CN110475299B

CN110475299B - Method and device for switching cells

Info

Publication number: CN110475299B
Application number: CN201810444773.7A
Authority: CN
Inventors: 黄晓舸; 张东宇; 张晨璐; 郑倩
Original assignee: Vivo Mobile Communication Co Ltd
Current assignee: Vivo Mobile Communication Co Ltd
Priority date: 2018-05-10
Filing date: 2018-05-10
Publication date: 2021-06-29
Anticipated expiration: 2038-05-10
Also published as: CN110475299A

Abstract

The embodiment of the invention provides a method and a device for switching cells, relates to the technical field of communication, and is used for solving the problems that in the process of switching cells, user data forwarding needs to go to and fro a core network, the forwarding process is complex, and the sending efficiency of user data is not improved. The method comprises the following steps: receiving a switching confirmation message sent by a target base station through core network equipment, wherein the switching confirmation message is used for confirming that the UE is switched from a source cell to a target cell; and sending a switching command to the UE, and sending first data to the target base station through the MEC server, wherein the switching command is used for indicating the UE to be switched from a source cell to the target cell, the source cell is a cell served by the source base station, the target cell is a cell served by the target base station, and the first data is user data which is sent to the source base station by the core network equipment and is not sent to the UE by the source base station. The embodiment of the invention is used for switching the cell.

Description

Method and device for switching cells

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for cell handover.

Background

With the rapid development of mobile internet and internet of things and the continuous emergence of various novel services, mobile data traffic is explosively increased, and the cell radius of a cellular mobile network is continuously reduced to meet ultrahigh data requirements. Due to the reduction of the cell radius of cellular mobile networks, User Equipment (UE) often needs to be handed over from a cell of one cellular mobile network to a cell of another cellular mobile network during mobility.

The conventional procedure for switching cells generally includes: the method comprises four parts of switching measurement processing, switching decision, switching preparation and switching execution. When there is no X2 interface between a source base station (a base station currently serving the UE) and a target base station (a base station that will serve the UE after the communication system is handed over), or an Evolved Packet Core (EPC) node (mobility manager or serving gateway) is changed, a handover procedure is initiated to the target base station using an S1 interface, or the source base station initiates that the X2 interface is rejected, the communication system is handed over based on the S1 interface. In the process of cell switching based on the S1 interface, the source base station is required to stop sending user Data to the UE, and forward the received user Data that has not been sent to the UE to a Packet Data Convergence Protocol (PDCP) buffer in the core network, the user Data in the PDCP buffer is forwarded to a source Serving Gateway (S-GW) via a Data tunnel, then the source S-GW forwards the user Data to a target S-GW via the Data tunnel, and then the target S-GW forwards the user Data to the target base station via the Data tunnel. In the process of cell switching based on the S1 interface, user data forwarding needs to go to and fro the core network, and the forwarding process is complex, which is not favorable for improving data transmission efficiency.

Disclosure of Invention

The embodiment of the invention provides a method and a device for switching cells, which are used for solving the problems that in the process of switching the cells, user data forwarding needs to go to and fro a core network, the forwarding process is complex, and the sending efficiency of the user data is not improved.

In order to solve the technical problem, the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a method for switching a cell, where the method is used for a source base station, and the method includes:

receiving a switching confirmation message sent by a target base station through core network equipment, wherein the switching confirmation message is used for confirming that User Equipment (UE) is switched from a source cell to a target cell;

sending a handover command to the UE, and sending first data to the target base station through a mobile edge computing MEC server, where the handover command is used to instruct the UE to handover from the source cell to the target cell, the source cell is a cell served by the source base station, the target cell is a cell served by the target base station, and the first data is user data that has been sent to the source base station by the core network device and is not sent to the UE by the source base station.

In a second aspect, an embodiment of the present invention provides a method for switching a cell, where the method is used for an MEC server, and the method includes:

receiving first data sent by a source base station, wherein the first data is user data which is sent to the source base station by core network equipment and is not sent to User Equipment (UE) by the source base station;

sending and sending the first data to the target base station;

the source base station is a base station serving a cell accessed by the UE before cell switching, and the target base station is a base station serving a cell accessed by the UE after cell switching.

In a third aspect, an embodiment of the present invention provides a method for cell handover, which is applied to a target base station, and the method includes:

sending a switching confirmation message to a source base station through core network equipment;

receiving first data sent by the source base station through a Mobile Edge Computing (MEC) server;

the handover confirmation message is used to confirm that a User Equipment (UE) is handed over from a source cell to a target cell, the source cell is a cell served by the source base station, the target cell is a cell served by the target base station, and the first data is user data which has been sent to the source base station by the core network device and is not sent to the UE by the source base station.

In a fourth aspect, an embodiment of the present invention provides a method for switching a cell, where the method is applied to a source AMF, and the method includes:

receiving a switching request message sent by a source base station, wherein the switching request message is used for requesting to switch User Equipment (UE) from a source cell to a target cell;

sending the switching request message to the target base station through a target AMF;

receiving a switching confirmation message sent by the target base station through the target AMF; the handover confirmation message is used to confirm handover of the UE from the source cell to the target cell;

sending the handover confirmation message to the source base station;

wherein the source cell is a cell served by the source base station, the target cell is a cell served by the target base station, and the handover request message includes: a first mapping relationship; the first mapping relationship is: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

In a fifth aspect, an embodiment of the present invention provides a method for cell handover, which is applied to a target AMF, and the method includes:

receiving a switching request message sent by a source base station through a source AMF, wherein the switching request message is used for requesting to switch User Equipment (UE) from a source cell to a target cell;

sending the handover request message to the target base station;

receiving a handover confirmation message sent by the target base station, where the handover confirmation message is used to confirm that the UE is handed over from the source cell to the target cell;

the handover confirm message is sent to the source base station through the source AMF;

In a sixth aspect, an embodiment of the present invention provides a base station, including:

a receiving unit, configured to receive a handover confirmation message sent by a target base station through core network equipment, where the handover confirmation message is used to confirm that a user equipment UE is handed over from a cell served by the base station to a target cell;

a sending unit, configured to send a handover command to the UE, and send first data to the target base station through a mobile edge computing MEC server, where the handover command is used to instruct the UE to handover from a cell served by the base station to the target cell, the target cell is a cell served by the target base station, and the first data is user data that has been sent to the source base station by the core network device and is not sent to the UE by the source base station.

