Communication method and apparatus

Abstract

The present application provides a communication method and apparatus. The method comprises: a communication apparatus acquires first information in the process of registering to a first network, wherein the first information comprises an identifier of a first AMF in the first network; the communication apparatus acquires second information, wherein the second information is used for instructing the communication apparatus to enter a multi-connection state; and on the basis of the second information, the communication apparatus sends the first information to a second network in the process of registering to the second network, wherein the first information is used for a second AMF in the second network to determine the first AMF. According to the embodiments of the present application, in a multi-connection scenario, the communication apparatus can send the identifier of the first AMF to the second network in the process of registering to the second network, so that the second AMF can determine the first AMF on the basis of the identifier of the first AMF, and then establish a connection with the first AMF, thereby enabling the first AMF and the second AMF to collaboratively manage the mobility of the communication apparatus.

Description

Communication method and device

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 21, 2023, with application number 202311055110.3, and priority to the Chinese patent application with the invention name “Communication Method and Device”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communications, and more specifically, to a communication method and apparatus. Background Art

[0003] In multi-connection scenarios, terminal devices can access multiple different networks. For example, in dual connectivity, a terminal device can access two networks simultaneously. Currently, each network manages the terminal's mobility independently. This management approach may result in uncoordinated management of the terminal's mobility across the two networks. Therefore, how to enable coordinated management of the terminal's mobility across multiple networks in multi-connection scenarios is a challenge that needs to be addressed.

[0004] Summary of the Invention

[0005] The present application provides a communication method and apparatus for collaboratively managing the mobility of a terminal device by multiple networks in a multi-connection scenario.

[0006] In a first aspect, a communication method is provided, the method comprising:

[0007] During the process of registering with a first network, the communication device obtains first information, where the first information includes an identifier of a first access and mobility management network element in the first network; the communication device obtains second information, where the second information is used to indicate that the communication device enters a multi-connection state; and based on the second information, the communication device sends the first information to the second network during the process of registering with the second network, where the first information is used by the second access and mobility management network element in the second network to determine the first access and mobility management network element.

[0008] As an optional manner, the communication device sends the first information to the second network, which may also implicitly instruct the communication device to enter the multi-connection state. The communication device may be a terminal device or a chip in the terminal device.

[0009] According to an embodiment of the present application, in a multi-connection scenario, the terminal device can send the identifier of the first access and mobility management network element in the first network to the second network during the process of registering to the second network, so that the access and mobility management network element in the second network can determine the first access and mobility management network element in the first network based on the identifier of the first access and mobility management network element, and then establish a connection with the first access and mobility management network element, thereby realizing the collaborative management of the mobility of the terminal device by the first access and mobility management network element and the second access and mobility management network element in the second network.

[0010] In combination with the first aspect, in some implementations of the first aspect, the first information is the 5G-Globally Unique Temporary Identifier (GUTI) corresponding to the first access and mobility management network element, or the Globally Unique AMF Identifier (GUAMI) corresponding to the first access and mobility management network element.

[0011] It is understood that 5G-GUTI includes GUAMI and 5G-Temporary Mobile User Identity (TMSI). Furthermore, GUAMI includes Mobile Country Code (MCC), Mobile Network Code (MNC) and AMF ID. Among them, 5G-TMSI is the temporary identifier of the terminal device. MCC and MNC are the identifiers of the Public Land Mobile Network (PLMN), and AMF ID is the identifier of AMF.

[0012] In conjunction with the first aspect, in certain implementations of the first aspect, the communication device, during registration with the first network, obtaining the first information includes:

[0013] During the process of registering to the first network, the communication device receives a registration acceptance message from the first access and mobility management network element, where the registration acceptance message includes the 5G-GUTI corresponding to the first access and mobility management network element.

[0014] With reference to the first aspect, in certain implementations of the first aspect, the registration accept message further includes a GUAMI corresponding to the first access and mobility management network element.

[0015] In conjunction with the first aspect, in some implementations of the first aspect, the communication device acquiring the second information includes:

[0016] The communication device obtains the second information based on an operation instruction of a user; or, the communication device obtains the second information from the first access and mobility management network element.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0018] The communication device sends the second information to the second network.

[0019] In combination with the first aspect, in certain implementations of the first aspect, when the communication device enters the mobility restriction area of ​​the first network but does not enter the mobility restriction area of ​​the second network, the method further includes:

[0020] The communication device receives a deregistration request message from the second access and mobility management network element;

[0021] The communication device sends a deregistration acceptance message to the second access and mobility management network element according to the deregistration request message, and releases the signal connection with the access network device in the second network.

[0022] In combination with the first aspect, in some implementations of the first aspect, the deregistration request message further includes reason information for deregistering the communication device, and the reason information indicates that the communication device enters a mobility restriction area of ​​the first network.

[0023] In a second aspect, a communication method is provided. The method is applied to a scenario where a communication device accesses a first network and a second network, the first network including a first network element, and the method includes:

[0024] The first network element determines whether the communication device enters the mobility restriction area of ​​the first network; when the communication device enters the mobility restriction area of ​​the first network, the first network element sends third information to the second network, where the third information is used to instruct the second network to stop providing services to the communication device, and the state of the communication device in the first network is a state of stopping obtaining services.

[0025] According to an embodiment of the present application, in a multi-connection (for example, dual-connection) scenario, if a terminal device enters the mobility restriction area of ​​the first network, the first network element in the first network sends a third information to the second network to instruct the second network to stop providing services to the terminal device, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0026] In the present application, as a method, a device in the second network can deregister the terminal device based on the third information. The terminal device is also in a deregistered state in the first network, so that the mobility restrictions on the terminal device in the first network and the second network are consistent. Exemplarily, the device in the second network can send a deregistration request message to the terminal device. Optionally, the deregistration request message can also include a reason for deregistering the terminal device, which is that the terminal device enters the mobility restriction area of ​​the first network. It can be understood that in the process of deregistering the terminal device, the device in the second network can release the session with the terminal device and stop information interaction with the terminal device.

[0027] Alternatively, the terminal device can remain registered. The device in the second network can restrict the terminal device from establishing sessions and accessing related services based on the third information. The device in the second network can release all sessions of the terminal device based on the third information. The device in the second network can stop exchanging information other than mobility-related information with the terminal device based on the third information.

[0028] In addition, optionally, the device in the second network can also update the mobility restriction area list of the terminal device in the second network based on the third information, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, which is the area where the terminal device is currently located.

[0029] In conjunction with the second aspect, in certain implementations of the second aspect, the first network element is a first access and mobility management network element, and the method further includes:

[0030] The first network element receives second information and fourth information from a second access and mobility management network element in the second network, wherein the second information is used to indicate that the communication device is in a multi-connection state, and the fourth information includes an identifier of the second access and mobility management network element.

[0031] In combination with the second aspect, in some implementations of the second aspect, the fourth information is the 5G-GUTI corresponding to the second access and mobility management network element, or the GUAMI corresponding to the second access and mobility management network element.

[0032] In conjunction with the second aspect, in certain implementations of the second aspect, the first network element is a unified data management network element, and the method further includes:

[0033] During the process of the communication device registering to the first network, the first network element obtains first information from the first access and mobility management network element in the first network, and the first information includes the identifier of the first access and mobility management network element; during the process of the communication device registering to the second network, the first network element obtains second information and fourth information from the second access and mobility management network element in the second network, the second information is used to indicate that the communication device is in a multi-connection state, and the fourth information includes the identifier of the second access and mobility management network element.

[0034] In combination with the second aspect, in some implementations of the second aspect, the first information is the 5G-GUTI corresponding to the first access and mobility management network element, or the GUAMI corresponding to the first access and mobility management network element; the fourth information is the 5G-GUTI corresponding to the second access and mobility management network element, or the GUAMI corresponding to the second access and mobility management network element.

[0035] In combination with the second aspect, in certain implementations of the second aspect, the first network is the home network of the terminal device, and the second network is the visited network of the terminal device; or, the first network is the first visited network of the terminal device, and the second network is the second visited network of the terminal device.

[0036] It is understandable that the first visited network is a primary visited network, and the second visited network is a secondary visited network. As a method, the home network can configure the priority of the visited network, and the priority of the primary visited network is higher than that of the secondary visited network.

[0037] As a case, if the first network is the home network and the second network is the roaming network, since the contract data of the terminal device is in the first network and the second network is the network accessed by the terminal device using the contract data of the first network, the contract data of the terminal device includes the contract service of the terminal device. Therefore, when the first network and the second network jointly manage the mobility of the terminal device, it is more reasonable to give priority to the first network (that is, if the terminal device enters the mobility restriction area of ​​the first network but does not enter the mobility restriction area of ​​the second network, the terminal device will stop obtaining the contract service in the second network).

[0038] In another case, if the first network is the primary visited network and the second network is the secondary visited network, the priority of the primary visited network is higher than that of the secondary visited network. Therefore, when the first network and the second network jointly manage the mobility of the terminal device, it is more reasonable to give priority to the first network.

[0039] In conjunction with the second aspect, in certain implementations of the second aspect, the third information is used to indicate one or more of the following:

[0040] Instruct the terminal device to enter the mobility restriction area of ​​the first network; instruct the terminal device to be deregistered; instruct the release of all sessions of the terminal device; instruct the cessation of information interaction with the terminal device; instruct the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, and the first area is the area where the terminal device is located.

[0041] In conjunction with the second aspect, in some implementations of the second aspect, the first network element is a first access and mobility management network element; and the first network element determines whether the terminal device enters the mobility restriction area of ​​the first network, including:

[0042] The first network element receives a mobility registration update request message from the terminal device; and the first network element determines whether the terminal device enters a mobility restriction area of ​​the first network according to the mobility registration update request message.

