CN110536477B

CN110536477B - Connection method, device, network equipment and storage medium

Info

Publication number: CN110536477B
Application number: CN201910267440.6A
Authority: CN
Inventors: 杨立; 马子江; 方建民; 黄河
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2019-04-03
Filing date: 2019-04-03
Publication date: 2023-11-14
Anticipated expiration: 2039-04-03
Also published as: WO2020200261A1; CN110536477A

Abstract

The application provides a connection method, a device, network equipment and a storage medium. The connection method comprises the following steps: sending a first indication message to a target auxiliary base station, wherein the first indication message comprises first indication information for executing specified operation on auxiliary connection between the target auxiliary base station and a target terminal, and the specified operation comprises establishment, addition, modification, deletion or release of the auxiliary connection; and receiving a first response message from the target auxiliary base station, wherein the first response message comprises first result information corresponding to the first indication information. The embodiment of the application can directly instruct the target auxiliary base station to execute the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal, thereby being beneficial to improving the flexibility of the multi-connection operation.

Description

Connection method, device, network equipment and storage medium

Technical Field

The present application relates to the field of communications, and in particular, to a connection method, a device, a network device, and a storage medium.

Background

In a 3GPP fourth generation land-based (4 g) or LTE (Long Term Evolution, E long term evolution) cellular mobile communication system, the method comprises: the 4G core network EPC (Evolved Packet Core ) and RAN (Radio Access Network, radio access network). Wherein the 4G EPC comprises: MME (Mobility Management Entity, mobility management entity node), SGW (Serving Gateway node), PGW (PDN Gateway node) and other basic network element nodes. The 4G RAN includes: interfaces between an eNB (evolved Node B) and a number of base stations.

In a fifth Generation land-based 5G cellular mobile communication system after 4G, a 5GC (5 Generation Core, fifth Generation Core network) and NG-RAN (Next Generation Radio Access Network ) are included. Wherein 5GC includes: AMF (Access Mobility Function ) node, SMF (Session Management Function, session management function) node, and UPF (User Plane Function ) node. The NG-RAN at least comprises: base stations of two different RAT (Radio Access Technology ) system types, namely: and continuously enhancing the evolved ng-eNB and the gNB base station with a brand new physical layer air interface design based on the 4G eNB. The NG-RAN also includes interfaces between the base stations and the associated network element entities. The ng-eNB air interface still supports E-UTRA (evolved Universal Terrestrial Radio Access ) RAT system, and the gNB air interface supports NR (New Radio) RAT system.

Under the condition that the UE is connected with a plurality of base stations of an access network for data transmission, the interface between a main base station and a core network and the Xn interface between the main base station and an auxiliary base station are required to be relied on for the interaction of various double multi-connection operation related information. However, in some cases, the Xn interface connection is not fixed and has relatively low robustness, which easily causes unstable multi-connection or cannot be configured to operate.

Disclosure of Invention

In order to solve at least one of the above technical problems, the embodiments of the present application provide the following solutions.

The embodiment of the application provides a connection method, which comprises the following steps:

sending a first indication message to a target auxiliary base station, wherein the first indication message comprises first indication information for executing specified operation on auxiliary connection between the target auxiliary base station and a target terminal, and the specified operation comprises establishment, addition, modification, deletion or release of the auxiliary connection;

and receiving a first response message from the target auxiliary base station, wherein the first response message comprises first result information corresponding to the first indication information.

receiving a first indication message from a core network element, wherein the first indication message comprises first indication information for executing appointed operation on an auxiliary connection between a target auxiliary base station and a target terminal, and the appointed operation comprises establishment, addition, modification, deletion or release of the auxiliary connection;

executing the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal;

and sending a first response message to the core network element, wherein the first response message comprises first result information corresponding to the first indication message.

An embodiment of the present application provides a connection device, including:

the first sending module is used for sending a first indication message to a target auxiliary base station, wherein the first indication message comprises first indication information for executing specified operation on auxiliary connection between the target auxiliary base station and a target terminal, and the specified operation comprises establishment, addition, modification or deletion;

the first receiving module is used for receiving a first response message from the target auxiliary base station, wherein the first response message comprises first result information corresponding to the first indication information.

a fifth receiving module, configured to receive a first indication message from a core network element, where the first indication message includes first indication information that performs a specified operation on an auxiliary connection between a target auxiliary base station and a target terminal, where the specified operation includes establishment, addition, modification, or deletion;

an execution module, configured to execute the specified operation on an auxiliary connection between the target auxiliary base station and the target terminal;

and a fifth sending module, configured to send a first response message to the core network element, where the first response message includes first result information corresponding to the first indication message.

An embodiment of the present application provides a network device, including: a processor and a memory;

the memory is used for storing instructions;

the processor is configured to read the instructions to perform the method according to any of the embodiments of the application.

An embodiment of the present application provides a storage medium storing a computer program that, when executed by a processor, implements a method according to any one of the embodiments of the present application.

The embodiment of the application can directly instruct the target auxiliary base station to execute the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal, thereby being beneficial to improving the flexibility of the multi-connection operation.

With respect to the above embodiments and other aspects of the application and implementations thereof, further description is provided in the accompanying drawings, detailed description and claims.

Drawings

Fig. 1 is a diagram of an architecture of an aggregated NG-RAN base station.

Fig. 2 is a schematic diagram of heterogeneous networks deployed by macro and micro cells of different RAT systems.

Fig. 3 is a schematic diagram of a MN hosting UE dual connectivity operation.

Fig. 4a and 4b are schematic diagrams of a UE in dual connectivity mode.

Fig. 5a and 5b are schematic diagrams of satellite base station serving cell coverage changes.

Fig. 6 is a schematic diagram of satellite base station feeder link establishment maintenance.

Fig. 7 is a flowchart of a connection method according to an embodiment of the application.

Fig. 8 is a flowchart of a connection method according to another embodiment of the present application.

Fig. 9 is a flowchart of a connection method according to another embodiment of the present application.

Fig. 10 is a flowchart of a connection method according to another embodiment of the present application.

Fig. 11 is a flowchart of a connection method according to another embodiment of the present application.

Fig. 12 is a flowchart of a connection method according to another embodiment of the present application.

Fig. 13 is a diagram of a dual connectivity data transmission operation performed by a 5GC master UE.

Fig. 14a is a schematic diagram of an application example of dual connectivity of a UE with a satellite base station and a ground station.

Fig. 14b is a schematic diagram of MN initiated addition procedure.

Fig. 15a is a schematic diagram of an application example of dual connectivity of a UE with a satellite base station and a ground station.

Fig. 15b is a schematic diagram of MN initiated modification procedure.

Fig. 16a is a schematic diagram of an application example of dual connectivity of a UE with a satellite base station and a ground station.

Fig. 16b is a schematic diagram of MN initiated delete procedure.

Fig. 17a is a schematic diagram of an application example of dual connectivity of a UE with a satellite base station and a ground station.

Fig. 17b is a schematic diagram of a 5GC initiated addition procedure.

Fig. 18a is a schematic diagram of an application example of dual connectivity of a UE with a satellite base station and a ground station.

Fig. 18b is a schematic diagram of SN initiated modification procedure.

Fig. 19 is a schematic structural diagram of a connection device according to an embodiment of the application.

Fig. 20 is a schematic structural diagram of a connection device according to another embodiment of the present application.

Fig. 21 is a schematic structural diagram of a connection device according to another embodiment of the present application.

Fig. 22 is a schematic structural diagram of a connection device according to another embodiment of the present application.

Fig. 23 is a schematic structural diagram of a network device according to an embodiment of the present application.

Fig. 24 is a schematic structural diagram of a network device according to an embodiment of the present application.

Fig. 25 is a schematic structural diagram of a communication system according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in detail hereinafter with reference to the accompanying drawings. It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be arbitrarily combined with each other.

Fig. 1 is a diagram of an architecture of an Aggregated NG-RAN base station. As shown in fig. 1, numerous NG-RAN base stations (e.g., gnbs or NG-enbs, etc.) are interconnected by a standardized NG interface and 5 GC. For example, including NG-C control plane (signaling) connections and NG-U user plane (user data) connections. The NG-RAN base stations (gNB or NG-eNB) are connected with each other through an Xn interface (comprising an Xn-C control plane connection and an Xn-U user plane connection). The control plane connection of the interface is used for transmitting control signaling messages between network element nodes, such as NGAP (Next Generation Application Protocol ), xnAP protocol flow messages. The user plane connection is used for transmitting user traffic data (packets/frames/blocks) etc. NGAP, xnAP is NG-C, xn-C control plane logical network application layer protocol, respectively, and transmits control signaling flow messages on the corresponding interface based on lower layer bearer transport (SCTP connection). NG-U, xn-U user plane interface user traffic data, user traffic data on the corresponding interface is transmitted based on lower layer bearer transport (e.g., GTP-U tunnel). The NG-RAN base station and the served terminal UE are connected to each other via a Uu air interface (i.e. a radio air interface). The Uu air interface includes a plurality of air interface control plane signaling radio bearers SRB (Signaling Radio Bearer) and a plurality of air interface user plane data radio bearers DRB (Data Radio Bearer).

In conventional land-based terrestrial cellular mobile systems, the deployment of various base stations, once the site is determined, is relatively stationary and stationary with respect to the physical location of a particular longitude and latitude of the ground. The configuration and provisioning of radio coverage/capacity (Coverage and Capacity) of the air-interface Uu Serving Cell (Serving Cell) provided by each NG-RAN base station, as well as NG, xn interface instances connecting these NG-RAN neighbor base stations, etc., are also fixed relative to the physical location. Such as: the bearing transmission of interfaces such as NG, xn and the like is realized mostly by a fixed network transmission mode such as broadband optical fiber and the like, so that the robustness, the time delay, the signaling and the data transmission efficiency and the like of the network side interface connection are good. This relatively stationary, fixed land-based terrestrial cellular mobile network facilitates the planning deployment and RRM (Radio Resource Management ) of the operator. As shown in fig. 2, in a heterogeneous large network where macro and micro serving cells are mixed and deployed, there may exist various types of base stations with different RAT systems, different carrier frequency points and working bandwidths, and different wireless coverage capabilities, for example: network element nodes such as 4G legacy eNB, 5G gNB, ng-eNB, WLAN AP (Wireless Local Area Networks Access Point, wireless local area network access point) and the like can interoperate with each other.

The 5G system supports the terminal UE in SC (Single Connectivity, single connection) and DC/MC (Dual/Multiple Connectivity, dual/multiple connection) modes of operation. Wherein, the multi-connection is the logical dimension expansion of the dual-connection, and the dual-connection DC is mainly described below. In the SC single connection mode of operation, the UE has only one signaling or data transmission channel on the air interface Uu and the network side, referred to as a radio link RL (Radio Link). In the DC/MC dual/multi-connection mode, the UE has two or more signaling or data transmission channels, i.e., multiple relatively independent RLs, on the air interface and network side. Multiple air-interface signaling radio bearers SRBs and data radio bearers DRBs can be configured and used on the above-described dual/multiple RL under the RRC (Radio Resource Control ) control of the NG-RAN master anchor master base station. As shown in fig. 3, within a certain physical area, MN (Master Node, master base station) is typically used to provide wireless macro coverage. In areas of localized hot spots or weak coverage, a plurality of SNs (Secondary Node) are used to provide enhanced wireless micro coverage to improve the overall wireless capacity and performance of the cellular heterogeneous network.