In a seventh aspect, an embodiment of the present invention provides an MEC server, including: a receiving unit, configured to receive first data sent by a source base station, where the first data is user data that has been sent to the source base station by a core network device and is not sent to a user equipment UE by the source base station;

a sending unit, configured to send and send the first data to the target base station;

In an eighth aspect, an embodiment of the present invention provides a base station, including:

a sending unit, configured to send a handover confirmation message to a source base station through core network equipment;

a receiving unit, configured to receive first data sent by the source base station through a mobile edge computing MEC server;

the handover confirmation message is used to confirm that a User Equipment (UE) is handed over from a source cell to a cell served by the base station, the source cell is the cell served by the source base station, and the first data is user data which is sent to the source base station by the core network device and is not sent to the UE by the source base station.

In a ninth aspect, an embodiment of the present invention provides an AMF, including:

a receiving unit, configured to receive a handover request message sent by a source base station, where the handover request message is used to request that a user equipment UE be handed over from a source cell to a target cell;

a sending unit, configured to send the handover request message to the target base station through a target AMF;

the receiving unit is further configured to receive a handover confirmation message sent by the target base station through the target AMF; the handover confirmation message is used to confirm handover of the UE from the source cell to the target cell;

the sending unit is further configured to send the handover confirmation message to the source base station;

In a tenth aspect, an embodiment of the present invention provides an AMF, including:

In an eleventh aspect, an embodiment of the present invention provides a base station, including: a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the method of handing over a cell as set forth in the first or third aspect.

In a twelfth aspect, an embodiment of the present invention provides an MEC server, including: a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the method of handing over a cell according to the second aspect.

In a thirteenth aspect, an embodiment of the present invention provides an AMF, including: a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the method of handing over a cell as set forth in the fourth or fifth aspect.

In a fourteenth aspect, an embodiment of the present invention provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and the computer program, when executed by a processor, implements the steps of the method for handing over a cell according to any one of the first, second, third, fourth, and fifth aspects.

The method for switching cells, provided by an embodiment of the present invention, sends a handover command to a UE after receiving a handover confirmation message sent by a target base station through a core network device, and sends first data to the target base station through an MEC server, where the handover command is used to instruct the UE to switch from a source cell to the target cell, the first data is user data that the core network device has sent to the source base station and the source base station has not sent to the UE, that is, after instructing the UE to switch from the source cell to the target cell, the user data that the core network device has sent to the source base station and the source base station has not sent to the UE is sent to the target base station through the MEC server, and compared with the prior art in which user data forwarding needs to go to and return to the core network during cell handover, the method for switching cells provided by an embodiment of the present invention, the user data is forwarded through the MEC server, so that the user data can be prevented from going to and going to a core network in the forwarding process, and the sending efficiency of the user data can be improved.

Drawings

Fig. 1 is a schematic diagram of a possible structure of a communication system according to an embodiment of the present invention;

fig. 2 is a flowchart illustrating a method for handing over a cell according to an embodiment of the present invention;

fig. 3 is a second flowchart illustrating a method for handing over a cell according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an MEC server provided in an embodiment of the present invention;

fig. 6 is a schematic structural diagram of another base station according to an embodiment of the present invention;

FIG. 7 is a schematic block diagram of an AMF provided by an embodiment of the present invention;

FIG. 8 is a schematic block diagram of another AMF provided by an embodiment of the present invention;

fig. 9 is a schematic diagram of a hardware structure of a base station according to an embodiment of the present invention;

fig. 10 is a schematic diagram of a hardware structure of an MEC according to an embodiment of the present invention;

fig. 11 is a schematic diagram of a hardware structure of an AMF according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship; in the formula, the character "/" indicates that the preceding and following related objects are in a relationship of "division". The term "plurality" herein means two or more, unless otherwise specified.

For the convenience of clearly describing the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, the words "first", "second", and the like are used to distinguish the same items or similar items with basically the same functions or actions, and those skilled in the art can understand that the words "first", "second", and the like do not limit the quantity and execution order.

In the embodiments of the present invention, words such as "exemplary" or "for example" are used to mean serving as examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "e.g.," an embodiment of the present invention is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present concepts related in a concrete fashion. In the embodiments of the present invention, the meaning of "a plurality" means two or more unless otherwise specified.

In the process of cell switching based on the S1 interface, the source base station is required to stop sending user data to the UE, and to forward the received user data that has not been sent to the UE to the PDCP buffer in the core network, the user data in the PDCP buffer is forwarded to the source S-GW through the data tunnel, then the source S-GW forwards the user data to the target S-GW through the data tunnel, and then the target S-GW forwards the user data to the target base station through the data tunnel, the user data forwarding needs to go to and from the core network, the forwarding flow is complex, and it is not beneficial to improve the data sending efficiency.

