CN109151929B

CN109151929B - Switching processing method, device and system of network system and storage medium

Info

Publication number: CN109151929B
Application number: CN201710466076.7A
Authority: CN
Inventors: 李振东; 朱进国; 卢飞
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2017-06-19
Filing date: 2017-06-19
Publication date: 2021-09-03
Anticipated expiration: 2037-06-19
Also published as: CN109151929A; WO2018233445A1

Abstract

The invention provides a switching processing method, a device and a system of a network system and a storage medium, wherein the method comprises the following steps: the AMF entity receives a forwarding reset request from a 4G network system to a 5G network system, selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the forwarding reset request comprises: 4G session information, the PDU session request including: the 4G session information and the PDU session request are used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF, and by adopting the technical scheme, the problems that the switching of the terminal from the 4G network system to the 5G network system fails and the like caused by large delay in the related technology are solved.

Description

Switching processing method, device and system of network system and storage medium

Technical Field

The present invention relates to the field of communications, and in particular, to a method, an apparatus, a system, and a storage medium for handover processing in a network system.

Background

The third Generation Partnership Project (3rd Generation Partnership Project, abbreviated to 3GPP) has evolved from R8 to a fourth Generation Long Term Evolution (LTE) mobile communication system. The network architecture is shown in fig. 1, and the functions of each network element in the architecture are as follows:

a terminal (User Equipment, abbreviated as UE) mainly accesses to a 4G network through a wireless air interface and obtains services, and the terminal exchanges information with a base station through the air interface and exchanges information with a mobility management entity of a core network through a non-Access Stratum signaling NAS (non-Access Stratum).

A base station (RAN, Radio Access Network, eNB) is responsible for scheduling air interface resources of a terminal Access Network and managing connection of an air interface.

A mobile management entity: the core Network control plane entity is mainly responsible for authentication, authorization and subscription check of users, user mobility management, Packet Data Network (PDN) connection and bearer maintenance, and functions of triggering paging in an IDLE state of a user.

Serving gateway Serving GW: the core network user plane functional entity is mainly responsible for interaction with the PDN GW under the roaming condition.

Packet data gateway PDN GW: the core network user plane functional entity is an access point of a terminal accessing a PDN network, is responsible for allocating user IP addresses and establishing, modifying and deleting network-triggered bearers, also has the functions of QoS control charging and the like, and is an anchor point of a user in a 3GPP system, thereby ensuring the IP addresses to be unchanged and ensuring the service continuity. In the control and forwarding separation architecture, the P-GW is further divided into 2 parts, one is a control entity PGW-C and the other is a user plane entity PGW-U. The PGW-C is responsible for signaling control, and the PGW-U is responsible for IP forwarding.

Home Subscription Server (HSS): subscription information of the user is stored.

And a Policy and charging control function (PCRF) responsible for making Policy decisions and charging rules. The PCRF provides traffic data flow-based network Control rules including detection of traffic data flow, Gating (Gating Control), Quality of Service (QoS) Control, and data flow-based charging rules, among others. And the PCRF sends the policy and charging rule formulated by the PCRF to the P-GW for execution.

The 3GPP starts to research a next generation Communication System (NextGen System) from R14, where the next generation Communication System can support three service types, namely Evolved Mobile Broadband (eMBB), massively connected Machine Communication (mtc), and Ultra Reliable Machine Communication (mtc), and the three service types have different network characteristics. Fig. 2 is a schematic diagram of a next generation mobile communication network architecture, in which the functions of each network element are as follows:

the UE is accessed to the network and obtains service mainly through the next generation wireless air interface, and the terminal exchanges information with the base station through the air interface and exchanges information with the public control plane function and the conversation control plane function of the core network through the non-access layer signaling.

The next generation base station (NG RAN, Radio Access Network, gNB) is responsible for scheduling air interface resources of the terminal Access Network and managing air interface connections.

Session Management Function (SMF): interacting with a terminal, mainly responsible for processing User (Packet Data Unit, abbreviated as PDU) session establishment, modification and deletion requests, and selecting User Plane Function (UPF); establishing user interface connection between the UE and the UPF; and a Policy Control Function (PCF) together with the session Quality of Service (QoS) parameters.

Access and Mobility Control Function (AMCF): is a common control plane function within the core network. One user only has one AMCF, which is responsible for authentication, authorization and subscription check of the user to ensure that the user is a legal user; user mobility management, including location registration and temporary identity allocation; when a user initiates a Packet Data Unit (PDU) connection establishment request, selecting a proper SMF; forwarding Non-Access Stratum (NAS) signaling between the UE and the SMF; and forwarding Access Stratum (AS) signaling between the base station and the SMF.

UPF: and providing user plane processing functions including data forwarding and QoS execution. The UPF also provides a user plane anchor point when the user moves, and service continuity is guaranteed.

PCF: the provided function is very similar to the PCRF in the 4G era.

Unified Data Management function (UDM for short): subscription data of the subscriber is stored, which is very similar to the HSS of the 4G era.

The deployment of the NextGen System (5G) is started to be deployed locally in a hotspot area, such as a city center, a business center and the like, when the UE accesses the 5G System, the coverage of the 5G System is removed along with the movement of the user, how to seamlessly switch to the 4G System must be solved, otherwise, the session is interrupted.

FIG. 3 is a network architecture for satisfying 4G < - - >5G bidirectional handover. The core characteristic of the method is that the architecture is compatible with 4G and 5G architectures. The core characteristics are that PGW-C and SMF are integrated, PGW-U and UPF are integrated, PCF and PCRF are integrated, and the user plane of UE is anchored on UPF/PGW-U all the time. An Nx interface is added between an Authentication Management Function (AMF) and an MME, and a cross-system handover request is sent on the interface. Therefore, when the UE is switched between the LTE and the 5G, seamless switching can be ensured.

When the UE and the network use bearer (bearer concept) in the 4G system, each bearer represents a corresponding Service flow (Service flows) and its QoS parameters. In a 5G system, the concept of QoS flow is adopted, and each QoS flow includes a corresponding QoS profile and a packet filter (packet filter).

Fig. 4 is a flowchart of switching from 4G to 5G in the prior art, which mainly includes the following steps:

step 400, the terminal UE already establishes a PDN connection in the 4G system, and may also establish a dedicated bearer;

step 401, a source 4G RAN node (eNB) finds that it needs to switch to 5G, and sends a handover request to MME, where the handover request carries target cell information;

step 402, the MME selects a target AMF according to the switching Request, and sends a Forward location Request to the AMF, wherein the Forward location Request carries PGW-C/SMF and S-GW addresses;

step 403, the AMF initiates a PDU Session Handover Request to the SMF/PGW-C address according to the SMF/PGW-C address, and the Request is sent to the vSMF first in a roaming scenario or a deployment reason;

step 404, the vSMF forwards a PDU Session Handover Request to the SMF/PGW-C;

step 405: if PCC is deployed, SMF CAN initiate PDU-CAN Session Modification to PCF/PCRF to obtain 5GS PCC rule of PDU Session after switching to 5G. At this time, the PCF/PCRF does not directly apply the 5GS PCC rule to the PDU session.

