g., the packet 3 in FIG. 7 is identified as not the first data of a PDU set. When the discard timer associated with a PDCP SDU expires, UE (i.e., the transmitting PDCP entity) may discard the PDCP SDU along with the corresponding PDCP Data PDU. The PDU set discard indication may be received in RRC message, and the discard timer may be a first discard timer or a PSI discard timer of a PDCP SDU.

In another example, the PDU set information of the SDU is not identified, and UE considers a PDU as a PDU set if PDU sets of which is not identified. Then UE performs the PDU set discard and the PDU set only including the PDU if the PDU set discard indication is configured regardless of using the PSI-based discard timer or the first discard timer.

UE considers a PDU as a PDU set if PDU sets of which is identified and not whole PDU set of the PDU is identified by the UE. Then UE performs the PDU set discard and the PDU set only including the PDU, regardless of using the PSI-based discard timer or the first discard timer. In an example, if packets 1, 2, 3, 4 are in a PDU set, and the PDU set information of packets 1, 2 is not identified, the PDU set information of packets 3, 4 is identified, then packets 3, 4 is separately discarded based on the discard timer expiration associated with each packet.

In some embodiments, if the discard timer expires, if the information of the PDU set for the PDU is identified, and not all the information of the PDU set for the PDUs in the PDU set is identified or the PDU set of the PDCP SDU is not a complete PDU set, the user equipment may further discard one or more PDCP SDUs in the PDU set of the PDU, for which the information of the PDU set is identified, along with one or more PDUs corresponding to the one or more PDCP SDUs. If the PDU set information of the SDUs is identified, the SDUs may be part of a PDU set or all data of a PDU set, and the discard timer is a first discard timer or a second discard timer of a PDCP SDU, UE discard the PDCP SDUs belonging to a PDU set along with the corresponding PDCP Data PDUs if the PDU set discard indication is received in RRC message.

In an example, if packets 1, 2, 3, 4 are in a PDU set, and the PDU set information of 1, 2, 3, 4 is identified, then packets 1, 2, 3, 4 are discarded together. In another example, if packets 1, 2, 3, 4 are in a PDU set, and the PDU set information of packets 1, 2 is not identified, the PDU set information of packets 3, 4 is identified, then packets 3, 4 are discarded together.

In some embodiments, if the discard timer expires, and the user equipment may further receive an indication to discard a PDU set from the network device. If the information of the PDU set for the PDU is identified, the user equipment may determine whether the PDCP SDU is starting data of the PDU set. If the PDCP SDU is the starting data of the PDU set, the user equipment may discard the PDCP SDUs in the PDU set, and the PDCP SDU corresponding to a PDU in the PDU set. If the PDCP SDU is not the starting data of the PDU set, the user equipment may discard the PDCP SDU along with one or more PDCP SDUs in the PDU set, and the information of the PDU set of the one or more PDCP SDUs is identified.

Alternatively, if the information of the PDU set for the PDU is not identified, the user equipment may further transmit a report of remaining discard time to the network device. The report comprising a shortest value of discard time of one or more PDCP SDUs in the PDU set. For instance, UE reports the remaining discard time of the buffered data to NW if delay report configured. In an example, if PDU sets is not identified, the remaining discard time of the discard timer may be the shortest value of a PDU set of the LCG. Additionally, for a logical channel group (LCG) including the logical channel (LCH) of the data, UE may report the remaining discard time per LCG or per LCH. Additionally, if PDU set information of a PDU is not identified, UE considers a PDU as a PDU set.

In some embodiments, if the information of the PDU set for the PDU is not identified, the user equipment may further transmit a report to the network device. The report indicates that the information of the PDU set is not identified. For example, UE may report NW that the PDU sets information is not identified. Additionally, the report “the PDU sets information is not identified” may be set as a cause value. The report may be generated and reported per DRB, per QoS flow or per LCH.