Taking an MR-DC (Multi-Radio Dual Connectivity, multi-radio dual connection) operation mode supported by a 5G related protocol as an example, when a UE is in an overlapping coverage area of a MN primary service cell and an SN secondary service cell at the same time, NG-C and NG-U interface connection exists between the MN and the 5GC under the master control of the primary base station MN, xn-C and Xn-U interface connection exists between the MN and the SN, but only NG-U connection exists between the SN and the 5 GC. The entry, exit and all basic operations of the UE within the dual connectivity mode of operation are thus completed by the master base station MN. The master base station MN is based on RRM measurement reporting of UE aiming at the air interface continuously changing wireless conditions, RRM algorithm conditions of the master base station itself and the like, and the master control and decision of dual connection configuration, working state, wireless transmission and other resource coordination and the like between the MN and 5GC, SN and the UE are carried out. Most control plane operations between SN and 5GC, UE are accomplished by MN node forwarding through Xn-C interface connections. In fig. 4a and 4b, control plane connections between network element nodes are indicated by dashed lines and user plane connections between network element nodes are indicated by dash-dot lines. Fig. 4a is a diagram of an SN Terminated (Terminated) bearer type, focused between a network element node MN/SN and a UPF node (may be abbreviated as UPF), with two NG-U interface data transmission channels. The first channel is a data transmission channel between the UPF provided by NG-U (MN) and the MN, and is used to transmit uplink and downlink data packets carried on MN-side PDU (Protocol Data Unit ) Session/QoS (Quality of Service, quality of service) Flows. The establishment of this channel requires the UPF to provide the "MN side upstream data transfer channel address" and the MN to provide the "MN side downstream data transfer channel address". Similarly, the second channel is a data transmission channel between the UPF and the SN provided by the NG-U (SN) for transmitting uplink and downlink data packets carried on the SN side PDU Session/QoS flow. The establishment of this channel requires that the UPF provide the "SN side upstream data transfer channel address" and the SN provide the "SN side downstream data transfer channel address". For the SN Terminated bearer type, no Xn-U interface bearer needs to be established and maintained between MN and SN, since all user traffic data flows occur independently between UPF and the respective primary and secondary base stations. Fig. 4b is a diagram of a MN Terminated bearer type, focused between MN and UPF, with one of the following NG-U interface data transfer channels: NG-U (MN) provides a data transfer path between the UPF and the MN. But there is no NG-U interface data transfer channel between SN and UPF. In contrast to fig. 4a, fig. 4b does not have any NG-U (SN) channels. For the MN Terminated bearer type, in order to enable SN-side radio resource assisted transmission, an Xn-U bearer needs to be established and maintained between MN and SN, since all user traffic data flows need to occur between MN and SN. In summary, the supported dual/multi-connectivity operation must rely on the Xn-C interface between MN and SN, which is relied upon by multiple master and slave base stations participating in the dual/multi-connectivity operation to coordinate and update each other's resource allocation and operating state.

With the advent of various types of mobile base stations or network element nodes, for example: ground-based mobile base stations, aerial drone base stations, satellite base stations, etc., that provide a supply of wireless coverage/capacity for aerial vehicle cells that generally constantly changes as the physical location of the mobile base stations moves. These variations or periods are regular or irregular. The bearer transmission of interfaces NG, xn, etc. connecting these mobile base stations can no longer be the traditional fixed network transmission mode. Therefore, the carrier transmission cannot be carried out by a fixed network manner such as broadband optical fiber, and generally depends on a radio carrier manner, for example: relay technology means such as microwaves and lasers. Such cellular mobile networks, which are built up of numerous mobile base stations, although more flexible in terms of deployment (without fixed site resources), can only be planned and managed updated in a relatively dynamic manner for bearer transport between network resources and network element nodes. Otherwise, as each base station or network element node moves, the network topology or environmental conditions may change continuously, the old network element interface connection and configuration may fail, and the new network element interface connection and configuration is to be established and maintained. As shown in fig. 5a and 5 b: there are several antenna based satellite base stations Moving node1/2/3/4 … …, each providing a satellite service Beam from the air to a ground specific coverage area, forming a "small elliptical" coverage of ground service cell 1/2/3/4, respectively. But as the satellite base stations collectively move to the left along the orbit, the coverage of their respective provided terrestrial serving cells 1/2/3/4 … … also moves to the left with the satellite base stations, either continuously or hopped. Assuming that the ground also has a master base station MN providing "macro elliptical" radio coverage, the main difference with fig. 3 is that: the relative positional relationship between the "small ellipse" coverage provided by the satellite base station and the "large ellipse" coverage provided by the terrestrial MN base station may dynamically change. In addition, a relatively stable Xn interface connection may not be established between the satellite base station and the ground base station, otherwise, the establishment, deletion, establishment, and deletion … … of the Xn interface connection need to be continuously performed, and thus, continuous updating and maintenance are required.

The radio link of the terminal UE and the satellite base station is commonly called Service link, which is directed to the served UE and directly carries the user Service data and RRC signaling on the 5G NR Uu air interface. From the perspective of a single user terminal UE, even if the UE is stationary in place, the Service link of the UE changes accordingly as the satellite base station moves continuously. As shown in fig. 6, the radio links of the satellite base station and the serving ground station are commonly called Feeder links, which are used to further connect E2E (End to End) connections between the Service link and the ground core network, so as to implement control signaling and user data transmission between the UE and the ground network. The service ground station may include a central control network element node such as a satellite ground gateway NTN-GW (Non-Terrestrial Networks Gateway, non-ground network gateway), a core network, and the like. The Feeder link needs to provide at least the transmission function between the satellite base station and the ground core network 5 GC. If the satellite base station is a complete gNB, the Feeder link needs to provide stable transmission service for the NG interface, i.e. NGAP control signaling flow message and NG-U user service data can be transmitted. Although satellite base stations are moving at high speed all the time, it is usually defaulting that the Feeder link between them and the terrestrial gateway NTN-GW is sufficiently robust. Therefore, a relatively stable NG interface connection instance can be established, and the mode of multi-hop and relay routing through a plurality of NTN-GW transmission layers on the ground is adopted, so that frequent updating and maintenance of the NG interface instance are not required. As shown in fig. 6, when the satellite base station Moving Node1 gradually moves leftwards from the jurisdiction of the ground station 2 to the jurisdiction of the ground station 3, the NG interface instance between the default satellite base station and the ground core network anchor network element can be maintained unchanged through the ground transmission relay between the ground station 2 and the ground station 3. Therefore, the old NG interface connection is not deleted and the new NG interface connection is rebuilt, so that the process is repeated.

The characteristics of the double/multiple connection operation of the terminal UE comprise fixed physical positions of the main base station and the auxiliary base station, fixed and relatively robust Xn interface connection, MN master control and the like. The characteristics of the deployment work of the mobile base station represented by the satellite base station include that the satellite base station regularly and periodically moves along the orbit, the Xn interface connection is not fixed, the robustness is relatively low, and the like. If the UE needs to do double/multiple connection operation between the ground fixed base station and the mobile satellite base station (ground-air double/multiple connection for short), the UE can rely on a relatively more steady NG interface because the UE cannot rely on an Xn interface between the main base station and the auxiliary base station.

The application provides a method for controlling a terminal UE to perform double/multiple connection data transmission operation through a core network 5GC, which does not need to establish and maintain Xn interface connection (without Xn-C or Xn-U interface connection) between a main base station and an auxiliary base station. The 5GC and the main and auxiliary base stations are connected through NG interfaces respectively and simultaneously through NG-C and NG-U interfaces. The user plane bearer related to the present application is different from the SN Terminated bearer type of fig. 4a in that: the auxiliary base station SN and the AMF/SMF are also connected through independent NG-C interfaces, so that direct resource configuration management, working coordination and the like of the 5GC to the SN are realized.

Fig. 7 is a flowchart of a connection method according to an embodiment of the application. The method can be applied to the core network side. As shown in fig. 7, the method may include:

step S11, a first indication message is sent to a target auxiliary base station, wherein the first indication message comprises first indication information for executing appointed operation on auxiliary connection between the target auxiliary base station and a target terminal. The specifying operation includes setting up, adding, modifying, deleting or releasing for the secondary connection.

Step S12, a first response message from the target auxiliary base station is received, wherein the first response message comprises first result information corresponding to the first indication information.

In one embodiment, the operation of the assignment of the secondary connection may be initiated by the core network element. The core network element, for example, the 5GC, can sense whether the wireless connection states of the target terminal and the plurality of access network elements, for example, the base station, change. Examples of the change in wireless connection of the target terminal with the plurality of base stations may include: the target terminal changes from a single connection to a plurality of base stations, or the target terminal changes from a plurality of base stations to a single connection, or the number of base stations to which the target terminal is connected changes, or the base stations to which the target terminal is connected change, for example, from a connection to the base station A, B to a connection to the base station A, C.

If the 5GC senses that the wireless connection states of the target terminal and the plurality of base stations change, a first indication message can be sent to the target auxiliary base station, so that operations such as establishment, addition, modification, deletion or release and the like are performed on auxiliary connection between the target auxiliary base station and the target terminal.

After receiving the first indication message, the target auxiliary base station executes the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal. After the target secondary base station performs the designating operation, a first response message may be sent to the core network element to notify the core network element whether the performing of the designating operation is successful.

The following describes the types and contents of the first indication message and the first indication information corresponding to different operation scenes respectively.

Scene one: a scene is created or added.

In this scenario, the first indication message may be a secondary base station establishment request message or a secondary base station addition request message, where the first indication message includes available secondary connection capability and resource information in the target terminal, and user service feature information that needs to be shunted to the target secondary base station.

Scene II: the scene is modified.

In this scenario, the first indication message may be a secondary base station modification request message, where the first indication message includes user traffic characteristic information that needs to be streamed back from the target secondary base station to the primary base station, or user traffic characteristic information that is re-streamed to the target secondary base station.

Scene III: releasing or deleting the scene.

In this scenario, the first indication message may be a secondary base station release (release) command message or a secondary base station delete (delete) command message, where the first indication message includes user traffic feature information remaining on the target secondary base station that needs to be deleted.

In the embodiment of the application, the whole wireless link capability of the UE can be divided into a plurality of parts which are relatively independent. The first part is a primary connection capability and the second part is one or more secondary connection capabilities. For example, the primary connection capability of the UE is identified by the P-UE and the secondary connection capability is identified by the S-UE. In particular, the capability objects of various sharable attributes in the UE may be partitioned in a particular proportion. For example: and dividing sharable RF (Radio Frequency) and antenna module groups, power amplifiers, buffer resources, baseband processors and other hardware resources in the UE. For another example, the software resources such as Band Combination (Band Combination) information, bearer identification (RB id) and the like supported by the UE are divided. For another example, the protocol class resources, the code resource space, and the like are partitioned.

In the embodiment of the present application, the resource information of the target terminal may include resources that need to be used for establishing the auxiliary connection with the target terminal. For example, the user service that needs to be forked, reflowed or deleted is PDU session 1, the resource information of the target terminal may include radio resources related to the PDU session 1, and may further include a control plane, a user plane, a transmission resource, and the like connected to an S-NG interface related to the secondary base station.

In the embodiment of the application, the user service characteristic information in the indication information can comprise identification information (such as PDU Session id), bearing configuration information (such as QoS Flow Level QoS Parameters), a transmission channel address (such as UP Data Forwarding TNL Info) of data forwarding and the like of the user service. For example, if the user service to be forked, reflowed or deleted is PDU Session1, the identification information of the user service may be PDU Session1, the bearer configuration information of the user service may include QoS configuration parameters related to QoS Flows in PDU Session1, and the transmission channel address of the data forwarding may be PDU SessionTunnel tunnel address information of the data forwarding of PDU Session 1.

In one embodiment, after step S12, the method may further include:

and if the first result information indicates that the designated operation is successful, sending a second instruction message to the main base station, wherein the second instruction message comprises the first result information and main connection command information corresponding to the first result information.

Corresponding to the above scenario, the types and contents of the second indication message and the second indication message are respectively exemplified as follows:

Scene one: a scene is created or added.

In this scenario, the second indication message may be a secondary base station setup command message or a secondary base station addition command message, and the second indication message may include available primary connection capability and resource information in the target terminal, and user traffic characteristic information that has been shunted to the target secondary base station.

For example, in an establishment or addition scenario, the first result information in the second indication message may include feature information of user traffic, such as PDU sessions, etc., that the target secondary base station has established a secondary connection with the UE using the S-UE capability of the UE, has been offloaded to the target secondary base station, etc. The primary connection command information corresponding to the first result information may include current available primary connection capability and resource information of the UE. The second indication message may instruct the primary base station to delete the feature information of the user service such as the PDU session which is distributed to the target secondary base station from the primary base station, and may instruct the primary base station to establish primary connection with the UE by using the complete UE capability and resource, and update to establish primary connection with the UE by using the P-UE capability and resource of the UE.

Scene II: the scene is modified.

In this scenario, the second indication message may be a secondary base station modification command message, where the second indication message may include available primary connection capability and resource information in the target terminal, user service feature information that needs to be streamed to the primary base station, or user service feature information that has been streamed to the target secondary base station.

