Terminal device, method and integrated circuit

Abstract

The present invention is a terminal device for communicating with a base station device, the terminal device comprising a receiving unit for receiving an RRC reconfiguration message from the base station device; and a processing unit for establishing a PDCP entity according to the RRC reconfiguration message, applying a first encryption algorithm, a first encryption key, a first integrity protection algorithm and a first integrity protection key provided by an upper layer to the PDCP entity, and based on a first request made by the upper layer, applying a second encryption algorithm, a second encryption key, a second integrity protection algorithm and a second integrity protection key provided by the upper layer to the PDCP entity.

Description

Technical Field

[0001] The present invention relates to a terminal device, a method and an integrated circuit.

[0002] This application claims priority to Japanese Patent Application No. 2019-131999 filed in Japan on July 17, 2019, the contents of which are incorporated herein by reference. Background Art

[0003] In the 3rd Generation Partnership Project (3GPP), research is being conducted on wireless access methods and wireless 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)") for cellular mobile communications. EUTRA is also known as E-UTRA.

[0004] In addition, 3GPP has conducted technical research and standardization on LTE-Advanced Pro, an extension technology of LTE, and NR (New Radiotechnology), a new radio access technology, as wireless access methods and wireless network technologies for the fifth generation cellular system (Non-Patent Document 1). In addition, 5GC (5 Generation Core Network), a core network for the fifth generation cellular system, has also been studied (Non-Patent Document 2).

[0005] Prior art literature

[0006] Non-patent literature

[0007] Non-patent document 1: 3GPP RP-170855, “Work Item on New Radio (NR) Access Technology”

[0008] Non-patent document 2: 3GPP TS 23.501 v15.3.0, “System Architecture for the 5G System; Stage 2”

[0009] Non-patent document 3: 3GPP TS 36.300, v15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA) and Evolved Universal Terestrial Radio Access Network (E-UTRAN); Overall description; Stage 2"

[0010] Non-patent document 4: 3GPP TS 36.331 v15.4.0, “Evolved Universal Terestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specifications”

[0011] Non-patent document 5: 3GPP TS 36.323 v15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Packet Data Convergence Protocol (PDCP) specification"

[0012] Non-patent document 6: 3GPP TS 36.322 v15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Radio Link Control (RLC) protocol specification"

[0013] Non-patent document 7: 3GPP TS 36.321 v15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification"

[0014] Non-patent document 8: 3GPP TS 37.340v 15.3.0, "Evolved Universal Terestrial Radio Access (E-UTRA) and NR; Multi-Connectivity; Stage 2"

[0015] Non-patent document 9: 3GPP TS 38.300v 15.3.0, “NR; NR and NG-RAN Overall description; Stage 2”

[0016] Non-Patent Document 10: 3GPP TS 38.331 v15.4.0, “NR; Radio Resource Control (RRC); Protocol specifications”

[0017] Non-patent document 11: 3GPP TS 38.323 v15.3.0, “NR; Packet Data Convergence Protocol (PDCP) specification”

[0018] Non-Patent Document 12: 3GPP TS 38.322 v15.3.0, “NR; Radio Link Control (RLC) protocol specification”

[0019] Non-Patent Document 13: 3GPP TS 38.321 v15.3.0, “NR; Medium Access Control (MAC) protocol specification”

[0020] Non-Patent Document 14: 3GPP TS 23.401 v15.0.0, "General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access"

[0021] Non-Patent Document 15: 3GPP TS 23.502 v15.3.0, “Procedure for 5G System; Stage 2”

[0022] Non-Patent Document 16: 3GPP TS 37.324 v15.1.0, “NR; Service Data Adaptation Protocol (SDAP) specification”

[0023] Non-Patent Document 17: 3GPP Draft_Report_v1.doc, “Report of 3GPP TSG RAN2#105meeting, Athens, Greece” http: / / www.3gpp.org / ftp / TSG_RAN / WG2_RL2 / TSGR2_105 / Report / Draft_Report_v1.zip

[0024] Non-Patent Document 18: 3GPP RP-181544, “Revised WID: Even further mobility enhancement in E-UTRAN”

[0025] Non-Patent Document 19: 3GPP RP-181433, “New WID: NR mobility enhancements”

[0026] Non-Patent Document 20: 3GPP R2-1901364, “Detail for non-split bearer option for simultaneous connectivity” Summary of the invention

[0027] Problem that the invention aims to solve

[0028] As one of the technical studies of LTE, the mechanism for further extending the existing LTE mobility extension technology is studied. Moreover, in the technical research of NR, the mechanism for extending the existing NR mobility technology is also studied. (Non-patent literature 18, 19). These studies mainly include: research on technology that makes the interruption of user data transmission and reception close to 0ms when moving between cells in which the base station device and the terminal device are connected (during switching) (RUDI: Reduce User Data Interruption); and research on improvements in the robustness of switching (Handover robustness improvements).

[0029] In RUDI, a mechanism for coexistence of two protocol stacks for one cell group has been studied, but detailed terminal operations for efficiently controlling mobility have not been studied yet.

[0030] An aspect of the present invention is made in view of the above-mentioned problem, and one of its objects is to provide a terminal device, method, and integrated circuit that can efficiently control mobility.

[0031] Technical Solution

[0032] In order to achieve the above-mentioned object, one solution of the present invention adopts the following solution. That is, a terminal device communicating with a base station device comprises: a receiving unit, receiving an RRC reconfiguration message from the base station device; and a processing unit, the processing unit establishing a PDCP entity according to the RRC reconfiguration message, applying a first encryption algorithm, a first encryption key, a first integrity protection algorithm and a first integrity protection key provided by an upper layer to the PDCP entity, and applying a second encryption algorithm, a second encryption key, a second integrity protection algorithm and a second integrity protection key provided by the upper layer to the PDCP entity based on a first request made by the upper layer.

[0033] In addition, one embodiment of the present invention is a method for a terminal device communicating with a base station device, wherein an RRC reconfiguration message is received from the base station device, a PDCP entity is established according to the RRC reconfiguration message, a first encryption algorithm, a first encryption key, a first integrity protection algorithm and a first integrity protection key provided by an upper layer are applied to the PDCP entity, and based on a first request made by the upper layer, a second encryption algorithm, a second encryption key, a second integrity protection algorithm and a second integrity protection key provided by the upper layer are applied to the PDCP entity.

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

[0035] Beneficial Effects

[0036] According to an aspect of the present invention, a terminal device can implement efficient mobility processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of a communication system according to each embodiment of the present invention.

[0038] Figure 2 This is a protocol stack diagram of UP and CP of a terminal device and a base station device in E-UTRA according to each embodiment of the present invention.

[0039] Figure 3 It is a protocol stack diagram of UP and CP of the terminal device and base station device in NR of each embodiment of the present invention.

[0040] Figure 4 This is a diagram showing an example of the flow of procedures for various settings in RRC208 and / or RRC308 according to each embodiment of the present invention.

[0041] Figure 5 It is a block diagram showing the configuration of a terminal device according to each embodiment of the present invention.

[0042] Figure 6 It is a block diagram showing the configuration of a base station apparatus according to each embodiment of the present invention.

[0043] Figure 7 This is an example of processing related to handover in EUTRA according to each embodiment of the present invention.

[0044] Figure 8 This is an example of processing related to switching in NR of each embodiment of the present invention.

[0045] Fig. 9 This is an example of the start and stop conditions of each timer in the embodiment of the present invention.

[0046] Fig.10 It is an example of the mobilityControlInfo information element of an embodiment of the present invention.

[0047] Fig.11 is another example of the mobilityControlInfo information element of an embodiment of the present invention.

[0048] Fig.12 It is an example of a synchronization resetting information element of an embodiment of the present invention.

[0049] Fig.13 is another example of a synchronization resetting information element according to an embodiment of the present invention.

[0050] Fig.14 This is an example of an ASN.1 description included in a message related to the re-establishment of an RRC connection in an NR according to an embodiment of the present invention.

[0051] Fig.15 This is an example of an ASN.1 description included in a message related to re-establishment of an RRC connection in E-UTRA according to an embodiment of the present invention.

[0052] Fig.16 This is a diagram showing an example of the flow of process A according to the embodiment of the present invention.

[0053] Fig.17 This is a diagram showing an example of the flow of process B according to the embodiment of the present invention.

[0054] Fig.18 This is a diagram showing an example of the flow of process C according to the embodiment of the present invention.

[0055] Fig.19 This is a diagram showing an example of the flow of the process H according to the embodiment of the present invention.

[0056] Fig. 20 This is an example of ASN.1 description of parameters for setting whether to apply Make-Before-Break switching to a radio bearer according to each embodiment of the present invention.

[0057] Fig.21 This is another example of ASN.1 description of parameters for setting whether to apply make-before-break switching to a radio bearer according to each embodiment of the present invention.

[0058] Fig. 22 It is a block diagram showing the configuration of a protocol set in UE 122 according to each embodiment of the present invention.

[0059] Fig.23 This is an example of a processing method of each form of the PDCP entity 2200 of this embodiment.

[0060] Fig.24 This is an example of a downlink reception processing method of the PDCP entity 2200 in each form of this embodiment.

[0061] Fig.25 This is an example of an uplink transmission processing method of each form of the PDCP entity 2200 of this embodiment.

[0062] Fig.26 This is another example of the processing method of the PDCP entity 2200 in various forms of this embodiment.

[0063] Fig. 27 This is a diagram showing another example of the flow of the process E according to the embodiment of the present invention.

[0064] Fig.28 This is a diagram showing another example of the flow of process B according to the embodiment of the present invention.

[0065] Fig.29 This is a diagram showing another example of the flow of processing LA according to the embodiment of the present invention. DETAILED DESCRIPTION

[0066] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0067] LTE (and LTE-A Pro) and NR can be defined as different radio access technologies (Radio Access Technology: RAT). In addition, NR can be defined as a technology included in LTE. LTE can be defined as a technology included in NR. In addition, LTE that can be connected to NR through multi-radio dual connectivity can be distinguished from existing LTE. In addition, LTE with a core network of 5GC can be distinguished from existing LTE with a core network of EPC. This embodiment can be applied to NR, LTE, and other RATs. In the following description, terms associated with LTE and NR are used for description, but it can also be applied to other technologies using other terms. In addition, the term E-UTRA in this embodiment can be replaced with a term called LTE, and the term LTE can be replaced with a term called E-UTRA.

[0068] Figure 1 It is a schematic diagram of a communication system according to each embodiment of the present invention.

[0069] E-UTRA100 is a radio access technology described in non-patent document 3, etc., and includes a cell group (Cell Group: CG) composed of one or more frequency bands. eNB (E-UTRAN Node B: E-UTRAN Node B) 102 is a base station device of E-UTRA100. EPC (Evolved Packet Core: Evolved Packet Core) 104 is a core network described in non-patent document 14, etc., and is designed as a core network for E-UTRA100. Interface 112 is an interface between eNB102 and EPC104, and there are a control plane (Control Plane: CP) through which control signals pass and a user plane (User Plane: UP) through which user data passes.

[0070] NR106 is a wireless access technology described in non-patent document 9, etc., and includes a cell group (Cell Group: CG) composed of one or more frequency bands. gNB (g Node B: g Node B) 108 is a base station device of NR106. 5GC110 is a core network described in non-patent document 2, etc., which is designed as a core network for NR106, but can also be used as a core network for E-UTRA100 with a function of connecting to 5GC110. The following E-UTRA100 may include E-UTRA100 with a function of connecting to 5GC110.

[0071] Interface 114 is an interface between eNB102 and 5GC110, interface 116 is an interface between gNB108 and 5GC110, interface 118 is an interface between gNB108 and EPC104, interface 120 is an interface between eNB102 and gNB108, and interface 124 is an interface between EPC104 and 5GC110. Interface 114, interface 116, interface 118, interface 120, and interface 124 can be interfaces only through CP or only through UP, or through both CP and UP. In addition, interface 114, interface 116, interface 118, interface 120, and interface 124 may not exist depending on the communication system provided by the communication operator.

[0072] UE122 is a terminal device corresponding to any one or all of E-UTRA100 and NR106. As described in any one or all of non-patent document 3 and non-patent document 9, when UE122 is connected to the core network via any one or all of E-UTRA100 and NR106, a logical path called a radio bearer (RB: Radio Bearer) is established between UE122 and any one or all of E-UTRA100 and NR106. The radio bearer used for CP is called a signaling radio bearer (SRB: Signaling Radio Bearer), and the radio bearer used for UP is called a data radio bearer (DRB Data Radio Bearer). Each RB is assigned an RB identifier (RB Identity or RB ID) and is identified as unique. The RB identifier for SRB is called an SRB identifier (SRB Identity or SRB ID), and the RB identifier for DRB is called a DRB identifier (DRB Identity or DRB ID).

[0073] As described in non-patent document 3, when the core network of the connection destination of UE 122 is EPC 104, each DRB established between UE 122 and any one or all of E-UTRA 100 and NR 106 is further uniquely associated with each EPS (Evolved Packet System) bearer passing through EPC 104. Each EPS bearer is assigned an EPS bearer identifier (Identity or ID) and is uniquely identified. In addition, the same QoS is guaranteed for data passing through the same EPS bearer.

[0074] As described in non-patent document 9, when the connection destination core network of UE122 is 5GC110, one or more DRBs established between UE122 and any or all of E-UTRA100 and NR106 are further associated with one of the PDU (Packet Data Unit) sessions to be established in 5GC110. There are one or more QoS flows in each PDU session. Each DRB may be mapped to one or more QoS flows in the associated PDU session, or may not be mapped to any QoS flow. Each PDU session is identified by a PDU session identifier (Identity or ID). In addition, each QoS flow is identified by a QoS flow identifier. In addition, the same QoS is guaranteed for data passing through the same QoS flow.

[0075] There is no PDU session or QoS flow in EPC104, and there is no EPS bearer in 5GC110. In other words, when UE122 is connected to EPC104, UE122 has information about EPS bearers, and when UE122 is connected to 5GC110, UE122 has information about PDU sessions or QoS flows.

[0076] Figure 2 This is a diagram of a protocol stack of UP and CP of a terminal device and a base station device in an E-UTRA radio access layer according to each embodiment of the present invention.

[0077] Figure 2 (A) is a protocol stack diagram of UP used when UE 122 communicates with eNB 102 in E-UTRA 100.

[0078] PHY (Physical layer) 200 is a radio physical layer that provides transmission services to the upper layer using a physical channel. PHY 200 is connected to the upper 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 is sent and received between the PHY of UE 122 and eNB 102 via a wireless physical channel.

[0079] MAC202 is a medium access control layer that maps multiple logical channels to multiple transmission channels. MAC202 is connected to the upper RLC (Radio Link Control layer) 204 described later through logical channels. Logical channels are roughly classified according to the type of information transmitted, and are divided into control channels for transmitting control information and service channels for transmitting user information. MAC202 has the function of controlling PHY200 for intermittent transmission and reception (DRX / DTX), the function of executing the random access (Random Access) process, the function of notifying the transmission power information, and the function of performing HARQ control, etc. (Non-patent document 7).

[0080] RLC204 is a radio link control layer that segments the data received from the upper PDCP (Packet Data Convergence Protocol Layer) 206 described later and adjusts the data size so that the lower layer can properly send data. In addition, RLC200 also has a function for guaranteeing the QoS (Quality of Service) requested by each data. In other words, RLC204 has functions such as data retransmission control (Non-Patent Document 6).

[0081] PDCP206 is a Packet Data Convergence Protocol layer for efficiently transmitting IP packets (IP Packets) as user data in a wireless section. PDCP206 can have a header compression function for compressing unnecessary control information. In addition, PDCP206 can also have a data encryption function. (Non-patent document 5).

[0082] 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. In addition, the data transferred from the upper layer to MAC202, RLC204, and PDCP206 or the data transferred to the upper layer are respectively referred to as MAC SDU (Service Data Unit), RLC SDU, and PDCP SDU.

[0083] In addition, in order to distinguish between data and control, PDCP PDU can also be called PDCP DATA PDU (PDCP data PDU) and PDCP CONTROL PDU (PDCP control PDU). In addition, in order to distinguish between data and control, RLC PDU can also be called RLC DATA PDU (RLC data PDU) and RLC CONTROL PDU (RLC control PDU).

[0084] Figure 2 (B) is a protocol stack diagram of CP used when UE 122 communicates with eNB 102 and MME (Mobility Management Entity) which is a logical node providing functions such as authentication and mobility management in E-UTRA 100.

[0085] In the protocol stack of CP, in addition to PHY200, MAC202, RLC204, and PDCP206, there are also RRC (Radio Resource Control layer) 208 and NAS (non Access Strarum) 210. RRC208 is a radio link control layer that performs processes such as establishment, re-establishment, suspension, and resumption of RRC connections, re-setting of RRC connections, such as establishment, change, and release of radio bearers (Radio Bearer: RB) and cell groups (Cell Group), and controls logical channels, transport channels, and physical channels, as well as settings for switching and measurement (Measurement). RB can be divided into signaling radio bearers (Signaling Radio Bearer: SRB) and data radio bearers (Data Radio Bearer: DRB). SRB can be used as a path for sending RRC messages as control information. DRB can be used as a path for sending user data. Each RB can be set between the eNB 102 and the RRC 208 of the UE 122. In addition, the portion of the RB composed of the RLC 204 and the MAC 202 can also be referred to as an RLC bearer (Non-Patent Document 4). In addition, with respect to the NAS layer that carries the signal between the MME and the UE 122, a part or all of the layers of the PHY 200, MAC 202, RLC 204, PDCP 206, and RRC 208 that carry the signal and data between the UE 122 and the eNB 102 can be referred to as the AS (Access Strarum) layer.

[0086] The functional classification of MAC 202 , RLC 204 , PDCP 206 , and RRC 208 described above is an example, and part or all of each function may not be implemented. In addition, part or all of the functions of each layer may be included in other layers.

[0087] It should be noted that the IP layer and the TCP (Transmission Control Protocol) layer, UDP (User Datagram Protocol) layer, and application layer, which are layers above the IP layer, are upper layers of the PDCP layer (not shown). In addition, the RRC layer and NAS (non Access Strarum) layer are also upper layers of the PDCP layer (not shown). In other words, the PDCP layer is a lower layer of the RRC layer, NAS layer, IP layer, and the TCP (Transmission Control Protocol) layer, UDP (User Datagram Protocol) layer, and application layer, which are layers above the IP layer.

[0088] Figure 3 It is a protocol stack diagram of UP and CP of the terminal device and base station device in the NR wireless access layer of each embodiment of the present invention.

[0089] Figure 3 (A) is a protocol stack diagram of UP used when UE122 communicates with gNB108 in NR106.

[0090] PHY (Physical layer) 300 is the radio physical layer (Radio Physical layer) of NR, which can provide transmission services to the upper layer using the physical channel (Physical Channel). PHY300 can be connected to the upper MAC (Medium Access Control layer) 302 described later through the transport channel (Transport Channel). Data can be moved between MAC302 and PHY300 via the transport channel. Data can be sent and received between UE122 and gNB108's PHY via the wireless physical channel.

[0091] Here, the physical channel is described.

[0092] The following physical channels can be used in wireless communication between a terminal device and a base station device.

[0093] PBCH (Physical Broadcast Channel)

[0094] PDCCH (Physical Downlink Control Channel)

[0095] PDSCH (Physical Downlink Shared Channel)

[0096] PUCCH (Physical Uplink Control Channel)

[0097] PUSCH (Physical Uplink Shared Channel)

[0098] PRACH (Physical Random Access Channel)

[0099] PBCH is used to broadcast system information required by terminal devices.

[0100] In addition, in NR, PBCH can be used to broadcast the time index (SSB-Index) within the period of the block of synchronization signals (also called SS / PBCH block).

[0101] PDCCH is used to send (or transport) downlink control information (Downlink Control Information: DCI) in downlink wireless communication (wireless communication from the base station device 3 to the terminal device). Here, one or more DCIs (also referred to as DCI formats) are defined for the transmission of downlink control information. That is, the field for the downlink control information is defined as DCI and mapped to information bits. PDCCH is sent in PDCCH candidates. The terminal device monitors a set of PDCCH candidates in the serving cell. Monitoring means attempting to decode the PDCCH according to a certain DCI format. A certain DCI format can be used for scheduling PUSCH in the serving cell. PUSCH can be used for sending user data, sending RRC messages, etc.

[0102] PUCCH can be used to send uplink control information (Uplink Control Information: UCI) in uplink wireless communication (wireless communication from a terminal device to a base station device). Here, the uplink control information may include channel state information (CSI: Channel State Information) for indicating the state of a downlink channel. In addition, the uplink control information may include a scheduling request (SR: Scheduling Request) for requesting UL-SCH resources. In addition, the uplink control information may include HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement: Hybrid Automatic Repeat request acknowledgment).

[0103] The PDSCH can be used to transmit downlink data (DL-SCH: Downlink Shared CHannel) from the MAC layer. In addition, in the case of downlink, it is also used to transmit system information (SI: System Information), random access response (Random Access Response: RAR), etc.

[0104] PUSCH can be used to send HARQ-ACK and / or CSI together with uplink data (UL-SCH: Uplink Shared CHannel) or uplink data from the MAC layer. In addition, it can also be used to send only CSI or only HARQ-ACK and CSI. That is, it can also be used to send only UCI. In addition, PDSCH or PUSCH can be used to send RRC signaling (also called RRC message) and MAC control elements. Here, in PDSCH, the RRC signaling sent from the base station device can be signaling shared by multiple terminal devices in the cell. In addition, the RRC signaling sent from the base station device can also be signaling dedicated to a certain terminal device (also called dedicated signaling). That is, dedicated signaling can be used to send terminal device-specific (UE-specific) information to a certain terminal device. In addition, PUSCH can be used to send UE capabilities (UE Capability) in the uplink.

[0105] PRACH can be used to send random access preambles. PRACH can be used to indicate the initial connection establishment procedure, the handover procedure, the connection re-establishment procedure, synchronization (timing adjustment) for uplink transmission, and requests for PUSCH (UL-SCH) resources.

[0106] MAC302 is a medium access control layer that maps multiple logical channels to multiple transmission channels. MAC302 can be connected to the upper RLC (Radio Link Control layer) 304 described later through logical channels. Logical channels can be roughly classified according to the type of information transmitted, into control channels for transmitting control information and service channels for transmitting user information. MAC302 can have the function of controlling PHY300 for intermittent transmission and reception (DRX / DTX), the function of executing the random access process, the function of notifying the transmission power information, and the function of performing HARQ control, etc. (Non-patent document 13).

[0107] RLC304 is a radio link control layer that segments the data received from the upper PDCP (Packet Data Convergence Protocol Layer) 206 described later and adjusts the data size so that the lower layer can properly send data. In addition, RLC304 can also have a function for guaranteeing the QoS (Quality of Service) requested by each data. That is, RLC304 can have functions such as data retransmission control (Non-Patent Document 12).

[0108] PDCP306 is a packet data convergence protocol layer that efficiently transmits IP packets (IP packets) as user data in wireless intervals. PDCP306 can have a header compression function that compresses unnecessary control information. In addition, PDCP306 can also have data encryption and data integrity protection functions (Non-Patent Document 11).

[0109] SDAP (Service Data Adaptation Protocol) 310 is a service data adaptation protocol layer (Service Data Adaptation Protocol layer) with the following functions: establishing the correspondence (mapping) between the downlink QoS flow sent from the 5GC110 via the base station device and the DRB, and mapping the uplink QoS flow sent from the terminal device via the base station device to the 5GC110 and the DRB, and storing the mapping rule information (non-patent document 16).

[0110] It should be noted that the data processed in MAC302, RLC304, PDCP306, and SDAP310 are respectively referred to as MAC PDU (Protocol Data Unit), RLC PDU, PDCP PDU, and SDAP PDU. In addition, the data transferred from the upper layer to MAC302, RLC304, PDCP306, and SDAP310 or the data transferred to the upper layer are respectively referred to as MAC SDU (Service Data Unit: Service Data Unit), RLC SDU, PDCP SDU, and SDAP SDU.

[0111] In addition, in order to distinguish between data and control, SDAP PDU can also be referred to as SDAP DATA PDU and SDAP CONTROL PDU, respectively. In addition, in order to distinguish between data and control, PDCP PDU can also be referred to as PDCP DATA PDU and PDCP CONTROL PDU, respectively. In addition, in order to distinguish between data and control, RLC PDU can also be referred to as RLC DATA PDU and RLCCONTROL PDU, respectively.

[0112] Figure 3 (B) is a protocol stack diagram of the CP used when UE122 communicates with gNB108 and AMF (Access and Mobility Management function), which is a logical node that provides functions such as authentication and mobility management in NR106.

