Patent Description:
Before sending an indication of an IP multimedia subsystem (IMS) voice over PS session to a user equipment (UE), an access and mobility management function physical device (AMF) needs to perform a UE capability match procedure in which the AMF sends a capability match request of the UE to the base station, namely the AMF needs to request the base station for checking whether the UE radio capability and base station capability match; and the AMF sends an indication of IMS voice over PS session to the UE after the UE radio capability match is determined.

However, according to the requirement of 3GPP SA3, the <NUM> base station needs to activate the access stratum security (AS security) of the UE when acquiring the UE radio capability from the UE. In the related art, if the UE does not have set up a user plane connection during the process of the UE being registered into the network, the base station may not set up an access stratum security context (AS security context) for the UE, and therefore, during the registration, the base station is unable to acquire the UE radio capability, that is, the base station is unable to determine whether the UE radio capability matches, and thus the AMF is unable to send the indication of the IMS voice over PS session during the registration, which results in the UE being unable to initiate IMS voice services.

Publication <NPL>, discloses a base station deciding to perform the radio capability without having an established AS security context, but the decision is not based on an indication received from an AMF.

Publication <NPL> discloses a standard way of proceeding between an AMF entity and a base station for the compatibility check required for the IMS voice service.

To solve the problems in the related art, embodiments of the present application provide methods for checking UE capability match, AMFs and base stations according to the independent claims.

Further detailed embodiments are presented in the dependent claims.

By the methods for checking the UE capability match, the AMFs, the base stations and the storage mediums according to the embodiments of the application, the problem that the base station does not respond to the UE capability match process requested by the AMF, which results in that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and thus the UE can normally obtain IMS voice service.

In order to more clearly illustrate solutions disclosed in the embodiments of the present application or the related art, the drawings used in the descriptions of the embodiments or the related art will be briefly described below. The drawings in the following description only show certain embodiments of the present application, and other drawings can be obtained according to the drawings without any creative effort for those skilled in the art.

In order to make the objects, solutions and advantages of the embodiments of the present application clearer, the solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and the described embodiments are some, but not all embodiments of the present application. All other embodiments, which can be obtained by a person skilled in the art without creative effort based on the embodiments of the present application, are within the scope of protection of the present application.

If an AMF requests more information related to UE radio capability support in order to set an IMS voice over PS Session Supported Indication, the AMF may send a UE radio capability match request to an NG-RAN, such as a base station. This procedure is typically performed during a registration process or when the UE does not receive a voice support match indication (belonging to a 5GMM context). Specifically, the process comprises the steps of: the AMF sends UE capability match request to the base station, after the UE capability match request is received by the base station, if the base station has not received UE radio capability before, then the base station requests UE to upload UE radio capability information; the UE sends RRC UE capability information including UE radio capability information to the base station,; the base station checks whether the UE radio capability is compatible with the network configuration that ensures continuity of IMS-originated voice call service. To decide the appropriate UE radio capability match response, the operator configures the base station to check whether the UE supports the specific capabilities required for IMS PS voice call continuity. If the base station requests radio capability from the UE, the base station also sends the UE radio capability to the AMF, and the AMF stores the UE radio capability.

However, according to the new requirement of 3GPP SA3, the <NUM> base station needs to activate AS security of the UE when acquiring UE radio capability from the UE. In the procedure of registering the UE in the network, if the UE does not set up the user plane connection, the base station may not set up AS security context for the UE, and therefore, during the registration process, the base station is unable to acquire the UE radio capability, that is, the base station is unable to determine whether the UE radio capability matches, and thus the AMF is unable to send the indication of the IMS voice over PS session during the registration process, which results in the UE being unable to initiate IMS voice services. In order to solve the above problems in the related art, embodiments of the present application propose a method for in which an indication of IMS voice over PS session is provided by an AMF to a UE during a registration procedure initiated by the UE, so as to avoid that the base station does not respond to the UE capability match process of the AMF, the AMF fails to issue an indication of the IMS voice over PS session during the registration process, thereby preventing the UE from failing to obtain an IMS voice service.

<FIG> shows a method for checking UE capability match according to an embodiment of the present application. As shown in <FIG>, the method includes at least the following steps:
Step <NUM>, determining to send a UE capability match request to a base station during a registration procedure initiated by the UE.

During the registration procedure initiated by the UE, since the AMF requests more information related to the UE radio capability support in order to set the IMS voice over PS Session Supported Indication, the AMF may determine to send the UE radio capability match request to an NG-RAN, for example, a base station, to request the base station to check whether the UE radio capability is compatible with a network configuration that ensures continuity of IMS-originated voice call service.

