CN111629406B

CN111629406B - Method for switching processing, related device, program product and storage medium

Info

Publication number: CN111629406B
Application number: CN201910153521.3A
Authority: CN
Inventors: 曹龙雨; 于益俊
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-02-28
Filing date: 2019-02-28
Publication date: 2021-09-07
Anticipated expiration: 2039-02-28
Also published as: CN111629406A; WO2020173146A1

Abstract

The embodiment of the invention discloses a method for switching processing, related equipment, a program product and a storage medium, wherein the method comprises the following steps: a first user plane network element acquires a first mapping relation, wherein the first mapping relation comprises a corresponding relation between packet filtering information and an identifier of a data radio bearer, the packet filtering information comprises an IP five-tuple, and the data radio bearer is used for bearing a data packet; the first user plane network element receives the address of the second user plane network element and the packet filtering information; and the first user plane network element sends the data packet to the address of the second user plane network element according to the packet filtering information. The continuity of the UE service is effectively ensured.

Description

Method for switching processing, related device, program product and storage medium

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method for handover processing, a related device, a program product, and a storage medium.

Background

A CORE network (CORE) service architecture model of a fifth Generation mobile communication technology (5th-Generation, 5G) is defined by a third Generation partnership project (3 GPP) standard, as shown in fig. 1, where a CORE network control plane function 101 is decomposed into a plurality of service function modules (NFs), the NFs are connected by direct connection, an interaction between the NFs adopts a service interface, a control plane network element 102 is connected to the CORE network control plane function, and a plurality of user plane function network elements, such as the user plane function network element 103 and the user plane function network element 104 shown in fig. 1, are connected to the control plane network element 102.

As shown in fig. 1, in the communication system, the user plane function element is deployed at a position closer to the user equipment 105, for example, the user equipment 105 performs data communication with the user plane function element 103, and when the user equipment 105 moves during a use process, the user plane function element 103 cannot continue to serve the user equipment 105, and the user plane function element 104 can serve the moved user equipment 105, so that the moved user equipment 105 performs data communication with the user plane function element 104.

However, when the user equipment 105 moves frequently, the user plane functional network element may be frequently switched, and in the process of the frequent switching of the user plane functional network element, the data communication may be interrupted very easily, which reduces the efficiency of the data communication.

Disclosure of Invention

The embodiment of the invention provides a method, related equipment, a program product and a storage medium for effectively ensuring uninterrupted switching processing of data transmission in the moving process of user equipment.

A first aspect of an embodiment of the present invention provides a method for handover processing, where the method includes:

a first user plane network element acquires a first mapping relation, wherein the first mapping relation comprises a corresponding relation between packet filtering information and an identifier of a data radio bearer, the packet filtering information comprises an IP five-tuple, and the data radio bearer is used for bearing a data packet;

the first user plane network element receives the address of the second user plane network element and the packet filtering information;

and the first user plane network element sends the data packet to the address of the second user plane network element according to the packet filtering information.

By adopting the method shown in the aspect, when the first user plane network element receives the downlink data packet matched with the packet filtering information, that is, the data packet includes the packet filtering information, the first user plane network element sends the downlink data packet to the second user plane network element identified by the address of the second user plane network element, so that the continuity of the UE service is ensured under the condition that the IP address of the UE is not changed.

Based on the first aspect of the embodiments of the present invention, in an optional implementation manner of the first aspect of the embodiments of the present invention, in order to implement that the first user plane network element sends the data packet to the second user plane network element, the first user plane network element further needs to execute the following steps:

the first user plane network element receives the data packet;

the first user plane network element obtains the packet filtering information included in the data packet.

When the first user plane network element establishes the mapping relationship between the packet filtering information and the address of the second user plane network element, the first user plane network element can analyze the packet filtering information included in the data packet after receiving the data packet, and the first user plane network element can send the data packet to the second user plane network element corresponding to the packet filtering information, so that the continuity of the UE service is ensured under the condition that the IP address of the UE is not changed.

Based on the first aspect of the embodiment of the present invention, in an optional implementation manner of the first aspect of the embodiment of the present invention, the method further includes:

the first user plane network element receives indication information from a control plane network element, where the indication information is used to indicate the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

By adopting the method shown in the present aspect, if the first user plane network element receives the indication information sent by the control plane network element, the first user plane network element can create the mapping relationship between the packet filtering information and the address of the second user plane network element according to the indication of the indication information, so that the first user plane network element can send the data packet to the address of the second user plane network element according to the packet filtering information, thereby ensuring the continuity of the UE service.

A second aspect of the present invention provides a method for handover processing, where the method includes:

the second user plane network element obtains a second mapping relation, the second mapping relation comprises a corresponding relation between the packet filtering information and a data radio bearer, the packet filtering information comprises an IP five-tuple, and the data radio bearer is used for bearing a data packet;

and the second user plane network element sends the address of the second user plane network element to a control plane network element, wherein the address of the second user plane network element is used for the first user plane network element to send the data packet to the second user plane network element according to the packet filtering information.

By adopting the method shown in the present aspect, in the process of switching the UE from the first user plane network element to the second user plane network element, the second user plane network element may create a second mapping relationship, and the second user plane network element may implement the purpose of sending the data packet to the switched UE through the data radio bearer when receiving the data packet based on the second mapping relationship, and in order to ensure that the second user plane network element can successfully receive the data packet, the second user plane network element may send the address of the second user plane network element to the control plane network element, so that the control plane network element forwards the address of the second user plane network element to the first user plane network element, and in the case that the first user plane network element receives the downlink data packet matched with the packet filtering information, the first user plane network element sends the downlink data packet to the network element having the address of the second user plane network element, the method and the device ensure the continuity of the UE service through the first forwarding path under the condition that the IP address of the UE is not changed.

Based on the second aspect of the embodiment of the present invention, in an optional implementation manner of the second aspect of the embodiment of the present invention, the method further includes:

the second user plane network element receiving the data packet from the first user plane network element;

the second user plane network element obtains the packet filtering information included in the data packet;

and the second user plane network element determines to send the data packet through the data radio bearer according to the packet filtering information and the second mapping relation.

By adopting the method of the invention, the second user plane network element can successfully send the data packet to the UE based on the established second mapping relation under the condition that the second user plane network element receives the data packet sent by the first user plane network element, thereby ensuring the continuity of the UE service through the first forwarding path under the condition that the IP address of the UE is not changed.

A third aspect of the embodiments of the present invention provides a method for handover processing, where the method includes:

the control plane network element sends packet filtering information and an identifier of a data radio bearer to a second user plane network element, wherein the packet filtering information comprises an IP quintuple, and the data radio bearer is used for bearing a data packet;

the control plane network element receiving an address of the second user plane network element from the second user plane network element;

the control plane network element sends the address of the second user plane network element and the packet filtering information to the first user plane network element, and the address of the second user plane network element is used for the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

By adopting the method shown in the invention, in the process of switching the UE from the source cell to the target cell, the first user plane network element can create the mapping relation between the packet filtering information and the address of the second user plane network element, and when the first user plane network element receives a downlink data packet matched with the packet filtering information, the first user plane network element sends the downlink data packet to the network element with the address of the second user plane network element through the first forwarding path, so that the continuity of the UE service is ensured through the first forwarding path under the condition that the IP address of the UE is not changed.

Based on the third aspect of the present embodiment, in an optional implementation manner of the third aspect of the present embodiment, the control plane network element sends indication information to the first user plane network element, where the indication information is used to indicate the first user plane network element to send the data packet to an address of the second user plane network element according to the packet filtering information.

By adopting the method shown in the present aspect, the control plane network element determines that the UE is switched to the target cell, and then the control plane network element determines that the first mapping relationship stored in the first user plane network element needs to be changed, and then the control plane network element can send the indication information to the first user plane network element, and then the first user plane network element can create the mapping relationship between the packet filtering information and the address of the second user plane network element according to the indication information, so that the first user plane network element can send the data packet to the address of the second user plane network element according to the packet filtering information, thereby ensuring the continuity of the UE service.

A fourth aspect of the present invention provides a user plane network element, where the user plane network element is a first user plane network element shown in this application, and the user plane network element specifically includes:

an obtaining unit, configured to obtain a first mapping relationship, where the first mapping relationship includes a correspondence between packet filtering information and an identifier of a data radio bearer, the packet filtering information includes an IP quintuple, and the data radio bearer is used for carrying a data packet;

a receiving unit, configured to receive an address of a second user plane network element and the packet filtering information;

and the processing unit is used for sending the data packet to the address of the second user plane network element according to the packet filtering information.

For the method for performing the handover processing, the specific implementation procedure and the beneficial effects of the method for performing the handover processing, please refer to the first aspect.

Based on the fourth aspect of the embodiment of the present invention, in an optional implementation manner of the fourth aspect of the embodiment of the present invention, the receiving unit is further configured to receive the data packet; the obtaining unit is further configured to obtain the packet filtering information included in the data packet.

Based on the fourth aspect of the embodiment of the present invention, in an optional implementation manner of the fourth aspect of the embodiment of the present invention, the receiving unit is further configured to receive indication information from a control plane network element, where the indication information is used to indicate that the first user plane network element sends the data packet to an address of the second user plane network element according to the packet filtering information.

A fifth aspect of the embodiments of the present invention provides a user plane network element, where the user plane network element is a second user plane network element shown in this application, and the user plane network element specifically includes:

an obtaining unit, configured to obtain a second mapping relationship, where the second mapping relationship includes a corresponding relationship between the packet filtering information and a data radio bearer, the packet filtering information includes an IP quintuple, and the data radio bearer is used for carrying a data packet;

a sending unit, configured to send an address of the second user plane network element to a control plane network element, where the address of the second user plane network element is used for the first user plane network element to send the data packet to the second user plane network element according to the packet filtering information.

For the method for performing the handover processing shown in the second aspect, and for a description of a specific execution process and a beneficial effect of the method for performing the handover processing, please refer to the second aspect in detail.

Based on the fifth aspect of the embodiment of the present invention, in an optional implementation manner of the fifth aspect of the embodiment of the present invention, the user plane network element further includes: a receiving unit, configured to receive the data packet from the first user plane network element; the obtaining unit is further configured to obtain the packet filtering information included in the data packet; and a determining unit, configured to determine to send the data packet through the data radio bearer according to the packet filtering information and the second mapping relationship.

A sixth aspect of the present invention provides a control plane network element, including:

a sending unit, configured to send packet filtering information and an identifier of a data radio bearer to a second user plane network element, where the packet filtering information includes an IP quintuple, and the data radio bearer is used to carry a data packet;

a receiving unit, configured to receive an address of the second user plane network element from the second user plane network element;

the sending unit is further configured to send an address of the second user plane network element and the packet filtering information to a first user plane network element, where the address of the second user plane network element is used for the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

The control plane network element in the aspect is used to perform the method for handover processing in the third aspect, and please refer to the third aspect for details of the specific implementation procedure and beneficial effects of the method for handover processing.

Based on the sixth aspect of the present embodiment, in an optional implementation manner of the sixth aspect of the present embodiment, the sending unit is further configured to send indication information to the first user plane network element, where the indication information is used to indicate that the first user plane network element sends the data packet to the address of the second user plane network element according to the packet filtering information.