In order to solve the above problem, an embodiment of the present invention provides a method and an apparatus for handing over a cell, where, after receiving a handover confirmation message sent by a target base station through a core network device, the method for handing over a cell sends a handover command to a UE, and sends first data to the target base station through an MEC server, where the handover command is used to instruct the UE to handover from a source cell to the target cell, the first data is user data that the core network device has sent to the source base station and the source base station has not sent to the UE, that is, after instructing the UE to handover from the source cell to the target cell, the user data that the core network device has sent to the source base station and the source base station has not sent to the UE is sent to the target base station through the MEC server, compared with the cell handover process in the prior art, the method for switching the cell provided by the embodiment of the invention forwards the user data through the MEC server, so that the user data can be prevented from going to and going to the core network in the process of forwarding the user data, and the sending efficiency of the user data can be improved.

The technical scheme provided by the invention can be applied to various communication systems, such as a 5G communication system, a future evolution system or a plurality of communication convergence systems and the like. A variety of application scenarios may be included, for example, scenarios such as Machine to Machine (M2M), D2M, macro and micro Communication, enhanced Mobile Broadband (eMBB), ultra high reliability and ultra Low Latency Communication (urrllc), and mass internet of things Communication (mtc). These scenarios include, but are not limited to: communication between the UE and the UE, communication between the network side device and the network side device, or communication between the network side device and the UE. The embodiment of the invention can be applied to the communication between the network side equipment and the UE in the 5G communication system, or the communication between the UE and the UE, or the communication between the network side equipment and the network side equipment.

Fig. 1 shows a schematic diagram of a possible structure of a communication system according to an embodiment of the present invention. As shown in fig. 1, the communication system mainly includes: a source base station 11, a target base station 12, a source Mobility Management Function (Access and Mobility Management Function, AMF)13, a target AMF 14, a source User Plane Function (UPF) 15, a target UPF 16, a Mobile Edge Computing (MEC) server 17, a Network Exposure Function (NEF) 18, a Policy Control Function (Policy Control Function, PCF)19, and a User Equipment (User Equipment, UE)100, wherein a Radio Access Network (RAN) mainly includes: a source base station 11, a target base station 12, and a UE100, and a core network mainly includes: source AMF 13, target AMF 14, source UPF15, target UPF 16, NEF18, and PCF 19. The source base station 11 and the target base station 12 are connected with the core network through NG interfaces, specifically, the source base station 11 and the target base station 12 are connected with UPF through NG-U interfaces, the source base station 11 and the target base station 12 are connected with AMF through NG-C interfaces, the source AMF 11 is connected with the source UPF15 through N4 interfaces, the target AMF 14 is connected with the target UPF 16 through N4 interfaces, the MEC server 17 is deployed at the side close to the base station 11 and the target base station 12, the core network selects the UPF close to the UE100, data forwarding from the UPF to the MEC is executed, and information interaction is carried out through the NEF and the MEC. Data transmission between core networks and between the core networks and the base station is carried out via the GTP-U data tunneling protocol. The source base station 11 and the target base station 12 belong to the same MEC cluster, and there is no Xn interface between the source base station 11 and the target base station 12.

The source base station 11 and the target base station 12 may be a Transmission and Reception Point (TRP), a relay station, an access Point, or the like. The source Base Station 11 and the target Base Station 12 may be Base Transceiver Stations (BTSs) in a Global System for Mobile communication (GSM) or Code Division Multiple Access (CDMA) network, may also be nbs (nodebs) in a Wideband Code Division Multiple Access (WCDMA), and may also be enbs (enodebs) (evolved nodebs) in LTE. The source base station 11 and the target base station 12 may also be wireless controllers in a Cloud Radio Access Network (CRAN) scenario. Source base station 11 and target base station 12 may also be network side equipment in a 5G communication system or network side equipment in a future evolution network, for example, base station gNG in a 5G communication system.

Core network devices the core network devices may include a control plane device and a user plane device. The control plane device may include a Mobility Management Entity (MME), and the user plane device may include a Serving Gateway (S-GW), a Packet Data Network Gateway (PDN-GW), and the like. The MME may be used for mobility management, session management, network element selection, and user bearer information storage. The S-GW has functions of session management, routing and data forwarding, quality of service control, charging, and storing information, etc. The PDN-GW may be used for Internet Protocol (IP) address allocation, session management, routing, data forwarding, quality of service control, charging, policy and charging enforcement, and the like.

The UE100 may be a wireless UE, which may be a device that provides voice and/or other traffic data connectivity to a user, a handheld device, computing device, or other processing device connected to a wireless modem, a vehicle mounted device, a wearable device, a UE in a future 5G network or a UE in a future evolved PLMN network, etc., as well as a wired UE. A Wireless UE may communicate with one or more core networks via a Radio Access Network (RAN), and may be a Mobile terminal, such as a Mobile phone (or "cellular" phone) and a computer with a Mobile terminal, for example, a portable, pocket, hand-held, computer-included, or vehicle-mounted Mobile device, which exchanges languages and/or data with the RAN, and Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), and the like, and the Wireless terminal may also be a Mobile device, a UE terminal, an Access terminal, a Wireless Communication device, a terminal unit, a Station, a Mobile Station (Mobile Station), or a vehicle-mounted Mobile device, A Remote Station (Remote Station), a Remote Station, a Remote Terminal (Remote Terminal), a Subscriber Unit (Subscriber Unit), a Subscriber Station (Subscriber Station), a User Agent (User Agent), a Terminal device, and the like. As an example, in the embodiment of the present invention, fig. 1 illustrates that the UE is a mobile phone.

The first embodiment,

An embodiment of the present invention provides a method for switching cells, specifically, referring to fig. 2, the method includes the following steps:

s201, the source base station sends a switching request message to the source AMF.

Correspondingly, the source AMF receives a handover request message sent by the source base station.

The handover request message is used to request handover of a UE from a source cell to a target cell, where the source cell is a cell served by the source base station. The handover request message includes: a first mapping relationship; the first mapping relationship is: mapping relation between sequence Number (PDCP SN) of Packet Data Convergence Protocol and sequence Number (GTP-U SN) of General Packet Radio Service tunneling Protocol of User Plane.