Step 406: the TSMF/PGW-C initiates N4session modification to the UPF/PGW-U to obtain uplink tunnel information;

step 407: the SMF/PGW-C sends PDU Session Handover Response to the AMF, wherein the PDU carries the authorized 5G Qos rule, EPS bearer Setup List, and uplink tunnel information of UPF/PGW-U, and when vSMF exists in step 403, the message is sent to the vSMF first.

Step 408: the vSMF selects a vUPF and initiates the N4Session Establishment procedure. And the vSMF provides the uplink tunnel information of the UPF/PGW-U for the vUPF, and the vUPF generates v-CN tunnel information (N3 uplink tunnel and N9 downlink tunnel) and sends the v-CN tunnel information to the vSMF. And the vSMF forwards PDU Session Handover Response to the AMF, wherein the PDU Session Handover Response carries the uplink tunnel information of authorized 5G Qos rule, EPS bearer Setup List and vUPF.

Step 409: and the AMF sends a Handover Request to the 5G RAN node, wherein the Handover Request at least comprises a PDU session ID, a corresponding QoS Profile and uplink tunnel information.

Step 410: the 5G RAN node sends a Handover Request acknowledgement to the AMF, wherein the Handover Request acknowledgement comprises N3 downlink tunnel information;

step 411: and the AMF sends a Modify PDU Session Request to the SMF/PGW-C, wherein the Modify PDU Session Request contains the downlink N3 tunnel information. When there is vSMF, the message is sent to the vSMF first, and the vSMF replaces the N3 downlink tunnel information with the N9 downlink tunnel information allocated in step 408, and sends the information to the SMF/PGW-C.

Step 412: SMF/PGW-C sends Modify PDU Response to AMF. When a vMSF exists, the message is sent to the vSMF first, and the vSMF is sent to the AMF again.

Step 413: the SMF/PGW-C requests a UPF/PGW-U to establish a temporary forwarding tunnel;

step 414: the AMF sends a Forward Relocation Response to the MME, wherein the Forward Relocation Response comprises information such as Serving GW change indication, EPS Bearer Setup List, TEIDs and the like;

step 415: MME sends a Create index Data Forwarding Tunnel Request to S-GW to Request the establishment of a temporary Forwarding Tunnel.

Steps 401 to 415 are a handover preparation phase, and the following steps are a handover execution phase.

Step 416: MME sends Handover Command to 4G RAN node, wherein temporary forwarding tunnel and bearing information are included

Step 417: the 4G RAN (eNB) sends a Handover Command to the UE, wherein the Handover Command comprises wireless information of a target 5G RAN;

step 418: and the UE accesses the target 5G RAN node according to the received 5G RAN wireless information and sends a Handover Confirm to the 5G RAN node.

At the moment, after the downlink data reaches the 4G RAN node, the downlink data passes through the S-GW, the PGW-U/UPF, the vUPF and the 5G RAN node through the forwarding tunnel and reaches the UE;

step 419: 5G RAN node sends Handover Notify to AMF

Step 420: and the AMF sends a Forward Relocation Complete Notification message to the MME to confirm that the handover is completed.

Step 421: AMF sends Handover Complete message to SMF/PGW-C. When a vSMF exists, the message is sent to the vSMF first. .

Step 422: the SMF/PGW-C updates the UPF/PGW-U with the tunnel information of the vUPF, and the UPF/PGW-U sends the downlink data to a target side (vUPF).

Step 423: SMF/PGW-C sends Handover Complete Ack to AMF.

The subsequent steps also include that the UE initiates a registration process in the 5G network, and the MME releases 4G network resources.

The above-described procedure is a procedure for switching one PDN connection to a 5G PDU session. When there are multiple PDN connections, the flows are similar, with the main differences:

step 403, a PDU session driver request needs to be sent to the SMF/PGW-C of each PDN connection;

step 408, initiating step 409 after all responses need to be received;

step 411, a Modify PDU session request needs to be sent to SMF/PGW-C of each PDN connection;

step 412, after all responses need to be received, sending a step 414 message to the MME;

in step 421, a Handover Complete needs to be sent to each SMF/PGW-C.

In the above procedure, the AMF receives a handover request from the MME of the 4G system, and the AMF is a network element unrelated to the session management function, and needs to query the SMF/PGW-C for session information in the 5G system, and reserve resources to the 5G RAN node after receiving all responses.

However, the above handover procedure has a great problem. When the AMF is in the visited network and the SMF/PGW-C is in the Home network in some specific scenarios (e.g. Home routed scenario), there is a large delay. This easily leads to handover failure. In addition, because a lot of signaling is used, a media path of the 5G RAN node-vUPF-UPF/PGW-U is established in the target 5G network in advance, which causes great signaling waste if the handover fails, and these resources also need additional signaling release.

An effective solution to the above technical problems in the related art has not been proposed.

Disclosure of Invention

Embodiments of the present invention provide a method, an apparatus, a system, and a storage medium for handover processing in a network system, so as to at least solve the above problems.

According to an embodiment of the present invention, a handover processing method of a network system is provided, including:

receiving a forwarding reset request sent by a 4G network system to a 5G network system by an Authentication Management Function (AMF) entity, wherein the forwarding reset request comprises: 4G session information;

the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the PDU session request comprises: and the PDU session request is used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF.

Optionally, after the AMF sends a packet data unit PDU session request to the selected SMF, the method further includes:

the AMF receives the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or

And the AMF reserves resources required by switching to a base station of the 5G network system and informs the 4G network system that the resources required by switching are reserved successfully.

Optionally, the method further comprises:

after the base station of the 5G network system receives the handover confirmation information sent by the terminal, the AMF receives a handover notification sent by the base station of the 5G network system, and requests to establish a channel between the base station of the 5G network system and the user plane functional entity, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; and/or

Before the base station of the 5G network system receives the handover confirmation information sent by the terminal, after receiving the 5G session information, the AMF requests to establish a channel between the base station of the 5G network system and the user plane functional entity, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C.

Optionally, the SMF comprises: the AMF receives the 5G session information obtained by processing the 4G session information at least in the following way:

the first SMF locally deduces the 5G session information according to the received 4G session information; or

And the second SMF sends the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF.

Optionally, the method further comprises:

and the third SMF sends the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF, and the first SMF and an S-GW in the 4G network system are combined network elements.

According to another embodiment of the present invention, there is also provided a handover processing method of a network system, including:

a first Session Management Function (SMF) receives a PDU session request sent by an Authentication Management Function (AMF), wherein the PDU session request comprises: the 4G session information;

the first SMF processes the 5G session information obtained by the 4G session information at least in the following way:

locally deducing to obtain the 5G session information according to the received 4G session information; or

And receiving the 5G session information sent by the second SMF, and feeding back the 5G session information to the AMF after receiving the session request sent by the AMF.

