CN108632922B

CN108632922B - Mobility management method and device

Info

Publication number: CN108632922B
Application number: CN201710179843.6A
Authority: CN
Inventors: 戴谦
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2017-03-23
Filing date: 2017-03-23
Publication date: 2022-07-19
Anticipated expiration: 2037-03-23
Also published as: WO2018171463A1; CN108632922A

Abstract

Disclosed herein are a mobility management method and apparatus, the method including: determining a cell change mode of the UE after the UE in an inactive state or a light-connected state meets the cell change condition and a target base station of a cell change is determined; executing the switching of the UE according to the determined cell switching mode; the cell changing mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; and transferring the user plane link of the UE to a target base station. According to the method and the device, mobility management between LTE and 5G New RAT in an inactive state or a light connected state is realized.

Description

Mobility management method and device

Technical Field

The present invention relates to the field of communications, and in particular, to a mobility management method and apparatus.

Background

In the Long Term Evolution (LTE) standard and the 5G new Radio Access Network (RAN) standard discussed in the current third Generation Partnership Project (3 GPP), a light connected (light connected) state is introduced in LTE, and an inactive (inactive) state is introduced in 5G new RAT, which are similar in nature, for LTE RAN and 5G RAN, respectively, both the light connected state and the inactive state belong to sub-states of a Radio Resource Control (RRC) connected state, and if the terminal is in the light connected state or the inactive state, the RRC connection with the RAN is still maintained, and the signaling bearer and the data bearer are still maintained, but the difference from the RRC connected state is that: the terminal and the RAN need to store the context of the terminal, the mobility of the terminal adopts a cell reselection mode, and the terminal monitors paging of the RAN and a Core Network (CN). The introduction of the 2 new states can partially reduce the power consumption of the terminal and the switching times of the terminal from an IDLE (IDLE) state to a connected state, thereby reducing part of signaling overhead.

The introduction of new states in LTE and 5G new RATs raises new issues. Since the handover between networks in the related art does not involve new states in LTE and 5G new RAT, it cannot be applied in this scenario. For the problem of mobility management between LTE and 5G base stations in the new RRC state of LTE and 5G, no effective solution has been proposed in the related art.

Disclosure of Invention

In order to solve the above technical problem, embodiments of the present invention provide a mobility management method and apparatus.

The present application provides:

a mobility management method, comprising:

determining a cell change mode of the UE after the UE in an inactive state or a light-connected state meets the cell change condition and a target base station of a cell change is determined;

executing the switching of the UE according to the determined cell switching mode;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

Wherein the target base station satisfies one of:

the RAT of the wireless access technology is the same as the source base station;

the radio access technology RAT to which it belongs is not of the same class as the source base station.

Wherein the performing the handover of the UE according to the determined cell change mode comprises:

and sending a cell change request message to the target base station, wherein the cell change request message carries the cell change mode identifier, and the cell change mode identifier is used for identifying the determined cell change mode.

Wherein, sending a cell change request message to the target base station, the cell change request message further includes: and the source base station allocates an access stratum context identifier (AS context ID) of the UE, wherein the AS context identifier is used for identifying the identity of the UE at the source base station and storing the context of the UE at the source base station.

receiving a change cell response message from a target base station, the change cell response message carrying one or more of the following: the UE ID or AS context ID allocated to the UE by the target base station and the context established for the UE by the target base station side; and sending a cell change command message to the UE, wherein the cell change command message is used for indicating the UE to initiate a cell change to the target base station, and the cell change command message at least comprises a UE ID or an AS context ID which is distributed to the UE by the target base station.

When the cell change mode is to keep the user plane link of the UE to the source base station, sending a cell change command message to the UE, where the cell change command message is further used to instruct the UE to stop one or more of the following behaviors:

stopping the periodic monitoring of the physical channel of the source base station after the process of changing the cell is finished;

stopping a RAN area notification update (RAN area notification update);

the measurement to the source base station is stopped.

Wherein, executing the handover of the UE according to the determined cell change mode comprises:

and when the cell changing mode is to keep the user plane of the UE linked to the source base station, reserving functional entities corresponding to a PDCP layer, an RLC layer and an RRC layer of the UE at the source base station, and processing user plane data and control plane signaling which are transmitted to the source base station by the target base station so that the target base station only completes MAC layer operation of the data and the signaling which are received and transmitted by the UE.

and when the cell changing mode is to keep the user plane of the UE linked to the source base station, sending a cell changing request message to the target base station, wherein the cell changing request message carries parts related to MAC scheduling, measurement, system messages and a physical layer in the UE context of the source base station, and does not contain context parts related to PDCP, RLC and safety.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and when the cell changing mode is to keep the user plane of the UE linked to the source base station, keeping the UE in an inactive state and storing the context of the UE.

Wherein the performing handover of the UE according to the determined cell change manner includes one or two of: when the cell changing mode is to keep the user plane link of the UE at a source base station, receiving a notification message from a target base station, wherein the notification message is used for informing the source base station that the UE has accessed at the target base station; and after the UE is known to be accessed in the target base station, sending updated AS security information or NAS security information to the UE to the target base station.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and when the cell changing mode is to transfer the user plane link of the UE to a target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, and the suspension instruction is used for indicating the UE to save the context of the source base station after the cell changing is finished, and besides sending the cell changing command message to the UE, saving the context of the source base station side of the UE.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: when the cell change mode is to transfer the user plane link of the UE to the target base station, sending a cell change command message to the UE, wherein the cell change command message further comprises: and the target base station side establishes context, AS security information or NAS security information for the UE.

A mobility management apparatus comprising:

a first determining module, configured to determine a cell change mode of the UE when the inactive state or the light-connected state of the UE satisfies a cell change condition and a target base station of a cell change is determined;

a first switching module, configured to perform switching of the UE according to the determined cell change manner;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes:

sending a cell change request message to the target base station, wherein the cell change request message comprises: and the source base station allocates an access stratum context identifier (AS context ID) of the UE, wherein the AS context identifier is used for identifying the identity of the UE at the source base station and storing the context of the UE at the source base station.

receiving a change cell response message from a target base station, the change cell response message carrying one or more of the following: the UE ID or AS context ID allocated to the UE by the target base station and the context established for the UE by the target base station side;

sending a cell change command message to the UE, wherein the cell change command message is used for indicating the UE to initiate a cell change to the target base station, and the cell change command message at least comprises a UE ID or an AS context ID allocated to the UE by the target base station.

stop a RAN area update (RAN area notification update);

the measurement to the source base station is stopped.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane of the UE linked to the source base station, reserving functional entities corresponding to a PDCP layer, an RLC layer and an RRC layer of the UE at the source base station, and processing user plane data and control plane signaling which are transmitted to the source base station by the target base station so that the target base station only completes MAC layer operation of the data and the signaling which are received and transmitted by the UE.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane of the UE linked to the source base station, keeping the UE in an inactive state and storing the context of the UE.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving a notification message from the target base station and returning a response message to the target base station, wherein the notification message is used for notifying the source base station that the UE is accessed at the target base station, and the response message carries updated AS security information or NAS security information for the UE.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to transfer the user plane link of the UE to the target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, and the suspension instruction is used for indicating the UE to save the source base station context after finishing changing the cell, and saving the source base station side context of the UE after sending the cell changing command message to the UE.

Wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes: when the cell change mode is to transfer the user plane link of the UE to the target base station, sending a cell change command message to the UE, wherein the cell change command message further comprises: and the target base station side establishes context, AS security information or NAS security information for the UE.

A mobility management method, comprising:

receiving a cell change request message from a source base station, wherein the cell change request message at least carries a cell change mode identifier which indicates a cell change mode determined by the source base station;

executing the switching of the UE according to the cell switching mode indicated by the cell switching request message;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes:

and when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving updated AS security information or NAS security information from the source base station to the UE, and transmitting the updated AS security information or NAS security information to the UE.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: and when the cell changing mode is to transfer the user plane link of the UE to a target base station, and when the source base station and the target base station share the same core network node, sending a cell changing response message to the source base station, wherein the cell changing response message comprises AS security information established by the target base station for the UE and an NAS security information holding identifier, and the NAS security information holding identifier is used for informing the UE of holding the NAS security information of the source cell for reuse in the target base station after the cell changing is completed.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: when the cell changing mode is to transfer the user plane link of the UE to the target base station, when receiving an AS security completion message of the UE transparently transmitted by the source base station, confirming that AS security negotiation is completed; and when receiving the NAS security completion message of the UE transparently transmitted by the source base station, forwarding the NAS security completion message to a core network to complete the negotiation confirmation of NAS security.