Optionally, the mapping relationship between the PDCP SN and the GTP-U SN may be obtained by the active base station through calculation, and is carried in the handover request message in a mapping relationship manner. For example: the GTP-U SN carried by a data packet received from a core network by a source base station is 11, and the PDCP SN when the data packet is sent to UE after being numbered by the PDCP of the source base station is 7, so that the mapping relation between the PDCP SN and the GTP-U SN is as follows: PDCP SN is GTP-U SN-4.

Further, the source base station sending the handover request message to the source AMF may be triggered by the following steps a-d:

a. a source base station sends configuration information to a UE, wherein the configuration information comprises: name of at least one measurement parameter.

Correspondingly, the UE receives the configuration information sent by the source base station.

b. And the UE obtains the value of the at least one measurement parameter according to the configuration information measurement.

c. The UE transmits measurement report information to the source base station, wherein the measurement report information comprises the value of the at least one measurement parameter.

d. The source base station determines whether to handover the UE from the source base station to the target base station based on the measurement report and Radio Resource Management (RRM) information.

And if the source base station determines to switch the UE from the source base station to the target base station, sending a switching request message to the source AMF.

S202, the source AMF sends the switching request message to the target AMF.

Correspondingly, the target AMF receives the switching request message sent by the source AMF.

S203, the target AMF sends the switching request message to the target base station.

Correspondingly, the target base station receives the handover request message sent by the target AMF.

The target base station is a base station serving a target cell, that is, the target cell is a cell served by the target base station.

Illustratively, as shown in fig. 1, the target AMF and the target base station are connected through an NG-C interface, so the target AMF can transmit a handover request message to the target base station through the NG-C interface.

The source base station sends the handover request message to the target base station through the core network device, and the target base station receives the handover request message sent by the source base station through the core network device.

S204, the target base station sends a switching confirmation message to the target AMF.

Correspondingly, the target AMF receives a handover confirmation message sent by the target base station.

Wherein the handover confirmation message is used for confirming that the user equipment UE is handed over from the source cell to the target cell.

It should be further noted that, when receiving a handover request message sent by a source base station through core network equipment, a target base station may also determine to refuse to handover the UE from the source base station to the target base station, at this time, the target base station does not send a handover confirmation message to the source base station through the core network equipment, that is, does not send a handover confirmation message to a target AMF, and a cell handover procedure is completed.

S205, the target AMF sends the switching confirmation message to the source AMF.

Correspondingly, the source AMF receives the switching confirmation message sent by the target AMF.

S206, the source AMF sends the switching confirmation message to the source base station.

Correspondingly, the source base station receives the handover confirmation message sent by the source AMF.

Also, as shown in fig. 1, the source AMF is connected to the source base station through the NG-C interface, so that the source AMF can transmit a handover confirmation message to the source base station through the NG-C interface.

And the source base station receives the switching confirmation message sent by the target base station through the core network equipment.

S207, the source base station sends a switching command to the UE.

Correspondingly, the UE receives the handover command sent by the source base station.

Wherein the handover command is used to instruct the UE to handover from the source cell to the target cell.

S208, the UE is separated from the source cell and accesses the target cell.

Further, after the UE detaches from the source cell and synchronizes to the target cell, the source base station may perceive that the UE has detached and the target base station may also perceive that the UE has accessed, so the source base station and the target base station perform the following steps S209 and S213, respectively.

It should be noted that, in the embodiment of the present invention, the sequence of the source base station performing the following step S209 and the target base station performing the following step S213 is not limited, that is, the source base station may perform the step S209 first and then perform the step S213, the target base station may perform the step S213 first and then perform the step S209, and the source base station and the target base station may perform the steps S209 and S213 simultaneously.

S209, the source base station sends the first data to the MEC server.

Correspondingly, the MEC receives first data sent by the source base station.

The first data is user data which is sent to the source base station by the core network equipment and is not sent to the UE by the source base station.

Specifically, the first data may specifically include at least one of the following three types of data:

a type: user data that has been received and PDCP-numbered by the source base station, but has not yet been sent to the UE.

B type: the source base station has received, has not performed PDCP numbering, and has not transmitted user data to the UE.

Class C: the core network has transmitted to the source base station, which is receiving the user data.

S210, the MEC server sends and sends the first data to the target base station.

Correspondingly, the target base station receives the first data sent by the MEC server.

That is, the MEC server receives first data sent by a base station serving a cell accessed by the UE before cell switching, and forwards the first data to a base station serving a cell accessed by the UE after cell switching.

That is, after the UE is instructed to switch from the source cell to the target cell, the source base station sends, to the target base station, the user data that has been sent by the core network device to the source base station and that has not been sent by the source base station to the UE through the MEC server.

S211, the target base station performs PDCP numbering on the data packet which is not subjected to the PDCP numbering in the first data according to the first mapping relation.

As described above, the class B packet and the class C packet in the first data are packets for which PDCP numbering is not performed, so that the target base station performs PDCP numbering on the class B packet and the class C packet in the first data according to the first mapping relationship.

Illustratively, the mapping relationship between the PDCP SN and the GTP-U SN is as follows: and the PDCP SN of the class B and C packets in the first data is 20, 21, 22, …, and the PDCP SNs after PDCP numbering are 16, 17, 18, ….

S212, the target base station sends the first data after PDCP numbering to the UE.

Correspondingly, the UE receives the first data sent by the target base station.

S213, the target base station sends a path switching request message to the target AMF.

Correspondingly, the target AMF receives the path switching request message sent by the target base station.

The handover confirmation message is used to confirm that the user equipment UE is handed over from a source cell to a target cell, where the source cell is a cell served by the source base station.

