Terminal device, base station device, and method

Abstract

A terminal device includes a reception unit that receives an RRC reconfiguration message including a radio bearer configuration information element, and a processing unit that establishes an SDAP entity in a case where a radio bearer identifier included in the radio bearer configuration information element is not present in a configuration of the terminal device, the radio bearer configuration information element includes an SDAP configuration information element, and an SDAP entity corresponding to a PDU session information element included in the SDAP configuration information element is not present, and notifies an upper layer that a user plane resource for the PDU session has been established in a case where the SDAP entity corresponding to the PDU session information element is not present before the RRC reconfiguration message is received.

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201980070919.9, filed on October 29, 2019, entitled "Terminal device, base station device and method". Technical Field

[0002] This invention relates to terminal devices, base station devices, and methods.

[0003] This application claims priority to Japanese Patent Application No. 2018-205078, filed in Japan on October 31, 2018, the contents of which are incorporated herein by reference. Background Technology

[0004] The 3rd Generation Partnership Project (3GPP) studied radio access methods, radio networks (hereinafter referred to as "Long Term Evolution (LTE: registered trademark)" or "Evolved Universal Terrestrial Radio Access (EUTRA)"), and core networks (hereinafter referred to as "Evolved Packet Core (EPC)").

[0005] Furthermore, within 3GPP, technical research and standardization were conducted on LTE-Advanced Pro, an extension of LTE, and NR (New Radiotechnology), a new radio access technology, as radio access methods and wireless network technologies for fifth-generation cellular systems (Non-Patent Document 1). Additionally, research was also conducted on 5GC (5Generation Core Network), the core network for fifth-generation cellular systems (Non-Patent Document 2).

[0006] Existing technical documents

[0007] Non-patent literature

[0008] Non-patent document 1: 3GPP RP-170855, "Work Item on New Radio (NR) Access Technology"

[0009] Non-patent document 2: 3GPP TS23.501v.15.3.0, “System Architecture for the 5G System; Stage 2”

[0010] Non-patent document 3: 3GPP TS 36.300v.15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA) and Evolved Universal Terestrial Radio Access Network (E-UTRAN); Overall description; Stage 2"

[0011] Non-patent literature 4: 3GPP TS 36.331 v.15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specifications"

[0012] Non-patent literature 5: 3GPP TS 36.323 v.15.1.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Packet Data Convergence Protocol (PDCP) specification"

[0013] Non-patent document 6: 3GPP TS 36.322 v.15.1.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Radio Link Control (RLC) protocol specification"

[0014] Non-patent literature 7: 3GPP TS 36.321 v.15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification"

[0015] Non-patent literature 8: 3GPP TS 37.340 v.15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA) and NR; Multi-Connectivity; Stage 2"

[0016] Non-patent literature 9: 3GPP TS 38.300 v.15.3.1, “NR; NR and NG-RAN Overall description; Stage 2”

[0017] Non-patent literature 10: 3GPP TS 38.331 v.15.3.0, "NR; Radio Resource Control (RRC); Protocol specifications"

[0018] Non-patent literature 11: 3GPP TS 38.323 v.15.3.0, "NR; Packet Data Convergence Protocol (PDCP) specification"

[0019] Non-patent document 12: 3GPP TS 38.322 v.15.3.0, “NR; Radio Link Control (RLC) protocol specification”

[0020] Non-patent literature 13: 3GPP TS 38.321 v.15.3.0, “NR; Medium Access Control (MAC) protocol specification”

[0021] Non-patent document 14: 3GPP TS 23.401 v14.3.0, “General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access”

[0022] Non-patent document 15: 3GPP TS 23.502 v.15.3.0, “Procedure for 5G System; Stage 2”

[0023] Non-patent document 16: 3GPP TS 37.324 v.15.1.0, "NR; Service Data Adaptation Protocol (SDAP) specification"

[0024] Non-patent document 17: 3GPP RP-161266, “5G Architecture Options - Full Set” Summary of the Invention

[0025] The problem the invention aims to solve

[0026] As part of the NR technology research, the protocol of the radio access layer, which manages QoS (Quality of Service) between the upper layers above the IP (Internet Protocol) layer and the NR radio access layer, was studied.

[0027] However, if QoS management between the upper layer and the wireless access layer is not performed correctly, there is a problem that communication between the base station device and the terminal device cannot be carried out efficiently.

[0028] One aspect of the present invention is made in view of the above circumstances, and one of its objectives is to provide a terminal device, a base station device, a method for the terminal device, and a method for the base station device that can communicate efficiently with a base station device.

[0029] Technical solution

[0030] To achieve the above objectives, one solution of the present invention is as follows. A terminal device for communicating with a base station includes: a receiving unit that receives an RRC (Radio Resource Control) reset message including radio bearer setting information elements from the base station; and a processing unit that, when the terminal device's settings do not include a radio bearer identifier included in the radio bearer setting information elements, and the radio bearer setting information elements include SDAP (Service Data Adaptation Protocol) setting information elements, and an SDAP entity corresponding to a PDU (Protocol Data Unit) session information element included in the SDAP setting information elements does not exist, establishes an SDAP entity; and when the terminal device's settings do not include a radio bearer identifier included in the radio bearer setting information elements, and the radio bearer setting information elements include SDAP setting information elements, and an SDAP entity corresponding to a PDU session information element included in the SDAP setting information elements does not exist, and an SDAP entity corresponding to the PDU session information element did not exist before receiving the RRC reset message, notifies an upper layer that user-plane resources for a PDU session have been established.

[0031] Furthermore, one aspect of the present invention is a base station apparatus for communicating with a terminal device, comprising: a transmitting unit that transmits an RRC (Radio Resource Control) reset message including radio bearer configuration information elements to the terminal device; and a processing unit that, by including radio bearer configuration information elements in the RRC reset message, causes the terminal device to perform processing, the processing including: the radio bearer identifier included in the radio bearer configuration information elements is not present in the settings of the terminal device, the radio bearer configuration information elements include SDAP (Service Data Adaptation Protocol) configuration information elements, and the PDU (Protocol Data Unit) included in the SDAP configuration information elements is not present. If the SDAP entity corresponding to the PDU session information element does not exist, an SDAP entity is established; and if the radio bearer identifier included in the radio bearer configuration information element does not exist in the settings of the terminal device, and the radio bearer configuration information element includes an SDAP configuration information element, and the SDAP entity corresponding to the PDU session information element included in the SDAP configuration information element does not exist, and if the SDAP entity corresponding to the PDU session information element does not exist before the terminal device receives the RRC reset message, the upper layer is notified that user-plane resources for the PDU session have been established.