In some embodiments, the report is transmitted via a UE assistance information (UAI) message or a radio resource control (RRC) reconfiguration complete message.

In general, the user equipment starts a default discard timer, or a discard timer specified by NW associated with a packet without identifying the PDU set information. If the PDU set information of the PDCP SDU is not identified and the discard timer associated with the PDCP SDU expires, UE discards the PDCP SDU along with the corresponding PDCP Data PDU. If the PDU set information of the PDCP SDU is identified and the PDU set of the PDCP SDU is not a complete PDU set, and the discard timer associated with the PDCP SDU expires, UE discards the PDCP SDU along with the corresponding PDCP Data PDU. In addition, UE reports NW that the PDU sets information of a DRB or QoS flow is not identified to NW.

FIG. 6 illustrates a flowchart of a method 600 that supports data handling based on PDU set in accordance with aspects of the present disclosure. The operations of the method 600 may be implemented by a device or its components as described herein. For example, the operations of the method 600 may be performed by a user equipment 104 as described in FIG. 1A. In some implementations, the device may execute a set of instructions to control the function elements of the device to perform the described functions. Additionally, or alternatively, the device may perform aspects of the described functions using special-purpose hardware.

At 605, the user equipment determines to map a QoS flow from a first DRB to a second DRB. For example, UE is reconfigured a QoS flow mapped from first DRB to second DRB. FIG. 7 illustrates an example of QoS flow-DRB remapping procedure in accordance with aspects of the present disclosure. As shown in FIG. 7, if UE handovers from a source NG-RAN not supporting PDU set handling to a target NG-RAN supporting PDU set handling, there may be some packets 1, 2 without PDU set information buffered at PDCP layer or packets 3, 4 without PDU set information received after receiving the modification of QoS flow to DRB mapping. UE is configured with first DRB mapped to a QoS flow, the first DRB is configured without PDU set handling. UE is reconfigured with second DRB mapped to the QoS flow, which is originally mapped to first DRB without the PDU set handling, the second DRB is configured with PDU set handling. For example, the first DRB and the second DRB are mapped to the same QoS flow.

Reference is made back to FIG. 6, at 610, the user equipment routes a PDU of the QoS flow to the second DRB if PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment. As shown in FIG. 7, packet 5, packet 6 of the QoS flow identified PDU set information are routed to the second DRB. UE may start routing data of the QoS flow to second DRB from the starting data of the QoS flow, and PDU set information of the starting data is identified. In an example, the data (packet 5,6 in FIG. 7) of the QoS flow are not routed to the second DRB until the PDU set information of at least starting data of the QoS flow is identified. In another example, if PDU set information of starting data of the QoS flow is identified, UE will route the starting data and the subsequent data to the second DRB. In another example, the data (packet 3, 4 in FIG. 7) of the QoS flow with identified PDU set information and the data (packet 1, 2 in FIG. 7) of the QoS flow without identified PDU set information are routed to the first DRB.

In some embodiments, the user equipment may further route a PDU of the QoS flow to the first DRB if the PDU set information for the PDU identified by the user equipment. In some embodiments, the PDU set of the PDU is not a complete. For example, the data (packet 1, 2, 3, 4 in FIG. 7) of the QoS flow without identified PDU set information are routed to the first DRB. In another example, the data (packet 3, 4 in FIG. 7) of the QoS flow with identified PDU set information and the data (packet 1, 2 in FIG. 7) of the QoS flow without identified PDU set information are routed to the first DRB.

In some embodiments, the user equipment may further route a PDU of the QoS flow to the first DRB if the PDU set information for the PDU not identified by the user equipment. In some embodiments, the user equipment may further route a PDU of the QoS flow to the first DRB if the PDU set of the PDU is not a complete PDU set by the user equipment. In some embodiments, the user equipment may further route a PDU of the QoS flow to the first DRB if the PDU set information for a first PDU of the PDU set of the PDU is not identified by the user equipment. For example, the data (packet 1,2, 3, 4 in FIG. 7) of the QoS flow without identified PDU set information are routed to the first DRB. That is to say, the user equipment routes a PDU of the QoS flow to the first DRB until the PDU set of the PDU is a complete PDU set.