Step <NUM>, sending a request for setting up a UE's access stratum (AS) security context to the base station, and sending the UE capability match request to the base station after it is determined that the base station completes setup of the AS security context.

After the AMF determines to send the UE capability match request to the base station, the AMF in the embodiment of the application firstly sends a request to the base station and firstly requests the base station to set up the UE's AS security context. After receiving the request for setting up the UE AS security context, the base station completes the setup of the UE AS security context. After determining that the base station completes the setup of the UE AS security context, the AMF requests the base station to execute a UE capability match procedure, namely the AMF sends a UE capability match request to the base station, namely the AMF needs to request the base station to check whether the UE radio capability and the base station capability match; after determining the UE radio capability match, the AMF sends an indication of IMS voice over PS session to the UE.

Step <NUM>, receiving a UE capability match acknowledgement returned from the base station.

After receiving the UE capability match request sent by the AMF, the base station checks whether the UE radio capability and the base station capacity match, and informs the AMF after it is determined that they match; then the AMF sends indication of IMS voice over PS session to the UE after learning that the UE radio capability matches.

The UE capability match acknowledgement is generated by the base station according to the UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines that the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained from the UE by the base station after the UE AS security context is set up.

In the method for checking UE capability match according to the embodiment of the present application, the AMF firstly requests the base station to set up the UE AS security context, and then requests the base station to execute the UE capability match process, and thus the problem that the base station does not respond to the UE capability match process requested by the AMF, which results in that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

On the basis of the above method embodiments, the determining, by the AMF, to send the UE capability match request to the base station includes:
acquiring UE's relevant information, and determining to send the UE capability match request after determining that the UE is to use an IMS voice service according to the UE's relevant information; the relevant information includes at least one of the following information: UE's usage setting information, UE's access network information, and UE's subscription information.

Correspondingly, the determining that the UE is to use the IMS voice service according to the UE's relevant information may include:.

Specifically, when the UE registers to the network, the AMF may determine that a UE capability match process is required to be performed according to at least one of the UE' usage setting information, the UE's access network information, and the UE's subscription information, for example:.

By the method for checking the UE capability match, the AMF requests the base station to set up the security context, then requests the base station to check whether the UE capability and the base station capability match, and the AMF receives the checking result of the UE capability match from the base station, so that problem that the base station does not respond to the UE capability match process of the AMF, which results in that the AMF fails to issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

<FIG> shows a method for checking UE capability match according to another embodiment of the present application. As shown in <FIG>, the method includes at least the following steps:
Step <NUM>, determining to send a UE capability match request to a base station during a registration procedure initiated by the UE.

Step <NUM>, sending the UE capability match request to the base station, where the UE capability match request carries indication information for indicating the base station to ignore a UE's access stratum (AS) security context.

In the embodiment of the application, the AMF sends the UE capability match request to the base station after determining to send the UE capability match request to the base station. Also, in the embodiment of the present application, the UE capability match request may carry indication information, where the indication information is used to indicate the base station to ignore indication information of the UE AS security context.

After receiving the UE capability match request carrying the indication information, the base station may request the UE for its radio capability, and check whether the UE radio capability and the base station capability match each other under the indication of the indication information and without setting up the UE AS security context. After it is determined the UE radio capability matches, the AMF sends an indication of IMS voice over PS session to the UE.

The UE capability match acknowledgement is generated by the base station according to UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines that the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained from the UE by the base station in case that the UE AS security context is ignored according to the indication information.

In the method for checking UE capability match according to the embodiment of the application, the AMF requests the base station to check whether the UE radio capability and the base station capability match, and the request carries an indication for ignoring the AS security, and thus the problem that the base station does not respond to the UE capability match process requested by the AMF, which causes that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

On the basis of the above method embodiments, the determining, by the AMF, to send the UE capability match request to the base station includes:
acquiring UE's relevant information, and determining to send the UE capability match request after determining that the terminal is to use an IMS voice service according to the UE's relevant information; the relevant information includes at least one of the following information: UE's usage setting information, UE's access network information, and UE's subscription information.

Correspondingly, the determining that the terminal is to use an IMS voice service according to the UE's relevant information may include:.

Specifically, when the UE is registered into the network, the AMF may determine that a UE capability match process is required to be performed according to at least one of the UE's usage setting information, the UE's access network information, and the UE's subscription information, for example:.