[0032] Furthermore, one aspect of the present invention is a communication method for a terminal device communicating with a base station device. The method involves receiving an RRC (Radio Resource Control) reset message from the base station device, including radio bearer configuration information elements. If the terminal device's configuration does not include a radio bearer identifier in the radio bearer configuration information elements, and the radio bearer configuration information elements include SDAP (Service Data Adaptation Protocol) configuration information elements, and the SDAP entity corresponding to the PDU (Protocol Data Unit) session information element included in the SDAP configuration information elements does not exist, an SDAP entity is established. If the terminal device's configuration does not include a radio bearer identifier in the radio bearer configuration information elements, and the radio bearer configuration information elements include SDAP configuration information elements, and the SDAP entity corresponding to the PDU session information element included in the SDAP configuration information elements does not exist, and the SDAP entity corresponding to the PDU session did not exist before receiving the RRC reset message, the method notifies the upper layer that user-plane resources for the PDU session information elements have been established.

[0033] Furthermore, one aspect of the present invention is a communication method for a base station device communicating with a terminal device. The method involves sending an RRC (Radio Resource Control) reset message including radio bearer configuration information elements to the terminal device. By including radio bearer configuration information elements in the RRC reset message, the terminal device performs processing, which includes the following steps: If the radio bearer identifier included in the radio bearer configuration information elements is absent in the terminal device's settings, and the radio bearer configuration information elements include SDAP (Service Data Adaptation Protocol) configuration information elements, and the SDAP entity corresponding to the PDU (Protocol Data Unit) session information element included in the SDAP configuration information elements does not exist, an SDAP entity is established; and if the radio bearer identifier included in the radio bearer configuration information elements is absent in the terminal device's settings, and the radio bearer configuration information elements include SDAP configuration information elements, and the SDAP entity corresponding to the PDU session information element included in the SDAP configuration information elements does not exist, and the SDAP entity corresponding to the PDU session information element does not exist before the terminal device receives the RRC reset message, the method notifies the upper layer that user-plane resources for the PDU session information element have been established. resources).

[0034] It should be noted that these specific solutions can be implemented by systems, devices, methods, integrated circuits, computer programs, or recording media, or by any combination of systems, devices, methods, integrated circuits, computer programs, and recording media.

[0035] Beneficial effects

[0036] According to one aspect of the present invention, the terminal device can reduce the complexity of protocol processing and perform communication efficiently. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the communication system according to various embodiments of the present invention.

[0038] Figure 2A This is a protocol stack diagram of the UP (User Plane) of the terminal device and the base station device in the E-UTRA of various embodiments of the present invention.

[0039] Figure 2B This is a protocol stack diagram of CP (Control Plane).

[0040] Figure 3A This is a protocol stack diagram of the terminal device and the UP of the base station device in the NR of various embodiments of the present invention.

[0041] Figure 3B This is a protocol stack diagram of the CP of the terminal device and the base station device in the NR of various embodiments of the present invention.

[0042] Figure 4 This is a diagram illustrating an example of the RRC reset process according to various embodiments of the present invention.

[0043] Figure 5 This is a block diagram illustrating the configuration of the terminal device according to various embodiments of the present invention.

[0044] Figure 6 This is a block diagram illustrating the configuration of a base station device according to various embodiments of the present invention.

[0045] Figure 7 This is a diagram illustrating an example of the information and ASN.1 (Abstract Syntax Notation One) description of the wireless bearer settings and information of various embodiments of the present invention.

[0046] Figure 8 This is a diagram illustrating an example of a processing method according to an embodiment of the present invention.

[0047] Figure 9 This is a diagram illustrating another example of a processing method according to an embodiment of the present invention. Detailed Implementation

[0048] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0049] LTE (and LTE-A Pro) and NR can be defined as different RATs. Furthermore, NR can be defined as a technology included in LTE. LTE can be defined as a technology included in NR. Furthermore, the LTE described in Non-Patent Document 7, which can connect to NR via Multi RAT Dual connectivity (MR-DC), can be distinguished from existing LTE. This embodiment can be applied to NR, LTE, and other RATs. In the following description, terms associated with LTE and NR are used, but they can also be applied to other technologies using other terms. Furthermore, the term E-UTRA in this embodiment can be replaced by the term LTE, and vice versa.

[0050] Figure 1 This is a schematic diagram of the communication system according to various embodiments of the present invention.

[0051] E-UTRA 100 is a radio access technology described in Non-Patent Document 3, etc., consisting of cell groups (CGs) composed of one or more frequency bands. eNB (E-UTRAN Node B) 102 is an E-UTRA base station device. EPC (Evolved Packet Core) 104 is a core network described in Non-Patent Document 14, etc., designed as an E-UTRA core network. Interface 112 is the interface between eNB 102 and EPC 104, containing a control plane (CP) through which control signals pass and a user plane (UP) through which user data passes.

[0052] NR106 is a radio access technology described in Non-Patent Document 9, etc., comprising a Cell Group (CG) consisting of one or more frequency bands. gNB (gNode B) 108 is an NR base station device. 5GC110 is a core network described in Non-Patent Document 2, etc., designed as an NR core network, but can also be used as an E-UTRA core network with the function of connecting to 5CG. The following E-UTRA may include E-UTRAs with the function of connecting to 5CG.

[0053] Interface 114 is the interface between eNB102 and 5GC110; interface 116 is the interface between gNB108 and 5GC110; interface 118 is the interface between gNB108 and EPC104; interface 120 is the interface between eNB102 and gNB108; and interface 124 is the interface between EPC104 and 5GC110. Interfaces 114, 116, 118, 120, and 124 can be used only through the CP, only through the UP, or through both the CP and UP. Furthermore, interfaces 114, 116, 118, 120, and 124 may not exist depending on the communication system provided by the telecommunications operator.

[0054] UE122 is a terminal device corresponding to NR, or corresponding to both E-UTRA and NR.

[0055] Figure 2A and Figure 2B This is a protocol stack diagram of the UP and CP of the terminal device and the base station device in the E-UTRA wireless access layer of various embodiments of the present invention.