[0043] The first network element sending the third information to the second network includes:

[0044] The first network element sends the third information to a second access and mobility management network element in the second network.

[0045] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0046] The first network element obtains first configuration information, and the first configuration information is used to instruct the first network element: if the terminal device enters the mobility restriction area of ​​the first network, the first network element sends the third information to the second access and mobility management network element; or, the first network element receives a first subscription message from the second access and mobility management network element, and the first subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the first network, the first network element sends the third information to the second access and mobility management network element; or, the first network element receives first policy update information from the first policy control network element, and updates the local policy of the first network element according to the first policy update information. After the update, the local policy of the first network element is: if the terminal device enters the mobility restriction area of ​​the first network, the first network element sends the third information to the second access and mobility management network element; wherein, the first network includes the first policy control network element.

[0047] In conjunction with the second aspect, in some implementations of the second aspect, the first network element is a unified data management network element; and the first network element determines whether the terminal device enters the mobility restriction area of ​​the first network, including:

[0048] The first network element receives a notification message from a first access and mobility management network element, wherein the notification message indicates that the terminal device enters the mobility restriction area of ​​the first network; the first network element determines, based on the notification message, that the terminal device enters the mobility restriction area of ​​the first network.

[0049] The first network element sending third information to the second network includes:

[0050] The first network element sends the third information to a second access and mobility management network element in the second network.

[0051] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0052] The first network element sends a first subscription message to the first access and mobility management network element, and the first subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; or, the first network element sends a first indication message to the first policy control network element, and the first indication message is used to instruct the first policy control network element to update the local policy of the first access and mobility management network element. After the update, the local policy of the first access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element, and the first network includes the first policy control network element.

[0053] In conjunction with the second aspect, in some implementations of the second aspect, the first network element is a first policy control network element; and the first network element determines whether the terminal device enters the mobility restriction area of ​​the first network, including:

[0054] The first network element receives a notification message from a first access and mobility management network element, wherein the notification message indicates that the terminal device enters the mobility restriction area of ​​the first network; the first network element determines, based on the notification message, that the terminal device enters the mobility restriction area of ​​the first network.

[0055] The first network element sending third information to the second network includes:

[0056] The first network element sends the third information to a second policy control network element in the second network.

[0057] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0058] The first network element sends a first subscription message to the first access and mobility management network element, and the first subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; or, the first network element sends first policy update information to the first access and mobility management network element, and the first policy update information is used to update the local policy of the first access and mobility management network element. After the update, the local policy of the first access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element.

[0059] In combination with the second aspect, in some implementations of the second aspect, the first network element determining whether the terminal device enters the mobility restriction area of ​​the first network includes:

[0060] The first network element receives fifth information from the second network, where the fifth information indicates that the terminal device has entered the mobility restriction area of ​​the second network; the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the fifth information.

[0061] In combination with the second aspect, in some implementations of the second aspect, the method further includes: when the terminal device does not enter the mobility restriction area of ​​the first network, the first network element sends sixth information to the second network, where the sixth information is used to indicate any one of the following:

[0062] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located.

[0063] According to an embodiment of the present application, in a multi-connection scenario, if the terminal device enters the mobility restriction area of ​​the second network, the first network element obtains the fifth information from the second network and sends the sixth information to the second network, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0064] Specifically, if the terminal device enters the mobility restriction area of ​​the second network but does not enter the mobility restriction area of ​​the first network, the devices in the second network can serve the terminal device, and the devices in the first network can also serve the terminal device, so that the mobility restrictions of the terminal device in the first network and the second network remain consistent. In other words, neither the first network nor the second network restricts the mobility of the terminal device.

[0065] In conjunction with the second aspect, in certain implementations of the second aspect, the first network element is a first access and mobility management network element; and the first network element receives fifth information from the second network, including:

[0066] The first network element receives the fifth information from a second access and mobility management network element of a second network.

[0067] The first network element sending sixth information to the second network includes:

[0068] The first network element sends the sixth information to the second access and mobility management network element.

[0069] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0070] The first network element sends a second subscription message to the second access and mobility management network element, and the second subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element.

[0071] With reference to the second aspect, in certain implementations of the second aspect, the first network element is a unified data management network element; and the first network element receives fifth information from the second network, including:

[0072] The first network element receives the fifth information from a second access and mobility management network element of the second network.

[0073] The first network element determining, according to the fifth information, whether the terminal device enters a mobility restriction area of ​​the first network includes:

[0074] The first network element sends a query message to the first access and mobility management network element based on the fifth information, and the query message is used to query whether the terminal device has entered the mobility restriction area of ​​the first network; the first network element receives a response message to the query message from the first access and mobility management network element; the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the response message. Alternatively, the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on whether a message related to the mobility update of the terminal device is received from the first access and mobility management network element. In other words, the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on whether a notification message is received from the first access and mobility management network element, and the notification message indicates that the terminal device has entered the mobility restriction area of ​​the first network.

[0075] The first network element sending sixth information to the second network includes:

[0076] The first network element sends sixth information to the second access and mobility management network element.

[0077] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0078] The first network element sends a second subscription message to the second access and mobility management network element, and the second subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element; or, the first network element sends a second indication message to the second policy control network element, and the second indication message is used to instruct the second policy control network element to update the local policy of the second access and mobility management network element. After the update, the local policy of the second access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element.

[0079] With reference to the second aspect, in certain implementations of the second aspect, the first network element is a first policy control network element; and the first network element receives fifth information from the second network, including:

[0080] The first network element receives the fifth information from a second policy control network element of the second network.

[0081] The first network element determining, according to the fifth information, whether the terminal device enters a mobility restriction area of ​​the first network includes:

[0082] The first network element sends a query message to the first access and mobility management network element based on the fifth information, and the query message is used to query whether the terminal device has entered the mobility restriction area of ​​the first network; the first network element receives a response message to the query message from the first access and mobility management network element; the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the response message. Alternatively, the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on whether a message related to the mobility update of the terminal device is received from the first access and mobility management network element. In other words, the first network element determines whether the terminal device has entered the mobility restriction area of ​​the first network based on whether a notification message is received from the first access and mobility management network element, and the notification message indicates that the terminal device has entered the mobility restriction area of ​​the first network.

[0083] The first network element sending sixth information to the second network includes:

[0084] The first network element sends sixth information to the second policy control network element.

[0085] In a third aspect, a communication method is provided, the method being applied to a scenario in which a terminal device accesses a first network and a second network, the first network including a first access and mobility management network element and a first network element, the method comprising:

[0086] The first access and mobility management network element receives a mobility registration update request message of the terminal device; the first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network based on the mobility registration update request message; if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends a notification message to the first network element, and the notification message indicates that the terminal device enters the mobility restriction area of ​​the first network.

[0087] According to an embodiment of the present application, when a terminal device enters a mobility restricted area of ​​a first network, the first access and mobility management network element sends a notification message to the first network element, so that the first network element can be informed that the terminal device enters the mobility restricted area of ​​the first network, enabling the first network element to manage the mobility of the terminal device.

[0088] In combination with the third aspect, in certain implementations of the third aspect, the first network is the home network of the terminal device, and the second network is the visited network of the terminal device; or, the first network is the first visited network of the terminal device, and the second network is the second visited network of the terminal device.

[0089] In conjunction with the third aspect, in certain implementations of the third aspect, the method further includes:

[0090] The first access and mobility management network element obtains first configuration information, and the first configuration information is used to instruct the first access and mobility management network element: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; or, the first access and mobility management network element receives a first subscription message from the first network element, and the first subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; or, the first access and mobility management network element receives first policy update information from the first policy control network element, and updates the local policy of the first access and mobility management network element according to the first policy update information. After the update, the local policy of the first network element is: if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; wherein, the first network includes the first policy control network element.

[0091] In combination with the third aspect, in certain implementations of the third aspect, when the terminal device enters the mobility restriction area of ​​the second network, the method further includes:

[0092] The first access and mobility management network element receives a query message from the first network element, where the query message is used to query whether the terminal device has entered the mobility restriction area of ​​the first network; the first access and mobility management network element sends a response message to the first network element based on the query message, where the response message includes indication information that the terminal device has not entered the mobility restriction area of ​​the first network, and / or information of the first area; wherein the first area is the area where the terminal device is located.

[0093] In combination with the third aspect, in certain implementations of the third aspect, the first network element is a unified data management network element; or, the first network element is a first policy control network element.

[0094] In a fourth aspect, a communication method is provided, the method being applied to a scenario in which a terminal device accesses a first network and a second network, the first network including a first network element, and the second network including a second access and mobility management network element, the method comprising:

[0095] When the terminal device enters the mobility restriction area of ​​the first network, the second access and mobility management network element receives third information from the first network element, where the third information is used to instruct the second network to stop providing services to the terminal device; the second access and mobility management network element stops providing services to the terminal device based on the third information.

[0096] According to an embodiment of the present application, when a terminal device enters the mobility restriction area of ​​the first network, the second access and mobility management network element can stop providing services to the terminal device, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0097] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the first network element is a first access and mobility management network element, and the method further includes:

[0098] The second access and mobility management network element receives first information and second information from the communication device, where the first information includes an identifier of the first access and mobility management network element, and the second information is used to indicate that the communication device is in a multi-connection state; the second access and mobility management network element sends the second information and fourth information to the first access and mobility management network element based on the first information, where the fourth information includes the identifier of the second access and mobility management network element.

