Data transmission method and device

Abstract

The invention discloses a data transmission method and device. The method comprises: a first base station centralized entity receiving a first message sent by a core network, the first message comprising at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of downlink data about to arrive; the first base station concentration entity sends a first request message and / or a first paging message to the first base station separation entity, the first request message comprising at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, and data radio bearer configuration; the first paging message comprises an inactive state downlink small data transmission indication. According to the invention, the technical problem that the radio bearer type of the small data packet is not clearly identified when the downlink small data packet is transmitted at present is solved.

Description

Technical Field

[0001] The present application relates to the field of wireless communications, and in particular to a method and device for data transmission. Background Art

[0002] 5G NR introduces a new state, the Inactive state, which aims to allow the UE to quickly enter the connected state to send data, while reducing the signaling overhead caused by the mobile process and state transfer process. In the RRC Inactive state, the UE's non-access stratum (NAS) remains in the connected state, but the air interface corresponding to the UE's access stratum (AS) is temporarily suspended. In versions before 3GPP Rel-16, if there is a small data packet to be transmitted in the Inactive state, the terminal first needs to change from the Inactive state to the Connected state, and then send the data after the control plane and user plane on the network side establish a connection. In order to reduce latency and signaling overhead, 3GPP carried out research on Mobile Original Small Data Transmission (MO-SDT) for uplink small data transmission in Rel-17, with the aim of reducing the access delay of the terminal sending uplink small data packets in the Inactive state. Similarly, in order to reduce the downlink small data transmission delay, 3GPP Rel-18 carried out research on Mobile Terminated Small Data Transmission (MT-SDT) for downlink small data transmission.

[0003] According to the existing TS38.423 protocol, when the source base station receives downlink data (or needs to page the terminal due to other reasons), the source base station sends a RAN paging message to the target base station through the Xn interface, which includes a paging identifier, a paging reason, etc.

[0004] According to the existing TS38.473 protocol, the centralized unit (CU) and distributed unit (DU) of the gNB establish the UE context through the UE Context Setup process. The gNB-CU first sends a UE CONTEXT SETUP REQUEST message to the gNB-DU. After the gNB-DU successfully establishes the UE context, it replies with a UE CONTEXT SETUP RESPONSE message to the gNB-CU.

[0005] Therefore, in order to support the MT-SDT process of inactive downlink small data transmission, the source base station needs to send MT-SDT related information to the target base station through the XnAP message, and the target base station CU and DU need to establish relevant UE contexts to support MT-SDT data transmission. However, the current 3GPP 5G protocol cannot meet the requirements and needs to be enhanced in a new way to better support the transmission of inactive downlink small data packets. Summary of the invention

[0006] The embodiments of the present application provide a method and apparatus for data transmission, so as to at least solve the current technical problem of not clearly identifying the radio bearer type of a small data packet when transmitting a downlink small data packet.

[0007] According to one aspect of an embodiment of the present application, a method for data transmission is provided, including: a first base station centralized entity receives a first message sent by a core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of downlink data to be arrived; the first base station centralized entity sends a first request message and / or a first paging message to a first base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, and data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0008] Optionally, the first downlink signaling indication includes at least one of the following: a downlink signaling indication, a downlink signaling size indication, wherein the downlink signaling indication is used to indicate that the first base station receives downlink signaling sent by the core network, and the downlink signaling size indication is used to indicate the size of the downlink signaling sent by the core network received by the first base station.

[0009] Optionally, the first indication of downlink user plane data includes at least one of the following: a downlink user plane data indication, a downlink user plane data size indication, wherein the downlink user plane data indication is used to indicate that the first base station receives user plane data sent by the core network, and the downlink user plane data size indication is used to indicate the size of user plane data sent by the core network to be received by the first base station.

[0010] Optionally, the first indication of the upcoming downlink data includes at least one of the following: an indication of the upcoming downlink user plane data, an indication of the upcoming downlink signaling, wherein the indication of the upcoming downlink user plane data is used to indicate that the core network is about to send downlink user plane data to the first base station, and the indication of the upcoming downlink signaling is used to indicate that the core network is about to send downlink signaling to the first base station.

[0011] Optionally, the first base station centralized entity sends a second message to the second base station, and the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to the inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to the inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to the inactive downlink small data transmission dedicated bearer.

[0012] Optionally, when the downlink small data transmission data size includes a downlink signaling indication, it is determined to establish a signaling radio bearer; when the downlink small data transmission data size includes a downlink user plane data indication, it is determined to establish a data radio bearer.

[0013] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0014] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0015] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0016] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0017] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0018] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0019] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0020] Optionally, the value range of the signaling radio bearer identifier is a first interval, the first value in the first interval represents a signaling radio bearer used to transmit application layer measurement reporting information, and the second value in the first interval represents a signaling radio bearer used to transmit experience quality information to the auxiliary node, wherein the first value is smaller than the second value.

[0021] Optionally, the value range of the data radio bearer identifier is a second interval.

[0022] Optionally, after the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the signaling wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the signaling wireless bearer for the inactive downlink small data transmission indicated by the signaling wireless bearer identifier.

[0023] Optionally, after the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the data wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the data wireless bearer for the inactive downlink small data transmission indicated by the data wireless bearer identifier.

[0024] Optionally, when the first request message is a terminal context establishment request message and the first base station separation entity successfully establishes the terminal context based on the first request message, the first base station centralized entity receives a terminal context establishment response message fed back by the first base station separation entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0025] Optionally, the terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

[0026] Optionally, the data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

[0027] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0028] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0029] Optionally, the data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, and at least one data radio bearer establishment failure item includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0030] Optionally, when the first request message is a terminal context modification request message and the first base station separation entity successfully modifies the terminal context based on the first request message, the first base station centralized entity receives a terminal context modification response message fed back by the first base station separation entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0031] Optionally, the terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

[0032] Optionally, the data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include a data radio bearer identifier.

[0033] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

[0034] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0035] Optionally, the signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification items include signaling radio bearer identifiers.

[0036] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0037] Optionally, when the first paging message received by the first base station separation entity includes an inactive downlink small data transmission indication and the first base station separation entity supports the inactive downlink small data transmission indication, the inactive downlink small data transmission indication is sent to the user terminal via the first base station separation entity.

[0038] Optionally, the method also includes: the first base station centralized entity receives a user terminal context acquisition request message sent by the second base station, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

[0039] Optionally, the method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the first base station centralized entity sends a user terminal context response message to the second base station, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

[0040] Optionally, the method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the first base station centralized entity sends a partial user terminal context message to the second base station, wherein the partial user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0041] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0042] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0043] Optionally, the first message further includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0044] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0045] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0046] Optionally, the first base station centralized entity includes a first base station centralized entity user plane and a first base station centralized entity control plane. After the first base station centralized entity receives the second message, the first base station centralized entity user plane sends a downlink data notification message to the first base station centralized entity control plane.

[0047] Optionally, the downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

[0048] According to another aspect of an embodiment of the present application, a method for data transmission is also provided, including: a first base station separation entity receives a first request message and / or a first paging message sent by a first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0049] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0050] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0051] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0052] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0053] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0054] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0055] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0056] Optionally, when the first request message is a terminal context establishment request message and the first base station separation entity successfully establishes the terminal context based on the first request message, the first base station separation entity feeds back a terminal context establishment response message to the first base station centralized entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0057] Optionally, the terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

[0058] Optionally, the data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

[0059] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0060] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0061] Optionally, the data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, and at least one data radio bearer establishment failure item includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0062] Optionally, when the first request message is a terminal context modification request message and the first base station separation entity successfully modifies the terminal context based on the first request message, the first base station separation entity feeds back a terminal context modification response message to the first base station centralized entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0063] Optionally, the terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

[0064] Optionally, the data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include a data radio bearer identifier.

[0065] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

[0066] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0067] Optionally, the signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification items include signaling radio bearer identifiers.

[0068] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0069] According to another aspect of an embodiment of the present application, a method for data transmission is also provided, including: a second base station receives a second message sent by a centralized entity of the first base station, the second message comprising at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to an inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to an inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to an inactive downlink small data transmission dedicated bearer.

[0070] Optionally, when the downlink small data transmission data size includes a downlink signaling indication, it is determined to establish a signaling radio bearer; when the downlink small data transmission data size includes a downlink user plane data indication, it is determined to establish a data radio bearer.

[0071] Optionally, the method further includes: the second base station receives a radio resource control recovery request message sent by the user terminal, wherein the recovery reason of the radio resource control recovery request message is an inactive downlink small data transmission indication.

[0072] Optionally, the method also includes: the second base station sends a user terminal context acquisition request message to the first base station centralized entity, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

[0073] Optionally, the method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the second base station receives a user terminal context response message sent by the first base station centralized entity, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

[0074] Optionally, the method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the second base station receives part of the user terminal context message sent by the first base station centralized entity, wherein the part of the user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0075] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0076] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0077] Optionally, the second base station includes a second base station centralized entity user plane and a second base station centralized entity control plane. After the second base station centralized entity receives the second message, the second base station centralized entity user plane sends a downlink data notification message to the second base station centralized entity control plane.

[0078] Optionally, the downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

[0079] Optionally, the second base station includes a second base station centralized entity and a second base station separated entity, wherein the second base station centralized entity sends a first request message and / or a first paging message to the second base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; and the first paging message includes an inactive downlink small data transmission indication.