[0113] In the protocol stack of CP, in addition to PHY300, MAC302, RLC304, and PDCP306, there are also RRC (Radio Resource Control layer) 308 and NAS (non Access Strarum) 312. RRC308 is a radio link control layer (Radio Link Control layer) that performs processes such as establishment, re-establishment, suspension, and resumption of RRC connections, and re-setting of RRC connections, such as the establishment, change, and release of radio bearers (Radio Bearer: RB) and cell groups (Cell Group), and controls logical channels, transport channels, and physical channels, as well as settings for switching and measurement (Measurement). RB can be divided into signaling radio bearers (Signaling Radio Bearer: SRB) and data radio bearers (Data Radio Bearer: DRB). SRB can be used as a path for sending RRC messages as control information. DRB can be used as a path for sending user data. The setting of each RB can be performed between the RRC308 of gNB108 and UE122. In addition, the part of the RB composed of RLC304 and MAC302 can also be called RLC bearer (non-patent document 10). In addition, with respect to the NAS layer that transports signals between AMF and UE122, part or all of the layers of PHY300, MAC302, RLC304, PDCP306, RRC308, and SDAP310 that transport signals and data between UE122 and gNB108 can be called AS (Access Strarum) layer.

[0114] In addition, SRBs may be defined as SRB0 to SRB3 as follows. SRB0 may be an SRB for RRC messages using CCCH (Common Control Channel) of a logical channel. SRB1 may be an SRB used for (possibly including piggybacked NAS messages) RRC messages and for NAS messages before the establishment of SRB2, or it may use the DCCH (Dedicated Control CHannel) of the logical channel in its entirety. SRB2 may be an SRB used for NAS messages, or it may use the DCCH of the logical channel in its entirety. In addition, SRB2 may have a lower priority than SRB1. SRB3 may be an SRB for specific RRC messages when UE122 is configured with EN-DC, NGEN-DC, NR-DC, etc., or it may use the DCCH of the logical channel in its entirety. In addition, other SRBs may be prepared for other purposes.

[0115] The functional classification of MAC302, RLC304, PDCP306, SDAP310 and RRC308 described above is an example, and part or all of each function may not be implemented. In addition, part or all of the functions of each layer may also be included in other layers.

[0116] It should be noted that the IP layer and the TCP (Transmission Control Protocol) layer, UDP (User Datagram Protocol) layer, and application layer that are higher than the IP layer are any or all of the upper layers of the SDAP layer and the PDCP layer (not shown). In addition, the RRC layer and the NAS (non Access Strarum) layer can also be any or all of the upper layers of the SDAP layer and the PDCP layer (not shown). In other words, any or all of the SDAP layer and the PDCP layer are lower layers of the RRC layer, the NAS layer, the IP layer, and any or all of the TCP (Transmission Control Protocol) layer, UDP (User Datagram Protocol) layer, and application layer that are higher than the IP layer.

[0117] It should be noted that in each embodiment of the present invention, any or all of the SIP (Session Initiation Protocol), SDP (Session Description Protocol), etc. used in IMS, as well as RTP (Real-time Transport Protocol), RTCP (Real-time Transport Control Protocol), HTTP (HyperText Transfer Protocol), etc. used for media communication or media communication control, and codecs for various media, etc., belong to the application layer.

[0118] It should be noted that any one or all of the physical layer, MAC layer, RLC layer, PDCP layer and SDAP layer of the terminal device can be established, set and controlled through the RRC layer of the terminal device. In addition, the RRC layer of the terminal device can establish and / or set the physical layer, MAC layer, RLC layer, PDCP layer and SDAP layer according to the RRC message sent from the RRC layer of the base station device. In addition, the MAC layer (MAC layer), RLC layer (RLC layer), PDCP layer (PDCP layer), and SDAP layer (SDAP layer) can also be referred to as the MAC sublayer (MAC sublayer), RLC sublayer (RLC sublayer), PDCP sublayer (PDCP sublayer), and SDAP sublayer (SDAP sublayer), respectively.

[0119] It should be noted that the layers or functions of the layers belonging to the AS layer set in any one or all of the terminal device and the base station device may also be referred to as entities. That is, any one or all of the physical layer (PHY layer), MAC layer, RLC layer, PDCP layer, SDAP layer and RRC layer or functions of each layer established, set and controlled in any one or all of the terminal device and the base station device may also be referred to as physical entities (PHY entities), MAC entities, RLC entities, PDCP entities, SDAP entities and RRC entities. In addition, each layer may include one or more entities of each layer. In addition, the PDCP entity and the RLC entity may be established, set and controlled for each radio bearer or all. In addition, the MAC entity may be established, set and controlled for each cell group or all. In addition, the SDAP entity may be established, set and controlled for each PDU session or all.

[0120] It should be noted that the COUNT value may be used when performing encryption or integrity protection in the PDCP layer or PDCP entity. The COUNT value may be composed of the HFN (Hyper Frame Number) and the sequence number (SN) attached to the header of the PDCP PDU. The sequence number may be incremented by 1 each time a PDCP DATA PDU is generated in the PDCP layer or PDCP entity on the transmitting side. The HFN may be incremented by 1 each time the sequence number reaches the maximum value.

[0121] It should be noted that, in each embodiment of the present invention, in order to distinguish the protocol of E-UTRA from the protocol of NR, MAC202, RLC204, PDCP206 and RRC208 are also referred to as MAC for E-UTRA or MAC for LTE, RLC for E-UTRA or RLC for LTE, PDCP for E-UTRA or PDCP for LTE, and RRC for E-UTRA or RRC for LTE, respectively. In addition, MAC302, RLC304, PDCP306, and RRC308 are also referred to as MAC for NR, RLC for NR, RLC for NR, and RRC for NR, respectively. Alternatively, spaces are sometimes used to describe E-UTRA PDCP or LTE PDCP, NR PDCP, etc.

[0122] In addition, if Figure 1 As shown, eNB 102, gNB 108, EPC 104, and 5GC 110 can be connected via interface 112, interface 116, interface 118, interface 120, and interface 114. Therefore, in order to correspond to various communication systems, Figure 2 The RRC208 can be replaced by Figure 3 RRC308. In addition, Figure 2 The PDCP 206 can also be replaced by Figure 3 PDCP 306. In addition, Figure 3 The RRC308 may include Figure 2 The function of RRC208. In addition, Figure 3 The PDCP 306 can be Figure 2 PDCP 206. In addition, in E-UTRA 100, even when UE 122 communicates with eNB 102, NR PDCP can be used as PDCP.

[0123] Next, the state transition of UE122 in LTE and NR is described. UE122 connected to EPC can be in RRC_CONNECTED state when RRC connection has been established. In addition, UE122 can be in RRC_INACTIVE state when RRC connection is terminated (if UE122 is connected to 5GC). If these are not the cases, UE122 can be in RRC_IDLE state.

[0124] It should be noted that UE122 connected to the EPC does not have an RRC_INACTIVE state, but can initiate the termination of the RRC connection through E-UTRAN. In this case, when the RRC connection is terminated, UE122 maintains the UE's AS context and the identifier for resumption (resumeIdentity) and transitions to the RRC_IDLE state. When UE122 maintains the UE's AS context, and the resumption of the RRC connection is permitted (Permit) by E-UTRAN, and UE122 needs to transition from the RRC_IDLE state to the RRC_CONNECTED state, the resumption of the terminated RRC connection can be initiated by the upper layer (e.g., NAS layer).

[0125] That is, the definition of suspension may be different in UE122 connected to EPC and UE122 connected to 5GC. In addition, in the case where UE122 is connected to EPC (suspended in RRC_IDLE state) and connected to 5GC (suspended in RRC_INACTIVE state), all or part of the process of recovering from suspension may be different.

[0126] It should be noted that the RRC_CONNECTED state, RRC_INACTIVE state, and RRC_IDLE state may be referred to as a connected mode, an inactive mode, and an idle mode, respectively.

[0127] The AS context of the UE maintained by UE122 may include all or part of the current RRC settings, the current security context, the PDCP state including the ROHC (RObust Header Compression) state, the C-RNTI (Cell Radio Network Temporary Identifier) ​​used in the PCell of the connection source (Source), the cell identifier (cellIdentity), and the physical cell identifier of the PCell of the connection source. It should be noted that the AS context of the UE maintained by any or all of eNB102 and gNB108 may include the same information as the AS context of the UE maintained by UE122, and may also include information different from the information included in the AS context of the UE maintained by UE122.

[0128] The security context may refer to all or part of the information including the encryption key at the AS level, NH (Next Hop parameter), NCC (Next Hop Chaining Counter parameter) for deriving the access key of the next hop, the identifier of the selected AS level encryption algorithm, and the counter used for playback protection.

[0129] Figure 4 This is a diagram showing an example of the flow of procedures for various settings in RRC208 and / or RRC308 according to each embodiment of the present invention. Figure 4 This is an example of a process in which an RRC message is sent from a base station device (eNB102 and / or gNB108) to a terminal device (UE122).

[0130] exist Figure 4 In step S400, the base station device generates an RRC message. The generation of the RRC message in the base station device can be performed when the base station device distributes broadcast information (SI: System Information) and paging information, or when it is determined that the base station device needs to process a specific terminal device, such as security-related settings, re-setting of the RRC connection (processing of wireless line bearers (establishment, change, release, etc.), processing of cell groups (establishment, addition, change, release, etc.), measurement settings, switching settings, etc.), release of the RRC connection state, etc. In addition, the RRC message can be used for switching commands to different RATs. The RRC message includes information (parameters) for various information notifications and settings. In the specifications related to RRC, such as non-patent document 4 or non-patent document 10, these parameters may also be referred to as fields and / or information elements, and are described using the description method of ASN.1 (Abstract Syntax Notation One).

[0131] exist Figure 4 Then, the base station device transmits the generated RRC message to the terminal device (step S402). Then, the terminal device performs processing such as setting according to the received RRC message if processing is required (step S404).

[0132] It should be noted that the generation of RRC messages is not limited to the above examples, and can also be generated for other purposes as described in non-patent document 4, non-patent document 10, etc.

[0133] For example, the RRC message can be used for settings related to dual connectivity (Dual Connectivity: DC) and multi-radio dual connectivity (Multi-Radio Dual Connectivity: MR-DC) described in non-patent document 8.

[0134] Dual Connectivity (DC) may be a technology that uses the radio resources of both the cell groups composed of two base station devices (nodes), namely the master cell group (MCG) composed of the master node (MN) and the secondary cell group (SCG) composed of the secondary node (SN) to perform data communication. In addition, the master node and the secondary node may be the same node (the same base station device). In addition, the MR-DC described in non-patent document 8 may be a technology that groups the cells of the RAT (Radio Access Technology) of both E-UTRA and NR into cells for each RAT and allocates them to the UE, and uses the radio resources of both the MCG and the SCG to perform data communication. In MR-DC, the master node may be a base station having the main RRC functions of MR-DC, such as the addition of secondary nodes, the establishment, change and release of RBs, the addition, change, release, switching of MCGs, etc., and the secondary node may be a base station having some RRC functions, such as the change and release of SCGs.

[0135] In the MR-DC described in non-patent document 8, the RRC of the RAT on the master node side can be used to set up both the MCG and SCG. For example, in the EN-DC (E-UTRA-NR Dual Connectivity: E-UTRA-NR dual connectivity) of the MR-DC where the core network is EPC104 and the master node is eNB102 (also called extended eNB102), and in the NGEN-DC (NG-RAN E-UTRA-NR Dual Connectivity: NG-RAN E-UTRA-NR dual connectivity) of the MR-DC where the core network is 5GC110 and the master node is eNB102, the RRC message of E-UTRA described in non-patent document 4 can be sent and received between eNB102 and UE122. In this case, the RRC message can include not only the setting information of LTE (E-UTRA), but also the setting information of NR described in non-patent document 10. In addition, the RRC message sent from eNB102 to UE122 can also be sent from eNB102 to UE122 via gNB108. In addition, the structure of this RRC message can also be used for non-MR-DC, that is, E-UTRA / 5GC (option 5 described in non-patent document 17) where eNB102 (extended eNB) uses 5GC as the core network.

[0136] Furthermore, on the contrary, in MR-DC described in non-patent document 8, in NE-DC (NR-E-UTRA Dual Connectivity) of MR-DC in which the core network is 5GC110 and the master node is gNB108, the RRC message of NR described in non-patent document 10 can be sent and received between gNB108 and UE122. In this case, the RRC message can include not only the setting information of NR, but also the setting information of LTE (E-UTRA) described in non-patent document 4. In addition, the RRC message sent from gNB108 to UE122 can also be sent from gNB108 to UE122 via eNB102.

[0137] It should be noted that, not limited to the case of using MR-DC, the RRC message for E-UTRA sent from eNB102 to UE122 may include the RRC message for NR, and the RRC message for NR sent from gNB108 to UE122 may include the RRC message for E-UTRA.

[0138] In addition, the network configuration in which the master node is eNB102 and EPC104 is used as the core network may be referred to as E-UTRA / EPC. In addition, the network configuration in which the master node is eNB102 and 5GC110 is used as the core network may be referred to as E-UTRA / 5GC. In addition, the network configuration in which the master node is gNB108 and 5GC110 is used as the core network may be referred to as NR or NR / 5GC. In addition, this name may not be limited to the case where DC is set. When DC is not set, the above-mentioned master node may refer to a base station device that communicates with a terminal device.

[0139] Fig.14 It means in Figure 4 An example of an ASN.1 description of any or all of the fields and information elements related to radio bearer setup included in a message related to re-configuration of an RRC connection in NR. In addition, Fig.15 It means in Figure 4 An example of an ASN.1 description of any or all of the fields and information elements related to radio bearer setup included in a message related to resetting an RRC connection in E-UTRA. In the ASN.1 example, <Omitted> and <Omitted> indicate that other information is omitted, rather than omitting a part of the ASN.1 description. It should be noted that information elements may be omitted where there is no such description as <Omitted> or <Omitted>. It should be noted that the ASN.1 example does not correctly follow the ASN.1 description method, but rather describes an example of parameters of a message related to resetting an RRC connection in an embodiment of the present invention, and other names and other descriptions may also be used. In addition, in order to avoid complicating the description, the ASN.1 example only shows an example of main information closely related to a scheme of the present invention. It should be noted that sometimes parameters described in ASN.1 are not distinguished from fields, information elements, etc., but are all referred to as information elements. In addition, in an embodiment of the present invention, parameters such as fields and information elements described in ASN.1 included in an RRC message are sometimes referred to as information. It should be noted that the message related to the re-setting of the RRC connection can be the RRC re-setting message in NR or the RRC connection re-setting message in E-UTRA.

[0140] exist Fig.14In the information element represented by RadioBearerConfig, the information element represented by RadioBearerConfig is an information element related to the setting of radio bearers such as SRB and DRB, including the PDCP setting information element and SDAP setting information element described later. The information element represented by SRB-ToAddMod included in the information element represented by RadioBearerConfig may be information indicating the setting of SRB (signaling radio bearer), which is sometimes renamed as SRB setting information element or signaling radio bearer setting information element. In addition, the information element represented by SRB-ToAddModList may be a list of information indicating SRB setting. The information element represented by DRB-ToAddMod included in the information element represented by RadioBearerConfig may be information indicating the setting of DRB (data radio bearer), which is sometimes renamed as DRB setting information element or data radio bearer setting information element. The information element represented by DRB-ToAddModList may be a list of information indicating DRB setting. It should be noted that sometimes any one or all of SRB setting and DRB setting are renamed as radio bearer setting.

[0141] The information element represented by SRB-Identity in the SRB configuration information element is the information of the SRB identifier (SRB Identity) of the SRB to be added or changed, or it can be an identifier that uniquely identifies the SRB in each terminal device. It is sometimes also called the SRB identifier information element, the radio bearer identifier information element, or the signaling radio bearer identifier information element.

[0142] The information element represented by DRB-Identity in the DRB configuration information element is the DRB identifier (DRB Identity) information of the DRB to be added or changed, or it can be an identifier that uniquely identifies the DRB in each terminal device. Sometimes it is also called DRB identifier information element or radio bearer identifier information element or data radio bearer identifier information element. The value of DRB identifier is Fig.14 In the example of , it is set to an integer value of 1 to 32, but it can also take other values. In the case of DC, the DRB identifier is unique within the scope of UE122.

[0143] The information element represented by cnAssociation in the DRB setting information element may be an information element indicating whether EPC104 or 5GC110 is used in the core network, and is sometimes also referred to as a core network association establishment information element. That is, when UE122 is connected to EPC, DRB may be associated with the EPS bearer identifier information element (eps-BearerIdentity) in cnAssociation or the EPS bearer identifier (EPS beareridentity) as the value of the EPS bearer identifier information element, and when UE122 is connected to 5GC110, DRB may be associated with the SDAP entity set according to the SDAP setting information element (sdap-Config) described later, or the PDU session information element described later included in the SDAP setting information element, or the PDU session identifier as the value of the PDU session information element, or the PDU session indicated by the PDU session information element. That is, the information represented by cnAssociation may include an EPS bearer identifier information element (eps-BearerIdentity) when EPC104 is used in the core network when EN-DC is used, and include an information element (sdap-Config) representing the SDAP setting when the core network 5GC110 is used, that is, when EN-DC is not used.

[0144] When the core network is 5GC110, the information element represented by sdap-Config may be information related to the setting or resetting of the SDAP entity for determining the correspondence (map) method between the QoS flow and the DRB, and is sometimes also referred to as the SDAP setting information element.

[0145] The field or information element represented by pdu-session or PDU-SessionID included in the SDAP setting information element may be a PDU session identifier of a PDU session described in non-patent document 2 to which a QoS flow corresponding to a radio bearer establishment (map) corresponding to the value of the radio bearer identifier information element included in the DRB setting information element including this SDAP setting information element belongs, and is sometimes also referred to as a PDU session identifier information element. The value of the PDU session identifier information element may be a non-negative integer. In addition, in each terminal device, one PDU session identifier may correspond to multiple DRB identifiers.

[0146] The information element represented by mappedQoS-FlowsToAdd included in the SDAP setting information element may be information including a list of QoS flow identifiers (QFI: QoS Flow Identity) information elements corresponding to (mapped) or additionally corresponding to (mapped) the radio bearer corresponding to the value of the radio bearer identifier information element included in the DRB setting information element of this SDAP setting information element, and is sometimes also referred to as an additional QoS flow information element. The above-mentioned QoS flow may be a QoS flow of a PDU session indicated by the PDU session information element included in this SDAP setting information element.

[0147] In addition, the information element represented by mappedQoS-FlowsToRelease included in the SDAP setting information element may be information including a list of QoS flow identifiers (QFI: QoS Flow Identity) information elements described later, which represent QoS flows corresponding to the radio bearer corresponding to the value of the radio bearer identifier information element (map) included in the DRB setting information element of this SDAP setting information element, and is sometimes also referred to as a released QoS flow information element. The above-mentioned QoS flow may be a QoS flow of a PDU session indicated by the PDU session information element included in this SDAP setting information element.

[0148] The information element represented by QFI may be a QoS flow identifier that uniquely identifies a QoS flow as described in non-patent document 2, sometimes also referred to as a QoS flow identifier information element. The value of the QoS flow identifier information element may be a non-negative integer. In addition, the value of the QoS flow identifier information element may be unique to a PDU session.

[0149] In addition, the SDAP setting information element may include, among other things, an uplink header information element indicating whether an uplink SDAP header exists in the uplink data sent via the set DRB, a downlink header information element indicating whether an downlink SDAP header exists in the downlink data received via the set DRB, a default bearer information element indicating whether the set DRB is a default radio bearer (default DRB), and the like.

[0150] In addition, the information elements represented by pdcp-Config or PDCP-Config in the SRB setting information element and the DRB setting information element may be information elements related to the setting of the NR PDCP entity for establishing and changing the PDCP 306 for SRB and / or DRB, and are sometimes also referred to as PDCP setting information elements. The information elements related to the setting of the NR PDCP entity may include an information element indicating the size of the sequence number for the uplink, an information element indicating the size of the sequence number for the downlink, an information element indicating the profile of header compression (RoHC: RObust Header Compression), a re-ordering timer information element, and the like.

[0151] The information element represented by DRB-ToReleaseList included in the information element represented by RadioBearerConfig may include information indicating one or more DRB identifiers to be released.

[0152] exist Fig.15 In the information element represented by RadioResourceConfigDedicated, the information element represented by RadioResourceConfigDedicated may be an information element used for setting, changing, releasing, etc. a radio bearer. The information element represented by SRB-ToAddMod included in the information element represented by RadioResourceConfigDedicated may be information indicating SRB (signaling radio bearer) setting, sometimes also renamed as SRB setting information element or signaling radio bearer setting information element. The information element represented by SRB-ToAddModList may be a list of information indicating SRB setting. The information element represented by DRB-ToAddMod included in the information element represented by RadioResourceConfigDedicated may be information indicating DRB (data radio bearer) setting, sometimes also renamed as DRB setting information element or data radio bearer setting information element. The information element represented by DRB-ToAddModList may be a list of information indicating DRB setting. It should be noted that sometimes any one or all of SRB setting and DRB setting are also renamed as radio bearer setting.

[0153] The information element represented by SRB-Identity in the SRB configuration information element is the information of the SRB identifier (SRB Identity) of the SRB to be added or changed, or it can be an identifier that uniquely identifies the SRB in each terminal device. It is sometimes also called the SRB identifier information element, the radio bearer identifier information element, or the signaling radio bearer identifier information element. Fig.15The information element represented by SRB-Identity can be Fig.14 This information element has the same function as the information element represented by SRB-Identity.

[0154] The information element represented by DRB-Identity in the DRB setting is the DRB identifier (DRB Identity) information of the DRB to be added or changed, or it can be an identifier that uniquely identifies the DRB in each terminal device. Sometimes it is also called DRB identifier information element or radio bearer identifier information element or data radio bearer identifier information element. The value of DRB identifier is Fig.15 In the example, it is set to an integer value from 1 to 32, but other values ​​can also be used. Fig.15 The information element represented by DRB-Identity can be Fig.14 This information element has the same function as the information element represented by DRB-Identity.

[0155] The information element represented by eps-BearerIdentity in the DRB setup information element may be an EPS bearer identifier that uniquely identifies the EPS bearer in each terminal device. The information element represented by eps-BearerIdentity is sometimes also referred to as an EPS bearer identifier information element. The value of the EPS bearer identifier is Fig.15 In the example, it is set to an integer value from 1 to 15, but other values ​​can also be taken. Fig.15 The information element represented by eps-BearerIdentity can be Fig.14 The EPS bearer identifier and the DRB identifier may correspond one-to-one in each terminal device.

[0156] In addition, the information element represented by pdcp-Config or PDCP-Config in the SRB setting information element and the DRB setting information element may be an information element related to the setting of the E-UTRA PDCP entity for establishing and changing the PDCP 206 for SRB and / or for DRB, and is sometimes also referred to as the PDCP setting information element. The information elements related to the setting of the E-UTRA PDCP entity may include an information element indicating the size of the sequence number, an information element indicating the profile of header compression (RoHC: RObust Header Compression), re-ordering timer information, etc.

[0157] also, Fig.14 or Fig.15Some or all of the information elements shown may be optional. Fig.14 or Fig.15 The information elements shown may be included in the message related to the reconfiguration of the RRC connection as needed and conditionally. In addition, in the message related to the reconfiguration of the RRC connection, in addition to the information elements related to the configuration of the radio bearer, an information element indicating that the full configuration is applied may be included. The information element indicating that the full configuration is applied may be represented by an information element name such as fullConfig, or may be represented by true and enable, etc.

[0158] The information element represented by DRB-ToReleaseList included in the information element represented by RadioResourceConfigDedicated may include information indicating one or more DRB identifiers to be released.

[0159] In the following description, eNB102 and / or gNB108 are also referred to only as base station devices, and UE122 is also referred to only as terminal devices.

[0160] When establishing an RRC connection, re-establishing an RRC connection, or switching, a serving cell provides mobility information for NAS. When re-establishing an RRC connection, or switching, a serving cell provides security input. The serving cell is referred to as the primary cell (PCell). In addition, one or more serving cells (secondary cells, SCells) can be added and set together with the primary cell, depending on the capabilities of the terminal device.

[0161] In addition, a set of service cells consisting of two subsets may be set for the terminal device. The two subsets may be composed of: a cell group (primary cell group) consisting of one or more service cells including a primary cell (PCell) and one or more cell groups (secondary cell groups) consisting of one or more service cells including a primary secondary cell (PSCell) but not including the primary cell. The primary and secondary cells may be cells for which PUCCH resources are set.

[0162] An example of an operation related to a radio link failure (RLF: Radio Link Failure) of a terminal device based on an RRC connection is described.

[0163] The terminal device obtains the following information from the base station device in the service area through broadcast information and RRC messages to each user: the value (t310, t313) of the timer (e.g., T310, T313) used to detect physical layer problems (Physical layer problems) of the service cell, N310, N313 as the threshold of the number of detections of out-of-sync (OoS), N311, N314 as the threshold of the number of detections of in-sync (IS), etc. In addition, the value of the timer and the threshold of the number of times can be set to a default value. In addition, the names of the timers can be different in EUTRA and NR.