A seventh aspect of the present application provides a data switching apparatus, where the data switching apparatus has a function of implementing behaviors of network elements in the above method design. The functions can be realized by hardware, or the hardware can also execute corresponding software to realize the hardware or the software comprises one or more modules corresponding to the functions. The modules may be software and/or hardware.

In one possible design, the apparatus may be configured to include a processor and a memory, where the memory has a computer readable program stored therein; the processor is used for implementing the method shown in any one of the above aspects by executing the program in the memory.

An eighth aspect of the present application provides a computer program product for performing the method of any one of the above aspects when the computer program product is executed.

A ninth aspect of the present application provides a computer-readable storage medium having stored thereon instructions for executing the method of any one of the above aspects.

Drawings

Fig. 1 is a schematic structural diagram of a communication system provided in the prior art;

fig. 2 is a schematic diagram of another structure of a communication system provided in the prior art;

FIG. 3 is a diagram of an example control plane protocol stack of an N2 interface provided in the prior art;

FIG. 4 is a diagram of an example user plane protocol stack of an N3 interface provided by the prior art;

fig. 5 is a schematic structural diagram of an embodiment of a communication system according to the present invention;

fig. 6 is a schematic structural diagram of an embodiment of a protocol stack of a user plane network element according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

FIG. 8 is a flowchart illustrating an embodiment of a handover processing method according to the present invention;

fig. 9 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

FIG. 10 is a flowchart illustrating an embodiment of a method for handover processing according to the present invention;

fig. 11 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 12 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

fig. 13 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 14 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

fig. 15 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

FIG. 16 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 17 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

fig. 18 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 19 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

FIG. 20 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 21 is a schematic structural diagram of another embodiment of a communication system according to an embodiment of the present invention;

fig. 22 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 23 is a flowchart illustrating steps of another embodiment of a method for handover processing according to an embodiment of the present invention;

fig. 24 is a schematic structural diagram of an embodiment of a user plane network element according to the present invention;

fig. 25 is a schematic structural diagram of another embodiment of a user plane network element according to an embodiment of the present invention;

fig. 26 is a schematic structural diagram of an embodiment of a control plane network element according to the present invention;

fig. 27 is a schematic structural diagram of an embodiment of a data switching apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application. In the present application, "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

In order to better understand the method shown in this embodiment, first, the following specifically describes the structure of the communication system in the prior art:

as shown in fig. 2, in the 5G mobile network architecture shown in fig. 2, a control plane function and a forwarding plane function of a mobile gateway are decoupled, and the separated control plane function is merged with a Mobility Management Entity (MME) of a third generation partnership project (3 GPP) conventional control network element into a unified control plane (control plane). A User Plane Function (UPF) network element can implement a Serving Gateway (SGW) and a packet data network gateway (PGW) User plane functions (SGW-U and PGW-U). Further, the unified control plane network element may be decomposed into an access and mobility management function (AMF) network element and a Session Management Function (SMF) network element.

Optionally, the core network control plane Function 201 shown in fig. 2 further includes functional modules such as an authentication service Function (AUSF), and may further include an Application Function (AF), a Unified Data Management (UDM), a Policy Control Function (PCF), an NF storage Function (NRF), and a network open Function (NEF).

The terminal device involved in the system is not limited to the 5G network, and includes: the system comprises a mobile phone, an internet of things device, an intelligent household device, an industrial control device, a vehicle device and the like. The Terminal device may also be referred to as a User Equipment (UE), a Mobile Station (Mobile Station), a Mobile Station (Mobile), a Remote Station (Remote Station), a Remote Terminal (Remote Terminal), an Access Terminal (Access Terminal), a Terminal device (User Terminal), and a User Agent (User Agent), which are not limited herein. The terminal device may be an automobile in Vehicle-to-Vehicle (V2V) communication, a device in device communication, or the like.

The RAN202 is an apparatus for providing wireless communication functions for UEs. The RAN202 may include various forms of base stations, such as: macro base stations, micro base stations (also referred to as small stations), relay stations, access points, etc. In systems using different radio access technologies, names of devices having a base station function may be different, for example, in an LTE system, the device is called an evolved node B (eNB or eNodeB), and in a third generation (3G) system, the device is called a node B (node B). In a new generation system, called gnb (gnnodeb).

Optionally, the AMF network element involved in the system may be responsible for registration of the terminal device, mobility management, tracking area update process, and the like. The AMF network element may also be referred to as an AMF device or an AMF entity.

Optionally, the UDM network element involved in the system can store subscription data of the user. For example, the subscription data of the user includes subscription data related to mobility management and subscription data related to session management. The UDM network element may also be referred to as a UDM device or a UDM entity.

Optionally, the SMF network element involved in the present system may be responsible for session management of the terminal device. For example, session management includes selection of a user plane device, reselection of a user plane device, IP address allocation, quality of service (QoS) control, and establishment, modification, or release of a session, among others.

Optionally, the 5G communication system further includes a Network Function storage Function (NRF) Network element. The network element is capable of providing a service discovery function. Optionally, the NRF network element may further be configured to maintain information of a network function network element that is valid in the core network. Optionally, the NRF network element may further be configured to maintain services supported by the network functional network element in the core network.

Optionally, the UPF network element may implement functions of forwarding, counting, and detecting the user packet. A UPF network element may also be referred to as a UPF device or UPF entity.

Optionally, the PCF network element includes policy control and flow-based charging control functions. For example, the PCF network element may implement a user subscription data management function, a policy control function, a charging policy control function, QoS control, and the like. A PCF network element may also be referred to as a PCF entity or PCF device.

Based on the structural example of the core network control plane function shown in fig. 2, the interaction between NFs adopts a service-oriented interface, for example, interface Nnef is a service-based interface provided by NEF, interface Nnrf is a service-based interface provided by NRF, interface Npcf is a service-based interface provided by PCF, interface numm is a service-based interface provided by UDM, interface Naf is a service-based interface provided by AF, interface Namf is a service-based interface provided by AMF, and interface Nsmf is a service-based interface provided by SMF.

The core network control plane function 201 is connected to a Radio Access Network (RAN) 202, an interface between the core network control plane function 201 and the RAN202 is an N2 interface, an N2 interface is a reference point between the RAN202 and the AMF, and an N2 interface does not support servitization.

The control plane protocol stack of the N2 interface is described below in conjunction with fig. 3:

for the uplink control plane signaling, the RAN202 side sequentially processes by a control plane layer PDCP-C layer and a Radio Resource Control (RRC) layer of a Packet Data Convergence Protocol (PDCP), forwards the processed signaling to an NGAP (Application protocol) layer, forwards the processed signaling to a Stream Control Transmission Protocol (SCTP) layer after processing by the NGAP layer, and sends the processed signaling to the AMF through an N2 interface after processing by the SCTP layer, and sequentially processes by an SCTP layer and an NGAP layer of the AMF side.

The user plane protocol stack of the N3 interface is described below in conjunction with that shown in fig. 4:

for uplink user plane data, the RAN202 side sequentially processes by a user plane PDCP-U layer and a Service Data Adaptation Protocol (SDAP) layer of the PDCP, then forwards the processed signaling to a general packet radio service tunneling protocol user plane (GTPU) layer, and after completing the GTPU layer, sequentially processes by an Internet Protocol (IP) layer, a Media Access Control (MAC) (L2) layer and a physical layer (L1) interconnected between networks, and forwards the signaling to the UPF203 through an N3 interface, and then processes by the GTPU layer on the UPF203 side, a user data packet protocol (UDP) layer, an IP layer, an L2 layer, and an L1 layer.

It can be seen that, with the communication system shown in the prior art, for the user plane, both the SDAP layer and the PDCP-U layer on the RAN side need to support GTPU/UDP protocol processing, and perform data forwarding with the UPF203 through the N3 interface, so that the GTPU protocol processing of the N3 interface results in a large delay in data forwarding and a low processing efficiency.

The following describes, by way of example, a structure of the communication system provided in the present application with reference to the embodiment shown in fig. 5, and the communication system shown in the present embodiment can avoid GTPU/UDP protocol processing, thereby reducing a time delay of data forwarding and improving processing efficiency.

As shown in fig. 5, the communication system shown in this embodiment includes a core network control plane function 501, and a detailed description of the core network control plane function 501 is shown in fig. 2, which is not limited in this embodiment.

For example, the core Network control plane function 501 shown in this embodiment is connected to a Radio Network Management Function (RNMF) 502 through an R2 interface, the RNMF502 is connected to a user plane Network element 503 through an E1 interface, the RNMF502 is connected to a Distributed Unit (DU) 505 through an F1-C interface, the DU505 is connected to a User Equipment (UE) 506, and the user plane Network element 503 may also be connected to a data Network element (datan Network, DN)504 through an N6 interface.

The communication system shown in the embodiment can realize the fusion of a control plane and a user plane;

for the control plane fusion, since the NFs included in the RNMF502 and the core network control plane function 501 in this embodiment are mutually called in a service manner, and the RAN and the core network control plane function can be fused when the RNMF502 is connected to the radio access network control plane function network element 504.

For the convergence of the user plane, compared with the prior art, the user plane network element 503 shown in this embodiment is a network element formed by removing a user plane N3 interface and GTPU/UDP protocol processing thereof from a RAN side and a UPF side shown in the prior art, and a protocol stack of the user plane network element 503 can be seen in fig. 6;

as shown in fig. 6, the user plane network element 503 includes an SDAP layer, a PDCP-U layer, an IP layer, an L2 layer, and an L1 layer, as shown in fig. 5 and 6, in case that the user plane network element 503 receives a downstream packet sent by the DN507, the downlink packets can be forwarded one hop to the SDAP layer and PDCP-U layer of the RAN user plane, it can be seen that, with the communication system shown in this embodiment, because the user plane network element 503 included in the communication system has deleted the user plane N3 interface and its GTPU/UDP protocol processing, the user plane network element 503 does not need to perform GTPU protocol processing, so that the downlink data packet can be forwarded to the SDAP layer and the PDCP-U layer in one hop, the data forwarding delay is reduced, and the function fusion and the service unified communication between the user plane network element 503 and the core network control plane function 501 are realized.

In this embodiment, the user plane network element may be closer to the user equipment in deployment, so that in a process of moving the user equipment, a probability of changing the user plane network element serving the user equipment may increase, and in a case of frequent movement of the user equipment, frequent switching of the user plane network element may be caused, and further, in a process of frequent movement of the user equipment, service interruption of the user equipment may be caused due to untimely switching of the user plane network element, so that efficiency of data transmission is reduced.

Based on the above-mentioned specific description of the user plane network element, the following describes the structure of the communication system for implementing the user plane network element handover with reference to fig. 7:

as shown in fig. 7, please refer to the above description for a specific description of a core network control plane function 701, which is not described in detail specifically, and this embodiment takes a network element before execution as a control plane network element 702 for example to perform an exemplary description, where the control plane network element may be an RNMF shown in fig. 5, or may be a PDCP-C, and is not limited in this embodiment specifically;

as shown in the structure of the communication system shown in fig. 7, before the handover, the UE705 may interact with the control plane network element 702 through the first DU704, and after the handover, the UE705 may interact with the control plane network element 702 through the second DU 708; and the DN that the UE705 needs to access before the switching is the first DN706, that is, the first DN706 can send a downlink data packet to the UE705 through the first user plane network element 703, and after the switching, the DN that the UE705 needs to access is switched to the second DN716, that is, for the switched UE705, the second DN716 sends the downlink data packet to the UE705 through the second user plane network element 707. Fig. 7 illustrates an example where one user plane cell is connected to one DN, in other examples, one user plane cell may be connected to multiple DNs, and a specific description is not limited in this embodiment.