For example, in a modification scenario, the first result information in the second indication message may include feature information of user traffic such as a PDU session that needs to be streamed back to the primary base station or has been streamed to the target secondary base station. The primary connection command information corresponding to the first result information may include current available primary connection capability and resource information of the UE. The second indication message may indicate that the main base station deletes feature information of user services such as PDU session which is distributed to the target auxiliary base station from the main base station, adds feature information of user services which need to be reflowed to the main base station, and may also indicate that the main base station updates main connection with the UE by using currently available P-UE capability and resources of the UE.

Scene III: releasing or deleting the scene.

In this scenario, the second indication message may be a secondary base station release command message or a secondary base station delete command message, and the second indication message may include available primary connection capability and resource information in the target terminal, and remaining user service feature information on the target secondary base station that needs to be reflowed to the primary base station.

For example, in the release or deletion scenario, the first result information in the second indication message may include feature information of user traffic such as PDU sessions remaining on the target secondary base station that needs to be refluxed to the primary base station. The primary connection command information corresponding to the first result information may include current available primary connection capability and resource information of the UE. The second indication message may indicate that the characteristic information of the user traffic such as the PDU session deleted from the target secondary base station is reflowed to the primary base station. If all secondary base stations are released, from the case of multiple connections to a single connection, the second indication message may instruct the primary base station to re-use the full UE capabilities and resources to establish a primary connection with the UE.

In the embodiment of the application, the user service characteristic information can comprise identification information, bearing configuration information, a transmission channel address of data forwarding and the like of the user service. For example, the user service characteristic information in the first requirement information includes identification information of the user service. The user service characteristic information in the first indication information and the second indication information comprises bearing configuration information of user service, a transmission channel address of data forwarding and the like.

According to the method and the device, the core network element can directly instruct the target auxiliary base station to execute the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal, interaction between base stations is not needed, and the main auxiliary base station is instructed to update the main connection with the target terminal, so that the flexibility of multi-connection operation is improved.

Fig. 8 is a flowchart of a connection method according to another embodiment of the present application. The method can be applied to the core network side. As shown in fig. 8, the method may include:

step S21, receiving a first requirement message from a primary base station, where the first requirement message is sent by the primary base station when detecting that the wireless connection states of the target terminal and the plurality of base stations change, and the first requirement message includes first requirement information for executing the specified operation on the secondary connection. Wherein the first requirement information comprises requirement information for establishment, addition, modification, deletion or release of the secondary connection.

Step S22, a first indication message is sent to a target auxiliary base station, wherein the first indication message comprises first indication information for executing appointed operation on auxiliary connection between the target auxiliary base station and a target terminal. The specifying operation includes setting up, adding, modifying, deleting or releasing for the secondary connection.

Step S23, a first response message from the target auxiliary base station is received, wherein the first response message comprises first result information corresponding to the first indication information.

In one embodiment, the designated operation for the secondary connection may be initiated by the primary base station. The master base station may be aware of whether the radio connection state of the target terminal with multiple access network elements, e.g. base stations, has changed. Examples of the change in wireless connection of the target terminal with the plurality of base stations can be found in the description of the above embodiments. If the master base station senses that the wireless connection states of the target terminal and the plurality of base stations are changed, a first demand message can be sent to a core network element. And the core network element sends a first indication message to the target auxiliary base station. After receiving the first indication message, the target auxiliary base station executes specified operations such as establishment, addition, modification, deletion or release and the like on auxiliary connection between the target auxiliary base station and the target terminal. After the target secondary base station executes the designating operation, a first response message may be returned to the core network element to notify the core network element whether the execution of the designating operation is successful.

The types and contents of the first demand messages corresponding to different operation scenarios are respectively described below.

Scene one: a scene is created or added.

In this scenario, the first demand message establishes a demand message for the secondary base station or adds a demand message to the secondary base station, where the first demand message includes user service feature information that needs to be shunted to the target secondary base station.

Scene II: the scene is modified.

In this scenario, the first demand message is a secondary base station modification demand message, where the first demand message includes user service feature information that needs to be reflowed to the primary base station, or user service feature information that is re-streamed to the target secondary base station.

Scene III: releasing or deleting the scene.

In this scenario, the first demand message is a secondary base station release demand message or a secondary base station delete demand message, where the first demand message includes user service feature information remaining on the target secondary base station that needs to be deleted.

Accordingly, the types and contents of the first indication message and the first response message in the above scenario may be referred to the related description of the above embodiment, which is not repeated herein.

In one embodiment, after step S23, the method may further include:

And if the first result information indicates that the designated operation is successful, sending a second instruction message to the main base station, wherein the second instruction message comprises the first result information and main connection command information corresponding to the first result information. For example, in case that the operations of establishing, adding, modifying, deleting, releasing, etc. performed on the secondary connection are successful, the 5GC may transmit the second indication information to the primary base station. The type and content of the second indication message may be referred to the related description of the above embodiments, which is not repeated here.

In the embodiment of the application, the user service characteristic information can comprise identification information, bearing configuration information, a transmission channel address of data forwarding and the like of the user service. For example, the user service characteristic information in the second requirement information includes identification information of the user service. The user service characteristic information in the first indication information and the second indication information comprises bearing configuration information of user service, a transmission channel address of data forwarding and the like.

After receiving the demand information of the main base station, the embodiment can directly instruct the target auxiliary base station to execute the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal through the core network element, instruct the main auxiliary base station to update the main connection with the target terminal, does not need to rely on interaction between base stations, and is beneficial to improving the flexibility of multi-connection operation.

Fig. 9 is a flowchart of a connection method according to another embodiment of the present application. The method can be applied to the core network side. As shown in fig. 9, the method may include:

step S31, receiving a second requirement message from a target auxiliary base station, where the second requirement message is sent by the target auxiliary base station when detecting that the wireless connection states of the target terminal and the plurality of base stations change, the second requirement message includes second requirement information for executing the specified operation on the auxiliary connection, and the second requirement information includes requirement information for modifying, deleting or releasing the auxiliary connection.

Step S32, a third indication message is sent to the main base station, wherein the third indication message comprises main connection command information corresponding to the second requirement information.

Step S33, receiving a second response message from the master base station, where the second response message includes second result information corresponding to the master connection command information.

Step S34, a first indication message is sent to a target auxiliary base station, wherein the first indication message comprises first indication information for executing appointed operation on auxiliary connection between the target auxiliary base station and a target terminal. The specifying operation includes modification, deletion, or release for the secondary connection.

Step S35, receiving a first response message from the target secondary base station, where the first response message includes first result information corresponding to the first indication information.

In this embodiment, the secondary base station may initiate a specific operation for the secondary connection. The secondary base station may perceive whether the radio connection state of the target terminal with a plurality of access network elements, such as base stations, has changed. Examples of the change in wireless connection of the target terminal with the plurality of base stations can be found in the description of the above embodiments. If the target auxiliary base station senses that the wireless connection states of the target terminal and the plurality of base stations are changed, the second requirement information can be sent to the core network element. After receiving the second requirement information, the core network element may send a third indication message to the primary base station. And the main base station updates own user service and main connection according to the third indication message and returns a second response message to the core network element. After receiving the second response message, the core network element may send a first indication message to the target secondary base station. After receiving the first indication message, the target auxiliary base station can execute specified operations such as modification, deletion or release on auxiliary connection between the target auxiliary base station and the target terminal. After the target secondary base station executes the designating operation, a first response message may be returned to the core network element to notify the core network element whether the execution of the designating operation is successful.

The types and contents of the second demand messages corresponding to different operation scenarios are described below.

Scene one: the scene is modified.

In this scenario, the second requirement message may be a secondary base station modification requirement message, and the second requirement information includes user service feature information that needs to be reflowed to the primary base station.

The third indication message is a secondary base station modification request message, and the third indication message includes available main connection capability and resource information in the target terminal, and user service characteristic information which needs to be refluxed to the main base station.

The first indication information is an auxiliary base station modification command message, and the first indication information comprises available auxiliary connection capability and resource information in the target terminal and user service characteristic information which is reflowed to the main base station.

In this scenario, if the target secondary base station sends a secondary base station modification requirement message to the core network element. After receiving the modification requirement information of the auxiliary base station, the core network element can send the modification request information of the auxiliary base station to the main base station. And the main base station updates own user service and main connection according to the auxiliary base station modification request message and returns a second response message to the core network element. After receiving the second response message, the core network element may send an auxiliary base station modification command message to the target auxiliary base station. The target auxiliary base station receives the auxiliary base station modification command message, modifies the auxiliary connection with the target terminal, and can return a first response message to the core network element.

Scene II: releasing or deleting the scene.

In this scenario, the second requirement message is a secondary base station release requirement message or a secondary base station delete requirement message, where the second requirement message includes user service feature information remaining on the target secondary base station that needs to be deleted. The third indication message is a secondary base station release command message or a secondary base station deletion command message, and the third indication message includes available main connection capability and resource information in the target terminal, and user service characteristic information remaining on the target secondary base station which needs to be refluxed to the main base station. The first indication information is a secondary base station release command message or a secondary base station deletion command message, and the first indication information includes user service characteristic information remained on a target secondary base station to be deleted.

In this scenario, if the target secondary base station sends a secondary base station release requirement message or a secondary base station delete requirement message to the core network element. After receiving the secondary base station release requirement message or the secondary base station deletion requirement message, the core network element may send a secondary base station release command message or a secondary base station deletion command message to the primary base station. And the main base station updates own user service and main connection according to the auxiliary base station release command message or the auxiliary base station deletion command message, and returns a second response message to the core network element. After receiving the second response message, the core network element may send an auxiliary base station release command message or an auxiliary base station deletion command message to the target auxiliary base station. After receiving the auxiliary base station release command message or the auxiliary base station deletion command message, the target auxiliary base station deletes the auxiliary connection between the target auxiliary base station and the target terminal, returns a first response message to the core network element, and can release or delete the target auxiliary base station.

After receiving the demand information of the target auxiliary base station, the embodiment can directly instruct the target auxiliary base station to execute the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal through the core network element, instruct the main auxiliary base station to update the main connection with the target terminal, does not need to rely on interaction between base stations, and is beneficial to improving the flexibility of multi-connection operation.

Fig. 10 is a flowchart of a connection method according to another embodiment of the present application. The method can be applied to the access network side. As shown in fig. 10, the method may include:

step S41, a first indication message from a core network element is received, wherein the first indication message comprises first indication information for executing appointed operation on auxiliary connection between a target auxiliary base station and a target terminal. The specifying operation includes setting up, adding, modifying, deleting or releasing for the secondary connection.

And step S42, executing the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal.

Step S43, a first response message is sent to the core network element, wherein the first response message comprises first result information corresponding to the first indication message.

In one embodiment, the operation of the assignment of the secondary connection may be initiated by the core network element. The core network element, for example, the 5GC, can sense whether the wireless connection states of the target terminal and the plurality of access network elements, for example, the base station, change. Examples of the change in wireless connection of the target terminal with the plurality of base stations can be found in the description of the above embodiments. If the 5GC senses that the wireless connection states of the target terminal and the plurality of base stations are changed, a first indication message can be sent to the target auxiliary base station. After receiving the first indication message, the target auxiliary base station executes specified operations such as establishment, addition, modification, deletion or release on auxiliary connection between the target auxiliary base station and the target terminal. After the target secondary base station performs the designating operation, a first response message may be sent to the core network element to notify the core network element whether the performing of the designating operation is successful.

Scene one: a scene is created or added.

In this scenario, the first indication message may be a secondary base station establishment request message or a secondary base station addition request message, and the first indication message may include available secondary connection capability and resource information in the target terminal, and user service feature information that needs to be shunted to the target secondary base station.

Scene II: the scene is modified.

In this scenario, the first indication message may be a secondary base station modification request message, and the first indication message may include user traffic characteristic information that needs to be streamed back from the target secondary base station to the primary base station, or user traffic characteristic information that is re-streamed back to the target secondary base station.

Scene III: releasing or deleting the scene.

In this scenario, the first indication message may be a secondary base station release command message or a secondary base station deletion command message, and the first indication message may include user service feature information remaining on the target secondary base station that needs to be deleted.

Scene one: a scene is created or added.

Scene II: the scene is modified.

Scene III: releasing or deleting the scene.

In one embodiment, after step S43, the method may further include: receiving a second indication message from the core network element, wherein the second indication message is sent when the core network element indicates that the specified operation is successful in the first result information, and the second indication message comprises the first result information and main connection command information corresponding to the first result information.