In some embodiments, the user equipment may further route a PDU of the QoS flow to the first DRB until a first PDU of a PDU set is identified by the user equipment or receiving a PDU in a complete PDU set. In an example, UE continues routing the data of the QoS flow to first DRB, the PDU set information of the data is not identified till the PDU set information of the first data of the QoS flow is identified. For example, after PDU set information of starting data of the QoS flow is identified, UE will not route data including the starting data and data which arriving later than the first data to the first DRB anymore. Even if PDU set information of later data of the QoS flow first is not identified, UE will not route the later data to the first DRB.

In some embodiments, the user equipment may further generate an end mark control PDU if the PDU set information for a first PDU of the PDU set is identified by the user equipment. In some embodiments, the user equipment may further generate an end mark control PDU if the PDU set of a PDU is not a complete PDU set. In some embodiments, the user equipment may further generate an end mark control PDU if the PDU set information for a PDU of the QoS flow is identified by the user equipment. In an example, UE may construct the end mark on first DRB to NW after the PDU set information of at least a data of the QoS flow first is identified. It may be defined as below:

In another example, UE may construct the end mark on first DRB after the PDU set information of a start data of a PDU set of the QoS flow first is identified from a complete PDU set. In yet another example, UE may construct the end mark on first DRB upon receiving the RRC reconfiguration. In another example, UE may construct the end mark on first DRB if receiving a PDU in a complete PDU set.

In some embodiments, the user equipment may further transmit the end mark on first DRB after completing transmission of data on the first DRB. For example, UE may transmit the end mark on first DRB to NW after the identification of PDU sets, PSI, data bursts of at least a data of the QoS flow first is identified.

In some embodiments, the first DRB may be not configured with PDU set handling, and the second DRB may be configured with PDU set handling. In some embodiments, the first PDU may be the starting data in the PDU set or the PDU set of the first PDU may be a complete PDU set.

In some embodiments, in order to determine to map the QoS flow from the first DRB to the second DRB, the user equipment may further receive a reconfiguration message from a network device. The reconfiguration message is used for mapping the QoS flow from the first DRB to the second DRB. Based on the reconfiguration message, the user equipment may determine to map the QoS flow from the first DRB to the second DRB. For example, the QoS flow to DRB remapping function may be enabled via a special indication by NW, or implicit configured by a QoS flow mapped from a DRB without PDU set handling to a DRB with PDU set handling.

In general, the user equipment routes the packets of the QoS flow to the first DRB for transmission without the PDU set information identified by the user equipment. The user equipment routes packets with the PDU set information identified of the QoS flow to the second DRB from a start packet with the PDU set information identified by the user equipment. In addition, the user equipment constructs an end mark control PDU if a first packet with the PDU set information is identified by UE and transmits the end mark on first DRB after completing transmission of data on first DRB.

FIG. 8 illustrates an example of a device 800 that supports data handling based on PDU set configuration in accordance with aspects of the present disclosure. The device 800 may be an example of a SMF 100 as described herein. The device 800 may support wireless communication with one or more network entities 102, UEs 104, or any combination thereof. The device 800 may include components for bi-directional communications including components for transmitting and receiving communications, such as a processor 802, a memory 804, a transceiver 806, and, optionally, an I/O controller 808. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 802, the memory 804, the transceiver 806, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. For example, the processor 802, the memory 804, the transceiver 806, or various combinations or components thereof may support a method for performing one or more of the operations described herein.

In some implementations, the processor 802, the memory 804, the transceiver 806, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some implementations, the processor 802 and the memory 804 coupled with the processor 802 may be configured to perform one or more of the functions described herein (e.g., executing, by the processor 802, instructions stored in the memory 804) .