[0080] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0081] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0082] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0083] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0084] According to another aspect of an embodiment of the present application, a data transmission device is also provided, including: a first receiving module, used to receive a first message sent by a core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of upcoming downlink data; a first sending module, used to send a first request message and / or a first paging message to a first base station separation entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0085] According to another aspect of an embodiment of the present application, another data transmission device is provided, including: a second receiving module, used to receive a first request message and / or a first paging message sent by a first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0086] According to another aspect of an embodiment of the present application, another data transmission device is provided, including: a third receiving module, configured to receive a second message sent by a first base station centralized entity, wherein the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to an inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to an inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data data volume indication is used to characterize the data volume of all downlink user plane data mapped to an inactive downlink small data transmission dedicated bearer.

[0087] In an embodiment of the present application, a first message sent by a core network is received by a first base station centralized entity, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of downlink data to be arrived; the first base station centralized entity sends a first request message and / or a first paging message to the first base station separation entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication, thereby achieving the purpose of the base station establishing a UE context according to the downlink small data related information in the first message, thereby realizing a better technical effect of supporting the transmission of inactive downlink small data packets, and further solving the current technical problem of not clearly identifying the radio bearer type of small data packets when transmitting downlink small data packets. BRIEF DESCRIPTION OF THE DRAWINGS

[0088] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0089] Figure 1 is a flowchart of a method for data transmission provided according to an embodiment of the present application;

[0090] Figure 2 is a partial flow chart a of a method for data transmission provided by an embodiment of the present application;

[0091] Figure 3 is a partial flow chart b of a method for data transmission provided in an embodiment of the present application;

[0092] Figure 4 is a partial flow chart c of a method for data transmission provided in an embodiment of the present application;

[0093] Figure 5 This is a partial flowchart d of a data transmission method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0094] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0095] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0096] First, some nouns or terms that appear in the process of explaining the embodiments of the present application are subject to the following explanations:

[0097] 3GPP (3rd Generation Partnership Project): An international standardization organization dedicated to developing standards for mobile communication technologies. It is composed of major telecommunications standardization organizations around the world, including the European Telecommunications Standards Institute (ETSI), the American Telecommunications Industry Association (ATIS), and the China Telecommunications Technology Standardization Research Institute (CATR). 3GPP's mission is to develop and maintain standards for mobile communication technologies, including mobile network architecture, wireless access technology, protocol specifications, etc., to promote the development and interoperability of the global mobile communication industry.

[0098] NR (New Radio): refers to the new generation of air interface technology used for wireless communications in 5G networks. This technology can work in both independent and non-independent modes, with higher spectrum efficiency, lower latency, larger capacity and higher reliability, and can support more users to connect simultaneously, faster data transmission speeds and wider coverage.

[0099] RRC (Radio Resource Control): refers to a technology for effectively managing and allocating radio resources in mobile communication systems. It is responsible for controlling the radio resources in the radio access network, including frequency resources, time slot resources, power resources, etc., to meet the communication needs of users and ensure the efficient operation of the network. It mainly includes the following functions: connection management, frequency and power control, neighboring cell management, and allocation and scheduling of radio resources.

[0100] AMF (Access and Mobility Management Function): It is an important functional module in the 5G core network, responsible for access and mobility management. It mainly includes the following functions: managing the access process of the device, managing the mobility of the device, and managing the session of the device, so as to provide reliable network connection and communication services for the device.

[0101] PDCP (Packet Data Convergence Protocol): It is a protocol layer in LTE (Long Term Evolution) wireless communication technology. The PDCP layer is located at the third layer in the LTE protocol stack and is responsible for processing packet data on the IP layer, including compression, encryption, integrity protection and retransmission functions. It plays an important role in improving network efficiency and ensuring data security.

[0102] MAC (Medium Access Control): is a term used in computer networks to describe the method of controlling multiple devices to share the same physical media. It defines the rules and protocols for data transmission on the shared media. MAC is mainly responsible for the following: media access control, media frame format, media conflict detection and handling, and media access control protocol.

[0103] RLC (Radio Link Control) protocol: A protocol for data transmission and error control in wireless communication systems. It is located at the data link layer and is responsible for processing data segmentation, reorganization and retransmission, as well as controlling the reliability and order of data. The RLC protocol can provide different service qualities as needed, including connectionless mode without confirmation, connectionless mode with confirmation, and connection mode with confirmation. These service qualities can be selected according to application requirements to balance the reliability and delay of data transmission.

[0104] PDU (Protocol Data Unit): PDU is the smallest unit of data transmitted during the communication process, which can also be understood as a data packet. PDU contains some specific fields and data for transmission and processing in different levels of network protocols.

[0105] DRB (Data Radio Bearer): is an important concept in mobile communication technologies such as LTE and 5G, used to carry user data and transmit control signaling. In LTE and 5G, DRB is implemented through logical channels and transport channels. Logical channels are used to assign different types of user data to different transport channels, while transport channels are responsible for transmitting data to base stations or user devices. DRB can support multiple logical channels and transport channels at the same time to meet different types of communication needs.

[0106] PUSCH (Physical Uplink Shared Channel): A physical channel used in LTE and 5G wireless communication systems. It is used to transmit uplink data between user equipment (UE) and base stations.

[0107] The current 3GPP standard cannot better support the inactive downlink small data transmission process, and there are the following problems:

[0108] 1. The source base station cannot send MT-SDT related information to the target base station through the XnAP message: The current protocol does not support the source base station to send MT-SDT related information, including the data volume information of MT-SDT data and / or signaling, to the target base station through the XnAP message to assist the target base station in better determining whether to initiate the MT-SDT process;

[0109] 2. The target base station separation architecture CU and DU cannot establish a signaling radio bearer for MT-SDT: According to the current protocol, the target base station CU cannot learn whether the MT-SDT related message transmitted by XnAP includes downlink signaling information. Therefore, it cannot instruct the target base station DU to establish a related signaling radio bearer, thereby failing to implement MT-SDT transmission;

[0110] 3. When new data arrives at the SDT radio bearer, the gNB-CU-UP cannot send complete MT-SDT related information (including MT-SDT indication, MT-SDT data and / or signaling data size) to the gNB-CU-CP to assist the CU-CP in making more reasonable decisions to better support MT-SDT transmission;

[0111] 4. Unable to distinguish the connection recovery process initiated by the terminal due to downlink SDT: In the existing protocol, only when the inactive terminal has small uplink data, the terminal sends a connection recovery request to the network, and the receiving base station sends the uplink SDT related information to the anchor base station to obtain the terminal context information. According to the current standard, the anchor base station cannot distinguish the connection recovery process initiated by the terminal due to downlink SDT, and cannot better support SDT transmission.

[0112] In order to solve the above problems, an embodiment of the present application provides a method for data transmission, which is described in detail below.

[0113] Figure 1 is a flow chart of a method for data transmission according to an embodiment of the present application. Figure 1 As shown, the method comprises the following steps:

[0114] Step S102: The first base station centralized entity receives a first message sent by the core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of upcoming downlink data.

[0115] In the above step S102, the first base station obtains downlink data and / or downlink signaling from the core network, and all received downlink data and / or downlink signaling are mapped to a specific wireless bearer for small data transmission, and the total data volume of the downlink data and / or downlink signaling meets the inactive downlink small data transmission (Mobile Terminated Small Data Transmission, MT-SDT) condition.

[0116] In addition, the first base station can obtain information such as the data type of signaling and / or data mapped to a specific wireless bearer for small data transmission from the core network; the first base station can judge based on the data and related information sent by the core network that it can send the received data and signaling to the inactive terminal through the inactive downlink small data transmission process.

[0117] Step S104, the first base station centralized entity sends a first request message and / or a first paging message to the first base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0118] Optionally, the first downlink signaling indication includes at least one of the following: a downlink signaling indication, a downlink signaling size indication, wherein the downlink signaling indication is used to indicate that the first base station receives downlink signaling sent by the core network, and the downlink signaling size indication is used to indicate the size of the downlink signaling sent by the core network received by the first base station.

[0119] Optionally, the first indication of downlink user plane data includes at least one of the following: a downlink user plane data indication, a downlink user plane data size indication, wherein the downlink user plane data indication is used to indicate that the first base station receives user plane data sent by the core network, and the downlink user plane data size indication is used to indicate the size of user plane data sent by the core network to be received by the first base station.

[0120] Optionally, the first indication of the upcoming downlink data includes at least one of the following: an indication of the upcoming downlink user plane data, an indication of the upcoming downlink signaling, wherein the indication of the upcoming downlink user plane data is used to indicate that the core network is about to send downlink user plane data to the first base station, and the indication of the upcoming downlink signaling is used to indicate that the core network is about to send downlink signaling to the first base station.

[0121] Optionally, the first base station centralized entity sends a second message to the second base station, and the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to the inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to the inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to the inactive downlink small data transmission dedicated bearer.

[0122] In an embodiment of the present application, the first base station sends information related to inactive downlink small data transmission (MT-SDT) to other base stations (including the second base station) in a radio notification area (RANNotification area, RNA) through a radio access network (RAN) paging message of an Xn interface. The MT-SDT information (such as the information included in the above-mentioned second message) includes but is not limited to the following information:

[0123] 1) Downlink small data transmission indication: enumeration value, "yes" indicates downlink small data transmission, and "no" indicates non-downlink small data transmission.