[0099] In combination with the fourth aspect, in some implementations of the fourth aspect, the first information is the 5G-GUTI corresponding to the first access and mobility management network element, or the GUAMI corresponding to the first access and mobility management network element; the fourth information is the 5G-GUTI corresponding to the second access and mobility management network element, or the GUAMI corresponding to the second access and mobility management network element.

[0100] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first network is the home network of the terminal device, and the second network is the visited network of the terminal device; or, the first network is the first visited network of the terminal device, and the second network is the second visited network of the terminal device.

[0101] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the third information is used to indicate one or more of the following:

[0102] Instruct the terminal device to enter the mobility restriction area of ​​the first network; instruct the terminal device to be deregistered; instruct the release of all sessions of the terminal device; instruct the cessation of information interaction with the terminal device; instruct the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, and the first area is the area where the terminal device is located.

[0103] In combination with the fourth aspect, in certain implementations of the fourth aspect, the second access and mobility management network element stopping providing services to the terminal device according to the third information includes:

[0104] The second access and mobility management network element sends a deregistration request message to the terminal device according to the third information, where the deregistration request message is used to deregister the terminal device.

[0105] In combination with the fourth aspect, in some implementations of the fourth aspect, the deregistration request message also includes a reason for deregistering the terminal device, and the reason is that the terminal device enters a mobility restriction area of ​​the first network.

[0106] In combination with the fourth aspect, in certain implementations of the fourth aspect, the second access and mobility management network element stopping providing services to the terminal device according to the third information includes:

[0107] The second access and mobility management network element releases all sessions of the terminal device according to the third information.

[0108] Alternatively, the terminal device can remain registered. The second access and mobility management network element can restrict the terminal device from establishing a session and accessing related services based on the third information. The second access and mobility management network element can also stop exchanging information other than mobility-related information with the terminal device based on the third information.

[0109] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the method further includes:

[0110] The second access and mobility management network element updates the mobility restriction area list of the terminal device in the second network according to the third information, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area.

[0111] According to an embodiment of the present application, when a terminal device enters a mobility restriction area of ​​a first network, the second access and mobility management network element can update the mobility restriction area list of the terminal device in the second network, so that when the terminal device subsequently enters the first area, the second access and mobility management network element can directly stop providing services to the terminal device, thereby reducing signaling interaction and reducing overhead.

[0112] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first network element is a first access and mobility management network element; or, the first network element is a unified data management network element.

[0113] Alternatively, the first network element is a first policy control network element, and the second access and mobility management network element receives the third information from the first network element, including: the second access and mobility management network element receives the third information from the first network element through the second policy control network element in the second network.

[0114] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the method further includes:

[0115] The second access and mobility management network element receives a mobility registration update request message from the terminal device; the second access and mobility management network element determines, based on the mobility registration update request message, whether the terminal device enters the mobility restriction area of ​​the second network; if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends fifth information to the first network element, where the fifth information indicates that the terminal device enters the mobility restriction area of ​​the second network; and the second access and mobility management network element receives sixth information from the first network element, where the sixth information indicates any one of the following:

[0116] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located.

[0117] The second access and mobility management network element provides a service to the terminal device according to the sixth information. For example, the second access and mobility management network element may accept a mobility registration update request from the terminal device.

[0118] According to an embodiment of the present application, when a terminal device enters a mobility restriction area of ​​a second network, if the terminal device has not entered a mobility restriction area of ​​a first network, the second access and mobility management network element can provide services to the terminal device, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device.

[0119] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the method further includes:

[0120] The second access and mobility management network element updates the mobility restriction area list of the terminal device in the second network according to the sixth information, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area.

[0121] According to an embodiment of the present application, when a terminal device enters the mobility restriction area of ​​the second network but does not enter the mobility restriction area of ​​the first network, the second access and mobility management network element can update the mobility restriction area list of the terminal device in the second network, so that when the terminal device subsequently enters the first area, the second access and mobility management network element can directly accept the mobility registration update of the terminal device, reducing signaling interaction and reducing overhead.

[0122] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the first network element is a first access and mobility management network element or a unified data management network element, and the method further includes:

[0123] The second access and mobility management network element obtains second configuration information, and the second configuration information is used to instruct the second access and mobility management network element: if the terminal device enters the mobility restriction area of ​​the second network, send the fifth information to the first network element; or, the second access and mobility management network element receives a second subscription message from the first network element, and the second subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element; or, the second access and mobility management network element receives second policy update information from the second policy control network element, and updates the local policy of the second access and mobility management network element according to the second policy update indication information. After the update, the local policy of the second access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element, and the second network includes the second policy control network element.

[0124] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the first network element is a first policy control network element; and the second access and mobility management network element sends fifth information to the first network element, including:

[0125] The second access and mobility management network element sends the fifth information to the first network element through a second policy control network element in the second network.

[0126] The second access and mobility management network element receives the sixth information from the first network element, including: the second access and mobility management network element receives the sixth information from the first network element through the second policy control network element.

[0127] In conjunction with the fourth aspect, in certain implementations of the fourth aspect, the method further includes:

[0128] The second access and mobility management network element obtains second configuration information, and the second configuration information is used to instruct the second access and mobility management network element: if the terminal device enters the mobility restriction area of ​​the second network, send the fifth information to the second policy control network element; or, the second access and mobility management network element receives a second subscription message from the second policy control network element, and the second subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the second policy control network element; or, the second access and mobility management network element receives second policy update information from the second policy control network element, and updates the local policy of the second access and mobility management network element according to the policy update indication information. After the update, the local policy of the second access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the second policy control network element.

[0129] In a fifth aspect, a communication method is provided, the method being applied to a scenario in which a terminal device accesses a first network and a second network, the first network including a first policy control network element, and the second network including a second policy control network element and a second access and mobility management network element; when the terminal device enters a mobility restricted area of ​​the first network, the method including:

[0130] The second policy control network element receives third information from the first policy control network element, where the third information is used to instruct the second network to stop providing services to the terminal device; and the second policy control network element sends the third information to the second access and mobility management network element.

[0131] According to an embodiment of the present application, when a terminal device enters the mobility restriction area of ​​the first network, the second policy control network element can obtain third information from the first network and send the third information to the second access and mobility management network element, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0132] In combination with the fifth aspect, in certain implementations of the fifth aspect, the first network is the home network of the terminal device, and the second network is the visited network of the terminal device; or, the first network is the first visited network of the terminal device, and the second network is the second visited network of the terminal device.

[0133] In conjunction with the fifth aspect, in certain implementations of the fifth aspect, the third information is used to indicate one or more of the following:

[0134] Instruct the terminal device to enter the mobility restriction area of ​​the first network; instruct the terminal device to be deregistered; instruct the release of all sessions of the terminal device; instruct the cessation of information interaction with the terminal device; instruct the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, and the first area is the area where the terminal device is located.

[0135] In combination with the fifth aspect, in certain implementations of the fifth aspect, when the terminal device enters the mobility restriction area of ​​the second network, the method includes:

[0136] The second policy control network element receives fifth information from the second access and mobility management network element, where the fifth information indicates that the terminal device has entered the mobility restriction area of ​​the second network; the second policy control network element sends the fifth information to the first policy control network element; and the second policy control network element receives sixth information from the first policy control network element, where the sixth information indicates one or more of the following:

[0137] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located.

[0138] The second policy control network element sends the sixth information to the second access and mobility management network element.

[0139] According to an embodiment of the present application, when a terminal device enters the mobility restriction area of ​​the second network, the second policy control network element can send fifth information to the first network and obtain sixth information from the first network, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0140] In conjunction with the fifth aspect, in certain implementations of the fifth aspect, the method further includes:

[0141] The second policy control network element sends a second subscription message to the second access and mobility management network element, and the second subscription message is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the second policy control network element; or, the second policy control network element sends a second indication message to the second access and mobility management network element, and the second indication message is used to update the local policy of the second access and mobility management network element. After the update, the local policy of the second access and mobility management network element is: if the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the second policy control network element.

[0142] In a sixth aspect, a communication method is provided, the method being applied to a scenario in which a terminal device accesses a first network and a second network, the first network including a first access and mobility management network element, and the second network including a second access and mobility management network element, the method comprising:

[0143] The first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network; if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends third information to the second access and mobility management network element, and the third information is used to instruct the second network to stop providing services to the terminal device; the second access and mobility management network element stops providing services to the terminal device based on the third information; and the first access and mobility management network element stops providing services to the terminal device.

[0144] According to an embodiment of the present application, in a multi-connection (for example, dual connection) scenario, if the terminal device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends a third message to the second access and mobility management network element, the second access and mobility management network element stops serving the terminal device, and the first access and mobility management network element also stops serving the terminal device, thereby enabling the first network and the second network to collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device by the first network and the second network remain consistent.

[0145] In combination with the sixth aspect, in certain implementations of the sixth aspect, the first network is the home network of the terminal device, and the second network is the visited network of the terminal device; or, the first network is the first visited network of the terminal device, and the second network is the second visited network of the terminal device.

[0146] In conjunction with the sixth aspect, in certain implementations of the sixth aspect, the third information is used to indicate one or more of the following:

[0147] Instruct the terminal device to enter the mobility restriction area of ​​the first network; instruct the terminal device to be deregistered; instruct the release of all sessions of the terminal device; instruct the cessation of information interaction with the terminal device; instruct the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, and the first area is the area where the terminal device is located.

[0148] In combination with the sixth aspect, in certain implementations of the sixth aspect, the second access and mobility management network element stopping providing services to the terminal device according to the third information includes:

[0149] The second access and mobility management network element sends a deregistration request message to the terminal device according to the third information, where the deregistration request message is used to deregister the terminal device.