In particular, if the first result information indicates that the designation operation is successful, the core network element may send a second indication message to the master base station. After receiving the second indication message, the main base station can update the main connection between the main base station and the target terminal.

The type and content of the first indication message, the first indication information, the first response message, the second indication message, etc. in the embodiment of fig. 7 are the same, and the related description of this embodiment may be referred to, and will not be repeated here.

Fig. 11 is a flowchart of a connection method according to another embodiment of the present application. The method can be applied to the access network side. As shown in fig. 11, the method may include:

step S51, when detecting that the wireless connection states of the target terminal and the plurality of base stations change, a first requirement message is sent to the core network element, where the first requirement message includes first requirement information for executing the specified operation on the auxiliary connection, and the first requirement message includes requirements for establishing, adding, modifying, deleting or releasing the auxiliary connection.

Step S52, receiving a first indication message from a core network element, where the first indication message includes first indication information for performing a specified operation on an auxiliary connection between a target auxiliary base station and a target terminal, and the specified operation includes establishment, addition, modification, deletion or release of the auxiliary connection.

And step S53, executing the appointed operation on the auxiliary connection between the target auxiliary base station and the target terminal.

Step S54, a first response message is sent to the core network element, where the first response message includes first result information corresponding to the first indication message.

Scene one: a scene is created or added.

Scene II: the scene is modified.

Scene III: releasing or deleting the scene.

In one embodiment, after step S54, the method may further include: receiving a second indication message from the core network element, wherein the second indication message is sent when the core network element indicates that the specified operation is successful in the first result information, and the second indication message comprises the first result information and main connection command information corresponding to the first result information.

The type and content of the first demand message, the first demand information, the first indication message, the first indication information, the first response message, the second indication message, etc. in the embodiment of fig. 8 are the same, and the related description of the embodiment may be referred to, and will not be repeated herein.

Fig. 12 is a flowchart of a connection method according to another embodiment of the present application. The method can be applied to the access network side. As shown in fig. 12, the method may include:

step S61, under the condition that the wireless connection state of the target terminal and the plurality of base stations is detected to be changed, a second demand message is sent to the core network element, wherein the second demand message comprises second demand information for executing the appointed operation on the auxiliary connection. The second requirement information includes a requirement for modification, deletion or release of the secondary connection.

Step S62, a third indication message from the core network element is received, wherein the third indication message comprises main connection command information corresponding to the second requirement information.

Step S63, a second response message is sent to the core network element, wherein the second response message comprises second result information corresponding to the main connection command information.

Step S64, a first indication message from a core network element is received, wherein the first indication message comprises first indication information for executing appointed operation on auxiliary connection between a target auxiliary base station and a target terminal. The specifying operation includes modification, deletion, or release for the secondary connection.

Step S65, executing the designating operation on the secondary connection between the target secondary base station and the target terminal.

Step S66, a first response message is sent to the core network element, wherein the first response message comprises first result information corresponding to the first indication message.

In this embodiment, the secondary base station may initiate a specific operation for the secondary connection. The secondary base station may perceive whether the radio connection state of the target terminal with a plurality of access network elements, such as base stations, has changed. Examples of the change in wireless connection of the target terminal with the plurality of base stations can be found in the description of the above embodiments. If the target auxiliary base station senses that the wireless connection states of the target terminal and the plurality of base stations are changed, the second requirement information can be sent to the core network element. After receiving the second requirement information, the core network element may send a third indication message to the primary base station. After receiving the third indication message, the main base station may update its own user service and main connection according to the third indication message, and then return a second response message to the core network element. After receiving the second response message, the core network element may send a first indication message to the target secondary base station. After receiving the first indication message, the target auxiliary base station can execute specified operations such as modification, deletion or release on auxiliary connection between the target auxiliary base station and the target terminal. After the target secondary base station executes the designating operation, a first response message may be returned to the core network element to notify the core network element whether the execution of the designating operation is successful.

Scene one: the scene is modified.

In this scenario, the second requirement message is a secondary base station modification requirement message, and the second requirement information includes user service feature information that needs to be reflowed to the primary base station. The third indication message is a secondary base station modification request message, and the third indication message includes available main connection capability and resource information in the target terminal, and user service characteristic information which needs to be refluxed to the main base station. The first indication information is an auxiliary base station modification command message, and the first indication information comprises available auxiliary connection capability and resource information in the target terminal and user service characteristic information which is reflowed to the main base station.

Scene II: releasing or deleting the scene.

The type and content of the second demand message, the second demand information, the third indication message, the second response information, the first indication message, the first indication information, the first response message, the second indication message, etc. in the embodiment of fig. 9 are the same, and reference may be made to the related description of the embodiment, which is not repeated herein.

In the embodiments corresponding to fig. 10, 11 and 12, in the new or added scenario, the designating operation is performed on the secondary connection between the target secondary base station and the target terminal, including: and establishing auxiliary connection with the target terminal according to the available auxiliary connection capability and resource information in the target terminal and user service characteristic information needing to be distributed to the target auxiliary base station so as to distribute the user service to the target auxiliary base station, so that the target auxiliary base station continues to bear transmission.

In a modification scenario, performing the specifying operation on the secondary connection between the target secondary base station and the target terminal includes: deleting the user service bearing transmission resources needing to reflow from the target auxiliary base station or distributing new bearing transmission resources for the re-distributed user service.

In the deletion scenario, executing the specified operation on the secondary connection between the target secondary base station and the target terminal, including: and deleting the residual user service bearer transmission resources from the target auxiliary base station, and releasing or deleting the target auxiliary base station.

The following is an example of the application of the present application in the dual connectivity mode, the principle of which is similar to that of the dual connectivity mode, and reference may be made to the related description of the dual connectivity mode.

As shown in fig. 13, the movement of the target SN has predictable regularity. An Xn interface connection between the target SN and the MN is not required, but the target SN and the 5GC may establish an S-NG interface connection. The 5GC and MN can speculatively predict by location and time information: when which target SN can be added as a offloading secondary base station. The overall radio link capability (or radio access capability UE Radio Access Capability) of a terminal UE served by a 5GS network is divided into two relatively independent parts. For example, denoted or identified by P-UE and S-UE, respectively. Wherein the sum of the respective capabilities and resource attributes of both the P-UE and the S-UE is equal to the total capability and resource of the UE. If the UE is able to connect to the primary base station and the plurality of secondary base stations simultaneously, the radio link capability may be divided into P-UE and a plurality of S-UEs.

Further, UE capability segmentation may be performed in a predefined static manner (relatively fixed segmentation); semi-static segmentation can be performed according to a command mode of a network side, namely specific segmentation capacity content and primary-secondary side proportion can be changed as required. The P-UE and S-UE capabilities may include a split in a particular ratio for sharable generic capability objects. Such as: and the Radio Frequency (RF) and antenna module group, buffer resource, baseband processor and other hardware resources or supported Frequency Band Combination (Band Combination) information, and bearing identification (RB id) and other software resources can be shared in the UE. The capabilities of P-UE and S-UE segmentation may also include segmentation for non-shared generic capabilities. Such as: for the UE supporting the multimode capability, the resources corresponding to one RAT format are all distributed to the P-UE, the resources corresponding to other RAT formats are all distributed to the S-UE, and the resources are not in the proportional division relationship.

Further, the "capability-segmented" UE may exhibit two relatively independent "virtual sub-UEs" to the outside energy within a certain observation or operation time window. Their respective sets of radio capabilities can be perceived and utilized by the master and secondary base stations MN/SN and the core network 5GC. Wherein the state and mobility of the P-UE represent the RRC state and mobility of the UE as a whole; the S-UE mainly provides an auxiliary distribution function of user plane data transmission, and the overall control plane attribute and the RRC state of the UE are not affected.

Before the UE enters the dual connectivity mode of operation, the master base station (MN) may utilize the full radio link capability of the UE and may report to the 5GC in advance via an NGAP flow message. The information of the possible P-UE and S-UE capability splitting modes is as follows:

option 1: P-UE x+S-UE y;

option 2: P-UE m+S-UE n

……；

Option x: P-UE k+S-UE h

And 5GC receives and stores the information of the capacity division modes of the P-UE and the S-UE, and then performs double connection operation for standby.

Several secondary connection related operations are initiated separately as follows.

The first way is: the MN initiates.

The master base station MN can speculatively predict by positioning and time information: when which target SN can be added as the shunting assisting base station SN, i.e. the target SN has the condition of performing a dual connectivity operation with the MN. Therefore, the network side can perform operations such as establishment, addition, modification, deletion or release on the SN, the RRM measurement report of the UE is not needed, and the MN can trigger to the 5GC in real time as required.

Further, the master base station MN may request 5GC to perform the establishment or addition operation of the specific target SN through the NGAP flow message. Such as: the MN sends NGAP to the 5 GC: SN Addition Required message, comprising: target SN information, and current MN-side user traffic data information to be offloaded by SN bearers, such as PDU Session/QoS flow id (identity), etc.

If the 5GC agrees to enter the dual connectivity mode of operation, the 5GC may instruct the MN to enter the dual connectivity mode of operation based on the NGAP flow message. The MN only uses the wireless link capability of the P-UE side indicated by the 5GC, and does not use the wireless link capability of the S-UE side. Such as: the MN receives the NGAP flow message from the 5 GC: SN Addition Command message indicating a certain 5GC selected P-UE x+S-UE y capability segmentation combination or related index identity, and user traffic data information successfully shunted by target SN admission, such as PDU Session/QoS flow id identity, etc.

After entering the dual connectivity mode of operation, the primary base station MN and UE establish and maintain a P-RL (primary radio link) with a P-NG-C primary control plane connection and P-NG-U primary user plane connection instance with the 5GC, which are used to transmit control signaling and user traffic data on the MN side, in particular various operations similar to the UE single connectivity operation.

Further, the master base station MN may request, through the NGAP flow message, the 5GC to perform operations such as modification, deletion, or release for the current target SN. Such as: the MN sends NGAP to the 5 GC: SN Modification Required message or SN Release Required message, including the target SN to be modified or deleted and related user traffic data information. Similarly, if the 5GC agrees to modify or exit the dual connectivity mode of operation, the MN receives an NGAP flow message from the 5 GC: SN Modification Command or SN Release Command message including the modified or deleted target SN and related user traffic data information as confirmed by the 5 GC.

The second way is: 5GC initiation.

5GC can also speculatively predict by location and time information: when the managed target MN can add which target SN is used as the shunting auxiliary base station SN, namely the target MN and the SN have the condition of performing double connection operation in which time window. Therefore, the 5GC can actively trigger and decide the operations of setting up, adding, modifying, deleting or releasing the SN at the network side, and the NGAP uplink message request of the master base station MN is not required.

Further, if the 5GC receives a request from the base station MN for a target SN set up, add, modify, delete or release operation, it can be decided whether to enter, modify or exit the dual connectivity operation mode.

If the 5GC decides to enter the dual-connection working mode, an SN adding request operation is sent to the target SN through an NGAP flow message, and an S-NG-C auxiliary control surface connection, an S-NG-U auxiliary user surface connection instance and a wireless link resource related to an SN auxiliary base station side are attempted to be established. Depending on how much UE user traffic data needs to be offloaded to the SN side by the MN or 5 GC. Such as: the 5GC sends an NGAP flow message to the target SN: SN Addition Request, which includes user traffic data information originally belonging to the MN side to be established by the SN offload bearer, such as PDU Session/QoS flow id identification. Similarly, the 5GC may also send an NGAP flow message to the target SN: SN Modification Request or SN Release Command message, which includes user traffic data information of the current SN side to be SN modified or deleted, such as PDU Session/QoS flow id identification.

Third mode: SN initiation.

The target auxiliary base station SN tries to establish an S-NG-C auxiliary control surface connection, an S-NG-U auxiliary user surface connection instance and a wireless link resource related to the SN auxiliary base station side based on the NGAP flow message from the 5GC, and replies the SN establishment result to the 5GC through the NGAP flow message. Such as: the SN sends an NGAP flow message to the 5 GC: SN Addition Request Acknowledge, which includes user traffic Data information of successful and failed establishment, such as PDU Session/QoS flow id identification and Data Forwarding transmission channel address, etc. Similarly, the target secondary station SN attempts to perform SN modification or deletion related operations based on the NGAP flow message from the 5GC, and replies to the 5GC with the result of the modification or deletion. Such as: the SN sends an NGAP flow message to the 5 GC: SN Modification Request Acknowledge or SN Release Complete message.