[0124] 2) Downlink small data transmission data volume: an integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0125] 3) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission includes downlink signaling.

[0126] 4) Downlink signaling data size: an integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0127] 5) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes the downlink user plane data.

[0128] 6) Data volume of downlink user plane data: an integer value ranging from 1 to 96000, indicating the data volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0129] Optionally, when the downlink small data transmission data size includes a downlink signaling indication, it is determined to establish a signaling radio bearer; when the downlink small data transmission data size includes a downlink user plane data indication, it is determined to establish a data radio bearer.

[0130] In an embodiment of the present application, if the size of the downlink small data transmission data volume includes a downlink signaling indication, it means that the total data of the received inactive downlink small data transmission includes signaling, and a signaling radio bearer needs to be established for it; otherwise, it means that the total data of the received inactive downlink small data transmission includes only user plane data, and only a data radio bearer needs to be established.

[0131] After the second base station receives the Xn RAN Paging message sent by the first base station, the second base station centralized entity user plane (Central Unit-User Plane, CU-UP) sends the inactive downlink small data transmission related information to the second base station centralized entity control plane (Central Unit-Control Plane, CU-CP) through a downlink data notification message to assist the second base station control plane entity in determining whether to initiate an inactive downlink small data transmission process, including but not limited to the following contents:

[0132] 1) Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0133] 2) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0134] 3) Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0135] 4) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0136] 5) Data volume of downlink user plane data: an integer value ranging from 1 to 96000, indicating the data volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0137] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0138] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0139] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0140] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0141] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0142] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0143] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0144] Optionally, the value range of the signaling radio bearer identifier is a first interval, the first value in the first interval represents a signaling radio bearer used to transmit application layer measurement reporting information, and the second value in the first interval represents a signaling radio bearer used to transmit experience quality information to the auxiliary node, wherein the first value is smaller than the second value.

[0145] Optionally, the value range of the data radio bearer identifier is a second interval.

[0146] In an embodiment of the present application, the second base station centralized entity (CU) sends a UE context establishment request message (that is, the above-mentioned terminal context establishment request message) to the second base station separation entity (DU). In another optional embodiment, the first base station centralized entity (CU) may also send a UE context establishment request message to the first base station separation entity (DU). If the downlink small data transmission data packet contains downlink data, the request message carries data radio bearer establishment list information; if the downlink small data transmission data packet contains downlink signaling, the request message carries signaling radio bearer establishment list information. Specifically, the UE context establishment request message includes but is not limited to the following information:

[0147] 1) Signaling radio bearer establishment list

[0148] a. Signaling radio bearer establishment project, including: signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumeration value, which can be 0 to 5 (ie, the first interval above), 0 identifies SRB0, 2 indicates SRB2, 3 indicates SRB3 ...;

[0149] b. Radio link layer control protocol RLC bearer configuration for small data transmission;

[0150] 2) Data radio bearer establishment list

[0151] a. Data radio bearer establishment project: Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, which can be 1 to 32 (ie, the second interval above), each number identifies a separate DRB;

[0152] b. RLC bearer configuration for small data transmission.

[0153] In an embodiment of the present application, the second base station centralized entity (CU) sends a UE context modification request message (i.e., the above-mentioned terminal context modification request message) to the second base station separated entity (DU). In another optional embodiment, the first base station centralized entity (CU) may also send a UE context modification request message to the first base station separated entity (DU).

[0154] When the second base station centralized entity (CU) sends a UE context modification request message to the second base station separation entity, if downlink data is newly added to the downlink small data transmission data packet (that is, the original downlink small data packet only contains downlink signaling), the request message carries data radio bearer establishment list information.

[0155] If downlink signaling is newly added to the downlink small data transmission data packet (i.e., the original downlink small data packet contains only downlink data), the request message carries the signaling radio bearer establishment list information, and the UE context modification request message includes but is not limited to the following information:

[0156] 1. Signaling radio bearer establishment list

[0157] 1) Signaling radio bearer establishment project

[0158] a. Signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumerated value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, 5 indicates SRB5...;

[0159] b. RLC bearer configuration for small data transmission;

[0160] c. Small data transmission indication establishment: used to indicate the signaling radio bearer of small data transmission SDT.

[0161] 2. Data radio bearer establishment list

[0162] 2) Data wireless bearer establishment project

[0163] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately;

[0164] b. RLC bearer configuration for small data transmission;

[0165] c. Small data transmission indication establishment: used to indicate the data radio bearer of small data transmission SDT.

[0166] Optionally, after the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the signaling wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the signaling wireless bearer for the inactive downlink small data transmission indicated by the signaling wireless bearer identifier.

[0167] Optionally, after the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the data wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the data wireless bearer for the inactive downlink small data transmission indicated by the data wireless bearer identifier.

[0168] Specifically, after the second base station separation entity (DU) receives the UE context establishment request message sent by the second base station centralized entity (CU), if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID.

[0169] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0170] Similarly, after the second base station separation entity receives the UE context modification request message sent by the second base station concentration entity, the corresponding radio bearer is established according to the data radio bearer and signaling radio bearer indication information therein;

[0171] Among them, if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID;

[0172] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0173] Optionally, when the first request message is a terminal context establishment request message and the first base station separation entity successfully establishes the terminal context based on the first request message, the first base station centralized entity receives a terminal context establishment response message fed back by the first base station separation entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0174] Optionally, the terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

[0175] Optionally, the data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

[0176] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0177] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0178] Optionally, the data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, and at least one data radio bearer establishment failure item includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0179] Specifically, if the second base station separation entity (DU) successfully establishes the UE context, a UE context establishment response message is sent to the second base station centralized entity (CU) to confirm the UE context establishment, wherein, according to the establishment of the data radio bearer and the signaling radio bearer, the UE context establishment response message includes the following content:

[0180] 1. Data radio bearer establishment list

[0181] 1) Data wireless bearer establishment project

[0182] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately.

[0183] 2. Signaling radio bearer establishment list

[0184] 1) Signaling radio bearer establishment project

[0185] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0186] 3. List of signaling radio bearer establishment failures

[0187] 1) Signaling radio bearer establishment failure project

[0188] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0189] b. Cause of establishment failure

[0190] 4. Data radio bearer establishment failure list

[0191] 1) Data radio bearer establishment failure items

[0192] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately;

[0193] b. Establish the reason for failure.

[0194] Optionally, when the first request message is a terminal context modification request message and the first base station separation entity successfully modifies the terminal context based on the first request message, the first base station centralized entity receives a terminal context modification response message fed back by the first base station separation entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0195] Optionally, the terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

[0196] Optionally, the data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include a data radio bearer identifier.

[0197] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

[0198] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0199] Optionally, the signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification items include signaling radio bearer identifiers.

[0200] Specifically, if the second base station separate entity (DU) successfully modifies the UE context, a UE context modification response message is sent to the second base station centralized entity (CU) to confirm the UE context modification, wherein, according to the establishment of the data radio bearer and the signaling radio bearer, the UE context modification response message includes the following content:

[0201] 1. Data radio bearer modification list

[0202] 1) Data radio bearer modification project

[0203] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately.

[0204] 2. Signaling radio bearer establishment failure list

[0205] 1) Signaling radio bearer establishment failure project

[0206] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, and 5 indicates SRB5.

[0207] b. Reason: indicates the reason for the establishment failure

[0208] 3. Signaling radio bearer establishment list

[0209] 1) Signaling radio bearer establishment project

[0210] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0211] 4. Signaling Radio Bearer Modification List

[0212] 1) Signaling radio bearer modification project

[0213] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0214] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0215] In the embodiment of the present application, the paging message carries information related to the inactive downlink small data transmission, which specifically includes but is not limited to the following information:

[0216] 1. Inactive downlink small data transmission indication: enumeration value, "yes" indicates downlink small data transmission, and "no" indicates non-downlink small data transmission.

[0217] 2. Downlink small data transmission data volume: an integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0218] 1) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission includes downlink signaling.

[0219] a. Downlink signaling data size: integer value, ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0220] 2) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes the downlink user plane data.

[0221] a. Downlink user plane data size: integer value, ranging from 1 to 96000, indicating the data size of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0222] Optionally, when the first paging message received by the first base station separation entity includes an inactive downlink small data transmission indication and the first base station separation entity supports the inactive downlink small data transmission indication, the inactive downlink small data transmission indication is sent to the user terminal via the first base station separation entity.

[0223] In an embodiment of the present application, when the paging message received by the first base station separation entity includes inactive downlink small data transmission information, and the first base station separation entity supports the information, the information is used to send an inactive downlink small data transmission paging message to the inactive terminal, and the paging message includes an inactive downlink small data transmission indication.

[0224] Optionally, the method also includes: the first base station centralized entity receives a user terminal context acquisition request message sent by the second base station, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

[0225] In the embodiment of the present application, after receiving the request message, the second base station sends a UE context acquisition request message to the first base station, wherein it is necessary to indicate that the request is initiated by an inactive downlink small data transmission, and the message includes but is not limited to the following information (the following two options are available):

[0226] 1. Inactive downlink small data transmission indication: enumeration type, "true" indicates that there is downlink small data transmission, and "false" indicates that there is no downlink small data transmission.