A mobility management apparatus comprising:

A second receiving module, configured to receive a cell change request message from a source base station, where the cell change request message at least carries a cell change mode identifier, and the cell change mode identifier indicates a cell change mode determined by the source base station;

a second switching module, configured to execute a switching of the UE according to a cell change mode indicated by the cell change request message;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

The second handover module is configured to execute handover of the UE according to the cell change mode indicated by the cell change request message, and includes:

and when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving a response message from the source base station, wherein the response message carries updated AS security information or NAS security information, and transmitting the updated AS security information or NAS security information to the UE.

And when the cell changing mode is to transfer the user plane link of the UE to a target base station, and when the source base station and the target base station share the same core network node, sending a cell changing response message to the source base station, wherein the cell changing response message comprises AS security information established by the target base station for the UE, no NAS security information and an identifier, and the identifier is used for informing the UE that the NAS security information of the source cell is reserved after the cell changing is completed so AS to be reused in the target base station.

Wherein, the second handover module is configured to execute handover of the UE according to the cell change mode indicated by the cell change request message, and includes: when the cell changing mode is to transfer the user plane link of the UE to a target base station, when receiving an AS safety completion message of the UE transparently transmitted by the source base station, confirming that AS safety negotiation is completed; and when receiving the NAS security completion message of the UE transparently transmitted by the source base station, forwarding the NAS security completion message to a core network to complete the negotiation confirmation of NAS security.

A mobility management method, comprising:

receiving a cell change command message issued by a source base station, wherein the cell change command message is used for instructing UE to initiate cell change to a target base station, and the cell change command message at least carries a cell change mode identifier determined by the source base station;

Executing switching according to the cell switching mode indicated by the cell switching command message;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

Wherein, according to the cell changing mode indicated by the cell changing command message, executing switching comprises:

acquiring a UE ID or an AS context ID distributed to the UE by the target base station from the command message for changing the cell;

and initiating access to a target base station, and reporting the UE ID or AS context ID allocated to the UE by the target base station to the target base station in the access process.

Wherein, according to the cell changing mode indicated by the cell changing command message, executing the switching comprises:

and the cell changing mode is to keep the state of the user interface of the UE in the source base station and save the context of the user interface in the source base station when the user interface of the UE is linked to the source base station.

Wherein the state of keeping itself at the source base station comprises: keeping the PDCP entity and the PDCP state, the RLC entity and the RLC state, the AS security information and the NAS security information of the base station in the source base station, and transferring the state of the base station to an IDLE state.

When the cell changing mode is to transfer the user plane link of the UE to a target base station, transferring the state of the UE in a source base station to an IDLE state after finishing the switching process;

the cell changing mode is that when the user plane of the UE is kept linked to the source base station, the behavior of the corresponding item is stopped according to the cell changing command message;

wherein the behavior of the corresponding item comprises one or more of:

stopping periodic listening of a physical channel to a source base station;

stopping RAN area update;

the measurement to the source base station is stopped.

and the cell changing mode is that when the user plane of the UE is kept to be linked with a source base station, after the target base station is accessed, the PDCP entity, the RLC entity, the AS security information and the NAS security information of the source base station which are kept by the user plane are used for processing the operations of the PDCP layer and the RLC layer, the AS encryption and decryption, the NAS encryption and decryption and the integrity protection when receiving and sending data or signaling.

And the cell changing mode is that when the user plane of the UE is kept linked to a source base station, after the target base station is accessed, if AS security information or NAS security information from the source base station and transmitted by the target base station is updated, the updated AS security information or NAS security information is adopted to complete AS encryption and decryption, NAS encryption and decryption and integrity protection of data or signaling.

Wherein, executing the switch according to the cell changing mode indicated by the cell changing command message comprises:

when the cell changing mode is to transfer the user plane link of the UE to the target base station:

if the received command message for changing the cell carries the context of the target base station side established by the target base station for the UE, acquiring the context of the target base station side from the command message for changing the cell and storing the context;

if the received cell change command message carries AS security information generated by the target base station for the UE, completing AS security key negotiation according to the AS security information, and sending an AS security completion message to the target base station through the source base station when the key negotiation is successful;

and if the received command message for changing the cell carries NAS security information generated by a core network connected with the target base station, completing NAS security key negotiation according to the NAS security information, and transmitting the NAS security completion message to the core network connected with the target base station through the source base station when the key negotiation is successful.

A mobility management apparatus comprising:

a third receiving module, configured to receive a cell change command message issued by a source base station, where the cell change command message is used to instruct a UE to initiate a cell change to a target base station, and the cell change command message at least carries a cell change mode identifier determined by the source base station;

a third switching module, configured to execute switching according to the cell change mode indicated by the cell change command message;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

Wherein, the third handover module is configured to execute handover according to the cell change mode indicated by the cell change command message, and includes:

The cell changing mode is that when the user plane of the UE is linked to the source base station, the state of the UE in the source base station is kept, and the context of the UE in the source base station is stored;

wherein the state of keeping itself at the source base station comprises: keeping the PDCP entity and the PDCP state, the RLC entity and the RLC state, the AS security information and the NAS security information of the base station at the source base station, and transferring the state of the base station to the IDLE state.

wherein the behavior of the corresponding item comprises one or more of:

stopping periodic listening of a physical channel to a source base station; stopping RAN area update;

the measurement to the source base station is stopped.

and the cell changing mode is that when the user plane of the UE is kept to be linked with a source base station, after the target base station is accessed, the PDCP entity, the RLC entity, the AS security information and the NAS security information of the source base station, which are kept by the UE, are used for processing the operations of the PDCP layer and the RLC layer, the AS encryption and decryption, the NAS encryption and decryption and the integrity protection when receiving and sending data or signaling.

Wherein, the third handover module is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

and the cell changing mode is that when the user plane of the UE is kept linked to a source base station, after the AS security information or the NAS security information from the source base station which is transmitted by the target base station in a transparent way is updated, the AS encryption and decryption, the NAS encryption and decryption and integrity protection of data or signaling are completed by adopting the updated AS security information or the NAS security information.

when the command message for changing the cell carries the context of the target base station side established by the target base station for the UE, acquiring and storing the context of the target base station side from the command message for changing the cell;

when the command message for changing the cell carries AS security information, completing AS security key negotiation according to the AS security information, and when the key negotiation is successful, sending an AS security completion message to a target base station through a source base station;

And when the NAS security information is carried in the command message for changing the cell, completing NAS security key negotiation according to the NAS security information, and transmitting the NAS security completion message to a core network connected with the target base station through the source base station when the key negotiation is successful.

Wherein, the third handover module is configured to execute handover according to the cell change mode indicated by the cell change command message, and includes: and the cell changing mode is to transfer the state of the UE in the source base station to an IDLE state after the switching is finished when transferring the user plane of the UE to be linked to the target base station.

A mobility management apparatus comprising: a processor and a memory, the memory storing computer-executable instructions that, when executed by the processor, implement a method comprising:

wherein the cell change mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; transferring a user plane link of the UE to a target base station;

Alternatively, the computer executable instructions, when executed by the processor, implement the method of:

the cell change mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; transferring a user plane link of the UE to a target base station;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring the user plane link of the UE to a target base station.

The mobility management method and the mobility management device in the embodiment of the invention realize mobility management between LTE and 5G New RAT in an inactive state or a light connected state, and solve the problem of mobility management between LTE and 5G base stations in an RRC New state of LTE and 5G.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

Fig. 1 is a flowchart illustrating a mobility management method according to an embodiment of the present invention;

fig. 2 is a schematic diagram illustrating a structure of a mobility management apparatus according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating a second mobility management method according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a second mobility management apparatus according to an embodiment of the present invention;

Fig. 5 is a flowchart illustrating a method for mobility management according to a third embodiment of the present invention;

fig. 6 is a schematic structural diagram of a third mobility management device according to an embodiment of the present invention;

fig. 7 is a re-configured cell architecture diagram of example 1;

fig. 8 is a mobility management flow diagram of example 1;

fig. 9 is a diagram of a modified cell architecture of example 2;

fig. 10 is a mobility management flow diagram of example 2;

fig. 11 is a schematic diagram illustrating that a source base station and a target base station share the same core network node in example 2;

fig. 12 is a re-configured cell architecture diagram of example 3;

fig. 13 is a mobility management flow diagram of example 3.

Detailed Description

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

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

How mobility management for a User Equipment (UE) moving between an LTE cell and a 5G cell in an inactive state or a light connected state is solved. In the related art, mobility between different RATs may be used as a reference, for example, handover between LTE and CDMA, handover between LTE and GSM, and handover between LTE and TD-SCDMA. None of these handovers consider the new state currently introduced by LTE and 5G.

Aiming at the problem of mobility management between LTE and 5G base stations in an RRC New state of LTE and 5G, the application provides a mobility management method and a mobility management device between LTE and 5G New RAT in an inactive state or a light connected state.