According to another embodiment of the present invention, there is also provided a handover processing apparatus for a network system, which is applied to an authentication management function AMF entity, and includes:

a first receiving module, configured to receive a forwarding reset request from a 4G network system to a 5G network system, where the forwarding reset request includes: 4G session information;

a selecting module, configured to select a session management function, SMF, and send a packet data unit, PDU, session request to the selected SMF, where the PDU session request includes: and the PDU session request is used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF.

Optionally, the apparatus further comprises:

the second receiving module is further configured to receive the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or

A reservation module, configured to reserve resources required for handover to a base station of the 5G network system;

and the notification module is used for notifying the 4G network system that resources required by switching have been reserved successfully.

According to another embodiment of the present invention, there is also provided a handover processing apparatus for a network system, which is applied to a session management function SMF, including:

a third receiving module, configured to receive a PDU session request sent by an authentication management function AMF, where the PDU session request includes: the 4G session information;

a processing module, configured to process the 5G session information obtained by the 4G session information at least in the following manner:

According to another embodiment of the present invention, there is also provided a handover processing system of a network system, including:

an Authentication Management Function (AMF) entity, configured to receive a forwarding reset request from a 4G network system to a 5G network system, select a Session Management Function (SMF), and send a Packet Data Unit (PDU) session request to the selected SMF, where the forwarding reset request includes: 4G session information, the PDU session request including: the 4G session information;

and the SMF is used for returning the 5G session information corresponding to the 4G session information to the AMF.

Optionally, the AMF is further configured to receive the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or the base station is further used for reserving resources required by the switching to the base station of the 5G network system and informing the 4G network system that the resources required by the switching have been reserved successfully.

Optionally, after the base station of the 5G network system receives the handover confirmation information sent by the terminal,

the AMF is further configured to receive a handover notification sent by the base station of the 5G network system, and request to establish a channel between the base station of the 5G network system and the user plane functional entity, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; and/or

Before the base station of the 5G network system receives the handover confirmation information sent by the terminal, the AMF is further configured to request establishment of a channel between the base station of the 5G network system and the user plane functional entity after receiving the 5G session information, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C.

Optionally, the SMF comprises: a first SMF, a second SMF, a third SMF,

the first SMF is further configured to locally derive the 5G session information according to the 4G session information; and/or

The second SMF is further configured to send the 5G session information to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving the handover request sent by the AMF;

optionally, the third SMF is further configured to send the 5G session information to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving the session request sent by the AMF, and the first SMF and an S-GW in the 4G network system are jointly configured network elements.

According to another embodiment of the present invention, there is also provided a storage medium including a stored program, wherein the program executes the handover processing method of the network system according to any one of the above.

According to another embodiment of the present invention, there is also provided a processor configured to execute a program, where the program executes the handover processing method of the network system according to any one of the above.

Through the invention, the AMF entity receives a forwarding reset request from a 4G network system to a 5G network system, the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the forwarding reset request comprises: 4G session information, the PDU session request including: the 4G session information and the PDU session request are used for indicating the SMF to return the 5G session information corresponding to the 4G session information to the AMF, and by adopting the technical scheme, the problems that in the related technology, the switching of the terminal from the 4G network system to the 5G network system fails due to large delay, and a 5G RAN node-vUPF-UPF/PGW-U media path is established in the target 5G network in advance due to the use of a plurality of signaling, and if the switching fails, a large amount of signaling is wasted are solved, so that the switching process of the terminal from the 4G network system to the 5G network system is simplified.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a prior art EPC architecture diagram;

FIG. 2 is a prior art NextGen system architecture diagram

FIG. 3 is a switching architecture diagram of a 4G network system and a 5G network system in the prior art;

FIG. 4 is a flow chart of handover from a 4G network system to a 5G network system in the prior art

Fig. 5 is a flowchart of a handover processing method of a network system according to an embodiment of the present invention;

fig. 6 is a block diagram of a configuration of a handover processing apparatus of a network system according to an embodiment of the present invention;

fig. 7 is a block diagram of an alternative configuration of a handover processing apparatus of a network system according to an embodiment of the present invention;

fig. 8 is another flowchart of a handover processing method of a network system according to an embodiment of the present invention;

fig. 9 is another configuration block diagram of a handover processing apparatus of a network system according to an embodiment of the present invention;

fig. 10 is a block diagram showing a configuration of a handover processing system of a network system according to an embodiment of the present invention;

FIG. 11 is a flow chart of an implementation in which UPF relocation does not occur in accordance with a preferred embodiment of the present invention;

FIG. 12 is a flow chart of an implementation of UPF relocation occurring in accordance with a preferred embodiment of the present invention;

FIG. 13 is a diagram illustrating an implementation of establishing a target-side media surface in accordance with a preferred embodiment of the present invention;

fig. 14 is a flow chart of an implementation of a vSMF in dynamically obtaining 5G session information in accordance with a preferred embodiment of the present invention;

fig. 15 is a flowchart of SMF/PGW-C initiating Qos flow modification after handover is completed according to the preferred embodiment of the present invention;

fig. 16 is a flow chart of the implementation of acquiring 5G session information and reassigning forwarding planes according to the preferred embodiment of the present invention.

Detailed Description

The invention will be described in detail hereinafter with reference to the accompanying drawings in conjunction with embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

Example 1

In this embodiment, a handover processing method of a network system is provided, and fig. 5 is a flowchart of a handover processing method of a network system according to an embodiment of the present invention, as shown in fig. 5, the flowchart includes the following steps:

step S102, the AMF entity receives a forwarding reset request from the 4G network system to the 5G network system, where the forwarding reset request includes: 4G session information;

step S104, the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the PDU session request comprises: the 4G session information and the PDU session request are used to instruct the SMF to return 5G session information corresponding to the 4G session information to the AMF.

Through the above steps of the present invention, the AMF entity receives a forwarding reset request from the 4G network system to the 5G network system, the AMF selects a session management function SMF, and sends a packet data unit PDU session request to the selected SMF, wherein the forwarding reset request includes: 4G session information, the PDU session request comprising: the above 4G session information and the above PDU session request are used to instruct the SMF to return the 5G session information corresponding to the above 4G session information to the AMF, and by adopting the above technical solution, the problem that in the related art, the handover of the terminal from the 4G network system to the 5G network system fails due to a large delay, and if the handover fails, a media path of the 5G RAN node-vUPF-UPF/PGW-U is established in advance in the target 5G network due to the use of many signaling, a large amount of signaling is wasted is solved, thereby simplifying the handover process of the terminal from the 4G network system to the 5G network system.

It should be noted that the SMF in the embodiment of the present invention may include, but is not limited to: SMF-T; SMF-f; a combination of SMF and PGW-C.

The AMF reserves the resources required by the switching to the base station of the 5G network system and informs the 4G network system that the resources required by the switching are reserved successfully.