[0164] In order to monitor the wireless link, the physical layer processing unit of the terminal device, for example, estimates that the wireless link quality of the service cell is worse than a specific threshold value (Qout) for more than a specific period of time (for example, TEvaluate_Qout = 200ms) based on information such as the received power of the reference signal and / or the received power of the synchronization signal and / or the packet error rate, and notifies the RRC layer processing unit as the upper layer that it is "out-of-sync". In addition, the physical layer processing unit, for example, estimates that the wireless link quality of the service cell is worse than a specific threshold value (Qin) for more than a specific period of time (for example, TEvaluate_Qin = 100ms) based on information such as the received power of the reference signal and / or the received power of the synchronization signal and / or the packet error rate, and notifies the RRC layer processing unit as the upper layer that it is "in-sync". It should be noted that the physical layer processing unit can notify the upper layer of out-of-sync or in-sync at a specific interval (for example, TReport_sync = 10ms).

[0165] Here, for example, the threshold Qout can be defined as a level where the radio link of the downlink cannot be reliably received, and the block error rate of the transmission of the hypothetical downlink control channel (PDCCH) based on predetermined parameters is a first specific ratio. In addition, for example, the threshold Qin can also be defined as a level where the radio link quality of the downlink can be significantly and more reliably received than the state of Qout, and the block error rate of the transmission of the hypothetical downlink control channel based on predetermined parameters is a second specific ratio. In addition, multiple block error rates (levels of threshold Qout and threshold Qin) can be defined based on the frequency used, subcarrier spacing, category of service, etc. In addition, the first specific ratio and / or the second specific ratio can be a predetermined value specified in the specification. In addition, the first specific ratio and / or the second specific ratio can also be a value notified or broadcasted to the terminal device by the base station device.

[0166] The terminal device may use a certain type of reference signal (e.g., a cell-specific reference signal (CRS)) to perform radio link monitoring in a serving cell (e.g., PCell and / or PSCell). In addition, the terminal device may receive a setting (radio link monitoring setting: RadioLinkMonitoringConfig) from a base station device indicating which reference signal to use in radio link monitoring in a serving cell (e.g., PCell and / or PSCell), and use the set one or more reference signals (referred to herein as RLM-RS) to perform radio link monitoring. In addition, the terminal device may also use other signals to perform radio link monitoring. The physical layer processing unit of the terminal device may notify an upper layer of synchronization when the conditions for being in synchronization are met in a serving cell (e.g., PCell and / or PSCell).

[0167] The wireless link monitoring setting may include information indicating the purpose of monitoring and identifier information indicating a reference signal. For example, the purpose of monitoring may include the purpose of monitoring the failure of a wireless link, the purpose of monitoring the failure of a beam, or both of these purposes. In addition, for example, the identifier information indicating the reference signal may include information indicating an identifier (SSB-Index) of a synchronization signal block (Synchronization Signal Block: SSB) of a cell. That is, the reference signal may include a synchronization signal. In addition, for example, the identifier information indicating the reference signal may include information indicating an identifier associated with a channel state information reference signal (CSI-RS) set to a terminal device.

[0168] In the main cell, the RRC layer processing unit of the terminal device can start (Start) or restart (Restart) the timer (T310) when receiving the out-of-synchronization notification from the physical layer processing unit for a predetermined number of consecutive times (N310 times). In addition, the RRC layer processing unit of the terminal device can stop (Stop) the timer (T310) when receiving the synchronization for a predetermined number of consecutive times (N311 times). The RRC layer processing unit of the terminal device can implement a transition to an idle state or a re-establishment process of the RRC connection when the timer (T310) expires (Expire). For example, the action of the terminal device may be different depending on the establishment status of AS security (AS Security). When AS security is not established, the terminal device can transition to the RRC IDLE state, and when AS security is established, the terminal device can perform the re-establishment process of the RRC connection. In addition, in the judgment of starting or restarting the timer T310, the condition that the timer T300, timer T301, timer T304 and timer T311 are not running can be added.

[0169] exist Fig. 9 An example of the conditions for starting, stopping and expiring each timer in EUTRA is shown in FIG. It should be noted that the timer name and / or message name may be different in NR, but the same conditions may also be applied.

[0170] In addition, in the primary and secondary cells, the RRC layer processing unit of the terminal device can start (Start) or restart (Restart) the timer (T313) when receiving the out-of-synchronization notification from the physical layer processing unit for a predetermined number of consecutive times (N313 times). In addition, the RRC layer processing unit of the terminal device can stop (Stop) the timer (T313) when receiving the synchronization for a predetermined number of consecutive times (N314 times). The RRC layer processing unit of the terminal device can execute the SCG failure information procedure (SCG failure information procedure) for notifying the network of the SCG failure when the timer (T313) expires (Expire).

[0171] In addition, in the SpCell (PCell in MCG and PSCell in SCG), the RRC layer processing unit of the terminal device can start (Start) or restart (Restart) the timer (T310) of the SpCell when receiving the out-of-synchronization notification from the physical layer processing unit in each SpCell for a predetermined number of consecutive times (N310 times). In addition, the RRC layer processing unit of the terminal device can stop (Stop) the timer (T310) of the SpCell when receiving the synchronization in each SpCell for a predetermined number of consecutive times (N311 times). When the timer (T310) of each SpCell expires (Expire), if the SpCell is a PCell, the RRC layer processing unit of the terminal device can implement a transition to an idle state or a re-establishment process of the RRC connection. In addition, if the SpCell is a PSCell, an SCG failure information procedure (SCGfailure information procedure) for notifying the network of an SCG failure can be executed.

[0172] The above description is an example when intermittent reception (DRX) is not set for the terminal device. When DRX is set for the terminal device, the RRC layer processing unit of the terminal device can set the time period for measuring the quality of the wireless link and the notification interval to the upper layer for the physical layer processing unit so that it takes a different value from the case where DRX is not set. It should be noted that even when DRX is set, when the above-mentioned timers (T310, T313) are running, the time period for measuring the quality of the wireless link used to estimate synchronization and the notification interval to the upper layer can be set to the values ​​when DRX is not set.

[0173] In addition, for example, in order to detect an early physical layer problem, the RRC layer processing unit of the terminal device may start (Start) a timer (T314) when receiving an early out-of-sync notification from the physical layer processing unit for a predetermined number of times (N310 times). In addition, the RRC layer processing unit of the terminal device may stop (Stop) a timer (T314) when receiving synchronization for a predetermined number of times (N311 times) while T314 is running.

[0174] In addition, for example, in order to detect an early physical layer improvement, the RRC layer processing unit of the terminal device may start (Start) a timer (T315) when receiving early synchronization notified from the physical layer processing unit for a predetermined number of times (N311 times) in succession. In addition, the RRC layer processing unit of the terminal device may stop (Stop) a timer (T315) when receiving synchronization for a predetermined number of times (N311 times) in succession while T315 is running.

[0175] In addition, for example, when reporting the measurement to the base station device, when the measurement setting is set to perform a first measurement (for example, a measurement using timer T312), if timer T310 is running and timer T312 is not running, timer T312 is started. The RRC layer processing unit of the terminal device can stop the timer (T312) when synchronization is received for a predetermined number of consecutive times (N311 times).

[0176] In addition, if the network does not explicitly or implicitly set the RLM-RS, the RLM-RS may be undefined. That is, if the network (eg, the base station device) does not set the RLM-RS, the terminal device may not perform radio link monitoring.

[0177] In addition, RLM-RS is a reference signal used for radio link monitoring, and a plurality of RLM-RS can be set for a terminal device. A resource of one RLM-RS can be a resource (or port) of one SS block or one CSI-RS.

[0178] In addition, wireless link monitoring using CRS can be performed in EUTRA cells, and wireless link monitoring using RLM-RS can be performed in NR cells, but the present invention is not limited to this.

[0179] The detection of radio link failure based on radio link monitoring will be described.

[0180] When the terminal device is notified of a random access problem from the MAC layer of the MCG when timer T310 expires (Expire), when timer T312 expires, when multiple specific timers are not running, or when the terminal device is notified from the RLC layer of the MCG that the retransmission of SRB or DRB has reached the maximum number of retransmissions, it is determined that the terminal device has detected a radio link failure in the MCG. The specific timers do not include timer T310 and timer T312.

[0181] It may be that, in the MAC entity, when the number of retransmissions of the random access preamble reaches a predetermined number, if the random access preamble is sent in the SpCell, the MAC entity of the cell group including the SpCell notifies the upper layer (here, the RRC entity) of the random access problem.

[0182] When the terminal device determines that a radio link failure is detected in the MCG, it stores various information as radio link failure information. Then, if the AS security is not activated, the release reason is set to "other" to start the process of leaving RRC_CONNECTED. If the AS security is activated, the process of reestablishing the RRC connection begins.

[0183] When timer T313 expires (Expire), when the terminal device is notified of a random access problem from the MAC layer of the SCG, or when the terminal device is notified from the RLC layer of the SCG that the maximum number of retransmissions has been reached, it is determined that the terminal device has detected a wireless link failure in the SCG and begins processing for reporting information associated with the SCG wireless link failure to the base station device.

[0184] When the timer T314 expires (Expire), the terminal device determines that the terminal device has detected an "early out-of-sync" event, and starts processing for reporting related information to the base station device.

[0185] When the timer T315 expires (Expire), the terminal device determines that the terminal device has detected an "early synchronization" event, and starts processing for reporting related information to the base station device.

[0186] The process of re-establishing the RRC connection is described.

[0187] The purpose of the RRC connection re-establishment process is to re-establish the RRC connection, which may be accompanied by the SRB1 resumption process, secure reactivation, and PCell-only settings.

[0188] The RRC connection re-establishment process may be initiated when any of the following conditions (A) to (E) are met.

[0189] (A) When the MCG wireless link fails

[0190] (B) When the switching fails (when the synchronization resetting in MCG fails in NR)

[0191] (C) When migration to another RAT fails

[0192] (D) When the lower layer is notified of the failure of the integrity check related to SRB1 or SRB2

[0193] (E) When resetting the RRC connection fails

[0194] When the RRC connection re-establishment process starts, the terminal device performs part or all of the following processes (A) to (J).

[0195] (A) If timer T310 is running, stop timer T310

[0196] (B) If timer T312 is running, stop timer T312

[0197] (C) If timer T313 is running, stop timer T313

[0198] (C) If timer T314 is running, stop timer T314

[0199] (D) Start timer T311

[0200] (E) Suspend all RBs except SRB0

[0201] (F) Reset MAC

[0202] (G) If set, release the SCell of MCG

[0203] (H) Apply the default physical channel settings

[0204] (I) Apply default MAC master settings to MCG

[0205] (J) Execute cell selection process

[0206] When selecting the optimal cell of the same RAT through the cell selection process, the terminal device performs the following processing.

[0207] If the terminal device is connected to 5GC and the selected cell can only be connected in EPC, or the terminal device is connected to EPC and the selected cell can only be connected in 5GC, the release reason is set to "RRC connection failure" and the action of leaving RRC_CONNECTED is executed. Otherwise, stop timer T311, start timer T301, and start sending the RRC connection reestablishment request message.

[0208] When timer T311 expires, the terminal device sets the release reason to "RRC connection failure" and executes the action of leaving RRC_CONNECTED.

[0209] If the timer T301 expires or the selected cell is no longer the optimal cell from the perspective of the cell selection criteria, the terminal device sets the release reason to "RRC connection failure" and executes an action to leave RRC_CONNECTED.

[0210] The switching is explained.

[0211] use Figure 7 , an example of processing related to handover between the same RATs (i.e., between EUTRA) in EUTRA is described. Figure 7 The description is an example, and a part of the processing may be omitted, or other processing may be included. Alternatively, other processing may be performed as processing related to the switching.

[0212] exist Figure 7 In the switching process, the base station device (source eNB) of the switching source configures (Configures) the measurement of the neighboring cell for the terminal device (step S701).

[0213] The terminal device performs the measurement set by the source eNB, and reports the measurement result to the source eNB based on the reporting condition (step S702).

[0214] The source eNB decides on the handover of the terminal device based on the reported measurement results and other information (step S703).

[0215] The source eNB issues a handover request message including information required for preparing a handover to a base station apparatus (Target eNB) that is a handover destination (step S704).

[0216] Admission control can be performed in the target eNB. The target eNB sets the required resources (step S705).

[0217] The target eNB sends a HANDOVER REQUEST ACKNOWLEDGE message to the source eNB (step S706). The HANDOVER REQUEST ACKNOWLEDGE message includes a container that is transparently sent to the terminal device as an RRC message for the execution of the handover. The container may include a new C-RNTI, a security algorithm identifier of the target eNB for the selected security algorithm, a preamble of a dedicated random access channel (random access preamble), and part or all of the system information of the target cell.

[0218] The source eNB sends the container (the first RRC connection reconfiguration message (RRCConnectionReconfiguration message) including the mobility control information (mobilityControlInfo) information element (Information Element: IE)) received from the target eNB to the terminal device (step S707).

[0219] It should be noted that, when a make-before-break HO (MBB-HO) is configured through the first RRC connection reconfiguration message, after receiving the first RRC connection reconfiguration message, the terminal device maintains the connection with the source eNB at least in the target eNB until the initial uplink transmission is performed. It should be noted that the above-mentioned make-before-break switching can be selected from multiple settings. For example, it can be determined that a make-before-break switching is configured by setting the makeBeforeBreak-r14 of the field included in the standardized mobilityControlInfo information element to true. In addition, for example, it can be determined that a make-before-break switching is configured by setting the newly defined makeBeforeBreak-r16 field included in the mobilityControlInfo information element to true. In addition, the field makeBeforeBreak-r16 can use information elements including various settings as values.

[0220] The source eNB transmits an SN STATUS TRANSFER message for conveying the reception status of the uplink PDCP sequence number and the transmission status of the downlink PDCP sequence number to the target eNB (step S708).

[0221] If RACH-less switching is not set through the first RRC connection reconfiguration message, the terminal device performs (Perform) synchronization to the target eNB and uses the random access channel to access the target cell. At this time, if a dedicated random access preamble is indicated by the first RRC connection reconfiguration message, a contention-free random access procedure is performed. If a dedicated random access preamble is not indicated, a contention-based random access procedure is performed. If RACH-less switching is set through the first RRC connection reconfiguration message, the terminal device performs synchronization to the target eNB (step S709).

[0222] If RACH-less switching is not set through the first RRC connection re-setting message, the target eNB returns information of uplink allocation and timing advance to the terminal device (step S710).

[0223] If RACH-less switching is configured through the first RRC connection reconfiguration message, and the periodic pre-allocated uplink grant cannot be obtained through the first RRC connection reconfiguration message, the terminal device receives the uplink grant through the PDCCH of the target cell. The terminal device uses the first available uplink grant after synchronization to the target cell (step S710a).

[0224] When RACH-less switching is not configured and the terminal device successfully accesses the target cell, the terminal device sends an RRC connection reconfiguration completion message (RRCConnectionReconfigurationComplete message) to the target eNB to confirm the switching. The RRC connection reconfiguration completion message indicates the completion of the switching process of the terminal device. The RRC connection reconfiguration completion message includes C-RNTI, and the target eNB verifies the C-RNTI of the received RRC connection reconfiguration completion message.

[0225] When RACH-less switching is configured and the terminal device receives an uplink authorization, the terminal device sends an RRC Connection Reconfiguration Complete message (RRCConnectionReconfigurationComplete message) to the target eNB to confirm the switching. The RRC Connection Reconfiguration Complete message includes C-RNTI, and the target eNB verifies the C-RNTI of the accepted RRC Connection Reconfiguration Complete message. When the terminal device receives the UE contention resolution identity MAC control element (UE contention resolution identity MAC control element) from the target eNB, the switching process of the terminal device is completed (step S711).

[0226] The target eNB sends a path switch request (PATH SWITCH REQUEST) to the MME to notify the terminal device that the cell has been changed (step S712).

[0227] The MME sends a MODIFY BEARER REQUEST message to the serving gateway (S-GW) (step S713).

[0228] The S-GW switches the downlink data path to the target side. The S-GW sends one or more end marker packets to the source eNB to release the user plane resources to the source eNB (step S714).

[0229] The S-GW sends a MODIFY BEARER RESPONSE message to the MME (step S715 ).

[0230] The MME confirms the path switch request through a PATH SWITCH REQUEST ACKNOWLEDGE message (step S716).

[0231] The target eNB indicates the success of the handover by sending a UE CONTEXT RELEASE message to the source eNB, triggering the release of resources by the source eNB. The target eNB may send this message after receiving the Path Switch Request Acknowledge message (step S717).

[0232] The source eNB can release the radio resources related to the UE context and the C-plane resources when receiving the UE context release message, and can continue the ongoing data transmission (step S718).

[0233] When the timer T304 expires, the terminal device executes part or all of the following processes (A) to (D).

[0234] (A) The dedicated random access channel configuration configured by the first RRC connection reconfiguration message is considered unusable

[0235] (B) Return the terminal device settings to the dedicated physical channel settings and the main settings of the MAC layer and the settings used in the PCell of the switching source (source) except for the settings of the semi-persistent (semi-static) scheduling

[0236] (C) Storing the associated information as handover failure information

[0237] (D) Start the RRC connection re-establishment process and end the RRC connection re-establishment process

[0238] The details of the processing of the terminal device receiving the first RRC connection re-establishment message are described. The first RRC connection re-establishment message may include a mobility control information (mobilityControlInfo) information element. The mobilityControlInfo information element includes parameters related to the mobility associated with the EUTRA or the network control within the EUTRA from other RATs (for example, the identifier of the target cell, the carrier frequency information).

[0239] If an RRC connection reconfiguration message (first RRC connection reconfiguration message) including the mobilityControlInfo information element is received and the terminal device can meet the settings of the message, the terminal device performs part or all of the following processes (A) to (G).

[0240] (A) If timer T310 is running, stop timer T310

[0241] (B) If timer T312 is running, stop timer T312

[0242] (C) If timer T314 is running, stop timer T314

[0243] (D) Start timer T304 with the value (t304) included in the mobilityControlInfo information element

[0244] (E) If the carrier frequency information is included, the frequency is determined as the frequency of the target cell; if the carrier frequency information is not included, the frequency of the source PCell is determined as the frequency of the target cell.

[0245] (F) If the access restriction timer is running, stop the timer

[0246] (G) Start synchronization of the target cell to the downlink

[0247] use Figure 8 , an example of processing related to handover between the same RAT (i.e., between NRs) in NR is described. Figure 8 The description is an example, and a part of the processing may be omitted, or other processing may be included. Alternatively, other processing may be performed as processing related to the switching.

[0248] exist Figure 8 In the process, the base station device of the switching source (Source gNB) sets the measurement of the adjacent cell for the terminal device, and the terminal device performs the measurement set by the source gNB and reports the measurement result to the source gNB (step S801).

[0249] The source gNB decides to switch the terminal device based on information such as the reported measurement results (step S802).

[0250] The source gNB issues a handover request message including the information required to prepare for handover to the base station device (Target gNB) serving as the handover destination (step S803).

[0251] Admission control can be performed in the target gNB (step S804).

[0252] The target gNB prepares for handover and sends a HANDOVER REQUESTACKNOWLEDGE message to the source gNB (step S805). The HANDOVER REQUESTACKNOWLEDGE message includes a container that is transparently sent to the terminal device as an RRC message for executing the handover.

[0253] The source gNB sends the container (first RRC reconfiguration message (RRCReconfiguration message)) received from the target gNB to the terminal device (step S806). The RRC reconfiguration message may include the identifier of the target cell, the new C-RNTI, the security algorithm identifier of the target gNB for the selected security algorithm, the set of dedicated random access channel resources, the UE-specific CSI-RS settings, the common random access channel resources, and part or all of the system information of the target cell.

[0254] It should be noted that, when Make-Before-Break HO (MBB-HO) is configured through the first RRC reconfiguration message, the terminal device can, after receiving the first RRC reconfiguration message, maintain the connection with the source gNB in ​​at least the target gNB until the initial uplink transmission is performed.

[0255] The source eNB sends an SN status transition message to the target gNB to convey (Convey) the reception status of the sequence number of the uplink PDCP and the transmission status of the sequence number of the downlink PDCP (step S807).

[0256] If the RACH-less switch is not set through the first RRC reset message, the terminal device performs synchronization to the target eNB and uses the random access channel to access the target cell. At this time, if a dedicated random access preamble is indicated by the first RRC reset message, a contention-free random access process is performed, and if a dedicated random access preamble is not indicated, a contention-based random access process is performed. If the RACH-less switch is set through the first RRC reset message, the terminal device performs synchronization to the target gNB.

[0257] If the RACH-less handover is not configured via the first RRC reconfiguration message, the target gNB may return information of the uplink allocation and timing advance to the terminal device.

[0258] If RACH-less switching is configured via the first RRC reconfiguration message and the periodic pre-allocated uplink grant cannot be obtained via the first RRC reconfiguration message, the terminal device receives the uplink grant via the PDCCH of the target cell. The terminal device uses the first available uplink grant after synchronization to the target cell.

[0259] When RACH-less switching is not configured and the terminal device successfully accesses the target cell, the terminal device can send an RRC reconfiguration completion message (RRCReconfigurationComplete message) to the target gNB to confirm the switching. The RRC reconfiguration completion message can indicate the completion of the switching process of the terminal device. The RRC reconfiguration completion message includes C-RNTI, and the target gNB can verify the C-RNTI of the received RRC reconfiguration completion message.

[0260] When a RACH-less handover is configured and the terminal device receives an uplink grant, the terminal device may send an RRCReconfigurationComplete message to the target gNB to confirm the handover. The RRCReconfigurationComplete message includes the C-RNTI, and the target gNB may verify the C-RNTI of the received RRCReconfigurationComplete message. The handover process of the terminal device may be completed when the terminal device receives a UE contention resolution identity MAC control element from the target gNB (step S808).

[0261] The target eNB sends a path switch request (PATH SWITCH REQUEST) message to the AMF to switch the downlink data path of the 5GC to the target gNB, so that the target gNB establishes an NG-C interface instance (step S809).

[0262] 5GC switches the downlink data path to the target gNB. UPF (User Plane Function) sends one or more end marker packets to the source eNB to release the user plane resources to the source gNB (step S810).

[0263] The AMF confirms the path switch request through a PATH SWITCH REQUEST ACKNOWLEDGE message (step S811).

[0264] The target gNB indicates the success of the handover by sending a UE CONTEXT RELEASE message to the source eNB, triggering the release of resources by the source gNB. The target gNB may send this message after receiving the PATH SWITCH REQUEST ACKNOWLEDGE message from the AMF. The source gNB may release the radio and C-plane associated resources related to the UE context upon receiving the UE CONTEXT RELEASE message. The ongoing data transmission may continue (step S812).

[0265] When the timer T304 expires, the terminal device executes part or all of the following processes (A) to (D).

[0266] (A) If the timer T304 of the MCG expires, the setting of the dedicated random access channel of the MCG set by the first RRC connection resetting message is released.

[0267] (B) If the timer T304 of the MCG expires, the terminal device settings are returned to the settings used in the PCell of the switching source (source)

[0268] (D) If the MCG timer T304 expires, the RRC connection re-establishment process begins

[0269] (E) If the SCG timer T304 expires, the setting of the SCG dedicated random access channel set by the first RRC connection resetting message is released.

[0270] (E) If the SCG timer T304 expires, the process of reporting the failure of SCG synchronization resetting begins

[0271] The details of the processing of the terminal device receiving the first RRC reconfiguration message are described. The first RRC reconfiguration message may include a synchronization reconfiguration (reconfigurationWithSync) information element. The reconfigurationWithSync information element may include the settings of the SpCell for each cell group (MCG, SCG) in the RRC reconfiguration message. The reconfigurationWithSync information element includes parameters related to the reconfiguration accompanied by synchronization to the target SpCell (e.g., the settings of the target SpCell, the new identifier of the terminal device, etc.).

[0272] The terminal device that receives the RRC reconfiguration message (first RRC reconfiguration message) including the reconfigurationWithSync information element performs part or all of the following processes (A) to (E).

[0273] (A) If security is not activated, the release reason is set to "other" and the process of leaving RRC_CONNECTED is started. The process of leaving RRC_CONNECTED may be the process of entering RRC_IDLE.

[0274] (B) If the timer T310 of the target SpCell is running, stop the timer T310 of the target SpCell

[0275] (C) Start the timer T304 of the target SpCell with the value (t304) included in the reconfigurationWithSync information element

[0276] (D) If the frequency information of the downlink is included, the frequency is determined as the frequency of the SSB of the target cell. If the frequency information of the downlink is not included, the frequency of the SSB of the source SpCell is determined as the frequency of the SSB of the target cell.