Example one

A mobility management method, as shown in fig. 1, may include:

step 101, determining a cell change mode of UE when the UE in an inactive state or a light-connected state meets a cell change condition and a target base station of a cell change is determined;

step 102, executing the switching of the UE according to the determined cell switching mode;

wherein the cell change mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; and transferring the user plane link of the UE to a target base station.

In practical applications, the method of this embodiment may be implemented by a source base station. In practical application, the target base station satisfies one of the following conditions: the RAT of the wireless access technology is the same as the source base station; the radio access technology RAT to which it belongs is not of the same class as the source base station.

In practical application, the determining the cell change mode of the UE includes: when the service type of the UE is the infrequent small data or the UE is judged to be temporarily out of the coverage range, determining to change the cell mode to keep the user plane of the UE linked to the source base station; and when the service type of the UE is not the infrequent small data and the UE is judged not to leave the coverage temporarily, determining a cell changing mode as transferring the user plane link of the UE to a target base station.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and sending a cell change request message to the target base station, wherein the cell change request message carries the cell change mode identifier, and the cell change mode identifier is used for identifying the determined cell change mode, namely the cell change mode identifier is used for identifying which cell change mode the source base station requires to adopt.

Here, the change cell request message may further include: and the source base station allocates an access stratum context identifier (AS context ID) of the UE, wherein the AS context identifier is used for identifying the identity of the UE at the source base station and storing the context of the UE at the source base station.

Wherein the performing handover of the UE according to the determined cell change manner comprises: receiving a change cell response message from a target base station, the change cell response message carrying one or more of the following: UE ID or AS context ID allocated to the UE by the target base station, and context established by the target base station for the UE; sending a cell change command message to the UE, wherein the cell change command message is used for indicating the UE to initiate a cell change to the target base station, and the cell change command message at least comprises a UE ID or an AS context ID allocated to the UE by the target base station.

Wherein, when the cell change mode is to keep the user plane of the UE linked to the source base station, the cell change command message may be further configured to instruct the UE to stop one or more of the following actions:

stopping the periodic monitoring of the physical channel of the source base station after the process of changing the cell is completed (for example, the periodic monitoring can include stopping the monitoring of a downlink control channel of the source base station, a paging channel of the source base station, a system message of the source base station, and the like);

Stop a RAN area update (RAN area notification update);

the measurement to the source base station is stopped.

Wherein, executing the handover of the UE according to the determined cell change mode comprises: and when the cell changing mode is to keep the user plane of the UE linked with the source base station, reserving functional entities of a PDCP layer, an RLC layer and an RRC layer corresponding to the UE at the source base station, and processing user plane data and control plane signaling which are transmitted to the source base station by the target base station, so that the target base station only completes MAC layer operation of the data and the signaling which are received and transmitted by the UE, namely MAC layer resource scheduling and MAC PDU packing/unpacking.

Wherein, executing the handover of the UE according to the determined cell change mode comprises: when the mode of changing the cell is to keep the user plane of the UE linked to the source base station, the request message of changing the cell carries the parts related to MAC scheduling, measurement, system message and physical layer in the UE context of the source base station, and does not contain the context parts related to PDCP, RLC and safety,

wherein the part related to MAC scheduling, measurement, system message and physical layer in the UE context of the source base station comprises one or a combination of the following parts:

UE cumulative Maximum Bit Rate (UE Aggregate Maximum Bit Rate);

established radio access bearer context (including Qos parameters of respective radio access bearers);

radio access capability information of the UE;

the AS configuration parameters include parts related to MAC scheduling, measurement, system information, and physical layer (e.g., antenna information, radio resource configuration, downlink carrier frequency, etc.);

part of the radio resource management, RRM, configuration parameters related to MAC scheduling, measurements, system messages, physical layer (e.g., ue-InactiveTime);

parts related to MAC scheduling, measurement, system message, physical layer in AS context (e.g., power saving Preference Indication, connection re-establishment information, etc.);

a mobility restriction list (containing serving PLMN, equivalent PLMN, forbidden access PLMN).

Wherein the performing the handover of the UE according to the determined cell change manner may further include: and when the cell changing mode is to keep the user interface of the UE linked to the source base station, after sending a cell changing command message to the UE, keeping the UE in an inactive state and storing the context of the UE. Here, the keeping the UE in an inactive state may include: and keeping the PDCP entity and the PDCP state, the RLC entity and the RLC state, the AS security information and the NAS security information of the UE at the source base station.

Wherein the performing handover of the UE according to the determined cell change manner further comprises: and when the cell changing mode is to keep the user plane link of the UE at a source base station, after sending a cell changing command message to the UE, receiving a notification message from a target base station and returning a response message to the target base station, wherein the notification message is used for notifying the source base station that the UE initiates access at the target base station, and the response message carries updated AS security information or NAS security information for the UE.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and when the mode of changing the cell is to transfer the user plane of the UE to be linked to the target base station, after confirming the target cell of the changed cell, the request message of the changed cell also comprises the PDCP state and the RLC state of the UE at the source base station.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and when the cell changing mode is to transfer the user plane link of the UE to the target base station, after receiving a cell changing response message from the target base station, sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspend (suspend) instruction, and the suspend instruction is used for instructing the UE to save the context of the source base station after the cell changing process is completed.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: when the cell change mode is to transfer the user plane link of the UE to the target base station, the cell change command message further includes: and the target base station side establishes context, AS security information or NAS security information for the UE.

Wherein the performing the handover of the UE according to the determined cell change mode comprises: and when the cell changing mode is to transfer the user plane link of the UE to a target base station, and when receiving an AS safety message or an NAS safety completion message fed back by the UE, transmitting the AS safety message or the NAS safety completion message to the target base station.

A mobility management apparatus, as shown in fig. 2, may include:

a first determining module 21, configured to determine a cell change mode of the UE after the inactive state or the light-connected state of the UE meets a cell change condition and a target base station of a cell change is determined;

a first handover module 22, configured to perform handover of the UE according to the determined cell change manner;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

And transferring the user plane link of the UE to a target base station.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes:

Wherein the cell change request message further comprises: and the source base station allocates an access stratum context identifier (AS context ID) of the UE, wherein the AS context identifier is used for identifying the identity of the UE at the source base station and storing the context of the UE at the source base station.

When the cell change mode is to keep the user plane of the UE linked to the source base station, the cell change command message is further used to instruct the UE to stop one or more of the following actions:

stopping a RAN area notification update (RAN area notification update);

the measurement to the source base station is stopped.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane of the UE linked to the source base station, reserving functional entities corresponding to a PDCP layer, an RLC layer and an RRC layer of the UE at the source base station, and processing user plane data and control plane signaling which are transmitted to the source base station by the target base station so that the target base station only completes MAC layer operation of the data and the signaling which are received and transmitted by the UE.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: when the cell change mode is to keep the user plane of the UE linked to the source base station, the cell change request message carries the parts related to MAC scheduling, measurement, system messages and a physical layer in the UE context of the source base station, and does not contain the context parts related to PDCP, RLC and safety.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane of the UE linked to the source base station, keeping the UE in an inactive state and storing the context of the UE.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: and when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving a notification message from the target base station and returning a response message to the target base station, wherein the notification message is used for notifying the source base station that the UE initiates access at the target base station, and the response message carries updated AS security information or NAS security information for the UE.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: when the cell changing mode is to transfer the user plane link of the UE to a target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, the suspension instruction is used for indicating the UE to save a source base station context after the cell changing is finished, and the source base station side context of the UE is saved after the cell changing command message is sent to the UE; or when the cell changing mode is to transfer the user plane link of the UE to the target base station, receiving a cell changing response message from the target base station, sending a cell changing command message to the UE, and deleting the context of the source base station side of the UE.

The first handover module 22 is configured to perform handover of the UE according to the determined cell change mode, and includes: when the cell change mode is to transfer the user plane of the UE to link to the target base station, the cell change command message further includes: and the target base station side establishes context, AS security information or NAS security information for the UE.

Still another mobility management apparatus, comprising: a processor and a memory, the memory storing computer-executable instructions that, when executed by the processor, implement a method comprising:

In this embodiment, the first determining module and the first switching module may be implemented by software, hardware, or a combination of the two. In practical applications, the first determining module may be implemented by a communication unit in a base station or the like, and the first switching module may be implemented by a processor, a communication unit, or the like in the base station or the like. The mobility management apparatus of the present embodiment may be implemented by being deployed on a base station or the like or directly implemented by a UE or the like. And are not limited in this context.

All the details of the method of this embodiment can be implemented by both of the mobility management apparatuses of this embodiment, and the implementation principle is the same, and reference may be made to the related description of the method above.