In the embodiment of the present invention, after the base station of the 5G network system receives the handover confirmation information sent by the terminal, the AMF receives a handover notification sent by the base station of the 5G network system, and requests to establish a channel between the base station of the 5G network system and the user plane functional entity, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; and/or

Optionally, the SMF comprises: a first SMF (which may be understood as SMF-T), a second SMF (which may be understood as an entity combining SMF and PGW-C), and a third SMF (which may be understood as an entity combining SMF and PGW-C), where the AMF receives the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF at least in the following manner:

the first SMF locally deduces the 5G session information according to the 4G session information; or

In the process of establishing PDN connection in the 4G network system, the second SMF sends the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a switching request sent by the AMF; or

And the third SMF sends the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a session request (a handover request is also a session request) sent by the AMF, and in the 4G network system, the first SMF and the S-GW are a combined network element.

The following briefly explains the above procedure with an example:

in the process of switching from the 4G system to the 5G system, the AMF receives a 4G system switching request, where the switching request includes 4G session information (and may also include an S-GW and a PGW-C address). AMF selects one forwarding SMF-F to send a switching request. The SMF-F (corresponding to the second SMF in the above embodiment) returns the corresponding session information in the 5G system, which may include the temporary forwarding tunnel information;

after receiving the session information, the AMF informs the 4G network after completing the resource reservation to the target 5G RAN node;

after receiving the switching completion of the UE, the 5G RAN node initiates a path switching request to the AMF;

and the AMF establishes a media plane channel of the target 5G RAN node and the UPF/PGW-U by using the session information in the switching request.

Further, the method for the SMF-F to obtain the corresponding session information in the 5G system includes:

after receiving the switching request, the SMF-F locally deduces the session information in the 5G system according to the session information of the 4G; or

In the architecture of this embodiment, the S-GW and the vSMF are a converged network element. In the process of establishing PDN connection in the 4G system and in the process of establishing the special load, the SMF/PGW-C sends the corresponding 5G system session information to the vSMF through an interface between the SMF and the vSMF. After receiving the switching request, the AMF selects vSMF with the same address as the S-GW to send the switching request; or

After the UE establishes the PDN connection in the 4G system, the SMF selects a vSMF in the 5G, and dynamically sends the corresponding 5G system session information to the vSMF. And after receiving the switching request, the AMF selects the vSMF to send the switching request. SMF/PGW-C and AMF need to use the same rules to ensure that the same vSMF is selected. The specific selection rule, for example, uses the same rule to map the IP address of the UE, or the IMSI of the UE, to a vSMF.

Further, in the path switching process, the vSMF provides the 5G session information to the SMF/PGW-C, and when the SMF-PGW-C finds that the session information is mapped wrongly, the SMF/PGW-C initiates a QoS flow modification process to complete the system switching process.

Through the above description of the embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but the former is a better implementation mode in many cases. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (e.g., ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal device (e.g., a mobile phone, a computer, a server, or a network device) to execute the method according to the embodiments of the present invention.

Example 2

In this embodiment, a handover processing apparatus of a network system is further provided, and the apparatus is used to implement the foregoing embodiments, and the description of the apparatus is omitted. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated.

Fig. 6 is a block diagram of a handover processing apparatus of a network system according to an embodiment of the present invention, as shown in fig. 6, including:

1) a first receiving module 60, configured to receive a forwarding reset request from a 4G network system to a 5G network system, where the forwarding reset request includes: 4G session information;

2) a selecting module 62, configured to select a session management function SMF, and send a packet data unit PDU session request to the selected SMF, where the PDU session request includes: the 4G session information and the PDU session request are used to instruct the SMF to return 5G session information corresponding to the 4G session information to the AMF.

Through the function of the above module of the present invention, the AMF entity receives the forwarding reset request from the 4G network system to the 5G network system, the AMF selects the session management function SMF, and sends the packet data unit PDU session request to the selected SMF, wherein the forwarding reset request includes: 4G session information, the PDU session request comprising: the above 4G session information and the above PDU session request are used to instruct the SMF to return the 5G session information corresponding to the above 4G session information to the AMF, and by adopting the above technical solution, the problem that in the related art, the handover of the terminal from the 4G network system to the 5G network system fails due to a large delay, and if the handover fails, a media path of the 5G RAN node-vUPF-UPF/PGW-U is established in advance in the target 5G network due to the use of many signaling, a large amount of signaling is wasted is solved, thereby simplifying the handover process of the terminal from the 4G network system to the 5G network system.

Fig. 7 is an alternative structure block diagram of a handover processing apparatus of a network system according to an embodiment of the present invention, and as shown in fig. 7, the apparatus further includes:

a second receiving module 64, further configured to receive the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or

A reservation module 66, configured to reserve resources required for handover to a base station of the 5G network system;

a notification module 68, configured to notify that the resources required for the system handover in the 4G network have been successfully reserved.

Optionally, the second receiving module 64 is further configured to receive a handover notification sent by a base station of the 5G network system, and establish a channel between the base station of the 5G network system and the user plane functional entity according to the received 5G session information under the trigger of the handover notification, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; or

The establishing module 70 is configured to establish a channel between the base station of the 5G network system and the user plane function entity directly according to the received 5G session information and according to the received 5G session information, where the user plane function entity refers to a user plane function entity combining the UPF and the PGW-U, or a user plane function entity controlled by the SMF and the PGW-C combining function.

Example 3

According to another embodiment of the present invention, fig. 8 is another flowchart of a handover processing method of a network system according to an embodiment of the present invention, as shown in fig. 8, including:

step S202, the SMF receives a PDU session request sent by an authentication management function AMF, wherein the PDU session request comprises: the 4G session information;

step S204, the SMF processes the 5G session information obtained by the 4G session information at least in the following manner:

Through the steps, the SMF receives a PDU session request sent by an authentication management function AMF, the SMF processes the 5G session information obtained by the 4G session information at least through the above mode, and by adopting the technical scheme, the problems that in the related technology, the switching of the terminal from the 4G network system to the 5G network system fails due to large delay, and a 5G RAN node-vUPF-UPF/PGW-U media path is established in the target 5G network in advance due to the use of a lot of signaling, and great signaling waste is caused if the switching fails are solved, so that the switching process of the terminal from the 4G network system to the 5G network system is simplified.

In the embodiment of the present invention, the 5G session information is sent to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF, and the first SMF and an S-GW in the 4G network system are a combined network element.

Example 4

Fig. 9 is another block diagram of a handover processing apparatus of a network system according to an embodiment of the present invention, as shown in fig. 9, including:

a third receiving module 90, configured to receive a PDU session request sent by an authentication management function AMF, where the PDU session request includes: the 4G session information;

a processing module 92, configured to process the 5G session information obtained by the 4G session information at least in the following manner:

And receiving the 5G session information sent by the second SMF, and feeding back the 5G session information to the AMF after receiving the session request sent by the AMF. By the comprehensive action of the modules, the SMF receives a PDU session request sent by an authentication management function AMF, the SMF processes the 5G session information obtained by the 4G session information at least in the above way, and by adopting the technical scheme, the problems that in the related technology, the switching of the terminal from the 4G network system to the 5G network system fails due to large delay, and a 5G RAN node-vUPF-UPF/PGW-U media path is established in the target 5G network in advance due to the use of a lot of signaling, and if the switching fails, great signaling waste is caused are solved, and the switching process of the terminal from the 4G network system to the 5G network system is further simplified.