By the method for checking UE capability match according to the embodiment of the application, the AMF requests the base station to check whether the UE radio capability and the base station capacity match, the request carries an indication for ignoring the AS security, and the AMF receives the checking result of the UE capability match from the base station, and thus the problem that the base station does not respond to the UE capability match process of the AMF, which results in that the AMF fails to issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

<FIG> shows a method for checking UE capability match according to another embodiment of the present application. As shown in <FIG>, the method includes at least the following steps:
Step <NUM>, receiving a UE capability match request sent by an access and mobility management function physical device (AMF) during a registration procedure initiated by the UE, where the UE capability match request carries indication information for indicating a base station to ignore a UE AS security context.

During the registration procedure initiated by the UE, since the AMF requests more information related to the UE radio capability support in order to set the IMS voice over PS Session Supported Indication, the AMF may determine to send a UE radio capability match request to an NG-RAN, for example, a base station, to request the base station to check whether the UE radio capability is compatible with a network configuration that ensures continuity of IMS-originated voice call service.

In the embodiment of the present application, the AMF sends the UE capability match request to the base station after determining to send the UE capability match request to the base station, in addition, in the embodiment of the present application, the UE capability match request may carry indication information, where the indication information is used to indicate the base station to ignore indication information of the UE AS security context.

After receiving the UE capability match request carrying the indication information, the base station may request the UE for its radio capability, and check whether the UE radio capability and the base station capability match each other under the indication of the indication information and without setting up the UE AS security context. After it is determined that the UE radio capability matches, the AMF sends an indication of IMS voice over PS session to the UE.

Step <NUM>, returning a UE capability match acknowledgement to the AMF.

The UE capability match acknowledgement is generated by the base station according to the UE capability information, and the UE capability information is acquired from the UE by the base station in case that the UE AS security context is ignored according to the indication information.

The UE capability match acknowledgement is generated by the base station according to the UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines that the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained from the UE by the base station in case that the UE AS security context is ignored according to the indication information.

By the method for checking UE capability match according to the embodiment of the application, the AMF requests the base station to check whether the UE capability and the base station capacity match, and the request carries an indication for ignoring the AS security, thus the problem that the base station does not respond to the UE capability match process of the AMF, which causes that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

On the basis of the above method embodiments, the UE capability match request is sent after the AMF acquires the UE's relevant information and determines that the UE is to use an IMS voice service according to the UE's relevant information; the relevant information includes at least one of the following information: UE's usage setting information, UE's access network information, and UE's subscription information.

By the method for checking UE capability match according to the embodiment of the application, the AMF requests the base station to check whether the UE capability and the base station capacity match, the request carries an indication for ignoring the AS security, and the AMF receives the checking result of the UE capability match from the base station, and thus the problem that the base station does not respond to the UE capability match process of the AMF, which causes that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

<FIG> shows a method for checking UE capability match according to another embodiment of the present application. As shown in <FIG>, in the method, an AMF determines that a RAN is requested to set up an AS security context first, and the method specifically includes:.

Step <NUM>, after determining that the RAN completes setup of UE security context, initiating, by the AMF, a UE capability match process and sending a UE capability match request to the RAN;
the AMF sends a UE Capability Match Request to the RAN.

Step <NUM>, receiving, by the AMF, a UE capability match acknowledgement sent by the RAN;
the RAN requests radio capability from the UE, checks whether UE radio capability and base station capability match, and informs the AMF after matching is determined.

Step <NUM>, after determining that the UE capability matches, the AMF continuing the normal registration process.

The AMF sends an indication of IMS voice over PS session to the UE after learning that the UE radio capability matches.

<FIG> shows a method for checking UE capability match according to another embodiment of the present application. As shown in <FIG>, in the method, the AMF determines that UE AS security context is not set up, and the method specifically includes:.

During the registration process, the AMF determines that the UE needs to use the IMS voice according to the UE usage setting and/or the IMS APN subscribed by the UE.

Step <NUM>, when returning the result of UE capability match, only returning, by the RAN, whether checking the UE radio capability match is successful, without providing the obtained UE radio capability information to the AMF.

After receiving the indication, the RAN acquires the UE radio capability from the UE even if the UE AS security context is absent, checks whether the UE radio capability and the base station capacity match, and informs the AMF after matching is determined.

Step <NUM>, after determining the UE capability matches, continuing, by the AMF, the normal registration process.

After knowing the UE radio capability matches, the AMF sends an indication of IMS voice over PS session to the UE.