Based on the communication system shown in fig. 7, the following describes a specific implementation procedure of the method for handover processing shown in this embodiment with reference to fig. 8:

step 801, a first user plane network element obtains a first mapping relationship.

For example, the first mapping includes a correspondence of packet filtering information and an identification of the data radio bearer. Wherein the packet filtering information includes an IP quintuple. Wherein, the Data Radio Bearer (DRB) is used for carrying data packets.

For example, a first user plane network element stores a first mapping relationship.

For example, after receiving the data packet, the first user plane network element determines that the IP quintuple included in the data packet is the same as the IP quintuple in the first mapping relationship, and then the first user plane network element may determine a data radio bearer based on the first mapping relationship and send the data packet to the UE through the data radio bearer.

The first user plane network element shown in this embodiment is the first user plane network element 703 shown in fig. 7, and the UE is the UE705 shown in fig. 7.

Step 802, the first user plane network element receives the address and packet filtering information of the second user plane network element.

For example, the control plane network element determines that a user plane network element serving the UE is switched from a first user plane network element to a second user plane network element, and the control plane network element obtains an address and packet filtering information of the second user plane network element. And the control plane network element sends the address of the second user plane network element and the packet filtering information to the first user plane network element.

The second user plane network element shown in this embodiment is the second user plane network element 707 shown in fig. 7, and the control plane network element is the control plane network element 702 shown in fig. 7.

Step 803, the first user plane network element sends a data packet to the address of the second user plane network element according to the packet filtering information.

For example, when the first user plane network element receives the address of the second user plane network element and the packet filtering information, the first user plane network element creates a corresponding relationship between the packet filtering information and the address of the second user plane network element. When the first user plane network element receives the data packet including the packet filtering information, the first user plane network element can determine the address of the second user plane network element corresponding to the packet filtering information according to the stored corresponding relation, and the first user plane network element can send the data packet to the address of the second user plane network element, so that the user plane network element identified by the address of the second user plane network element can receive the data packet sent by the first user plane network element.

By using the method shown in this embodiment, in the process of switching the UE to the second user plane network element, the first user plane network element may create a mapping relationship between the packet filtering information and the address of the second user plane network element, and when the first user plane network element receives a data packet matching the packet filtering information, the first user plane network element sends the data packet to the address of the second user plane network element corresponding to the packet filtering information, and sends the data packet to the user plane network element having the address of the second user plane network element.

For better understanding of the method shown in the present application, the following exemplary specific procedures for performing the method shown in the present application are described for different communication system configurations:

in the following different embodiments, shown in fig. 9 and 10, first, referring to fig. 9 and 10, in the embodiment shown in fig. 9 and 10, a control plane network element for performing handover is exemplarily described as a first radio network management function RNMF, where the method shown in this embodiment specifically includes:

step 1001, the UE transmits a measurement report to the first RNMF.

In the measurement report shown in this embodiment, the measurement report generated after the UE measures the source cell where the UE resides specifically includes a measurement identifier ID, a measurement result of the source cell, and a measurement result of the neighboring cell. The present embodiment does not limit the specific content included in the measurement report.

As shown in the structure of the communication system shown in fig. 9, the UE901 reports the measurement report to the first RNMF905 sequentially through the first DU902, the first PDCP-C903, and the first RRC904, where the first PDCP-C903 and the first RRC904 are both connected to the first RNMF905, and a specific description of the first RNMF may refer to the description shown in fig. 5, which is not specifically described herein, and this embodiment describes, by taking an example that the core network control plane function includes an AMF, an SMF, and a UDM, and in a specific application, in a process of executing the method shown in this embodiment, the number and the type of NFs included in the core network control plane function are not limited.

Step 1002, the first RNMF transmits a handover instruction to the first RRC.

The first RNMF determines, according to the received measurement report, a target cell, where the target cell is a cell to which the UE needs to be handed over, and the first RNMF determines, according to an identifier (target ID) of the target cell, whether the target cell is within a service range of the first RNMF, and optionally, the first RNMF may be preset with a service list, where the service list includes identifiers of cells that can be served by the first RNMF, in this step, if the first RNMF determines that the identifier of the target cell is located in the service list, the first RNMF determines that the target cell is within the service range of the first RNMF, and if the identifier of the target cell is not located in the service list, the first RNMF determines that the target cell is not within the service range of the first RNMF.

In this embodiment, taking the target cell within the service range of the first RNMF as an example, if the target cell is within the service range of the first RNMF, the AMF, the SMF, and the like for serving the UE need not be changed.

In this embodiment, the first RNMF determines a first RRC, where the first RRC is an RRC currently used for serving the UE, and then sends handover indication information to the first RRC, where the handover indication shown in this embodiment is used to indicate that the first RRC initiates an HO request.

Step 1003, the first RRC sends the handover request to the first RNMF.

And under the condition that the first RRC receives the switching indication, the first RRC sends a switching request HO request to the first RNMF according to the switching indication, wherein the HO request carries information such as the target ID, the user equipment identifier (UE ID), the globally unique AMF ID (GUAMI), the user equipment context (UE context) and the like.

Step 1004, the first RNMF sends a handover request to the second RRC.

The first RNMF determines a second RRC according to the received target ID, where the second RRC is an RRC capable of serving the target cell, that is, the second RRC determined by the first RNMF is capable of serving the UE camped in the target cell after handover, and both the first RRC904 and the second RRC906 belong to a service range of the first RNMF905 as shown in fig. 9.

And when the first RNMF determines the second RRC, the first RNMF sends a handover request to the second RRC, wherein the handover request sent to the second RRC by the first RNMF carries a second Data Network Name (DNN), second indication information (selection indication), a quality of service configuration file (QoS profile) and Packet filter (Packet filter) information corresponding to the QoS profile.

The second DNN is used to identify a name of a second DN that the UE needs to access after the handover, and continuing to take the example shown in fig. 9 as an example, the DN that the UE901 needs to access before the handover is the first DN911, that is, the first DN911 can send a downlink data packet to the UE901 through the first user plane network element 908, and after the handover, the DN that the UE901 needs to access is switched to the second DN912, that is, for the UE901 after the handover, the second DN912 sends the downlink data packet to the UE901 through the second user plane network element 909. Fig. 9 illustrates an example where one user plane cell is connected to one DN, in other examples, one user plane cell may be connected to multiple DNs, and a specific description is not limited in this embodiment.

The second indication information is an operation indication sent by the first RNMF to the second PDCP entity, where the second indication information is used to indicate the second PDCP entity to determine a second user plane network element, and for a specific description of the second user plane network element, please refer to the specific description of the user plane network element shown in fig. 5, which is not repeated in this embodiment. The second user plane network element determined by the second PDCP entity is configured to serve the UE after handover, and a value of the second indication information is not limited in this embodiment as long as the second PDCP entity that receives the second indication information can perform a relevant operation for determining the second user plane network element, for example, the value of the second indication information shown in this embodiment may be a conversion UP type.

The QoS profile is QoS parameter information sent by the SMF to the first RNMF, and optionally, the QoS profile may include at least one of the following: allocation Retention Priority (ARP), Guaranteed stream Bit Rate (GFBR), Maximum stream Bit Rate (MFBR), Maximum Packet Loss Rate (MPLR), and the like. The first RNMF further receives the packet filtering information corresponding to the quality of service profile from the SMF. After receiving the qos configuration file and the corresponding packet filtering information sent by the SMF, the first RNMF may set the qos configuration file and the corresponding packet filtering information in the handover request.

The packet filtering information is explained below:

the SMF acquires the packet filtering information from the first user plane network element and forwards the packet filtering information to the first RNMF, wherein the packet filtering information comprises an IP five-tuple, and specifically comprises a source IP address, a source port, a destination IP address, a destination port and a transport layer protocol. And a first mapping relationship between the packet filtering information and the data radio bearer has been created on the first user plane network element, taking fig. 9 as an example, before the UE901 is not handed over, the first user plane network element 908 receives a downlink data packet from the first ND911 through an N6 interface, the first user plane network element 908 may match the packet filtering information stored by the first user plane network element 908 based on IP quintuple information in the downlink data packet, if the IP quintuple in the downlink data packet is consistent with the packet filtering information, the first user plane network element 908 may determine a DRB corresponding to the packet filtering information according to the first mapping relationship created in advance, and the first user plane network element may forward the downlink data packet to the UE through the DRB corresponding to the packet filtering information.

Step 1005, the second RRC sends a PDU session resource setup message to the second PDCP-C.

In this embodiment, after the second RRC receives the handover request, the second RRC may establish an RRC context for the UE according to the handover request, and the second RRC allocates a Data Radio Bearer (DRB) Identifier (ID) for a data connection (PDU Session) of the UE, where the PDU Session is used to establish a service for exchanging PDU packets between the UE and the second DU, that is, is used to establish a data transmission channel between the UE and the second DU.

The second RRC selects a second PDCP-C capable of serving the UE after handover based on the target ID, and sends a PDU session resource setup (PDU session setup) message to the determined second PDCP-C, where the PDU session resource setup message carries parameter information such as the DRB ID, the second DNN, the selection indication, the QoS profile and the corresponding packet filtering information thereof, and a detailed description of each parameter is described in the above, which is not repeated.

Step 1006, the second PDCP-C sends a context setup request message to the second user plane network element.

In a case that the second PDCP entity receives the session resource establishment message sent by the second RRC, the second PDCP entity activates a security context, and selects a user plane network element according to the indication of the selection indication in the message, in this embodiment, an example is given in which the user plane network element selected by the second PDCP entity according to the indication of the selection indication is the second user plane network element, and a detailed description of the second user plane network element is described in the foregoing, which is not described in detail.

Optionally, the second PDCP-C may further refer to the second DNN to select the second user plane network element, so that the second user plane network element selected by the second PDCP-C can serve the second DNN service, and further optionally, the second PDCP-C may further refer to location information of the UE to select the second user plane network element, where the location information of the UE may be a target cell to which the UE is to be handed over, so that the second user plane network element can serve the UE residing in the target cell, and further optionally, the second PDCP-C may further refer to a Radio Access Type (RAT) to select the second user plane network element, so that the second user plane network element selected by the second PDCP-C can support the RAT.

And under the condition that the second PDCP-C selects the second user plane network element, the second PDCP-C sends the context establishment request message to the second user plane network element, wherein the context establishment request message carries the DRB id, the QoS profile and the corresponding packet filtering information thereof.

Step 1007, the second user plane network element sends a context setup response message to the second PDCP-C.

In a case that the second user plane network element receives the context setup request message, the second user plane network element activates a user plane security context and related configurations, such as a configuration related to security, a configuration related to encryption and decryption of a signaling, and the like, which is not limited in this embodiment.

And the second user plane network element creates a second mapping relationship according to the DRB id and the packet filtering information carried by the context establishment request message, wherein the second mapping relationship comprises the packet filtering information and a mapping relationship of a data radio bearer identified by the DRB id.