For example, the processor 802 may support wireless communication at the device 800 in accordance with examples as disclosed herein. The processor 802 may be configured to operable to support a means for receiving, via the transceiver from a network device, a configuration associated with a protocol data unit (PDU) set for a data radio bearer (DRB) ; receiving a PDU in a PDU set from an upper layer of the user equipment; and starting a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment. The processor 802 may be further configured to operable to support a means for other actions described in FIG 2. The processor 802 may be configured to operable to support a means for determining to map a quality of service (QoS) flow from a first data radio bearer (DRB) to a second DRB; and routing a protocol data unit (PDU) of the QoS flow to the second DRB based on determining that PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment. The processor 802 may be further configured to operable to support a means for other actions described in FIG 6.

The processor 802 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some implementations, the processor 802 may be configured to operate a memory array using a memory controller. In some other implementations, a memory controller may be integrated into the processor 802. The processor 802 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 804) to cause the device 800 to perform various functions of the present disclosure.

The memory 804 may include random access memory (RAM) and read-only memory (ROM) . The memory 804 may store computer-readable, computer-executable code including instructions that, when executed by the processor 802 cause the device 800 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some implementations, the code may not be directly executable by the processor 802 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some implementations, the memory 804 may include, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The I/O controller 808 may manage input and output signals for the device 800. The I/O controller 808 may also manage peripherals not integrated into the device M02. In some implementations, the I/O controller 808 may represent a physical connection or port to an external peripheral. In some implementations, the I/O controller 808 may utilize an operating system such as or another known operating system. In some implementations, the I/O controller 808 may be implemented as part of a processor, such as the processor 806. In some implementations, a user may interact with the device 800 via the I/O controller 808 or via hardware components controlled by the I/O controller 808.

In some implementations, the device 800 may include a single antenna 810. However, in some other implementations, the device 800 may have more than one antenna 810 (i.e., multiple antennas) , including multiple antenna panels or antenna arrays, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 806 may communicate bi-directionally, via the one or more antennas 810, wired, or wireless links as described herein. For example, the transceiver 806 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 806 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 810 for transmission, and to demodulate packets received from the one or more antennas 810. The transceiver 806 may include one or more transmit chains, one or more receive chains, or a combination thereof.

A transmit chain may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmit chain may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmit chain may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmit chain may also include one or more antennas 810 for transmitting the amplified signal into the air or wireless medium.

A receive chain may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receive chain may include one or more antennas 810 for receive the signal over the air or wireless medium. The receive chain may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receive chain may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receive chain may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

FIG. 9 illustrates an example of a processor 900 that supports data handling based on PDU set configuration in accordance with aspects of the present disclosure. The processor 900 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 900 may include a controller 902 configured to perform various operations in accordance with examples as described herein. The processor 900 may optionally include at least one memory 904, such as L1/L2/L3 cache. Additionally, or alternatively, the processor 900 may optionally include one or more arithmetic-logic units (ALUs) 900. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 900 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 900) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 902 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 900 to cause the processor 900 to support various operations in accordance with examples as described herein. For example, the controller 902 may operate as a control unit of the processor 900, generating control signals that manage the operation of various components of the processor 900. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 902 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 904 and determine subsequent instruction (s) to be executed to cause the processor 900 to support various operations in accordance with examples as described herein. The controller 902 may be configured to track memory address of instructions associated with the memory 904. The controller 902 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 902 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 900 to cause the processor 900 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 902 may be configured to manage flow of data within the processor 900. The controller 902 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 900.

The memory 904 may include one or more caches (e.g., memory local to or included in the processor 900 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementation, the memory 904 may reside within or on a processor chipset (e.g., local to the processor 900) . In some other implementations, the memory 904 may reside external to the processor chipset (e.g., remote to the processor 900) .