<FIG> is a schematic structural diagram of an AMF according to an embodiment of the present application. As shown in <FIG>, the AMF includes a first determining module <NUM>, a first processing module <NUM>, and a first receiving module <NUM>, where:.

Specifically, during the registration procedure initiated by the UE, since the AMF requests more information related to the UE radio capability support in order to set the IMS voice over PS Session Supported Indication, the AMF may determine, through the first determining module <NUM>, to send a UE radio capability match request to the NG-RAN, for example, the base station, to request the base station to check whether the UE radio capability is compatible with the network configuration that ensures the continuity of IMS-initiated voice call service.

After the first determining module <NUM> determines to send the UE capability match request to the base station, in the embodiment of the present application, the AMF firstly sends a request to the base station through the first processing module <NUM>, and firstly requests the base station to set up an UE access stratum security context (AS security context). After receiving the request for setting up the UE AS security context, the base station completes the setup of the UE AS security context. After the AMF determines that the base station sets up the UE AS security context, the AMF requests the base station to perform a UE capability match process, that is, the first processing module <NUM> sends the UE capability match request to the base station. The first receiving module <NUM> receives the UE capability match acknowledgement returned from the base station, and after determining the UE radio capability matches, sends an indication of IMS voice over PS session to the UE.

The UE capability match acknowledgement is generated by the base station according to the UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained from the UE by the base station after the UE AS security context is set up.

By the method for checking UE capability match according to the embodiment of the application, the AMF firstly requests the base station to set up the UE AS security context, and then requests the base station to perform the UE capability match process, and the problem that the base station does not respond to the UE capability match process of the AMF, which causes that the AMF fails to issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

<FIG> is a schematic structural diagram of an AMF according to another embodiment of the present application. As shown in <FIG>, the AMF includes a memory <NUM>, a processor <NUM>, and a program stored in the memory <NUM> and executable on the processor <NUM>, where the memory <NUM> and the processor <NUM> communicate with each other through a communication bus <NUM>, and the program, when executed on the processor <NUM>, causes the processor <NUM> to perform the following steps:.

On the basis of the above method embodiment, the determining to send the UE capability match request to the base station includes:.

On the basis of the above method embodiment, the determining that the UE is to use the IMS voice service according to the UE's relevant information includes:.

In addition, the computer program in the memory <NUM> may be implemented in the form of a software functional unit and may be stored in a computer readable storage medium when the computer program is sold or used as a stand-alone product. The solution of the present application or a part thereof which substantially contributes to the related art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: U-disk, mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk, compact disk, and various media capable of storing program codes.

The method flow related to the execution of the program by the processor <NUM> may specifically refer to the above method embodiments, and details are not repeated here.

<FIG> is a schematic structural diagram of an AMF according to still another embodiment of the present application. As shown in <FIG>, the AMF includes a second determining module <NUM>, a second processing module <NUM>, and a second receiving module <NUM>, where:.

Specifically, during the registration procedure initiated by the UE, since the AMF requests more information related to the UE radio capability support in order to set the IMS voice over PS Session Supported Indication, the AMF may determine to send a UE radio capability match request to the NG-RAN, for example, the base station, through the second determination module <NUM>, to request the base station to check whether the UE radio capability is compatible with a network configuration that ensures IMS-initiated voice call service continuity. After the second determining module <NUM> determines to send the UE capability match request to the base station, in the embodiment of the present application, the AMF sends the UE capability match request to the base station through the second processing module <NUM>. In addition, in the embodiment of the present application, the UE capability match request may carry indication information for indicating the base station to ignore the indication information of the UE AS security context. After the base station receives the UE capability match request carrying the indication information, under the indication of the indication information and without setting up the UE AS security context, the base station may request the UE for its radio capability, and check whether the UE radio capability and the base station capability match each other. The second receiving module <NUM> receives the UE capability match acknowledgement returned from the base station, and after determining that the UE radio capability matches, sends the indication of the IMS voice over PS session to the UE.

The UE capability match acknowledgement is generated by the base station according to UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained by the base station from the UE according to the indication information while ignoring the UE AS security context.

<FIG> is a schematic structural diagram of an AMF according to another embodiment of the present application. As shown in <FIG>, the AMF includes a memory <NUM>, a processor <NUM> and a program stored in the memory <NUM> and executable on the processor <NUM>, where the memory <NUM> and the processor <NUM> communicate with each other through a communication bus <NUM>, and the program, when executed on the processor <NUM>, causes the processor <NUM> to perform the following steps:.