[0056] Figure 2AThis is a diagram of the UP protocol stack used by UE122 and eNB102 when communicating in E-UTRA100.

[0057] PHY (Physical layer) 200 is the radio physical layer, which provides transmission services to the upper layer using a physical channel. PHY 200 connects to the upper-level MAC (Medium Access Control layer) 202 (described later) via a transport channel. Data moves between MAC 202 and PHY 200 via the transport channel. Data transmission and reception between the PHYs of UE122 and eNB102 are conducted via the radio physical channel.

[0058] MAC202 is a medium access control layer that maps multiple logical channels to multiple transmission channels. MAC202 connects to the higher-level RLC (Radio Link Control layer) 204 (described later) via these logical channels. Logical channels are broadly classified according to the type of information transmitted, into control channels for transmitting control information and service channels for transmitting user information. MAC202 has functions such as controlling PHY200 for intermittent transmit / receive (DRX / DTX), executing random access procedures, notifying transmit power, and performing HARQ control (Non-Patent Document 7).

[0059] RLC204 is a radio link control layer that segments and adjusts the data size received from the upper-level PDCP (Packet Data Convergence Protocol Layer) 206 (described later) to enable the lower layer to transmit data appropriately. Furthermore, RLC200 also has functions to guarantee the QoS (Quality of Service) requested by each data transmission. That is, RLC204 has functions such as data retransmission control (Non-Patent Document 6).

[0060] PDCP206 is a packet data convergence protocol layer for efficient transmission of IP packets as user data over wireless networks. PDCP206 can have header compression functionality to compress unnecessary control information. Furthermore, PDCP206 can also have data encryption functionality (Non-Patent Document 5).

[0061] It should be noted that the data processed in MAC202, RLC204, and PDCP206 are respectively referred to as MAC PDU (Protocol Data Unit), RLC PDU, and PDCP PDU. Furthermore, the data transferred from the upper layer to MAC202, RLC204, or PDCP206, or transferred to the upper layer, are respectively referred to as MAC SDU (Service Data Unit), RLC SDU, and PDCP SDU.

[0062] Figure 2B This is a protocol stack diagram of the CP used when UE122 communicates with eNB102 in E-UTRA100.

[0063] In the CP protocol stack, in addition to PHY200, MAC202, RLC204, and PDCP206, there is also RRC (Radio Resource Control layer) 208. RRC208 is a radio link control layer that performs settings / reconfigurations of radio bearers (RBs) and controls logical, transport, and physical channels. RBs can be divided into signaling radio bearers (SRBs) and data radio bearers (DRBs). SRBs can be used as paths for sending RRC messages as control information. DRBs can be used as paths for sending user data. The settings of each RB can be performed between the RRC208 of eNB102 and UE122 (Non-Patent Document 4).

[0064] The functional classification of MAC202, RLC204, PDCP206, and RRC208 described above is an example; it is not necessary to implement only some or all of these functions. Furthermore, some or all of the functions of each layer can be included in other layers.

[0065] It should be noted that the IP layer and the layers above it, such as TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and the application layer, are above the PDCP layer (not shown). Furthermore, the RRC layer and NAS (non-access stratum) layer are also above the SDAP layer (not shown). In other words, the PDCP layer is below the RRC layer, NAS layer, IP layer, and the layers above it, such as TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and the application layer.

[0066] Figure 3A and Figure 3B This is a protocol stack diagram of the UP and CP of the terminal device and the base station device in the NR wireless access layer of various embodiments of the present invention.

[0067] Figure 3A This is a diagram of the UP protocol stack used by UE122 and gNB108 to communicate in NR106.

[0068] PHY (Physical layer) 300 is the radio physical layer of NR, which can provide transmission services to the upper layer using a physical channel. PHY 300 can connect to the upper-level MAC (Medium Access Control layer) 302 (described later) via a transport channel. Data can move between MAC 302 and PHY 300 via the transport channel. Data can be sent and received between the PHY of UE122 and gNB108 via the radio physical channel.

[0069] MAC302 is a medium access control layer that maps multiple logical channels to multiple transmission channels. MAC302 can connect to the higher-level RLC (Radio Link Control layer) 304 (described later) via logical channels. Logical channels can be broadly classified according to the type of information transmitted, into control channels transmitting control information and service channels transmitting user information. MAC302 may have functions such as controlling PHY300 for intermittent transmit / receive (DRX / DTX), executing random access procedures, notifying transmit power information, and performing HARQ control (Non-Patent Document 13).

[0070] RLC304 is a radio link control layer that segments and adjusts the data size of data received from the upper-level PDCP (Packet Data Convergence Protocol Layer) 206 (described later) to enable appropriate data transmission by the lower layers. Furthermore, RLC304 may also have functions to guarantee the requested QoS (Quality of Service) for each data transmission. That is, RLC304 may have functions such as data retransmission control (Non-Patent Document 12).

[0071] PDCP306 is a packet data convergence protocol layer for efficient transmission of IP packets as user data over wireless networks. PDCP306 can have header compression functionality to compress unnecessary control information. Furthermore, PDCP306 can also have data encryption functionality (Non-Patent Document 11).

[0072] SDAP (Service Data Adaptation Protocol) 310 is a Service Data Adaptation Protocol layer with the following functions: establishing (mapping) the correspondence between downlink QoS flows and DRBs transmitted from the core network to the terminal device via the base station device, and mapping uplink QoS flows transmitted from the terminal device to the core network via the base station device, and storing mapping rule information (Non-Patent Document 16). When the terminal device receives SDAP SDUs along with QoS flow information from the upper layer, it assigns the SDAP SDUs to the corresponding DRBs based on the stored QoS flow and DRB mapping rules. In the absence of stored QoS flow and DRB mapping rules, the SDAP SDUs can be assigned to the default radio bearer (default DRB). A QoS flow consists of one or more Service Data Flows (SDFs) processed by the same QoS policy (Non-Patent Document 2). In addition, SDAP can also have the function of reflecting QoS, which maps uplink QoS flows to DRBs based on downlink QoS flow information. Furthermore, in the event of a change in the rules governing the correspondence between QoS flows and DRBs, an End Marker DPU can be created and sent to the DRB before the change to ensure in-sequence delivery of SDAP SDUs (Non-Patent Literature 2, Non-Patent Literature 16).