[0227] This indication is different from the small data transmission indication. The small data transmission indication is for the inactive uplink small data transmission indication, while this indication is for the inactive downlink small data transmission.

[0228] 2. Small data transmission indication, enumeration type, "true" indicates that there is downlink small data transmission, and "false" indicates that there is no downlink small data transmission; at this time, no small data transmission auxiliary information is included to indicate that the transmission is an inactive downlink small data transmission.

[0229] Optionally, the method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the first base station centralized entity sends a user terminal context response message to the second base station, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

[0230] Optionally, the method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the first base station centralized entity sends a partial user terminal context message to the second base station, wherein the partial user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0231] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0232] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0233] In an embodiment of the present application, the first base station determines whether to agree to the user terminal context acquisition request message sent by the second base station based on the downlink data and signaling related information sent by the core network.

[0234] If agreed, a UE context response message is fed back to the second base station, which carries data and signaling related information of the inactive downlink small data transmission, including but not limited to the following information:

[0235] 1. Downlink small data transmission user plane data information

[0236] 1) Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0237] a. A single data packet indicates no subsequent MT-SDT data.

[0238] b. Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets.

[0239] 2) Downlink small data transmission user plane data volume

[0240] a. Single data packet: indicates the amount of data transmitted by the data packet.

[0241] b.Multi-packet: indicates the amount of data transmitted by each packet.

[0242] 2. Downlink small data transmission signaling information

[0243] 1) Downlink small data transmission signaling auxiliary information

[0244] a. Signaling type: Different signaling corresponds to different signaling radio bearers.

[0245] 2) Downlink small data transmission signaling data volume

[0246] If not agreed, part of the UE context message is fed back to the second base station, which carries data and signaling information related to the transmission of inactive downlink small data, including but not limited to the following information:

[0247] 3. Downlink small data transmission user plane data information

[0248] 1) Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0249] a. A single data packet indicates no subsequent MT-SDT data.

[0250] b. Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets.

[0251] 2) Downlink small data transmission user plane data volume

[0252] a. Single data packet: indicates the amount of data transmitted by the data packet.

[0253] b.Multi-packet: indicates the amount of data transmitted by each packet.

[0254] 4. Downlink small data transmission signaling information

[0255] 1) Downlink small data transmission signaling auxiliary information

[0256] a. Signaling type: Different signaling corresponds to different signaling radio bearers.

[0257] 2) Downlink small data transmission signaling data volume

[0258] Optionally, the first message further includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0259] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0260] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0261] In the embodiment of the present application, the data and information obtained by the first base station from the core network (such as the information contained in the first message) include but are not limited to the following:

[0262] 1) Downlink small data transmission user plane data information, including:

[0263] Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"; among them, single data packet means no subsequent MT-SDT data; multiple data packets mean there is subsequent MT-SDT data: it can indicate the number of subsequent data packets.

[0264] Downlink small data transmission user plane data volume: Among them, single data packet: indicates the amount of data transmitted by the data packet; multiple data packets: indicates the amount of data transmitted by each data packet.

[0265] 2) Downlink small data transmission signaling information, including:

[0266] Downlink small data transmission signaling auxiliary information includes: Signaling type: different signaling corresponds to different signaling radio bearers.

[0267] Downlink small data transmission signaling data volume.

[0268] Optionally, the first base station centralized entity includes a first base station centralized entity user plane and a first base station centralized entity control plane. After the first base station centralized entity receives the second message, the first base station centralized entity user plane sends a downlink data notification message to the first base station centralized entity control plane.

[0269] Optionally, the downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

[0270] In an embodiment of the present application, the first base station centralized entity user plane (Central Unit-User Plane, CU-UP) sends the inactive downlink small data transmission related information to the first base station centralized entity control plane (Central Unit-Control Plane, CU-CP) through a downlink data notification message to assist the first base station control plane entity in determining whether to initiate an inactive downlink small data transmission process, including but not limited to the following contents:

[0271] 1. Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0272] 1) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0273] a. Downlink signaling data size: integer value, ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0274] 2) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0275] a. The amount of data for downlink user plane data: an integer value ranging from 1 to 96000, indicating the amount of data mapped to all downlink user plane data on the dedicated bearer for inactive small data transmission;

[0276] An embodiment of the present application also provides another method for data transmission, including: a first base station separation entity receives a first request message and / or a first paging message sent by a first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0277] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0278] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0279] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0280] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

[0281] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0282] Optionally, the signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0283] Optionally, the data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

[0284] Optionally, when the first request message is a terminal context establishment request message and the first base station separation entity successfully establishes the terminal context based on the first request message, the first base station separation entity feeds back a terminal context establishment response message to the first base station centralized entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0285] Optionally, the terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

[0286] Optionally, the data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

[0287] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0288] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0289] Optionally, the data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, and at least one data radio bearer establishment failure item includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

[0290] Optionally, when the first request message is a terminal context modification request message and the first base station separation entity successfully modifies the terminal context based on the first request message, the first base station separation entity feeds back a terminal context modification response message to the first base station centralized entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

[0291] Optionally, the terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

[0292] Optionally, the data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include a data radio bearer identifier.

[0293] Optionally, the signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one signaling radio bearer establishment failure item includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

[0294] Optionally, the signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

[0295] Optionally, the signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification items include signaling radio bearer identifiers.

[0296] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0297] It should be noted that the above-mentioned data transmission method with the first base station separation entity as the execution subject is the same as Figure 1The relevant steps in the data transmission method with the first base station centralized entity as the execution subject are the same, so Figure 1 The relevant explanations in the data transmission method shown are also applicable to the data transmission method with the first base station separation entity as the execution subject, and will not be repeated here.

[0298] An embodiment of the present application also provides another method for data transmission, including: a second base station receives a second message sent by a centralized entity of the first base station, the second message comprising at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to an inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to an inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data data volume indication is used to characterize the data volume of all downlink user plane data mapped to an inactive downlink small data transmission dedicated bearer.

[0299] Optionally, when the downlink small data transmission data size includes a downlink signaling indication, it is determined to establish a signaling radio bearer; when the downlink small data transmission data size includes a downlink user plane data indication, it is determined to establish a data radio bearer.

[0300] In an embodiment of the present application, after the second base station receives the Xn RAN Paging message sent by the first base station, the second base station centralized entity user plane (Central Unit-User Plane, CU-UP) sends the inactive downlink small data transmission related information to the second base station centralized entity control plane (Central Unit-Control Plane, CU-CP) through a downlink data notification message to assist the second base station control plane entity in determining whether to initiate an inactive downlink small data transmission process, including but not limited to the following contents:

[0301] 1) Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0302] 2) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0303] 3) Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0304] 4) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0305] 5) Data volume of downlink user plane data: an integer value ranging from 1 to 96000, indicating the data volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0306] Optionally, the method further includes: the second base station receives a radio resource control recovery request message sent by the user terminal, wherein the recovery reason of the radio resource control recovery request message is an inactive downlink small data transmission indication.

[0307] In an embodiment of the present application, when the paging message received by the second base station separation entity includes inactive downlink small data transmission information, and the second base station separation entity supports the information, the information is used to send an inactive downlink small data transmission paging message to the inactive terminal, and the paging message includes an inactive downlink small data transmission indication.

[0308] After receiving the paging message sent by the second base station, if the inactive state small data transmission condition is met, the inactive state terminal sends an RRC recovery request message to the second base station, in which the recovery reason carried is the inactive state downlink small data transmission indication.

[0309] Optionally, the method also includes: the second base station sends a user terminal context acquisition request message to the first base station centralized entity, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

[0310] In the embodiment of the present application, after receiving the request message, the second base station sends a UE context acquisition request message to the first base station, wherein it is necessary to indicate that the request is initiated by an inactive downlink small data transmission, and the message includes but is not limited to the following information (the following two options are available):

[0311] 1. Inactive downlink small data transmission indication: enumeration type, "true" indicates that there is downlink small data transmission, and "false" indicates that there is no downlink small data transmission.

[0312] This indication is different from the small data transmission indication. The small data transmission indication is for the inactive uplink small data transmission indication, while this indication is for the inactive downlink small data transmission.

[0313] 2. Small data transmission indication, enumeration type, "true" indicates that there is downlink small data transmission, and "false" indicates that there is no downlink small data transmission; at this time, no small data transmission auxiliary information is included to indicate that the transmission is an inactive downlink small data transmission.

[0314] Optionally, the method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the second base station receives a user terminal context response message sent by the first base station centralized entity, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

[0315] Optionally, the method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the second base station receives part of the user terminal context message sent by the first base station centralized entity, wherein the part of the user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

[0316] Optionally, the inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

[0317] Optionally, the inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

[0318] In an embodiment of the present application, the second base station receives downlink data and signaling related information sent by the first base station according to the core network, and determines whether the first base station agrees to the user terminal context acquisition request message sent by the second base station based on the relevant information.

[0319] If agreed, the second base station receives the UE context response message, which carries data and signaling related information of the inactive downlink small data transmission, including but not limited to the following information:

[0320] 1. Downlink small data transmission user plane data information

[0321] 1) Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0322] a. A single data packet indicates no subsequent MT-SDT data.

[0323] b. Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets.

[0324] 2) Downlink small data transmission user plane data volume

[0325] a. Single data packet: indicates the amount of data transmitted by the data packet.

[0326] b.Multi-packet: indicates the amount of data transmitted by each packet.