After the UE enters the dual connectivity mode of operation, the secondary base station SN and the UE establish and maintain an S-RL secondary radio link, and there are S-NG-C secondary control plane connection and S-NG-U secondary user plane connection instances with the 5GC, which are used to transmit control signaling and user traffic data on the SN side, and specific operations are similar to the current UE single connectivity operation.

Further, the secondary base station SN may actively request the 5GC to perform modification and deletion operations of the current SN through the NGAP flow message, for example: the SN actively triggers and sends an NGAP flow message to the 5 GC: SN Modification Required message or SN Release Required message, which includes user traffic data information of the current SN side to be SN modified or deleted, such as PDU Session/QoS flow id identification.

The 5GC may decide whether to exit the current dual connectivity mode of operation by itself on an internal implementation without the SN Release Required message request of the MN or SN. If the 5GC decides to exit the dual connectivity mode of operation, then the single connectivity mode of operation is resumed by commanding the target MN and SN via the NGAP flow message. The MN may then resume utilizing the full radio link capabilities of the entire UE, such as: the 5GC sends NGAP flow messages to the target MN and the SN respectively: SN Release Command message.

After the UE exits the dual connectivity mode, the S-NG-C secondary control plane connection, the S-NG-U secondary user plane connection instance, and the radio link resources associated with the SN secondary base station side may be released or temporarily reserved by the SN secondary base station but deactivated for non-operation. The radio link resources associated with the primary base station side of the MN can be reconfigured and updated for all of the P-NG-C primary control plane connection, the P-NG-U primary user plane connection instance, and the MN primary base station side.

The application provides a method for performing double/multiple connection data transmission operation by a core network (5 GC) master control UE. The method does not need to establish or maintain Xn interface connection (for example, there may be no Xn-C or Xn-U interface connection) between the main and auxiliary base stations, and the 5GC and the main and auxiliary base stations need to establish and maintain independent NG interface connection (simultaneously establish NG-C and NG-U interface connection). The network side manages the dual/multi-connection working mode of the UE, does not need to rely on RRM measurement report of the UE for the target SN, and can predict and infer the condition relation of dual/multi-connection operation between the target MN and the SN by utilizing prior information such as self base station positioning and time (such as ephemeris information of a satellite base station), thereby more flexibly managing the dual/multi-connection working mode of the UE. The application can support the basic operation that MN and SN trigger some double/multiple connections respectively, and the 5GC makes the final decision and the management of the user service data shunt and reflux.

Application example 1: the MN initiates a procedure to establish or add the SN.

As shown in fig. 14 a: in some LEO low earth orbit satellite communication systems, a plurality of LEO low earth satellites are in a particular near earth orbit. The satellites may periodically orbit the earth in accordance with predetermined ephemeris information. They carry the complete gNB base station functionality (known as gNB type satellites) and provide satellite radio access services for terrestrial user UEs. A number of satellite ground station gateway (NTN-GW) entities are deployed on the ground, integrated within a 5GC core network entity. Each LEO satellite depends on the positioning capability of the LEO satellite, and can timely establish and maintain one or more Feeder link bearing transmission links respectively with one or more NTN-GW/5GC on the ground according to the physical longitude and latitude position of the current operation, so as to bear and transmit the NG interface connection instance. Each LEO satellite may project beam coverage (a large ellipse in fig. 14a, typically with a much larger coverage radius than the coverage of the serving cell of the ground base station) for a predetermined area of the ground. As LEO satellites move, these satellite beam coverage also slide across the ground, forming an inter-frequency overlapping coverage with ground-based ground cellular coverage (small ellipses in fig. 14 a).

As shown in fig. 14b, the MN initiated SN addition procedure may include the steps of:

S100: at time T1, satellite base station A-gNB1 is connected to NTN-GW/5GC1 by anchor point, and ground base station MN is also connected to same NTN-GW/5GC1 by anchor point. The MN and the 5GC1 possess ephemeris information of the LEO low-orbit satellite system according to the network management configuration information. For example, which LEO satellite will travel to which orbital position, which area the satellite's corresponding beam ground covers approximately, etc. Thus, MN and 5GC1 can be surmised to know: during a period of observation time before and after T1, the ground coverage of the satellite base station a-gNB1 beam and the radio coverage of the main base station MN overlap to some extent, so that the ground-air dual connectivity operation is possible. A UE in a connected state is being served by a cell (small oval in fig. 14 a) of a master base station MN, and radio resources and NG interface connection transmission channels related to PDU Session1 (PDU Session 1) and PDU Session2 (PDU Session 2) user traffic data are established. The UE supports the P-UE and S-UE capability segmentation of the present application and reports supportable capability segmentation information to MN and 5GC1. PDU Session1 user traffic data may be carried by the LEO satellite radio link according to a local policy (e.g., roaming security or billing factors) of the converged integrated cellular system. In step S100, the MN may report and cooperate with the information of the P-UE and S-UE capabilities and resource segmentation supported by the UE through a terminal radio capability report (UE RADIO CAPABILITY REPORT) message or a terminal capability information indication (UE CAPABILITY INFO INDICATION) message.

S101: the MN sends a secondary base station addition requirement (SN ADDITION REQUIRED) message to the 5GC1 at a proper moment according to the ephemeris information of the LEO low orbit satellite system without depending on RRM measurement report of the UE. The message includes a request to offload all QoS Flows in PDU Session1 currently being carried by the MN to the target secondary base station SN-gNB1. The MN may also propose a Data Forwarding (Data Forwarding) operation to reduce packet loss during the offloading operation. The data forwarding may include sending the remaining unsuccessfully sent data packets of the user service to be shunted to the source node side to the 5GC1.

S102: and 5GC1 receives the demand message of the MN, and determines that all QoS Flows in PDU Session1 can be shunted to the target SN-gNB1 according to the ephemeris information of the LEO low-orbit satellite system and the system local strategy. The 5GC1 sends a secondary base station addition request (SN ADDITION REQUEST) message to the SN-gNB1. The message includes the S-UE capability informing the target SN-gNB1, the request to establish PDU Session1 related wireless resource at the SN-gNB1 side, and the control plane, user plane and transmission resource of the S-NG interface connection.

S103: and the SN-gNB1 receives the request message of the 5GC1 and performs local resource admission control. If SN-gNB1 determines that all relevant resources can be successfully established for PDU Session1, a secondary base station addition response message, such as a secondary base station addition acknowledgement (SN ADDITION REQUEST ACKNOWLEDGE) message, can be sent to 5GC1. The message includes notification 5GC1 that PDU Session1 has been successfully established, related radio resources on the SN-gNB1 side, control plane, user plane, transmission resources connected with the S-NG interface, and the like. The SN-gNB1 may also provide transport address information for Data Forwarding (Data Forwarding) at the same time to implement Data Forwarding operation from the MN side.

S104: the 5GC1 receives the confirmation message of the SN-gNB1, knows that the SN-gNB1 side has successfully shunted and established PDU Session1, and can send an auxiliary base station adding command (SN ADDITION COMMAND) message to the MN. The message includes the P-UE capability and resources available after the MN enters dual connectivity operation, and the result of having successfully offloaded PDU Session1 to SN-gNB1 side. The MN may then delete the related radio resources of the original service PDU Session1, control plane, user plane, transport resources, etc. connected to the P-NG interface.

After S104: the P-RL wireless link is established and maintained between the MN and the P-UE through the RRC reconfiguration message, and only PDU Session2 user service data is transmitted thereafter. An S-RL wireless link is established and maintained between the SN-gNB1 and the S-UE through an RRC reconfiguration message, and only PDU Session1 user service data is transmitted thereafter.

The ADDITION (ADDITION) in this application example is sometimes also referred to as Creation (CREATE). Accordingly, messages related to the addition may also be modified to messages related to the establishment. For example, a secondary base station setup requirement (SN CREATE REQUIRED) message, a secondary base station setup request (SN CREATE REQUEST) message, a secondary base station setup confirm (SN CREATE REQUEST ACKNOWLEDGE) message, a secondary base station setup command (SN CREATE COMMAND) message, and the like. The following other application examples are similar, and will not be described in detail.

Application example 2: the MN initiates a procedure to modify the SN.

As shown in fig. 15 a: in some LEO low earth orbit satellite communication systems, a plurality of LEO low earth satellites are in a particular near earth orbit. The satellites may periodically orbit the earth in accordance with predetermined ephemeris information. They carry the complete gNB base station functionality (known as gNB type satellites) and provide satellite radio access services for terrestrial user UEs. A number of satellite ground station gateway NTN-GW entities are deployed on the ground, integrated within a 5GC core network entity. Each LEO satellite depends on the positioning capability of the LEO satellite, and can timely establish and maintain one or more Feeder link bearing transmission links respectively with one or more NTN-GW/5GC on the ground according to the physical longitude and latitude position of the current operation, so as to bear and transmit the NG interface connection instance. Each LEO satellite may project beam coverage (the large ellipse in fig. 15a, typically with a much larger coverage radius than the coverage of the serving cell of the ground base station) for a predetermined area of the ground. As LEO satellites move, these satellite beam coverage also slide across the ground, forming an inter-frequency overlapping coverage with ground-based ground cellular coverage (small ellipses in fig. 15 a).

As shown in fig. 15b, the MN initiated procedure to modify the SN may include the steps of:

S200: at time T2 after T1, the continuously moving satellite base station A-gNB1 is still connected to the NTN-GW/5GC1 in an anchor mode, and meanwhile, the ground base station MN is also connected to the same NTN-GW/5GC1 in an anchor mode. The MN and the 5GC1 possess ephemeris information of the LEO low-orbit satellite system according to the network management configuration information. For example, which LEO satellite will travel to which orbital position, and what area the satellite's corresponding beam ground covers is likely to be. Thus, both MN and 5GC1 can be surmised to know: during a period of observation time before and after T2, the ground coverage of the satellite base station a-gNB1 beam and the radio coverage of the main base station MN overlap to a certain extent, so that the ground-air dual connectivity operation can be continuously maintained. Some UE already in ground-air dual connectivity operation is being served by both the primary MN cell (small oval in fig. 15 a) and the secondary SN-gNB1 cell (large oval in fig. 15 a), and radio resources and NG interface connection transmission channels related to PDU Session2 and PDU Session1 user traffic data have been established, respectively. The UE supports the P-UE and S-UE capability segmentation of the application and reports updated capability segmentation information to MN and 5GC1. According to the system local policy (such as roaming security or charging factor), part of the QoS flow user service data in PDU Session1 needs to be streamed back to MN bearer transport. In step S200, the MN may report the updated information of the P-UE and S-UE capability segmentation supported by the UE through a terminal radio capability report (UE RADIO CAPABILITY REPORT) message or a terminal capability information indication (UE CAPABILITY INFO INDICATION) message.

S201: the MN sends a secondary base station modification requirement (SN MODIFICATION REQUIRED) message to the 5GC1 at a proper moment according to the ephemeris information of the LEO low orbit satellite system without depending on RRM measurement report of the UE. The message includes: the request is to reflux part of QoS Flows in PDU Session1 currently being carried by SN-gNB1 side to MN for carrying transmission. The MN may also propose a Data Forwarding (Data Forwarding) operation, and the message may provide corresponding Data Forwarding address information to reduce packet loss in the reflow operation.

S202: the 5GC1 receives the demand message of the MN, and determines that part of QoS Flows in the PDU Session1 can be returned to the MN according to the ephemeris information of the LEO low orbit satellite system and the system local strategy. The 5GC1 sends a secondary base station modification request (SN MODIFICATION REQUEST) message to the target SN-gNB 1. The message includes the S-UE capability available after the update of the notification target SN-gNB1, requests to reconfigure the related wireless resources of the rest PDU Session1, the control plane, the user plane, the transmission resources and the like of the S-NG interface connection at the side of the SN-gNB 1.