S214, the target AMF controls the target UPF to send the second data to the target base station according to the path switching request message.

Correspondingly, the target base station receives the second data sent by the target UPF.

S215, the target base station carries out PDCP numbering on the second data according to the first mapping relation.

S216, the target base station sends the second data after PDCP numbering to the UE.

Correspondingly, the UE receives the second data sent by the target base station.

Because the source base station carries the mapping relation between the PDCP SN and the GTP-U SN in the switching request message sent by the core network equipment, the target base station can directly carry out the PDCP numbering on the received second data after receiving the second data sent by the target UPF without waiting for the first data to finish transmission, and therefore, the embodiment of the invention can further improve the sending efficiency of the user data by carrying the mapping relation between the PDCP SN and the GTP-U SN in the switching request message.

Further, after the step flow shown in fig. 2, the method for switching cells provided in the embodiment of the present invention may further include the following steps 1 to 4.

1. And the target base station sends a switching completion notice to the target AMF.

Correspondingly, the target AMF receives the switching completion notice sent by the target base station.

Wherein the handover complete notification is used to indicate that cell handover is complete.

2. The target AMF sends the handover completion notification to the source AMF.

Correspondingly, the source AMF receives and receives the switching completion notification sent by the target AMF.

3. And the source AMF receives and sends the switching completion notice to the source base station.

Correspondingly, the source base station receives the switching completion notification sent by the source AMF.

4. The source base station releases the context of the UE.

Further, the data distribution process of the conventional network is as follows: the data is sent to the core network via the mobile internet, the core network forwards the data to the base station, and then the base station sends the data to the user. Due to the rapid development of the mobile internet and the internet of things and the continuous emergence of various novel services, the mobile data traffic will show explosive growth, and if the data traffic is processed by the core network and the remote cloud data center, the service carrying capacity of the core network is inevitably too large, so that the time delay is increased suddenly, the service congestion is caused, and the network performance and the user experience are greatly influenced. In order to solve the above problem, referring to fig. 3, the method for switching cells according to an embodiment of the present invention further includes the following steps:

s301, the MEC server judges whether second data are cached.

Optionally, the method for the MEC server to cache the data may be as follows: after the MEC server is connected with the base stations, the MEC server and the base stations form a network cluster, the MEC server is a cluster head of the network cluster, the base stations connected to the same MEC server belong to the same cluster, and share an MEC ID. Before cell switching, UE accessed by a base station in a network cluster reports self state information to a service base station periodically, and the base station forwards the self state information and the UE state information to an MEC server, so that the MEC server grasps global information in the cluster. The MEC server can cache the hot content of the in-cluster network from the Internet, sort and set the heat value, and dynamically update the cache content according to the heat value.

Specifically, the source base station sends the first data to the MEC server, and may simultaneously notify the MEC server of the status information of the data service currently performed by the UE. After receiving the state information of the current data service of the UE, the MEC server analyzes the data packet in the first data, and can obtain the service data packet to be sent to the UE next, that is, obtain the second data to be sent to the UE next.

In the above step S301, if the MEC server caches the second data, the step S302 is performed, and if the MEC server does not cache the second data, the step S303 is performed.

S302, the MEC server sends a first request message to the target base station.

Correspondingly, the target base station receives the first notification message sent by the MEC server.

Wherein the first request message is used for requesting to send the second data to the target base station.

S303, the MEC server judges whether the second data is stored in a local network.

Specifically, the MEC server is configured to perform a local network Protocol (IP) address query function. For example, when the UE accesses the local network through Uniform Resource Locator (URL) "www.LocalInternet.com", the MEC server is triggered to perform an inquiry to inquire whether the IP address of the server corresponding to www.LocalInternet.com belongs to the local network.

In the above step S303, if the MEC server determines that the second data is stored in the local network, the step S302 is executed, and if the MEC server determines that the second data is not stored in the local network, the step S304 is executed.

S304, the MEC server judges whether to communicate with the first server.

Wherein the first server is a server storing the second data.

It should be noted that the first server may specifically be a server that stores the service data requested by the UE, that is, the first server stores both the first data and the second data.

Specifically, in the MEC specification of the European Telecommunications Standardization Institute (ETSI), the MEC server may be opened to third-party developers to provide third-party application integration. For example, an enterprise may deploy a dedicated MEC server, and enterprise authenticated user data services may directly access the enterprise network through the MEC server without going through the core network, so the MEC server may directly communicate with some servers.

In the above step S304, if the MEC server is communicated with the first server, step S302 is executed, and if the MEC server is not communicated with the first server, the flow of the step of the scheme is ended.

When the target base station receives the first request message sent by the MEC server, whether to receive the second data sent by the MEC server is judged based on the current network environment, if the second data sent by the MEC server is not received, the scheme flow is ended, and if the second data sent by the MEC server is received, the following steps S305-S307 are executed.

S305, the target base station sends a first response message to the MEC server.

Correspondingly, the MEC server receives a first response message sent by the target base station.

Wherein the first reply message is used to confirm to receive the second data sent by the MEC server.

S306, the target base station sends a first notification message to the core network equipment.

Correspondingly, the core network device receives a first notification message sent by the target base station.

Wherein the first notification message is used to instruct the core network device to stop sending the second data to the target base station.

S307, the target base station discards the data packet which is subjected to the packet data convergence protocol PDCP numbering in the second data.

After the MEC server receives the first response message sent by the target base station, the following step S308 is executed.

S308, the MEC server sends the second data to the target base station.

Correspondingly, the target base station receives the second data sent by the MEC server.

When the target AMF in the core network device receives the first notification message sent by the target base station, the following step S309 is performed.

S309, the target AMF controls the target UPF to stop sending the second data to the target base station according to the first notification message.