[0150] In combination with the sixth aspect, in some implementations of the sixth aspect, the deregistration request message also includes a reason for deregistering the terminal device, and the reason is that the terminal device enters a mobility restriction area of ​​the first network.

[0151] In combination with the sixth aspect, in certain implementations of the sixth aspect, the second access and mobility management network element stopping providing services to the terminal device according to the third information includes:

[0152] The second access and mobility management network element releases all sessions of the terminal device according to the third information.

[0153] In conjunction with the sixth aspect, in certain implementations of the sixth aspect, the method further includes:

[0154] The second access and mobility management network element updates the mobility restriction area list of the terminal device in the second network according to the third information, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area.

[0155] According to an embodiment of the present application, when a terminal device enters a mobility restriction area of ​​a first network, the second access and mobility management network element can update the mobility restriction area list of the terminal device in the second network, so that when the terminal device subsequently enters the first area, the second access and mobility management network element can directly stop providing services to the terminal device, thereby reducing signaling interaction and reducing overhead.

[0156] In combination with the sixth aspect, in some implementations of the sixth aspect, the first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network, including:

[0157] The first access and mobility management network element receives a mobility registration update request message from the terminal device; the first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network based on the mobility registration update request message.

[0158] In combination with the sixth aspect, in some implementations of the sixth aspect, the first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network, including:

[0159] The second access and mobility management network element receives a mobility registration update request message from the terminal device; the second access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the second network based on the mobility registration update request message; when the terminal device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends fifth information to the first access and mobility management network element, and the fifth information indicates that the terminal device enters the mobility restriction area of ​​the second network; the first access and mobility management network element determines whether the terminal device enters the mobility restriction area of ​​the first network based on the fifth information.

[0160] In combination with the sixth aspect, in some implementations of the sixth aspect, when the terminal device does not enter the mobility restricted area of ​​the first network, the first access and mobility management network element sends sixth information to the second access and mobility management network element, where the sixth information is used to indicate any one of the following:

[0161] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located.

[0162] The second access and mobility management network element provides a service to the terminal device according to the sixth information. For example, the second access and mobility management network element may accept a mobility registration update request from the terminal device.

[0163] In conjunction with the sixth aspect, in certain implementations of the sixth aspect, the method further includes:

[0164] The second access and mobility management network element updates the mobility restriction area list of the terminal device in the second network according to the sixth information, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area.

[0165] According to an embodiment of the present application, when a terminal device enters the mobility restriction area of ​​the second network but does not enter the mobility restriction area of ​​the first network, the second access and mobility management network element can update the mobility restriction area list of the terminal device in the second network, so that when the terminal device subsequently enters the first area, the second access and mobility management network element can directly accept the mobility registration update of the terminal device, reducing signaling interaction and reducing overhead.

[0166] In the seventh aspect, a communication device is provided. In one possible implementation, the communication device may include a module or unit corresponding to each of the methods / operations / steps / actions described in any one of the first to fifth aspects. The module or unit may be a hardware circuit, software, or a combination of hardware circuit and software.

[0167] In an eighth aspect, a communication device is provided, comprising a communication interface and a processor, wherein the communication interface is used to output and / or input signals, and the processor is used to execute a computer program or instruction stored in a memory, so that the communication device executes the method described in any one of the first to fifth aspects.

[0168] Optionally, the memory may be included in the communication device. As one approach, the memory may be provided separately from the processor; as another approach, the memory may be located in the processor and integrated with the processor.

[0169] Optionally, the memory may also be outside the communication device and coupled to the processor.

[0170] In a ninth aspect, a computer-readable storage medium is provided, comprising a computer program, which, when executed on a computer, enables the computer to execute the method in any one of the possible implementations of the first to fifth aspects.

[0171] In a tenth aspect, a chip or chip system is provided, the chip or chip system including a processing circuit and an input / output interface, the processing circuit being used to execute the method in any possible implementation of the first to fifth aspects.

[0172] In the eleventh aspect, a computer program product is provided, which includes: a computer program (also referred to as code, or instructions), which, when run, enables a computer to execute a method in any possible implementation of the first to fifth aspects.

[0173] In the twelfth aspect, a communication system is provided, which includes a first network and a second network, and a terminal device accesses the first network and the second network, the first network includes a first AMF, and the second network includes a second AMF, and the first AMF and the second AMF are used to execute the method in any possible implementation manner of the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0174] FIG1 shows a communication system to which the present application is applicable.

[0175] FIG2 is a flow chart of the method proposed in this application.

[0176] Figure 3 is a flow chart of the method in which the first network element is the first AMF.

[0177] FIG4 is a flow chart of a method in which the first network element is a UDM.

[0178] FIG5 is a schematic flow chart of a method in which the first network element is a first PCF.

[0179] FIG6 is a schematic block diagram of a communication device provided in this application.

[0180] FIG7 is another schematic block diagram of the communication device provided in this application. DETAILED DESCRIPTION

[0181] To make the objectives, technical solutions, and advantages of this application more clear, the present application will be further described in detail below with reference to the accompanying drawings. The specific operating methods in the method embodiments can also be applied to the device embodiments or system embodiments. In the description of this application, unless otherwise specified, the meaning of "multiple" is two or more.

[0182] It is understood that the various numbers used in this application are merely for ease of description and are not intended to limit the scope of this application. The order of execution of the above-mentioned processes does not necessarily imply a specific order of execution. The order of execution of each process should be determined by its function and inherent logic.

[0183] The terms "first," "second," "third," "fourth," and various other terminology and designations in the specification and claims of this application and the accompanying drawings (if any) are used to distinguish similar objects and are not necessarily used to describe a particular order or sequential sequence. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to the process, method, product, or apparatus.

[0184] It can be understood that, in this application, “used to indicate” can include both direct indication and indirect indication.

[0185] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field will know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0186] The technical solutions provided in this application can be applied to various communication systems, such as: fifth generation (5G) mobile communication system or new radio (NR) system, long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, etc. The technical solutions provided in this application can also be applied to future communication systems, such as sixth generation (6G) mobile communication system. The technical solutions provided in this application can also be applied to device to device (D2D) communication, vehicle-to-everything (V2X) communication, machine to machine (M2M) communication, machine type communication (MTC), and Internet of Things (IoT) communication system or other communication systems.

[0187] Figure 1 (A) is a schematic diagram of a communication network architecture. The network architecture may include the following devices or network elements:

[0188] 1. User equipment (UE): Also known as terminal equipment, it includes various handheld devices with wireless communication capabilities, in-vehicle devices, wearable devices, computing devices, or other processing devices connected to a wireless modem, as well as various forms of terminals, mobile stations (MS), terminals, or soft terminals. Examples include water meters, electricity meters, and sensors.

[0189] 2. (Radio) access network (R)AN): Provides network access for authorized user devices in a specific area and can use transmission tunnels of different qualities based on the level of the user device and service requirements.

[0190] The RAN manages radio resources, provides access services to user equipment, and forwards control signals and user equipment data between the user equipment and the core network.

[0191] The access network equipment includes but is not limited to: the next generation node basestation (gNB) in the 5G system, the evolved node B (eNB) in the LTE system, the radio network controller (RNC), the node B (NB), the base station controller (BSC), the base transceiver station (BTS), the home evolved nodeB (or home node B, HNB), the base band unit (BBU), the transmission and receiving point (TRP), the transmitting point (TP), the small base station equipment (pico), the mobile switching center, or the network equipment in the future network, etc. It is understandable that the present application does not limit the specific type of access network equipment. In systems using different wireless access technologies, the names of devices with access network equipment functions may be different.

[0192] Optionally, in some deployments of access devices, the access device may include a centralized unit (CU) and a distributed unit (DU). In other deployments of access devices, the CU may be further divided into a CU-control plane (CP) and a CU-user plane (UP). In still other deployments of access devices, the access device may also be an open radio access network (ORAN) architecture. This application does not limit the specific deployment method of the access device.

[0193] 3. User plane function (UPF) network element: This element is used for packet routing and forwarding, as well as quality of service (QoS) processing for user plane data. User data can be connected to the data network (DN) through this element. In the embodiments of the present application, this element can be used to implement the functions of the user plane network element.

[0194] 4. DN: A network used to transmit data, such as a carrier's service network, the Internet, or a third-party service network.

[0195] 5. Authentication server function (AUSF) network element: mainly used for user authentication, etc.

[0196] 6. Access and mobility management function (AMF) network element: Mainly used for mobility management and access management. For example, it can be used to implement mobility restriction, initial registration of terminal devices, mobility registration update, deregistration, registration management, etc.

[0197] 7. Session management function (SMF) network element: mainly used for session management, network Internet protocol (IP) address allocation and management of terminal devices, selection and management of user plane functions, policy control and charging function interface endpoints, and downlink data notification.

[0198] 8. Policy control function (PCF) network element: A unified policy framework used to guide network behavior, providing policy rule information to network elements (such as AMF, SMF network elements, etc.) or terminal devices.

[0199] For example, PCF can provide access and mobility policy control services to AMF, which includes providing mobility-related policy rules to AMF and updating mobility-related policy rules.

[0200] 9. Network repository function (NRF) network element: used to store descriptions of network function entities and the services they provide, and to support functions such as service discovery and network element entity discovery.

[0201] 10. Network exposure function (NEF) network element: used to securely expose services and capabilities provided by the Third Generation Partnership Project (3GPP) network function to the outside world.

[0202] 11. Unified data management (UDM) network element: used for unified data management, 5G user data management, processing user identification, access authentication, registration, or mobility management, etc.