[0073] The end marker PDU is the SDAP control PDU described in Non-Patent Document 16, used by the SDAP entity of the UE to notify the end of the mapping between the QoS flow identifier included in the QoS flow identifier field of this end marker PDU and the radio bearer that sent this end marker PDU.

[0074] It should be noted that the IP layer and the layers above it, such as TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and the application layer, are above the SDAP layer (not shown). Additionally, the RRC layer and NAS (non-access stratum) layer are also above the SDAP layer (not shown). In the NAS layer, the mapping between service data streams and QoS streams is established. In other words, the SDAP layer is below the RRC layer, NAS layer, IP layer, and the layers above it, such as TCP (Transmission Control Protocol), UDP (User Datagram Protocol), and the application layer.

[0075] It should be noted that data processed in MAC302, RLC304, PDCP306, and SDAP310 can be referred to as MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU, and SDAP PDU, respectively. Furthermore, data transferred from the upper layer to MAC202, RLC204, PDCP206, or data transferred to the upper layer can be referred to as MAC SDU (Service Data Unit), RLC SDU, PDCP SDU, and SDAP SDU, respectively.

[0076] Figure 3B This is a protocol stack diagram of the CP used by UE122 to communicate with gNB 108 in NR106.

[0077] In the CP protocol stack, in addition to PHY300, MAC302, RLC304, and PDCP306, there is also RRC (Radio Resource Control layer) 308. RRC308 is the Radio Link Control layer that performs settings / reconfigurations of Radio Bearers (RBs) and controls logical, transport, and physical channels. RBs can be divided into Signaling Radio Bearers (SRBs) and Data Radio Bearers (DRBs). SRBs can be used as paths for sending RRC messages as control information. DRBs can be used as paths for sending user data. The settings of each RB can be performed between gNB108 and UE122's RRC308. Furthermore, the portion of an RB consisting of RLC304 and MAC302 can also be referred to as an RLC bearer (Non-Patent Document 10).

[0078] The functional classification of MAC302, RLC304, PDCP306, SDAP310, and RRC308 described above is an example; it is not necessary to implement only some or all of the functions. Furthermore, some or all of the functions of each layer can also be included in other layers.

[0079] It should be noted that, in the various embodiments of the present invention, to distinguish between the E-UTRA protocol and the NR protocol, MAC202, RLC204, PDCP206, and RRC208 will be referred to as E-UTRA MAC or LTE MAC, E-UTRA RLC or LTE RLC, E-UTRA PDCP or LTE PDCP, and E-UTRA RRC or LTE RRC, respectively. Furthermore, MAC302, RLC304, PDCP306, and RRC308 will be referred to as NR MAC, NR RLC, NR RLC, and NR RRC, respectively. Alternatively, spaces may be used to denote terms such as E-UTRA PDCP or LTE PDCP, NR PDCP, etc.

[0080] In addition, such as Figure 1 As shown, eNB102, gNB108, EPC104, and 5GC110 can be connected via interfaces 112, 116, 118, 120, and 114. Therefore, to accommodate various communication systems, Figure 2B RRC208 can be replaced with Figure 3B RRC308. In addition, Figure 2B PDCP206 can also be replaced with Figure 3B PDCP306. In addition... Figure 3B The RRC308 may include Figure 2B The functions of RRC208. In addition. Figure 3B PDCP306 can be Figure 2B PDCP206. Furthermore, even in E-UTRA100, when UE122 communicates with eNB102, NR PDCP can be used as PDCP.

[0081] (Implementation Method)

[0082] use Figures 1 to 9 The embodiments of the present invention will be described below. In an embodiment of the present invention, when an SDAP entity is established, the upper layer is notified that user plane resources for the PDU session have been established or configured when a new PDU session is established.

[0083] Figure 4This is a diagram illustrating an example of the flow of the RRC reset process according to various embodiments of the present invention. It should be noted that the RRC reset process can be an RRC connection reset process.

[0084] The RRC Connection Reconfiguration process, as described in Non-Patent Document 4, involves settings for handover and measurement, in addition to establishing, modifying, and releasing Radio Bearers (RBs) and secondary cells in LTE. Conversely, the RRC Reconfiguration process, as described in Non-Patent Document 10, involves settings for handover (accompanied by synchronization reconfiguration), and measurement, in addition to establishing, modifying, and releasing RBs and secondary cells in NR. It should be noted that in the embodiments of this invention, the information included in each message of the RRC Connection Reconfiguration process for setting up, modifying, releasing, and secondary cells, as well as handover and measurement, is referred to as setting information. It should also be noted that the setting information is not limited to the settings described above; it can be other settings, and is not limited to the RRC Connection Reconfiguration process, but can also be included in messages of other processes.

[0085] Furthermore, in the MR-DC (Multi-RAT Dual Connectivity) described in Non-Patent Document 8, the RRC connection reconfiguration process can be used, in particular, as EN-DC (E-UTRA-NR Dual Connectivity) for MR-DC in the case where the core network is EPCI04 and the master node is eNB102 (also known as extended eNB102) (options 7 and 7a described in Non-Patent Document 17); as NGEN-DC (NG-RAN E-UTRA-NR Dual Connectivity) for MR-DC in the case where the core network is 5GC110 and the master node is eNB102 (options 7 and 7a described in Non-Patent Document 17); and as E-UTRA / 5GC (option 5 described in Non-Patent Document 17) where eNB102 (extended eNB) uses 5GC as the core network. In this case, the RRC connection reconfiguration process can include not only LTE (E-UTRA) configuration information but also NR configuration information as described in Non-Patent Document 10. In addition, in this case, the RRC connection reset message can be sent from eNB102 to UE122 via gNB108.

[0086] Furthermore, the RRC reconfiguration process in MR-DC, particularly in the case of MR-DC with core network 5GC110 and master node gNB108, can be used for NE-DC (NR-E-UTRA Dual Connectivity) (options 4 and 4a described in Non-Patent Document 17). In this case, the RRC reconfiguration process can include not only NR configuration information but also LTE (E-UTRA) configuration information described in Non-Patent Document 10. In addition, in this case, the RRC reconfiguration message can be sent from gNB108 to UE122 via eNB102.

[0087] In the various embodiments of the present invention, to avoid cumbersome descriptions, the term "RRC reset process" is used for explanation, and gNB108 is used as the base station device for explanation. It should be noted that the names for architectures such as EN-DC, NGEN-DC, E-UTRA / 5GC, and NE-DC may also be different and referred to by other names.