Example two

A mobility management method, as shown in fig. 3, may include:

step 301, receiving a cell change request message from a source base station, where the cell change request message at least carries a cell change mode identifier, and the cell change mode identifier indicates a cell change mode determined by the source base station;

step 302, according to the cell changing mode indicated by the cell changing request message, executing the switching of UE;

wherein the cell change mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; transferring the user plane link of the UE to a target base station.

In practical applications, the method of this embodiment may be implemented by the target base station. In practical applications, the target base station may satisfy one of the following conditions: the RAT of the wireless access technology is the same as the source base station; the radio access technology RAT to which it belongs is not of the same class as the source base station.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: according to the cell change request message, after the UE is confirmed to be admitted, a UE ID is distributed to the UE for identifying the identity of the UE in a target base station; or, allocating an AS context ID to the UE for identifying the identity of the UE at the target base station and storing the context of the UE at the target base station.

Wherein, after receiving the cell change request message from the source base station, the method further comprises: and after the target base station confirms to accept the UE to change the cell, feeding back a response message of the cell to be changed to the source base station, wherein the response message of the cell to be changed comprises the UE ID or AS context ID allocated to the UE by the target base station.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: and when the cell change mode is that the user plane link of the UE is kept at the source base station, after the cell change of the UE is admitted, according to the context content of the UE contained in the cell change request message, establishing the related configuration of an MAC entity and a physical layer corresponding to the UE, and establishing the corresponding relationship between the MAC entity and the PDCP and RLC entities of the UE at the source base station.

Wherein, when the cell change mode is that the user plane link of the UE is maintained at the source base station, the cell change response message further includes: and the target base station configures the MAC for the UE and the configuration parameters related to the physical layer. Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message further includes: and when the cell changing mode is to keep the user plane link of the UE at the source base station, confirming the identity of the UE according to the UE ID sent when the UE accesses the cell changing mode, and sending a notification message to the source base station, wherein the notification message is used for informing the source base station that the UE initiates access at the target base station.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message further includes:

and when the cell changing mode is to keep the user plane of the UE linked to the source base station, sending a first indication to the UE, wherein the first indication is used for informing the UE to use a PDCP entity, an RLC entity, AS security and NAS security of the source base station to carry out PDCP layer operation and RLC operation of data and signaling, and encryption and decryption of the AS security and the NAS security. Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes:

and when the cell change mode is to transfer the user plane link of the UE to a target base station, after determining to accept the cell change requirement of the UE, establishing a complete context, a user plane connection, a control plane connection and a connection with a core network corresponding to the UE according to the context content of the UE contained in the cell change request message. Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: and when the cell changing mode is to transfer the user plane link of the UE to the target base station, the cell changing response message also comprises the context of the target base station side established for the UE.

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: and when the cell changing mode is to transfer the user plane link of the UE to the target base station, the cell changing response message also comprises AS safety information and NAS safety information which are established for the UE by the target base station. Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: when the cell change mode is to transfer the user plane link of the UE to the target base station, and when the source base station and the target base station share the same core network node, the cell change response message also contains AS security information established by the target base station for the UE, no NAS security information and an identifier, wherein the identifier is used for informing the UE that the NAS security information of the source cell is reserved after the cell change is completed so AS to reuse the NAS security information in the target base station

Wherein, the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes: when the cell changing mode is to transfer the user plane link of the UE to a target base station, after receiving an access process initiated by the UE and an AS context ID in the access process, confirming the identity of the UE and the established context of the UE, and feeding back a state transfer message to the UE, wherein the state transfer message is used for indicating the UE to set the self state to an inactive state or a light connected state. Specifically, if the target base station is a 5G-gbb, the state transition message is used to instruct the UE to set its own state as an inactive state; and if the target base station is an LTE eNB, the state transfer message is used for indicating the UE to set the self state to a light connected state.

A mobility management apparatus, as shown in fig. 4, may include:

a second receiving module 41, configured to receive a cell change request message from a source base station, where the cell change request message at least carries a cell change mode identifier, and the cell change mode identifier indicates a cell change mode determined by the source base station;

a second switching module 42, configured to execute a UE switching according to the cell change mode indicated by the cell change request message;

The cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring the user plane link of the UE to a target base station.

The second handover module 42 is configured to execute handover of the UE according to the cell change mode indicated by the cell change request message, and includes:

when the cell change mode is to transfer the user plane link of the UE to the target base station, and when the source base station and the target base station share the same core network node, the cell change response message further includes AS security information established by the target base station for the UE, no NAS security information and an identifier, wherein the identifier is used for informing the UE that the NAS security information of the source cell is reserved for reuse in the target base station after the cell change is completed.

when the cell changing mode is to transfer the user plane link of the UE to the target base station, when receiving an AS security completion message of the UE transparently transmitted by the source base station, confirming that AS security negotiation is completed; and when receiving the NAS security completion message of the UE transparently transmitted by the source base station, forwarding the NAS security completion message to a core network to complete the negotiation confirmation of NAS security.

the cell change mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; and transferring the user plane link of the UE to a target base station.

In this embodiment, the second receiving module and the second switching module may be implemented by software, hardware, or a combination of the two. In practical applications, the second receiving module may be implemented by a communication unit in a base station or the like, and the second switching module may be implemented by a processor, a communication unit, and the like in the base station or the like. The mobility management apparatus of the present embodiment may be implemented by being deployed on a base station or the like or directly implemented by a UE or the like. And are not limited in this context.

All the details of the method of this embodiment can be implemented by both of the above two mobility management devices of this embodiment, and the implementation principle is the same, and reference may be made to the related description of the method above.

EXAMPLE III

A mobility management method, as shown in fig. 5, may include:

step 501, receiving a cell change command message issued by a source base station, where the cell change command message is used to instruct a UE to initiate a cell change to a target base station, and the cell change command message at least carries a cell change mode identifier determined by the source base station;

step 502, executing switching according to the cell switching mode indicated by the cell switching command message;

The cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

In practical applications, the method of the present embodiment may be implemented by a UE. In practical applications, the target base station may satisfy one of the following conditions: the RAT of the wireless access technology is the same as the source base station; the radio access technology RAT to which it belongs is not of the same class as the source base station.

Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: acquiring a UE ID or an AS context ID distributed to the UE by the target base station from the command message for changing the cell; and initiating access to a target base station, and reporting the UE ID or AS context ID allocated to the UE by the target base station to the target base station in the access process.

Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: and the cell changing mode is to keep the state of the UE in the source base station and save the context of the UE in the source base station when the user plane of the UE is linked to the source base station.

Wherein the maintaining of the state of the self at the source base station comprises: keeping the PDCP entity and the PDCP state, the RLC entity and the RLC state, the AS security information and the NAS security information of the source base station.

Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises:

wherein the behavior of the corresponding item comprises one or more of:

stopping the periodic monitoring of the physical channel of the source base station (including stopping the monitoring of a downlink control channel of the source base station, a paging channel of the source base station and system messages of the source base station);

stopping RAN area update;

the measurement to the source base station is stopped.

Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: and the cell changing mode is that when the user plane of the UE is kept to be linked with a source base station, after the target base station is accessed, the PDCP entity, the RLC entity, the AS security information and the NAS security information of the source base station which are kept by the user plane are used for processing the operations of the PDCP layer and the RLC layer, the AS encryption and decryption, the NAS encryption and decryption and the integrity protection when receiving and sending data or signaling.

Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: and the cell changing mode is that when the user plane of the UE is kept linked to a source base station, after the AS security information or the NAS security information from the source base station which is transmitted by the target base station in a transparent way is updated, the AS encryption and decryption, the NAS encryption and decryption and integrity protection of data or signaling are completed by adopting the updated AS security information or the NAS security information.

Wherein, executing the switch according to the cell changing mode indicated by the cell changing command message comprises: when the cell changing mode is to transfer the user plane link of the UE to the target base station: when the command message for changing the cell carries the context of the target base station side established by the target base station for the UE, acquiring and storing the context of the target base station side from the command message for changing the cell; when the command message for changing the cell carries AS security information, completing AS security key negotiation according to the AS security information, and when the key negotiation is successful, sending an AS security completion message to a target base station through a source base station; and when the NAS security information is carried in the command message for changing the cell, completing NAS security key negotiation according to the NAS security information, and transmitting the NAS security completion message to a core connected with the target base station through the source base station when the key negotiation is successful.

Wherein, executing the switch according to the cell changing mode indicated by the cell changing command message comprises: and the cell changing mode is to transfer the state of the user plane of the UE in the source base station to an IDLE state when the user plane of the UE is transferred to the target base station.

And if the change cell command message contains the identifier indicating that the UE retains the NAS security information of the source cell after the change cell is completed, the UE retains the NAS security information of the source cell after the change cell is completed.