[0327] 2. Downlink small data transmission signaling information

[0328] 1) Downlink small data transmission signaling auxiliary information

[0329] a. Signaling type: Different signaling corresponds to different signaling radio bearers.

[0330] 2) Downlink small data transmission signaling data volume

[0331] If not agreed, the second base station receives part of the UE context message, which carries data and signaling information related to the transmission of inactive downlink small data, including but not limited to the following information:

[0332] 3. Downlink small data transmission user plane data information

[0333] 1) Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0334] a. A single data packet indicates no subsequent MT-SDT data.

[0335] b. Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets.

[0336] 2) Downlink small data transmission user plane data volume

[0337] a. Single data packet: indicates the amount of data transmitted by the data packet.

[0338] b.Multi-packet: indicates the amount of data transmitted by each packet.

[0339] 4. Downlink small data transmission signaling information

[0340] 1) Downlink small data transmission signaling auxiliary information

[0341] a. Signaling type: Different signaling corresponds to different signaling radio bearers.

[0342] 2) Downlink small data transmission signaling data volume

[0343] Optionally, the second base station includes a second base station centralized entity user plane and a second base station centralized entity control plane. After the second base station centralized entity receives the second message, the second base station centralized entity user plane sends a downlink data notification message to the second base station centralized entity control plane.

[0344] Optionally, the downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

[0345] In an embodiment of the present application, if the size of the downlink small data transmission data volume includes a downlink signaling indication, it means that the total data of the received inactive downlink small data transmission includes signaling, and a signaling radio bearer needs to be established for it; otherwise, it means that the total data of the received inactive downlink small data transmission includes only user plane data, and only a data radio bearer needs to be established.

[0346] After the second base station receives the Xn RAN Paging message sent by the first base station, the second base station centralized entity user plane (Central Unit-User Plane, CU-UP) sends the inactive downlink small data transmission related information to the second base station centralized entity control plane (Central Unit-Control Plane, CU-CP) through a downlink data notification message to assist the second base station control plane entity in determining whether to initiate an inactive downlink small data transmission process, including but not limited to the following contents:

[0347] 1) Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0348] 2) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0349] 3) Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0350] 4) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0351] 5) Data volume of downlink user plane data: an integer value ranging from 1 to 96000, indicating the data volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0352] Optionally, the second base station includes a second base station centralized entity and a second base station separated entity, wherein the second base station centralized entity sends a first request message and / or a first paging message to the second base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; and the first paging message includes an inactive downlink small data transmission indication.

[0353] Optionally, the first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

[0354] Optionally, in the case where the first request message is a terminal context establishment request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0355] Optionally, in the case where the first request message is a terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

[0356] Optionally, the first paging message includes at least one of the following: an inactive downlink small data transmission indication and a data volume of the downlink small data transmission.

[0357] In an embodiment of the present application, when the second base station centralized entity (CU) sends a UE context establishment request message to the second base station separation entity (DU), if the downlink small data transmission data packet contains downlink data, the request message carries data radio bearer establishment list information; if the downlink small data transmission data packet contains downlink signaling, the request message carries signaling radio bearer establishment list information. Specifically, the UE context establishment request message includes but is not limited to the following information:

[0358] 1) Signaling radio bearer establishment list

[0359] a. Signaling radio bearer establishment project, including: signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumeration value, which can be 0 to 5 (ie, the first interval above), 0 identifies SRB0, 2 indicates SRB2, 3 indicates SRB3 ...;

[0360] b. Radio link layer control protocol RLC bearer configuration for small data transmission;

[0361] 2) Data radio bearer establishment list

[0362] a. Data radio bearer establishment project: Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, which can be 1 to 32 (ie, the second interval above), each number identifies a separate DRB;

[0363] b. RLC bearer configuration for small data transmission.

[0364] After the second base station separation entity (DU) receives the UE context establishment request message sent by the second base station centralized entity (CU), if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID.

[0365] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0366] Similarly, after the second base station separation entity receives the UE context modification request message sent by the second base station concentration entity, the corresponding radio bearer is established according to the data radio bearer and signaling radio bearer indication information therein;

[0367] Among them, if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID;

[0368] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0369] If the second base station separation entity successfully establishes the UE context, a UE context establishment response message is sent to the second base station centralized entity to confirm the UE context establishment, wherein the UE context establishment response message includes the following content according to the establishment of the data radio bearer and the signaling radio bearer:

[0370] 1. Data radio bearer establishment list

[0371] 1) Data wireless bearer establishment project

[0372] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately.

[0373] 2. Signaling radio bearer establishment list

[0374] 1) Signaling radio bearer establishment project

[0375] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0376] 3. List of signaling radio bearer establishment failures

[0377] 1) Signaling radio bearer establishment failure project

[0378] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0379] b. Cause of establishment failure

[0380] 4. Data radio bearer establishment failure list

[0381] 1) Data radio bearer establishment failure items

[0382] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately;

[0383] b. Establish the reason for failure.

[0384] In an embodiment of the present application, when the second base station centralized entity (CU) sends a UE context modification request message (i.e., the above-mentioned terminal context modification request message) to the second base station separated entity (DU), in another optional embodiment, the first base station centralized entity (CU) may also send a UE context modification request message to the first base station separated entity (DU).

[0385] When the second base station centralized entity (CU) sends a UE context modification request message to the second base station separation entity, if downlink data is newly added to the downlink small data transmission data packet (that is, the original downlink small data packet only contains downlink signaling), the request message carries data radio bearer establishment list information.

[0386] If downlink signaling is newly added to the downlink small data transmission data packet (i.e., the original downlink small data packet contains only downlink data), the request message carries the signaling radio bearer establishment list information, and the UE context modification request message includes but is not limited to the following information:

[0387] 1. Signaling radio bearer establishment list

[0388] 1) Signaling radio bearer establishment project

[0389] a. Signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumerated value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, 5 indicates SRB5...;

[0390] b. RLC bearer configuration for small data transmission;

[0391] c. Small data transmission indication establishment: used to indicate the signaling radio bearer of small data transmission SDT.

[0392] 2. Data radio bearer establishment list

[0393] 2) Data wireless bearer establishment project

[0394] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately;

[0395] b. RLC bearer configuration for small data transmission;

[0396] c. Small data transmission indication establishment: used to indicate the data radio bearer of small data transmission SDT.

[0397] After the second base station separation entity (DU) receives the UE context establishment request message sent by the second base station centralized entity (CU), if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID.

[0398] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0399] Similarly, after the second base station separation entity receives the UE context modification request message sent by the second base station concentration entity, the corresponding radio bearer is established according to the data radio bearer and signaling radio bearer indication information therein;

[0400] Among them, if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID;

[0401] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID.

[0402] Specifically, if the second base station separate entity (DU) successfully modifies the UE context, a UE context modification response message is sent to the second base station centralized entity (CU) to confirm the UE context modification, wherein, according to the establishment of the data radio bearer and the signaling radio bearer, the UE context modification response message includes the following content:

[0403] 1. Data radio bearer modification list

[0404] 1) Data radio bearer modification project

[0405] a. Data radio bearer identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately.

[0406] 2. Signaling radio bearer establishment failure list

[0407] 1) Signaling radio bearer establishment failure project

[0408] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, and 5 indicates SRB5.

[0409] b. Reason: indicates the reason for the establishment failure

[0410] 3. Signaling radio bearer establishment list

[0411] 1) Signaling radio bearer establishment project

[0412] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0413] 4. Signaling Radio Bearer Modification List

[0414] 1) Signaling radio bearer modification project

[0415] a. Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0416] In the embodiment of the present application, the paging message carries information related to the inactive downlink small data transmission, which specifically includes but is not limited to the following information:

[0417] 1. Inactive downlink small data transmission indication: enumeration value, "yes" indicates downlink small data transmission, and "no" indicates non-downlink small data transmission.

[0418] 2. Downlink small data transmission data volume: an integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0419] 1) Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission includes downlink signaling.

[0420] a. Downlink signaling data size: integer value, ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer.

[0421] 2) Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes the downlink user plane data.

[0422] a. Downlink user plane data size: integer value, ranging from 1 to 96000, indicating the data size of all downlink user plane data mapped to the inactive small data transmission dedicated bearer.

[0423] It should be noted that the above-mentioned data transmission method with the second base station as the execution subject is the same as Figure 1 The relevant steps in the data transmission method with the first base station centralized entity as the execution subject are the same, so Figure 1 The relevant explanations in the data transmission method shown are also applicable to the data transmission method with the second base station as the execution entity, and will not be repeated here.

[0424] Figure 2 is a partial flow chart a of a method for data transmission provided by an embodiment of the present application, such as Figure 2 As shown in the figure, 5GC represents the core network, the Last Serving gNB is the source base station, that is, the first base station described below, the Receiving gNB is the receiving base station, that is, the second base station described below, and the UE is the user terminal. The specific steps are as follows:

[0425] Step 1: The first base station obtains downlink data and / or downlink signaling (DL data / DL NASsignaling) from the core network, and all received downlink data and / or downlink signaling are mapped to a specific radio bearer for small data transmission, and the total data volume of the downlink data and / or downlink signaling meets the Mobile Terminated Small Data Transmission (MT-SDT) condition;

[0426] In addition, the first base station can obtain information such as the data type of signaling and / or data mapped to a specific wireless bearer for small data transmission from the core network; the first base station can judge based on the data and related information sent by the core network that it can send the received data and signaling to the inactive terminal through the inactive downlink small data transmission process.