[0088] During the RRC reconfiguration process, UE122 receives an RRC reconfiguration message (RRCReconfiguration) from gNB108 (step S400) and performs various settings based on the information included in the RRC reconfiguration message, such as radio bearer settings and SDAP settings (step S402). After step S402, UE122 can send an RRC reconfiguration completion message (RRCReconfigurationComplete) to gNB108 (not shown). It should be noted that the RRC reconfiguration message can also be called RRC reconfiguration, and the RRC reconfiguration completion message can also be called RRC reconfiguration completion.

[0089] Figure 5 This is a block diagram illustrating the configuration of the terminal device (UE122) according to various embodiments of the present invention. It should be noted that, to avoid unnecessary detail, in... Figure 5 Only the main components closely related to the present invention are shown.

[0090] Figure 5 The UE122 shown consists of a receiving unit 500 that receives RRC reset messages from gNB108 and a processing unit 502 that processes various information elements (IEs) and / or various fields and / or various conditions included in the received messages.

[0091] Figure 6This is a block diagram illustrating the configuration of a base station apparatus (gNB108) according to various embodiments of the present invention. It should be noted that, to avoid unnecessary detail, [the following is omitted as it is not part of the original text]. Figure 6 Only the main components closely related to the present invention are shown.

[0092] Figure 6 The gNB108 shown comprises a sending unit 600 that sends RRC reset messages to UE122, and a processing unit 602 that creates and sends RRC reset messages, including setting information such as various information elements (IEs), and / or various fields, and / or various conditions, to UE122, causing the processing unit 502 of UE122 to process them. It should be noted that... Figure 6 The configuration shown can also be applied to eNB102. When applied to eNB102, the message sent by the transmitting unit 600 to UE122 can be an RRC connection reset message.

[0093] Figure 7 This refers to Embodiment 1 of the present invention. Figure 4 This is an example of an ASN.1 (Abstract Syntax Notation One) description of information elements included in an RRC reset message. In 3GPP, ASN.1 is used in RRC specifications (Non-Patent Document 4, Non-Patent Document 10) to describe RRC messages and information elements (IEs). Figure 7 In the examples of ASN.1, <omitted> and <omitted in the middle> indicate the omission of other information, not the omission of a portion expressed by ASN.1. It should be noted that information elements may also be omitted where <omitted> or <omitted in the middle> are not explicitly stated. Figure 7 The example in ASN.1 does not correctly follow the ASN.1 representation method, but is instead an example of the RRC reset parameter in this invention; other names and expressions may also be used. Furthermore, Figure 7 In the example of ASN.1, to avoid being too verbose, only examples of key information closely related to the present invention are shown.

[0094] exist Figure 7 The information element represented by DRB-ToAddModList or DRBToAddMod can be a list of information indicating the addition or modification of DRB (data radio bearer) settings. In embodiments of the present invention, it is sometimes also referred to as radio bearer setting information element or data radio bearer information element.

[0095] The information element represented by DRB-Identity in the radio bearer configuration information element is the information of the DRB identifier of the added or modified DRB. In embodiments of the present invention, it is sometimes also referred to as the radio bearer identifier information element or the data radio bearer identifier information element. Figure 7 In the example, it is set to an integer value from 1 to 32, but other values ​​are also possible. In the case of DC, the DRB identifier is unique within the range of UE122.

[0096] The information element represented by cnAssociation in the radio bearer configuration information element can be an information element indicating whether EPC104 or 5GC110 is used in the core network. In embodiments of the present invention, it is sometimes also referred to as an association information element for the core network. That is, when UE122 is connected to EPC, DRB can be associated with EPS bearer identifier information element (eps-BearerIdentity) in cnAssociation or EPS bearer identifier as the value of EPS bearer identifier information element. When UE122 is connected to 5GC110, DRB can be associated with SDAP entity configured according to SDAP configuration information element (sdap-Config) described below, or PDU session information element included in SDAP configuration information element, or PDU session identifier as the value of PDU session information element or PDU session shown by PDU session information element. That is, the information represented by cnAssociation may include EPS bearer identifier information element (eps-BearerIdentity) in the case of using EPC104 in the core network when using EN-DC, and may include information element (sdap-Config) representing SDAP settings in the case of using 5GC110 in the core network, i.e., when not using EN-DC.

[0097] In the case of a core network of 5GC110, the information element represented by sdap-Config can be information about the setting or resetting of SDAP entities that determines the mapping (map) method between QoS flows and DRBs. In embodiments of the present invention, it is sometimes also referred to as SDAP setting information element.

[0098] The field or information element represented by pdu-session or PDU-SessionID included in the SDAP configuration information element may be the identifier of the PDU session to which the QoS flow corresponding to the value of the radio bearer identifier information element established in the radio bearer configuration information element including this SDAP configuration information element belongs, as described in Non-Patent Document 2. In embodiments of the present invention, it is sometimes also referred to as the PDU session information element. The value of the PDU session information element may be a non-negative integer.

[0099] The information element represented by mappedQoS-FlowsToAdd included in the SDAP configuration information element can be information from a list of QoS flow representations (QFI: QoS Flow Identity) information elements (described later) that represent QoS flows corresponding to or appending to the values ​​of the radio bearer identifier information elements corresponding to the values ​​of this SDAP configuration information element. In embodiments of the present invention, this is sometimes also referred to as an appended QoS flow information element. The aforementioned QoS flow can be the QoS flow of a PDU session shown in the PDU session information element included in this SDAP configuration information element.

[0100] Furthermore, the information element represented by mappedQoS-FlowsToRelease included in the SDAP configuration information element can be information about a list of QoS flows corresponding to the QoS flows in the QoS flows corresponding to the values ​​of the radio bearer identifier information elements included in this SDAP configuration information element, which is a list of QoS flow identifier (QFI: QoS Flow Identity) information elements described later. In embodiments of the present invention, this is sometimes also referred to as the released QoS flow information element. The aforementioned QoS flow can be the QoS flow of a PDU session shown in the PDU session information element included in this SDAP configuration information element.

[0101] The information element represented by QFI can be a QoS flow identifier, which uniquely identifies a QoS flow as described in Non-Patent Document 2. In embodiments of the present invention, it is sometimes referred to as a QoS flow identifier information element. The value of the QoS flow identifier information element can be a non-negative integer. Furthermore, the value of the QoS flow identifier information element can be unique for a PDU session.