The context setup response (context setup response) message sent by the second user plane network element carries the DRB id and an address of the second user plane network element, for example, the address of the second user plane network element shown in this embodiment is an address of the second user plane network element, and for example, the address of the second user plane network element may be an IP address of the second user plane network element and/or a Media Access Control (MAC) address of the second user plane network element. The address of the second user plane network element is used for establishing a first forwarding path for data forwarding between the first user plane network element and the second user plane network element in the process of switching the UE, so that the first user plane network element can forward the data packet to the second user plane network element through the first forwarding path, thereby effectively avoiding the situation of the service terminal of the UE caused by untimely switching of the user plane network element.

Step 1008, the second PDCP-C sends a signaling message to the second DU.

The signaling message shown in this embodiment indicates that the second DU creates a PDU session with the UE, and the second DU may establish a data transmission channel between the UE and the second DN according to the signaling message.

Step 1009, the second PDCP-C sends a PDU session resource setup response to the second RRC.

In this embodiment, after the second PDCP entity determines that the second DU completes the configuration of the PDU session, the second PDCP entity may send a PDU session resource setup response (PDU session resource setup response) to the second RRC. The PDU Session resource setup response is used to indicate that the PDU Session configuration is completed, and the PDU Session resource setup response may also carry a PDU Session ID and an address of the second user plane network element.

Step 1010, the second RRC sends a handover request confirm message to the first RNMF.

And after receiving the PDU session resource setup response, the second RRC sends a handover Request acknowledgement (HO Request Ack) message to the first RNMF, wherein the HO Request Ack message carries the PDU session ID and the address of the second user plane network element.

In step 1011, the first RNMF transmits a handover request confirm message to the first RRC.

The first RNMF may send the HO Request Ack message to the first RRC, where the HO Request Ack message carries parameters such as first indication information (operation indication), an address of the second user plane network element, and the packet filtering information, and the first indication information is used to indicate the first user plane network element to create a mapping relationship between the address of the second user plane network element and the packet filtering information.

Step 1012, the first RRC sends a handover command to the first PDCP-C.

When the first RRC determines that the UE has been handed over to the target cell, the first RCC may send the handover command (HO command) to the first PDCP-C, where the HO command carries the first indication information, the address of the second user plane network element, and the packet filtering information.

Step 1013, the first PDCP-C sends a context modification request message to the first user plane network element.

The Context modification request (Context modification request) message carries the first indication information, the address of the second user plane network element, and the packet filtering information, and for specific descriptions of the first indication information, the address of the second user plane network element, and the packet filtering information, please refer to the above description, which is not repeated.

Step 1014, the first user plane network element receives the context modification request message.

Wherein the first user plane network element may modify the first mapping relationship stored in the first user plane network element according to the first indication information included in the context modification request message, for example, before the UE is handed over, the first user plane network element has created a first mapping relationship between the packet filtering information and the DRB, and when the first user plane network element receives the first indication information, the first user plane network element modifies the mapping relationship between the packet filtering information and the DRB into the mapping relationship between the packet filtering information and the address of the second user plane network element, and when the first user plane network element modifies the mapping relationship between the packet filtering information and the DRB into the mapping relationship between the packet filtering information and the address of the second user plane network element, if the first user plane network element receives a downlink data packet, and the first user plane network element determines that the IP quintuple information in the downlink data packet is the same as the packet filtering information, the first user plane network element can determine the address of a second user plane network element corresponding to the packet filtering information, and the first user plane network element forwards the downlink data packet to the address of the second user plane network element.

Step 1015, the first user plane network element sends a context modification response message to the first PDCP-C.

The context modification response message is used to indicate that the first user plane network element has successfully created the first mapping relationship.

Step 1016, the first PDCP-C sends a handover command to the UE.

The handover command (HO command) is used to instruct the UE to perform RRC reconfiguration so as to synchronize the UE to the target cell, taking fig. 9 as an example, after the first PDCP-C903 sends the handover command to the first DU902, the first DU902 may forward the handover command to the UE901, and the UE901 may perform RRC reconfiguration so as to connect the UE901 to the target cell, and the UE901 connected to the target cell may send uplink data to the second user plane network element 909 through the second DU 910.

Step 1017, the UE sends a handover complete confirmation message to the first RNMF.

In this embodiment, when the UE determines that the UE is connected to the target cell, the UE may sequentially send a confirmation message to the first RNMF via the second DU, the second PDCP-C, and the second RRC. The handover complete confirm message is used to indicate to the first RNMF that the UE has been handed over to the target cell.

After receiving the handover completion confirm message, the first RNMF updates context information of the AMF and the SMF, thereby indicating, at a core network control plane function side, that the UE has been handed over to the target cell.

By using the method shown in this embodiment, in a process of switching the UE to a target cell by the first RNMF, the first user plane network element may create a mapping relationship between packet filtering information and an address of the second user plane network element, and when the first user plane network element receives a downlink data packet matched with the packet filtering information, the first user plane network element sends the downlink data packet to the second user plane network element having the address of the second user plane network element, so that the creation of a forwarding path between the first user plane network element and the second user plane network element is realized without changing an IP address of the UE, and continuity of a UE service is ensured through the first forwarding path.

Based on the UE being handed over to the target cell as shown in fig. 10, how to transmit uplink data packets and downlink data packets after the UE is handed over to the target cell is described with reference to fig. 11;

step 1101, the first user plane network element receives a downlink data packet.

Continuing with the example shown in fig. 9, the first user plane network element 908 receives downstream packets from the first DN over an N6 interface.

Step 1102, the first user plane network element determines a first forwarding path.

As can be seen from the embodiment shown in fig. 10, the first user plane network element stores a first mapping relationship between packet filtering information and an address of a second user plane network element, and when the first user plane network element receives the downlink data packet, the first user plane network element may obtain IP quintuple information in the downlink data packet and obtain packet filtering information that is the same as the IP quintuple information in the downlink data packet, and the first user plane network element may determine, according to the stored first mapping relationship, an address of the second user plane network element corresponding to the packet filtering information.

Step 1103, the first user plane network element sends the downlink data packet to the second user plane network element.

The first user plane network element may send the downlink data packet to the second user plane network element having the address of the second user plane network element.

And step 1104, the second user plane network element sends the downlink data packet to the UE.

In this embodiment, the second user plane network element has created a second mapping relationship between packet filtering information and a target DRB, and when the second user plane network element receives a downlink data packet, the second user plane network element may obtain an IP quintuple included in the downlink data packet and obtain the packet filtering information corresponding to the IP quintuple information in the downlink data packet, and may obtain the target DRB corresponding to the packet filtering information, and the second user plane network element may send the data packet to the UE through the target DRB.

The above steps show how downlink data packets are sent to the UE that has handed over to the target cell, and the following steps show how uplink data packets are sent to the second DN.

Step 1105, the UE sends the uplink data packet to the second DU.

In this embodiment, when the UE is connected to a target cell, as shown in fig. 9 as an example, when the UE901 has an uplink data packet to send, the UE901 may send the uplink data packet to the second DU 910.

Step 1106, the second DU sends the uplink data packet to the second user plane network element.

Step 1107, the second user plane network element sends the uplink data packet to the second DN.

In this embodiment, with continuing to refer to fig. 9, when the second user plane network element 909 receives the uplink data packet sent by the UE901, the second user plane network element 909 may send the uplink data packet to the second DN912 through an N6 interface, so as to implement sending of the uplink data packet.

By adopting the method shown in this embodiment, if the first user plane network element receives a downlink data packet, the first user plane network element can directly forward the downlink data packet to the second user plane network element through the first forwarding path according to the created first mapping relationship between the packet filtering information and the address of the second user plane network element, thereby effectively ensuring the continuity of the UE service and improving the efficiency of data transmission.

In the following, with reference to fig. 12 and fig. 13, another embodiment of the method for performing a handover process in the present application is described, where in the embodiment shown in fig. 12 and fig. 13, a control plane network element performing a handover is exemplarily described as a second radio access network control plane functional network element;

as shown in the communication system shown in fig. 12, relative to the communication system shown in fig. 9, the communication system shown in fig. 12 does not include an RNMF, the first RRC and the second RRC shown in fig. 12 are both functionally connected to a core network control plane, and the first RRC and the second RRC are connected to each other, for detailed description of other network elements shown in fig. 12, please refer to the foregoing embodiment, which is not specifically described again, and the method shown in this embodiment specifically includes:

step 1301, the UE reports to the first RRC measurement.

For a detailed description of the measurement report shown in this embodiment, please refer to fig. 10, which is not repeated in detail, and referring to fig. 12, the UE1201 reports the measurement report to the first RRC1204 sequentially through the first DU1202 and the first PDCP-C1203.

Step 1302, the first RRC sends a handover request to the second RRC.

In this embodiment, the first RRC may determine a target cell according to the received measurement report, where the target cell is a cell to which the UE is to be handed over and an identifier (target ID) of the target cell. The first RRC acquires the identity (UE id) and the GUAMI information of the UE requesting the switching.

The first RRC determines a second RRC according to the determined target ID, where the second RRC is an RRC capable of serving the target cell, that is, the second RRC determined by the first RRC is capable of serving the UE residing in the target cell after the handover, and as shown in fig. 12, the second RRC1206 is an RRC determined by the first RRC1204 and capable of serving the UE1201 after the handover.

And sending, by the first RRC, a handover request to the second RRC when the first RRC determines the second RRC, where the handover request sent by the first RRC to the second RRC carries a second Data Network Name (DNN), second indication information (selection indication), a quality of service configuration file (QoS profile), and Packet filter (Packet filter) information corresponding to the QoS profile. For a detailed description of each parameter included in the handover request, please refer to the embodiment shown in fig. 10, which is not described in detail in this embodiment.

And step 1303, the second RRC sends a PDU session resource establishment message to the second PDCP-C.

Step 1304, the second PDCP-C sends a context setup request message to the second user plane network element.

Step 1305, the second user plane network element sends a context setup response message to the second PDCP-C.

Step 1306, the second PDCP-C sends a signaling message to the second DU.

Step 1307, the second PDCP-C sends a PDU session resource setup response to the second RRC.

For the specific execution process of step 1303 to step 1307 shown in this embodiment, please refer to step 1005 to step 1009 shown in fig. 10, which is not described in detail in this embodiment.

Step 1308, the second RRC sends a handover request confirm message to the first RRC.

And after receiving the PDU session resource setup response, the second RRC sends a handover Request acknowledgement (HO Request Ack) message to the first RRC, wherein the HO Request Ack message carries the PDU session ID and the address of the second user plane network element. The HO Request Ack message carries parameters such as first indication information (operation indication), an address of the second user plane network element, the packet filtering information, and the like, where the first indication information is used to indicate the first user plane network element to create a mapping relationship between the address of the second user plane network element and the packet filtering information.

Step 1309, the first RRC sends a handover command to the first PDCP-C.

Step 1310, the first PDCP-C sends a context modification request message to the first user plane network element.

Step 1311, the first user plane network element receives the context modification request message.

Step 1312, the first user plane network element sends a context modification response message to the first PDCP-C.

Step 1313, the first PDCP-C sends a handover command to the UE.

Step 1314, the UE sends a handover complete confirm message to the first RRC.

In this embodiment, when the UE determines that the UE is connected to the target cell, the UE may sequentially send a confirmation message to the first RRC through the second DU, the second PDCP-C, and the second RRC. The handover complete confirm message is used to indicate to the first RRC that the UE has been handed over to the target cell.