[0427] The data and information obtained by the first base station from the core network include but are not limited to the following:

[0428] Downlink small data transmission user plane data information

[0429] Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0430] A single data packet indicates no subsequent MT-SDT data.

[0431] Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets

[0432] Downlink small data transmission user plane data volume

[0433] Single data packet: indicates the amount of data transmitted by the data packet

[0434] Multi-packet: indicates the amount of data transmitted by each packet

[0435] Downlink small data transmission signaling information

[0436] Downlink small data transmission signaling auxiliary information

[0437] Signaling type: Different signaling corresponds to different signaling radio bearers

[0438] Downlink small data transmission signaling data volume

[0439] Step 2: The first base station sends the inactive downlink small data transmission (MT-SDT) related information to other base stations (including the second base station) in the radio notification area (RAN Notification area, RNA) through the radio access network (RAN) paging message (Xn RAN Paging) of the Xn interface. The MT-SDT information includes but is not limited to the following information:

[0440] Downlink small data transmission indication: enumeration value, "yes" indicates downlink small data transmission, "no" indicates non-downlink small data transmission;

[0441] Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0442] Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0443] Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0444] Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0445] Downlink user plane data volume: integer value ranging from 1 to 96000, indicating the volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer;

[0446] Among them, if the size of the downlink small data transmission data volume includes a downlink signaling indication, it means that the total data of the received inactive downlink small data transmission contains signaling, and a signaling wireless bearer needs to be established for it. Otherwise, it means that the total data of the received inactive downlink small data transmission only contains user plane data, and only a data wireless bearer needs to be established.

[0447] Step 3: If Figure 5 As shown, after the second base station receives the Xn RAN Paging message sent by the first base station, the second base station centralized entity user plane (Central Unit-User Plane, CU-UP) sends the inactive downlink small data transmission related information to the second base station centralized entity control plane (Central Unit-Control Plane, CU-CP) through a downlink data notification message (DL datanotification) to assist the second base station control plane entity in determining whether to initiate an inactive downlink small data transmission process, including but not limited to the following contents:

[0448] Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0449] Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0450] Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0451] Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0452] Downlink user plane data volume: integer value ranging from 1 to 96000, indicating the volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer;

[0453] Step 4: Figure 3 As shown, the second base station centralized entity (CU) sends a UE context setup request message (UE context setup request) to the second base station separation entity (DU). If the downlink small data transmission data packet contains downlink data, the request message carries data radio bearer establishment list information; if the downlink small data transmission data packet contains downlink signaling, the request message carries signaling radio bearer establishment list information. Specifically, the UE context setup request message includes but is not limited to the following information:

[0454] Signaling Radio Bearer Setup List

[0455] Signaling Radio Bearer Establishment Project

[0456] Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0457] RLC bearer configuration for small data transmission

[0458] Data Radio Bearer Establishment List

[0459] Data Radio Bearer Establishment Project

[0460] Data Radio Bearer Identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately

[0461] RLC bearer configuration for small data transmission

[0462] Step 5: After the second base station separation entity (DU) receives the UE context establishment request message sent by the second base station centralized entity (CU), if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration, and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID;

[0463] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration, and the second base station separation entity (DU) supports the configuration, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID;

[0464] Step 6: Figure 3 As shown, if the second base station separation entity successfully establishes the UE context, a UE context establishment response message (UE context setup response) is sent to the second base station centralized entity to confirm the UE context establishment, wherein, according to the establishment of the data radio bearer and the signaling radio bearer, the UE context establishment response message includes the following content:

[0465] Data Radio Bearer Establishment List

[0466] Data Radio Bearer Establishment Project

[0467] Data Radio Bearer Identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately

[0468] Signaling Radio Bearer Setup List

[0469] Signaling Radio Bearer Establishment Project

[0470] Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0471] Signaling radio bearer establishment failure list

[0472] Signaling radio bearer establishment failure item

[0473] Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0474] Cause of failure to establish

[0475] Data radio bearer establishment failure list

[0476] Data radio bearer establishment failure item

[0477] Data Radio Bearer Identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately

[0478] Cause of failure to establish

[0479] Steps 4 to 6 can be replaced by steps 4-1 to 6-1:

[0480] Step 4-1: If Figure 4 As shown, the second base station centralized entity sends a UE context modification request message (UE context modification request) to the second base station separation entity. If downlink data is newly added to the downlink small data transmission data packet (that is, there is only downlink signaling in the original downlink small data packet), the request message carries data radio bearer establishment list information;

[0481] If downlink signaling is newly added to the downlink small data transmission data packet (that is, the original downlink small data packet contains only downlink data), the request message carries signaling radio bearer establishment list information;

[0482] The UE context establishment request message includes but is not limited to the following information:

[0483] Signaling Radio Bearer Setup List

[0484] Signaling Radio Bearer Establishment Project

[0485] Signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, 5 indicates SRB5...

[0486] RLC bearer configuration for small data transmission

[0487] Small data transmission indication establishment: signaling radio bearer used to indicate small data transmission SDT

[0488] Data Radio Bearer Establishment List

[0489] Data Radio Bearer Establishment Project

[0490] Data Radio Bearer Identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately

[0491] RLC bearer configuration for small data transmission

[0492] Small data transmission indication establishment: data radio bearer used to indicate small data transmission SDT

[0493] Step 5-1: After receiving the UE context modification request message sent by the second base station centralized entity, the second base station separation entity establishes a corresponding radio bearer according to the data radio bearer and signaling radio bearer indication information therein;

[0494] Among them, if the signaling radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission signaling radio bearer SDT SRB indicated by the signaling radio bearer identifier SRB ID;

[0495] Similarly, if the data radio bearer establishment list includes a small data transmission RLC bearer configuration and the second base station separation entity supports it, the configuration is used for data packet transmission of the small data transmission data radio bearer SDT DRB indicated by the data radio bearer identifier DRB ID;

[0496] Step 6-1: If Figure 4 As shown, if the second base station separation entity successfully modifies the UE context, a UE context modification response message (UE context modification response) is sent to the second base station centralized entity to confirm the UE context modification, wherein, according to the establishment of the data radio bearer and the signaling radio bearer, the UE context modification response message includes the following content:

[0497] Data Radio Bearer Modification List

[0498] Data Radio Bearer Modification Project

[0499] Data Radio Bearer Identifier: used to identify the data radio bearer DRB; enumeration value, can be 1 to 32, each number identifies a DRB separately

[0500] Signaling radio bearer establishment failure list

[0501] Signaling radio bearer establishment failure item

[0502] Signaling radio bearer identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3, 4 indicates SRB4, 5 indicates SRB5

[0503] Reason: Indicates the reason for the establishment failure

[0504] Signaling Radio Bearer Setup List

[0505] Signaling Radio Bearer Establishment Project

[0506] Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0507] Signaling Radio Bearer Modification List

[0508] Signaling Radio Bearer Modification Project

[0509] Signaling Radio Bearer Identifier: used to identify the signaling radio bearer SRB; enumeration value, can be 0 to 5, 0 indicates SRB0, 2 indicates SRB2, 3 indicates SRB3...

[0510] Step 7: Figure 5 As shown, the second base station determines and decides to trigger the inactive downlink small data transmission process in combination with the inactive downlink small data transmission information sent by the first base station through Xn RAN Paging. Subsequently, the second base station centralized entity control plane (CU-CP) sends a paging message (Paging) to the second base station separation entity (DU), which carries inactive downlink small data transmission related information, which specifically includes but is not limited to the following information:

[0511] Inactive downlink small data transmission indication: enumeration value, "yes" indicates downlink small data transmission, "no" indicates non-downlink small data transmission;

[0512] Downlink small data transmission data volume: integer value ranging from 1 to 96000, indicating the total data volume of all downlink user plane data and downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0513] Downlink signaling indication: indicates that the total data of the inactive downlink small data transmission contains downlink signaling;

[0514] Downlink signaling data size: integer value ranging from 1 to 96000, indicating the total data size of all downlink signaling mapped to the inactive small data transmission dedicated bearer;

[0515] Downlink user plane data indication: indicates that the total data of the inactive downlink small data transmission includes downlink user plane data;

[0516] Downlink user plane data volume: integer value ranging from 1 to 96000, indicating the volume of all downlink user plane data mapped to the inactive small data transmission dedicated bearer;

[0517] Step 8: When the paging message received by the second base station separation entity includes inactive downlink small data transmission information, and the second base station separation entity supports the information, the inactive downlink small data transmission paging message (Uu Paging) is sent to the inactive terminal using the information, and the paging message includes an inactive downlink small data transmission indication;

[0518] Step 9: After receiving the paging message sent by the second base station, if the inactive state small data transmission condition is met, the inactive state terminal sends an RRC resume request message (RRC Resume Ruquest) to the second base station, in which the resumption reason carried is the inactive state downlink small data transmission indication;

[0519] Step 10: After receiving the request message, the second base station sends a UE context acquisition request message (Retrieve UE Context Request) to the first base station, where it is necessary to indicate that the request is initiated by an inactive downlink small data transmission. The message includes but is not limited to the following information (the following two options are available):

[0520] Option 1: Inactive downlink small data transmission indication: enumeration type, "true" indicates downlink small data transmission, "false" indicates no downlink small data transmission.