[0277] (E) Start synchronization of the target cell to the downlink

[0278] As described above, in eutra and / or NR, when a make-before-break HO (MBB-HO) is set for the terminal device, the terminal device maintains a connection with the source eNB or source gNB in ​​the target eNB or target gNB until the initial uplink transmission is performed. The current situation is that timer T310 stops when the first RRC connection reconfiguration message or the first RRC reconfiguration message is received. Therefore, in the service cell (source cell) of the source eNB or source gNB from then on, the terminal device cannot determine whether it is a situation where the radio link failure is regarded as caused by a physical layer problem. In addition, when timer T304 is running, in the service cell (source cell) of the source eNB or source gNB, the terminal device cannot determine whether it is a situation where the radio link failure is regarded as caused by a problem with the random access notified from the MAC layer. In addition, in the source cell, when the retransmission in the RLC reaches the maximum number of times, it is regarded as a radio link failure, and the RRC connection re-establishment process is performed.

[0279] Next, conditional handover is explained. In NR, conditional handover may be an RRC reconfiguration using an RRC reconfiguration message, wherein the RRC reconfiguration message includes: an information element (conditional handover setting) including information included in a synchronization reconfiguration information element, and information indicating a condition for applying the information element (conditional handover condition). In LTE, conditional handover may be an RRC connection reconfiguration using an RRC connection reconfiguration message, wherein the RRC connection reconfiguration message includes: an information element (conditional handover setting) including information included in a mobility control information information element, and information indicating a condition for applying the information element (conditional handover condition).

[0280] In NR, the conditional switching settings may include part or all of the following settings (A) to (F).

[0281] (A) Cell Group Configuration Information (CellGroupConfig)

[0282] (B) Information indicating whether the settings are complete

[0283] (C) NAS layer messages

[0284] (D) System Information

[0285] (E) Measurement settings

[0286] (F) Radio Bearer Configuration

[0287] The setting information of the cell group may include part or all of the following settings (1) to (6).

[0288] (1) Cell group identifier

[0289] (2) Information carried by RLC

[0290] (3) MAC layer configuration information of the cell group

[0291] (4) Physical (PHY) layer configuration information of the cell group

[0292] (5) SpCell configuration information (including synchronization reset information element)

[0293] (6) SCell information

[0294] In addition, the radio bearer settings may include part or all of the following settings (1) to (3).

[0295] (1) SRB settings

[0296] (2) DRB settings

[0297] (3) Security settings (e.g., information on the integrity protection algorithm and encryption algorithm for SRB and / or DRB (securityAlgorithmConfig), information indicating which key to use (primary (MCG) or secondary (SCG) key (keyToUse), etc.)

[0298] In LTE, the conditional switching setting may include part or all of the following settings (A) to (E).

[0299] (A) Measurement settings

[0300] (B) Mobility Control Information Element

[0301] (C) NAS layer messages

[0302] (D) Wireless resource settings

[0303] (E) Security settings (e.g., information related to the integrity protection algorithm and encryption algorithm for SRB and / or DRB (SecurityAlgorithmConfig))

[0304] The wireless resource configuration may include part or all of the following configurations (1) to (4).

[0305] (1) SRB information

[0306] (2) DRB information

[0307] (3) MAC layer configuration information of the cell group

[0308] (4) Physical (PHY) layer configuration information of the cell group

[0309] In LTE and / or NR, the conditional switching condition may include part or all of the following conditions (A) to (D).

[0310] (A) The handover destination (target) cell is better than the current (source) PCell to which the offset is applied

[0311] (B) The handover destination (target) cell is better than a certain threshold, and the PCell is worse than the other thresholds

[0312] (C) The cell of the handover destination (target) is better than a certain threshold

[0313] (D) Unconditional (Immediate Execution)

[0314] In the comparison under the above-mentioned conditional switching condition, RSRP, RSRQ and / or RS-SINR can be used as quantity (Quantity). In addition, which quantity to use can be set from the network. In addition, information indicating which quantity to use can be included in the conditional switching condition.

[0315] The information element representing the conditional switching setting and / or the conditional switching condition may be included as part of the RRC message in the switching source (source), or may be stored in a container (information element storing a bit string) included in the RRC message.

[0316] Based on the above description, various embodiments of the present invention will be described. It should be noted that the above-described processes can be applied to the processes omitted in the following description.

[0317] An example is shown in which MBB-HO is efficiently performed by changing a procedure related to radio link monitoring in MBB-HO.

[0318] First, in the main cell (PCell) of the SpCell serving as the MCG, regardless of whether the timer T304 is running under a specific condition (first condition), the RRC layer processing unit of UE122 can start (Start) or restart (Restart) the timer (T310) when receiving the out-of-synchronization notification from the physical layer processing unit for a predetermined number of consecutive times (N310 times). In addition, the RRC layer processing unit of UE122 can stop (Stop) the timer (T310) when receiving the synchronization for a predetermined number of consecutive times (N311 times). In addition, in the judgment of starting or restarting the timer T310, the condition that the timer T300, the timer T301, and the timer T311 are not running can be added.

[0319] The RRC layer processing unit of UE 122 determines that a radio link failure is detected in the MCG when any of the following conditions (A) to (E) are met.

[0320] (A) When timer T310 expires (Expire)

[0321] (B) When timer T312 expires

[0322] (C) When receiving a notification (indication) of a random access problem from the MAC entity of the MCG while the timer T300, timer T301, timer T304, and timer T311 are not running

[0323] (D) Under the first condition, when timer T304 is running and a notification of a random access problem is received from the MAC entity of the MCG

[0324] (E) When receiving a notification from the RLC layer of the MCG indicating that the retransmission of SRB or DRB has reached the maximum number of retransmissions

[0325] The first condition may be that makeBeforeBreak-r16 is set in UE122. Setting makeBeforeBreak-r16 may be, for example, in the case of EUTRA, UE122 receives an RRC connection resetting message in which makeBeforeBreak-r16 is included in the field of the mobilityControlInfo information element. In addition, setting makeBeforeBreak-r16 may be, for example, in the case of NR, receiving an RRC connection resetting message in which makeBeforeBreak-r16 is included in the field of the synchronization resetting information element. In addition, not setting makeBeforeBreak-r16 may be, for example, in the case of EUTRA, UE122 receives an RRC connection resetting message in which makeBeforeBreak-r16 is not included in the field of the mobilityControlInfo information element. In addition, not setting makeBeforeBreak-r16 may be, for example, in the case of EUTRA, UE122 receives an RRC connection resetting message including makeBeforeBreak-r16 with a value of false (False). In addition, the fact that makeBeforeBreak-r16 is not set may be, for example, in the case of NR, an RRC reconfiguration message in which makeBeforeBreak-r16 is not included in the field of the synchronization reconfiguration information element.

[0326] In addition, the setting of makeBeforeBreak-r16 may be, for example, in the case of EUTRA, UE122 receives the RRC connection reconfiguration message including makeBeforeBreak-r16 in the radio resource configuration (radioBearerConfigDedicated) information element specific to the terminal device. In addition, the setting of makeBeforeBreak-r16 may be, for example, in the case of NR, receiving the RRC reconfiguration message including makeBeforeBreak-r16 in the field of the data radio bearer configuration information element.

[0327] makeBeforeBreak-r16 may have, for example, an enumerated type value including true, or may have, as a value, an information element including information required for make-before-break switching.

[0328] Furthermore, the condition (E) may be the following (E2).

[0329] (E2) When the timer T300, the timer T301, the timer T304, and the timer T311 are not running, a notification indicating that the retransmission of the SRB or DRB has reached the maximum number of retransmissions is received from the RLC layer of the MCG, or under the first condition, when the timer T304 is running, a notification indicating that the retransmission of the SRB or DRB has reached the maximum number of retransmissions is received from the RLC layer of the MCG.

[0330] When UE122 determines that a radio link failure is detected in the MCG, it stores various information as radio link failure information. Then, if the security of the AS is not activated, the release reason can be set to "other" to start the process of leaving RRC_CONNECTED.

[0331] In addition, in the case of AS security activation, if under the first condition, the sending of part or all of the SRB and / or DRB of the MCG can be suspended, and the MAC entity of the MCG can be reset.

[0332] In addition, in the case of AS security activation, if it is not under the first condition, the RRC connection re-establishment process is started.

[0333] The RRC connection re-establishment process may be initiated when any of the following conditions (A) to (E) are met.

[0334] (A) When the MCG radio link fails when the MCG radio link fails under the first condition

[0335] (B) When the switching fails (when the synchronization resetting in MCG fails in NR)

[0336] (C) When migration to another RAT fails

[0337] (D) When the lower layer is notified of the failure of the integrity check related to SRB1 or SRB2

[0338] (E) When resetting the RRC connection fails

[0339] In addition, when any of the above conditions is met, under the first condition, and when no wireless link failure is detected in the MCG of the switching source, the RRC connection re-establishment process may not be started, and the process of notifying the switching failure in the MCG of the switching source may be started.

[0340] If the first condition is that makeBeforeBreak-r16 is set for UE 122, the set makeBeforeBreak-r16 may be released when timer T304 expires or when the process of notifying a handover failure in the MCG of the handover source is started.

[0341] When the RRC connection re-establishment procedure starts, UE 122 performs part or all of the following processes (A) to (J).

[0342] (A) If timer T310 is running, stop timer T310

[0343] (B) If timer T312 is running, stop timer T312

[0344] (C) If timer T313 is running, stop timer T313

[0345] (C) If timer T314 is running, stop timer T314

[0346] (D) Start timer T311

[0347] (E) Suspend all RBs except SRB0

[0348] (F) Reset MAC

[0349] (G) If set, release the SCell of MCG

[0350] (H) Apply the default physical channel settings

[0351] (I) Apply the default MAC master settings to MCG

[0352] (J) Execute cell selection process

[0353] Next, the following situation is studied: after UE122 sends an RRC connection re-configuration completion message or an RRC re-configuration completion message to the target cell during the switching process, data is sent and received via the cell groups of the switched MCG (also called Target MCG or Current MCG) and the switching source MCG (Source MCG) (the situation where actions are performed in the Dual protocol stack). An example of the processing in this case is shown. It should be noted that the following processing is not limited to the dual protocol stack situation, but can also be applied to other situations.

[0354] First, in the main cell of the SpCell serving as the source MCG, regardless of whether the timer T304 of the source MCG is running under a specific condition (first condition), the RRC layer processing unit of UE122 can start (Start) or restart (Restart) the timer (T310) of the source MCG when receiving the out-of-synchronization notification from the physical layer processing unit of the source MCG for a predetermined number of consecutive times (N310 times). In addition, the RRC layer processing unit of UE122 can stop (Stop) the timer (T310) when receiving the synchronization from the physical layer processing unit of the source MCG for a predetermined number of consecutive times (N311 times). In addition, in the judgment of starting or restarting the timer T310, the condition that the timer T300 of the source MCG, the timer T301 of the source MCG, and the timer T311 of the source MCG are not running can be added.

[0355] The RRC layer processing unit of UE122 determines that a radio link failure is detected in the source MCG when any of the following conditions (A) to (E) are met.

[0356] (A) When the source MCG's timer T310 expires (Expire)

[0357] (B) When the source MCG's timer T312 expires

[0358] (C) When the source MCG's timer T300, timer T301, timer T304, and timer T311 are not running, a notification (indication) of a random access problem is received from the source MCG's MAC entity.

[0359] (D) Under the first condition, when the source MCG's timer T304 is running and a notification of a random access problem is received from the source MCG's MAC entity

[0360] (E) When receiving a notification from the RLC layer of the source MCG indicating that the retransmission of SRB or DRB has reached the maximum number of retransmissions

[0361] The first condition may be that makeBeforeBreak-r16 is set for UE 122 .

[0362] In addition, the first condition may be that either makeBeforeBreak-r14 or makeBeforeBreak-r16 is set for UE 122 .

[0363] Furthermore, the condition (E) may be the following (E2).

[0364] (E2) When the timer T300, timer T301, timer T304, and timer T311 of the source MCG are not running, a notification indicating that the retransmission of the SRB or DRB has reached the maximum number of retransmissions is received from the RLC layer of the source MCG, or under the first condition, when the timer T304 is running, a notification indicating that the retransmission of the SRB or DRB has reached the maximum number of retransmissions is received from the RLC layer of the source MCG.

[0365] When UE122 determines that a radio link failure is detected in the source MCG, it may suspend the transmission of part or all of the SRB and / or DRB of the source MCG and reset the MAC entity of the source MCG.

[0366] UE 122 may regard the current MCG as the source MCG when makeBeforeBreak-r16 is set in the current MCG.

[0367] In addition, when the initial uplink grant is allocated through the PDCCH in the handover destination cell, the UE 122 may regard the handover source MCG as the source MCG.

[0368] In addition, UE 122 may regard the MCG of the switching source as the source MCG when the RRC reconfiguration complete message is sent.

[0369] In addition, UE122 can regard the MCG of the switching source as the source MCG when receiving the UE contention resolution identity MAC control element from the target gNB.

[0370] In addition, when makeBeforeBreak-r16 is set in the current MCG, UE122 can release the MCG if a source MCG already exists and regard the current MCG as a new source MCG.

[0371] In this way, unnecessary re-establishment processing in MBB-HO can be prevented by identifying the processing of detecting the radio link failure of the source MCG and the processing of detecting the radio link failure of the current MCG, and efficient mobility can be achieved.

[0372] An example of the action of MBB-HO is described. Here, an example of using an RRC reconfiguration message including a CellGroupConfig including a synchronization reconfiguration information element in NR is shown. It should be noted that in the description of each process described below, there is a description of receiving an information element, which, unless otherwise specified, may also mean that the information element is included in the RRC reconfiguration message that triggers each process. In addition, unless otherwise specified, the information elements used in each process can correspond to the information elements used in non-patent document 10.

[0373] The terminal device performs process A based on the received CellGroupConfig information element. Furthermore, the terminal device performs process L based on the received masterKeyUpdate information element. Furthermore, the terminal device performs process I based on the received RadioBearerConfig information element.

[0374] It should be noted that each item of each process described below is marked with an indentation and a symbol. For example, process A, process B, process C, and process H are respectively Fig.16 , Fig.17 , Fig.18 , Fig.19 The process shown in FIG. 1 is explained in the manner of the process shown in FIG. 2 , but other processing is explained in the same manner.

[0375] (Process A) The following process is performed based on the received CellGroupConfig information element.

[0376] (A-0) If CellGroupConfig includes SpCell configuration information (spCellConfig information element) including synchronization reconfiguration information, and the synchronization reconfiguration information includes information indicating that the RRC reconfiguration is MBB-HO (e.g., MakeBeforeBreak-r16), then

[0377] (A-0-1) The current terminal device settings (source settings) are copied as the target settings. Unless otherwise specifically stated, the following subsequent processing can be performed on the copied target settings. For example, in the case of MBB-HO, the "current terminal device settings" of each process can be regarded as the "target settings of the current terminal device". In addition, for example, the settings to be copied may include (1) settings related to the bearer (for example, settings related to SRB, settings related to DRB, etc.), (2) settings of the cell group (for example, settings of SpCell, settings of SCell, settings of each entity, etc.), (3) variables stored inside the terminal device (measurement settings (VarMeasConfig), measurement results (VarMeasReportList), timers, counters, etc.), and (4) part or all of the security-related settings (for example, various keys). In addition, the bearer settings to be copied may not include settings related to SRB. That is, with respect to DRB, both the source settings and the target settings can be managed, and with respect to SRB, the settings can be switched from the source settings to the target settings instead of being copied. In addition, information that can determine whether to copy the SRB setting may be included in the RRC resetting message including the synchronous resetting. For example, the information may be included in MakeBeforeBreak-r16.

[0378] (A-1) If CellGroupConfig includes the configuration information of SpCell (spCellConfig information element) including synchronization reconfiguration information, then

[0379] (A-1-1) Execute the processing B described later.

[0380] (A-1-2) If the state is suspended, all suspended radio bearers are resumed, and transmission in the SCG for all radio bearers is resumed.

[0381] (A-2) If CellGroupConfig includes a list of released RLC bearers (rlc-BearerToReleaseList information element), then

[0382] (A-2-1) Execute the processing C described later.

[0383] (A-3) If CellGroupConfig includes a list of RLC bearers to be added and / or modified (rlc-BearerToAddModList information element), then

[0384] (A-3-1) Execute the processing D described later.

[0385] (A-4) If CellGroupConfig includes the MAC settings for the cell group (mac-CellGroupConfig information element), then

[0386] (A-4-1) Configure the MAC entity of the cell group in the later described process E. It should be noted that in each embodiment of the present invention, the terminal device "configures" using the information element included in the RRC message, which may be the application of the information included in the information element to the terminal device configuration.

[0387] (A-5) If CellGroupConfig includes a list of SCells to be released (sCellToReleaseList information element), then

[0388] (A-5-1) The SCell is released in the process F described later.

[0389] (A-6) If CellGroupConfig includes SpCell configuration information (spCellConfig information element), then

[0390] (A-6-1) SpCell is set in the process G described later.

[0391] (A-7) If CellGroupConfig includes a list of SCells to be added and / or modified (sCellToAddModList information element), then

[0392] (A-7-1) In the process H described later, the SCell is added and / or changed.

[0393] (Process B)

[0394] (B-1) If the security of the AS is not activated, a process of transitioning to RRC_IDLE is performed and process B is terminated.

[0395] (B-2) If it is running, stop the timer T310 of the corresponding SpCell.

[0396] (B-3) By synchronously resetting the timer value of t304 included in the resetting, the timer T304 of the corresponding SpCell is started.

[0397] (B-4) If frequency information (frequencyInfoDL) is included, then

[0398] (B-4-1) The target SpCell is regarded as the cell of the physical cell identifier indicated by the physical cell identifier information (physCellId) included in the synchronization reconfiguration at the SSB frequency indicated by frequencyInfoDL.

[0399] (B-5) Otherwise,

[0400] (B-5-1) The target SpCell is regarded as the cell of the physical cell identifier indicated by the physical cell identifier information (physCellId) included in the synchronization reconfiguration at the SSB frequency of the source SpCell.

[0401] (B-6) Start synchronization of the target SpCell to the downlink.

[0402] (B-7) Apply the established BCCH settings.

[0403] (B-8) If necessary, obtain a master information block (MIB) which is one of the broadcast information.

[0404] (B-9) If the synchronization re-establishment includes information indicated as MBB-HO,

[0405] (B-9-1) If no MAC entity exists in the target cell group, then

[0406] (B-9-1-1) Generate a MAC entity for the target cell group (referred to simply as target MAC entity).

[0407] (B-9-2) Apply the established (default) MAC cell group settings to the target MAC entity.

[0408] (B-9-3) If set, the SCell of the target cell group is regarded as a deactivated state (Deactivated state).

[0409] (B-9-4) The value of newUE-Identity is used as the C-RNTI of the target cell group.

[0410] (B-10) Otherwise,

[0411] (B-10-1) Reset the MAC entity of the cell group.

[0412] (B-10-2) If set, the SCell of the cell group is considered to be in a deactivated state (Deactivated state).

[0413] (B-10-3) Apply the value of newUE-Identity as the C-RNTI of the cell group.

[0414] (B-11) The lower layer is set based on the setting (spCellConfigCommon) of SpCell included in the synchronous resetting.

[0415] (B-12) If necessary, set the lower layer based on other information included in the synchronization reset.

[0416] (Process C)

[0417] (C-1a) As part of the current terminal device configuration, the value of the logical channel identifier (logicalChannelIdentity) included in rlc-BearerToReleaseList, or

[0418] (C-1b) As a result of the release of the SCG, for each of the values ​​of the released logical channel identifiers,

[0419] (C-1-1) Release the corresponding logical channel and the RLC entity associated with the logical channel.

[0420] (Processing D)

[0421] The following processing is performed on the RLC bearer configuration (RLC-BearerConfig) included in the received rlc-BearerToAddModList information element.

[0422] (D-1) If the current terminal device configuration includes the RLC bearer of the received logical channel identifier,

[0423] (D-1-1) If information indicating reestablishment of RLC is received (reestablishRLC), then

[0424] (D-1-1-1) Re-establishing the RLC entity

[0425] (D-1-2) Reconfigure the RLC entity according to the received RLC configuration (rlc-Config).

[0426] (D-1-3) Reconfigure the logical channel according to the received MAC logical channel configuration (mac-LogicalChannelConfig).

[0427] (D-2) Otherwise,

[0428] (D-2-1) If the logical channel identifier for SRB and the RLC settings are included, then

[0429] (D-2-1-1) Establish an RLC entity according to the established (default) settings.

[0430] (D-2-2) Otherwise,

[0431] (D-2-2-1) Establish an RLC entity based on the received RLC settings (rlc-Config).

[0432] (D-2-3) If a logical channel identifier and a MAC logical channel setting for an SRB are included, then

[0433] (D-2-3-1) According to the established (default) settings, set the MAC entity corresponding to the logical channel.

[0434] (D-2-4) Otherwise,

[0435] (D-2-4-1) According to the received MAC logical channel setting, set the MAC entity corresponding to the logical channel.

[0436] (D-2-5) Based on the identifier information (servedRadioBearer) of the radio bearer included in the setting of the RLC bearer, the logical channel is associated with the PDCP entity.

[0437] (Processing E)

[0438] (E-1) If the CellGroupConfig is to be reconfigured to the SCG, and the SCG MAC is not part of the current terminal device configuration, then

[0439] (E-1-1) Generate SCG MAC entity.

[0440] (E-2) Reconfigure the MAC main configuration (MAC main configuration) of the cell group based on the MAC cell group configuration (mac-Cell) other than the configuration related to the addition, modification and / or release of the timing advance group (TAG).

[0441] (E-3) If the received MAC cell group setting includes information related to the release of the TAG (tag-ToReleaseList),

[0442] (E-3-1) If the identifier of the TAG included in tag-ToReleaseList is part of the current terminal device's settings, for each TAG identifier, release the TAG indicated by the TAG identifier.

[0443] (E-4) If the received MAC cell group setting includes information related to the addition and / or modification of TAGs (tag-ToAddModList),

[0444] (E-4-1) If the identifiers of the tags included in tag-ToAddModList are not part of the current terminal device's settings, for each tag identifier,

[0445] (E-4-1-1) Add a TAG corresponding to the TAG identifier according to the received timing advance timer.

[0446] (E-4-2) If the tag identifiers included in tag-ToAddModList are part of the current terminal device settings, for each tag identifier,

[0447] (E-4-2-1) Reset the TAG corresponding to the TAG identifier according to the received timing advance timer.

[0448] (Processing F)

[0449] (F-1) If the release is triggered by receiving the SCell release list (sCellToReleaseList), then

[0450] (F-1-1) For the value of each SCell index (sCellIndex) included in sCellToReleaseList,

[0451] (F-1-1-1) If the existing terminal device configuration includes an SCell having a value of sCellIndex, then

[0452] (F-1-1-1-1) Release the SCell.

[0453] (Processing G)

[0454] (G-1) If the SpCell configuration includes information about timers and constants related to radio link failure (RLF) (rlf-TimersAndConstants), then

[0455] (G-1-1) According to rlf-TimersAndConstants,

[0456] Set the timer and constants for RLF for this cell group.

[0457] (G-2) Otherwise, if rlf-TimersAndConstants is not set for the cell group, then

[0458] (G-2-1) Use the values ​​of the timer and constant received through the system information to set the timer and constant for the RLF of the cell group.

[0459] (G-3) If the SpCell configuration includes a dedicated SpCell configuration (spCellConfigDedicated), then

[0460] (G-3-1) Set SpCell according to spCellConfigDedicated.

[0461] (G-3-2) If set, the BWP indicated by the identifier of the first activated uplink BWP (Bandwidth part) (firstActiveUplinkBWP-Id) is regarded as the activated uplink BWP.

[0462] (G-3-3) If set, the BWP indicated by the identifier of the first activated downlink BWP (Bandwidth part) (firstActiveDownlinkBWP-Id) is regarded as the activated downlink BWP.

[0463] (G-3-4) If the reference signal for wireless link monitoring is reset according to the received dedicated SpCell setting,

[0464] (G-3-4-1) If it is running, stop the timer T310 corresponding to SpCell.

[0465] (G-3-4-2) Stop counters N310 and N311.

[0466] (Processing H)

[0467] (H-1) For each value of sCellIndex included in sCellToAddModList that is not part of the current terminal device settings,

[0468] (H-1-1) Add the SCell corresponding to sCellIndex.

[0469] (H-1-2) The lower layer is set in such a way that the SCell is regarded as an inactive state.