[0203] For example, UDM can perform security authentication in the mobility registration process of the terminal device, exchange contract data with AMF, update the context of the terminal device, etc.

[0204] 12. Application function (AF) network element: used for data routing affected by applications, accessing network open function network elements, and interacting with the policy framework for policy control.

[0205] 13. Network data analytics function (NWDAF): NWDAF can have at least one of the following functions:

[0206] Data collection, model training, model feedback, analysis result reasoning, analysis result feedback, etc.

[0207] In the above network architecture, the N2 interface is the interface between the RAN and AMF network elements, used for sending radio parameters and non-access stratum (NAS) signaling; the N3 interface is the interface between the RAN and UPF network elements, used for transmitting user plane data; the N4 interface is the interface between the SMF network element and the UPF network element, used for transmitting information such as service policies, tunnel identification information of the N3 connection, data cache indication information, and downlink data notification messages. The N6 interface is the interface between the DN network element and the UPF network element, used for transmitting user plane data.

[0208] It should be understood that the above-mentioned network architecture applied to the embodiment of the present application is only an example of the network architecture described from the perspective of the traditional point-to-point architecture and the service-oriented architecture. The network architecture applicable to the embodiment of the present application is not limited to this. Any network architecture that can realize the functions of the above-mentioned network elements is applicable to the embodiment of the present application.

[0209] It should be noted that the names of the various network elements and interfaces in this application are merely examples. This application does not exclude the possibility that the network elements may be renamed in the future, or that the functions of the network elements may be merged. As technology evolves, any device or network element that can implement the functions of the aforementioned network elements falls within the scope of protection of this application. Furthermore, the aforementioned network elements may also be referred to as entities, devices, apparatuses, functions, or modules, etc., and this application does not specifically limit these terms.

[0210] For ease of understanding, some terms in this application are explained below.

[0211] (1) Tracking area (TA)

[0212] A TA may include one or more cells.

[0213] (2)Register area (RA)

[0214] An RA may include one or more TAs, which may be included in a "TA list".

[0215] As an implementation manner, if the terminal device moves within the TA list allocated to the terminal device, the terminal device does not need to perform mobility registration update.

[0216] In other words, if the terminal device leaves the current registration area, the terminal device needs to initiate a mobility registration update and the AMF will allocate a new registration area.

[0217] (3) Mobility restrictions

[0218] Mobility restrictions on terminal devices are used to restrict UEs from accessing the network or obtaining services in a specific area. Mobility restrictions include the following:

[0219] a: Radio access type (RAT) restriction

[0220] RAT restriction is based on the granularity of the public land mobile network (PLMN). RAT restriction is used to specify the types of radio access allowed and not allowed for a particular PLMN.

[0221] b: forbidden area

[0222] The prohibited area is based on the TA granularity. In the prohibited area, the terminal device is not allowed to initiate communication to any network in the TA.

[0223] c: Service area restriction

[0224] In service area restrictions, two types of areas are defined: the allowed area and the non-allowed area. In the allowed area, the terminal device can communicate with the network. In the non-allowed area, no other communication is allowed between the terminal device and the network except for mobility-related data.

[0225] d: core network type restriction

[0226] The core network type restriction defines whether the UE can access the 5GC under a PLMN network and / or whether the UE can access the evolved packet core (EPC) network under a PLMN network.

[0227] (4) NR satellite access

[0228] Because satellite coverage is large, for low-orbit or high-orbit satellites, the satellites are constantly moving relative to the ground during their movement. Therefore, the satellite's coverage area is also mobile. During satellite movement, a satellite may cover one or more TAs simultaneously. When a UE accesses the core network via satellite, if at least one of the TAs covered by the satellite belongs to the UE's registration area, the UE does not need to perform a mobility registration update.

[0229] That is, when a satellite moves, it may broadcast one or more tracking area identities (TAIs). A terminal device may receive one or more TAIs. The terminal device is considered to be in a restricted mobility area only when all the TAs indicated by the TAIs broadcast by the satellite belong to the restricted mobility area. The terminal device is considered to be outside the restricted mobility area when at least one of the TAs indicated by all the TAIs broadcast by the satellite does not belong to the restricted mobility area.

[0230] Similarly, for service area restrictions, the terminal device is considered to be in a non-permitted area only when all TAs indicated by the satellite broadcast TAIs belong to the non-permitted area. The terminal device is considered not to be in a non-permitted area (or in a permitted area) when at least one TA among all TAs indicated by the satellite broadcast TAIs belongs to the permitted area.

[0231] (5) The home public land mobile network (H-PLMN) and the visit public land mobile network (V-PLMN) of the terminal device

[0232] The HPMN of the terminal device may also be referred to as the home network of the terminal device. In the embodiment of the present application, the HPMN of the terminal device may be understood as the PLMN where the subscription data of the terminal device is located.

[0233] The V-PLMN of the terminal device can also be called the visited network of the terminal device. In the embodiment of the present application, the V-PLMN of the terminal device can be understood as: the PLMN that the terminal device accesses using the subscription data roaming of the H-PLMN.

[0234] (6)Multiple connections

[0235] As shown in Figure 1 (B), multi-connectivity can be understood as a terminal device using the same subscription data to access multiple different networks through multiple 3GPP interfaces at the same time. It is understood that the architecture of Figure 1 (B) is only exemplary, and the terminal device can access two or more networks.

[0236] For example, a terminal device accesses an HPLMN through a subscription data and additionally selects a V-PLMN for roaming access, thereby realizing a dual-connectivity architecture for accessing two networks simultaneously.

[0237] For another example, the terminal device can access two V-PLMNs (respectively referred to as a first V-PLMN and a second V-PLMN), the first V-PLMN being a primary V-PLMN and the second V-PLMN being a secondary V-PLMN.

[0238] In addition, in this application, multi-connection can be further extended as follows:

[0239] 1: Support dual / multiple radio capability.

[0240] 2: Support dual (or multiple) 3GPP access technology (dual / multiple 3GPP RAT).

[0241] 3: Support dual (or multiple) steer capability.

[0242] 4: Support dual / multiple 3GPP access.

[0243] 5: Support dual / multiple 3GPP access type.

[0244] 6: Support dual / multiple registration.

[0245] 7: Support the same access type.

[0246] 8: Support the same access technology (same RAT).

[0247] 9: Support the same access network.

[0248] (7) Access type and access technology:

[0249] The 3GPP access network refers to an access network whose access type is a 3GPP access type (the access type may also be referred to as an access mode).

[0250] 3GPP access types include but are not limited to the following access technologies: LTE access technology (corresponding to 4G cellular network), NR access technology (corresponding to 5G cellular network), 3GPP-defined satellite access technology, or subsequently evolved cellular access technology; among them, the 3GPP-defined satellite access technology can also be subdivided into low-orbit satellite access technology, medium-orbit satellite access technology, and synchronous satellite access technology.

[0251] A non-3GPP access network refers to an access network whose access type is a non-3GPP access type.

[0252] Non-3GPP access types include, but are not limited to, the following access technologies: untrusted non-3GPP access technology (e.g., accessing the core network through a wireless access node purchased by an individual), trusted non-3GPP access technology (e.g., accessing the core network through a wireless access node deployed by an operator), wireline access technology, Institute of Electrical and Electronics Engineers (IEEE) 802.11 access technology, non-3GPP access technology connected via standalone non-public networks (NPN) (SNPN), Broadband Forum (BBF) access technology, cable access technology, etc. Specifically, the non-3GPP access type may be or may include access technologies such as wired, wireless fidelity (WiFi), Bluetooth, and ZigBee.

[0253] The technical issues addressed by this application are described below.

[0254] Taking dual connectivity in multi-connectivity as an example, a terminal device can access a first network and a second network. In an embodiment of the present application, in one case, the first network can be an HPLMN network, and the second network can be a V-PLMN network. In another case, the first network can be a first V-PLMN network, and the second network can be a second V-PLMN network.

[0255] Currently, in a multi-connection scenario, for mobility registration of a terminal device, the first network and the second network manage the mobility of the terminal device independently.

[0256] Due to the different deployment methods of different networks, the distribution of cells in different networks may vary. Furthermore, the distribution of tracking areas (TAs) in different networks may vary. Furthermore, for a terminal device, the registration area allocated to the terminal device in a first network may be different from the registration area allocated to the terminal device in a second network. Furthermore, the mobility restriction area of ​​the terminal device in the first network may be different from the mobility restriction area of ​​the terminal device in the second network.

[0257] Based on this, the different mobility restriction areas of the first network and the second network may lead to the following situations:

[0258] (1) The location of the terminal device is within the mobility restriction area of ​​the first network, but not within the mobility restriction area of ​​the second network.

[0259] (2) The location of the terminal device is not within the mobility restriction area of ​​the first network, but within the mobility restriction area of ​​the second network.

[0260] In addition, in a multi-connectivity (e.g., dual-connectivity) scenario, a terminal device can access Network #1 via satellite and Network #2 via terrestrial access network equipment. In this scenario, since a satellite's coverage area can include multiple TAs, even if a terminal device enters the mobility-restricted area of ​​Network #2, if the TAI broadcast by the satellite also includes other TAs that do not belong to the mobility-restricted area, the terminal device is considered to have not entered the mobility-restricted area of ​​Network #1.

[0261] For example, the satellite's coverage area includes TA1 and TA2. TA2 is within the terminal device's restricted mobility area, while TA1 is not. When the terminal device enters TA2 from TA1, the TA information broadcast by the ground access network equipment changes from TA1 to TA2. Therefore, in Network #2, the terminal device enters the restricted area. If the TA information broadcast by the satellite includes both TA1 and TA2, since TA1 is not within the terminal device's restricted mobility area, it can be considered that the terminal device has not entered the restricted mobility area of ​​Network #1.