S310, the target base station carries out PDCP numbering on the second data sent by the MEC server.

S311, the target base station sends the second data after PDCP numbering to the UE.

Correspondingly, the UE receives second data sent by the target base station.

In the embodiment, under the condition that the MEC server caches the second data, or the second data is stored in the local network, or the MEC server is communicated with the first server, the second data is directly sent to the target base station through the MEC server, so that the data flow is prevented from being processed by the core network and the remote cloud data center, and the problems of sudden increase of time delay, service congestion and the like caused by overlarge service carrying capacity of the core network can be solved.

Example II,

Referring to fig. 4, a base station 400 according to an embodiment of the present invention includes:

a receiving unit 41, configured to receive a handover confirmation message sent by a target base station through a core network device, where the handover confirmation message is used to confirm that a user equipment UE is handed over from a cell served by the base station to a target cell;

a sending unit 42, configured to send a handover command to the UE, and send first data to the target base station through a mobile edge computing MEC server, where the handover command is used to instruct the UE to handover from a cell served by the base station to the target cell, the target cell is a cell served by the target base station, and the first data is user data that has been sent to the source base station by the core network device and is not sent to the UE by the source base station.

Optionally, the sending unit 42 is further configured to send, through the core network device, a handover request message to the target base station, where the handover request message is used to request to handover the UE from a cell served by the base station to the target cell, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

The base station provided in the embodiment of the present invention sends a handover command to the UE after receiving a handover confirmation message sent by a target base station through a core network device, and sends first data to the target base station through an MEC server, where the handover command is used to instruct the UE to handover from the source cell to the target cell, the first data is user data that the core network device has sent to the source base station and the source base station has not sent to the UE, that is, after instructing the UE to handover from the source cell to the target cell, the user data that the core network device has sent to the base station and the base station has not sent to the UE is sent to the target base station through the MEC server, and compared with the prior art in which user data forwarding needs to go to and fro the core network during a cell handover process, the base station provided in the embodiment of the present invention forwards the user data through the MEC server, therefore, the user data can be prevented from going to and fro the core network in the process of forwarding, and the sending efficiency of the user data can be improved.

Example III,

An embodiment of the present invention provides an MEC server, and specifically, as shown in fig. 5, the MEC server includes:

a receiving unit 51, configured to receive first data sent by a source base station, where the first data is user data that has been sent to the source base station by a core network device and is not sent to a user equipment UE by the source base station;

a sending unit 52, configured to send and send the first data to the target base station;

the source base station is a base station serving a cell accessed by the UE before cell switching, the target base station is a base station serving a cell accessed by the UE after cell switching, and the first data is user data which is sent to the source base station by the core network equipment and is not sent to the UE by the source base station.

Optionally, the sending unit 52 is further configured to send a first request message to the target base station when it is determined that the second data is cached; the first request message is used for requesting to send the second data to the target base station, and the second data is user data which is not sent to the source base station by core network equipment.

Optionally, the sending unit 52 is further configured to send the first request message to the target base station when it is determined that the second data is not cached in the local network.

Optionally, in a case that it is confirmed that the second data is not stored in the local network, the sending unit 52 is further configured to send the first request message to the target base station in a case that it is confirmed that the second data is communicated with the first server;

the first server is a server storing the second data.

Optionally, the receiving unit 51 is further configured to receive a first response message sent by the target base station, where the first response message is used to confirm to receive the second data sent by the MEC server;

the sending unit 52 is further configured to send the second data to the target base station.

The MEC server provided by the embodiment of the present invention sends and sends the first data to the target base station after receiving the first data sent by the source base station, that is, in the cell handover process in the embodiment of the present invention, the MEC server sends the user data, which has been sent to the source base station by the core network device and is not sent to the UE by the source base station, to the target base station.

Example four,

An embodiment of the present invention provides a base station, and specifically, as shown in fig. 6, the base station 600 includes:

a sending unit 61, configured to send a handover confirmation message to the source base station through the core network device;

a receiving unit 62, configured to receive first data sent by the source base station through the mobile edge computing MEC server;

the handover confirmation message is used to confirm that a User Equipment (UE) is handed over from a source cell to a cell served by the base station, where the first data of the cell served by the source cell is user data that has been sent to the source base station by the core network device and has not been sent to the UE by the source base station.

Optionally, the sending unit 61 is further configured to send a path switching request message to the core network device;

the receiving unit 62 is further configured to receive second data sent by the core network device;

the path switching request message is used for requesting the core network device to send second data to the base station, where the second data is user data that is not sent to the source base station by the core network device.

Optionally, the receiving unit 62 is further configured to receive a handover request message sent by the source base station through the core network device, where the handover request message is used to request to handover user equipment UE to the target base station, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

Optionally, the base station 600 further includes: a numbering unit 63;

the numbering unit 63 is configured to perform PDCP numbering on the data packet that is not subjected to the PDCP numbering in the first data and the second data according to the first mapping relationship.

Optionally, the receiving unit 62 is further configured to receive a first request message sent by the MEC server, where the first request message is used to request to send the second data to the target base station;

the sending unit 61 is further configured to receive a first request message sent by the MEC server, where the first request message is used to request to send the second data to the target base station; the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

the numbering unit 63 is further configured to discard a data packet, which is numbered by a packet data convergence protocol PDCP in the second data;

the receiving unit 62 is further configured to receive the second data sent by the MEC server.

The base station provided by the embodiment of the invention receives the first data sent by the source base station through the mobile edge computing MEC server after sending the switching confirmation message to the source base station through the core network device, namely, in the cell switching process in the embodiment of the invention, the user data which is sent to the source base station by the core network device and is not sent to the UE by the source base station is received through the MEC server.