[0102] In addition, the SDAP configuration information elements may include an uplink header information element indicating whether uplink data sent via the configured DRB contains an uplink SDAP header, a downlink header information element indicating whether downlink data received via the configured DRB contains a downlink SDAP header, and a default bearer information element indicating whether the configured DRB is the default radio bearer (default DRB).

[0103] Furthermore, the information element represented by pdcp-Config or PDCP-Config in the radio bearer configuration information element can be information about the configuration of the NR PDCP entity for establishing and modifying PDCP306 for SRB or DRB. In embodiments of the present invention, it is sometimes referred to as a PDCP configuration information element. Information related to the configuration of the NR PDCP entity may include information indicating the size of the uplink sequence number, information indicating the size of the downlink sequence number, information indicating the header compression (RoHC) profile, re-ordering timer information, etc.

[0104] Furthermore, the information element represented by DRB-ToReleaseList in the radio bearer configuration information element can be a list of DRB identifiers of the released DRBs. In embodiments of the present invention, it is sometimes also referred to as the released radio bearer information element or the released data radio bearer information element.

[0105] also, Figure 7 Some or all of the information elements shown may be optional. That is, Figure 7 The information elements shown can be included in the RRC reset message as needed or based on conditions.

[0106] use Figure 8 An example of the processing method of UE122 according to an embodiment of the present invention will be described.

[0107] The processing unit 602 of gNB108 creates an RRC reset message including radio bearer configuration information elements for enabling UE122 to process, and sends it to UE122 by the sending unit 600 (not shown). The receiving unit 500 of UE122 receives the RRC reset message from gNB108 (step S800). It should be noted that UE122 can also receive an RRC message including the aforementioned radio bearer configuration information elements from eNB102.

[0108] Next, the processing unit 502 of UE122 determines whether the value of the radio bearer identifier information element included in the radio bearer setting information element is set in UE122 and whether the radio bearer setting information element includes the SDAP setting information element. Based on the fact that the value of the radio bearer identifier information element included in the radio bearer setting information element is not set in UE122 and / or the radio bearer setting information element includes the SDAP setting information element, the processing of step S804 described below (step S802) is performed.

[0109] The processing unit 502 of UE122 determines whether the SDAP entity corresponding to the PDU session shown in the PDU session information element included in the above-mentioned SDAP setting information element exists. Based on the fact that the SDAP entity corresponding to the PDU session shown in the PDU session information element included in the above-mentioned SDAP setting information element does not exist, the processing of step S806 and / or step S808 is performed (step S804).

[0110] The processing unit 502 of UE122 establishes an SDAP entity (step S806). It should be noted that a DRB corresponding to the value of the aforementioned Radio Bearer Identifier information element can be established by establishing a PDCP entity or similar entity before establishing the SDAP entity. It should also be noted that the SDAP entity can be further set or reset after its establishment. Furthermore, when setting or resetting the SDAP entity, a relationship can be established between the established DRB and the SDAP entity.

[0111] The processing unit 502 of UE122 determines whether the SDAP entity corresponding to the PDU session existed before receiving the RRC reset message. Based on the fact that the SDAP entity corresponding to the PDU session did not exist before receiving the RRC reset message, it notifies the upper layer that "user-plane resources for the PDU session have been established" (step S808). It should be noted that "user-plane resources for the PDU session have been established" can also be expressed as "user-plane resources for the PDU session have been configured" or other similar expressions.

[0112] "User plane resources established for the above-mentioned PDU session" can also be expressed as "the QoS flow and radio bearer correspondence rules stored with the values ​​of the QoS flow identifier information elements or QoS flow identifier information elements included in the additional QoS flow information elements included in the above-mentioned SDAP configuration information elements".

[0113] The notification "User plane resources for the aforementioned PDU session have been established" could, for example, be an upward notification of the aforementioned PDU session identifier information element or the value of the PDU session identifier information element. Furthermore, at this time, the upward notification of the aforementioned QoS flow identifier information element or the value of the QoS flow identifier information element can be performed simultaneously, or the upward notification of the aforementioned QoS flow identifier information element or the value of the QoS identifier information element can be used instead of an upward notification of the aforementioned PDU session identifier information element or the value of the aforementioned PDU session identifier information element.

[0114] Furthermore, "determining whether the SDAP entity corresponding to the PDU session existed before receiving the aforementioned RRC reset message" can also be interpreted as "determining whether the establishment of the aforementioned SDAP entity (in step S806) resulted in a full setup." Additionally, "based on the fact that the SDAP entity corresponding to the PDU session did not exist before receiving the aforementioned RRC reset message" can also be interpreted as "based on the fact that the establishment of the aforementioned SDAP entity (in step S806) was not a full setup."

[0115] Furthermore, in step S808, "the SDAP entity corresponding to the PDU session did not exist before receiving the aforementioned RRC reset message" can also be expressed as "the SDAP entity corresponding to the PDU session existed before receiving the aforementioned RRC reset message," and other than the condition (else). Furthermore, "the establishment of the SDAP entity (in step S806) was not the result of a full reset" can also be expressed as "the establishment of the SDAP entity (in step S806) was the result of a full reset," and other than the condition (else).

[0116] Next use Figure 9 Another example of the processing method of UE122 according to an embodiment of the present invention will be described.

[0117] The processing unit 602 of gNB108 creates an RRC reset message including radio bearer configuration information elements for enabling UE122 to process, and sends it to UE122 by the sending unit 600 (not shown). The receiving unit 500 of UE122 receives the RRC reset message from gNB108 (step S900). It should be noted that UE122 can also receive an RRC message including the aforementioned radio bearer configuration information elements from eNB102.

[0118] Next, the processing unit 502 of UE122 determines whether the value of the radio bearer identifier information element included in the radio bearer setting information element is set in UE122 and whether the radio bearer setting information element includes the SDAP setting information element. Based on the fact that the value of the radio bearer identifier information element included in the radio bearer setting information element is not set in UE122 and / or the radio bearer setting information element includes the SDAP setting information element, the processing of step S904 described below (step S902) is performed.