[0470] (H-1-3) for each measurement identifier in the list (measIdList) of measurement identifiers storing the variables (VarMeasConfig) for the measurement settings,

[0471] (H-1-3-1a) If the SCell is not applicable to the measurement corresponding to the measurement identifier, and

[0472] (H-1-3-1b) If the SCell is included in the list of triggered cells (cellsTriggeredList) defined by the variable (VarMeasReportList) storing the measurement report for the measurement identifier, then

[0473] (H-1-3-1-1) Delete the SCell from the list of triggered cells (cellsTriggeredList) defined by the variable (VarMeasReportList) storing the measurement report for the measurement identifier.

[0474] (H-2) For each value of sCellIndex included in sCellToAddModList that is part of the current terminal device settings,

[0475] (H-2-1) Change the setting of SCell corresponding to sCellIndex.

[0476] (Processing I)

[0477] (I-1) If RadioBearerConfig includes srb3-ToRelease, then

[0478] (I-1-1) Release the PDCP entity and SRB identifier of SRB3.

[0479] (I-2) If RadioBearerConfig includes SRB-ToAddModList, then

[0480] (I-2-1) Add and / or reconfigure SRBs.

[0481] (I-3) If RadioBearerConfig includes drb-ToReleaseList, then

[0482] (I-3-1) The DRB is released in the process J described later.

[0483] (I-4) If RadioBearerConfig includes DRB-ToAddModList, then

[0484] (I-4-1) In the process K described later, the DRB is added and / or reconfigured.

[0485] (I-5) All SDAP entities that are not associated with the DRB are released, and the upper layer is notified of the release of the user plane resources of the PDU session corresponding to the released SDAP entity.

[0486] In the process I, in the case of MBB-HO, in the process of adding, resetting and / or releasing the SRB, two settings, the source setting and the target setting, can be managed, and the target setting is not processed in processes I-1 and I-2, but the current SRB setting is reset in processes I-1 and I-2. That is, the SRB can manage one setting. In this case, the SRB setting of the source before the reset can be saved separately to prevent handover failure, etc.

[0487] As the processing I-5, in the case of MBB-HO, all SDAP entities not associated with any of the DRBs set by the source and the DRBs set by the target may be released, and the release of the user plane resources of the PDU session associated with the released SDAP entity may be notified to the upper layer. For example, MBB-HO may be performed based on an RRC reconfiguration message including synchronous reconfiguration, and in the target cell, until a message (such as an RRC message, a MAC CE, etc.) is received to release the source's settings, the SDAP entity corresponding to either or both of the source's DRB and the target's DRB is not released, but when a message is received to release the source's settings to release the source's DRB, all SDAP entities not associated with the (target's) DRB are released, and the release of the user plane resources of the PDU session associated with the released SDAP entity is notified to the upper layer.

[0488] The above-mentioned "receiving a message for releasing the setting of the source" can be renamed as detecting a certain request. The certain request can be renamed as a certain information. Detecting a certain request can be that a specific information element (such as an information element indicating the release of the setting of the source) is included in the received RRC message, or that a specific information (such as information indicating the release of the setting of the source) is included in the received MAC control element, or that the first uplink authorization is accepted in SpCell. Detecting a certain request can be that the random access procedure has been successful. Detecting a certain request can also be that the random access procedure has been successful in either or both of the following cases: (A) the synchronous reconfiguration is included in the SpCellConfig, or (B) the random access procedure is triggered by providing (submitting) the RRC entity to the lower layer to send a message notifying the completion of the RRC reconfiguration (for example, if in LTE, it is an RRC connection reconfiguration completion message, and if in NR, it is an RRC reconfiguration completion message). In addition, detecting a certain request can also be any one of those detected by installing the terminal device.

[0489] (Processing J)

[0490] (J-1a) for each DRB identifier included in the drb-ToReleaseList that is part of the current terminal device's configuration, or

[0491] (J-1b) for each DRB identifier released as a result of full configuration,

[0492] (J-1-1) Release the PDCP entity and DRB identifier.

[0493] (J-1-2) If an SDAP entity is set to be associated with this DRB, then

[0494] (J-1-2-1) Instruct the SDAP associated with the DRB to release the DRB.

[0495] (J-1-3) If the DRB is associated with the identifier of the EPS bearer,

[0496] (J-1-3-1) If no new bearer is added to either NR or E-UTRA with the same EPS bearer identifier, then

[0497] (J-1-3-1-1) Notify the upper layer of the release of the DRB and the EPS bearer identifier of the released DRB.

[0498] As the process J-1-3-1, in the case of MBB-HO, if a new bearer is not added in any of the source and target settings for the same EPS bearer, the release of the DRB and the EPS bearer identifier of the released DRB may be notified to the upper layer. For example, MBB-HO may be performed based on an RRC reconfiguration message including synchronous reconfiguration, and in the target cell, until a message (such as an RRC message, a MAC CE, etc.) is received to release the source setting, if the bearer association is not added in any of the source and target settings for the same EPS bearer, the release of the DRB and the EPS bearer identifier of the released DRB are not notified to the upper layer, but when a message (such as an RRC message, a MAC CE, etc.) is received to release the source setting and the source DRB is released, if a new bearer is not added in any of the NR and the E-UTR in the same EPS bearer identifier, the release of the DRB and the EPS bearer identifier of the released DRB are not notified to the upper layer.

[0499] (Processing K)

[0500] (K-1) for each DRB identifier included in DRB-ToAddModList that is not part of the current terminal device's configuration,

[0501] (K-1-1) Establish a PDCP entity and configure the PDCP entity according to the received PDCP settings (pdcp-Config).

[0502] (K-1-2) If the PDCP entity for the DRB is not set to ciphering disabled,

[0503] (K-1-2-1a) If the target RAT of the handover is E-UTRA / 5GC, or

[0504] (K-1-2-1b) If the terminal device is connected only to E-UTRA / 5GC, then

[0505] (K-1-2-1-1) Use the encryption algorithm and key setting of non-patent document 4 to set up the PDCP entity.

[0506] (K-1-2-2) Otherwise,

[0507] (K-1-2-2-1) By setting the PDCP entity according to the encryption algorithm of the security setting (securityConfig), the key represented by the parameter (keyToUse) associated with the primary key (KeNB or KgNB) or the secondary key (S-KgNB) is applied.

[0508] (K-1-3) If the PDCP entity of the DRB is configured to perform integrity protection, then

[0509] (K-1-3-1) By configuring the PDCP entity according to the integrity protection algorithm of the security setting (securityConfig), the key represented by the parameter (keyToUse) associated with the primary key (KeNB or KgNB) or the secondary key (S-KgNB) is applied.

[0510] (K-1-4) If SDAP settings (sdap-Config) are included,

[0511] (K-1-4-1) If there is no SDAP for the received PDU session, then

[0512] (K-1-4-1-1) Establish SDAP entity.

[0513] (K-1-4-1-2) If there is no SDAP for the received PDU session prior to the reception of this reset, then

[0514] (K-1-4-1-2-1) Notify the upper layer of the establishment of user plane resources for the PDU session.

[0515] (K-1-4-2) Set the SDAP entity according to the received SDAP setting, and associate the DRB with the SDAP entity.

[0516] (K-1-5) If the DRB is associated with an EPS bearer identifier,

[0517] (K-1-5-1) If a DRB is configured by NR or E-UTRA before receiving this reconfiguration in the same EPS bearer identifier, then

[0518] (K-1-5-1-1) Associate the established DRB with the corresponding EPS bearer identifier.

[0519] (K-1-5-2) Otherwise,

[0520] (K-1-5-2-1) Notify the upper layer of the establishment of the DRB and the EPS bearer identifier of the established DRB.

[0521] (K-2) for each DRB identifier included in the DRB-ToAddModList that is part of the current terminal device's configuration,

[0522] (K-2-1) If the parameter reestablishPDCP is set,

[0523] (K-2-1-1a) If the RAT of the handover target is E-UTRA / 5GC, or

[0524] (K-2-1-1b) If the terminal device is connected only to E-UTRA / 5GC,

[0525] (K-2-1-1-1) If the PDCP entity that has not set the DRB with cipheringDisabled is not configured, then

[0526] (K-2-1-1-1-1) Use the encryption algorithm and key setting of non-patent document 4 to set up the PDCP entity.

[0527] (K-2-1-2) Otherwise,

[0528] (K-2-1-2-1) If the PDCP entity for this DRB is not set to ciphering disabled, then

[0529] (K-2-1-2-1-1) By setting the PDCP entity according to the encryption algorithm of the security setting (securityConfig), the key represented by the parameter (keyToUse) associated with the primary key (KeNB or KgNB) or the secondary key (S-KgNB) is applied.

[0530] (K-2-1-2-2) If the PDCP entity of the DRB is configured to perform integrity protection, then

[0531] (K-2-1-2-2-1) The PDCP entity is configured according to the integrity protection algorithm of the security configuration (securityConfig), and the key indicated by the parameter (keyToUse) associated with the primary key (KeNB or KgNB) or the secondary key (S-KgNB) is applied.

[0532] (K-2-1-3) If drb-ContinueROHC is included in pdcp-Config, then

[0533] (K-2-1-3-1) Notify the lower layer that drb-ContinueROHC is set.

[0534] (K-2-1-4) Re-establish the PDCP entity of the DRB.

[0535] (K-2-2) Otherwise, if recoverPDCP is configured,

[0536] (K-2-2-1) Trigger the execution of data recovery for the PDCP entity of this DRB.

[0537] (K-2-3) If PDCP settings are included, then

[0538] (K-2-3-1) Reconfigure the PDCP entity according to the received PDCP settings.

[0539] (K-2-4) If SDAP settings are included, then

[0540] (K-2-4-1) Reconfigure the SDAP entity according to the received SDAP settings.

[0541] (K-2-4-2) For each QFI added through mappedQoS-FlowsToAdd, if a QFI value is set, the QFI value is released from the old DRB.

[0542] As the process K-1-4-1-2, in the case of MBB-HO, if the SDAP of the received PDU session does not exist in the setting of the source and the setting of the target before receiving the re-setting, the establishment of the user plane resources for the PDU session may be notified to the upper layer. Alternatively, as the process K-1-4-1-2, in the case of MBB-HO, if the SDAP of the received PDU session does not exist in the setting of the source before receiving the re-setting, the establishment of the user plane resources for the PDU session may be notified to the upper layer.

[0543] In the process K-1-5-2, in the case of MBB-HO, if DRB is not set for the same bearer identifier by NR or E-UTRA in both the source setting and the target setting before receiving the reconfiguration, the establishment of the DRB and the EPS bearer identifier of the established DRB may be notified to the upper layer. Alternatively, in the process K-1-5-2, in the case of MBB-HO, if DRB is not set for the same bearer identifier by NR or E-UTRA in the source setting before receiving the reconfiguration, the establishment of the DRB and the EPS bearer identifier of the established DRB may be notified to the upper layer.

[0544] (Processing L)

[0545] (L-1) If the terminal device is connected to E-UTRA / EPC,

[0546] (L-1-1) If sk-Counter is included, then

[0547] (L-1-1-1) Update the S-KgNB key based on the KgNB key and the received sk-Counter.

[0548] (L-1-1-2) Generate (Derive: derive) KRRCenc key and KUPenc key. KRRCenc key is a key for protecting the RRC signal generated from KgNB by the encryption algorithm. In addition, KUPenc is a key for protecting the service (user data) of the user plane generated from KgNB by the encryption algorithm.

[0549] (L-1-1-3) Generate KRRCint key and KUPint key based on KgNB key. KRRCint key is a key used to protect the RRC signal generated from KgNB through the integrity algorithm. In addition, KUPint is a key used to protect the user plane service (user data) generated from KgNB through the integrity algorithm.

[0550] (L-2) Otherwise,

[0551] (L-1-2) If the received masterKeyUpdate includes nas-Container, then

[0552] (L-1-2-1) Forward the nas-Container to the upper layer.

[0553] (L-1-3) If keySetChangeIndicator is true, then

[0554] (L-1-3-1) Generate or update KgNB based on KAMF.

[0555] (L-1-4) Otherwise,

[0556] (L-1-4-1) Generate or update the KgNB key based on the current KgNB key or NextHop (NH).

[0557] (L-1-5) stores the value of nextHopChainingCount.

[0558] (L-1-6) Generate a key associated with the KgNB key as follows.

[0559] (L-1-6-1) If SecurityConfig includes securityAlgorithmConfig, then

[0560] (L-1-6-1-1) Generate the KRRCenc key and KUPenc key associated with the cipheringAlgorithm included in securityAlgorithmConfig based on the KgNB key.

[0561] (L-1-6-1-2) Generate the KRRCint key and KUPint key associated with the integrityProtAlgorithm included in securityAlgorithmConfig based on the KgNB key.

[0562] (L-1-6-2) Otherwise,

[0563] (L-1-6-2-1) Generate the KRRCenc key and KUPenc key associated with the current cipheringAlgorithm based on the KgNB key.

[0564] (L-1-6-2-2) Generate the KRRCint key and KUPint key associated with the current integrityProtAlgorithm based on the KgNB key.

[0565] An example of the action of MBB-HO is described. Here, an example of using an RRC connection re-setup message including a mobility control information (mobilityControlInfo) information element in LTE is shown. It should be noted that in the description of each process described below, there is a description of receiving an information element, but unless otherwise specified, it can also mean that the information element is included in the RRC connection re-setup message that triggers each process. In addition, unless otherwise specified, the information elements used in each process can correspond to the information elements used in non-patent document 4.

[0566] The terminal device receives an RRC connection reconfiguration message including mobilityControlInfo. If the terminal device can comply with the settings included in the message, the following process LA is performed.

[0567] (Processing LA)

[0568] (LA-1) Start timer T304 using the timer value of t304 included in mobilityControlInfo.

[0569] (LA-2) If carrierFreq is included, then

[0570] (LA-2-1) The physical cell identifier on the frequency indicated by carrierFreq regards the cell indicated by targetPhysCellId as the target PCell.

[0571] (LA-3) Otherwise,

[0572] (LA-3-1) The physical cell identifier on the frequency of the source PCell regards the cell indicated by targetPhysCellId as the target PCell.

[0573] (LA-4) Start downlink synchronization toward the target PCell.

[0574] (LA-5-1) After stopping uplink transmission and / or downlink reception with the source cell, the terminal device performs the remaining processing of the procedure including resetting of the MAC.

[0575] (LA-6) If makeBeforeBreak-r16 is set, then

[0576] (LA-6-1) The current terminal device settings (source settings) are copied as target settings. Unless otherwise specifically stated, the following re-setting process can be performed on the copied target settings. For example, in the case of MBB-HO, the "current terminal device settings" of each process can be regarded as the "target settings of the current terminal device". In addition, for example, the settings to be copied may include (1) bearer settings (such as SRB settings, DRB settings, etc.), (2) cell group settings (such as SpCell settings, SCell settings, RLC entity settings, MAC entity settings, PHY settings, etc.), (3) internal variables (measurement settings (VarMeasConfig), measurement results (VarMeasReportList), timers, counters, etc.), (4) security-related settings (for example, various keys) in part or all. In addition, the SRB settings may not be included in the bearer settings to be copied. That is, regarding DRB, both the source setting and the target setting can be managed, and regarding SRB, the setting can be switched from the source setting to the target setting instead of being copied. In addition, information that can determine whether to copy the SRB setting can be included in the RRC connection resetting message including mobilityControlInfo. For example, the information can be included in MakeBeforeBreak-r16.

[0577] (LA-7) If set, reset the MAC of MCG and the MAC of SCG. When MakeBeforeBreak-r16 is set, the MAC of MCG and the MAC of SCG of the source may not be reset. Alternatively, when MakeBeforeBreak-r16 is set, the MAC of the source may not be reset, but the MAC of the target may be reset.

[0578] (LA-8) Re-establish PDCP for all radio bearers that are set and established through PDCP settings. When MakeBeforeBreak-r16 is set, the re-establishment of PDCP is applied only to the target PDCP. Alternatively, in the case of Single PDCP described later, if MakeBeforeBreak-r16 is set, if there is already a PDCP associated with the target radio bearer, the establishment and / or re-establishment of PDCP may not be performed. That is, if MakeBeforeBreak-r16 is set, if there is no PDCP associated with the target radio bearer, the establishment and / or re-establishment of PDCP may be performed.

[0579] (LA-9) For all established radio bearers, if configured, re-establish the RLC of the MCG and the RLC of the SCG.

[0580] (LA-10) Use the value of newUE-Identity as C-RNTI.

[0581] (LA-11) Set the lower layer based on the received cell-common radio resource configuration (radioResourceConfigCommon).

[0582] (LA-12) Set the lower layer according to other information included in the received mobilityControlInfo.

[0583] (LA-13) If the received RRC Connection Reconfiguration message includes sCellToReleaseList, then

[0584] (LA-13-1) Perform release of SCell.

[0585] (LA-14) If the received RRC Connection Reset Message includes sCellGroupToReleaseList, then

[0586] (LA-14-1) Execute release of SCell group.

[0587] (LA-15a) If the received RRC Connection Reconfiguration message includes scg-Configuration, or

[0588] (LA-15b) If the current terminal device configuration includes more than one Split DRB, and the received RRC Connection Reconfiguration message includes DRB-ToAddModList, then

[0589] (LA-15-1) Performed reconfiguration of SCG.

[0590] (LA-16) If the received RRC Connection Reconfiguration message includes a terminal device-specific radio resource configuration (radioResourceConfigDedicated), then

[0591] (LA-16-1) Perform wireless resource configuration in the processing LB described later.

[0592] (LA-17) If the RRC Connection Reconfiguration message includes security configuration (securityConfigHO-v1530),

[0593] (LA-17-1) If nas-Container is received, then

[0594] (LA-17-1-1) Transfer the nas-Container to the upper layer.

[0595] (LA-17-2) If keyChangeIndicator-r15 is received and keyChangeIndicator-r15 is true, then

[0596] (LA-17-2-1) Update KeNB key based on KAMF key.

[0597] (LA-17-3) Otherwise,

[0598] (LA-17-3-1) Update the KeNB key based on the current KeNB or NextHop (NH).

[0599] (LA-17-4) Stores the value of nextHopChainingCount-r15.

[0600] (LA-17-5) If securityAlgorithmConfig-r15 is received, then

[0601] (LA-17-5-1) Generate the KRRCint key associated with the received integrityProtAlgorithm.

[0602] (LA-17-5-2) Generate the KRRCenc key and KUPenc key associated with the received cipheringAlgorithm. The KRRCenc key is a key used to protect the RRC signal generated from KeNB by the encryption algorithm. In addition, KUPenc is a key used to protect the user plane service (user data) generated from KeNB by the encryption algorithm.

[0603] (LA-17-6) Otherwise,

[0604] (LA-17-6-1) Generate the KRRCint key associated with the current integrityProtAlgorithm based on the KeNB key.

[0605] (LA-17-6-2) Generate the KRRCenc key and KUPenc key associated with the current cipheringAlgorithm based on the KeNB key.

[0606] (LA-18) If the received RRC Connection Reset Message includes sCellToAddModList, then

[0607] (LA-18-1) Perform addition and / or modification of SCells.

[0608] (LA-19) If the received RRC Connection Reset Message includes sCellGroupToAddModList, then

[0609] (LA-19-1) Perform addition and / or modification of SCell groups.

[0610] (LA-20) If the received RRC Connection Reconfiguration message includes measConfig, then

[0611] (LA-20-1) Perform measurement settings.

[0612] (LA-21) Perform automatic deletion of measurement identifiers.

[0613] (LA-22) Provide the RRC Connection Reconfiguration Complete message to the lower layer for transmission.

[0614] (LA-23) If the MAC is successful in the random access procedure, then

[0615] (LA-23-1) Stop timer T304 and end the process.

[0616] (Processing LB)

[0617] (LB-1) If the received radioResourceConfigDedicated includes SRB-ToAddModList, then

[0618] (LB-1-1) SRB addition and / or reconfiguration is performed in the processing LC described later.

[0619] (LB-2) If the received radioResourceConfigDedicated includes drb-ToReleaseList, then

[0620] (LB-2-1) DRB release is performed in the process LD described later.

[0621] (LB-3) If the received radioResourceConfigDedicated includes DRB-ToAddModList, then

[0622] (LB-3-1) Perform the addition and / or reconfiguration of DRB in the processing LE described later.

[0623] (LB-4) If the received radioResourceConfigDedicated includes mac-MainConfig, then

[0624] (LB-4-1) Execute the main setting of MAC in the process LF described later.

[0625] (Processing LC)

[0626] (LC-1) for each SRB identifier included in the SRB-ToAddModList that is not part of the current terminal device's configuration,

[0627] (LC-1-1) Establish the PDCP entity through the current security settings.

[0628] (LC-1-2) If rlc-BearerConfigSecondary is received with a value of "configuration", then

[0629] (LC-1-2-1) Establish a secondary MCG RLC entity based on the received rlc-BearerConfigSecondary and associate it with the DCCH logical channel.

[0630] (LC-1-2-2) The PDCP entity of E-UTRA is configured to activate duplication.

[0631] (LC-2) for each SRB identifier included in the SRB-ToAddModList that is part of the current terminal device's configuration,

[0632] (LC-2-1) If pdcp-verChange is included (i.e., change from NR PDCP to E-UTRA PDCP), then,

[0633] (LC-2-1-1) Establish the PDCP entity of E-UTRA through the current security settings.

[0634] (LC-2-1-2) Associate the primary RLC of the SRB with the established PDCP entity.

[0635] (LC-2-1-3) Release the NR PDCP of this SRB.

[0636] (LC-2-2) Reconfigure the main RLC entity according to the received rlc-Config.

[0637] (LC-2-3) Reconfigure the main DCCH logical channel according to the received logical channel configuration (logicalChannelConfig).

[0638] (LC-2-4) If rlc-BearerConfigSecondary with a value of "release" is included, then

[0639] (LC-2-4-1) Release the secondary MCG RLC entity and its associated DCCH logical channel.

[0640] (LC-2-5) If rlc-BearerConfigSecondary is received with a value of "configuration",

[0641] (LC-2-5-1) If the secondary RLC bearer is not included in the existing SRB configuration, then

[0642] (LC-2-5-1-1) Establish a secondary MCG RLC entity based on the received rlc-BearerConfigSecondary and associate it with the DCCH logical channel.

[0643] (LC-2-5-1-2) The PDCP entity of E-UTRA is configured to activate replication.

[0644] (LC-2-5-2) Otherwise,

[0645] (LC-2-5-2-1) Reconfigure the secondary MCG RLC entity according to the received rlc-BearerConfigSecondary to associate it with the DCCH logical channel.

[0646] (Processing LD)

[0647] (LD-1a) for each DRB identifier included in the drb-ToReleaseList that is part of the current terminal device's configuration, or,

[0648] (LD-2b) for each DRB identifier value released as a result of full configuration,

[0649] (LD-2-1) If the release of the DRB is a result of full setting, then

[0650] (LD-2-1-1) Release the PDCP entity of E-UTRA or NR.

[0651] (LD-2-2) Otherwise, if DRB is configured with PDCP configuration, then

[0652] (LD-2-2-1) Release the PDCP entity of E-UTRA.

[0653] (LD-2-3) Otherwise,

[0654] (LD-2-3-1) Re-establish the RLC entity for this DRB.

[0655] (LD-2-4) Release the RLC entity.

[0656] (LD-2-5) Release the DTCH logical channel.

[0657] (LD-2-6) If the terminal device is connected to the EPC,

[0658] (LD-2-6-1) If a DRB is configured with PDCP configuration and a new DRB is added to the same EPS bearer identifier via any of DRB-ToAddModList, nr-radioBearerConfig1, or nr-radioBearerConfig2,

[0659] (LD-2-6-1-1) If the process is triggered by switching, then

[0660] (LD-2-6-1-1-1) After the switch is successful, the release of the DRB and the EPS bearer identifier of the released DRB are notified to the upper layer.

[0661] (LD-2-6-1-2) Otherwise,

[0662] (LD-2-6-1-2-1) Immediately notify the upper layer of the release of the DRB and the EPS bearer identifier of the released DRB.

[0663] (Processing LE)

[0664] (LE-1) for each DRB identifier included in DRB-ToAddModList that is not part of the current terminal device's configuration,

[0665] (LE-1-1) If DRB-ToAddModListSCG is not received or DRB-ToAddModListSCG does not include the value of the DRB identifier,

[0666] (LE-1-1-1) If pdcp-Config is included, the PDCP entity is established according to the pdcp-Config and configured using the security settings of the current MCG.

[0667] (LE-1-1-2) If rlc-Confi is included, establish MCG RLC according to rlc-Config.

[0668] (LE-1-1-3) If a logical channel identifier (logicalChannelIdentity) and a logical channel setting (logicalChannelConfig) are included, an MCG DTCH logical channel is established according to the logicalChannelIdentity and logicalChannelConfig.

[0669] (LE-1-1-4) If rlc-BearerConfigSecondary with a value of "config" is included, then

[0670] (LE-1-1-4-1) According to rlc-BearerConfigSecondary, a secondary MCG RLC entity is established and associated with the DTCH logical channel. Then, the established RLC entity is associated with the E-UTRA PDCP with the same DRB identifier value in the current terminal device configuration.