Example V,

An embodiment of the present invention provides an AMF, and specifically, referring to fig. 7, the AMF 700 includes:

a receiving unit 71, configured to receive a handover request message sent by a source base station, where the handover request message is used to request that a user equipment UE is handed over from a source cell to a target cell;

a sending unit 72, configured to send the handover request message to the target base station through a target AMF;

the receiving unit 71 is further configured to receive a handover confirmation message sent by the target base station through the target AMF; the handover confirmation message is used to confirm handover of the UE from the source cell to the target cell;

the sending unit 72 is further configured to send the handover confirmation message to the source base station;

Because the source base station carries the mapping relation between the PDCP SN and the GTP-U SN in the switching request message sent to the target base station by the AMF, the target base station can directly carry out the PDCP numbering on the received second data after receiving the second data sent by the target UPF without waiting for the first data to finish transmission, and therefore, the embodiment of the invention can improve the sending efficiency of the user data by carrying the mapping relation between the PDCP SN and the GTP-U SN in the switching request message.

Example six,

An embodiment of the present invention provides an AMF, and specifically, referring to fig. 8, the AMF 800 includes:

a receiving unit 81, configured to receive a handover request message sent by a source base station through a source AMF, where the handover request message is used to request that a user equipment UE be handed over from a source cell to a target cell;

a sending unit 82, configured to send the handover request message to the target base station;

the receiving unit is further configured to receive a handover confirmation message sent by the target base station, where the handover confirmation message is used to confirm that the UE is handed over from the source cell to the target cell;

the sending unit 82 is further configured to send the handover confirmation message to the source base station through the source AMF;

Optionally, referring to fig. 8, the AMF further includes: a processing unit 83;

the receiving unit 81 is further configured to receive a path switching request message sent by the target base station;

the processing unit 83 is configured to control a target user plane function UPF to send the second data to the target base station according to the path switching request message;

the path switching request message is used for requesting the core network device to send second data to the target base station, where the second data is user data that is not sent to the source base station by the core network device.

Optionally, the receiving unit 81 is further configured to use a first notification message sent by the target base station, where the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

the processing unit 83 is further configured to control the target UPF to stop sending the second data to the target base station according to the first notification message.

Example seven,

An embodiment of the present invention further provides a base station, and as shown in fig. 9, the base station includes: the processor 91, the memory 92, and a computer program stored in the memory 92 and capable of running on the processor 91, where the computer program, when executed by the processor 91, implements the steps executed by the source base station and/or the target base station in the method for switching cells in the first embodiment, and can achieve the same technical effects, and are not described herein again to avoid repetition.

An embodiment of the present invention further provides an MEC server, and as shown in fig. 10, the MEC server includes: the processor 101, the memory 102, and a computer program stored in the memory 102 and capable of running on the processor 101, where the computer program, when executed by the processor 101, implements the steps executed by the MEC server in the method for switching cells in the first embodiment, and can achieve the same technical effects, and are not described herein again to avoid repetition.

An embodiment of the present invention further provides an AMF, as shown in fig. 11, where the AMF includes: the processor 111, the memory 112, and a computer program stored in the memory 112 and capable of running on the processor 111, where the computer program, when executed by the processor 111, implements the steps executed by the source AMF and/or the target AMF in the method for cell handover in the first embodiment, and can achieve the same technical effects, and are not described herein again to avoid repetition.

An embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements multiple processes of the method for cell handover in the foregoing embodiments, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here. The computer-readable storage medium may be a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk.

An embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements multiple processes of the above method for switching cells, and can achieve the same technical effect, and in order to avoid repetition, details are not repeated here. The computer readable storage medium is, for example, ROM, RAM, magnetic disk or optical disk.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. 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 (e.g., ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal (e.g., a mobile phone, a computer, a server, an air conditioner, or a network-side device) to execute the method for switching cells according to the embodiments of the present invention.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for handing over a cell, for a source base station, the method comprising:

2. The method of claim 1, wherein before receiving the handover confirmation message sent by the target base station through the core network device, the method further comprises:

sending a handover request message to the target base station through the core network device, where the handover request message is used to request handover of the UE from the source cell to the target cell, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

3. A method for cell handover, applied to a mobile edge computing, MEC, server, the method comprising:

transmitting the first data to a target base station;

4. The method of claim 3, further comprising:

under the condition that the second data are confirmed to be cached, sending a first request message to the target base station; the first request message is used for requesting to send the second data to the target base station, and the second data is user data which is not sent to the source base station by core network equipment.

5. The method of claim 4, wherein in the event that the second data is acknowledged as not cached, the method further comprises:

and sending the first request message to the target base station under the condition of confirming that the second data is stored in the local network.

6. The method of claim 5, wherein in the event that the second data is not stored in the local network, the method further comprises:

under the condition of confirming communication with a first server, sending a first request message to the target base station;

the first server is a server storing the second data.

7. The method of any of claims 4-6, wherein after sending the first request message to the target base station, the method further comprises:

receiving a first response message sent by the target base station, wherein the first response message is used for confirming to receive the second data sent by the MEC server;

and sending the second data to the target base station.

8. A method for switching cells, applied to a target base station, the method comprising:

9. The method of claim 8, further comprising:

sending a path switching request message to the core network equipment;

receiving second data sent by the core network equipment;

10. The method of claim 9, wherein before sending the handover confirm message to the source base station through the core network device, the method further comprises:

receiving a handover request message sent by the source base station through the core network device, where the handover request message is used to request to handover User Equipment (UE) to the target base station, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

11. The method of claim 10, further comprising:

and carrying out PDCP numbering on the data packet which is not subjected to the PDCP numbering in the first data and the second data according to the first mapping relation.