The processing module 92 is further configured to send the 5G session information to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF, and the first SMF and an S-GW in the 4G network system are jointly configured network elements.

Example 5

In an embodiment of the present invention, a system for processing handover of a network system is further provided, and fig. 10 is a block diagram of a structure of the system for processing handover of the network system according to the embodiment of the present invention, as shown in fig. 10, including:

an AMF entity 80, configured to receive a forwarding reset request from a 4G network system to a 5G network system, select a session management function SMF, and send a PDU session request to the selected SMF, where the forwarding reset request includes: 4G session information, the PDU session request comprising: the 4G session information;

the SMF 82 is configured to return 5G session information corresponding to the 4G session information to the AMF.

Through the interaction of the switching processing system of the network system of the embodiment of the invention, the AMF entity receives a forwarding reset request from the 4G network system to the 5G network system, the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the forwarding reset request comprises: 4G session information, the PDU session request comprising: the above 4G session information and the above PDU session request are used to instruct the SMF to return the 5G session information corresponding to the above 4G session information to the AMF, and by adopting the above technical solution, the problem that in the related art, the handover of the terminal from the 4G network system to the 5G network system fails due to a large delay, and if the handover fails, a media path of the 5G RAN node-vUPF-UPF/PGW-U is established in advance in the target 5G network due to the use of many signaling, a large amount of signaling is wasted is solved, thereby simplifying the handover process of the terminal from the 4G network system to the 5G network system.

Optionally, the AMF is further configured to receive the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or the base station is further configured to reserve resources required for handover to the base station of the 5G network system, and notify that the resources required for handover of the 4G network system have been successfully reserved.

Optionally, the SMF comprises: a first SMF, a second SMF, a third SMF,

The second SMF is further configured to send the 5G session information to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving the session request sent by the AMF.

Optionally, the third SMF is further configured to send the 5G session information to the first SMF, where the first SMF feeds back the 5G session information to the AMF after receiving the session request sent by the AMF, and in the 4G network system, the first SMF and the S-GW are a combined network element.

In an embodiment of the present invention, a processor is further provided, where the processor is configured to execute a program, where the program executes the handover processing method of the network system according to any one of the foregoing descriptions.

The following description is given in conjunction with the preferred embodiments, which combine the above embodiments and their preferred embodiments.

Preferred embodiment 1

Fig. 11 is a flow chart of the implementation of the UPF relocation not occurring according to the preferred embodiment of the present invention, as shown in fig. 11, including the following steps:

step S500, the terminal UE establishes PDN connection in the 4G system, and may also establish a dedicated bearer;

step S501, a source 4G RAN node (eNB) finds that switching to 5G is needed, and sends a switching request to MME, wherein the switching request carries target cell information;

step S502, MME selects a target AMF according to the switching Request, and sends a Forward location Request to the AMF, wherein the Forward location Request carries 4G session information, including PGW-C/SMF, S-GW address, bearing information and the like;

step S503, AMF selects an SMF-F, and initiates PDU Session Request to it, wherein 4G Session information is carried. The SMF-F may be a visited-site specific SMF or an SMF co-located with the S-GW.

And step S504, the SMF-F establishes an N4session to the UPF-F to acquire N3 uplink tunnel information. SMF-F returns PDU Session Response to AMF, wherein the PDU Session information carries corresponding 5G PDU Session information and the uplink tunnel information of N3. The information is 5G session information generated by SMF-F using 4G session information mapping, or 5G session information obtained using fig. 13;

step S505: and the AMF sends a Handover Request to the 5G RAN node, wherein 5G PDU session information and N3 uplink tunnel information.

Step S506: the 5G RAN node sends a Handover Request acknowledgement to the AMF, wherein the Handover Request acknowledgement comprises N3 downlink tunnel information;

step S507, the AMF sends a PDU Session modification Request to the SMF-F to Request to establish a downlink forwarding tunnel;

step S508, SMF-F returns response to AMF, including forwarding tunnel information;

step S509: the AMF sends a Forward Relocation Response to the MME, wherein the Forward Relocation Response comprises information such as Serving GW change indication, EPS Bearer Setup List, TEIDs and the like;

step S510: MME sends a Create index Data Forwarding Tunnel Request to S-GW to Request the establishment of a temporary Forwarding Tunnel.

Step S511: MME sends Handover Command to 4G RAN node, wherein temporary forwarding tunnel and bearing information are included

Step S512: the 4G RAN (eNB) sends a Handover Command to the UE, wherein the Handover Command comprises wireless information of a target 5G RAN;

step S513: and the UE accesses the target 5G RAN node according to the received 5G RAN wireless information and sends a Handover Confirm to the 5G RAN node.

At the moment, after the downlink data reaches the 4G RAN node, the downlink data passes through the S-GW, the UPF-F and the 5G RAN node through the forwarding tunnel and reaches the UE;

after step S508, when the UE is handed over to the 5G system, uplink data can reach the UPF-F, and steps S514 to S519 are intended to establish a media plane channel from the UPF-F to the PGW-U/UPF. Step S514 may be in the same message as step S507, and step S515 may be sent after step S508. Step S514 may also be a separate message sent after step S509. In this embodiment, a mode in fig. 13 is used, and in addition, a mode in fig. 13 b may also be used, and after receiving the Handover notification in step S520, the establishment of the media plane is triggered. The embodiment adopting the mode b in fig. 13 will not be described again.

Step S514: the AMF sends a PDU session handover request to the SMF-F

Step S515: and the SMF-F and the UPF-F interact to obtain N9 downlink tunnel information, and then a PDU session handover request is sent to the SMF/PGW-C, wherein the PDU session handover request carries the N9 downlink tunnel information.

Step S516: if PCC is deployed, SMF CAN initiate PDU-CAN Session Modification to PCF/PCRF to obtain 5GS PCC rule of PDU Session after switching to 5G.

Step S517: the SMF/PGW-C initiates N4session modification to the UPF/PGW-U, informs the N9 downlink tunnel information of the SMF/PGW-U, and obtains N9 uplink tunnel information;

step S518: the SMF/PGW-C sends PDU Session Handover Response to the SMF-F, wherein the PDU Session Handover Response carries the information of the N9 uplink tunnel;

step S519: the SMF-F informs the UPF-F of the uplink tunnel information of the N9 and sends a PDU Session Handover Response to the AMF;

step S520: 5G RAN node sends Handover Notify to AMF

Step S521: and the AMF sends a Forward Relocation Complete Notification message to the MME to confirm that the handover is completed.

Step S522: and the AMF sends a Handover Complete message to the SMF/PGW-C through the SMF-F.