[0671] (LE-1-2) If a DRB is configured in the same EPS bearer identifier, then

[0672] (LE-1-2-1) Associate the established DRB with the EPS bearer identifier.

[0673] (LE-1-3) Otherwise, if the entry in DRB-ToAddModList includes pdcp-config, (i.e., the bearer is established in PDCP of E-UTRA), then

[0674] (LE-1-3-1) Notify the upper layer of the establishment of the DRB and the EPS bearer identifier of the established DRB.

[0675] (LE-2) For each DRB identifier included in DRB-ToAddModList that is part of the current terminal device's configuration,

[0676] (LE-2-1) Reconfigure layers and / or bearers according to the included settings.

[0677] (Processing LF)

[0678] (LF-1) Reconfigure the MAC main configuration (MAC mainconfiguration) based on the MA main configuration information element (mac-MainConfig) except for the configuration related to the addition, modification and / or release of the secondary timing advance group (STAG).

[0679] (LF-2) If the received mac-MainConfig includes information related to the release of STAG (stag-ToReleaseList),

[0680] (LF-2-1) If the identifier of the STAG included in stag-ToReleaseList is part of the current terminal device's settings, release the STAG indicated by the identifier of the STAG for each STAG identifier.

[0681] (LF-3) If the received mac-MainConfig includes information related to the addition and / or modification of STAGs (stag-ToAddModList),

[0682] (LF-3-1) If the identifiers of the STAGs included in stag-ToAddModList are not part of the current terminal device's settings, then for each TAG identifier,

[0683] (LF-3-1-1) Add the STAG corresponding to the STAG identifier according to the received timeAlignmentTimerSTAG.

[0684] (LF-3-2) If the identifiers of the STAGs included in stag-ToAddModList are part of the current terminal device's settings, for each STAG identifier,

[0685] (LF-3-2-1) Reset the STAG corresponding to the STAG identifier according to the received timeAlignmentTimerSTAG.

[0686] Another example of the MBB-HO operation is described. Here, an example of using an RRC reconfiguration message including a conditional handover configuration in NR is shown.

[0687] For example, the RRC message sent by the base station device may include a conditional switching information element. The conditional switching information element may include a list of one or more information elements (conditional switching settings) including information included in the synchronization reconfiguration information element. In addition, the conditional switching information element may include an information element (conditional switching condition) indicating a condition for applying the conditional switching setting to each conditional switching setting or a part or all of the conditional switching settings.

[0688] The conditional switching setting may include part or all of the information included in RadioBearerConfig and CellGroupConfig. In addition, the conditional switching setting may include information indicating that it is MBB-HO. In addition, the conditional switching condition may include threshold information for using a reference signal to determine whether the condition is met. In addition, the conditional switching condition may also include information indicating that the conditional switching setting is applied immediately. For example, when the conditional switching condition indicates information indicating that the conditional switching setting is applied immediately, and information indicating that it is MBB-HO is added to the conditional switching setting, the processing A and processing I are performed based on the information included in the conditional switching setting, thereby enabling MBB-HO. Of course, in the case where the condition is met even when the conditional switching condition is other conditions, the processing A and processing I are performed based on the information included in the conditional switching setting, thereby enabling conditional MBB-HO.

[0689] In the MBB-HO of the NR, the terminal device can adopt a PDCP (Single PDCP) configuration that is common to the source and the target.

[0690] For example, in the case where the core network is 5GC, in the source setting, the logical channel, DRB (or SRB) and RLC bearer are associated through the RLC bearer setting, and then the DRB, PDCP entity and PDU session are associated through drb-ToAddMod. Similarly, in the target setting, the logical channel, DRB (or SRB) and RLC bearer are also associated through the RLC bearer setting, and then the DRB (or SRB), PDCP entity and PDU session are associated through drb-ToAddMod. In this case, for example, the logical channels, DRBs (or SRBs) and / or RLC bearers associated with the same DRB identifier (or SRB identifier) ​​in the source setting and the target setting can be associated with one PDCP. In addition, for example, the logical channels, DRBs (or SRBs) and / or RLC bearers associated with the same PDU session in the source setting and the target setting can be associated with one PDCP.

[0691] For example, in the case where the core network is 5GC, in the source setting, the logical channel, DRB (or SRB) and RLC bearer are associated through the RLC bearer setting, and then the DRB, PDCP entity and PDU session are associated through drb-ToAddMod. Similarly, in the target setting, the logical channel, DRB (or SRB) and RLC bearer are also associated through the RLC bearer setting, and then the DRB (or SRB), PDCP entity and PDU session are associated through drb-ToAddMod. In this case, for example, the logical channel, DRB (or SRB) and / or RLC bearer associated with the same DRB identifier (or SRB identifier) ​​in the source setting and the target setting can be associated with one SDAP.

[0692] In addition, for example, in the case where the core network is EPC, in the setting of the source, the DRB (or SRB), the PDCP entity, the logical channel, the RLC entity (and / or RLC bearer), and the EPS bearer are associated. Similarly, in the setting of the target, the DRB (or SRB), the PDCP entity, the logical channel, the RLC entity (and / or RLC bearer), and the EPS bearer are also associated. In this case, for example, the logical channel, the RLC entity (and / or RLC bearer) associated with the same DRB identifier (or SRB identifier) ​​in the setting of the source and the setting of the target can be associated with one PDCP entity. In addition, for example, the logical channel, the RLC entity (and / or RLC bearer), and the DRB (or SRB) associated with the same EPS bearer identifier in the setting of the source and the setting of the target can be associated with one PDCP.

[0693] In the above case, the terminal device may regard the PDCP settings of the source and the target associated with one PDCP as being the same. Alternatively, the terminal device may apply the PDCP settings of the target to the PDCP settings of the source.

[0694] In addition, in the case where a source's DRB (or SRB) and a target's DRB with the same DRB identifier are associated with one PDCP entity, the security keys (e.g., KUPenc, KUPint, KRRCenc and / or KRRCint, etc.) of the source and the target are different, and therefore multiple security keys are managed in one PDCP entity.

[0695] Another example of the MBB-HO operation is described. Here, an example of using an RRC connection reconfiguration message including a conditional handover setting in LTE is shown.

[0696] For example, the RRC message sent by the base station device may include a conditional switching information element. The conditional switching information element may include a list of one or more information elements (conditional switching settings) including information included in the mobilityControlInfo information element. In addition, the conditional switching information element may include an information element (conditional switching condition) indicating a condition for applying the conditional switching setting to each conditional switching setting or a part or all of the conditional switching settings.

[0697] The conditional switching setting may include part or all of the information included in the radio resource setting (radioBearerConfigCommon) common to the cell and the radio resource setting (radioBearerConfigDedicated) specific to the terminal device. In addition, the conditional switching setting may also include information indicating that it is MBB-HO (for example, MakeBeforeBreak-r16). In addition, the conditional switching condition may include threshold information for using a reference signal to determine whether the condition is met. In addition, the conditional switching condition may also include information indicating that the conditional switching setting is applied immediately. For example, when the conditional switching condition indicates information indicating that the conditional switching setting is applied immediately, and information indicating that it is MBB-HO is added to the conditional switching setting, the processing LA is performed based on the information included in the conditional switching setting, thereby enabling MBB-HO. Of course, in the case where the condition is met even when the conditional switching condition is other conditions, the processing LA is performed based on the information included in the conditional switching setting, thereby enabling conditional MBB-HO.

[0698] In the MBB-HO (MakeBeforeBreak-r16) of the LTE, the terminal device can adopt a PDCP (Single PDCP) configuration that is common to the source and the target.

[0699] For example, in the case where the core network is 5GC, in the source setting, the logical channel, DRB (or SRB) and RLC bearer are associated through the RLC bearer setting, and then the DRB, PDCP entity and PDU session are associated through drb-ToAddMod. Similarly, in the target setting, the logical channel, DRB (or SRB) and RLC bearer are also associated through the RLC bearer setting, and then the DRB (or SRB), PDCP entity and PDU session are associated through drb-ToAddMod. In this case, for example, the logical channels, DRBs (or SRBs) and / or RLC bearers associated with the same DRB identifier (or SRB identifier) ​​in the source setting and the target setting can be associated with one PDCP. In addition, for example, the logical channels, DRBs (or SRBs) and / or RLC bearers associated with the same PDU session in the source setting and the target setting can be associated with one PDCP.

[0700] For example, in the case where the core network is 5GC, in the source setting, the logical channel, DRB (or SRB) and RLC bearer are associated through the RLC bearer setting, and then the DRB, PDCP entity and PDU session are associated through drb-ToAddMod. Similarly, in the target setting, the logical channel, DRB (or SRB) and RLC bearer are also associated through the RLC bearer setting, and then the DRB (or SRB), PDCP entity and PDU session are associated through drb-ToAddMod. In this case, for example, the logical channel, DRB (or SRB) and / or RLC bearer associated with the same DRB identifier (or SRB identifier) ​​in the source setting and the target setting can be associated with one SDAP.

[0701] In addition, for example, in the case where the core network is EPC, in the setting of the source, the DRB (or SRB), the PDCP entity, the logical channel, the RLC entity (and / or RLC bearer), and the EPS bearer are associated. Similarly, in the setting of the target, the DRB (or SRB), the PDCP entity, the logical channel, the RLC entity (and / or RLC bearer), and the EPS bearer are also associated. In this case, for example, the logical channel, the RLC entity (and / or RLC bearer) associated with the same DRB identifier (or SRB identifier) ​​in the setting of the source and the setting of the target can be associated with one PDCP entity. In addition, for example, the logical channel, the RLC entity (and / or RLC bearer), and the DRB (or SRB) associated with the same EPS bearer identifier in the setting of the source and the setting of the target can be associated with one PDCP.

[0702] In the above case, the terminal device may regard the PDCP settings of the source and the target associated with one PDCP as being the same. Alternatively, the terminal device may apply the PDCP settings of the target to the PDCP settings of the source.

[0703] In addition, in the case where the source's DRB and the target's DRB (or SRB) having the same DRB identifier are associated with one PDCP entity, the security keys (eg, KUPenc) of the source and the target are different, and thus multiple security keys are managed in one PDCP entity.

[0704] It should be noted that MakeBeforeBreak-r16 may include information indicating which layer of the target is to be generated or not to be generated until the connection to the target is completed.

[0705] It should be noted that, in the case of NR, the (processing E) may include the following processing (E2-1). Fig. 27 As shown, the process (E2-1) may be performed between the process (E-1) and the process (E-2), but the present invention is not limited thereto. In addition, in the case of LTE, the (process LF) may include the processes below the (E2-1) described below. For example, the process (E2-1) may be performed before the process (LF-1), but the present invention is not limited thereto.

[0706] (E2-1) If it is MBB-HO, and a MAC entity for the target (also called a secondary MAC entity) exists as part of the current terminal device's settings, then

[0707] (E2-1-1) Generate a secondary MAC entity.

[0708] As a result, in the process based on the setting of the MAC layer, the MAC entity can be appropriately generated.

[0709] In addition, in the case of NR, the processing within the scope of the processing (B-9) of the (processing B) may be, for example, Fig.28 In addition, in the case of MBB-HO, the setting for "the cell group" in the process after the process (B-9) in the process (B) can be applied to the target.

[0710] (B2-9) If the synchronization re-setting includes information indicating that it is MBB-HO,

[0711] (B2-9-1) If a MAC entity for the target (also called a secondary MAC entity) exists as part of the current terminal device's settings, then

[0712] (B2-9-1-1) The existing MAC entity of the cell group (also called the main MAC entity) is not reset.

[0713] (B2-9-1-2) Generate a secondary MAC entity.

[0714] (B2-9-2) Apply the established (default) MAC cell group settings to the secondary MAC entity. Alternatively, apply the same settings as those of the primary MAC entity to the secondary MAC entity.

[0715] (B2-9-3) Reset the secondary MAC entity.

[0716] (B2-9-4) If set, the SCell of the cell group is considered to be in the deactivated state (Deactivated state).

[0717] (B2-9-5) The value of newUE-Identity is used as the C-RNTI of the cell group.

[0718] In addition, in the case of LTE, the processing within the range of processing (LA-6) to processing (LA-7) in the above-mentioned (processing LA) may be, for example, as follows: Fig.29 Treatment (LA2-6) and treatment (LA2-7) as shown.

[0719] (LA2-6) If makeBeforeBreak-r16 is set, then

[0720] (LA2-6-1) The current terminal device settings (source settings) are copied as the target settings. Unless otherwise specifically stated, the following continued re-setting processing can be performed on the copied target settings. For example, in the case of MBB-HO, the "current terminal device settings" of each process can be regarded as the "target settings of the current terminal device". In addition, for example, the settings to be copied may include (1) bearer settings (such as SRB settings, DRB settings, etc.), (2) cell group settings (such as SpCell settings, SCell settings, RLC entity settings, MAC entity settings, PHY settings, etc.), (3) internal variables (measurement settings (VarMeasConfig), measurement results (VarMeasReportList), timers, counters, etc.), (4) security-related settings (for example, various keys) in part or all. In addition, the SRB settings may not be included in the bearer settings to be copied. That is, with respect to DRB, both the source settings and the target settings can be managed, and with respect to SRB, the settings can be switched from the source settings to the target settings instead of being copied. In addition, information that can determine whether to copy the SRB setting can be included in the RRC connection resetting message including mobilityControlInfo. For example, MakeBeforeBreak-r16 can include the information. In addition, the above-mentioned copying can be accompanied by the generation of entities of each layer (such as RLC entity, MAC entity).

[0721] (LA2-6-2) If a MAC entity for the target (also called a secondary MAC entity) exists as part of the current terminal device's configuration, then

[0722] (LA2-6-2-1) The existing MAC entity of the cell group (also called the main MAC entity) is not reset.

[0723] (LA2-6-2-2) Generate a secondary MAC entity.

[0724] (LA2-6-3) Reset the secondary MAC entity if necessary.

[0725] (LA2-7) Otherwise

[0726] (LA2-7-1) If set, reset MCG's MAC and SCG's MAC.

[0727] As a result, even if the MAC cell group setting is not included in the RRC reconfiguration message of NR, the MAC entity can be properly generated. In addition, even if the MAC main setting is not included in the RRC connection reconfiguration message of EUTRA, the MAC entity can be properly generated.

[0728] In addition, in the (processing I), (processing J) or other processes, when the terminal device receives a message to release the source settings, it can release the current main MAC entity and regard the current secondary MAC entity as the main MAC entity. In addition, when the terminal device receives a message to release the source settings, it can reset the current main MAC entity and not regard the current main MAC entity as the main MAC entity, but regard the current secondary MAC entity as the main MAC entity.

[0729] In this way, the MAC entity can be managed appropriately.

[0730] It should be noted that in the above-mentioned processes, when makeBeforeBreak-r16 is included in the setting of the primary cell group, switching (also called MBB-HO) is performed, and when makeBeforeBreak-r16 is included in the setting of the secondary cell group, change of the secondary cell group (also called MBB-SCG Change) is performed.

[0731] In addition, the terminal device may notify the base station device of part or all of the following information: (1) information indicating whether to support the execution of any one of MBB-HO or MBB-SCG Change that maintains communication using more than two cell groups (e.g., Dual Connectivity, MultiConnectivity); (2) information indicating whether to support the execution of MBB-HO that maintains communication using more than two cell groups (e.g., Dual Connectivity); (3) information indicating whether to support the execution of MBB-SCG Change that maintains communication using more than two cell groups (e.g., Dual Connectivity); (4) information indicating whether to support the execution of both MBB-HO and MBB-SCG Change that maintain Dual Connectivity. For example, the information may be included in a message (e.g., UECapabilityInformation) in which the terminal device notifies the base station device 3 of the capability (Capability) of wireless access. In addition, the information may be notified as information that is independent of the frequency band combination supported by the terminal device. In addition, the information may also be not notified to the base station device.

[0732] In addition, the terminal device may release one or more cell groups other than the MCG to perform MBB-HO. The terminal device may perform the MBB-HO without supporting the execution of the MBB-HO that maintains communications using more than two cell groups. In addition, the terminal device may also release one or more cell groups other than the MCG to perform the MBB-SCG Change. The terminal device may also perform the MBB-SCG Change without supporting the execution of the MBB-SCG Change that maintains communications using more than two cell groups. In addition, the terminal device may perform a normal secondary cell group change (SCG Change) that is not an MBB-SCG Change. The terminal device may perform the secondary cell group change without supporting the execution of the MBB-SCGChange that maintains communications using more than two cell groups. SCG Change may be renamed as synchronous SCG reconfiguration (SCGreconfiguration with sync). In addition, handover (HO) may be renamed as synchronous MCG reconfiguration (MCGreconfiguration with sync).

[0733] Fig.10 Yes means Figure 4 An example of the ASN.1 description of the RRC connection re-establishment message for EUTRA in . Fig.11 Yes means Figure 4 Another example of the ASN.1 description of the RRC connection re-establishment message for EUTRA in . Fig.12 Yes means Figure 4 An example of an ASN.1 description of an RRC reconfiguration message for an NR in . Fig.13 Yes means Figure 4 Another example of the ASN.1 description of the RRC reconfiguration message for NR in.

[0734] exist Fig.10 and Fig.11 The information element indicated by mobilityControlInfo is an information element including parameters related to mobility to EUTRA controlled by the network. The information element indicated by mobilityControlInfo may include part or all of the following information (A) to (H).

[0735] (A) Target physical cell identifier

[0736] (B) t304 indicating information on the time from the start of the timer T304 to its expiration

[0737] (C) newUE-Identity indicating the new identifier (C-RNTI) of UE 122

[0738] (D) Wireless resource settings

[0739] (E) Setting up a dedicated random access channel

[0740] (F) makeBeforeBreak-r14 as a parameter for setting the existing (Release 14) make-before-break switch

[0741] (G) rach-Skip-r14 as a parameter for setting RACH-less switching

[0742] (H) makeBeforeBreak-r16 as a parameter for setting the make-before-break switching of this embodiment

[0743] Fig.10 Indicates that makeBeforeBreak-r16 is an enumeration type example. Fig.11 It indicates that makeBeforeBreak-r16 has the information element MakeBeforeBreak-r16 as a value, and an example in which the information element MakeBeforeBreak-r16 has a plurality of fields.

[0744] exist Fig.12 and Fig.13 In the information element indicated by the synchronization reconfiguration, for example, is an information element including parameters related to the switching of PCell, the addition and change of PSCell. The information element indicated by the synchronization reconfiguration may include part or all of the following information (A) to (F).

[0745] (A) SpCell settings

[0746] (B) t304 indicating information on the time from the start of the timer T304 to its expiration

[0747] (C) newUE-Identity indicating the new identifier (RNTI) of UE 122

[0748] (D) Setting up a dedicated random access channel

[0749] (E) makeBeforeBreak-r16 as a parameter for setting the make-before-break switching of this embodiment

[0750] (F) rach-Skip-r16 as a parameter for setting RACH-less switching

[0751] Fig.12Indicates that makeBeforeBreak-r16 is an enumeration type example. Fig.13 It indicates that makeBeforeBreak-r16 has the information element MakeBeforeBreak-r16 as a value, and an example in which the information element MakeBeforeBreak-r16 has a plurality of fields.

[0752] also, Figure 10 to Figure 13 Some or all of the fields shown may be optional. Figure 10 to Figure 13 The fields shown may be conditionally included in the message.

[0753] It should be noted that whether to apply make-before-break handover (MBB-HO) to each radio bearer can be set from eNB102 or gNB108. When setting whether to apply make-before-break handover to each radio bearer, the parameters related to the make-before-break handover can be set under the radio bearer setting (the information element represented by SRB-ToAddMod and / or the information element represented by DRB-ToAddMod) (lower layer), or can exist under the information element shown by PDCP-Config. In addition, when setting whether to apply make-before-break handover to each radio bearer, the information of the radio bearer to which the make-before-break handover is applied can be made to exist above the radio bearer setting (upper layer), instead of making the parameters related to the make-before-break handover exist under the radio bearer setting or under the information element shown by PDCP-Config.

[0754] Fig. 20 An example of ASN.1 representing parameters (information elements or fields) for setting whether to apply a make-before-break handover (MBB-HO) to a radio bearer to be established or set up according to various embodiments of the present invention is shown in FIG. Fig. 20In the example, an example is shown in which there are parameters under PDCP-Config for setting whether to apply make-before-break switching to the wireless bearer to be established or set, but if it is under the wireless bearer setting, it can exist in any position. It should be noted that the above-mentioned "whether to apply make-before-break switching to the wireless bearer to be established or set" can also be renamed as "whether the wireless bearer to be established or set performs make-before-break switching" and other similar expressions. In addition, the above-mentioned "whether to apply make-before-break switching to the wireless bearer to be established or set" can also be renamed as "whether to apply make-before-break switching to the PDCP entity" or "whether the PDCP entity performs make-before-break switching" or "the PDCP entity has a first setting and a second setting", etc. The above-mentioned first setting can be a source (switching source) setting for the switching. In addition, the above-mentioned second setting can be a target (switching destination) setting for the switching. In addition, the above-mentioned first setting can be a main setting. In addition, the above-mentioned second setting can be a secondary setting. In addition, if the expression means to perform make-before-break switching by setting both the source setting and the target setting and / or the main setting and the auxiliary setting for a PDCP entity, it can be renamed as other expressions.

[0755] exist Fig. 20 In the example, the field expressed by mbb-drb is used as a parameter for "whether to apply make-before-break switching to the radio bearer to be established or set" for explanation, but it can also be a field and / or information element with other names. Fig. 20 (A) shows an example where mbb-drb is an enumeration type. Fig. 20 (B) shows an example in which the MBB-DRB has an information element MBB-DRB as a value, and the information element MBB-DRB has one or more fields. Fig. 20 In (A), it can be shown that when the field represented by mbb-drb is included or is true, a make-before-break switching is applied to the PDCP entity set by PDCP-Config and the radio bearer associated with the PDCP entity. Fig. 20 In (B), the MBB-DRB information element may include, as settings for the switching destination, an identifier of the cell group of the switching destination (a field named targetCellGroupId), a logical channel identifier associated with the PDCP entity at the switching destination (a field named targetLogicalChannelIdentity), and part or all of other parameters (not shown).

[0756] It should be noted that Fig. 20 The fields represented by mbb-drb are shown only in Figures 10 to 13The example shows that the setting has the same parameters as makeBeforeBreak-r16, which is optional. Figures 10 to 13 In the case where the parameter equivalent to makeBeforeBreak-r16 is not set as shown in the example, the field represented by mbb-drb may not exist.

[0757] Fig.21 An example of ASN.1 in which the information of the radio bearer for which make-before-break switching is applied is present on the radio bearer setting is shown in FIG. Fig.21 As shown, Fig.11 and / or Fig.13 One of the parameters of the MakeBeforeBreak-r16 information element (for example, Fig.11 and / or Fig.13 ParameterA or parameterB) shown in FIG. 1 may contain information about the radio bearer to which make-before-break switching is applied. Fig.21 In the example of , as the parameter of "information of radio bearers to which make-before-break switching is applied", fields represented by mbb-drb and mbb-drbList (list of mbb-drb) are used for explanation, but fields and / or information elements with other names may also be used. Fig.21 As shown, the information of the radio bearer for the make-before-break switching application may include a radio bearer identifier of the radio bearer for the make-before-break switching application (a field represented by drb-Identity), an identifier of the cell group of the switching destination (a field named targetCellGroupId), a logical channel identifier associated with the PDCP entity at the switching destination (a field named targetLogicalChannelIdentity), and part or all of other parameters (not shown). Fig.21 In the example of , in the absence of the parameter "information of radio bearers to which make-before-break switching is applied", make-before-break switching can be applied to all radio bearers or all data radio bearers. Fig.21 The “information of radio bearers for make-before-break switching” only shows the information of data radio bearers (DRBs), but may also include the information of signaling radio bearers (SRBs).

[0758] Figure 5 It is a block diagram showing the configuration of a terminal device (UE122) according to each embodiment of the present invention. Figure 5 Only the main components closely related to one embodiment of the present invention are shown.

[0759] Figure 5The UE 122 shown in the figure is composed of a receiving unit 500 that receives an RRC message from a base station device, a processing unit 502 that processes the setting information according to any or all of the various information elements (IE: Information Element), various fields, and various conditions included in the received message, and a sending unit 504 that sends an RRC message to the base station device. The above-mentioned base station device sometimes refers to eNB 102 and sometimes refers to gNB 108. In addition, the processing unit 502 may include part or all of the functions of various layers (such as the physical layer, MAC layer, RLC layer, PDCP layer, RRC layer, and NAS layer). That is, the processing unit 502 may include part or all of the physical layer processing unit, the MAC layer processing unit, the RLC layer processing unit, the PDCP layer processing unit, the RRC layer processing unit, and the NAS layer processing unit.