12. The method of claim 11, further comprising:

receiving a first request message sent by the MEC server, wherein the first request message is used for requesting to send the second data to the target base station;

sending a first response message to the MEC server, sending a first notification message to the core network device, and discarding a data packet with a packet data convergence protocol PDCP number in the second data, where the first response message is used to confirm to receive the second data sent by the MEC server, and the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

receiving the second data sent by the MEC server.

13. A method for switching cells, applied to a source mobility management function (AMF), the method comprising:

sending the handover confirmation message to the source base station;

14. A method for switching cells, which is applied to a target mobility management function (AMF), and comprises:

sending the handover request message to the target base station;

sending the handover confirmation message to the source base station through the source AMF;

15. The method of claim 14, further comprising:

receiving a path switching request message sent by the target base station;

controlling a target User Plane Function (UPF) to send second data to the target base station according to the path switching request message;

the path switching request message is used for requesting core network equipment to send the second data to the target base station, and the second data is user data which is not sent to the source base station by the core network equipment.

16. The method of claim 15, further comprising:

receiving a first notification message sent by the target base station, where the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

and controlling the target UPF to stop sending the second data to the target base station according to the first notification message.

17. A base station, comprising:

a sending unit, configured to send a handover command to the UE, and send first data to the target base station through a mobile edge computing MEC server, where the handover command is used to instruct the UE to handover from a cell served by the base station to the target cell, the target cell is a cell served by the target base station, and the first data is user data that has been sent to a source base station by the core network device and is not sent to the UE by the source base station.

18. The base station of claim 17, wherein the sending unit is further configured to send, by the core network device, a handover request message to the target base station, where the handover request message is used to request handover of the UE from a cell served by the base station to the target cell, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

19. A mobile edge computing, MEC, server, comprising:

a receiving unit, configured to receive first data sent by a source base station, where the first data is user data that has been sent to the source base station by a core network device and is not sent to a user equipment UE by the source base station;

a sending unit, configured to send the first data to a target base station;

20. The MEC server of claim 19, wherein the sending unit is further configured to send a first request message to the target base station when it is determined that second data is cached, where the first request message is used to request that the second data is sent to the target base station, and the second data is user data that is not sent to the source base station by a core network device.

21. The MEC server of claim 20, wherein the sending unit, in case it is confirmed that the second data is not cached, is further configured to send the first request message to the target base station in case it is confirmed that the second data is stored in a local network.

22. The MEC server of claim 21, wherein the sending unit is further configured to send the first request message to the target base station if it is confirmed that the second data is not stored in the local network and if it is confirmed that the second data is communicated with the first server;

the first server is a server storing the second data.

23. The MEC server of any one of claims 20-22,

the receiving unit is further configured to receive a first response message sent by the target base station, where the first response message is used to confirm to receive the second data sent by the MEC server;

the sending unit is further configured to send the second data to the target base station.

24. A base station, comprising:

25. The base station of claim 24,

the sending unit is further configured to send a path switching request message to the core network device;

the receiving unit is further configured to receive second data sent by the core network device;

26. The base station of claim 25, wherein the receiving unit is further configured to receive a handover request message sent by the source base station through the core network device, where the handover request message is used to request a handover of a UE to a target base station, and the handover request message includes: a first mapping relationship, the first mapping relationship being: and mapping relation between the sequence number PDCP SN of the packet data convergence protocol and the sequence number GTP-U SN of the user plane general packet radio service tunneling protocol.

27. The base station of claim 26, wherein the base station further comprises: a numbering unit;

the numbering unit is configured to perform PDCP numbering on the data packet that is not subjected to the PDCP numbering in the first data and the second data according to the first mapping relationship.

28. The base station of claim 27,

the receiving unit is further configured to receive a first request message sent by the MEC server, where the first request message is used to request to send the second data to the target base station;

the sending unit is further configured to send a first response message to the MEC server, and send a first notification message to the core network device, where the first response message is used to confirm to receive the second data sent by the MEC server, and the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

the numbering unit is further configured to discard a data packet, which is numbered by a packet data convergence protocol PDCP in the second data;

the receiving unit is further configured to receive the second data sent by the MEC server.

29. A mobility management function, AMF, comprising:

30. A mobility management function, AMF, comprising:

a receiving unit, configured to receive a handover request message sent by a source base station through a source AMF, where the handover request message is used to request to handover a user equipment UE from a source cell to a target cell;

a sending unit, configured to send the handover request message to the target base station;

the sending unit is further configured to send the handover confirmation message to the source base station through the source AMF;

31. The AMF of claim 30, further comprising: a processing unit;

the receiving unit is further configured to receive a path switching request message sent by the target base station;

the processing unit is configured to control a target user plane function UPF to send second data to the target base station according to the path switching request message;

the path switching request message is used for requesting core network equipment to send second data to the target base station, where the second data is user data that is not sent to the source base station by the core network equipment.

32. The AMF of claim 31,

the receiving unit is further configured to receive a first notification message sent by the target base station, where the first notification message is used to instruct the core network device to stop sending the second data to the target base station;

the processing unit is further configured to control the target UPF to stop sending the second data to the target base station according to the first notification message.

33. A base station, comprising: processor, memory and computer program stored on the memory and executable on the processor, which computer program, when executed by the processor, performs the steps of the method of handing over a cell of any of claims 1, 2, 8-12.

34. A mobile edge computing, MEC, server, comprising: processor, memory and computer program stored on the memory and executable on the processor, which computer program, when being executed by the processor, carries out the steps of the method of handing over a cell according to any of the claims 3-7.

35. A mobility management function, AMF, comprising: processor, memory and computer program stored on the memory and executable on the processor, which computer program, when being executed by the processor, carries out the steps of the method of handing over a cell according to any of the claims 13-16.

36. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method of handing over a cell according to any one of claims 1-16.