After receiving the handover completion confirm message, the first RRC updates context information of the AMF and the SMF, so as to indicate, on a core network control plane function side, that the UE has been handed over to the target cell.

Please refer to step 1012 to step 1017 shown in fig. 10 for the specific execution process of step 1309 to step 1314 shown in this embodiment, which is not described in detail herein.

By using the method shown in this embodiment, in the process of switching the UE to the target cell by the second RRC, the first user plane network element may create a mapping relationship between packet filtering information and an address of the second user plane network element, and when the first user plane network element receives a downlink data packet matched with the packet filtering information, the first user plane network element sends the downlink data packet to the second user plane network element having the address of the second user plane network element through the first forwarding path, so that the creation of the forwarding path between the first user plane network element and the second user plane network element is realized without changing the IP address of the UE, and the continuity of the UE service is ensured through the first forwarding path.

Based on fig. 13, in a case that the first user plane network element may create a mapping relationship between the packet filtering information and an address of the second user plane network element, a specific process how the UE implements sending of the uplink data packet and a specific process how the UE implements a structure of the downlink data packet may refer to the embodiment shown in fig. 9, which is not described in detail.

In the following, with reference to fig. 14 and fig. 15, another embodiment of the method for handover processing in the present application is described, in the embodiment shown in fig. 14 and fig. 15, a control plane network element performing handover is exemplarily described as a second radio network management function RNMF, and first, a structure of the communication system provided in fig. 14 is described: the communication system shown in this embodiment includes two RNMF, that is, a first RNMF1401 and a second RNMF1402, and for the description of the first RNMF1401 and the second RNMF1402, refer to the description of the RNMF shown in fig. 5, which is not described in detail specifically, and refer to the description of each network element connected to the second RNMF1402, which is shown in fig. 9, which is not described specifically, the communication system shown in this embodiment further includes a packet routing distribution function (PDRF) 1403, the PDRF1403 is connected to the first RNMF1401 and the second RNMF1402, and the PDRF1403 is further connected to the first user plane network element 1404 and the second user plane network element 1405, and for the description of the specific function of the PDRF1403, refer to fig. 15, and the following specific implementation process of the method shown in fig. 15 is described:

step 1501, the UE transmits a measurement report to the first RNMF.

The first RNMF determines a target cell according to the received measurement report, where the target cell is a cell to which the UE needs to be handed over, and the first RNMF determines whether the target cell is within a service range of the first RNMF according to an identifier (target ID) of the target cell, where in this embodiment, the target cell is not within the service range of the first RNMF, and none of an AMF, an SMF, and a UDM, which are used for a core network control plane function for serving the UE before the handover and the UE after the handover, is changed into an example, for an exemplary description.

Step 1502, the first RNMF transmits a handover instruction to the first RRC.

In step 1503, the first RRC sends the handover request to the first RNMF.

For the specific execution process of step 1502 to step 1503 shown in this embodiment, please refer to step 1002 to step 1003 shown in fig. 10, which is not described in detail.

Step 1504, the first RNMF transmits a handover request to the second RNMF.

In this embodiment, the first RNMF may determine, according to the target ID, a second RNMF capable of serving the UE after the handover, and send the handover request to the determined second RNMF, where the handover request shown in this embodiment may carry a second DNN, second indication information, QoS profile, and packet filtering information corresponding to the QoS profile, and specific descriptions of parameters included in the handover request are shown in fig. 10, which is not specifically described in this embodiment.

Step 1505, the second RNMF sends a handover request to the second RRC.

The second RNMF determines a second RRC that can serve the UE after handover based on the target ID, and transmits the handover request to the determined second RRC.

In this embodiment, the second RNMF needs a destination address, where the destination address is an address of the PDRF, and for example, the address of the PDRF may be an IP address of the PDRF and/or a MAC address of the PDRF.

The second RNMF determines the destination address in two optional ways:

one, the handover request received by the second RNMF carries the destination address;

for example, the first RNMF may determine the destination address and carry the determined destination address in the handover request, and a specific procedure of the first RNMF determining the destination address may be:

the first RNMF may select a PDRF based on the configuration of the first RNMF, i.e., the first RNMF has been configured with a fixed PDRF, such as an IP address of a PDRF configured and/or a MAC address of the PDRF, and then the first RNMF may determine that the IP address of a PDRF and/or the MAC address of the PDRF stored by the first RNMF is the destination address based on the configuration; optionally, the first RNMF may further determine the PDRF through a dynamic query manner, for example, in a case that a Domain Name System (DNS) has been configured with an IP address of the PDRF and/or a MAC address of the PDRF, the first RNMF may obtain the destination address through the DNS query manner, and for example, the first RNMF queries the destination address stored by the DNS according to an ID of a data center where the first RNMF is located or according to a RAT served by the first RNMF, and/or a cell (cell), and/or a Public Land Mobile Network (PLMN), and the like.

Alternatively, the specific process of the second RNMF acquiring the destination address may refer to the specific process of the first RNMF acquiring the destination address, which is not described in detail herein.

In this embodiment, after the second RRC receives the handover request, the second RRC may establish an RRC context for the UE according to the handover request, and the second RRC allocates a Data Radio Bearer (DRB) Identifier (ID) for a data connection (PDU Session) of the UE, where the PDU Session is used to establish a service for exchanging PDU packets between the UE and the second DU, that is, is used to establish a data transmission channel between the UE and the second DU. And the second RRC selects a second PDCP-C capable of serving the UE after the handover based on the target ID.

Step 1506, the second RRC sends a PDU session resource setup message to the second PDCP-C.

Step 1507, the second PDCP-C sends a context setup request message to the second user plane network element.

For details of the specific execution process from step 1506 to step 1507 shown in this embodiment, please refer to step 1005 to step 1006 shown in fig. 10, which is not repeated herein.

Step 1508, the second user plane network element sends a context setup response message to the second PDCP-C.

The context establishment response message shown in this embodiment carries the address of the second user plane network element and the DRB id, and a detailed description of the DRB id is shown in fig. 10 and is not described in detail in this embodiment. The address of the second user plane network element may be an IP address of the second user plane network element and/or an MAC address of the second user plane network element.

Step 1509, the second PDCP-C sends a signaling message to the second DU.

Step 1510, the second PDCP-C sends a PDU session resource setup response to the second RRC.

Step 1511, the second RRC sends a handover request confirm message to the second RNMF.

And after receiving the PDU session resource setup response, the second RRC sends a handover Request acknowledgement (HO Request Ack) message to the second RNMF, wherein the HO Request Ack message carries the PDU session ID and the address of the second user plane network element.

Step 1512, the second RNMF sends a create route request message to the PDRF.

In the above step 1505, the second RNMF has determined the address of the PDRF, i.e. the destination address, and then the second RNMF may send the create route request message to the PDRF with the destination address, wherein the create route request (create route info) message includes the IP address of the UE and the address of the second user plane network element. And the IP address of the UE is allocated to the UE by the SMF and is sent to the second RNMF.

In this embodiment, an example is given that the second RNMF directly sends the request message for creating a route to the PDRF, and optionally, the second RNMF may also send the request message for creating a route to the first RNMF, and the first RNMF forwards the request message for creating a route to the PDRF.

In this embodiment, after the PDRF receives the route creation request message, the PDRF may create a mapping relationship between the IP address of the UE and a second forwarding path, and when the PDRF receives a downlink data packet, the PDRF may determine, based on a destination IP (that is, the IP address of the UE) in a header of the downlink data packet, the second forwarding path corresponding to the IP address of the UE, and forward the downlink data packet through the second forwarding path, for example, the second forwarding path shown in this embodiment is a forwarding path for transmitting the downlink data packet to an address of the second user plane network element, that is, the PDRF shown in this embodiment may forward the downlink data packet to the second user plane network element qualified by the second user plane network element.

Step 1513, the PDRF sends a create route request acknowledge message to the second RNMF.

When the PDRF completes creating the mapping relationship between the IP address of the UE and the second forwarding path, the PDRF sends a create routing request acknowledgement (create routing info ack) message to the second RNMF, where the create routing request acknowledgement message carries the IP address of the UE and the first indication parameter, and a specific value of the first indication parameter is not limited in this embodiment, as long as the first indication parameter can indicate that the PDRF completes creating the mapping relationship between the IP address of the UE and the second forwarding path, this embodiment takes the value of the first indication parameter as success for example.

Step 1514, the second RNMF sends a handover request confirm message to the first RNMF.

The handover Request acknowledgement (HO Request Ack) message carries parameter information such as the first indication information, the destination address, and the packet filtering information, where the first indication information is used to indicate the first user plane network element to create a mapping relationship between the destination address and the packet filtering information.

Step 1515, the first RNMF sends a handover request confirm message to the first RRC.

Step 1516, the first RRC sends a handover command to the first PDCP-C.

Step 1517, the first PDCP-C sends a context modification request message to the first user plane network element.

The specific execution process of steps 1515 to 1517 shown in this embodiment is shown in steps 1011 to 1013 shown in fig. 10, which is not described in detail.

Step 1518, the first user plane network element receives the context modification request message.

Wherein the first user plane network element may modify the mapping relationship between the packet filtering information according to the first indication information included in the context modification request message, for example, before the UE is handed over, the first user plane network element has created the mapping relationship between the packet filtering information and the DRB, when the first user plane network element receives the first indication information, the first user plane network element modifies the mapping relationship between the packet filtering information and the DRB into the mapping relationship between the packet filtering information and the destination address, and when the first user plane network element modifies the mapping relationship between the packet filtering information and the DRB into the mapping relationship between the packet filtering information and the destination address, if the first user plane network element receives a downlink data packet, the first user plane network element determines that IP quintuple information in the downlink data packet is the same as the packet filtering information, the first user plane network element may determine a first forwarding path corresponding to the packet filtering information, and forward a downlink data packet through the first forwarding path, for example, the first forwarding path shown in this embodiment is a forwarding path for transmitting a data packet to the destination address, that is, the first user plane network element shown in this embodiment may forward the downlink data packet to the PDRF having the destination address.

Step 1519, the first user plane network element sends a context modification response message to the first PDCP-C.

The context modification response message is used to indicate that the first user plane network element has successfully created the corresponding relationship between the packet filtering information and the first forwarding path.

Step 1520, the first PDCP-C sends a handover command to the UE.

Step 1521, the UE sends a handover complete acknowledgement message to the first RNMF.

The detailed execution process of step 1519 to step 1521 shown in this embodiment is please refer to the detailed execution process of step 1015 to step 1017 shown in fig. 10, which is not described in detail in this embodiment.

By using the method shown in this embodiment, in a process of switching the UE to a target cell, the first user plane network element may create a mapping relationship between packet filtering information and a destination address, and when the first user plane network element receives a downlink data packet matching the packet filtering information, the first user plane network element sends the downlink data packet to the PDRF, and the PDRF forwards the downlink data packet to the second user plane network element according to the created mapping relationship, so that the creation of a forwarding path between the first user plane network element and the PDRF, and between the PDRF and the second user plane network element is realized without changing an IP address of the UE, and the continuity of a UE service is ensured through the first forwarding path.

How to implement uplink data packet transmission and downlink data packet transmission after the UE is handed over to the target cell is described below with reference to fig. 16 based on the UE being handed over to the target cell as shown in fig. 15;

step 1601, the first user plane network element receives a downlink data packet.

Continuing with the example shown in fig. 14, the first user plane network element 1404 receives downstream packets from the first DN1406 via an N6 interface.