[0262] In summary, in a multi-connection scenario, the two networks a terminal device accesses may impose different restrictions on the terminal device's mobility, or in other words, the two networks' management of the terminal device's mobility may not be coordinated. Because the two networks manage the terminal device's mobility independently, the terminal device may still be able to access related services in certain mobility-restricted areas.

[0263] For example, the terminal device is located within the mobility restriction area of ​​the first network, but not within the mobility restriction area of ​​the second network. If the first network and the second network manage the mobility of the terminal device separately, in the first network, since the terminal device is located within the mobility restriction area of ​​the first network, the terminal device cannot obtain the relevant service (for example, service #1), but in the second network, since the terminal device is located outside the mobility restriction area of ​​the second network, the terminal device can obtain service #1. That is, the two networks have inconsistent management of the terminal device's mobility, resulting in the terminal device being located within the mobility restriction area of ​​the first network, but still being able to obtain service #1.

[0264] In addition, if the terminal device is within the mobility restriction area of ​​the second network but not within the mobility restriction area of ​​the first network, according to the existing two networks, the mobility of the terminal device is managed independently. The terminal device cannot obtain related services (for example, service #2) in the second network, but the terminal device can obtain service #2 in the first network. In other words, the mobility management of the terminal device by the first network and the second network is not unified.

[0265] To address the above issues, as shown in FIG2 , the present application proposes a method 200 applicable to a communication system in which a terminal device accesses a first network and a second network, wherein the first network includes a first network element. In an embodiment of the present application, in one embodiment, the first network may be an HPLMN network, and the second network may be a V-PLMN network. In another embodiment, the first network may be a first V-PLMN network, and the second network may be a second V-PLMN network, wherein the first V-PLMN network is a primary V-PLMN network, and the second V-PLMN network is a secondary V-PLMN network.

[0266] In addition, in the embodiment of the present application, the first network element may be a first access and mobility management network element, or a unified data management network element, or a first policy control network element.

[0267] For the convenience of description, in the embodiment of the present application, the access and mobility management network element may be an AMF network element, the unified data management network element may be a UDM network element, the policy control network element may be a PCF network element, the access network device may be a RAN, and the authentication service device may be an AUSF network element. Detailed description of this will be omitted below.

[0268] Specifically, the method 200 includes the following steps:

[0269] S200: Establish an association relationship between the first network and the second network.

[0270] Case 1:

[0271] The first AMF in the first network establishes an association with the second AMF in the second network. For details about this process, please refer to method 300 below and will not be described in detail here.

[0272] Case 2:

[0273] The UDM in the first network establishes an association relationship between the first AMF and the second AMF. For details about this process, please refer to method 400 below and will not be described in detail here.

[0274] Case 3:

[0275] The first PCF in the first network establishes an association relationship with the second PCF in the second network. For this process, please refer to the method 500 below, which will not be described in detail here.

[0276] S201: A first network element determines whether a terminal device enters a mobility restriction area of ​​a first network.

[0277] The following describes several situations in which S201 is triggered:

[0278] Scenario A:

[0279] The first network element is the first AMF.

[0280] Step 1: The terminal device sends a mobility registration update request message to the first AMF.

[0281] It is understandable that, in the first network, if the terminal device leaves the current registration area, the terminal device will send a mobility registration update request message to the device in the first network.

[0282] Step 2: The first AMF determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the mobility registration update request message. The mobility registration update request message includes the identifier of the area (TA) where the terminal device is currently located.

[0283] It can be understood that if the TA in which the terminal device is currently located is in the mobility restriction area list, the first AMF determines that the terminal device enters the mobility restriction area of ​​the first network.

[0284] If the TA in which the terminal device is currently located is not in the mobility restriction area list, the first AMF determines that the terminal device has not entered the mobility restriction area of ​​the first network.

[0285] Case B:

[0286] The first network element is UDM.

[0287] Step 1: The terminal device sends a mobility registration update request message to the first AMF.

[0288] Step 2: The first AMF determines whether the terminal device enters the mobility restriction area of ​​the first network based on the mobility registration update request message.

[0289] Step 3: When the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message to the UDM, which indicates that the terminal device enters the mobility restriction area of ​​the first network.

[0290] Step 4: Based on the notification message, the UDM determines that the terminal device has entered the mobility restriction area of ​​the first network.

[0291] Case C:

[0292] The first network element is the first PCF.

[0293] Step 1: The terminal device sends a mobility registration update request message to the first AMF.

[0294] Step 2: The first AMF determines whether the terminal device enters the mobility restriction area of ​​the first network based on the mobility registration update request message.

[0295] Step 3: When the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message to the first PCF, which indicates that the terminal device enters the mobility restriction area of ​​the first network.

[0296] Step 4: The first PCF determines, based on the notification message, that the terminal device has entered the mobility restriction area of ​​the first network.

[0297] Situation D:

[0298] The first network element is the first AMF, UDM or the first PCF.

[0299] Step 1: The terminal device sends a mobility registration update request message to a device in the second network.

[0300] Similarly, in the second network, if the terminal device leaves the current registration area, the terminal device will send a mobility registration update request message to the device in the second network.

[0301] For example, the terminal device can send a mobility registration update request message to the AMF in the second network (referred to as the second AMF).

[0302] Step 2: The device in the second network determines whether the terminal device enters the mobility restriction area of ​​the second network according to the mobility registration update request message.

[0303] For example, the second AMF may determine whether the terminal device enters the mobility restriction area of ​​the second network.

[0304] Step 3: When the terminal device enters the mobility restriction area of ​​the second network, the device in the second network sends fifth information to the first network element. The fifth information indicates that the terminal device has entered the mobility restriction area of ​​the second network.

[0305] For example, the second AMF may send the fifth information to the first network element.

[0306] Step 4: The first network element determines whether the terminal device enters the mobility restriction area of ​​the first network based on the fifth information.

[0307] As an implementation method, if the first network element is the first AMF, the first network element can determine whether the terminal device enters the mobility restriction area of ​​the first network based on the current location of the terminal device.

[0308] As another implementation method, if the first network element is a UDM or a first PCF, the first network element can send a query message to the first AMF and determine whether the terminal device enters the mobility restriction area of ​​the first network based on the response message of the first AMF to the query message.

[0309] As another implementation method, if the first network element is a UDM or a first PCF, the first network element can determine whether the terminal device enters the mobility restriction area of ​​the first network based on whether a message related to the terminal device mobility update is received from the first AMF.

[0310] For the above cases A to D, the method further includes S202 - 1 and S203 - 1 .

[0311] S202-1: When a terminal device enters a mobility restriction area of ​​a first network, the first network element sends third information to a device in a second network. Correspondingly, the device in the second network receives the third information.

[0312] The third information is used to instruct the second network to stop providing services to the terminal device. Specifically, the third information is used to indicate one or more of the following:

[0313] Instructing the terminal device to enter the mobility restriction area of ​​the first network; instructing the terminal device to be deregistered; instructing the release of all sessions of the terminal device; instructing the cessation of information interaction with the terminal device; instructing the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, which is the area where the terminal device is located.

[0314] S203-1: The device in the second network stops providing services to the terminal device according to the third information.

[0315] Case 1:

[0316] For example, the third information may indicate that the terminal device has entered a forbidden area of ​​the first network or may indicate that the terminal device is to be deregistered. Optionally, the third information may also indicate one or more of releasing all sessions of the terminal device, stopping information interaction with the terminal device, and updating a forbidden area list of the second network for the terminal device.

[0317] As one approach, the device in the second network can deregister the terminal device based on the third information. For example, the device in the second network can send a deregistration request message to the terminal device. Optionally, the deregistration request message can also include a reason for deregistering the terminal device, where the reason is that the terminal device has entered a mobility-restricted area of ​​the first network.

[0318] It is understandable that, during the process of deregistering the terminal device, the device in the second network may release all sessions with the terminal device and stop information interaction with the terminal device.

[0319] Case 2:

[0320] For example, the third information may indicate that the terminal device has entered a non-allowed area of ​​the first network. Optionally, the third information may also indicate one or more of releasing all sessions of the terminal device or updating a non-allowed area list of the second network for the terminal device. Optionally, unlike scenario 1, in scenario 2, the terminal device may still remain registered.

[0321] As a way, the device in the second network can restrict the terminal device from establishing a new session and restrict the terminal device from obtaining related services based on the third information. In addition, the device in the second network can release all sessions with the terminal device.

[0322] As another approach, the device in the second network may stop exchanging information other than mobility-related information with the terminal device based on the third information. That is, at this time, the device in the second network may only exchange mobility-related information with the terminal device.

[0323] In addition, optionally, for the above-mentioned situation 1 and situation 2, the device in the second network can also update the mobility restriction area list of the terminal device in the second network based on the third information, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area (TA), and the first area is the area where the terminal device is currently located.

[0324] For the above situation D, the method further includes S202-2 and S203-2.

[0325] S202-2: When the terminal device does not enter the mobility restriction area of ​​the first network, the first network element sends sixth information to the device in the second network. Correspondingly, the device in the second network receives the sixth information.

[0326] The sixth information is used to indicate any one of the following:

[0327] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located.

[0328] S203-2: The device in the second network provides a service to the terminal device according to the sixth information.

[0329] As a case, the device in the second network may accept the mobility registration update request of the terminal device according to the sixth information.

[0330] Optionally, the device in the second network can update the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area. It can be understood that in this case, the sixth information includes the first area.