Wherein, executing the switch according to the cell changing mode indicated by the cell changing command message comprises: when the user plane of the UE is transferred to a target base station and a suspension instruction is carried in the cell change command message, saving the context of a source base station side according to the suspension instruction; and deleting the context of the source base station side when the command message for changing the cell does not carry the suspension indication. Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: and the cell changing mode is that when the user plane of the UE is transferred to be linked to the target base station, the state of the UE in the source base station is transferred to be an IDLE state, and the UE initiates access to the target base station. Wherein, executing the switching according to the switching cell mode indicated by the switching cell command message comprises: and when the cell changing mode is to transfer the user plane of the UE to be linked to a target base station, receiving a state transfer message from the target base station, and setting the state of the target base station in an inactive state or a light connected state according to the state transfer message. If the target base station is 5G-gNB, setting the state of the target base station as an inactive state; and if the target base station is the LTE eNB, setting the state of the target base station as a light connected state.

Wherein, executing the switch according to the cell changing mode indicated by the cell changing command message comprises: and the cell changing mode is that when the user plane of the UE is transferred to be linked to the target base station, the state of the UE in the source base station is transferred to an IDLE state after the switching is finished.

A mobility management apparatus, as shown in fig. 6, may include:

a third receiving module 61, configured to receive a cell change command message issued by a source base station, where the cell change command message is used to instruct a UE to initiate a cell change to a target base station, and the cell change command message at least carries a cell change mode identifier determined by the source base station;

a third switching module 62, configured to execute switching according to the cell change mode indicated by the cell change command message;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

The third handover module 62 is configured to execute handover according to the cell change mode indicated by the cell change command message, and includes:

wherein the behavior of the corresponding item comprises one or more of:

The measurement to the source base station is stopped.

The third handover module 62 is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

and when the cell changing mode is to keep the user plane of the UE linked to a source base station, after receiving the update of AS security information or NAS security information from the source base station, which is transmitted by the target base station in a transparent way, the AS security information or NAS security information is adopted to complete AS encryption and decryption, NAS encryption and decryption and integrity protection of data or signaling.

The third handover module 62 is configured to execute handover according to the cell change mode indicated by the cell change command message, and includes: and the cell changing mode is to transfer the state of the UE in the source base station to an IDLE state after the switching is finished when transferring the user plane of the UE to be linked to the target base station.

Another mobility management apparatus includes: a processor and a memory, the memory storing computer-executable instructions that, when executed by the processor, implement a method comprising:

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

and transferring the user plane link of the UE to a target base station.

In this embodiment, the third receiving module and the third switching module may be implemented by software, hardware, or a combination of the two. In practical applications, the third receiving module may be implemented by a communication unit in the UE or similar device, and the third switching module may be implemented by a combination of a processor, a communication unit, and the like in the UE or similar device. The mobility management apparatus of the present embodiment may be implemented by being deployed on or directly implemented by a UE or similar device. And are not limited in this context.

The present application is described in detail below by taking the following three examples as examples.

Example 1

The scenario of this example is: two adjacent base stations are respectively a 5G base station and an LTE base station, a UE which supports 5G and LTE simultaneously moves from the 5G base station to the LTE base station, the UE is in an inactive state at the 5G base station, when the UE is in the inactive state, the RRC connection between the UE and the RAN is still kept, the signaling bearer and the data bearer are still kept, but the difference from the RRC connection state is that: the terminal and RAN need to store the context of the terminal, the mobility of the terminal adopts a cell reselection mode, and the terminal monitors the paging of the RAN and the CN. The definition of light connected state in LTE is similar to inactive state in 5G.

In this example, mobility management of a UE moving from a 5G base station to an LTE base station is described in detail, and fig. 7 is an architecture diagram of this example. As shown in fig. 8, the mobility management procedure in this example may include:

step 701, UE measures signal quality of a current service base 5G-gNB and an adjacent cell, and reports a measurement result to the 5G-gNB when detecting that the measurement result meets an inter-RAT (inter-system) switching condition;

in step 702, the current serving base station 5G-gNB determines to change the UE to an adjacent inter-system cell, i.e. an eNB of LTE system. The 5G-gNB decides which mobility architecture to adopt,

If the service data of the UE is mainly infrequent small data, the transmission is mostly carried out in an inactive state; then, the 5G-gNB may choose to leave the user plane anchor point in the 5G-gNB without transferring to the LTE eNB, because the data transmission of this service model does not bring extra air interface overhead, and the cost is only an increase in traffic of the interface between 2 base stations.

If the UE leaves the 5G-gNB cell only for a short time and returns within a short time, the 5G-gNB can choose to leave the user plane anchor point at the 5G-gNB without transferring to the LTE eNB, so that an extra handover from the LTE eNB to the 5G-gNB can be avoided.

Step 703, the 5G-gNB sends a cell change request message to the target base station LTE eNB;

in practical applications, the handover request message may adopt a structure similar to that of the handover request message of LTE.

The change cell request message may include: part of the UE context related to MAC scheduling, measurement, system messages, physical layer.

Wherein, the part related to the MAC scheduling, measurement, system message and physical layer in the UE context may include one or more of the following items:

UE cumulative Maximum Bit Rate (UE Aggregate Maximum Bit Rate);

an established LTE Radio Access Bearer (E-RAB, E-UTRAN Radio Access Bearer) context (including QoS parameters of each E-RAB);

Radio access capability information of the UE;

the AS configuration parameters include the parts related to MAC scheduling, measurement, system information and physical layer (such AS antenna information, radio resource configuration, downlink carrier frequency and the like);

the parts of the Radio Resource Management (RRM) configuration parameters related to MAC scheduling, measurements, system messages, physical layer, such as: terminal inactivity time (ue-InactiveTime);

parts of the AS context related to MAC scheduling, measurement, system messages, physical layer, for example: power saving tendency Indication (power Preference Indication), connection reestablishment information;

and the mobility restriction list comprises a service PLMN, an equivalent PLMN, a PLMN which is forbidden to be accessed and the like.

In addition, if the source base station 5G-gNB and the target LTE eNB support multiple cell change modes, optionally, the cell change request message may include a selection indication of the source base station 5G-gNB for the cell change mode, that is: whether to move the user plane anchor of the UE to the target base station or remain at the source base station is selected.

Optionally, the cell change request message may include an AScontext ID (access stratum context identifier) allocated by the 5G-gNB to the UE, where the AS context ID is used to identify the identity of the UE and the context storage of the UE in the 5G-gNB.

Step 704, the target base station eNB judges whether to admit the UE according to the received request for changing the cell, and if not, feeds back a rejection message; if the cell is admitted, allocating a UE ID within the range of the eNB for the UE, and returning a cell change response;

in practical application, the UE ID may be a Cell-Radio Network Temporary Identifier (C-RNTI) of an LTE scheme.

Optionally, the target base station eNB may establish, according to context content of the UE included in the cell change request, configuration related to an MAC entity and a physical layer corresponding to the UE, and establish a correspondence between the MAC entity and PDCP and RLC entities of the UE in the 5G-gNB.

In practical application, the target base station eNB accepts the UE, and may feed back a handover cell response message to the source base station 5G-gNB, where the handover cell response message includes the UE ID allocated by the eNB. Here, the change cell response message may further include a MAC configured by the eNB for the UE and a configuration parameter related to a physical layer.

Step 705, the source base station 5G-gNB sends a change cell command message to the UE, indicating that the UE can move to the target eNB, where the change cell command message includes a UE ID allocated by the target eNB to the UE;

Optionally, the cell change command message includes an identifier of a mobility management architecture adopted in the current mobility process: namely, selecting to keep the user plane anchor point at the source base station or move the anchor point to the target base station;

optionally, the UE is instructed to stop the periodic listening to the physical channel of the 5G-gNB in the cell change order message, for example: stopping monitoring the 5G-gNB downlink control channel, the 5G-gNB paging channel and the 5G-gNB system message;

optionally, the UE is instructed to stop the RAN area notification update (RAN area update) in the cell change command message unless the user plane anchor of the UE is changed;

optionally, the UE is instructed to stop the measurement at the 5G-gNB in the cell change order message.

Step 706, the 5G-gbb still keeps the UE in inactive state, and saves the context of the UE;

correspondingly, the UE acquires a target base station of a changed cell and a framework adopted by the current mobility management according to the received command message of the changed cell, namely, the user plane anchor point is kept at 5G-gNB, the target base station eNB only completes the MAC layer scheduling function of the user plane, and then the UE keeps the state of inactive at 5G-gNB and stores the context of 5G-gNB.