The memory 904 may store computer-readable, computer-executable code including instructions that, when executed by the processor 900, cause the processor 900 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 902 and/or the processor 900 may be configured to execute computer-readable instructions stored in the memory 904 to cause the processor 900 to perform various functions. For example, the processor 900 and/or the controller 902 may be coupled with or to the memory 904, and the processor 900, the controller 902, and the memory 904 may be configured to perform various functions described herein. In some examples, the processor 900 may include multiple processors and the memory 904 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 900 may be configured to support various operations in accordance with examples as described herein. In some implementation, the one or more ALUs 900 may reside within or on a processor chipset (e.g., the processor 900) . In some other implementations, the one or more ALUs 900 may reside external to the processor chipset (e.g., the processor 900) . One or more ALUs 900 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 900 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 900 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 900 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 900 to handle conditional operations, comparisons, and bitwise operations.

The processor 900 may support wireless communication in accordance with examples as disclosed herein. The processor 900 may be configured to or operable to support a means for receiving, via the transceiver from a network device, a configuration associated with a protocol data unit (PDU) set for a data radio bearer (DRB) ; receiving a PDU in a PDU set from an upper layer of the user equipment; and starting a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment. The processor 902 may be further configured to operable to support a means for other actions described in FIG 2.

The processor 900 may be configured to or operable to support a means for d determining to map a quality of service (QoS) flow from a first data radio bearer (DRB) to a second DRB; and routing a protocol data unit (PDU) of the QoS flow to the second DRB based on determining that PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment. The processor 902 may be further configured to operable to support a means for other actions described in FIG 6.

It should be noted that the methods described herein describes possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

As used herein, including in the claims, an article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A user equipment (UE) comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

receive, via the transceiver from a network device, a configuration associated with a protocol data unit (PDU) set for a data radio bearer (DRB) ;

receive a PDU in a PDU set from an upper layer of the user equipment; and

start a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment.
The user equipment of claim 1, wherein the information of the PDU set comprises at least one of the following:

a sequence number of the PDU set;

an indication of end PDU of the PDU set;

a sequence number of a PDU within the PDU set;

a size of the PDU set in bytes; or

PDU set importance (PSI) level of the PDU set.
The user equipment of claim 1, wherein the discard timer comprises one of the following:

a first discard timer, which is not corresponding to a PSI level; or

a second discard timer corresponding to a PSI level.
The user equipment of claim 1, wherein starting the discard timer associated with the PDCP SDU comprises:

based on determining that the information of the PDU set for the PDU is not identified by the user equipment, starting one of the following:

a first discard timer, which is not corresponding to a PSI level; or

a second discard timer corresponding to a default PSI level.
The user equipment of claim 1, wherein starting the discard timer associated with the PDCP SDU comprises:

based on determining that the PDU set for the PDU is not a complete PDU set, starting one of the following:

a first discard timer, which is not corresponding to a PSI level; or

a second discard timer corresponding to a default PSI level.
The user equipment of claim 1, wherein the processor is further caused to:

based on determining that the information of the PDU set for the PDU is not identified by the user equipment, consider the PDU as a PDU set.
The user equipment of claim 1, wherein the processor is further caused to:

based on determining that the information of the PDU set for the PDU is not identified by the user equipment, consider the PSI of the PDU as a default PSI.
The user equipment of claim 1, wherein starting the discard timer associated with the PDCP SDU comprises:

based on determining that the information of the PDU set for the PDU is identified by the user equipment and the PDU set is not complete for all the PDUs in the PDU set of the PDCP SDU by the UE, starting one of the following:

a first discard timer, which is not corresponding to a PDU set importance (PSI) level; or

a second discard timer corresponding to a default PSI level.
The user equipment of claim 8, wherein the information of the PDU set is not identified for all the PDUs in the PDU set of the PDCP SDU by the UE comprise: the information of the PDU set for the starting data in the PDU set is not identified or the PDU set for the PDCP SDU is not a complete PDU set.
The user equipment of claim 3, the processor is further configured to:

ignore the first discard timer if the PDCP SDU is a PDCP SDU of a second PDU set; or

start a second discard timer corresponding to a PSI level of the second PDU set if the PDCP SDU is a PDCP SDU of the second PDU set.
The user equipment of claim 10, wherein:

the information of the PDU set for the first PDU in the second PDU set is identified by the user equipment, the PDCP SDU is a starting data of the second PDU set;

the discard timer is the first discard timer, the PDU set is a first PDU set, and the second PDU set follows the first PDU set;

the second PDU set is a complete PDU set; or

the first PDU set is not a complete PDU set.
The user equipment of claim 1, wherein starting the discard timer associated with the PDCP SDU comprises:

starting a second discard timer associated with the PDCP SDU based on determining that the information of the PDU set for the PDU is identified, wherein a PSI level of the second discard timer is the PSI level of the PDU set for the PDU.
The user equipment of claim 12, wherein the processor is further configured to:

determining whether the PDCP SDU is starting data of the first PDU set or the PDU set of the PDCP PDU is not a complete PDU set;

based on determining that the PDCP SDU is the starting data of the first PDU set or the PDU set of the PDCP PDU is a complete PDU set, starting a second discard timer corresponding to which a PSI level is the PSI of the first PDU set for the PDU; or

based on determining that the PDCP SDU is not the starting data of the first PDU set or the PDU set of the PDCP PDU is not a complete PDU set, not starting a second discard timer until a first PDU of the PDU set is identified.
The user equipment of claim 1, wherein if the discard timer expires, and the processor is further configured to:

based on determining that the information of the PDU set for the PDU is identified, and based on determining that not all the information of the PDU set for the PDUs in the PDU set is identified or the PDU set of the PDCP SDU is not a complete PDU set, discard one or more PDCP SDUs, for which the information of the PDU set is identified, along with one or more PDUs corresponding to the one or more PDCP SDUs.
The user equipment of claims 1-14, wherein the processor is further configured to:

based on determining that the information of the PDU set for the PDU is not identified, transmit, to the network device, a report indicating that the information of the PDU set is not identified.
A user equipment (UE) comprising:

a processor; and

a transceiver coupled to the processor,

wherein the processor is configured to:

determine to map a quality of service (QoS) flow from a first data radio bearer (DRB) to a second DRB; and

route a protocol data unit (PDU) of the QoS flow to the second DRB based on determining that PDU set information for a first PDU of the PDU set for the PDU is identified by the user equipment.
The user equipment of claim 16, wherein the processor is further configured to:

route a PDU of the QoS flow to the first DRB based on determining that the PDU set information for the PDU not identified by the user equipment; or

route a PDU of the QoS flow to the first DRB based on determining that the PDU set of the PDU is not a complete PDU set by the user equipment; or

route a PDU of the QoS flow to the first DRB based on determining that the PDU set information for a first PDU of the PDU set of the PDU is not identified by the user equipment.
The user equipment of claim 16, wherein the processor is further configured to:

route a PDU of the QoS flow to the first DRB until a first PDU of a PDU set is identified by the user equipment or the PDU set of the PDU is a complete PDU set.
A method performed by a user equipment, comprising:

receiving, via the transceiver from a network device, a configuration associated with a protocol data unit (PDU) set for a data radio bearer (DRB) ;

receiving a PDU in a PDU set from an upper layer of the user equipment; and

starting a discard timer associated with a packet data convergence protocol (PDCP) service data unit (SDU) corresponding to the PDU based on whether information of the PDU set for the PDU is identified by the user equipment.
A method performed by a user equipment, comprising:

determining to map a quality of service (QoS) flow from a first data radio bearer (DRB) to a second DRB; and

routing a protocol data unit (PDU) of the QoS flow to the second DRB based on determining that PDU set information for a first PDU of the PDU set is identified by the user equipment.