Step 1602, the first user plane network element determines a first forwarding path.

As can be seen from the embodiment shown in fig. 15, the first user plane network element stores a mapping relationship between packet filtering information and a destination address, when the first user plane network element receives the downlink data packet, the first user plane network element may obtain IP quintuple information in the downlink data packet and obtain packet filtering information that is the same as the IP quintuple information in the downlink data packet, and the first user plane network element may determine, according to the stored mapping relationship, a first forwarding path corresponding to the packet filtering information, that is, the first user plane network element determines to send the downlink data packet to the PDRF1403 having the destination address.

Step 1603, the first user plane network element sends the downlink data packet to the PDRF.

In this embodiment, the first forwarding path is a path for transmitting a data packet to the destination address, and the destination address is an address possessed by the PDRF, and thus, the first user plane network element may send the downstream data packet to the PDRF with the destination address.

Step 1604, the PDRF sends a downlink data packet to the second user plane network element.

As can be seen from the embodiment shown in fig. 15, in this embodiment, the PDRF already creates a second forwarding path, and then the PDRF may determine a corresponding second forwarding path according to the received downlink data packet, and send the downlink data packet to the second user plane network element through the second forwarding path.

Step 1605, the second user plane network element sends the downlink data packet to the UE.

In this embodiment, the second user plane network element has created a mapping relationship between packet filtering information and a target DRB, and when the second user plane network element receives a downlink data packet, the second user plane network element may obtain an IP quintuple included in the downlink data packet and obtain the packet filtering information corresponding to the IP quintuple information in the downlink data packet, and may obtain the target DRB corresponding to the packet filtering information, and the second user plane network element may send the data packet to the UE through the target DRB.

Step 1606, the UE sends the uplink data packet to the second DU.

In this embodiment, when the UE is connected to the target cell, as shown in fig. 14 as an example, when the UE1400 has an uplink data packet to send, the UE1400 may send the uplink data packet to the second DU 1410.

Step 1607, the second DU sends the uplink data packet to the second user plane network element.

Step 1608, the second user plane network element sends the uplink data packet to the second DN.

In this embodiment, with reference to fig. 14, when the second user plane network element 1405 receives the uplink data packet sent by the UE1400, the second user plane network element 1405 may send the uplink data packet to the second DN1411 through an N6 interface, so as to implement sending the uplink data packet.

By adopting the method shown in this embodiment, if the first user plane network element receives a downlink data packet, the first user plane network element can directly send the downlink data packet to the PDRF according to the created mapping relationship between the packet filtering information and the destination address, and then the PDRF forwards the downlink data packet to the second user plane network element, thereby effectively ensuring the continuity of the UE service and improving the efficiency of data transmission.

Continuing with the description of another embodiment of the method for performing handover shown in fig. 17 and fig. 18, in the embodiment shown in fig. 17 and fig. 18, a control plane network element performing handover is exemplarily illustrated as a first radio network management function RNMF, a specific description of the first RNMF is please refer to fig. 9, which is not described in detail in this embodiment, the communication system shown in this embodiment further includes a PDRF1700, the PDRF1700 is connected to the first RNMF1701, the PDRF1700 is further connected to a first user plane network element 1702 and a second user plane network element 1703, which are specific descriptions of other network elements of the communication system shown in this embodiment, which are detailed descriptions in the above embodiment, which are not described in this embodiment specifically, and the method shown in this embodiment specifically includes:

step 1801, the UE sends a measurement report to the first RNMF.

Step 1802, the first RNMF transmits a handover instruction to the first RRC.

Step 1803, the first RRC sends the handover request to the first RNMF.

Step 1804, the first RNMF sends a handover request to the second RRC.

Step 1805, the second RRC sends a PDU session resource setup message to the second PDCP-C.

Step 1806, the second PDCP-C sends a context setup request message to the second user plane network element.

For the specific execution process of step 1801 to step 1806 shown in this embodiment, please refer to step 1001 to step 1006 shown in fig. 10, which is not described in detail in this embodiment.

Step 1807, the second user plane network element sends a context setup response message to the second PDCP-C.

The context setup response (context setup response) message sent by the second user plane network element carries the DRB id and the address of the second user plane network element, for example, the address of the second user plane network element shown in this embodiment may be an IP address of the second user plane network element and/or an MAC address of the second user plane network element.

Step 1808, the second PDCP-C sends a signaling message to the second DU.

Step 1809, the second PDCP-C sends a PDU session resource setup response to the second RRC.

Step 1810, the second RRC sends a handover request confirm message to the first RNMF.

Step 1811, the first RNMF determines the destination address.

The destination address shown in this embodiment is an address of the PDRF, and the description of the specific process for determining the destination address by the first RNMF shown in this embodiment may refer to step 1505 shown in fig. 15, which is not specifically described in this embodiment.

Step 1812, the first RNMF sends a create route request message to the PDRF.

In this embodiment, if the first RNMF has determined that the PDRF has the address, that is, the destination address, the first RNMF may send the create route request message to the PDRF having the destination address, where the create route request (create route info) message includes an IP address of a UE and the destination address.

After receiving the message requesting to create the route, the PDRF may create a second forwarding path, and for a specific description of the second forwarding path, please refer to step 1512 shown in fig. 15 in detail, which is not described in detail specifically.

Step 1813, PDRF sends create route request acknowledge message to the first RNMF.

When the PDRF completes creating the mapping relationship between the IP address of the UE and the second forwarding path, the PDRF sends a create routing request acknowledgement (create routing info ack) message to the first RNMF, where the create routing request acknowledgement message carries the IP address of the UE and the first indication parameter, and a specific value of the first indication parameter is not limited in this embodiment, as long as the first indication parameter can indicate that the PDRF completes creating the mapping relationship between the IP address of the UE and the second forwarding path, this embodiment takes the value of the first indication parameter as success for example.

Step 1814, the first RNMF sends a handover request confirm message to the first RRC.

Step 1815, the first RRC sends a handover command to the first PDCP-C.

Step 1816, the first PDCP-C sends a context modification request message to the first user plane network element.

Step 1817, the first user plane network element receives the context modification request message.

Step 1818, the first user plane network element sends a context modification response message to the first PDCP-C.

Step 1819, the first PDCP-C sends a handover command to the UE.

Step 1820, the UE sends a handover complete acknowledgement message to the first RNMF.

For details of the specific execution process from step 1814 to step 1820 shown in this embodiment, please refer to step 1515 to step 1521 shown in fig. 15, which is not described in detail in this embodiment.

By using the method shown in this embodiment, in a process that the first RNMF switches the UE to a target cell, the first user plane network element may create a mapping relationship between packet filtering information and a destination address, and when the first user plane network element receives a downlink data packet matching the packet filtering information, the first user plane network element sends the downlink data packet to the PDRF, and the PDRF forwards the downlink data packet to the second user plane network element according to the created mapping relationship, so that the creation of a forwarding path between the first user plane network element and the PDRF, and between the PDRF and the second user plane network element is realized without changing an IP address of the UE, and the continuity of a UE service is ensured through the first forwarding path.

Based on the specific process of how to implement the transmission of the uplink data packet and the downlink data packet after the UE is switched to the target cell as shown in fig. 18, please refer to fig. 14, which is not described in detail.

In the following, with reference to fig. 19 and fig. 20, another embodiment of the method for performing handover processing in the present application is described, where in the embodiment shown in fig. 19 and fig. 20, a control plane network element performing handover is a second radio access network control plane functional network element RRC1901 as an example, and first, a structure of the communication system provided in fig. 19 is described: the communication system shown in this embodiment includes a packet routing dispatch function (PDRF) 1902, where the PDRF1902 is connected to a first RRC1903 and a second RRC1901, and the PDRF1902 is further connected to a first user plane network 1904 and a second user plane network 1905, for an explanation of a specific function of the PDRF1902, please refer to fig. 15, and the following describes, with reference to fig. 20, a specific implementation process of the method shown in this embodiment:

step 2001, the UE transmits a measurement report to the first RRC.

The specific process of the first RRC determining the target cell according to the received measurement report may refer to the process of the first RRC determining the target cell in step 1501 shown in fig. 15, which is not described in detail.

Step 2002, the first RCC sends a handover request to the second RRC.

In this embodiment, the first RRC may determine, according to the target ID, a second RRC that can serve the UE after the handover, and send the handover request to the determined second RRC, where the handover request shown in this embodiment may carry a second DNN, second indication information, QoS profile, and packet filtering information corresponding to the QoS profile, and specific descriptions of parameters included in the handover request are shown in fig. 10, and are not specifically described in this embodiment.

In this embodiment, the second RRC needs a destination address, where the destination address is an address of the PDRF, for example, the address of the PDRF may be an IP address of the PDRF and/or a MAC address of the PDRF. The manner of determining the destination address by the second RRC may refer to a specific process of determining the destination address by the second RNMF shown in fig. 15, which is not described in detail,

Step 2003, the second RRC sends a PDU session resource establishment message to the second PDCP-C.

Step 2004, the second PDCP-C sends a context setup request message to the second user plane network element.

Step 2005, the second user plane network element sends a context setup response message to the second PDCP-C.

The context establishment response message shown in this embodiment carries the address of the second user plane network element and the DRB id, and for a specific description of the DRB id, refer to fig. 15, which is not specifically described in this embodiment. The address of the second user plane network element may be an IP address of the second user plane network element and/or an MAC address of the second user plane network element.

Step 2006, the second PDCP-C sends a signaling message to the second DU.

Step 2007, the second PDCP-C sends a PDU session resource establishment response to the second RRC.

For details of the specific execution process from step 2003 to step 2007 shown in this embodiment, please refer to steps 1506 to 1510 shown in fig. 15, and the detailed execution process is not repeated.

Step 2008, the second RRC sends a create route request message to the PDRF.

In a case that the second RRC has determined the address that the PDRF has, that is, the destination address, the second RRC may send the route creation request message to the PDRF having the destination address, where details of the route creation request message are shown in step 1512 shown in fig. 15, and details are not repeated in this embodiment.

Step 2009, PDRF sends create route request acknowledge message to the second RRC.

The specific execution process of step 2009 in this embodiment is shown in step 1513 in fig. 15 for details, which are not described in detail herein.

Step 2010, the second RRC sends a switching request confirmation message to the first RRC.

Step 2011, the first RRC sends a handover command to the first PDCP-C.

In case that the first RRC receives the handover command sent by the second RCC, the first RRC may send the handover command to the first PDCP-C.

Step 2012, the first PDCP-C sends a context modification request message to the first user plane network element.

Step 2013, the first user plane network element receives the context modification request message.

Step 2014, the first user plane network element sends a context modification response message to the first PDCP-C.

Step 2015, the first PDCP-C sends a handover command to the UE.

For the specific execution process of step 2012 to step 2015 shown in this embodiment, please refer to the specific execution process of step 1517 to step 1520 shown in fig. 15 in detail, which is not described in detail in this embodiment.

Step 2016, the UE sends a handover complete confirm message to the first RRC.

By using the method shown in this embodiment, in the process of switching the UE to the target cell by the second RRC, the first user plane network element may create a mapping relationship between packet filtering information and a destination address, and when the first user plane network element receives a downlink data packet matching the packet filtering information, the first user plane network element sends the downlink data packet to the PDRF, and the PDRF forwards the downlink data packet to the second user plane network element according to the created mapping relationship, so that the IP address of the UE is not changed, the creation of a forwarding path between the first user plane network element and the PDRF, and between the PDRF and the second user plane network element is realized, and the continuity of the UE service is guaranteed through the first forwarding path.