[0119] The processing unit 502 of UE122 determines whether the SDAP entity corresponding to the PDU session shown in the PDU session information element included in the above-mentioned SDAP setting information element exists. Based on the fact that the SDAP entity corresponding to the PDU session shown in the PDU session information element included in the above-mentioned SDAP setting information element does not exist, the processing of step S906 and / or step S908 described below (step S904) is performed.

[0120] The processing unit 502 of UE122 establishes an SDAP entity (step S806). It should be noted that a DRB corresponding to the value of the aforementioned Radio Bearer Identifier information element can be established by establishing a PDCP entity or similar entity before establishing the SDAP entity. It should also be noted that the SDAP entity can be further set or reset after its establishment. Furthermore, when setting or resetting the SDAP entity, a relationship can be established between the established DRB and the SDAP entity.

[0121] The processing unit 502 of UE122 determines whether the SDAP entity corresponding to the PDU session existed before receiving the RRC reset message. Based on the existence of the SDAP entity corresponding to the PDU session before receiving the RRC reset message, the SDAP entity established in step S906 is associated with the PDU session (step S908).

[0122] Furthermore, "determining whether the SDAP entity corresponding to the PDU session existed before receiving the aforementioned RRC reset message" can also be interpreted as "determining whether the establishment of the aforementioned SDAP entity (in step S906) resulted in a full setting." Additionally, "based on the existence of the SDAP entity corresponding to the PDU session before receiving the aforementioned RRC reset message" can also be interpreted as "based on the establishment of the aforementioned SDAP entity (in step S906) being a full setting result."

[0123] Furthermore, in step S908, "the SDAP entity corresponding to the PDU session existed before receiving the aforementioned RRC reset message" can also be interpreted as "the SDAP entity corresponding to the PDU session did not exist before receiving the aforementioned RRC reset message," or any other condition (else). Furthermore, "the establishment of the SDAP entity (in step S906) is the result of a full reset" can also be interpreted as "the establishment of the SDAP entity (in step S806) is not the result of a full reset," or any other condition (else).

[0124] It should be noted that, in embodiments of the present invention, the process of notifying the upper layer that "user-plane resources for the PDU session corresponding to the aforementioned PDU session information element have been established or configured" can be performed by RRC308 or RRC208, or by SDAP310. Furthermore, the upper layer notifying that "user-plane resources for the PDU session corresponding to the aforementioned PDU session information element have been established or configured" can be the NAS layer. Additionally, the notification to the upper layer that "user-plane resources for the PDU session corresponding to the aforementioned PDU session information element have been established or configured" can be performed after RRC308 or RRC208 confirms that the QoS flow and radio bearer correspondence establishment rules corresponding to the values ​​of the QoS flow identifier information elements or QoS flow identifier information elements included in the additional QoS flow information elements included in the aforementioned radio bearer configuration information elements are stored in SDAP310. The method for confirming that the above-mentioned corresponding establishment rules have been stored can be a notification from SDAP310 to RRC308 or RRC208 indicating that the corresponding establishment rules have been stored.

[0125] Thus, in the embodiments of the present invention, by notifying the upper layer of the established or configured user plane resources for the PDU session when a new PDU session is established during the establishment of an SDAP entity, the upper layer can detect the user plane resources established for the PDU session at the lower layer, and user data can be sent at the optimal timing. That is, the terminal device can reduce the complexity of protocol processing and perform communication efficiently.

[0126] It should be noted that the wireless bearer settings in the various embodiments of the present invention can include not only the RRC connection reset process, but also the RRC Establishment process and the RRC Re-Establishment process. Furthermore, the wireless bearer in the various embodiments of the present invention can be a DRB or an SRB.

[0127] It should be noted that the "information element" in the various embodiments of the present invention can also be referred to as a "field".

[0128] Furthermore, in various embodiments of the present invention, the notification to the upper layer that "user-plane resources for a PDU session corresponding to the PDU session information element have been established" and / or "user-plane resources for a PDU session corresponding to the PDU session information element have been established or set" may be other information, except for the wording variations in the various embodiments of the present invention.

[0129] Furthermore, in various embodiments of the present invention, "the radio bearer configuration information element includes the SDAP configuration information element" can mean that EN-DC is not used, i.e., the opposite of using EN-DC. This is because, as described in Non-Patent Document 8 and Non-Patent Document 9, in NR (New Radio technology), EPC is used as the core network only in the case of EN-DC.

[0130] Furthermore, the processing and methods of the terminal device and base station device described in the various embodiments of the present invention can be summarized as follows, for example.

[0131] A terminal device for communicating with a base station device includes: a receiving unit that receives an RRC reset message including radio bearer setting information elements from the base station device; and a processing unit that, based on the fact that the value of the radio bearer identifier information element included in the radio bearer setting information element and the fact that the radio bearer setting information element includes an SDAP setting information element, and that an SDAP entity for the PDU session information element included in the SDAP setting information element does not exist in the settings of the terminal device, establishes an SDAP entity, and determines whether an SDAP entity for the PDU session information element existed before receiving the RRC reset message; based on the fact that an SDAP entity for the PDU session information element did not exist before receiving the RRC reset message, notifies an upper layer that user plane resources for the PDU session corresponding to the value of the PDU session information element have been set; and based on the fact that an SDAP entity for the PDU session information element existed before receiving the RRC reset message, establishes a relationship between the established SDAP entity and the PDU session.

[0132] Furthermore, a base station apparatus for communicating with a terminal device includes: a transmitting unit that transmits an RRC reset message including radio bearer setting information elements to the terminal device; and a processing unit that, in the RRC reset message including radio bearer setting information elements, causes the terminal device to perform processing, the processing being as follows: based on the fact that the value of the radio bearer identifier information element included in the radio bearer setting information element does not exist in the settings of the terminal device and that the radio bearer setting information element includes an SDAP setting information element, and that an SDAP entity for the PDU session information element included in the SDAP setting information element does not exist, an SDAP entity is established; furthermore, based on the fact that the SDAP entity for the PDU session information element does not exist before receiving the RRC reset message, a notification is sent to an upper layer that user plane resources for the PDU session corresponding to the value of the PDU session information element have been set; and based on the fact that the SDAP entity for the PDU session information element exists before receiving the RRC reset message, a relationship is established between the established SDAP entity and the PDU session.