Optionally, the UE stops monitoring the 5G-gNB downlink control channel, the 5G-gNB paging channel, and the 5G-gNB system message according to the received cell change command message; stopping RAN area notification update; stopping the measurement at 5G-gNB;

step 707, the UE initiates access to the target base station eNB by using the UE ID allocated by the target base station eNB, establishes an initial Signaling Bearer (SRB0, Signaling Radio Bearer 0) during the access, and reports the UE ID allocated to the UE by the eNB to the eNB through a message of SRB 0;

step 708, the eNB confirms that the identity of the UE is the received UE moving from the 5G-gNB according to the received UE ID, and sends a notification to the 5G-gNB to notify that the UE initiates access at the eNB;

step 709, the 5G-gNB sends a response message to the eNB, optionally, the response message may carry updated AS security information or NAS security information;

in step 710, the eNB sends MAC layer related configuration parameters, such as DRX (discontinuous reception) and HARQ (hybrid automatic repeat request) parameters, to the UE, and sends physical layer related configuration parameters, such as PUCCH (physical uplink control channel) and SRS (Sounding Reference Signal) to the UE.

Optionally, if there is an update of the AS security information or NAS security information sent by the 5G-gbb to the UE, the update is passed through to the UE;

Optionally, the eNB sends an indication to the UE to inform the UE that the user plane anchor is still at the 5G-gNB, and therefore the user plane (i.e. PDCP, RLC, AS security) and control plane (NAS security, RRC signaling) of the 5G-gNB are still used in addition to the MAC and physical layer

Step 711, the eNB may delete SRB 0;

step 712, transceiving UL/DL data/signaling, the UE processes PDCP layer, RLC layer operation, AS ciphering and deciphering, NAS ciphering and deciphering, integrity protection using the PDCP entity, RLC entity, AS security information, NAS security information of the eNB held by the UE.

Optionally, if the UE receives the update of the AS security information or the NAS security information sent by the 5G-gNB to the UE in step 710, the AS encryption/decryption, NAS encryption/decryption, and integrity protection of the data or signaling are completed by using the updated AS security information or NAS security information.

In this example, as shown in fig. 7, after the mobility process is completed, the user plane anchor point of the UE is maintained at the source base station 5G-gNB, that is, the source base station retains the PDCP layer, the RLC layer, and the RRC layer functional entity corresponding to the UE, and the target base station LTE eNB only establishes the MAC layer functional entity corresponding to the UE, and the user plane data and the control plane signaling received and transmitted by the UE at the target base station eNB are transparently transmitted to the source base station 5G-gNB where the user plane anchor point is located by the target base station eNB for processing, and the target base station eNB is only responsible for performing MAC layer resource scheduling and MAC PDU packing/unpacking.

Example 2

In the same scenario as example 1, when the UE moves from the 5G base station to the LTE base station, the UE performs handover by moving the user plane anchor to the target base station. After the mobility process is finished, transferring a user plane anchor point of the UE to a target base station, and establishing context, AS connection and core network connection of the UE in the target base station by the target base station according to the UE context sent by a source base station; and the source base station deletes the context of the UE after the switching is completed.

Fig. 9 is an architectural diagram of the present example. As shown in fig. 10, the mobility management procedure in this example may specifically include:

step 901, the UE measures the signal quality of the current serving base station 5G-gNB and the neighboring cell, and reports the measurement result to the 5G-gNB when detecting that the measurement result meets the inter-RAT (inter-system) handover condition;

in step 902, the current serving base station 5G-gNB determines to move the UE to an adjacent inter-system cell, i.e. an eNB of LTE system. The 5G-gNB decides which mobility architecture to employ;

if the service of the UE contains big data or the UE does not return to the coverage of the source base station within a short time, the source base station 5G-gNB selects to transfer the user plane anchor point to the target base station, which can reduce the traffic overhead of the base station interface and reduce the end-to-end transmission delay of data.

Step 903, the 5G-gNB sends a cell change request message to a switched target base station LTE eNB;

for the present example, since the user plane anchor point is to move to the target base station and is a process triggered in the inactive state, this process may be called inactive handover, this message is instead called an inactive handover request, this message is used to indicate that this handover is for the UE in the inactive state, for example, a structure of a handover request message similar to LTE may be used, and the inactive handover request message includes: UE complete context;

optionally, if the UE is in the data transceiving stage at the source base station, the inactive handover request message may further include a PDCP state and an RLC state of the UE at the source base station, so as to ensure continuity of data transmission of the UE after handover to the target base station;

in addition, if the source base station 5G-gNB and the target LTE eNB support multiple mobility architectures, optionally, the inactive handover request message includes a selection indication of the source base station 5G-gNB for changing the cell mode, that is: selecting whether to move the user plane anchor point of the UE to a target base station or to remain in a source base station;

step 904, the target base station eNB judges whether to admit the UE according to the received mobile request, and feeds back a rejection message if not; if the UE is admitted, a UE ID within the range of the eNB is distributed to the UE;

For example, the UE ID may be C-RNTI (Cell-Radio Network Temporary Identifier) of LTE system; or resume ID, which is used to identify the UE identity at the target base station eNB and the UE context storage at the target base station.

Optionally, the eNB establishes a context, a user plane connection, a control plane connection, and a connection with the core network corresponding to the UE according to the context content of the UE included in the mobile request.

Step 905, if the target base station eNB accepts the UE, feeding back inactive handover response information to the source base station 5G-gNB, where the inactive handover response information includes the UE ID or the resume ID allocated by the eNB; optionally, the inactive handover response message further includes a context of the target base station side established by the eNB for the UE. Optionally, the inactive handover response message further includes AS security information and NAS security information established by the target base station for the UE.

If the source base station and the target base station share the same Core network node as in fig. 11, the source base station and the target base station of the heterogeneous system may share the same EPC (Evolved Packet Core) Core network node, or may share the same 5G NGC (Next Generation Core) Core network node. If two base stations of different systems share the same EPC core network node, only a UP (User Plane) interface is arranged between the 5G gNB and the EPC core network node; if two base stations of different systems share the same 5G NGC core network node, a CP (Control Plane) interface and a UP (User Plane) interface are arranged between the 5G gNB, eLTE (Evolved LTE) eNB and the 5G NGC core network node, a target base station does not need to send NAS (network attached storage) safety information for the UE, and the NAS safety information of the UE on a source base station can be reused on the target base station; optionally, the target base station may add an identifier in the inactive handover response message to notify the UE to retain NAS security information after the handover is completed, and may reuse the NAS security information in the target base station.

Step 906, the source base station 5G-gNB sends an inactive handover command message to the UE, indicating that the UE can move to the target eNB, the inactive handover command message including a UE ID or a resume ID allocated by the target eNB to the UE;

optionally, the inactive handover command message includes an identifier of a mobility management architecture adopted in the current mobility process; namely: the distinction is whether to choose to move the user plane anchor of the UE to the target base station or to remain at the source base station.

Optionally, the inactive handover command message includes an indication that the UE is required to delete the context of the source base station after the handover procedure is completed.

Optionally, the context, AS security information, and NAS security information that are established for the UE by the target base station side that is sent to the UE by the target base station in step 404 are transmitted to the UE in the inactive handover command message.

Step 907, the UE learns the target base station to be switched according to the received inactive handover command message, and learns that the cell change mode adopted by the current mobility management is a cell change mode for transferring the user plane anchor point to the target base station. If the UE receives the context, AS security information and NAS security information which are established for the UE by the target base station side in the inactive switching command message, storing the context, and completing the key negotiation process of AS security and NAS security according to the AS security information and the NAS security information; UE sends AS safety completion information and NAS safety completion information to a source base station;

Step 908, the source base station transmits the AS and NAS security completion message to the target base station;

step 909, the target base station receives the AS security complete message or NAS security complete message forwarded by the UE through the source base station, confirms that the AS security negotiation is complete, and forwards the NAS security complete message to the core network to complete the NAS security negotiation process;

in step 910, the source base station 5G-gNB deletes the user plane connection and the control plane connection of the UE, deletes the context of the UE, and transfers the UE state to the IDLE state.

Step 911, corresponding to step 910, the UE deletes its own source base station 5G-gNB context, and transfers its own state to IDLE state.

In practical application, if the UE receives the identifier sent by the target base station, and informs the UE to reserve NAS security information after the handover is completed and to reuse the NAS security information in the target base station, the UE reserves the NAS security information and does not delete the NAS security information.

Step 912, the UE initiates access to the target base station eNB, establishes an initial Signaling Bearer (SRB0, Signaling Radio Bearer 0) during the access, and reports the UE ID or resume ID allocated to the UE by the target base station eNB to the target base station eNB;

step 913, the target base station eNB confirms that the UE identity is the received UE moving from the 5G-gNB according to the received UE ID or the resume ID, and confirms that the context of the UE is established, and the target base station eNB feeds back a state transfer message to the UE, indicating that the UE sets its own state as light connected.