S203: and the SN-gNB1 receives the request message of 5GC1, removes part of QoS Flows and related resources in the PDU Session1 to be reflowed, and reconfigures the rest part of PDU Session1. The SN-gNB1 then sends a secondary base station modification response message, such as a secondary base station modification acknowledgement (SN MODIFICATION REQUEST ACKNOWLEDGE) message, to 5GC 1. The message includes notification 5GC1 that the partial QoS Flows and related resources in PDU Session1 have been successfully deleted, and related radio resources on SN-gNB1 side, control plane, user plane, and transmission resources of S-NG interface connection are successfully reconfigured. The SN-gNB1 may also perform Data Forwarding (Data Forwarding) operations for the reflowed partial QoS Flows.

S204: the 5GC1 receives the confirmation message of the SN-gNB1, knows that the SN-gNB1 side has successfully deleted part of QoS Flows and related resources in the PDU Session1, and can send SN MODIFICATION COMMAND message to the MN. The message includes information informing the MN of the P-UE capability and resources available after maintaining the dual connectivity operation update and the need to successfully reflow part of the QoS Flows in PDU Session1 to the MN side. The MN then re-establishes part of the QoS Flows and related radio resources in the returned PDU Session1, control plane, user plane and transport resources for the P-NG interface connection, etc.

After S204: and continuing to maintain the P-RL wireless link between the MN and the P-UE through the RRC reconfiguration message, and continuing to transmit PDU Session2 user service data and partially reflowed PDU Session1 user service data. And continuing to maintain the S-RL wireless link between the SN-gNB1 and the S-UE through an RRC reconfiguration message, and continuing to transmit part of the remained PDU Session1 user service data.

Application example 3: the MN initiates a procedure to release or delete the SN.

As shown in fig. 16 a: in some LEO low earth orbit satellite communication systems, a plurality of LEO low earth satellites are in a particular near earth orbit. The satellites may periodically orbit the earth in accordance with predetermined ephemeris information. They carry the complete gNB base station functionality (known as gNB type satellites) and provide satellite radio access services for terrestrial user UEs. A number of satellite ground station gateway (NTN-GW) entities are deployed on the ground, integrated within a 5GC core network entity. Each LEO satellite depends on the positioning capability of the LEO satellite, and can timely establish and maintain one or more Feeder link bearing transmission links respectively with one or more NTN-GW/5GC on the ground according to the physical longitude and latitude position of the current operation, so as to bear and transmit the NG interface connection instance. Each LEO satellite may project beam coverage (the large ellipse in fig. 16a, typically with a much larger coverage radius than the coverage of the serving cell of the ground base station) for a predetermined area of the ground. As LEO satellites move, these satellite beam coverage also slide across the ground, forming an inter-frequency overlapping coverage with ground-based ground cellular coverage (small ellipses in fig. 16 a).

As shown in fig. 16b, the MN initiated SN release procedure may include the steps of:

s300: at time T3 after T2, the continuously moving satellite base station A-gNB1 is still connected to the NTN-GW/5GC1 in an anchor mode, and meanwhile, the ground base station MN is also connected to the same NTN-GW/5GC1 in an anchor mode. Both the MN and the 5GC1 have ephemeris information of the LEO low-orbit satellite system according to the network management configuration information. For example, which LEO satellite will travel to which orbital position, which area the satellite's corresponding beam ground cover is likely to be in, etc. Thus, MN and 5GC1 can be surmised to know: the overlap of the ground coverage of the satellite base station a-gNB1 beam and the radio coverage of the master base station MN will gradually disappear during a period of observation time before and after T3, so that the UE needs to exit and the ground-air dual connectivity operation of the satellite base station a-gNB 1. The MN may continue to attempt to establish with the following satellite base station B-gNB2 to enter a new ground-air dual connectivity operation. Some UE already in ground-air dual connectivity operation is being served by both the primary MN cell (small oval in fig. 16 a) and the secondary SN-gNB1 cell (large oval in fig. 16 a), and radio resources and NG interface connection transmission channels related to PDU Session2 and PDU Session1 user traffic data have been established, respectively. The UE supports the P-UE and S-UE capability segmentation of the present application and has reported updated capability segmentation information to MN and 5GC1. Since the beam coverage of the satellite base station a-gNB1 will be lost, the remaining QoS flow user service data in the PDU Session1 needs to be all reflowed to the MN to continue the bearer transmission, and the satellite base station a-gNB1 will be deleted as the secondary base station. In step S300, the MN may report the updated information of the P-UE and S-UE capabilities and resource segmentation supported by the UE through a terminal radio capability report (UE RADIO CAPABILITY REPORT) message or a terminal capability information indication (UE CAPABILITY INFO INDICATION) message.

S301: the MN sends a secondary base station release request (SN RELEASE REQUIRED) message to the 5GC1 at the appropriate time according to the ephemeris information of the LEO low orbit satellite system, independent of the RRM measurement report of the UE. The message includes a request to completely reflux the rest QoS flow in the PDU Session1 currently being carried and served by the SN-gNB1 side to the MN for carrying and transmitting, thereby deleting the SN-gNB1 serving as the UE auxiliary base station and exiting the ground-air double connection operation. The MN can also propose a Data Forwarding operation, and provide corresponding Data Forwarding address information in the message so as to reduce Data packet loss in the reflow operation.

S302: the 5GC1 receives the demand message of the MN, and judges that the rest QoS Flows in the PDU Session1 can be completely reflowed to the MN according to the ephemeris information of the LEO low orbit satellite system and the system local strategy. The 5GC1 sends a secondary base station release COMMAND (SN RELEASE COMMAND) message to the target SN-gNB1. The message includes informing the target SN-gNB1 of releasing, requesting to delete the residual QoS flow related wireless resources in the service PDU Session1 of the SN-gNB1 side, and the control plane, the user plane, the transmission resources and the like of the S-NG interface connection.

S303: the SN-gNB1 receives the request message of 5GC1, and may delete the remaining QoS Flows and all relevant resources in the PDU Session1 to be reflowed, and send a secondary base station release response message to 5GC1 after completion, for example: the secondary base station releases a COMPLETE (SN RELEASE COMPLETE) message. The message includes notification that 5GC1 has successfully deleted the remaining QoS Flows and all relevant resources in PDU Session1 and has deleted SN-gNB1 as the UE secondary base station. SN-gNB1 may also perform Data Forwarding (Data Forwarding) operations for the remaining QoS Flows of the reflow.

S304: the 5GC1 receives the release completion message of the SN-gNB1, and knows that the SN-gNB1 has successfully deleted the remaining QoS Flows and all relevant resources in the PDU Session1, so as to send a secondary base station release order (SN RELEASE COMMAND) message to the MN. The message includes the entire UE capability available after the MN is informed to exit the dual connectivity operation, and the need to successfully reflow the remaining QoS Flows in PDU Session1 to the MN side. The MN then re-establishes the remaining QoS Flows and associated radio resources in the returned PDU Session1, control plane, user plane, transport resources, etc. for interfacing with the P-NG.

After S304: and continuing to maintain the P-RL wireless link through the RRC reconfiguration message between the MN and the UE, and continuing to transmit PDU Session2 user service data and PDU Session1 user service data which are completely reflowed. The original S-RL wireless link is deleted between the SN-gNB1 and the S-UE through the RRC release message, and the SN-gNB1 does not serve to transmit any PDU Session user service data.

Release (RELEASE) in this application example is sometimes also referred to as DELETE (DELETE). Accordingly, the release-related message may be modified to a delete-related message. For example, a secondary base station delete requirement (SN DELETE REQUIRED) message, a secondary base station delete command (SN DELETE COMMAND) message, a secondary base station delete success (SN DELETE COMPLETE) message, and the like. The following other application examples are similar, and will not be described in detail.

Application example 4: the 5GC initiates the flow of creating or adding the SN.

As shown in fig. 17 a: in some LEO low earth orbit satellite communication systems, a plurality of LEO low earth satellites are in a particular near earth orbit. The satellites may periodically orbit the earth in accordance with predetermined ephemeris information. They carry the complete gNB base station functionality (known as gNB type satellites) and provide satellite radio access services for terrestrial user UEs. A number of satellite ground station gateway (NTN-GW) entities are deployed on the ground, integrated within a 5GC core network entity. Each LEO satellite depends on the positioning capability of the LEO satellite, and can timely establish and maintain one or more Feeder link bearing transmission links respectively with one or more NTN-GW/5GC on the ground according to the physical longitude and latitude position of the current operation, so as to bear and transmit the NG interface connection instance. Each LEO satellite may project beam coverage (a large ellipse in fig. 17a, typically with a much larger coverage radius than the coverage of the serving cell of the ground base station) for a predetermined area of the ground. As LEO satellites move, these satellite beam coverage also slide across the ground, forming an inter-frequency overlapping coverage with ground-based ground cellular coverage (small ellipses in fig. 17 a). In step S400, the MN may report and cooperate with the information of the P-UE and S-UE capability segmentation supported by the UE through a terminal radio capability report (UE RADIO CAPABILITY REPORT) message or a terminal capability information indication (UE CAPABILITY INFO INDICATION) message.

As shown in fig. 17b, the flow of 5GC initiated SN addition may include the following steps:

s400: at time T1, satellite base station A-gNB1 is connected to NTN-GW/5GC1 by anchor point, and ground base station MN is also connected to same NTN-GW/5GC1 by anchor point. The MN and the 5GC1 possess ephemeris information of the LEO low-orbit satellite system according to the network management configuration information. For example, which LEO satellite will travel to which orbital position, and which area the satellite's corresponding beam ground covers approximately. Etc. Thus, both MN and 5GC1 can be surmised to know: during a period of observation time before and after T1, the ground coverage of the satellite base station a-gNB1 beam and the radio coverage of the main base station MN overlap to some extent, so that the ground-air dual connectivity operation is possible. A UE in a connected state is being served by a cell (small oval in fig. 17 a) of the master base station MN, and radio resources and NG interface connection transmission channels related to PDU Session1 and PDU Session2 user service data are already established. The UE supports the P-UE and S-UE capability segmentation of the present application and reports supportable capability segmentation information to MN and 5GC1. PDU Session2 user traffic data may be carried by the LEO satellite radio link according to system local policies (e.g., roaming Security or billing factors).

S401: the 5GC1 decides that all QoS Flows in the PDU Session2 can be shunted to the target SN-gNB1 according to the ephemeris information of the LEO low-orbit satellite system and the system local strategy, so that the 5GC1 directly sends a secondary base station adding request (SN ADDITION REQUEST) message to the target SN-gNB1 at the proper moment. The message includes the S-UE capability informing the target SN-gNB1, the request to establish PDU Session1 related wireless resource at the SN-gNB1 side, and the control plane, user plane and transmission resource of the S-NG interface connection.

S402: and the SN-gNB1 receives the request message of the 5GC1 and performs local resource admission control. If SN-gNB1 determines that all relevant resources can be successfully established for PDU Session2, a secondary base station addition response message, such as a secondary base station addition acknowledgement (SN ADDITION REQUEST ACKNOWLEDGE) message, can be sent to 5GC 1. The message includes notification 5GC1 that PDU Session2 has been successfully established, related radio resources on the SN-gNB1 side, control plane, user plane, transmission resources connected with the S-NG interface, and the like. The SN-gNB1 may also provide transport address information for Data Forwarding (Data Forwarding) at the same time to implement Data Forwarding operation from the MN side.

S403: the 5GC1 receives the confirmation message of the SN-gNB1, knows that the SN-gNB1 side has successfully shunted and established PDU Session2, and can send an auxiliary base station adding command (SN ADDITION COMMAND) message to the MN. The message includes the P-UE capability and resources available after the MN enters dual connectivity operation, and the result of having successfully offloaded PDU Session2 to SN-gNB1 side. The MN may then delete the related radio resources of the original service PDU Session2, control plane, user plane, transport resources, etc. connected to the P-NG interface.

After S403: the P-RL wireless link is established and maintained between the MN and the P-UE through the RRC reconfiguration message, and only PDU Session1 user service data is transmitted thereafter. An S-RL wireless link is established and maintained between the SN-gNB1 and the S-UE through an RRC reconfiguration message, and only PDU Session2 user service data is transmitted thereafter.

Application example 5: the SN initiates a flow to modify the SN.