[0133] Furthermore, a method for a terminal device communicating with a base station device includes receiving an RRC reset message from the base station device, comprising: receiving an RRC reset message including radio bearer configuration information elements; establishing an SDAP entity based on the fact that the value of a radio bearer identifier information element included in the radio bearer configuration information element and an SDAP configuration information element included in the radio bearer configuration information element do not exist in the settings of the terminal device, and in the case that an SDAP entity for a PDU session information element included in the SDAP configuration information element does not exist; determining whether an SDAP entity for the PDU session information element existed before receiving the RRC reset message; notifying an upper layer that user plane resources for a PDU session corresponding to the value of the PDU session information element have been configured based on the fact that an SDAP entity for the PDU session information element did not exist before receiving the RRC reset message; and establishing a relationship between the established SDAP entity and the PDU session based on the fact that an SDAP entity for the PDU session information element existed before receiving the RRC reset message.

[0134] Furthermore, a method for a base station device communicating with a terminal device includes sending an RRC reset message to the terminal device, the RRC reset message including radio bearer configuration information elements, causing the terminal device to process the following: Based on the fact that the value of the radio bearer identifier information element included in the radio bearer configuration information element and the fact that the radio bearer configuration information element includes an SDAP configuration information element in the radio bearer configuration information element do not exist in the settings of the terminal device, and that the SDAP entity for the PDU session information element included in the SDAP configuration information element does not exist, an SDAP entity is established; furthermore, it is determined whether the SDAP entity for the PDU session information element existed before receiving the RRC reset message; based on the fact that the SDAP entity for the PDU session information element did not exist before receiving the RRC reset message, the upper layer is notified that user plane resources for the PDU session corresponding to the value of the PDU session information element have been configured; based on the fact that the SDAP entity for the PDU session information element existed before receiving the RRC reset message, a relationship is established between the established SDAP entity and the PDU session.

[0135] The program operating in the apparatus of the present invention can be a program that controls the Central Processing Unit (CPU) or similar components to enable the computer to perform its functions in a manner that achieves the functions described in the embodiments of the present invention. During processing, the program or the information processed by the program is temporarily read into volatile memory such as Random Access Memory (RAM) or stored in non-volatile memory such as Flash Memory or Hard Disk Drive (HDD), and is read, modified, and written by the CPU as needed.

[0136] It should be noted that a portion of the device described in the above embodiments can be implemented using a computer. In this case, the program for implementing the control function can be recorded on a computer-readable recording medium, and the control function can be implemented by reading the program recorded on the recording medium into a computer system and executing it. Here, "computer system" refers to a computer system built into the device, and is configured to include hardware such as an operating system and peripherals. Furthermore, the "computer-readable recording medium" can be any of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, etc.

[0137] Furthermore, a "computer-readable recording medium" may also include: a medium that dynamically stores a program for a short period of time, such as a communication line in the case of transmitting a program via a network such as the Internet or a communication line such as a telephone line; and a medium that retains a program for a certain period of time, such as volatile memory within a computer system that serves as a server or client in this case. In addition, the program may be a program used to implement the functions described above, or it may be a program that can implement the functions described above by combining with programs already recorded in the computer system.

[0138] Furthermore, the functional blocks or features of the apparatus used in the above embodiments can be implemented or executed by circuits, typically by integrated circuits or multiple integrated circuits. Circuits designed to perform the functions described in this specification may include: general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic elements, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general-purpose processor may be a microprocessor, or alternatively, a conventional processor, controller, microcontroller, or state machine. The general-purpose processor or the circuits described above may be constructed from digital circuits or analog circuits. Furthermore, in cases where advancements in semiconductor technology have led to the development of integrated circuit technologies that replace existing integrated circuits, integrated circuits based on such technologies may also be used.

[0139] It should be noted that the invention of this application is not limited to the embodiments described above. While one example of the device is described in the embodiments, the invention of this application is not limited thereto and can be applied to fixed or non-movable electronic devices installed indoors or outdoors, such as AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other terminal devices or communication devices for daily life.

[0140] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the specific configuration is not limited to these embodiments, and design changes that do not depart from the spirit of the present invention are also included. Furthermore, the present invention can be modified in various ways within the scope of the technical solutions shown, and embodiments obtained by appropriately combining technical solutions disclosed in different embodiments are also included within the technical scope of the present invention. In addition, it also includes configurations obtained by replacing elements that have the same effect as those described in the above embodiments with each other.

[0141] Industrial availability

[0142] One aspect of the present invention can be used, for example, in communication systems, communication devices (e.g., mobile phone devices, base station devices, wireless LAN devices, or sensor devices), integrated circuits (e.g., communication chips), or programs.

Claims

1. A terminal device for communicating with a base station device, the terminal device comprising: A receiving unit, configured to receive from the base station device a Radio Resource Control (RRC) reset message including a Data Radio Bearer (DRB) setting; and Processing department, in which The processing unit is configured to: It is determined that a) the DRB identifier included in the DRB settings does not exist in the current settings of the terminal device; b) the DRB settings include Service Data Adaptation Protocol (SDAP) settings; and c) the SDAP entity corresponding to the PDU session indicated by the Protocol Data Unit (PDU) session information element included in the SDAP settings does not exist. In the case where the processing unit determines a), b), and c), Establish SDAP entities, and Further, it was determined that d) the SDAP entity corresponding to the PDU session indicated by the PDU session information element did not exist before the RRC reset message was received, and Based on the fact that the SDAP entity corresponding to the PDU session indicated by the PDU session information element did not exist before the RRC reset message was received. The upper layer is notified that a user plane resource for the PDU session information element has been established.

2. A communication method used by a terminal device communicating with a base station device, the communication method comprising the following steps: Receive from the base station device a Radio Resource Control (RRC) reset message including the Data Radio Bearer (DRB) setting; When processing a received RRC reset message, it is determined that a) the DRB identifier included in the DRB setting does not exist in the current setting of the terminal device; b) the DRB setting includes a Service Data Adaptation Protocol (SDAP) setting; and c) the SDAP entity corresponding to the PDU session indicated by the Protocol Data Unit (PDU) session information element included in the SDAP setting does not exist. Given that a), b), and c) are determined Establish SDAP entities, and Further, it was determined that d) the SDAP entity corresponding to the PDU session indicated by the PDU session information element did not exist before the RRC reset message was received. Based on the fact that the SDAP entity corresponding to the PDU session indicated by the PDU session information element did not exist before the RRC reset message was received. The upper layer is notified that a user plane resource for the PDU session information element has been established.

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