[0760] Figure 6 is a block diagram showing the configuration of a base station device according to each embodiment of the present invention. Figure 6 Only the main components closely related to one scheme of the present invention are shown. The above-mentioned base station device sometimes refers to eNB102 and sometimes refers to gNB108.

[0761] Figure 6 The base station device shown in the figure is configured to include: a sending unit 600, which sends an RRC message to UE122; a processing unit 602, which prepares an RRC message including any or all of the setting information of various information elements (IE: Information Element), various fields, and various conditions, and sends it to UE122, so that the processing unit 502 of UE122 processes it; and a receiving unit 604, which receives the RRC message from UE122. In addition, the processing unit 602 may include part or all of the functions of various layers (such as the physical layer, MAC layer, RLC layer, PDCP layer, RRC layer, and NAS layer). That is, the processing unit 602 may include part or all of the physical layer processing unit, the MAC layer processing unit, the RLC layer processing unit, the PDCP layer processing unit, the RRC layer processing unit, and the NAS layer processing unit.

[0762] Fig. 22 1 is a block diagram showing the configuration of the protocol established and / or set in the UE 122 according to various embodiments of the present invention. Fig. 22 Only the main components closely related to one embodiment of the present invention are shown. Fig. 22PDCP entity 2200, RLC entity 2202 and RLC entity 2204 are established and / or set in UE112 shown in the figure. It should be noted that PDCP entity 2200, RLC entity 2202 and RLC entity 2204 do not always exist, and may exist only when the RRC layer as the upper layer is established and / or set. In addition, RLC entity 2202 and / or RLC entity 2204 are not limited to one RLC entity, and may be multiple RLC entities. It should be noted that the PDCP entity may be renamed as PDCP layer, or may be renamed as PDCP. One or more PDCP sub-entities for performing part of the functions of PDCP may exist in PDCP entity 2202. In addition, the RLC entity may be renamed as RLC layer, or may be renamed as RLC. In addition, RLC entity 2202 may be part of a first RLC bearer, and RLC2204 may be part of a second RLC bearer different from the first RLC bearer. In various embodiments of the present invention, the RLC entity 2202 and the RLC entity 2204 may be respectively renamed as RLC bearer 2202 and RLC bearer 2204. In addition, the RLC entity 2202 may be associated with a first cell group, and the RLC 2204 may be associated with a second cell group different from the first cell group. In various embodiments of the present invention, the RLC entity 2202 and the RLC entity 2204 may be respectively renamed as cell group 2202 and cell group 2204. In addition, a first MAC entity may exist in the first cell group, and a second MAC entity different from the first MAC entity may exist in the second cell group.

[0763] Next, use Figure 4 ,as well as Figure 22 to Figure 26 , the processing of the protocol in UE122 of an embodiment of the present invention is explained.

[0764] exist Figure 4In the process, the RRC layer of eNB102 or gNB108 makes a message for resetting the RRC connection (connection) (step S400) and sends it to the RRC layer of UE122 (step S402). When the message for resetting the RRC connection (connection) includes parameters associated with PDCP, the RRC layer of UE122 establishes a PDCP entity, sets up the PDCP entity, requests the PDCP entity, provides the ciphering algorithm and ciphering key to the PDCP entity, and provides the integrity protection algorithm and integrity protection key to the PDCP entity according to the parameters associated with the above PDCP. In addition to the PDCP settings (PDCP-Config), the parameters associated with the above PDCP may be parameters related to the re-establishment of PDCP, the recovery of PDCP, security, etc. If the message for resetting the above RRC connection does not include the application of make-before-break handover (MBB-HO), the RRC layer of UE122 may perform MBB-HO-related settings on the PDCP entity associated with the radio bearer to which MBB-HO is applied (step S404).

[0765] In addition, in step S404, the RRC layer of UE122 performs the setting of the cell group according to the parameters associated with the setting of the cell group, when the message for resetting the RRC connection (connection) includes parameters associated with the setting of the cell group. For example, when the parameters associated with the setting of the above-mentioned cell group include parameters related to the RLC setting or the RLC bearer, the RLC entity is established and / or set. In the case where the logical channel identifier associated with the above-mentioned RLC setting is not set in the above-mentioned cell group, the above-mentioned RLC entity can be established. In addition, when the RLC entity is established, the RRC layer of UE122 can associate any one or all of the RLC entity, RLC bearer and logical channel with the PDCP entity based on the radio bearer identifier associated with the above-mentioned RLC setting or RLC bearer setting. When the RRC layer of UE122 associates any one or all of the above-mentioned RLC entity, RLC bearer and logical channel with the PDCP entity, it can establish an association with the PDCP entity associated with the same radio bearer identifier. In addition, the RRC layer of UE122 may associate any or all of the above RLC entities, RLC bearers, and logical channels with sub-entities of the PDCP entity. In the case where there are multiple sub-entities of the PDCP entity, information related to the associated sub-entities may be included in the message for resetting the above RRC connection.

[0766] Fig.23This is an example of a processing method of the PDCP entity 2200 in various forms of the present embodiment. As a first RLC entity, the RLC entity 2202 may be associated with the PDCP entity 2200 or a first sub-entity (not shown) of the PDCP entity 2200. The PDCP entity 2200 may associate a portion or all of the encryption algorithm and encryption key provided by the RRC layer as an upper layer, the integrity protection algorithm and integrity protection key provided by the RRC layer as an upper layer, the state of header compression (RoHC), and other information with the RLC entity 2202. In addition, a portion or all of the encryption algorithm and encryption key associated with the RLC entity 2202, the integrity protection algorithm and integrity protection key provided by the RRC layer as an upper layer, the state of header compression (RoHC), and other information may be applied as the first information, namely, the first encryption algorithm and the first encryption key, the first integrity protection algorithm and the first integrity protection key, and the state of the first header compression (RoHC) (step S2300).

[0767] Next, the PDCP entity 2200 or the second sub-entity of the PDCP entity 2200 may perform part or all of the following processing (A) to (G) based on the first request made by the RRC layer as the upper layer. It should be noted that the second sub-entity of the above-mentioned PDCP entity 2200 may be established and / or set based on the first request made by the RRC layer as the upper layer.

[0768] (Step S2302)

[0769] (A) The RLC entity 2204 associated with the PDCP entity 2200 is regarded as a second RLC entity and / or a second sub-entity of the PDCP entity 2200 is associated with the RLC entity 2204.

[0770] (B) The information associated with the RLC entity 2202 in step S2300 (part or all of the encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, RoHC status, and other information) is saved as the first information, i.e., part or all of the first encryption algorithm, the first encryption key, the first integrity assurance algorithm, the first integrity assurance key, and the first RoHC status.

[0771] (C) The encryption algorithm and encryption key provided from the upper layer are applied and / or associated with the RLC entity 2204 as the second encryption algorithm and the second encryption key.

[0772] (D) The integrity protection algorithm and integrity protection key provided from the upper layer are applied and / or associated with the RLC entity 2204 as the second integrity protection algorithm and the second integrity protection key.

[0773] (E) For downlink reception from the RLC entity 2204, as the second RoHC state, the header compression protocol is started in the NC (No Context) state of the single direction mode (U-mode).

[0774] (F) is used to send to the uplink of the RLC entity 2204, as the second RoHC state, to start the header compression protocol in the IR (Initialization and Refresh) state of the single direction mode (U-mode).

[0775] (G) Other processing.

[0776] It should be noted that the processing of (E) and / or (F) in step S2302 can be performed only when the continuation of the header compression protocol is not set by the RRC layer as the upper layer. In addition, in the case where the continuation of the header compression protocol is set by the RRC layer as the upper layer, in step S2302, the first RoHC state for the above-mentioned downlink reception and the first RoHC state for the above-mentioned uplink transmission can be copied to the second RoHC state for downlink reception and the second RoHC state for uplink transmission, respectively, or the RoHC state may not be divided into the first RoHC state and the second RoHC state, but may be used as a common RoHC state. It should be noted that even in the case where the continuation of the header compression protocol is not set by the RRC layer as the upper layer, the RoHC state may not be divided into the first RoHC state and the second RoHC state, but may be used as a common RoHC state. In addition, based on the above-mentioned first request, the RoHC state may not be divided into the first RoHC state and the second RoHC state, but may be used as a common RoHC state. Next, in step S2302, when the RoHC state is not divided into the first RoHC state and the second RoHC state but has a common RoHC state, the first RoHC state and the second RoHC state may be renamed as the common RoHC state in the subsequent step S2400 and the subsequent step S2500.

[0777] In step S2302, the first request may be a request for MBB-HO or a request for re-establishment of the PDCP entity. In addition, in step 2302, when the first request is received from the upper layer, the PDCP entity 2200 may further perform part or all of the processing of (A) to (G) in the above step S2302 on the PDCP entity 2200 that has received the above first request or the radio bearer associated with the PDCP entity 2200 that has received the above first request based on the first setting. The above first setting may be a setting related to MBB-HO performed by the RRC layer as the upper layer. The setting related to the above MBB-HO may be the application of MBB-HO or a setting related to part or all of the second RLC entity, the second RLC bearer, the second logical channel, and the second cell group.

[0778] In addition, in step 2302, when the first request is received from the upper layer, the PDCP entity 2200 may further perform part or all of the subsequent (H) to (S) on the PDCP entity 2200 that has received the above-mentioned first request or the wireless bearer associated with the PDCP entity 2200 that has received the above-mentioned first request based on the fact that the above-mentioned first setting has not been performed.

[0779] (H) For downlink reception from the RLC entity 2204, the header compression protocol is reset and the header compression protocol is started in the NC (No Context) state of the single direction mode (U-mode). This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0780] (I) Reset the header compression protocol for uplink transmission to the RLC entity 2204, and start the header compression protocol in the IR (Initialization and Refresh) state of the single direction mode (U-mode). This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0781] (J) On the transmitting side, for the UM DRB, TX_NEXT (a variable indicating a COUNT value or a sequence number allocated to the next PDCP SDU when the next PDCP SDU is transmitted) is set to an initial value.

[0782] (K) In processing the first request, the encryption algorithm and encryption key provided from the upper layer are applied.

[0783] (L) In the processing of the first request, the integrity protection algorithm and integrity protection key provided from the upper layer are applied.

[0784] (M) On the transmitting side, although a sequence number is allocated in the PDCP SDU for the UM DRB, the PDCP SDU is not transmitted to the lower layer as a PDCP PDU, but the PDCP SDU is received from the upper layer and transmitted in the order of the COUNT value allocated before the first request processing is performed. At this time, the timer for deleting the transmitted PDCP SDU may not be restarted.

[0785] (N) On the transmitting side, for the AM DRB, the PDCP SDUs that are not confirmed to be successfully transmitted from the lower layer are transmitted or retransmitted in the order of the COUNT values ​​assigned before the first request is processed. At this time, header compression can be performed. In addition, at this time, the assigned COUNT value can be used for encryption and / or integrity protection.

[0786] (O) On the receiving side, the PDCP DATA PDU received from the lower layer is processed by the first requested process.

[0787] (P) On the receiving side, for UM DRBs, the stored PDCP SDUs are delivered to the upper layer in the order of COUNT values. At this time, header restoration can be performed. In addition, this processing can be performed when the reordering timer is running or when reordering is set. When the above-mentioned reordering timer is running, the above-mentioned reordering timer can be stopped and reset.

[0788] (Q) On the receiving side, for the AM DRB, headers of all stored PDCP PDUs are restored. This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0789] (R) On the receiving side, for the UM DRB, RX_NEXT (a variable indicating the COUNT value of the PDCP SDU expected to be received next) and / or RX_DELIV (a variable indicating the COUNT value of the first PDCP SDU to be received but not delivered to the upper layer) are set to initial values.

[0790] (S) Other processing.

[0791] In addition, in step 2302, when the above-mentioned first request is received from the upper layer, the first sub-entity of the PDCP entity 2200 and / or the second sub-entity of the PDCP entity 2200 may perform part or all of the following (H) to (S).

[0792] (H) For downlink reception, the header compression protocol is started in the NC (No Context) state of the single direction mode (U-mode). This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0793] (I) For uplink transmission, the header compression protocol is started in the IR (Initialization and Refresh) state of the unidirectional mode (U-mode). This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0794] (J) On the transmitting side, for the UM DRB, TX_NEXT (a variable indicating a COUNT value or a sequence number allocated to the next PDCP SDU when the next PDCP SDU is transmitted) is set to an initial value.

[0795] (K) In processing the first request, the encryption algorithm and encryption key provided from the upper layer are applied.

[0796] (L) In the processing of the first request, the integrity protection algorithm and integrity protection key provided from the upper layer are applied.

[0797] (M) On the transmitting side, although a sequence number is allocated in the PDCP SDU for the UM DRB, the PDCP SDU is not transmitted to the lower layer as a PDCP PDU, but is received from the upper layer and transmitted in the order of the COUNT value allocated before the first request is processed. At this time, the timer for deleting the transmitted PDCP SDU may not be restarted.

[0798] (N) On the transmitting side, for the AM DRB, the PDCP SDUs that are not confirmed to be successfully transmitted from the lower layer are transmitted or retransmitted in the order of the COUNT values ​​assigned before the first request is processed. At this time, header compression can be performed. In addition, at this time, the assigned COUNT value can be used for encryption and / or integrity protection.

[0799] (O) On the receiving side, the PDCP DATA PDU received from the lower layer is processed by the first requested process.

[0800] (P) On the receiving side, for UM DRBs, the stored PDCP SDUs are delivered to the upper layer in the order of COUNT values. At this time, header restoration can be performed. In addition, this processing can be performed when the reordering timer is running or when reordering is set. When the above-mentioned reordering timer is running, the above-mentioned reordering timer can be stopped and reset.

[0801] (Q) On the receiving side, for the AM DRB, headers of all stored PDCP PDUs are restored. This process can be performed without setting the continuation of the header compression protocol by the RRC layer as the upper layer.

[0802] (R) On the receiving side, for the UM DRB, RX_NEXT (a variable indicating the COUNT value of the PDCP SDU expected to be received next) and / or RX_DELIV (a variable indicating the COUNT value of the first PDCP SDU to be received but not delivered to the upper layer) are set to initial values.

[0803] (S) Other processing.

[0804] It should be noted that these processes can be performed based on the above-mentioned first setting.

[0805] In addition, in step S2302, the first sub-entity, the first RLC entity, the first information (the first encryption algorithm and the first encryption key, the first integrity protection algorithm and the first integrity protection key, the first RoHC state, the first other information) may be the sub-entity, RLC entity, and information for the switching source (source) of MBB-HO and / or for the cell group of the switching source and / or the primary. In addition, in step S2302, the second sub-entity, the second RLC entity, the second information (the second encryption algorithm and the second encryption key, the second integrity protection algorithm and the second integrity protection key, the second RoHC state, the second other information) may be the sub-entity, RLC entity, and information for the switching destination (target) of MBB-HO and / or for the cell group of the switching destination and / or the secondary.

[0806] Furthermore, part or all of the processing in (A) to (G) in step S2302 may be performed without being based on the first request from the RRC layer as an upper layer.

[0807] Fig.24 This is an example of a downlink reception processing method of each form of the PDCP entity 2200 of this embodiment. It should be noted that the step S2400 described later can be performed based on performing a part or all of the steps in the above steps S2300 and S2302, or after performing a part or all of the steps in the above steps S2300 and S2302.

[0808] In addition, the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 in the step S2400 described later may be the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first RLC entity and the second RLC entity in the step S2400 described later may be the first RLC and the second RLC entity respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key in the step S2400 described later may be the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key in step S2400 described later may be the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first RoHC state and the second RoHC state in step S2400 described later may be the first RoHC state and the second RoHC state respectively shown in part or all of the above-mentioned steps S2300 and S2302.

[0809] When the PDCP entity 2200 receives the PDCP DATA PDU from the first RLC entity, the first sub-entity of the PDCP entity 2200 may perform some or all of the following (A) to (C) and (G). When the PDCP entity 2200 receives the PDCP DATA PDU from the second RLC entity, the second sub-entity of the PDCP entity 2200 may perform some or all of the following (D) to (G). (Step S2400)

[0810] (A) Decoding is performed using the first encryption algorithm, the first encryption key, and a COUNT value obtained from a header of a PDCP DATA PDU received from the first RLC entity.

[0811] (B) Performing integrity verification using the first integrity protection algorithm, the first integrity protection key, and a COUNT value obtained from a header of the PDCP DATA PDU received from the first RLC entity.

[0812] (C) Header restoration is performed using the first RoHC state described above.

[0813] (D) Decoding is performed using the second encryption algorithm, the second encryption key, and a COUNT value obtained from a header of the PDCP DATA PDU received from the second RLC entity.

[0814] (E) Performing integrity verification using the second integrity protection algorithm, the second integrity protection key, and a COUNT value obtained from a header of the PDCP DATA PDU received from the second RLC entity.

[0815] (F) Header restoration is performed using the second RoHC state described above.

[0816] (G) Other processing.

[0817] It should be noted that (G) other processing may include or exclude some or all of the following situations: "using the receiving window value to determine the COUNT value", "discarding the PDCP Data PDU when the determined COUNT value is less than the COUNT value of the first PDCP SDU that has not yet been delivered to the upper layer or when a PDCP Data PDU with the same COUNT value as the determined COUNT value has been received"; and "in the case of integrity verification failure, notifying the upper layer of the integrity verification failure".

[0818] In step S2400, re-ordering may be performed before or after header restoration is performed through (C) or (F), or both before and after header restoration is performed. Re-ordering may be a process for storing the PDCP SDU in a receiving buffer and handing over the PDCP SDU to an upper layer in the order of COUNT values ​​obtained according to header information of the PDCP DATA PDU. In addition, re-ordering may be a process including delivering the stored PDCP SDU to an upper layer in the order of COUNT values ​​when the COUNT value of the received PDCP Data PDU is the COUNT value of the first PDCP SDU that has not been delivered to the upper layer. In addition, the above-mentioned re-ordering may be performed in a re-ordering sub-entity (not shown) of the PDCP entity 2200. The COUNT value of the PDCP SDU may be transferred from the first sub-entity of the PDCP entity 2200 and / or the second sub-entity of the PDCP entity 2200 to the re-ordering sub-entity of the PDCP entity 2200 together with the PDCP SDU after header restoration.

[0819] In addition, in step S2400, the first sub-entity of the PDCP entity 2200 and / or the second sub-entity of the PDCP entity 2200 may perform part or all of the following processing (H) to (M) based on the settings of each sub-entity.

[0820] (H) Use the receive window value to determine the COUNT value.

[0821] (I) Decoding is performed using the determined COUNT value.

[0822] (J) Use the determined COUNT value to perform integrity verification. If the integrity verification fails, notify the upper layer of the integrity verification failure.

[0823] (K) In a case where the determined COUNT value is less than the COUNT value of the first PDCP SDU that has not yet been delivered to the upper layer or in a case where a PDCP Data PDU having the same COUNT value as the determined COUNT value has been received, discarding the PDCP Data PDU.

[0824] (L) When reordering is performed and header restoration is not performed, header restoration is performed and the PDCP SDU is delivered to the upper layer.

[0825] (M) Other treatments.

[0826] It should be noted that the processing of step S2400 can be performed on the above-mentioned PDCP entity 2200 or the radio bearer associated with the above-mentioned PDCP entity 2200 based on the first setting. The above-mentioned first setting may be the first setting in the above-mentioned step S2302. That is, the setting related to MBB-HO may be performed by the RRC layer as the upper layer. The setting related to the above-mentioned MBB-HO may be the application of MBB-HO, or it may be a setting related to part or all of the second RLC entity, the second RLC bearer, the second logical channel, and the second cell group. In addition, it may also be necessary to set out of order delivery when the above-mentioned first setting is performed on the above-mentioned PDCP entity 2200 or the radio bearer associated with the above-mentioned PDCP entity 2200. Setting out of order delivery may include setting in MBB-HO that no reordering is performed before header recovery.

[0827] In addition, in step S2400, the first sub-entity, the first RLC entity, the first encryption algorithm and the first encryption key, the first integrity protection algorithm and the first integrity protection key, and the first RoHC state may be a sub-entity, RLC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state for a switching source (source) of MBB-HO and / or for a cell group of the switching source and / or a primary. In addition, in step S2400, the second sub-entity, the second RLC entity, the second encryption algorithm and the second encryption key, the second integrity protection algorithm and the second integrity protection key, and the second RoHC state may be a sub-entity, RLC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state for a switching destination (target) of MBB-HO and / or for a cell group of the switching destination and / or a secondary.

[0828] Fig.25 This is an example of the uplink transmission processing method of each form of the DCP entity 2200 of this embodiment. It should be noted that the step S2500 described later can be performed based on the above steps S2300 and S2302, or after the above steps S2300 and S2302, or after the above steps S2300 and S2302, are performed.

[0829] In addition, the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 in the step S2500 described later may be the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first RLC entity and the second RLC entity in the step S2500 described later may be the first RLC and the second RLC entity respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key in the step S2500 described later may be the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key in step S2500 described later may be the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first RoHC state and the second RoHC state in step S2500 described later may be the first RoHC state and the second RoHC state respectively shown in part or all of the above-mentioned steps S2300 and S2302.

[0830] The PDCP entity 2200 or the first sub-entity of the PDCP entity 2200 may perform part or all of the following (A) to (D) and (I) on the PDCP SDU received from the upper layer when the second request is not detected. In addition, the PDCP entity 2200 or the second sub-entity of the PDCP entity 2200 may perform part or all of the following (E) to (I) on the PDCP SDU received from the upper layer based on the detection of the second request.

[0831] (Step S2500)

[0832] (A) Header compression is performed using the first header compression process described above.

[0833] (B) Encryption is performed using the first encryption algorithm, the first encryption key, and the COUNT value associated with the PDCP SDU.

[0834] (C) Performing integrity protection using the first integrity protection algorithm, the first integrity protection key, and the COUNT value associated with the PDCP SDU.

[0835] (D) Delivering the prepared PDCP PDU to the above-mentioned first RLC entity.

[0836] (E) Perform header compression using the second header compression process described above.

[0837] (F) Encryption is performed using the second encryption algorithm, the second encryption key, and the COUNT value associated with the PDCP SDU.

[0838] (G) Performing integrity protection using the second integrity protection algorithm, the second integrity protection key, and the COUNT value associated with the PDCP SDU.

[0839] (H) Delivering the prepared PDCP PDU to the above-mentioned second RLC entity.

[0840] (I) Other treatments.

[0841] It should be noted that, when there are multiple associated RLC entities in (D) and / or (H) of the PDCP entity 2200 or the first sub-entity of the PDCP entity 2200 or the second sub-entity of the PDCP entity 2200, part or all of the processing in (D-1)(H-1) and (D-2)(H-2) can be further performed.

[0842] (D-1)(H-1) When PDCP duplication is activated, in the case of PDCP Data PDU, duplication is performed and provided to the two associated RLC entities, and in the case of PDCP Control PDU, it is provided to the master RLC entity.

[0843] (D-2)(H-2) When PDCP replication is not activated, if two associated RLC entities belong to different cell groups, if the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is above the threshold of uplink data, the PDCP PDU is provided to the primary RLC entity or the secondary RLC entity. In all other cases (the two associated RLC entities belong to different or the same cell groups and / or the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is less than the threshold of uplink data), the PDCP PDU is provided to the primary RLC entity.

[0844] In addition, in step S2500, the PDCP entity 2200 or the first sub-entity of the PDCP entity 2200 may, based on the fact that the second request is not detected, perform part or all of the following (J) to (R) processing on the PDCP SDU received from the upper layer based on the first information that has been set. In addition, in step S2500, the PDCP entity 2200 or the second sub-entity of the PDCP entity 2200 may, based on the fact that the second request is not detected, perform part or all of the following (J) to (R) processing on the PDCP SDU received from the upper layer based on the second information that has been set.

[0845] (J) If a discard timer is set, the discard timer is started.

[0846] (K) Associating a COUNT value corresponding to TX_NEXT (a variable representing a COUNT value or sequence number assigned to a PDCP SDU when transmitting the next PDCP SDU) with the received PDCP SDU.

[0847] (L) Perform header compression.

[0848] (M) Use TX_NEXT to perform encryption.

[0849] (N) Use TX_NEXT for integrity protection.

[0850] (O) Calculate and set the sequence number based on TX_NEXT.

[0851] (P) Increase (increment) TX_NEXT by 1.

[0852] (Q) The prepared PDCP Data PDU is provided to the lower layer in the following manner.

[0853] (Q-1) When there is an RLC entity associated with the sub-entity, the PDCP PDU is provided to the associated RLC entity.

[0854] (Q-2) In the case where there are two RLC entities for a sub-entity association:

[0855] (Q-2-1) When PDCP duplication is activated, in the case of PDCP Data PDU, duplication is performed and provided to the two associated RLC entities, and in the case of PDCP Control PDU, it is provided to the master RLC entity.