As shown in fig. 18 a: in some LEO low earth orbit satellite communication systems, a plurality of LEO low earth satellites are in a particular near earth orbit. The satellites may periodically orbit the earth in accordance with predetermined ephemeris information. They carry the complete gNB base station functionality (known as gNB type satellites) and provide satellite radio access services for terrestrial user UEs. A number of satellite ground station gateway (NTN-GW) entities are deployed on the ground, integrated within a 5GC core network entity. Each LEO satellite depends on the positioning capability of the LEO satellite, and can timely establish and maintain one or more Feeder link bearing transmission links respectively with one or more NTN-GW/5GC on the ground according to the physical longitude and latitude position of the current operation, so as to bear and transmit the NG interface connection instance. Each LEO satellite may project beam coverage (a large ellipse in fig. 18a, typically with a much larger coverage radius than the coverage of the serving cell of the ground base station) for a predetermined area of the ground. As LEO satellites move, these satellite beam coverage also slide across the ground, forming an inter-frequency overlapping coverage with ground-based ground cellular coverage (small ellipses in fig. 18 a).

As shown in fig. 18b, the flow of SN initiated modification SN may include the steps of:

s500: at time T2 after T1, the continuously moving satellite base station A-gNB1 is still connected to the NTN-GW/5GC1 in an anchor mode, and meanwhile, the ground base station MN is also connected to the same NTN-GW/5GC1 in an anchor mode. The MN and the 5GC1 possess ephemeris information of the LEO low-orbit satellite system according to the network management configuration information. For example, which LEO satellite will travel to which orbital position, which area the corresponding beam ground cover is likely to be in, etc. Thus, MN and 5GC1 can be surmised to know: during a period of observation time before and after T2, the ground coverage of the satellite base station a-gNB1 beam and the radio coverage of the main base station MN still overlap to some extent, so that the ground-air dual connectivity operation can be continuously maintained. Some UE already in ground-air dual connectivity operation is being served by both the primary MN cell (small oval in fig. 18 a) and the secondary SN-gNB1 cell (large oval in fig. 18 a), and radio resources and NG interface connection transmission channels related to PDU Session1 and PDU Session2 user traffic data have been established, respectively. The UE supports the P-UE and S-UE capability segmentation of the application and reports updated capability segmentation information to MN and 5GC1. Due to the fact that the local load of the SN-gNB1 satellite is too heavy, the SN-gNB1 wants to reflow part of the QoS flow user service data in the PDU Session2 to the MN to continue the bearer transmission. In step S500, the MN may report the updated information of the P-UE and S-UE capability segmentation supported by the UE through a terminal radio capability report (UE RADIO CAPABILITY REPORT) message or a terminal capability information indication (UE CAPABILITY INFO INDICATION) message.

S501: the SN-gNB1 actively transmits a secondary base station modification requirement (SN MODIFICATION REQUIRED) message to the 5GC1 at a proper moment according to ephemeris information of the LEO low orbit satellite system without depending on RRM measurement report of the UE. The message includes a request to reflux part of QoS Flows in PDU Session2 currently being carried by SN-gNB1 side to MN for carrying transmission. The SN-gNB1 may also suggest a Data Forwarding (Data Forwarding) operation to reduce Data packet loss during the reflow operation.

S502: the 5GC1 receives the request message of the SN-gNB1, and judges that part of QoS Flows in the PDU Session2 can be reflowed to the MN according to the ephemeris information of the LEO low-orbit satellite system and the local strategy of the system. The 5GC1 sends a secondary base station modification request (SN MODIFICATION REQUEST) message to the MN. The message includes the P-UE capability and resource which can be used after the update of the MN, and the request to reconfigure the radio resource related to the returned partial PDU Session2, the control plane, the user plane and the transmission resource of the P-NG interface connection at the MN side.

S503: the MN receives the 5GC1 request message. If the partial QoS Flows and related resources in the returned PDU Session2 were successfully established, a secondary-base-station modification response message, such as a secondary-base-station modification acknowledgement (SN MODIFICATION REQUEST ACKNOWLEDGE) message, may be sent to 5GC 1. The message includes notification 5GC1 that a part of QoS Flows and related resources in PDU Session2 have been successfully established, and related radio resources on the MN side, control plane, user plane, and transmission resources of the P-NG interface connection, etc. are successfully reconfigured. The MN may also provide Data Forwarding (Data Forwarding) transport address information in the above message for the reflowed partial QoS Flows.

S504: the 5GC1 receives the acknowledgement message of the MN, knows that the MN side has successfully established partial QoS Flows and related resources in the PDU Session2, and sends a secondary base station modification command (SN MODIFICATION COMMAND) message to the SN-gNB 1. The message includes the result of informing SN-gNB1 to continue maintaining S-UE capabilities available after the dual connectivity operation update and that part of the QoS Flows in PDU Session2 have been successfully reflowed to the MN side. Then, the SN-gNB1 deletes part of QoS Flows and related radio resources in the returned PDU Session2, and the control plane, user plane, and transmission resources of the S-NG interface connection, and so on.

After S504: and continuing to maintain the P-RL wireless link between the MN and the P-UE through the RRC reconfiguration message, and continuing to transmit PDU Session1 user service data and partial reflux PDU Session2 user service data. And continuing to maintain the S-RL wireless link between the SN-gNB1 and the S-UE through an RRC reconfiguration message, and continuing to transmit part of the remained PDU Session2 user service data.

Fig. 19 is a schematic structural diagram of a connection device according to an embodiment of the application. The apparatus may be provided in a core network element. As shown in fig. 19, the apparatus may include:

a first sending module 71, configured to send a first indication message to a target secondary base station, where the first indication message includes first indication information that performs a specified operation on a secondary connection between the target secondary base station and a target terminal, where the specified operation includes establishment, addition, modification, or deletion;

A first receiving module 72, configured to receive a first response message from the target secondary base station, where the first response message includes first result information corresponding to the first indication information.

In one embodiment, as shown in fig. 20, the apparatus further comprises:

the second receiving module 73 is configured to receive a first requirement message from a primary base station, where the first requirement message is sent by the primary base station when detecting that the wireless connection states of the target terminal and the multiple base stations change, and the first requirement message includes first requirement information for performing the specified operation on the secondary connection, and the first requirement information includes requirement information for setting up, adding, modifying, deleting or releasing the secondary connection.

In one embodiment, the apparatus further comprises:

and a second sending module 74, configured to send a second indication message to the master base station, where the first result information indicates that the specified operation is successful, where the second indication message includes the first result information and master connection command information corresponding to the first result information.

In one embodiment, the apparatus further comprises:

A third receiving module 75, configured to receive a second requirement message from a target secondary base station, where the second requirement message is sent by the target secondary base station when detecting that the wireless connection states of the target terminal and the multiple base stations change, and the second requirement message includes second requirement information for performing the specified operation on the secondary connection, where the second requirement information includes requirement information for modification, deletion or release of the secondary connection;

a third sending module 76, configured to send a third indication message to the master base station, where the third indication message includes master connection command information corresponding to the second requirement information;

a fourth receiving module 77, configured to receive a second response message from the master base station, where the second response message includes second result information corresponding to the master connection command information.

In an embodiment, the first indication message is a secondary base station establishment request message or a secondary base station addition request message, and the first indication message includes available secondary connection capability and resource information in the target terminal, and user service feature information that needs to be shunted to the target secondary base station.

In one embodiment, the first indication message is a secondary base station modification request message, and the first indication message includes user traffic feature information that needs to be streamed back to the primary base station from the target secondary base station, or user traffic feature information that is re-streamed to the target secondary base station.

In an embodiment, the first indication message is a secondary base station release command message or a secondary base station deletion command message, and the first indication message includes user service feature information remaining on the target secondary base station to be deleted.

In one embodiment, the first demand message establishes a demand message for the secondary base station or adds a demand message to the secondary base station, where the first demand message includes user service feature information that needs to be shunted to the target secondary base station.

In one embodiment, the first requirement message is a secondary base station modification requirement message, and the first requirement message includes user service feature information that needs to be reflowed to the primary base station or user service feature information that needs to be re-streamed to the target secondary base station.

In an embodiment, the first demand message is a secondary base station release demand message or a secondary base station delete demand message, where the first demand message includes user service feature information remaining on the target secondary base station that needs to be deleted.

In one embodiment, the second indication message is a secondary base station establishment command message or a secondary base station addition command message, where the second indication message includes available primary connection capability and resource information in the target terminal, and user service feature information that has been shunted to the target secondary base station.

In one embodiment, the second indication message is a secondary base station modification command message, where the second indication message includes available primary connection capability and resource information in the target terminal, user service feature information that needs to be streamed to the primary base station, or user service feature information that has been streamed to the target secondary base station.

In an embodiment, the second indication message is a secondary base station release command message or a secondary base station deletion command message, where the second indication message includes available primary connection capability and resource information in the target terminal, and remaining user service feature information on the target secondary base station that needs to be reflowed to the primary base station.

In one embodiment, the second requirement message is a secondary base station modification requirement message, and the second requirement information includes user service feature information that needs to be reflowed to the primary base station;

The third indication message is a secondary base station modification request message, and the third indication message comprises available main connection capability and resource information in the target terminal and user service characteristic information which needs to be refluxed to a main base station;

In an embodiment, the second demand message is a secondary base station release demand message or a secondary base station delete demand message, where the second demand message includes user service feature information remaining on the target secondary base station to be deleted;

the third indication message is an auxiliary base station release command message or an auxiliary base station deletion command message, and comprises available main connection capability and resource information in the target terminal, and residual user service characteristic information on the target auxiliary base station which needs to be refluxed to the main base station;

the first indication information is a secondary base station release command message or a secondary base station deletion command message, and the first indication information includes user service characteristic information remained on a target secondary base station to be deleted.

Fig. 21 is a schematic structural diagram of a connection device according to another embodiment of the present application. The apparatus may be arranged in an access network element. As shown in fig. 21, the apparatus may include:

a fifth receiving module 81, configured to receive a first indication message from a core network element, where the first indication message includes first indication information that performs a specified operation on an auxiliary connection between a target auxiliary base station and a target terminal, where the specified operation includes establishment, addition, modification, or deletion;

an execution module 82, configured to execute the specified operation on an auxiliary connection between the target auxiliary base station and the target terminal;

a fifth sending module 83, configured to send a first response message to the core network element, where the first response message includes first result information corresponding to the first indication message.

In one embodiment, as shown in fig. 22, the apparatus further comprises:

a sixth sending module 84, configured to send a first requirement message to the core network element when detecting that the wireless connection states of the target terminal and the plurality of base stations change, where the first requirement message includes first requirement information for performing the specified operation on the secondary connection, and the first requirement message includes a requirement for establishing, adding, modifying, deleting or releasing the secondary connection.

In one embodiment, the apparatus further comprises:

a sixth receiving module 85, configured to receive a second indication message from the core network element, where the second indication message is sent when the core network element indicates that the first result information indicates that the designated operation is successful, and the second indication message includes the first result information and main connection command information corresponding to the first result information.

In one embodiment, the apparatus further comprises:

a seventh sending module 86, configured to send a second requirement message to the core network element when detecting that the wireless connection states of the target terminal and the plurality of base stations change, where the second requirement message includes second requirement information for executing the specified operation on the secondary connection, and the second requirement information includes a requirement for modifying, deleting or releasing the secondary connection.

In one embodiment, the apparatus further comprises:

a seventh receiving module 87, configured to receive a third indication message from the core network element, where the third indication message includes primary connection command information corresponding to the second requirement information;

an eighth sending module 88 is configured to send a second response message to the core network element, where the second response message includes second result information corresponding to the primary connection command information.

In one embodiment, the first requirement message is a secondary base station modification requirement message, and the first requirement message includes user service feature information that needs to be reflowed to the primary base station or re-streamed to the target secondary base station.

In one embodiment, the execution module is further configured to establish an auxiliary connection with the target terminal according to the available auxiliary connection capability and resource information in the target terminal and user service feature information that needs to be shunted to the target auxiliary base station, so as to shunt the user service to the target auxiliary base station, so that the target auxiliary base station continues to carry the transmission.

In one embodiment, the execution module is further configured to delete the user traffic bearer transmission resource that needs to be reflowed from the target secondary base station, or allocate a new bearer transmission resource for the re-forked user traffic.

In one embodiment, the execution module is further configured to delete the remaining user traffic bearer transmission resources from the target secondary base station, and release or delete the target secondary base station.

The functions of each module in each device of the embodiments of the present application may be referred to the corresponding descriptions in the above method embodiments, which are not described herein.