In step 914, the UE sets its own state in the eNB to light connected according to the state transition message sent by the target eNB.

Example 3

The scenario of the embodiment is the same AS that of embodiment 1, in the embodiment, the UE is switched in a mode of moving the user plane anchor point to the target base station in the process of moving from the 5G base station to the LTE base station, after the mobility process is finished, the user plane anchor point of the UE is transferred to the target base station, and the target base station newly establishes the context, AS connection and core network connection of the UE at the target base station according to the UE context sent by the source base station; and the source base station saves the context of the UE after the switching is completed. So that the UE can recover and connect to the 5G-gNB more efficiently after returning to the source base station 5G-gNB later.

Fig. 12 is an architecture diagram of the present example, and the mobility management procedure of the present example shown in fig. 13 may include:

1001-1002, the same as the step 901-902 of the example 2;

step 1003, same as step 903 of example 2;

optionally, the cell change request message includes an AS context ID (access stratum context identifier) allocated by the 5G-gNB to the UE, where the AS context ID is used to identify an identity of the UE in the 5G-gNB and a context storage of the UE in the 5G-gNB;

1004 to 1005, as with 904 to 905 of example 2;

Step 1006, as in step 906 of example 2,

in addition, optionally, the inactive handover command message includes a suspend indication, which is used to inform the UE to save the context of the 5G-gNB after the handover procedure is completed;

step 1007-1009, like step 907-909 of example 2;

step 1010, the source base station 5G-gNB deletes the user plane connection and the control plane connection of the UE, but saves the context of the UE, and transfers the UE state to the IDLE state.

Step 1011, corresponding to this, the UE saves its own source base station 5G-gNB context, and transfers its own state in 5G-gNB to IDLE state.

Steps 1012 to 1014, similar to steps 912 to 914 of example 2;

step 1015, if the UE returns to the coverage of the 5G-GNB again later, the UE may report the AS context ID allocated to the UE before the 5G-GNB in the process of accessing the 5G-GNB, the 5G-GNB may query the stored context of the UE accordingly, and the 5G-GNB may restore the AS connection and the core network connection of the UE according to the context storage of the UE, or migrate the UE to an inactive state.

In all the above examples, the types of the access network elements include small cells, home base stations, and other types of access network elements compatible with the EPC architecture, in addition to the LTE eNB, 5G gbb. The types of the core network elements include core network elements supporting a 5G system, machine type communication and mobility management, such as C-SGN, NBIoT MME, 5G CN core, and the like, in addition to MME.

In addition, an embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions, and when executed, the computer-executable instructions implement the foregoing mobility management method.

In addition, an embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions, and when the computer-executable instructions are executed, the method for mobility management is implemented as another mobility management method described above.

In addition, an embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions, and when the computer-executable instructions are executed, the method for mobility management is further described above.

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

Optionally, in this embodiment, the processor executes the method steps of the above embodiments according to the program code stored in the storage medium.

Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation manners, and this embodiment is not described herein again.

It will be understood by those skilled in the art that all or part of the steps of the above methods may be implemented by a program instructing associated hardware (e.g., a processor) to perform the steps, and the program may be stored in a computer readable storage medium, such as a read only memory, a magnetic or optical disk, and the like. Alternatively, all or part of the steps of the above embodiments may be implemented using one or more integrated circuits. Accordingly, the modules/units in the above embodiments may be implemented in hardware, for example, by an integrated circuit, or may be implemented in software, for example, by a processor executing programs/instructions stored in a memory to implement the corresponding functions. The present application is not limited to any specific form of hardware or software combination.

The foregoing shows and describes the general principles and features of the present application, together with the advantages thereof. The present application is not limited to the above-described embodiments, which are described in the specification and drawings only to illustrate the principles of the application, but also to provide various changes and modifications within the spirit and scope of the application, which are within the scope of the claimed application.

Claims

1. A mobility management method, comprising:

determining a cell changing mode of User Equipment (UE) after the UE in an inactive state or a light-connected state meets the condition of changing a cell and a target base station of the cell is determined;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

when the cell change mode is to keep the user plane of the UE linked to the source base station, sending a cell change command message to the UE, wherein the cell change command message is further used for instructing the UE to stop one or more of the following behaviors:

stopping a RAN area notification update (RAN area notification update);

stopping the measurement of the source base station;

the performing the handover of the UE according to the determined cell change manner includes:

when the cell changing mode is to keep the user plane of the UE linked to the source base station, functional entities corresponding to a PDCP layer, an RLC layer and an RRC layer of the UE are reserved at the source base station, and user plane data and control plane signaling transmitted from the target base station to the source base station are processed, so that the target base station only completes MAC layer operation of the data and the signaling received and transmitted by the UE;

The performing the handover of the UE according to the determined cell change manner further includes:

and when the cell changing mode is to transfer the user plane link of the UE to a target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, and the suspension instruction is used for indicating the UE to save the context of the source base station after the cell changing is finished, and besides sending the cell changing command message to the UE, saving the context of the source base station side of the UE.

2. The mobility management method of claim 1, wherein the target base station satisfies one of the following:

3. The mobility management method of claim 1, wherein the performing the handover of the UE according to the determined cell change manner comprises:

4. The mobility management method according to claim 1,

sending a cell change request message to the target base station, wherein the cell change request message further comprises: and the source base station allocates an access stratum context identifier (AS context ID) of the UE, wherein the AS context identifier is used for identifying the identity of the UE at the source base station and storing the context of the UE at the source base station.

5. The mobility management method of claim 1, wherein the performing the handover of the UE according to the determined cell change manner comprises:

sending a cell change command message to the UE, wherein the cell change command message is used for indicating the UE to initiate a cell change to the target base station, and the cell change command message at least comprises a UE ID or an AS contextID allocated to the UE by the target base station.

6. The mobility management method of claim 1, wherein performing the handover of the UE according to the determined cell change mode comprises:

And when the cell changing mode is to keep the user plane of the UE linked to the source base station, sending a cell changing request message to the target base station, wherein the cell changing request message carries parts related to MAC scheduling, measurement, system messages and a physical layer in the UE context of the source base station, and does not contain the context parts related to PDCP, RLC and safety.

7. The mobility management method of claim 1, wherein the performing the handover of the UE according to the determined cell change manner comprises:

and when the cell changing mode is to keep the user plane of the UE linked to the source base station, keeping the UE in an inactive state and storing the context of the UE.

8. The mobility management method of claim 1, wherein the performing handover of the UE according to the determined cell change manner comprises one or both of:

when the cell changing mode is to keep the user plane link of the UE at a source base station, receiving a notification message from a target base station, wherein the notification message is used for informing the source base station that the UE has accessed at the target base station;

and after the UE is known to be accessed in the target base station, sending updated AS security information or NAS security information to the UE to the target base station.

9. The mobility management method of claim 1, wherein the performing handover of the UE according to the determined cell change manner comprises:

when the cell changing mode is to transfer the user plane link of the UE to the target base station, sending a cell changing command message to the UE, wherein the cell changing command message further comprises: and the target base station side establishes context, AS security information or NAS security information for the UE.

10. A mobility management apparatus, comprising:

the first determining module is used for determining a cell changing mode of User Equipment (UE) after the UE in an inactive state or a light-connected state meets the condition of changing a cell and a target base station of the changed cell is determined;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

stop a RAN area update (RAN area notification update);

stopping the measurement of the source base station;

the first handover module is configured to perform handover of the UE according to the determined cell change mode, and includes:

and when the cell changing mode is to transfer the user plane link of the UE to the target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, and the suspension instruction is used for indicating the UE to save the source base station context after finishing changing the cell, and saving the source base station side context of the UE after sending the cell changing command message to the UE.

11. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change manner, and comprises:

12. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and comprises:

13. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and comprises:

receiving a change cell response message from a target base station, the change cell response message carrying one or more of the following: UE ID or AS context ID allocated to the UE by the target base station, and context established by the target base station for the UE;

And sending a cell change command message to the UE, wherein the cell change command message is used for indicating the UE to initiate a cell change to the target base station, and the cell change command message at least comprises a UE ID or an AS context ID allocated to the UE by the target base station.

14. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change manner, and comprises:

15. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and comprises:

16. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change manner, and comprises:

and when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving a notification message from the target base station and returning a response message to the target base station, wherein the notification message is used for notifying the source base station that the UE is accessed at the target base station, and the response message carries updated AS security information or NAS security information for the UE.

17. The mobility management apparatus of claim 10, wherein the first handover module is configured to perform handover of the UE according to the determined cell change mode, and comprises:

when the cell change mode is to transfer the user plane link of the UE to the target base station, sending a cell change command message to the UE, wherein the cell change command message further comprises: and the target base station side establishes context, AS security information or NAS security information for the UE.