[0521] This indication is different from the small data transmission indication. The small data transmission indication is for the inactive uplink small data transmission indication, while this indication is for the inactive downlink small data transmission.

[0522] Option 2: small data transmission indication, enumeration type, "true" indicates downlink small data transmission, "false" indicates no downlink small data transmission; in this case, no small data transmission auxiliary information is included to indicate that the transmission is inactive downlink small data transmission.

[0523] Step 11: The first base station determines whether to agree to the request of the second base station based on the downlink data and signaling related information sent by the core network; if agreed, a UE context response message (Retrieve UE ContextResponse) is fed back to the second base station, which carries data and signaling related information of the inactive downlink small data transmission, including but not limited to the following information:

[0524] Downlink small data transmission user plane data information

[0525] Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0526] A single data packet indicates no subsequent MT-SDT data.

[0527] Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets

[0528] Downlink small data transmission user plane data volume

[0529] Single data packet: indicates the amount of data transmitted by the data packet

[0530] Multi-packet: indicates the amount of data transmitted by each packet

[0531] Downlink small data transmission signaling information

[0532] Downlink small data transmission signaling auxiliary information

[0533] Signaling type: Different signaling corresponds to different signaling radio bearers

[0534] Downlink small data transmission signaling data volume

[0535] If not agreed, part of the UE context message is fed back to the second base station, which carries data and signaling information related to the transmission of inactive downlink small data, including but not limited to the following information:

[0536] Downlink small data transmission user plane data information

[0537] Downlink small data transmission user plane data auxiliary information: enumeration type, including "single data packet" and "multiple data packets"

[0538] A single data packet indicates no subsequent MT-SDT data.

[0539] Multiple data packets indicate that there is subsequent MT-SDT data: it can indicate the number of subsequent data packets

[0540] Downlink small data transmission user plane data volume

[0541] Single data packet: indicates the amount of data transmitted by the data packet

[0542] Multi-packet: indicates the amount of data transmitted by each packet

[0543] Downlink small data transmission signaling information

[0544] Downlink small data transmission signaling auxiliary information

[0545] Signaling type: Different signaling corresponds to different signaling radio bearers

[0546] Downlink small data transmission signaling data volume.

[0547] An embodiment of the present application also provides a data transmission device, including: a first receiving module, used to receive a first message sent by a core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of upcoming downlink data; a first sending module, used to send a first request message and / or a first paging message to a first base station separation entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0548] It should be noted that the above data transmission device is used to execute Figure 1 The data transmission method shown in the figure is performed by the first base station centralized entity. Figure 1 The relevant explanations in the data transmission method shown are also applicable to the data transmission device, which will not be repeated here.

[0549] An embodiment of the present application also provides another data transmission device, including: a second receiving module, used to receive a first request message and / or a first paging message sent by a first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

[0550] It should be noted that the above-mentioned data transmission device is used to execute the data transmission method with the first base station separation entity as the execution subject, so Figure 1 The relevant explanations in the data transmission method shown are also applicable to the data transmission device, which will not be repeated here.

[0551] The embodiment of the present application also provides another data transmission device, including: a third receiving module, used to receive a second message sent by a first base station centralized entity, the second message including at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to an inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to an inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to an inactive downlink small data transmission dedicated bearer.

[0552] It should be noted that the above-mentioned data transmission device is used to execute the data transmission method with the second base station as the execution subject, so Figure 1 The relevant explanations in the data transmission method shown are also applicable to the data transmission device, which will not be repeated here.

[0553] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0554] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0555] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0556] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0557] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0558] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0559] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for data transmission, characterized in that: include: The first base station centralized entity receives a first message sent by the core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of downlink data to be arrived; The first base station centralized entity sends a first request message and / or a first paging message to the first base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

2. The method according to claim 1, characterized in that The first downlink signaling indication includes at least one of the following: a downlink signaling indication and a downlink signaling size indication, wherein the downlink signaling indication is used to indicate that the first base station receives downlink signaling sent by the core network, and the downlink signaling size indication is used to indicate the size of the downlink signaling sent by the core network received by the first base station.

3. The method according to claim 1, characterized in that The first indication of downlink user plane data includes at least one of the following: a downlink user plane data indication, a downlink user plane data size indication, wherein the downlink user plane data indication is used to indicate the first base station to receive user plane data sent by the core network, and the downlink user plane data size indication is used to indicate the size of user plane data sent by the core network to be received by the first base station.

4. The method according to claim 1, characterized in that: The first indication of the upcoming downlink data includes at least one of the following: an indication of the upcoming downlink user plane data, an indication of the upcoming downlink signaling, wherein the indication of the upcoming downlink user plane data is used to indicate that the core network is about to send downlink user plane data to the first base station, and the indication of the upcoming downlink signaling is used to indicate that the core network is about to send downlink signaling to the first base station.

5. The method according to claim 1, characterized in that The first base station centralized entity sends a second message to the second base station, and the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to the inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to the inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to the inactive downlink small data transmission dedicated bearer.

6. The method according to claim 5, characterized in that In a case where the downlink small data transmission data amount includes the downlink signaling indication, determining to establish a signaling radio bearer; In a case where the data volume of the downlink small data transmission includes the downlink user plane data indication, it is determined to establish a data radio bearer.

7. The method according to claim 1, characterized in that The first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

8. The method according to claim 7, characterized in that In the case where the first request message is a request message for establishing the terminal context, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

9. The method according to claim 8, characterized in that The signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

10. The method according to claim 8, characterized in that The data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

11. The method according to claim 7, characterized in that In the case where the first request message is the terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

12. The method according to claim 11, characterized in that The signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

13. The method according to claim 11, characterized in that The data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

14. The method according to claim 9 or 12, characterized in that: The value range of the signaling radio bearer identifier is a first interval, the first value in the first interval represents a signaling radio bearer used to transmit application layer measurement reporting information, and the second value in the first interval represents a signaling radio bearer used to transmit experience quality information to a secondary node, wherein the first value is less than the second value.

15. The method according to claim 10 or 13, characterized in that: The value range of the data radio bearer identifier is a second interval.

16. The method according to claim 9 or 12, characterized in that: After the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the signaling wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the signaling wireless bearer for the inactive downlink small data transmission indicated by the signaling wireless bearer identifier.

17. The method according to claim 10 or 13, characterized in that: After the first base station separation entity receives the first request message sent by the first base station centralized entity, and when the wireless link layer control bearer configuration is included in the data wireless bearer establishment list and the first base station separation entity supports the wireless link layer control bearer configuration, the wireless link layer control bearer configuration is used for the data packet transmission of the data wireless bearer for the inactive downlink small data transmission indicated by the data wireless bearer identifier.

18. The method according to claim 7, characterized in that When the first request message is the terminal context establishment request message and the first base station separation entity successfully establishes the terminal context according to the first request message, the first base station centralized entity receives the terminal context establishment response message fed back by the first base station separation entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

19. The method according to claim 18, characterized in that The terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

20. The method according to claim 19, characterized in that The data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

21. The method according to claim 19, characterized in that The signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

22. The method according to claim 19, characterized in that The signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one of the signaling radio bearer establishment failure items includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

23. The method according to claim 19, characterized in that The data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, at least one of the data radio bearer establishment failure items includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

24. The method according to claim 7, characterized in that When the first request message is the terminal context modification request message and the first base station separation entity successfully modifies the terminal context according to the first request message, the first base station centralized entity receives the terminal context modification response message fed back by the first base station separation entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

25. The method according to claim 24, characterized in that The terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

26. The method according to claim 25, characterized in that The data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include data radio bearer identifiers.

27. The method according to claim 25, characterized in that The signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one of the signaling radio bearer establishment failure items includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

28. The method according to claim 25, characterized in that The signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

29. The method according to claim 25, characterized in that The signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification item includes a signaling radio bearer identifier.

30. The method according to claim 1, characterized in that The first paging message includes at least one of the following: an inactive downlink small data transmission indication and a downlink small data transmission data volume.

31. The method according to claim 30, characterized in that When the first paging message received by the first base station separation entity includes an inactive downlink small data transmission indication and the first base station separation entity supports the inactive downlink small data transmission indication, the inactive downlink small data transmission indication is sent to the user terminal through the first base station separation entity.

32. The method according to claim 1, characterized in that The method also includes: the first base station centralized entity receives a user terminal context acquisition request message sent by the second base station, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

33. The method according to claim 32, characterized in that The method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the first base station centralized entity sends a user terminal context response message to the second base station, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

34. The method according to claim 32, characterized in that The method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the first base station centralized entity sends a partial user terminal context message to the second base station, wherein the partial user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

35. The method according to claim 33 or 34, characterized in that The inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

36. The method according to claim 34, characterized in that The inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

37. The method according to claim 1, characterized in that The first message further includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

38. The method according to claim 37, characterized in that The inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

39. The method according to claim 37, characterized in that The inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

40. The method according to claim 5, characterized in that The first base station centralized entity includes a first base station centralized entity user plane and a first base station centralized entity control plane. After the first base station centralized entity receives the second message, the first base station centralized entity user plane sends a downlink data notification message to the first base station centralized entity control plane.