Fig. 23 is a schematic structural diagram of a network device according to an embodiment of the present application, and as shown in fig. 23, a network device 130 according to an embodiment of the present application includes: a memory 1303 and a processor 1304. The network device 130 may also include an interface 1301 and a bus 1302. The interface 1301, memory 1303 and processor 1304 are connected via a bus 1302. The memory 1303 is used for storing instructions. The processor 1304 is configured to read the instructions to execute the technical solution of the method embodiment applied to the access network element, which is similar to the implementation principle and technical effect, and will not be described herein.

Fig. 24 is a schematic structural diagram of a network device according to an embodiment of the present application, and as shown in fig. 24, a network device 140 according to an embodiment of the present application includes: a memory 1403 and a processor 1404. The network device may also include an interface 1401 and a bus 1402. The interface 1401, memory 1403 and processor 1404 are connected via a bus 1402. The memory 1403 is used to store instructions. The processor 1404 is configured to read the instructions to execute the technical solution of the method embodiment applied to the core network element, which is similar to the implementation principle and technical effect, and will not be described herein again.

Fig. 25 is a schematic structural diagram of a communication system according to an embodiment of the present application, as shown in fig. 25, where the system includes: such as the network device 130 of the above embodiment, and the network device 140 of the above embodiment.

The present application provides a storage medium storing a computer program which, when executed by a processor, implements the method in the above embodiments.

The foregoing description is only of the preferred embodiments of the present application, and is not intended to limit the scope of the present application.

In general, the various embodiments of the application may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the application is not limited thereto.

Embodiments of the application may be implemented by a data processor of a mobile device executing computer program instructions, e.g. in a processor entity, either in hardware, or in a combination of software and hardware. The computer program instructions may be assembly instructions, instruction Set Architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages.

The block diagrams of any of the logic flows in the figures of this application may represent program steps, or may represent interconnected logic circuits, modules, and functions, or may represent a combination of program steps and logic circuits, modules, and functions. The computer program may be stored on a memory. The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology. The memory in embodiments of the present application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable EPROM (EEPROM), a flash Memory, or the like. The volatile memory may be random access memory (Random Access Memory, RAM) which acts as an external cache. The RAM may include various forms such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double Data Rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous DRAM (SLDRAM), and Direct RAM (DR RAM). The memory of the systems and methods described herein includes, but is not limited to, these and any other suitable types of memory.

The processors of embodiments of the present application may be of any type suitable to the local technical environment, such as, but not limited to, general purpose computers, special purpose computers, microprocessors, digital signal processors (Digital Signal Processor, DSPs), application specific integrated circuits (Application Specific Integrated Circuit, ASICs), field programmable logic devices (Field-Programmable Gate Array, FGPA) or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or processors based on a multi-core processor architecture. The general purpose processor may be a microprocessor or may be any conventional processor or the like. The above-described processor may implement or perform the steps of the methods disclosed in the embodiments of the present application. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor reads the information in the memory and, in combination with its hardware, performs the steps of the above method.

The foregoing detailed description of exemplary embodiments of the application has been provided by way of exemplary and non-limiting examples. Various modifications and adaptations to the above embodiments may become apparent to those skilled in the art without departing from the scope of the application, which is defined in the accompanying drawings and claims. Accordingly, the proper scope of the application is to be determined according to the claims.

Claims

1. A method of connecting, comprising:

sending a first indication message to a target auxiliary base station, wherein the first indication message comprises first indication information for executing specified operation on auxiliary connection between the target auxiliary base station and a target terminal, and the specified operation comprises establishment, addition, modification, deletion or release of the auxiliary connection; the first indication information comprises user service characteristic information related to the target auxiliary base station;

2. The method as recited in claim 1, further comprising:

receiving a first demand message from a main base station, wherein the first demand message is sent by the main base station under the condition that the wireless connection state of the target terminal and a plurality of base stations is detected to be changed, the first demand message comprises first demand information for executing the appointed operation on the auxiliary connection, and the first demand information comprises demand information for establishing, adding, modifying, deleting or releasing the auxiliary connection.

3. The method according to claim 1 or 2, further comprising:

and if the first result information indicates that the appointed operation is successful, sending a second indication message to the main base station, wherein the second indication message comprises the first result information and main connection command information corresponding to the first result information.

4. The method as recited in claim 1, further comprising:

receiving a second demand message from a target auxiliary base station, wherein the second demand message is sent by the target auxiliary base station under the condition that the wireless connection state of the target terminal and a plurality of base stations is detected to be changed, the second demand message comprises second demand information for executing the appointed operation on the auxiliary connection, and the second demand information comprises demand information for modifying, deleting or releasing the auxiliary connection;

a third indication message is sent to the main base station, wherein the third indication message comprises main connection command information corresponding to the second requirement information;

and receiving a second response message from the main base station, wherein the second response message comprises second result information corresponding to the main connection command information.

5. The method of claim 1, wherein the first indication message is a secondary base station setup request message or a secondary base station addition request message, and the first indication message includes available secondary connection capability and resource information in the target terminal, and user traffic characteristic information that needs to be shunted to a target secondary base station.

6. The method of claim 1, wherein the first indication message is a secondary base station modification request message, and the first indication message includes user traffic characteristic information that needs to be streamed back from the target secondary base station to the primary base station or user traffic characteristic information that is re-streamed back to the target secondary base station.

7. The method of claim 1, wherein the first indication message is a secondary base station release command message or a secondary base station delete command message, and the first indication message includes user traffic feature information remaining on a target secondary base station that needs to be deleted.

8. The method of claim 2, wherein the step of determining the position of the substrate comprises,

the first demand message is a demand message established for the auxiliary base station or a demand message added to the auxiliary base station, and comprises user service characteristic information which needs to be distributed to the target auxiliary base station.

9. The method of claim 2, wherein the step of determining the position of the substrate comprises,

the first demand message is a secondary base station modification demand message, and the first demand message comprises user service characteristic information which needs to be refluxed to a main base station or user service characteristic information which is re-distributed to a target secondary base station.

10. The method of claim 2, wherein the step of determining the position of the substrate comprises,

the first demand message is a secondary base station release demand message or a secondary base station deletion demand message, and the first demand message comprises the residual user service characteristic information on the target secondary base station to be deleted.

11. A method according to claim 3, characterized in that the second indication message is a secondary base station setup command message or a secondary base station addition command message, the second indication message comprising available primary connection capability and resource information in the target terminal and user traffic characteristic information that has been offloaded to the target secondary base station.

12. A method according to claim 3, characterized in that the second indication message is a secondary base station modification command message, the second indication message comprising available primary connection capability and resource information in the target terminal, user traffic feature information that needs to be streamed back to the primary base station, or user traffic feature information that has been streamed to the target secondary base station.

13. A method according to claim 3, characterized in that the second indication message is a secondary base station release command message or a secondary base station deletion command message, the second indication message comprising available primary connection capability and resource information in the target terminal and remaining user traffic characteristic information on the target secondary base station that needs to be refluxed to the primary base station.

14. The method of claim 4, wherein the step of determining the position of the first electrode is performed,

the second demand message is a secondary base station modification demand message, and the second demand message comprises user service characteristic information which needs to be refluxed to the main base station;

15. The method of claim 4, wherein the step of determining the position of the first electrode is performed,

the second demand information is demand information released by the auxiliary base station or demand information deleted by the auxiliary base station, and the second demand information comprises residual user service characteristic information on the target auxiliary base station to be deleted;

16. A method of connecting, comprising:

receiving a first indication message from a core network element, wherein the first indication message comprises first indication information for executing appointed operation on an auxiliary connection between a target auxiliary base station and a target terminal, and the appointed operation comprises establishment, addition, modification, deletion or release of the auxiliary connection; the first indication information comprises user service characteristic information related to the target auxiliary base station;

17. The method as recited in claim 16, further comprising:

and under the condition that the wireless connection states of the target terminal and the plurality of base stations are detected to change, sending a first demand message to the core network element, wherein the first demand message comprises first demand information for executing the appointed operation on the auxiliary connection, and the first demand message comprises the demand for establishing, adding, modifying, deleting or releasing the auxiliary connection.

18. The method as recited in claim 16, further comprising:

receiving a second indication message from the core network element, wherein the second indication message is sent when the core network element indicates that the specified operation is successful in the first result information, and the second indication message comprises the first result information and main connection command information corresponding to the first result information.

19. The method as recited in claim 16, further comprising:

and under the condition that the wireless connection states of the target terminal and the plurality of base stations are detected to change, sending a second demand message to the core network element, wherein the second demand message comprises second demand information for executing the appointed operation on the auxiliary connection, and the second demand information comprises the demand of modifying, deleting or releasing the auxiliary connection.

20. The method as recited in claim 19, further comprising:

receiving a third indication message from the core network element, wherein the third indication message comprises main connection command information corresponding to the second requirement information;

and sending a second response message to the core network element, wherein the second response message comprises second result information corresponding to the main connection command information.

21. The method of claim 16, wherein the first indication message is a secondary base station setup request message or a secondary base station addition request message, and the first indication message includes available secondary connection capability and resource information in the target terminal and user traffic characteristic information that needs to be shunted to a target secondary base station.

22. The method of claim 16, wherein the first indication message is a secondary base station modification request message, and wherein the first indication message includes user traffic characteristic information that needs to be streamed back from the target secondary base station to the primary base station or user traffic characteristic information that is re-streamed back to the target secondary base station.

23. The method of claim 16, wherein the first indication message is a secondary base station release command message or a secondary base station delete command message, and the first indication message includes user traffic characteristic information remaining on a target secondary base station that needs to be deleted.

24. The method of claim 17, wherein the step of determining the position of the probe is performed,

25. The method of claim 17, wherein the step of determining the position of the probe is performed,

26. The method of claim 17, wherein the step of determining the position of the probe is performed,

27. The method of claim 18, wherein the second indication message is a secondary base station setup command message or a secondary base station addition command message, the second indication message including available primary connection capability and resource information in the target terminal and user traffic characteristic information that has been offloaded to a target secondary base station.

28. The method of claim 18, wherein the second indication message is a secondary base station modification command message, and the second indication message includes available primary connection capability and resource information in the target terminal, user traffic feature information that needs to be streamed to a primary base station, or user traffic feature information that has been streamed to a target secondary base station.

29. The method of claim 18, wherein the second indication message is a secondary base station release command message or a secondary base station delete command message, and the second indication message includes available primary connection capability and resource information in the target terminal and remaining user traffic characteristic information on the target secondary base station that needs to be reflowed to the primary base station.

30. The method of claim 20, wherein the step of determining the position of the probe is performed,

31. The method of claim 20, wherein the step of determining the position of the probe is performed,

32. The method according to claim 21, 24 or 27, wherein performing the specifying operation on the secondary connection between the target secondary base station and the target terminal comprises:

And establishing auxiliary connection with the target terminal according to the available auxiliary connection capability and resource information in the target terminal and user service characteristic information needing to be distributed to the target auxiliary base station so as to distribute the user service to the target auxiliary base station, so that the target auxiliary base station continues to bear transmission.

33. The method of claim 22, 25, 28 or 30, wherein performing the specified operation on the secondary connection between the target secondary base station and the target terminal comprises:

deleting the user service bearing transmission resources needing to reflow from the target auxiliary base station or distributing new bearing transmission resources for the re-distributed user service.

34. The method of claim 23, 26, 29 or 31, wherein performing the specified operation on the secondary connection between the target secondary base station and the target terminal comprises:

and deleting the residual user service bearer transmission resources from the target auxiliary base station, and releasing or deleting the target auxiliary base station.

35. A connection device, comprising:

the first sending module is used for sending a first indication message to a target auxiliary base station, wherein the first indication message comprises first indication information for executing specified operation on auxiliary connection between the target auxiliary base station and a target terminal, and the specified operation comprises establishment, addition, modification or deletion; the first indication information comprises user service characteristic information related to the target auxiliary base station;

36. A connection device, comprising:

a fifth receiving module, configured to receive a first indication message from a core network element, where the first indication message includes first indication information that performs a specified operation on an auxiliary connection between a target auxiliary base station and a target terminal, where the specified operation includes establishment, addition, modification, or deletion; the first indication information comprises user service characteristic information related to the target auxiliary base station;

37. A network device, the network device comprising: a processor and a memory;

the memory is used for storing instructions;

the processor is configured to read the instructions to perform the method of any one of claims 1 to 34.

38. A storage medium storing a computer program which, when executed by a processor, implements the method of any one of claims 1 to 34.