In addition, the computer program in the memory <NUM> may be implemented in the form of a software functional unit and may be stored in a computer readable storage medium when the computer program is sold or used as a standalone product. Based on such understanding, the solution of the present application or a part thereof which substantially contributes to the related art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: U-disk, mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk, compact disk, and various media capable of storing program codes.

The processor <NUM> executes the method flow related to the program, which may refer to the above method embodiments specifically, and is not repeated here.

<FIG> is a schematic structural diagram of a base station according to an embodiment of the present application. As shown in <FIG>, the base station includes a third receiving module <NUM> and a sending module <NUM>, where:.

Specifically, after the AMF determines to send the UE capability match request to the base station, in the embodiment of the present application, the AMF sends the UE capability match request to the base station. In addition, in the embodiment of the present application, the UE capability match request may carry indication information for indicating the base station to ignore indication information of the UE AS security context. After the base station receives the UE capability match request carrying the indication information through the third receiving module <NUM>, under the indication of the indication information and without setting up the UE AS security context, the base station may request the UE for its radio capability, and check whether the UE radio capability and the base station capacity match each other. After determining that the UE radio capability matches, the AMF sends an indication of IMS voice over PS session to the UE. After receiving the UE capability match request sent by the AMF, the third receiving module <NUM> checks whether the UE radio capability and the base station capability match, and notifies the AMF through the sending module <NUM> after determining the UE radio capability matches; then the AMF sends indication of IMS voice over PS session to the UE after learning that the UE radio capability matches.

The UE capability match acknowledgement is generated by the base station according to UE capability information, specifically, the UE capability match acknowledgement is generated after the base station determines the UE radio capability and the base station capacity match each other. Further, the UE capability information is obtained by the base station from the UE in case that the UE access stratum security context is ignored according to the indication information.

By the method for checking UE capability match according to the embodiment of the application, the AMF requests the base station to check whether the UE capability and the base station capacity match, and the request carries an indication for ignoring the AS security, and the problem that the base station does not respond to the UE capability match process of the AMF, which causes that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and the UE can normally obtain IMS voice service.

<FIG> is a schematic structural diagram of a base station according to another embodiment of the present application. As shown in <FIG>, the terminal includes a memory <NUM>, a processor <NUM>, and a program stored in the memory <NUM> and executable by the processor <NUM>, where the memory <NUM> and the processor <NUM> communicate with each other through a communication bus <NUM>, and the program, when executed by the processor <NUM>, causes the processor <NUM> to perform the following steps:.

In the above method embodiment, the UE capability match request is sent after the AMF acquires the UE's relevant information and determines that the terminal is to use IMS voice service according to the UE's relevant information;
the relevant information includes at least one of the following information: UE's usage setting information, UE's access network information, and UE's subscription information. In the above method embodiment, the determining that the UE is to use the IMS voice service according to the UE's relevant information includes:.

Further, the computer program in the memory <NUM> may be implemented in the form of a software functional unit and stored in a computer readable storage medium when the computer program is sold or used as a separate product. Based on such understanding, the solution of the present application or a part thereof which substantially contributes to the related art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: U-disk, mobile hard disk, Read-Only Memory (ROM), Random Access Memory (RAM), magnetic disk, compact disk, and various media capable of storing program codes.

The method flow related to the execution of the program by the processor <NUM> may specifically refer to the above method embodiment, and is not repeated here.

The non-transitory computer-readable storage medium according to the embodiments of the present application is specifically configured to execute the process of the method for checking the UE capability match provided in the foregoing method embodiments, and specific functions and processes of the process may be referred to in the foregoing method embodiments, which are not repeated here.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the objective of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort. Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment may be implemented by software plus a necessary general hardware platform, and may also be implemented by hardware. Based on such understanding, the above solutions substantially or otherwise contributing to the related art may be embodied in the form of a software product, which may be stored in a computer-readable storage medium, such as ROM/RAM, magnetic disk, compact disk, etc., and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method according to the various embodiments or some parts of the embodiments.

Claim 1:
A method, performed by an access and mobility management function, AMF, for checking UE capability match, comprising:
determining (<NUM>) to send a UE capability match request to a base station during a registration procedure initiated by the UE;
sending (<NUM>) a request for setting up a UE's access stratum, AS, security context to the base station, and sending the UE capability match request to the base station after it is determined that the base station completes setup of the AS security context; and
receiving (<NUM>) a UE capability match acknowledgement returned from the base station;
wherein the UE capability match acknowledgement is generated by the base station according to UE capability information, and the UE capability information is acquired from the UE by the base station after the setup of the AS security context is completed.