Based on the specific process of how to implement the transmission of the uplink data packet and the downlink data packet after the UE is switched to the target cell as shown in fig. 20, please refer to fig. 14, which is not described in detail.

In the following, with reference to fig. 21 and fig. 22, another embodiment of the method for performing a handover process shown in this application is described, in the embodiment shown in fig. 21 and fig. 22, a control plane network element performing a handover is exemplarily described as the second RNMF2101, and first, a structure of the communication system provided in fig. 21 is described: the communication system shown in this embodiment includes a packet distribution function logic network element PDRF2102, where the PDRF2102 is connected to the first RNMF2103 and the second RNMF2101, and the PDRF2102 is further connected to the first user plane network element 2104 and the second user plane network element 2105, for example, the communication system shown in this embodiment exemplarily changes an RNMF, an SMF, an AMF, and a UDM that serve before and after UE handover into an example, as shown in fig. 21, takes the first RNMF2103, the first AMF2110, the first SMF2111, and the first UDM2112 that serve the UE2106 before handover into an example, and takes the second RNMF2101, the second AMF2113, the second SMF2114, and the second UDM2115 that serve the UE2106 after handover into an example. The following describes a specific implementation procedure of the method shown in this embodiment with reference to fig. 22:

step 2201, the UE sends a measurement report to the first RNMF.

As shown in conjunction with the structure of the communication system shown in fig. 21, the UE2106 reports the measurement report to the first RNMF2103 sequentially through the first DU2107, the first PDCP-C2108, and the first RRC2109, where the first PDCP-C2103 and the first RRC2104 are both connected to the first RNMF2103, and for a specific description of the first RNMF, reference may be made to the description shown in fig. 5, which is not repeated.

Step 2202, the first RNMF transmits a handover instruction to the first RRC.

In this embodiment, an example is given by taking the target cell not within the service range of the first RNMF as an example, and if the target cell is not within the service range of the first RNMF, the second RNMF, the AMF, the SMF, and the like for serving the UE after handover all need to be changed.

Step 2203, the first RRC sends the handover request to the first RNMF.

For details of the specific execution process of step 2203 shown in this embodiment, please refer to step 1503 shown in fig. 15, and the specific execution process is not described in detail in this embodiment.

Step 2204, the second RNMF obtains the handover request.

The following describes a specific procedure of acquiring the handover request by the second RNMF in conjunction with specific steps:

step a1, the first RNMF sends a handover request to the first AMF.

The first RNMF determines, according to the received target ID, the first AMF for serving the UE before handover, and sends the handover request to the first AMF, where the handover request carries a second DNN, second indication information (selection indication), a quality of service profile (QoS profile), and Packet filter (Packet filter) information corresponding to the QoS profile, and a specific description of the handover request is shown in step 1004 shown in fig. 10, and is not specifically described in this embodiment.

Optionally, the handover request may further include a destination address determined by the first RNMF, where the destination address is an address of the PDRF, and a specific process of determining the destination address for the first RNMF is shown in step 1505 shown in fig. 15, which is not described in detail in this embodiment.

Step a2, the first AMF sends a create UE context request message to the second AMF.

And under the condition that the first AMF receives the handover request, the first AMF determines a second AMF based on the target ID, where the second AMF is an AMF used for serving the UE after handover, the first AMF may send a create UE context request (create UE context request) message to the second AMF, the create UE context request carries parameters such as the second DNN, second indication information (selection indication), the quality of service profile (QoS profile), and Packet filtering (Packet filter) information corresponding to the QoS profile, and the create UE context request may also carry the destination address.

The request message for creating a UE context shown in this embodiment further includes a second indication parameter, where the second indication parameter is used to indicate that a second SMF omits performing User Plane Function (UPF) selection, and the second indication parameter is further used to indicate that the second SMF omits performing N4 interface session establishment between the second SMF and the UPF.

The specific value of the second indication parameter is not limited in this embodiment, as long as the second SMF omits performing UPF selection and performing N4 interface session establishment through the second indication parameter, and this embodiment takes the value of the second indication parameter as SMF selection off and N4session off for exemplary explanation.

Step a3, the second AMF sends a create context request message to the second SMF.

In this embodiment, the second AMF performs creation of a UE context and determines a second SMF capable of serving the UE after handover, where the second AMF may send a create context request (create context request) message to the second SMF, where the create context request includes all parameters included in the context request message.

Step a4, the second SMF sends a create context response message to the second ATM.

In this embodiment, after the second SMF receives the create context request message, the second SMF may omit performing UPF selection and omitting performing N4 interface session establishment according to the second indication parameter included in the create context request message. The second SMF creates the context of the UE only locally and sends a create context response message to the second ATM.

Step a5, the second ATM sends a handover request to the second RNMF.

The second ATM selects a second RNMF capable of serving the UE after the handover according to the target ID, and the second ATM sends the handover request to the determined second RNMF, where the handover request shown in this embodiment may carry a second DNN, second indication information, QoS profile, packet filtering information corresponding to the QoS profile, and the destination address, and a specific description of each parameter included in the handover request is described in the foregoing, and is not described in detail.

Step a6, the second RNMF receiving the handover request.

Step 2205, the second RNMF sends a handover request to the second RRC.

For a specific execution process of step 2209 shown in this embodiment, please refer to step 1505 in detail, which is not described in detail;

optionally, if the handover request does not include the destination address, the second RNMF may determine the destination address, and a specific process of determining the destination address by the second RNMF may be referred to in step 1505, which is not described in detail.

Step 2206, the second RRC sends a PDU session resource establishment message to the second PDCP-C.

Step 2207, the second PDCP-C sends a context setup request message to the second user plane network element.

Step 2208, the second user plane network element sends a context setup response message to the second PDCP-C.

Step 2209, the second PDCP-C sends a signaling message to the second DU.

Step 2210, the second PDCP-C sends a PDU session resource setup response to the second RRC.

Step 2211, the second RRC sends a handover request confirm message to the second RNMF.

Step 2212, the second RNMF sends a create route request message to the PDRF.

Step 2213, PDRF sends create route request acknowledge message to second RNMF.

For the specific execution process of step 2206 to step 2213 shown in this embodiment, please refer to step 1506 to step 1513 shown in fig. 15 in detail, and the specific execution process is not repeated.

Step 2214, the first RNMF obtains the handover request confirm message.

The following describes a specific procedure of acquiring the handover request acknowledgement message by the first RNMF:

and step B1, the second RNMF sending a switching request confirmation message to the second AMF.

Step B2, the second AMF sends a create UE context response message to the first AMF.

In this embodiment, a create UE context response (create UE context response) message sent by the second AMF to the first AMF carries parameters such as the first indication information, the destination address, and the packet filtering information.

In step B3, the first AMF transmits a handover request confirm message to the first RNMF.

The handover request acknowledgement message shown in this embodiment carries parameters such as the first indication information, the destination address, and the packet filtering information.

Step B4, the first RNMF receiving the handover request acknowledge message sent by the first AMF.

Step 2215, the first RNMF sends a handover request confirm message to the first RRC.

Step 2216, the first RRC sends a handover command to the first PDCP-C.

Step 2217, the first PDCP-C sends a context modification request message to the first user plane network element.

Step 2218, the first user plane network element receives the context modification request message.

Step 2219, the first user plane network element sends a context modification response message to the first PDCP-C.

Step 2220, the first PDCP-C sends a handover command to the UE.

Step 2221, the UE sends a handover complete acknowledgement message to the first RNMF.

For details of the specific execution process from step 2215 to step 2221 shown in this embodiment, please refer to step 1515 to step 1521 shown in fig. 15, and the specific execution process is not described in detail in this embodiment.

By using the method shown in this embodiment, in a process of switching the UE to a target cell, the first user plane network element may create a mapping relationship between packet filtering information and a destination address, and when the first user plane network element receives a downlink data packet matching the packet filtering information, the first user plane network element sends the downlink data packet to the PDRF, and then the PDRF forwards the downlink data packet to the second user plane network element according to the created mapping relationship, so that it is ensured that an IP address of the UE is not changed and a forwarding path between the first user plane network element and the PDRF and between the PDRF and the second user plane network element is created when a network element on a core network side serving the UE is changed, and continuity of a UE service is ensured through the first forwarding path.

Based on the method shown in fig. 22, how to implement a specific process of transmitting an uplink data packet and a downlink data packet after the UE switches to the target cell is shown in fig. 16 and will not be described in detail.

Another embodiment of the handover processing method shown in the present application is described based on the structure of the communication system shown in fig. 14, and how to perform a PDU session release procedure after the UE completely migrates to the target cell is described below with reference to fig. 23:

step 2301, the second user plane network element sends the event identification information to the second RNMF.

In this embodiment, the second user plane network element may be preconfigured with a timer, and the second user plane network element monitors, based on the timer, a duration that no service data transmission is performed on the data radio bearers corresponding to each packet of filtering information, and if the second user plane network element determines that there is a data radio bearer on which data is transmitted before the timer expires, stops timing by the timer of the data radio bearer. And if the second user plane network element acquires the data radio bearer which is not subjected to data transmission when the timer is overtime, generating event identification information aiming at the data radio bearer, wherein the event identification information is used for identifying an event that the duration of no data transmission on the data radio bearer corresponding to the packet filtering information is greater than or equal to the preset duration.

The event identification information shown in this embodiment further includes an identifier (DRB id) of a data radio bearer that has not yet performed data transmission when the timer is overtime, that is, the event identification information may also be used to identify an event that a duration of no data transmission on the data radio bearer corresponding to the DRB id is greater than or equal to a preset duration.

The second user plane network element sends the generated event identification information to the second RNMF, as shown in fig. 12, a specific process of sending the event identification information to the second RNMF by the second user plane network element may be that the second user plane network element sends the event identification information to the second RNMF sequentially through the second PDCP-C and the second RRC.

Step 2302, the second RNMF sends a context release message to the SMF.

In this embodiment, when the second RNMF receives the event identification information, the second RNMF may determine a PDU Session ID, where the PDU Session ID is used to identify a PDU Session that needs to be released. And the second RNMF sends an event report (event report) message to the SMF, wherein the event report carries the PDU Session ID and parameters included in the event identification information, and the context release message is used for indicating the SMF to delete the context of the interface between the SMF and the second RRC.

Step 2303, the SMF sends a session release request message to the second RNMF.

And under the condition that the SMF receives the context release message, the SMF performs a PDU session release process, namely the SMF deletes the context of the interface between the SMF and the second RRC according to the context release message. After the SMF successfully deletes the context of the interface between the SMF and the second RRC, the SMF sends a session release request message to the second RNMF, the session release request message is sent to carry the PDU session ID and a cause value (cause with re-attempt request), and the cause with re-attempt request is used for indicating the UE to re-initiate the establishment of the PDU session after the PDU session is released.

Step 2304, the second RNMF sends the session release request message to the second DU.

Referring to fig. 12, the second RNMF shown in this embodiment may sequentially transmit the session release request message to the second DU through the second RRC and the second PDCP-C.

Step 2305, the second DU sends the resource release message to the UE.