[0331] According to the method 200 proposed in the present application, the first network and the second network can collaboratively manage the mobility of the terminal device, so that the mobility restrictions of the terminal device imposed by the first network and the second network are consistent.

[0332] The method 200 is described in detail below for different types of first network elements.

[0333] FIG3 shows a method 300 proposed in this application. In this method 300, the first network element is a first AMF. Specifically, the method 300 includes the following steps.

[0334] Among them, the first network includes a first AMF, an AUSF, an UDM, a first RAN, and a first PCF, and the second network includes a second AMF, a second RAN, and a second PCF.

[0335] S301: The terminal device completes the registration process in the first network and obtains information #100 (ie, first information).

[0336] Information #100 includes an identifier of the first AMF in the first network. In other words, information #100 is used to identify the first AMF in the first network. Exemplarily, information #100 may be a globally unique temporary identity (GUTI) assigned by the first AMF to the terminal device, or may be a globally unique AMF identifier (GUAMI).

[0337] The 5G-GUTI includes the GUAMI and the 5G temporary mobile subscriber identity (TMSI). Furthermore, the GUAMI includes the mobile country code (MCC), mobile network code (MNC), and AMF ID. The 5G-TMSI is the temporary identifier of the terminal device. The MCC and MNC are the identifiers of the PLMN, and the AMF ID is the identifier of the AMF.

[0338] It is understood that the terminal device obtains the information #100 during the process of registering with the first network. As one embodiment, the terminal device receives a registration acceptance message from the first AMF during the process of registering with the first network. The registration acceptance message includes the 5G-GUTI corresponding to the first AMF. Optionally, the registration acceptance message may also include the GUAMI corresponding to the first AMF.

[0339] The process of registering the terminal device to the first network may refer to the existing 3GPP protocol TS23.502.

[0340] S302: The terminal device sends a message #A to the second RAN. Correspondingly, the second RAN receives the message #A.

[0341] This message #A includes AN parameters (parameters associated with AN) and information #100.

[0342] In this embodiment of the present application, the terminal device further obtains information #200 (i.e., second information), which is used to instruct the terminal device to enter a multi-connection state. The terminal device can send information #100 to the second RAN in the second network during the registration process based on information #200.

[0343] As a method, the terminal device can obtain the information #200 based on the user's operation instruction. For example, the user can turn on the multi-connection switch on the terminal device, and further, the terminal device can enter the multi-connection state according to the user's operation instruction.

[0344] Alternatively, the terminal device may obtain the information #200 from the first AMF. In other words, the first AMF may instruct the terminal device to enter a multi-connection state.

[0345] In addition, the message #A may also indicate that the terminal device is in a multi-connection state.

[0346] Optionally, the message #A may implicitly indicate that the terminal device is in a multi-connection state. For example, the message #100 may be used to implicitly indicate that the terminal device is in a multi-connection state.

[0347] Optionally, the message #A may explicitly indicate that the terminal device is in a multi-connection state. For example, the message #A may further include information indicating that the terminal device is in a multi-connection state (or, the message #A may further include information #200). In the embodiment of the present application, the terms "indication information indicating that the terminal device is in a multi-connection state," "information #200," and "second information" may be interchangeable.

[0348] Exemplarily, the message #A is an access network (AN) message.

[0349] Taking the example of message #A explicitly indicating that the terminal device is in a multi-connection state, as one case, information #100 and the indication that the terminal device is in a multi-connection state can be included in the registration request message. That is, the AN message can include AN parameters and the registration request message, and the registration request message includes information #100 and the indication that the terminal device is in a multi-connection state.

[0350] The registration request message is used to request registration with the second network, and details of the registration request message will not be given in detail below.

[0351] As another case, the information #100 and the indication information that the terminal device is in a multi-connection state may be included in the AN parameter. That is, the AN message includes the AN parameter, and the AN parameter includes the information #100 and the indication information that the terminal device is in a multi-connection state.

[0352] In another case, the AN message includes AN parameters, a registration request message, information #100, and information indicating that the terminal device is in a multi-connection state. That is, the AN parameters, the registration request message, information #100, and information indicating that the terminal device is in a multi-connection state exist in parallel.

[0353] S303: The second RAN selects an AMF based on the AN parameters (the AMF selected by the second RAN is recorded as the second AMF).

[0354] As a method, the second RAN can select an AMF with multi-connection capability based on the indication information that the terminal device is in a multi-connection state.

[0355] S304: The second RAN sends message #B to the second AMF. Accordingly, the second AMF receives message #B.

[0356] The message #B includes information #100. In addition, the message #B is also used to indicate that the terminal device is in a multi-connection state.

[0357] Optionally, the message #B may implicitly indicate that the terminal device is in a multi-connection state. For example, the message #100 may be used to implicitly indicate that the terminal device is in a multi-connection state.

[0358] Optionally, message #B may explicitly indicate that the terminal device is in a multi-connection state. For example, message #B may further include information indicating that the terminal device is in a multi-connection state. In S302, if information #100 and the information indicating that the terminal device is in a multi-connection state are included in the registration request message, message #B may be the registration request message.

[0359] Of course, the message #B can also be other types of messages, and this application does not limit this.

[0360] It can be understood that after receiving message #B, the second AMF determines that the terminal device is in a multi-connection state. The second AMF establishes an association relationship with the first AMF. As a way, the second AMF can save the association relationship between the first AMF, the second AMF and the terminal device (denoted as association relationship #1), for example, the association relationship between the identifier of the first AMF, the identifier of the second AMF and the identifier of the terminal device can be saved. As another way, the second AMF can save the association relationship between the first AMF and the terminal device (denoted as association relationship #2), for example, the association relationship between the identifier of the first AMF and the identifier of the terminal device can be saved.

[0361] The terminal device may send the identifier of the terminal device to the second AMF through the second RAN.

[0362] It can be understood that the second AMF saves association relationship #1 or association relationship #2 in order to subsequently collaborate with the first AMF to manage the mobility of the terminal device. This will not be explained in detail for now.

[0363] S305, the second AMF selects AUSF.

[0364] S306: The terminal device, the second AMF, AUSF, and UDM interact to complete the security process.

[0365] For details about this process, please refer to the existing 3GPP protocol TS23.502.

[0366] For example, the terminal device, the second AMF, AUSF, and UDM can interact to complete the authentication security process.

[0367] S307: The second AMF sends message #C to the UDM. Accordingly, the UDM receives message #C.

[0368] The message #C is used to indicate that the terminal device is in a multi-connection state. For example, the message #C includes information indicating that the terminal device is in a multi-connection state. Exemplarily, the message #C is a terminal device context registration request message. The message #C may include an identifier of the terminal device.

[0369] Specifically, the UDM may update the status of the terminal device stored in the UDM according to the message #C. After the update, the status of the terminal device stored in the UDM is a multi-connection state.

[0370] S308: The UDM sends message #D (a response message to message #C) to the second AMF. Accordingly, the second AMF receives message #D.

[0371] Exemplarily, the message #D is a terminal device context registration response message.

[0372] S309: The second AMF sends message #E to the first AMF based on information #100. In response, the first AMF receives message #E.

[0373] It can be understood that in S302, the second AMF obtains information #100 from message #A. Further, the second AMF can determine the first AMF based on information #100 and send message #E to the first AMF.

[0374] The message #E is used to indicate that the terminal device is in a multi-connection state. The message #E may include an identifier of the terminal device.

[0375] Optionally, the message #E may explicitly indicate that the terminal device is in a multi-connection state. For example, the message #E may include indication information that the terminal device is in a multi-connection state.

[0376] In addition, message #E also includes information #300 (i.e., fourth information). Information #300 includes the identifier of the second AMF. In other words, information #300 is used to determine the second AMF. For example, information #300 is the 5G-GUTI corresponding to the second AMF, or the GUAMI corresponding to the second AMF.

[0377] Exemplarily, the message #E is a terminal device context update request message.

[0378] It can be understood that after receiving message #E, the first AMF determines that the terminal device is in a multi-connection state. The first AMF can establish an association relationship with the second AMF. As a way, the first AMF can save the association relationship between the first AMF, the second AMF and the terminal device (denoted as association relationship #A), for example, the association relationship between the identifier of the first AMF, the identifier of the second AMF and the identifier of the terminal device can be saved. As another way, the first AMF can save the association relationship between the second AMF and the terminal device, for example, the association relationship between the identifier of the second AMF and the identifier of the terminal device can be saved (denoted as association relationship #B).

[0379] It can be understood that the first AMF saves the association relationship #A or the association relationship #B in order to subsequently collaborate with the second AMF to manage the mobility of the terminal device. This will not be explained in detail for now.

[0380] S310: The first AMF sends information about the network element serving the terminal device in the first network to the second AMF based on information #300. In response, the second AMF receives the information about the network element serving the terminal device in the first network.

[0381] For example, the first AMF may send information of the first PCF serving the terminal device in the first network to the second AMF.

[0382] S311, the first AMF obtains a first policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends third information to the second AMF.

[0383] The third information is used to instruct the second network to stop providing services to the terminal device. Specifically, the third information is used to indicate one or more of the following:

[0384] Instructing the terminal device to enter the mobility restriction area of ​​the first network; instructing the terminal device to be deregistered; instructing the release of all sessions of the terminal device; instructing the cessation of information interaction with the terminal device; instructing the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, which is the area where the terminal device is located.

[0385] The third information will not be further elaborated below.

[0386] The following describes how the first AMF obtains the first policy.

[0387] Method 1:

[0388] The first AMF obtains first configuration information, which instructs the first AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends third information to the second AMF.