Step S523: and the SMF/PGW-C informs the UPF/PGW-U, and the UPF/PGW-U sends the downlink data to the target side at the moment.

Step S524: SMF/PGW-C sends Handover Complete Ack to AMF.

step S503, a PDU session driver request needs to be sent to the SMF-F selected for each PDN connection; these SMF-Fs may be the same entity

Step S504, after all responses need to be received, initiating step S505;

step S507, a Modify PDU session request needs to be sent to SMF-F for each PDN connection;

step S508, after all responses need to be received, sending a step S509 message to the MME;

step S514, a PDU Session Handover Request needs to be initiated for each PDN connection.

In step S522, a Handover Complete message needs to be sent to each SMF/PGW-C.

Preferred embodiment two

Fig. 12 is a flow chart of an implementation of UPF relocation according to the preferred embodiment of the present invention, as shown in fig. 12.

Step S600, the terminal UE establishes PDN connection in the 4G system, and possibly establishes a dedicated bearer;

step S601, a source 4G RAN node (eNB) finds that switching to 5G is needed, and sends a switching request to MME, wherein the switching request carries target cell information;

step S602, MME selects a target AMF according to the switching Request, and sends a Forward location Request to the AMF, wherein the Forward location Request carries 4G session information, including PGW-C/SMF, S-GW address, bearing information and the like;

step S603, the AMF selects an SMF-F, and initiates a PDU Session Request to the SMF, where the PDU Session Request carries 4G Session information. The SMF-F may be a visited-site specific SMF or an SMF co-located with the S-GW.

And step S604, the SMF-F establishes an N4session to the UPF-F to acquire N3 uplink tunnel information. SMF-F returns PDU Session Response to AMF, wherein the PDU Session information carries corresponding 5G PDU Session information and the uplink tunnel information of N3. The information is 5G session information generated by SMF-F using 4G session information mapping, or 5G session information obtained using fig. 13;

step S605: and the AMF sends a Handover Request to the 5G RAN node, wherein 5G PDU session information and N3 uplink tunnel information.

Step S606: the 5G RAN node sends a Handover Request acknowledgement to the AMF, wherein the Handover Request acknowledgement comprises N3 downlink tunnel information;

step S607, AMF sends PDU Session modify Request to SMF-F, requesting to establish downlink forwarding tunnel;

step S608, SMF-F returns response to AMF, which contains forwarding tunnel information;

step S609: the AMF sends a Forward Relocation Response to the MME, wherein the Forward Relocation Response comprises information such as Serving GW change indication, EPS Bearer Setup List, TEIDs and the like;

step S610: MME sends a Create index Data Forwarding Tunnel Request to S-GW to Request the establishment of a temporary Forwarding Tunnel.

Step S611: MME sends Handover Command to 4G RAN node, wherein temporary forwarding tunnel and bearing information are included

Step S612: the 4G RAN (eNB) sends a Handover Command to the UE, wherein the Handover Command comprises wireless information of a target 5G RAN;

step S613: and the UE accesses the target 5G RAN node according to the received 5G RAN wireless information and sends a Handover Confirm to the 5G RAN node.

the SMF-F only realizes the temporary downlink data forwarding, and the steps S614 to S619 and S621 aim to establish a media plane channel from the 5G RAN, the UPF-F to the PGW-U/UPF. Step S614 may be sent after step S609. In this embodiment, a mode in fig. 13 is used, and in addition, a mode in fig. 13 b may also be used, after receiving the Handover notification in step S620, the establishment of the media plane is triggered, and at this time, step S621 sends the media plane after step S625. The embodiment adopting the mode b in fig. 13 will not be described again.

Step S614: the AMF selects t-SMF, and sends PDU session handover request to the t-SMF, wherein the PDU session handover request carries N3 downlink tunnel information;

step S615: and (3) interacting t-SMF and t-UPF to obtain N3 uplink tunnel information and N9 downlink tunnel information, and then sending a PDU session handover request to SMF/PGW-C, wherein the PDU session handover request carries the N9 downlink tunnel information.

Step S616: if PCC is deployed, SMF CAN initiate PDU-CAN Session Modification to PCF/PCRF to obtain 5GS PCC rule of PDU Session after switching to 5G.

Step S617: the SMF/PGW-C initiates N4session modification to the UPF/PGW-U, informs the N9 downlink tunnel information of the SMF/PGW-U, and obtains N9 uplink tunnel information;

step S618: the SMF/PGW-C sends PDU Session Handover Response to the t-SMF, wherein the PDU Session Handover Response carries the information of the N9 uplink tunnel;

step S619: the t-SMF informs the t-UPF of the N9 uplink tunnel information, and sends a PDU Session Response to the AMF, wherein the PDU Session Response carries the N3 uplink tunnel information;

step S620: 5G RAN node sends Handover Notify to AMF

Step S621: the AMF informs the N3 of the uplink tunnel information to the 5G RAN node;

step S622: and the AMF sends a Forward Relocation Complete Notification message to the MME to confirm that the handover is completed.

Step S623: and the AMF sends a Handover Complete message to the SMF/PGW-C through the t-SMF.

Step S624: and the SMF/PGW-C informs the UPF/PGW-U, and the UPF/PGW-U sends the downlink data to the t-UPF at the moment.

Step S625: SMF/PGW-C sends Handover Complete Ack to AMF.

The subsequent steps also include that the UE initiates a registration process in the 5G network, the MME releases 4G network resources, and the AMF releases SMF-F.

step S603, a PDU session handover request needs to be sent to the SMF-F selected for each PDN connection; these SMF-Fs may be the same entity

Step S604, after all responses need to be received, initiating step S605;

step S607, need to send the modification PDU session request to SMF-F for each PDN connection;

step S608, after all responses need to be received, sending a message of step S609 to the MME;

step S614, a PDU Session Handover Request needs to be initiated for each PDN connection.

Step S621: the AMF informs the 5G RAN nodes of N3 tunnel uplink information corresponding to all PDU sessions;

step S623, a Handover Complete message needs to be sent to each SMF/PGW-C.

Preferred embodiment three

FIG. 13 is a diagram illustrating an implementation of creating a target-side media surface according to a preferred embodiment of the present invention, as shown in FIG. 13;

mode a is the embodiment of fig. 11 and 12. Before the switching is completed, the media plane channel of the target side is already completely established, and the specific steps are as shown in fig. 11 and fig. 12;

and b, triggering to establish the media plane channel after receiving the Handover notify of the 5G RAN node. The flow before step S720 is the same as before steps S520, S620 in fig. 11 and 12, except that there are no steps S514 to S519, and S614 to S619.

Step S721: the 5G RAN node sends a Handover Notify to the AMF;

step S722: the AMF selects t-SMF, and sends PDU session handover request to the t-SMF, wherein the PDU session handover request carries N3 downlink tunnel information;

step S723: and (3) interacting t-SMF and t-UPF to obtain N3 uplink tunnel information and N9 downlink tunnel information, and then sending a PDU session handover request to SMF/PGW-C, wherein the PDU session handover request carries the N9 downlink tunnel information.