41. The method according to claim 40, characterized in that The downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

42. A method for data transmission, characterized in that: include: The first base station separation entity receives a first request message and / or a first paging message sent by the first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; and the first paging message includes an inactive downlink small data transmission indication.

43. The method according to claim 42, characterized in that The first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

44. The method according to claim 43, characterized in that In the case where the first request message is a request message for establishing the terminal context, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

45. The method according to claim 44, characterized in that The signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

46. ​​The method according to claim 44, characterized in that The data radio bearer establishment item includes at least one of a data radio bearer identifier and a radio link layer control bearer configuration for inactive small data transmission.

47. The method according to claim 43, characterized in that In the case where the first request message is the terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

48. The method according to claim 47, characterized in that The signaling radio bearer establishment item includes at least one of a signaling radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

49. The method according to claim 47, characterized in that The data radio bearer establishment item includes at least one of a data radio bearer identifier, a radio link layer control bearer configuration for inactive small data transmission, and an inactive downlink small data transmission indication.

50. The method of claim 43, wherein: When the first request message is the terminal context establishment request message and the first base station separation entity successfully establishes the terminal context according to the first request message, the first base station separation entity feeds back a terminal context establishment response message to the first base station centralized entity, wherein the terminal context establishment response message includes the result of the requested data radio bearer and / or signaling radio bearer.

51. The method according to claim 50, characterized in that The terminal context establishment response message includes at least one of a data radio bearer establishment list, a signaling radio bearer establishment list, a signaling radio bearer establishment failure list, and a data radio bearer establishment failure list.

52. The method according to claim 51, characterized in that The data radio bearer establishment list includes one or more data radio bearer establishment items, and the data radio bearer establishment items include data radio bearer identifiers.

53. The method according to claim 51, characterized in that The signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

54. The method according to claim 51, characterized in that The signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one of the signaling radio bearer establishment failure items includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason, wherein the signaling radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

55. The method according to claim 51, characterized in that The data radio bearer establishment failure list includes one or more data radio bearer establishment failure items, at least one of the data radio bearer establishment failure items includes a data radio bearer identifier and a data radio bearer establishment failure reason, wherein the data radio bearer establishment failure reason includes an inability to support inactive downlink small data transmission.

56. The method of claim 43, wherein: When the first request message is the terminal context modification request message and the first base station separation entity successfully modifies the terminal context according to the first request message, the first base station separation entity feeds back a terminal context modification response message to the first base station centralized entity, wherein the terminal context modification response message includes the result of the requested data radio bearer and / or signaling radio bearer.

57. The method according to claim 56, characterized in that The terminal context modification response message includes at least one of a data radio bearer modification list, a signaling radio bearer establishment failure list, a signaling radio bearer establishment list, and a signaling radio bearer modification list.

58. The method according to claim 57, characterized in that The data radio bearer modification list includes one or more data radio bearer modification items, and the data radio bearer modification items include data radio bearer identifiers.

59. The method according to claim 57, characterized in that The signaling radio bearer establishment failure list includes one or more signaling radio bearer establishment failure items, and at least one of the signaling radio bearer establishment failure items includes a signaling radio bearer identifier and a signaling radio bearer establishment failure reason.

60. The method of claim 57, wherein: The signaling radio bearer establishment list includes one or more signaling radio bearer establishment items, and the signaling radio bearer establishment items include signaling radio bearer identifiers.

61. The method according to claim 57, characterized in that The signaling radio bearer modification list includes one or more signaling radio bearer modification items, and the signaling radio bearer modification item includes a signaling radio bearer identifier.

62. The method of claim 42, wherein: The first paging message includes at least one of the following: an inactive downlink small data transmission indication and a downlink small data transmission data volume.

63. A method for data transmission, characterized in that: include: The second base station receives a second message sent by the centralized entity of the first base station, wherein the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to the inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to the inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to the inactive downlink small data transmission dedicated bearer.

64. The method according to claim 63, characterized in that In a case where the downlink small data transmission data amount includes the downlink signaling indication, determining to establish a signaling radio bearer; In a case where the data volume of the downlink small data transmission includes the downlink user plane data indication, it is determined to establish a data radio bearer.

65. The method according to claim 63, characterized in that The method further comprises: The second base station receives a radio resource control restoration request message sent by a user terminal, wherein a restoration reason of the radio resource control restoration request message is an inactive downlink small data transmission indication.

66. The method according to claim 63, characterized in that The method further comprises: The second base station sends a user terminal context acquisition request message to the first base station centralized entity, wherein the user terminal context acquisition request message includes at least one of the following: an inactive downlink small data transmission indication and a small data transmission indication, the inactive downlink small data transmission indication is an indication for inactive downlink small data transmission, and the small data transmission indication is an indication for inactive uplink small data transmission.

67. The method according to claim 66, characterized in that The method also includes: when the first base station centralized entity agrees to the user terminal context acquisition request message, the second base station receives a user terminal context response message sent by the first base station centralized entity, wherein the user terminal context response message includes at least one of the following: inactive downlink small data transmission user plane data information, downlink small data transmission signaling information, and other terminal context information.

68. The method according to claim 66, characterized in that The method also includes: when the first base station centralized entity does not agree to the user terminal context acquisition request message, the second base station receives part of the user terminal context message sent by the first base station centralized entity, wherein the part of the user terminal context message includes at least one of the following: inactive downlink small data transmission user plane data information and inactive downlink small data transmission signaling information.

69. The method according to claim 67 or 68, characterized in that The inactive downlink small data transmission user plane data information includes at least one of the following: inactive downlink small data transmission user plane data auxiliary information and inactive downlink small data transmission user plane data volume, wherein the inactive downlink small data transmission user plane data auxiliary information includes first information indicating that there is no subsequent downlink small data transmission data and / or second information indicating that there is subsequent downlink small data transmission data, and the inactive downlink small data transmission user plane data volume includes a first data volume indicating the size of data transmitted by a single data packet and / or a second data volume indicating the size of data transmitted by each data packet in multiple data packets.

70. The method according to claim 67 or 68, characterized in that The inactive downlink small data transmission signaling information includes at least one of the following: inactive downlink small data transmission signaling auxiliary information and inactive downlink small data transmission signaling data volume, wherein the inactive downlink small data transmission signaling auxiliary information includes a signaling type.

71. The method of claim 63, wherein: The second base station includes a second base station centralized entity user plane and a second base station centralized entity control plane. After the second base station centralized entity receives the second message, the second base station centralized entity user plane sends a downlink data notification message to the second base station centralized entity control plane.

72. The method according to claim 71, characterized in that The downlink data notification message includes the data volume size of the inactive downlink small data transmission, wherein the data volume size of the inactive downlink small data transmission includes at least one of a downlink signaling indication and a downlink user plane data indication, the downlink signaling indication includes the data volume size of the downlink signaling, and the downlink user plane data indication includes the data volume size of the downlink user plane data.

73. The method according to claim 71, characterized in that The second base station includes a second base station centralized entity and a second base station separated entity, wherein: The second base station centralized entity sends a first request message and / or a first paging message to the second base station separated entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

74. The method according to claim 73, characterized in that The first request message is at least one of a terminal context establishment request message and a terminal context modification request message.

75. The method according to claim 74, characterized in that In the case where the first request message is a request message for establishing the terminal context, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

76. The method of claim 74, wherein: In the case where the first request message is the terminal context modification request message, the first request message includes at least one of the following: a signaling radio bearer establishment list and a data radio bearer establishment list, wherein the signaling radio bearer establishment list contains one or more signaling radio bearer establishment items, and the data radio bearer establishment list contains one or more data radio bearer establishment items.

77. The method according to claim 1, characterized in that The first paging message includes at least one of the following: an inactive downlink small data transmission indication and a downlink small data transmission data volume.

78. A data transmission device, characterized in that: include: A first receiving module is configured to receive a first message sent by a core network, wherein the first message includes at least one of the following: a first indication of downlink signaling, a first indication of downlink user plane data, and a first indication of downlink data to be arrived; The first sending module is used to send a first request message and / or a first paging message to the first base station separation entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

79. A data transmission device, characterized in that: include: The second receiving module is used to receive a first request message and / or a first paging message sent by a first base station centralized entity, wherein the first request message includes at least one of the following: small data transmission signaling radio bearer configuration, small data transmission data radio bearer configuration, signaling radio bearer configuration, data radio bearer configuration; the first paging message includes an inactive downlink small data transmission indication.

80. A data transmission device, characterized in that: include: The third receiving module is used to receive a second message sent by the first base station centralized entity, wherein the second message includes at least one of the following: a downlink small data transmission indication, a downlink small data transmission data volume, a downlink signaling indication, a downlink signaling data volume indication, a downlink user plane data indication, and a downlink user plane data volume indication, wherein the downlink small data transmission indication is used to characterize whether it is an inactive downlink small data transmission; the downlink small data transmission data volume indication is used to characterize the total data volume of all downlink user plane data and downlink signaling mapped to the inactive downlink small data dedicated bearer; the downlink signaling indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink signaling; the downlink signaling data volume indication is used to characterize the total data volume of all downlink signaling mapped to the inactive downlink small data transmission dedicated bearer; the downlink user plane data indication is used to characterize that the total data of the inactive downlink small data transmission includes downlink user plane data; the downlink user plane data volume indication is used to characterize the data volume of all downlink user plane data mapped to the inactive downlink small data transmission dedicated bearer.

Images