18. A mobility management method, comprising:

receiving a cell change request message from a source base station under the condition that User Equipment (UE) in an inactive state or a light-connected state meets the cell change condition and a target base station of the cell change is determined, wherein the cell change request message at least carries a cell change mode identifier which represents the cell change mode determined by the source base station;

the cell changing mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

when the cell change mode is to keep the user plane link of the UE to the source base station, the source base station is further configured to send a cell change command message to the UE, where the cell change command message is further configured to instruct the UE to stop one or more of the following actions:

stop a RAN area update (RAN area notification update);

stopping the measurement of the source base station;

the performing the handover of the UE according to the cell change mode indicated by the cell change request message includes:

when the cell changing mode is to keep the user plane link of the UE at a source base station, receiving updated AS security information or NAS security information from the source base station to the UE, and transmitting the updated AS security information or NAS security information to the UE;

And when the cell changing mode is to transfer the user plane link of the UE to a target base station, and when the source base station and the target base station share the same core network node, sending a cell changing response message to the source base station, wherein the cell changing response message comprises AS security information established by the target base station for the UE and an NAS security information holding identifier, and the NAS security information holding identifier is used for informing the UE of holding the NAS security information of the source cell for reuse in the target base station after the cell changing is completed.

19. The mobility management method according to claim 18, wherein the performing handover of the UE according to the cell change mode indicated by the cell change request message comprises:

20. A mobility management apparatus, comprising:

a second receiving module, configured to receive a cell change request message from a source base station when an inactive state or a light-connected state of a user equipment UE meets a cell change condition and determines a target base station of a cell change, where the cell change request message at least carries a cell change mode identifier, and the cell change mode identifier indicates a cell change mode determined by the source base station;

A second switching module, configured to execute a switching of the UE according to the cell change mode indicated by the cell change request message;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

stopping a RAN area notification update (RAN area notification update);

stopping the measurement of the source base station;

the second switching module is configured to execute the switching of the UE according to the cell change mode indicated by the cell change request message, and includes:

when the cell changing mode is to keep the user plane link of the UE at the source base station, receiving a response message from the source base station, wherein the response message carries updated AS security information or NAS security information and transmits the updated AS security information or NAS security information to the UE;

21. The mobility management apparatus of claim 20, wherein the second handover module is configured to perform handover of the UE according to the cell change mode indicated by the cell change request message, and the handover module includes:

22. A mobility management method, comprising:

receiving a cell change command message issued by a source base station under the condition that User Equipment (UE) in an inactive state or a light-connected state meets a cell change condition and a target base station of a cell change is determined, wherein the cell change command message is used for indicating the UE to initiate the cell change to the target base station and at least carries a cell change mode identifier determined by the source base station;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

executing switching according to the cell switching mode indicated by the cell switching command message, wherein the switching comprises the following steps:

wherein the behavior of the corresponding item comprises one or more of:

stopping periodic monitoring of a physical channel for a source base station;

stopping RAN area update;

Stopping the measurement of the source base station;

the executing the switching according to the cell switching mode indicated by the cell switching command message comprises the following steps:

the cell changing mode is that when the user plane of the UE is linked to a source base station, after the UE is accessed to the target base station, if the AS security information or the NAS security information from the source base station and transmitted by the target base station is updated, the updated AS security information or the NAS security information is adopted to complete AS encryption and decryption, NAS encryption and decryption and integrity protection of data or signaling;

the executing the switching according to the cell switching mode indicated by the cell switching command message comprises:

23. The mobility management method according to claim 22, wherein performing handover according to the cell change mode indicated by the cell change command message comprises:

24. The mobility management method according to claim 22, wherein performing handover according to the cell change mode indicated by the cell change command message comprises:

wherein the maintaining of the state of the self at the source base station comprises: keeping a PDCP entity and a PDCP state, an RLC entity and an RLC state, AS security information and NAS security information of the base station in the source base station, and transferring the state of the base station to an IDLE state;

And the cell changing mode is to transfer the state of the UE in the source base station to an IDLE state after the switching process is finished when the user plane of the UE is transferred to the target base station.

25. The mobility management method according to claim 22, wherein performing handover according to the cell change mode indicated by the cell change command message comprises:

and the cell changing mode is that when the user plane of the UE is linked to a source base station, after the target base station is accessed, the PDCP entity, the RLC entity, the AS security information and the NAS security information of the source base station which are kept by the user plane are used for processing the operations of the PDCP layer and the RLC layer, the AS encryption and decryption, the NAS encryption and decryption and the integrity protection when receiving and sending data or signaling.

26. A mobility management apparatus, comprising:

a third receiving module, configured to receive a cell change command message issued by a source base station when a user equipment UE in an inactive state or a light-connected state meets a cell change condition and determines a target base station of a cell change, where the cell change command message is used to instruct the UE to initiate a cell change to the target base station, and the cell change command message at least carries a cell change mode identifier determined by the source base station;

the cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

the third handover module is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

wherein the behavior of the corresponding item comprises one or more of:

stopping periodic monitoring of a physical channel for a source base station;

stopping RAN area update;

stopping the measurement of the source base station;

the third switching module is configured to execute switching according to the cell change mode indicated by the cell change command message, and includes:

when the user plane of the UE is kept linked to a source base station, after AS security information or NAS security information which is transmitted by the target base station in a transparent mode and is from the source base station is updated, AS encryption and decryption, NAS encryption and decryption and integrity protection of data or signaling are completed by the updated AS security information or NAS security information;

and the cell changing mode is that when the user plane of the UE is transferred to be linked to a target base station:

and when the command message for changing the cell carries NAS security information, completing NAS security key negotiation according to the NAS security information, and transmitting the NAS security completion message to a core network connected with the target base station through the source base station when the key negotiation is successful.

27. The mobility management apparatus of claim 26, wherein the third handover module is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

28. The mobility management apparatus of claim 26, wherein the third handover module is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

29. The mobility management apparatus of claim 26, wherein the third handover module is configured to perform handover according to the cell change mode indicated by the cell change command message, and includes:

and the cell changing mode is that when the user plane of the UE is linked to a source base station, after the target base station is accessed, the PDCP entity, the RLC entity, the AS security information and the NAS security information of the source base station, which are kept by the UE, are used for processing the operations of the PDCP layer and the RLC layer, the AS encryption and decryption, the NAS encryption and decryption and the integrity protection when receiving and sending data or signaling.

30. The mobility management apparatus of claim 26,

the third switching module is configured to execute switching according to the cell change mode indicated by the cell change command message, and includes: and the cell changing mode is to transfer the state of the UE in the source base station to an IDLE state after the switching is finished when transferring the user plane of the UE to be linked to the target base station.

31. A mobility management apparatus comprising: a processor and a memory, wherein the memory stores computer-executable instructions that, when executed by the processor, implement a method comprising:

determining a cell change mode of User Equipment (UE) when the UE in an inactive state or a light-connected state meets the cell change condition and a target base station of a cell change is determined;

Under the condition that User Equipment (UE) in an inactive state or a light-connected state meets the condition of changing the cell and determines a target base station of the changed cell, receiving a request message of the changed cell from a source base station, wherein the request message of the changed cell at least carries a mode identifier of the changed cell, and the mode identifier of the changed cell represents the mode of the changed cell determined by the source base station;

the cell changing mode of the UE at least comprises one of the following modes: keeping the user plane of the UE linked to a source base station; transferring a user plane link of the UE to a target base station;

The cell change mode of the UE at least comprises one of the following modes:

keeping the user plane of the UE linked to a source base station;

transferring a user plane link of the UE to a target base station;

when the cell change mode is to maintain the user plane link of the UE to the source base station, the source base station is further configured to send a cell change command message to the UE, where the cell change command message is further configured to instruct the UE to stop one or more of the following behaviors:

stop a RAN area update (RAN area notification update);

stopping the measurement of the source base station;

the performing the handover of the UE according to the determined cell change mode further comprises:

When the cell changing mode is to transfer the user plane link of the UE to a target base station, receiving a cell changing response message from the target base station, and sending a cell changing command message to the UE, wherein the cell changing command message comprises a suspension instruction, and the suspension instruction is used for indicating the UE to save a source base station context after the cell changing is finished, and saving the source base station side context of the UE except for sending the cell changing command message to the UE;

when the cell change mode is to transfer the user plane link of the UE to a target base station, when the source base station and the target base station share the same core network node, sending a cell change response message to the source base station, wherein the cell change response message comprises AS security information established by the target base station for the UE and an NAS security information holding identifier, and the NAS security information holding identifier is used for informing the UE that the NAS security information of the source cell is reserved after the cell change is completed so AS to be reused at the target base station;