In this embodiment, after the second DU receives the session release request message, the second DU may send a resource release message (resource release) message carrying a PDU session release accept/PDU session release accept and a cause with a re-invalid request to the UE, where the PDU session release accept is used to indicate that the second DU agrees to perform a release message of the PDU session resource.

Step 2306, the UE sends a PDU session release complete message to the second RNMF.

In this embodiment, after the UE receives the resource release message, the UE may release the resource related to the PDU session. After the UE successfully releases the resources related to the PDU session, the UE sends a release message of the PDU session resources to the second RNMF, for example, the UE may send the session release completion message to the second RNMF sequentially through the second DU, the second PDCP-C, and the second RRC.

Step 2307, the second RNMF sends a PDU session release instruction to the first RNMF.

After the second RNMF receives the PDU session release completion message, the second RNMF determines that the PDU session resource release of the UE on the side of the target cell is completed, if the second RNMF is used for continuously releasing the PDU session resource of the source cell where the UE resides before switching, the second RNMF sends a PDU session release instruction to the first RNMF.

In this embodiment, after the first RNMF receives the PDU session release instruction, the first RNMF initiates release of the first RRC, the first PDPC-C, and the PDU session resource on the first user plane network element.

Step 2308, the second RNMF sends the delete route information to the PDRF.

As shown in the foregoing embodiment, if the PDRF has created a mapping relationship between the IP address of the UE and the second forwarding path, the PDRF deletes the mapping relationship identified by the IP address of the UE when the PDRF receives the IP address of the UE carried by the deleted routing information, where the mapping relationship identified by the IP address of the UE is a mapping relationship between the IP address of the UE and the address of the second user plane network element.

Step 2309, the second RNMF sends a PDU session release response message to the SMF.

In this embodiment, after the second RNMF determines that the PDU session resource of the target cell, the PDU session resource of the source cell, and the mapping relationship stored in the PDRF are all successfully released, the second RNMF replies a PDU session release response (PDU session release) message to the SMF, where the PDU session release response carries the PDU session ID and the third indication parameter, and a value different from the third indication parameter may indicate whether the PDU session resource of the target cell, the PDU session resource of the source cell, and the mapping relationship stored in the PDRF are all successfully released, for example, if the value of the third indication parameter is "success", the third indication parameter is used to indicate whether the PDU session resource of the target cell, the PDU session resource of the source cell, and the mapping relationship stored in the PDRF are all successfully released, for another example, if the value of the third indication parameter is "failure", the third indication parameter is used to indicate that release of at least one of the PDU session resource of the target cell, the PDU session resource of the source cell, and the mapping relationship stored in the PDRF fails.

By adopting the method shown in this embodiment, after the UE service is completed, the second user plane network element reports the event identifier information to the second RNMF, the second RNMF may request the SMF to initiate a PDU session release procedure, and the SMF may further instruct the UE to reinitiate the PDU session establishment after the PDU session is released through a cause with a re-established request. In a PDU session release flow initiated by the SMF, the second RNMF may simultaneously delete a mapping relationship on the PDRF and context information related to the PDU session on the first user plane network element.

A specific structure of the user plane network element provided in this embodiment is exemplarily described below with reference to fig. 24, where the user plane network element shown in fig. 24 is the first user plane network element shown in the foregoing embodiment, and a specific process of the method for performing a handover process by the first user plane network element is shown in the foregoing embodiment and is not specifically described again;

as shown in fig. 24, the user plane network element includes:

an obtaining unit 2401, configured to obtain a first mapping relationship, where the first mapping relationship includes a correspondence between packet filtering information and an identifier of a data radio bearer, the packet filtering information includes an IP quintuple, and the data radio bearer is used for carrying a data packet;

a receiving unit 2402, configured to receive an address of a second user plane network element and the packet filtering information;

a processing unit 2403, configured to send the data packet to the address of the second user plane network element according to the packet filtering information.

Optionally, the receiving unit 2402 is further configured to receive the data packet;

the obtaining unit 2401 is further configured to obtain the packet filtering information included in the data packet.

Optionally, the receiving unit 2402 is further configured to receive indication information from a control plane network element, where the indication information is used to indicate the first user plane network element to send the data packet to an address of the second user plane network element according to the packet filtering information.

For a description of the beneficial effect of the method for performing a handover process by a user plane gateway element in this embodiment, please refer to the foregoing embodiment, which is not described in detail in this embodiment.

A specific structure of the user plane network element provided in this embodiment is exemplarily described below with reference to fig. 25, it should be clear that the user plane network element shown in this embodiment is the second user plane network element shown in the foregoing embodiment, and a specific process of the method for performing handover processing by the second user plane network element is shown in the foregoing embodiment and is not specifically described again;

as shown in fig. 25, the second user plane network element includes:

an obtaining unit 2501, configured to obtain a second mapping relationship, where the second mapping relationship includes a corresponding relationship between the packet filtering information and a data radio bearer, the packet filtering information includes an IP quintuple, and the data radio bearer is used for carrying a data packet;

a sending unit 2502, configured to send the address of the second user plane network element to a control plane network element, where the address of the second user plane network element is used for the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

Optionally, the user plane network element further includes a receiving unit 2503, configured to receive the data packet from the first user plane network element;

the obtaining unit 2501 is further configured to obtain the packet filtering information included in the data packet;

the user plane network element further includes a determining unit 2504, configured to determine to send the data packet through the data radio bearer according to the packet filtering information and the second mapping relationship.

A specific structure of the control plane network element provided in this embodiment is exemplarily described below with reference to fig. 26, and a specific process of the method for performing a handover process by the control plane network element shown in this embodiment is shown in the foregoing embodiment and is not described in detail specifically;

as shown in fig. 26, the control plane network element includes:

a sending unit 2601, configured to send packet filtering information and an identifier of a data radio bearer to a second user plane network element, where the packet filtering information includes an IP quintuple, and the data radio bearer is used to carry a data packet;

a receiving unit 2602, configured to receive an address of the second user plane network element from the second user plane network element;

the sending unit 2601 is further configured to send the address of the second user plane network element and the packet filtering information to the first user plane network element, where the address of the second user plane network element is used for the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

Optionally, the sending unit 2601 is further configured to send first indication information to the first user plane network element, where the indication information is used to indicate the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

For a description of the beneficial effect of the control plane network element performing the handover processing in this embodiment, please refer to the foregoing embodiment, which is not described in detail in this embodiment.

The following describes a specific structure of the data switching device provided in the present application with reference to fig. 27, where the data switching device shown in this embodiment is used to execute the data transmission method shown in any one of the above embodiments, and the detailed description of the data transmission method is shown in any one of the above embodiments, and the data switching device shown in this embodiment includes:

as shown in fig. 27, in order to implement the hardware structure of the data switching device 2700 in the data transmission method of the present invention: the data switching device 2700 includes at least one processor 2701, a communication bus 2702, a memory 2703, and at least one communication interface 2704.

The processor 2701 may be a general processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more ics for controlling the execution of programs in accordance with the present invention.

Communication bus 2702 may include a path that conveys information between the aforementioned components.

Communication interface 2704, which may be implemented using any transceiver or the like, is used for communicating with other devices or communication networks.

The memory 2703 may be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited to these. The memory may be self-contained and coupled to the processor via a bus. The memory may also be integral to the processor.

The memory 2703 is used for storing application codes for executing the present application, and the processor 2701 controls the execution. Processor 2701 is configured to execute application program code stored in memory 2703 in order to implement the logical functions of data switching apparatus 2700. In particular implementations, processor 2701 may include one or more CPUs, such as CPU0 and CPU1 in fig. 27, as one embodiment.

In one implementation, data switch 2700 may include multiple processors, such as processor 2701 and processor 2708 of fig. 27, for example, as an example. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In a specific implementation, the data switching apparatus 2700 may further include an output device 2705 and an input device 2706, as an embodiment. The output device 2705 is in communication with the processor 2701 and may display information in a variety of ways. The data switching apparatus 2700 may be a general-purpose computer device or a special-purpose computer device.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A method of handover processing, the method comprising:

the first user plane network element receives an address of a second user plane network element and the packet filtering information, wherein the address of the second user plane network element and the packet filtering information can be forwarded to an SDAP layer and a PDCP-U layer of the first user plane network element in a one-hop manner;

2. The method of claim 1, wherein before the first user plane network element sends the data packet to the address of the second user plane network element according to the packet filtering information, the method further comprises:

the first user plane network element receives the data packet;

and the first user plane network element acquires the packet filtering information included in the data packet.

3. The method according to claim 1 or 2, wherein before the first user plane network element sends the data packet to the address of the second user plane network element according to the packet filtering information, the method further comprises:

and the first user plane network element receives indication information from a control plane network element, wherein the indication information is used for indicating the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

4. A method of handover processing, the method comprising:

a second user plane network element acquires a second mapping relation, wherein the second mapping relation comprises a corresponding relation between packet filtering information and a data radio bearer, the packet filtering information comprises an IP five-tuple, and the data radio bearer is used for bearing a data packet;

5. The method of claim 4, further comprising:

the second user plane network element receives the data packet from the first user plane network element;

the second user plane network element acquires the packet filtering information included in the data packet;

6. A method of handover processing, the method comprising:

the control plane network element receives an address of the second user plane network element from the second user plane network element;

and the control plane network element sends the address of the second user plane network element and the packet filtering information to the first user plane network element, wherein the address of the second user plane network element is used for the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

7. The method of claim 6, further comprising:

and the control plane network element sends indication information to the first user plane network element, wherein the indication information is used for indicating the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

8. A user plane network element, comprising:

a receiving unit, configured to receive an address of a second user plane network element and the packet filtering information, where the address of the second user plane network element and the packet filtering information can be forwarded to an SDAP layer and a PDCP-U layer of the first user plane network element in one hop;

9. The user plane network element of claim 8,

the receiving unit is further configured to receive the data packet;

the obtaining unit is further configured to obtain the packet filtering information included in the data packet.

10. The user plane network element of claim 8 or 9,

the receiving unit is further configured to receive indication information from a control plane network element, where the indication information is used to indicate the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

11. A user plane network element, comprising:

an obtaining unit, configured to obtain a second mapping relationship, where the second mapping relationship includes a correspondence between packet filtering information and a data radio bearer, the packet filtering information includes an IP quintuple, and the data radio bearer is used for carrying a data packet;

a sending unit, configured to send an address of a second user plane network element to a control plane network element, where the address of the second user plane network element is used for the first user plane network element to send the data packet to the second user plane network element according to the packet filtering information.

12. The user plane network element of claim 11, wherein the user plane network element further comprises:

a receiving unit, configured to receive the data packet from the first user plane network element;

the obtaining unit is further configured to obtain the packet filtering information included in the data packet;

a determining unit, configured to determine to send the data packet through the data radio bearer according to the packet filtering information and the second mapping relationship.

13. A control plane network element, comprising:

14. The control plane network element of claim 13, wherein the sending unit is further configured to send indication information to the first user plane network element, where the indication information is used to instruct the first user plane network element to send the data packet to the address of the second user plane network element according to the packet filtering information.

15. A data switching apparatus comprising a processor and a memory, wherein,

a computer readable program stored in the memory;

the processor is configured to execute the method of any one of claims 1 to 7 by executing a program in the memory.

16. A computer-readable storage medium having stored thereon instructions for performing the method of any of claims 1 to 7.