Step S724: if PCC is deployed, SMF CAN initiate PDU-CAN Session Modification to PCF/PCRF to obtain 5GS PCC rule of PDU Session after switching to 5G.

Step S725: the SMF/PGW-C initiates N4session modification to the UPF/PGW-U, informs the N9 downlink tunnel information of the SMF/PGW-U, and obtains N9 uplink tunnel information; at this time, the downlink media is sent to the t-UPF;

step S726: the SMF/PGW-C sends PDU Session Handover Response to the t-SMF, wherein the PDU Session Handover Response carries the information of the N9 uplink tunnel;

step S727: the t-SMF informs the t-UPF of the N9 uplink tunnel information, and sends a PDU Session Response to the AMF, wherein the PDU Session Response carries the N3 uplink tunnel information;

step S728: the AMF informs the N3 of the uplink tunnel information to the 5G RAN node;

after receiving the switching request, the SMF-F locally deduces the session information in the 5G system according to the session information of the 4G. Or dynamically obtained from SMF/PGW-C.

Preferred embodiment four

Fig. 14 is a flow chart of an implementation of a vSMF in dynamically obtaining 5G session information in accordance with a preferred embodiment of the present invention. Wherein, the S-GW and the vSMF are a combined network element. In the process of establishing PDN connection in the 4G system and in the process of establishing the special load, the SMF/PGW-C sends the corresponding 5G system session information to the vSMF through an interface between the SMF and the vSMF. After receiving the switching request, the AMF selects vSMF with the same address as the S-GW to send the switching request; or

Step S800, the terminal UE establishes PDN connection in the 4G system;

step S801, the SMF/PGW-C sends 5G session information to the selected Vsmf;

step S802, the terminal UE generates the processes of establishing, modifying and deleting the special bearing in the 4G system;

step S803, SMF/PGW-C sends the 5G session information to the selected vSMF;

step S804, the S-GW changes;

step S805, SMF/PGW-C sends 5G session information to target vSMF, or

Step S805a, the source vSMF sends 5G session information to the target vSMF;

here, the vSMF and the S-GW may be a co-located network element, or may be a specific vSMF. When it is a certain vSMF, steps S805 and S805a are not present.

In the preferred embodiment of the present invention, the SMF-F may locally map the 4G session information to the 5G session information, but if the mapping is wrong, after the handover is completed, the SMF/PGW-C initiates the Qos flow modification procedure to modify.

Preferred embodiment five

Fig. 15 is a flowchart of initiating Qos flow modification by the SMF/PGW-C after handover is completed according to the preferred embodiment of the present invention, and taking the above fig. 14 as an example, the difference between the step S914 and the corresponding functional steps is as follows:

step S906, the SMF/PGW-C finds that the 5G session information is wrong;

step S915: after the switching is finished, the SMF/SMF/PGW-C initiates a Qos flow modification to the t-SMF/t-UPF; and (5) interacting the t-SMF and the t-UPF to finish modification. The T-SMF sends a Qos flow modification to the AMF;

step S916: AMF initiates session modification to 5G RAN;

step S917: the 5G RAN may initiate RRC reconfiguration;

step S918: the 5G RAN node sends a response to the AMF;

step S919: and the AMF sends a response of session modification to the SMF/PGW-C.

Preferred embodiment six

Fig. 16 is a flowchart of an implementation of obtaining 5G session information and reassigning a forwarding plane according to a preferred embodiment of the present invention, as shown in fig. 16, including:

step S1600, the terminal UE has already established a PDN connection in the 4G system, and may also establish a dedicated bearer;

step S1601, a source 4G RAN node (eNB) finds that switching to 5G is needed, and sends a switching request to MME, wherein the switching request carries target cell information;

step S1602, the MME selects a target AMF according to the switching Request, and sends a Forward location Request to the AMF, wherein the Forward location Request carries 4G session information, including PGW-C/SMF, S-GW address, bearing information and the like;

step S1603, AMF selects an SMF-T, and initiates a PDU Session Request to the SMF-T, wherein the PDU Session Request carries 4G Session information. The SMF-T may be a visitor specific SMF or an SMF co-located with the S-GW.

And step S1604, the SMF-T establishes an N4session to the UPF-T, and obtains N3 uplink tunnel information. SMF-F returns PDU Session Response to AMF, wherein the PDU Session information carries corresponding 5G PDU Session information and the uplink tunnel information of N3. The information is 5G session information generated by SMF-T using 4G session information mapping, or 5G session information obtained using fig. 14;

step S1605: and the AMF sends a Handover Request to the 5G RAN node, wherein 5G PDU session information and N3 uplink tunnel information.

Step S1606: the 5G RAN node sends a Handover Request acknowledgement to the AMF, wherein the Handover Request acknowledgement comprises N3 downlink tunnel information;

step S1607, the AMF establishes a temporary forwarding tunnel. The AMF selects a forwarding SMF-F, sends a PDU Session forward tunnel Request and requests to establish a downlink forwarding tunnel;

step S1608, SMF-F controls UPF-F, generates downlink forwarding information, returns response to AMF, including forwarding tunnel information;

step S1609: the AMF sends a Forward Relocation Response to the MME, wherein the Forward Relocation Response comprises information such as Serving GW change indication, EPS Bearer Setup List, TEIDs and the like;

step S1610: MME sends a Create index Data Forwarding Tunnel Request to S-GW to Request the establishment of a temporary Forwarding Tunnel.

Step S1611: the MME sends a Handover Command to the 4G RAN node, wherein the Handover Command comprises a temporary forwarding tunnel and bearing information;

step S1612: the 4G RAN (eNB) sends a Handover Command to the UE, wherein the Handover Command comprises wireless information of a target 5G RAN;

step S1613: and the UE accesses the target 5G RAN node according to the received 5G RAN wireless information and sends a Handover Confirm to the 5G RAN node.

the SMF-F only realizes the temporary downlink data forwarding, and the steps S1614 to S1619 aim to establish a media plane channel from the 5G RAN, UPF-t to the PGW-U/UPF. Step S1614 may be sent after step S1609. In this embodiment, a mode in fig. 13 is used, and in addition, a mode in fig. 13 b may also be used, and after receiving the Handover notify in step S1620, the establishment of the media plane channel from the UPF-t to the PGW-U/UPF is completed. The embodiment adopting the mode b in fig. 13 will not be described again.

Step S1614: the AMF sends a PDU session modify request to the t-SMF;

step S1615: and interacting t-SMF and t-UPF to obtain N9 downlink tunnel information, and then sending a PDU session request to SMF/PGW-C, wherein the PDU session request carries the N9 downlink tunnel information.

Step S1616: if PCC is deployed, SMF CAN initiate PDU-CAN Session Modification to PCF/PCRF to obtain 5GS PCC rule of PDU Session after switching to 5G.