[0856] (Q-2-2) When PDCP replication is not activated, if two associated RLC entities belong to different cell groups, if the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is above the threshold of uplink data, the PDCP PDU is provided to the primary RLC entity or the secondary RLC entity. In all other cases (the two associated RLC entities belong to different or the same cell groups and / or the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is less than the threshold of uplink data), the PDCP PDU is provided to the primary RLC entity.

[0857] (R) Other processing.

[0858] In the above step S2500, the detection method of the second request may be a method of detecting by receiving the second request from an upper layer or a lower layer. In addition, in the above step S2500, the detection method of the second request may be a method of detecting by cutting off a timer set for detecting the second request in the PDCP entity 2200. In addition, in the above step S2500, the detection method of the second request may also be a method of detecting by installing a terminal device.

[0859] It should be noted that, in the above-mentioned step S2500, the second request may be a request for switching the providing destination of the PDCP PDU from the above-mentioned first RLC entity to the above-mentioned second RLC entity in the sending process, or may be a request for performing MBB-HO. In addition, if the above-mentioned second request indicates a request for switching the providing destination of the PDCP PDU from the above-mentioned first RLC entity to the above-mentioned second RLC entity in the sending process when performing MBB-HO, it may also be other names.

[0860] It should be noted that the processing of (F) in the above step S2302 may be performed after the above second request is detected or immediately before the above second request is detected.

[0861] It should be noted that the processing of step S2500 can be performed based on the first setting of the above-mentioned PDCP entity 2200 or the radio bearer associated with the above-mentioned PDCP entity 2200. The above-mentioned first setting may be the first setting in the above-mentioned step S2302. That is, the setting related to MBB-HO may be performed by the RRC layer as the upper layer. The setting related to the above-mentioned MBB-HO may be the application of MBB-HO, or it may be a setting related to part or all of the second RLC entity, the second RLC bearer, the second logical channel, and the second cell group. In addition, the processing of step S2500 may also be further performed based on the situation where two or more RLC entities are associated with the PDCP entity 2200.

[0862] In addition, when the PDCP entity 2200 is associated with two or more RLC entities, without performing the above-mentioned first setting, the PDCP entity 2200 may perform part or all of the following processing (S) to (U).

[0863] (S) When PDCP duplication is activated, in the case of PDCP Data PDU, duplication is performed and provided to the two associated RLC entities, and in the case of PDCP Control PDU, it is provided to the master RLC entity.

[0864] (T) In the case where PDCP replication is not activated, if two associated RLC entities belong to different cell groups, if the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is above the threshold for uplink data, the PDCP PDU is provided to the primary RLC entity or the secondary RLC entity. In all other cases (the two associated RLC entities belong to different or the same cell groups and / or the total amount of the PDCP data volume pending for initial transmission and the RLC data volume of the two associated RLC entities is less than the threshold for uplink data), the PDCP PDU is provided to the primary RLC entity.

[0865] (U) Other treatments.

[0866] In addition, in step S2500, the first sub-entity, the first RLC entity, the first encryption algorithm and the first encryption key, the first integrity protection algorithm and the first integrity protection key, and the first RoHC state may be a sub-entity, RLC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state for a switching source (source) of MBB-HO and / or for a cell group of the switching source and / or a primary. In addition, in step S2500, the second sub-entity, the second RLC entity, the second encryption algorithm and the second encryption key, the second integrity protection algorithm and the second integrity protection key, and the second RoHC state may be a sub-entity, RLC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state for a switching destination (target) of MBB-HO and / or for a cell group of the switching destination and / or a secondary.

[0867] In addition, the MAC entity of the above-mentioned second cell group in which the above-mentioned second RLC entity is set can send a first notification to the upper layer after receiving the first uplink authorization from the base station device. The first notification can be a notification related to the acceptance of the first uplink authorization, or it can be a notification indicating that the uplink transmission is switched to a part or all of the second RLC entity, the second RLC bearer, the second logical channel and the second cell group. It should be noted that after the MAC entity receives the first uplink authorization from the base station device, the processing of sending the first notification to the upper layer can be performed based on the setting of MBB-HO.

[0868] Fig.26 It is another example of the processing method of the PDCP entity 2200 of each form of this embodiment. It should be noted that the following step S2600 can be performed based on or after performing a part or all of the steps S2300 and S2302.

[0869] In addition, the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 in the step S2600 described later may be the PDCP entity 2200, the first sub-entity of the PDCP entity 2200, and the second sub-entity of the PDCP entity 2200 respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first RLC entity and the second RLC entity in the step S2600 described later may be the first RLC entity and the second RLC entity respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key in the step S2600 described later may be the first encryption algorithm, the first encryption key, the second encryption algorithm, and the second encryption key respectively shown in part or all of the above-mentioned steps S2300 and S2302. In addition, the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key in the later-described step S2600 may be the first integrity protection algorithm, the first integrity protection key, the second integrity protection algorithm, and the second integrity protection key respectively shown in part or all of the above-described steps S2300 and step S2302. In addition, the first RoHC state and the second RoHC state in the later-described step S2600 may be the first RoHC state and the second RoHC state respectively shown in part or all of the above-described steps S2300 and step S2302. In addition, the first setting in the later-described step S2600 may be the first setting in the above-described step S2302.

[0870] When the PDCP entity 2200 detects the third request, it may perform part or all of the following (A) to (K). (Step S2600)

[0871] (A) The second RLC entity mentioned above is regarded as the first RLC entity.

[0872] (B) The second radio bearer associated with the second RLC entity is regarded as the first radio bearer.

[0873] (C) The second RLC bearer associated with the second RLC entity is regarded as the first RLC bearer.

[0874] (D) The second cell group associated with the above-mentioned second RLC entity is regarded as the first cell group.

[0875] (E) The second MAC entity associated with the above-mentioned second RLC entity is regarded as the first MAC entity.

[0876] (F) The above-mentioned second encryption algorithm and the above-mentioned second encryption key are respectively referred to as the first encryption algorithm and the first encryption key.

[0877] (G) The second integrity protection algorithm and the second integrity protection key are regarded as the first integrity protection algorithm and the first integrity protection key respectively.

[0878] (H) The above-mentioned second RoHC state is regarded as the first RoHC state.

[0879] (I) Erase the above-mentioned first setting.

[0880] (J) The second sub-entity of the above-mentioned PDCP entity 2200 is regarded as the first sub-entity of the PDCP entity 2200.

[0881] (K) Other processing.

[0882] The detection of the third request in the above-mentioned step S2600 may be the release and / or stop of the first RLC entity in the above-mentioned step S2300 and / or step S2302. In addition, the detection of the third request in the above-mentioned step S2600 may be the detection of the second request in the above-mentioned step S2500. In addition, the detection of the third request in the above-mentioned step S2600 may be a method of detecting by cutting off the timer set for detecting the third request in the PDCP entity 2200. In addition, the detection of the third request in the above-mentioned step S2600 may be a method of detecting by accepting the third request from the upper layer or the lower layer. In addition, in the above-mentioned step S2600, the detection method of the second request may also be a method of detecting by installing a terminal device.

[0883] In addition, in step S2600, the first sub-entity, the first RLC entity, the first radio bearer, the first RLC bearer, the first cell group, the first MAC entity, the first encryption algorithm and the first encryption key, the first integrity protection algorithm and the first integrity protection key, and the first RoHC state may be a handover source (source) for MBB-HO and / or a cell group for the handover source and / or a primary sub-entity, RLC entity, radio bearer, RLC bearer, cell group, MAC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state. In addition, in step S2600, the second sub-entity, the second RLC entity, the second radio bearer, the second RLC bearer, the second cell group, the second MAC entity, the second encryption algorithm and the second encryption key, the second integrity protection algorithm and the second integrity protection key, and the second RoHC state may be a handover destination (target) for MBB-HO and / or a cell group for the handover destination and / or a secondary sub-entity, RLC entity, radio bearer, RLC bearer, cell group, MAC entity, encryption algorithm and encryption key, integrity protection algorithm and integrity protection key, and RoHC state.

[0884] As described above, in the embodiment of the present invention, efficient communication can be performed when UE 122 is switched.

[0885] In the above description, the expressions "associate", "establish correspondence", "establish association" and the like can be interchanged.

[0886] In the above description, "in the case of MBB-HO" may be a case where, when RRC connection reconfiguration including MobilityControlInfo is performed in LTE or when RRC reconfiguration including synchronization reconfiguration is performed in NR, transmission and / or reception in the target cell is performed while transmission and / or reception of user data in the source cell is continued, and may also be expressed by other names representing equivalent actions. In addition, "in the case of MBB-HO" may also be a case where, in LTE or in NR, a specific information element (such as Figure 10 to Figure 13 , Fig.21 The MakeBeforeBreak-r16 information element shown in and / or Figure 20 to Figure 22 In addition, "in the case of MBB-HO" may also mean that the time (interruption time) during which data communication between the terminal device and the base station device cannot be performed is set to zero milliseconds (0msec) or close to zero milliseconds, and may also be expressed by other names representing it.

[0887] In addition, in the above description, the "MBB-HO-related settings" may be settings for performing transmission and / or reception in the target cell while continuing to transmit and / or receive user data in the source cell when performing RRC connection reconfiguration including MobilityControlInfo in LTE or performing RRC reconfiguration including synchronization reconfiguration in NR, and may also be expressed by other names representing equivalent settings. In addition, the "MBB-HO-related settings" may also be specific information elements (such as Figure 10 to Figure 13 , Fig.21 The MakeBeforeBreak-r16 information element shown in and / or Figure 20-21 In addition, "in the case of MBB-HO" may also mean that the time (interruption time) during which data communication between the terminal device and the base station device cannot be performed is set to zero milliseconds (0msec) or close to zero milliseconds, and may also be expressed by other names representing it.

[0888] In addition, in the above description, "applying make-before-break handover (MBB-HO)" may be applied when performing RRC connection reconfiguration including MobilityControlInfo in LTE or when performing RRC reconfiguration including synchronous reconfiguration in NR, while continuing to send and / or receive user data in the source cell, and may also be expressed by other names indicating equivalent processing. In addition, "applying MBB-HO" may be in LTE or NR, a specific information element (such as Figure 10 to Figure 13 , Fig.21 The MakeBeforeBreak-r16 information element shown in and / or Figure 20-21 In addition, "applying MBB-HO" may also be a process of setting the time (interruption time) during which data communication between the terminal device and the base station device cannot be performed to zero milliseconds (0msec) or close to zero milliseconds, and may also be expressed by other names representing the same.

[0889] It should be noted that, in various embodiments of the present invention, the switching may be renamed as Reconfiguration With Sync. For example, the Make-Before-Break switching may be renamed as Make-Before-Break Synchronous Reconfiguration.

[0890] It should be noted that, in the above description, “A may be renamed as B” includes the meaning of changing B to A in addition to changing A to B.

[0891] It should be noted that in the above description, the main sub-entity, main RLC entity and / or main MAC entity of PDCP may be an entity that becomes or can become the source side (e.g., switching source, SCGChange destination) when performing synchronous reconfiguration (e.g., switching, SCG Change). The main sub-entity, main RLC entity and / or main MAC entity of PDCP may also be an entity that becomes or can become the object of reconfiguration of RRC that is not synchronous reconfiguration (e.g., switching, SCG Change). The secondary sub-entity, secondary RLC entity and / or secondary MAC entity of PDCP may be an entity that becomes the target side (e.g., switching destination, SCG Change destination) when performing synchronous reconfiguration (e.g., switching, SCG Change). The secondary sub-entity, secondary RLC entity and / or secondary MAC entity of PDCP may be an entity that exists only in the state where the main sub-entity, main RLC entity and / or main MAC entity of PDCP exist. In addition, the main sub-entity, main RLC entity and / or main MAC entity of PDCP may be an entity that exists in the state where the secondary sub-entity, secondary RLC entity and / or secondary MAC entity of PDCP do not exist.

[0892] Various aspects of the terminal device according to the embodiment of the present invention will be described below.

[0893] (1) The first embodiment of the present invention is a terminal device that communicates with a base station device, in which a PDCP entity is set, and the PDCP entity has a first encryption algorithm and a first encryption key associated with a first RLC entity, a first integrity protection algorithm and a first integrity protection key associated with the first RLC entity, and a first header compression state for downlink reception from the first RLC entity. Based on a first request made by an upper layer, a second encryption algorithm and a second encryption key provided by the upper layer are associated with a second RLC entity, a second integrity protection algorithm and a second integrity protection key provided by the upper layer are associated with the second RLC entity, and a second header compression protocol is started in the NC (NoContext) state of a single direction mode for downlink reception from the second RLC entity as a second header compression state.

[0894] (2) The second embodiment of the present invention is a terminal device that communicates with the base station device described in the first embodiment of the present invention, wherein the PDCP entity further uses the first encryption algorithm, the first encryption key and the COUNT value obtained according to the header of the PDCP DATA PDU to decode when the first RLC entity receives the PDCP DATA PDU, uses the first integrity protection algorithm, the first integrity protection key and the COUNT value obtained according to the header of the PDCP DATA PDU to perform integrity verification, and uses the first header compression state to restore the header; and when the second RLC entity receives the PDCP DATA PDU, uses the second encryption algorithm, the second encryption key and the COUNT value obtained according to the header of the PDCP DATA PDU to decode, uses the second integrity protection algorithm, the second integrity protection key and the COUNT value obtained according to the header of the PDCP DATA PDU to perform integrity verification, and uses the second header compression state to restore the header.

[0895] (3) A third embodiment of the present invention is a terminal device for communicating with a base station device as described in the first embodiment of the present invention or the second embodiment of the present invention, wherein the first RLC entity is a primary RLC entity and the second RLC entity is a secondary RLC entity.

[0896] (4) The fourth embodiment of the present invention is a terminal device that communicates with a base station device as described in the first embodiment of the present invention, the second embodiment of the present invention, or the third embodiment of the present invention, wherein the PDCP entity further sets the second RLC entity as a main RLC entity when the first RLC entity releases or stops or detects a second request.

[0897] (5) The fifth embodiment of the present invention is a terminal device that communicates with a base station device as described in the first embodiment of the present invention, the second embodiment of the present invention, the third embodiment of the present invention, or the fourth embodiment of the present invention, wherein the PDCP entity performs the processing described in the first embodiment of the present invention, the second embodiment of the present invention, the third embodiment of the present invention, or the fourth embodiment of the present invention when the upper layer performs the first setting.

[0898] (6) The sixth embodiment of the present invention is a method for a terminal device to communicate with a base station device, wherein a PDCP entity is set in the terminal device, and the PDCP entity has a first encryption algorithm and a first encryption key associated with a first RLC entity, a first integrity protection algorithm and a first integrity protection key associated with the first RLC entity, and a first header compression state for downlink reception from the first RLC entity. Based on a first request made by an upper layer, a second encryption algorithm and a second encryption key provided by the upper layer are associated with a second RLC entity, a second integrity protection algorithm and a second integrity protection key provided by the upper layer are associated with the second RLC entity, and a second header compression protocol is started in the NC (No Context) state of a single direction mode for downlink reception from the second RLC entity as a second header compression state.

[0899] (7) The seventh embodiment of the present invention is a method of a terminal device communicating with a base station device as described in the sixth embodiment of the present invention, wherein the PDCP entity further uses the first encryption algorithm, the first encryption key and the COUNT value obtained according to the header of the PDCP DATA PDU to decode when the first RLC entity receives the PDCP DATA PDU, uses the first integrity protection algorithm, the first integrity protection key and the COUNT value obtained according to the header of the PDCP DATA PDU to perform integrity verification, and uses the first header compression state to restore the header; and when the second RLC entity receives the PDCP DATA PDU, uses the second encryption algorithm, the second encryption key and the COUNT value obtained according to the header of the PDCP DATA PDU to decode, uses the second integrity protection algorithm, the second integrity protection key and the COUNT value obtained according to the header of the PDCP DATA PDU to perform integrity verification, and uses the second header compression state to restore the header.

[0900] (8) The eighth embodiment of the present invention is a method of a terminal device communicating with a base station device as described in the sixth embodiment of the present invention or the seventh embodiment of the present invention, wherein the first RLC entity is a primary RLC entity and the second RLC entity is a secondary RLC entity.

[0901] (9) The ninth embodiment of the present invention is a method of a terminal device communicating with a base station device according to the sixth embodiment of the present invention, the seventh embodiment of the present invention, or the eighth embodiment of the present invention, wherein the PDCP entity further sets the second RLC entity as a main RLC entity when the first RLC entity releases or stops or detects a second request.

[0902] (10) The tenth embodiment of the present invention is a method of a terminal device communicating with a base station device as described in the sixth embodiment of the present invention, the seventh embodiment of the present invention, the eighth embodiment of the present invention, or the ninth embodiment of the present invention, wherein the PDCP entity performs the processing described in the sixth embodiment of the present invention, the seventh embodiment of the present invention, the eighth embodiment of the present invention, or the ninth embodiment of the present invention when the upper layer makes a first setting.

[0903] The program running in the device of one embodiment of the present invention may be a program that controls the Central Processing Unit (CPU) and the like to realize the functions of the above-mentioned embodiment of one embodiment of the present invention and enables the computer to function. The program or the information processed by the program is temporarily read into a volatile memory such as a Random Access Memory (RAM) or stored in a non-volatile memory such as a flash memory or a Hard Disk Drive (HDD) during processing, and is read, modified, or written by the CPU as needed.

[0904] It should be noted that a part of the device in the above-mentioned embodiment can be implemented by a computer. In this case, the program for implementing the control function can be recorded in a computer-readable recording medium, and the program recorded in the recording medium can be read into a computer system and executed to implement it. The "computer system" mentioned here refers to a computer system built into the device, and is set to include hardware such as an operating system and peripherals. In addition, the "computer-readable recording medium" can be any one of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, etc.

[0905] Furthermore, the "computer-readable recording medium" may include: a medium that stores the program dynamically for a short period of time, such as a communication line when the program is transmitted via a network such as the Internet or a communication line such as a telephone line; a medium that stores the program for a fixed period of time, such as a volatile memory inside a computer system that serves as a server or client in this case. In addition, the program may be a program for realizing a part of the functions described above, or a program that can realize the functions described above by combining with a program already recorded in a computer system.

[0906] In addition, each functional block or each feature of the device used in the above-mentioned embodiments can be implemented or executed by a circuit, that is, typically by an integrated circuit or multiple integrated circuits. Circuits designed in a manner to perform the functions described in this specification may include: a general-purpose processor, a digital signal processor (DSP), an integrated circuit for a specific purpose (ASIC), a field programmable gate array (FPGA) or other programmable logic elements, discrete gates or transistor logic, discrete hardware parts, or a combination thereof. The general-purpose processor may be a microprocessor, and the processor may also be an existing processor, controller, microcontroller or state machine instead. The general-purpose processor or the circuits described above may be composed of digital circuits or analog circuits. In addition, in the case of an integrated circuit technology that replaces existing integrated circuits as semiconductor technology advances, integrated circuits based on this technology may also be used.

[0907] It should be noted that the invention of the present application is not limited to the above-mentioned embodiments. In the embodiments, an example of a device is described, but the invention of the present application is not limited thereto and can be applied to fixed or non-movable electronic devices set up indoors and outdoors, such as AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other terminal devices or communication devices such as other living equipment.

[0908] The embodiments of the present invention are described in detail with reference to the accompanying drawings, but the specific configuration is not limited to the present embodiment, and also includes design changes within the scope of the gist of the present invention. In addition, a scheme of the present invention can be variously changed within the scope shown in the technical scheme, and the embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. In addition, it also includes a configuration obtained by replacing the elements that have the same effect as the elements recorded in the above-mentioned embodiments with each other.

[0909] Industrial Applicability

[0910] One aspect of the present invention can be used for example in a communication system, a communication device (such as a mobile phone device, a base station device, a wireless LAN device, or a sensor device), an integrated circuit (such as a communication chip), a program, or the like.

[0911] Description of Reference Numerals

[0912] 100 E-UTRA

[0913] 102 eNB

[0914] 104 EPC

[0915] 106 NR

[0916] 108 gNB

[0917] 110 5GC

[0918] 112, 114, 116, 118, 120, 124 interfaces

[0919] 122 UE

[0920] 200, 300 PHY

[0921] 202, 302 MAC

[0922] 204, 304 RLC

[0923] 206, 306 PDCP

[0924] 208, 308 RRC

[0925] 310 SDAP

[0926] 210, 312 NAS

[0927] 500, 604 Receiving Department

[0928] 502, 602 Processing Department

[0929] 504, 600 Sending Department

[0930] 2200 PDCP entity

[0931] 2202, 2204 RLC Entity

Claims

1. A terminal device, the terminal device communicating with a base station device, the terminal device comprising: a receiving unit configured to receive a radio resource control RRC reconfiguration message from the base station device; and a processing unit, wherein The processing unit is configured to: Establishing a first packet data convergence protocol PDCP entity associated with the first data radio bearer DRB and a second PDCP entity associated with the second DRB; causing the first PDCP entity to apply a first encryption algorithm, a first encryption key, a first integrity protection algorithm, and a first integrity protection key; and causing the second PDCP entity to apply the first encryption algorithm, the second encryption algorithm, the first encryption key, the second encryption key, the first integrity protection algorithm, the second integrity protection algorithm, the first integrity protection key, and the second integrity protection key, The first DRB is a DRB for not performing a first request based on the RRC reconfiguration message, The second DRB is a DRB for executing the first request based on the RRC reconfiguration message, The first request is a request for handover to perform transmission / reception of user data in the target cell and to perform continued transmission / reception of user data in the source cell, and The first request is applied to a radio bearer associated with a PDCP entity.

2. The terminal device according to claim 1, wherein: The processing unit is further configured to: When first data is received from the source cell, the PDCP entity is enabled to decrypt the first data using the first encryption algorithm and the first encryption key; When second data is received from the target cell, the PDCP entity is enabled to decrypt the second data using the second encryption algorithm and the second encryption key; When first data is received from the source cell, enable the PDCP entity to verify the first data using the first integrity protection algorithm and the first integrity protection key; and In a case where second data is received from the target cell, the PDCP entity is caused to perform verification on the second data using the second integrity protection algorithm and the second integrity protection key.

3. A base station device for communicating with a terminal device, the base station device comprising: a sending unit configured to send a radio resource control RRC reconfiguration message to the terminal device; and a processing unit, wherein The processing unit is configured to: Enable the terminal device to establish a first packet data convergence protocol PDCP entity associated with the first data radio bearer DRB and a second PDCP entity associated with the second DRB; causing the first PDCP entity to apply a first encryption algorithm, a first encryption key, a first integrity protection algorithm, and a first integrity protection key; and causing the second PDCP entity to apply the first encryption algorithm, the second encryption algorithm, the first encryption key, the second encryption key, the first integrity protection algorithm, the second integrity protection algorithm, the first integrity protection key, and the second integrity protection key, The first DRB is a DRB for not performing a first request based on the RRC reconfiguration message, The second DRB is a DRB for executing the first request based on the RRC reconfiguration message, The first request is a request for handover to perform transmission / reception of user data in the target cell and to perform continued transmission / reception of user data in the source cell, and The first request is applied to a radio bearer associated with a PDCP entity.

4. The base station device according to claim 3, wherein: The processing unit is further configured to: When first data is received from the source cell through the terminal device, the PDCP entity decrypts the first data using the first encryption algorithm and the first encryption key; When second data is received from the target cell through the terminal device, the PDCP entity is enabled to decrypt the second data using the second encryption algorithm and the second encryption key; When first data is received from the source cell through the terminal device, causing the PDCP entity to perform verification on the first data using the first integrity protection algorithm and the first integrity protection key; and In a case where second data is received from the target cell through the terminal device, the PDCP entity is caused to perform verification on the second data using the second integrity protection algorithm and the second integrity protection key.

5. A method for a terminal device for communicating with a base station device, the method comprising: receiving a radio resource control (RRC) reconfiguration message from the base station device; Establishing a first packet data convergence protocol PDCP entity associated with the first data radio bearer DRB and a second PDCP entity associated with the second DRB; causing the first PDCP entity to apply a first encryption algorithm, a first encryption key, a first integrity protection algorithm, and a first integrity protection key; and causing the second PDCP entity to apply the first encryption algorithm, the second encryption algorithm, the first encryption key, the second encryption key, the first integrity protection algorithm, the second integrity protection algorithm, the first integrity protection key, and the second integrity protection key, wherein The first DRB is a DRB for not performing a first request based on the RRC reconfiguration message, The second DRB is a DRB for executing the first request based on the RRC reconfiguration message, The first request is a request for handover to perform transmission / reception of user data in the target cell and to perform continued transmission / reception of user data in the source cell, and The first request is applied to a radio bearer associated with a PDCP entity.

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