Step S1617: the SMF/PGW-C initiates N4session modification to the UPF/PGW-U, informs the N9 downlink tunnel information of the SMF/PGW-U, and obtains N9 uplink tunnel information;

step S1618: the SMF/PGW-C sends PDU Session Response to the t-SMF, wherein the PDU Session Response carries the information of the N9 uplink tunnel;

step S1619: the t-SMF informs the t-UPF of the uplink tunnel information of the N9 and sends PDU Session Response to the AMF;

step S1620: the 5G RAN node sends a Handover Notify to the AMF;

step S1621: and the AMF sends a Forward Relocation Complete Notification message to the MME to confirm that the handover is completed.

Step S1622: and the AMF sends a Handover Complete message to the SMF/PGW-C through the t-SMF.

Step S1623: and the SMF/PGW-C informs the UPF/PGW-U, and the UPF/PGW-U sends the downlink data to the t-UPF at the moment.

Step S1624: SMF/PGW-C sends Handover Complete Ack to AMF.

step S1603, a PDU session request needs to be sent to the SMF-T selected for each PDN connection; these SMF-T may be the same entity

Step S1604, after all responses need to be received, initiating step S1605;

step S1607, a PDU session forward channel request is sent to SMF-F for each PDN connection;

step S1608, after receiving all the responses, sending a step S1609 message to the MME;

step S1614, a PDU Session modify Request needs to be initiated for each PDN connection.

In step S1622, a Handover Complete message needs to be sent to each SMF/PGW-C.

Example 4

An embodiment of the present invention further provides a storage medium including a stored program, where the program executes any one of the methods described above.

Alternatively, in the present embodiment, the storage medium may be configured to store program codes for performing the following steps:

s1, the AMF entity receives a forwarding reset request from the 4G network system to the 5G network system, where the forwarding reset request includes: 4G session information;

s2, the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the PDU session request comprises: and the PDU session request is used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF.

Optionally, the storage medium is further arranged to store program code for performing the steps of:

s3, the AMF receives the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or

s4, after receiving the handover confirmation information sent by the terminal, the base station of the 5G network system receives a handover notification sent by the base station of the 5G network system, and requests to establish a channel between the base station of the 5G network system and the user plane function entity, where the user plane function refers to a combined function of a user plane function entity UPF and a PGW-U, or a user plane function entity controlled by a combined function of an SMF and a PGW-C; and/or

Before the base station of the 5G network system receives the handover confirmation information sent by the terminal, the AMF is further configured to request establishment of a channel between the base station of the 5G network system and the user plane functional entity after receiving the 5G session information, where the channel refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C

Optionally, in this embodiment, the storage medium may include, but is not limited to: various media capable of storing program codes, such as a usb disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a removable hard disk, a magnetic disk, or an optical disk.

It will be apparent to those skilled in the art that the modules or steps of the present invention described above may be implemented by a general purpose computing device, they may be centralized on a single computing device or distributed across a network of multiple computing devices, and alternatively, they may be implemented by program code executable by a computing device, such that they may be stored in a storage device and executed by a computing device, and in some cases, the steps shown or described may be performed in an order different than that described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple ones of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for handover processing in a network system, comprising:

the AMF selects a Session Management Function (SMF) and sends a Packet Data Unit (PDU) session request to the selected SMF, wherein the PDU session request comprises: the 4G session information, the PDU session request is used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF;

wherein the SMF comprises: the AMF receives the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF in the following modes: and in the process of establishing PDN connection in a 4G network system, the second SMF sends the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF.

2. The method of claim 1, wherein after the AMF sends a Packet Data Unit (PDU) session request to the selected SMF, the method further comprises:

3. The method of claim 1, further comprising:

after a base station of the 5G network system receives switching confirmation information sent by a terminal, the AMF receives a switching notification sent by the base station of the 5G network system and requests to establish a channel between the base station of the 5G network system and a user plane functional entity, wherein the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; and/or

4. The method of claim 1, further comprising:

5. A method for handover processing in a network system, comprising:

a first Session Management Function (SMF) receives a PDU session request sent by an Authentication Management Function (AMF), wherein the PDU session request comprises: 4G session information;

the first SMF processes the 5G session information obtained by the 4G session information in the following way:

and in the PDN connection establishment process of the 4G network system, receiving 5G session information sent by a second SMF, and after receiving a session request sent by the AMF, feeding back the 5G session information to the AMF.

6. A handover processing device of a network system, applied to an Authentication Management Function (AMF) entity, comprises:

a selecting module, configured to select a session management function, SMF, and send a packet data unit, PDU, session request to the selected SMF, where the PDU session request includes: the 4G session information, the PDU session request is used for indicating the SMF to return 5G session information corresponding to the 4G session information to the AMF;

7. The apparatus of claim 6, further comprising:

8. A handover processing device of a network system, applied to a Session Management Function (SMF), comprises:

a third receiving module, configured to receive a PDU session request sent by an authentication management function AMF, where the PDU session request includes: 4G session information;

a processing module, configured to process the 5G session information obtained by the 4G session information in the following manner:

9. A handover processing system of a network system, comprising:

the SMF is used for returning 5G session information corresponding to the 4G session information to the AMF;

the SMF includes: the first SMF, the second SMF and the third SMF are further used for sending the 5G session information to the first SMF in the process of establishing PDN connection in a 4G network system, wherein the first SMF feeds back the 5G session information to the AMF after receiving a switching request sent by the AMF.

10. The system of claim 9, wherein the AMF is further configured to receive the 5G session information obtained by processing the 4G session information by the SMF returned by the SMF; and/or the base station is further used for reserving resources required by the switching to the base station of the 5G network system and informing the 4G network system that the resources required by the switching have been reserved successfully.

11. The system according to claim 9, wherein after the base station of the 5G network system receives the switching confirmation message transmitted by the terminal,

the AMF is further configured to receive a handover notification sent by the base station of the 5G network system, and request to establish a channel between the base station of the 5G network system and a user plane functional entity, where the user plane functional entity refers to a combined function of a user plane functional entity UPF and a PGW-U, or a user plane functional entity controlled by a combined function of an SMF and a PGW-C; and/or

Before the base station of the 5G network system receives the handover confirmation information sent by the terminal, the AMF is further configured to request to establish a channel between the base station of the 5G network system and the user plane function entity after receiving the 5G session information, where the user plane function entity refers to a combined function of a user plane function entity UPF and a PGW-U, or a user plane function entity controlled by a combined function of an SMF and a PGW-C.

12. The system of claim 9, wherein the third SMF is further configured to send the 5G session information to the first SMF, wherein the first SMF feeds back the 5G session information to the AMF after receiving a session request sent by the AMF, and wherein the first SMF and an S-GW in the 4G network system are jointly configured network elements.

13. A storage medium characterized by comprising a stored program, wherein the program executes a handover processing method of the network system according to any one of claims 1 to 4 or a handover processing method of the network system according to claim 5 when executed.

14. A processor, configured to execute a program, wherein the program executes to perform the handover processing method of the network system according to any one of claims 1 to 4 or the handover processing method of the network system according to claim 5.