[0389] The first AMF may obtain the first policy according to the first configuration information.

[0390] For example, the first configuration information may be pre-configured into the first AMF.

[0391] Method 2:

[0392] The second AMF sends message #F to the first AMF. In response, the first AMF receives message #F.

[0393] This message #F is used for subscription: If the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends the third information to the second AMF.

[0394] The first AMF may obtain the first policy according to the message #F.

[0395] Method 3:

[0396] The first PCF obtains indication information that the terminal device is in a multi-connection state. As an implementation method, the first AMF may send the indication information that the terminal device is in a multi-connection state to the first PCF during the process of establishing an access and mobility (AM) policy association with the first PCF. In other words, the first AMF may select the first PCF and establish an association with the first PCF, and the first PCF may subsequently send the AM policy to the first AMF.

[0397] The first PCF sends first policy update information to the first AMF based on the indication information that the terminal device is in a multi-connection state.

[0398] The first AMF updates the local policy of the first AMF according to the first policy update information. After the update, the local policy of the first AMF is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the third information is sent to the second AMF.

[0399] S312, the second AMF obtains a second policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends fifth information to the first AMF.

[0400] The fifth information indicates that the terminal device has entered the mobility restriction area of ​​the second network.

[0401] Regarding the fifth information, no further details will be given below.

[0402] The following describes how the second AMF obtains the second policy.

[0403] Method 1:

[0404] The second AMF obtains second configuration information, which instructs the second AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends fifth information to the first AMF.

[0405] The second AMF may obtain the second policy according to the second configuration information.

[0406] For example, the second configuration information may be pre-configured into the second AMF.

[0407] Method 2:

[0408] The first AMF sends message #G to the second AMF. In response, the second AMF receives message #G.

[0409] This message #G is used for subscription: If the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends the fifth information to the first AMF.

[0410] The second AMF may obtain the second policy according to message #G.

[0411] Method 3:

[0412] The second PCF obtains the indication information that the terminal device is in a multi-connection state. As an implementation method, the second AMF may send the indication information that the terminal device is in a multi-connection state to the second PCF during the process of establishing an AM policy association with the second PCF.

[0413] The second PCF sends second policy update information to the second AMF based on the indication information that the terminal device is in a multi-connection state.

[0414] The second AMF updates the local policy of the second AMF according to the second policy update information. After the update, the local policy of the second AMF is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the fifth information is sent to the first AMF.

[0415] S313: The second AMF sends a message #H to the terminal device. Correspondingly, the terminal device receives the message #H.

[0416] This message #H is a registration reception response message.

[0417] That is, the terminal device completes the registration process on the second network.

[0418] After S313, as the terminal device moves, as a first case, the terminal device enters the mobility restriction area of ​​the first network, but the terminal device does not enter the mobility restriction area of ​​the second network. For this case, the method 300 further includes the following steps.

[0419] S314-1: The terminal device sends message #I to the first AMF. In response, the first AMF receives message #I.

[0420] This message #I is used to request a mobility registration update for the terminal device in the first network.

[0421] It can be understood that, in the first network, if the terminal device leaves the current registration area, the terminal device sends the message #I.

[0422] S315-1, the first AMF determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the message #I.

[0423] For example, the first AMF determines whether the terminal device enters a forbidden area of ​​the first network.

[0424] For another example, the first AMF determines whether the terminal device enters a non-allowed area of ​​the first network.

[0425] S316-1, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF stops providing services to the terminal device.

[0426] Case 1:

[0427] The terminal device enters a forbidden area of ​​the first network.

[0428] As a method, the first AMF can send message #J to the terminal device. Accordingly, the terminal device receives message #J. The message #J is used to deregister the terminal device from the first network.

[0429] It is understandable that in the process of deregistering the terminal device, the first AMF may release the session with the terminal device (for example, release all sessions related to the terminal device) and stop information interaction with the terminal device (for example, stop all information interaction with the terminal device).

[0430] Case 2:

[0431] The terminal device enters a non-allowed area of ​​the first network. At this time, optionally, the terminal device can still remain in a registered state.

[0432] As a way, the first AMF can restrict the terminal device from establishing a session and restrict the terminal device from obtaining related services. In addition, the first AMF can release all sessions related to the terminal device.

[0433] Alternatively, the first AMF may stop exchanging information other than mobility-related data with the terminal device. In other words, at this point, the first AMF may only exchange mobility-related information with the terminal device.

[0434] S317-1: When the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a message #K to the second AMF. Correspondingly, the second AMF receives the message #K.

[0435] The message #K includes third information. The third information indicates one or more of the following:

[0436] Instructing the terminal device to enter the mobility restriction area of ​​the first network; instructing the terminal device to be deregistered; instructing the release of all sessions of the terminal device; instructing the cessation of information interaction with the terminal device; instructing the update of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first TA, which is the TA where the terminal device is located in the second network.

[0437] Specifically, the first AMF can find the second AMF according to the first policy obtained in S311 and the association relationship saved in S309, and send message #K to the second AMF.

[0438] It is understandable that the present application does not limit the execution order between S316-1 and S317-1. As a case, S317-1 can also be executed before S316-1.

[0439] S318-1, the second AMF stops providing services to the terminal device according to message #K.

[0440] Case 1:

[0441] The terminal device enters a forbidden area of ​​the first network.

[0442] As a method, the second AMF can send a message #L (e.g., a deregistration request message) to the terminal device based on the third information. Accordingly, the terminal device receives the message #L. The message #L is used to deregister the terminal device. Optionally, the message #L may also include reason information for deregistering the terminal device, where the reason information indicates that the terminal device has entered the mobility restriction area of ​​the first network.

[0443] The second AMF performs a deregistration process for the terminal device. This deregistration process includes releasing the terminal device's session in the second network and releasing the association between the terminal device and the second PCF. Furthermore, the terminal device may send a deregistration acceptance message to the second AMF. In response, the second AMF receives the deregistration acceptance message. Signal connections between the terminal device, the second RAN, and the second AMF may be released. Specifically, the second AMF may instruct the second RAN to release the signal connection between the second RAN and the terminal device. In response, the second RAN may release the signal connection between the terminal device and the second RAN, and the terminal device may also release the signal connection between the terminal device and the second RAN.

[0444] Case 2:

[0445] The terminal device enters a non-allowed area of ​​the first network. At this time, optionally, the terminal device can still remain in a registered state.

[0446] As a way, the second AMF can restrict the terminal device from establishing new sessions and restrict the terminal device from obtaining related services based on the third information. In addition, the second AMF can release all sessions of the terminal device in the second network.

[0447] Alternatively, the second AMF may stop exchanging information other than mobility-related information with the terminal device based on the third information. That is, at this time, the second AMF may only exchange mobility-related information with the terminal device.

[0448] In addition, optionally, for the above-mentioned situation 1 and situation 2, the second AMF can also update the mobility restriction area list of the terminal device in the second network based on the third information, and the updated mobility restriction area list of the terminal device in the second network includes the first area (TA), which is the area where the terminal device is currently located.

[0449] After S313, as the terminal device moves, as a second case, the terminal device does not enter the mobility restriction area of ​​the first network, but enters the mobility restriction area of ​​the second network. For this case, the method 300 further includes the following steps.

[0450] S314-2: The terminal device sends message #M to the second AMF. In response, the second AMF receives message #M.

[0451] This message #M is used to request a mobility registration update for the terminal device in the second network.

[0452] It can be understood that, in the second network, if the terminal device leaves the current registration area, the terminal device sends the message #M.

[0453] S315-2, the second AMF determines whether the terminal device enters the mobility restriction area of ​​the second network.

[0454] For example, the second AMF determines whether the terminal device enters a prohibited area of ​​the second network.

[0455] For another example, the second AMF determines whether the terminal device enters a non-allowed area of ​​the second network.

[0456] S316-2: When the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends message #N to the first AMF. Correspondingly, the first AMF receives message #N.

[0457] The message #N includes fifth information. The fifth information is used to indicate that the terminal device has entered the mobility restriction area of ​​the second network.

[0458] Specifically, the second AMF can find the first AMF according to the second policy obtained in S312 and the association relationship saved in S304, and send message #N to the first AMF.

[0459] S317-2, the first AMF determines whether the terminal device enters the mobility restriction area of ​​the first network based on message #N.

[0460] S318-2: If the terminal device does not enter the mobility restriction area of ​​the first network, the first AMF sends a message #P to the second AMF. Correspondingly, the second AMF receives the message #P.

[0461] The message #P includes sixth information. The sixth information is used to indicate any one of the following:

[0462] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located in the second network.

[0463] Exemplarily, the message #P is a terminal device context update message.

[0464] S319-2, the second AMF provides services to the terminal device according to message #P.

[0465] As a case, the device in the second network may accept the mobility registration update request of the terminal device according to the sixth information, and send a mobility registration update accept message to the terminal device.

[0466] Optionally, the second AMF may also update the mobility restriction area list of the terminal device in the second network according to the sixth information in the message #P, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area.

[0467] According to an embodiment of the present application, the first AMF in the first network and the second AMF in the second network can collaboratively manage the mobility of the terminal device so that the mobility restrictions of the terminal device in the first network and the second network are consistent.

[0468] Figure 4 shows a method 400 proposed in this application, in which the first network element is a UDM. Specifically, the method 400 includes the following steps.

[0469] Among them, the first network includes a first AMF, an AUSF, an UDM, a first RAN, and a first PCF, and the second network includes a second AMF, a second RAN, and a second PCF.

[0470] S401: The terminal device completes the registration process on the first network.

[0471] In the process of the terminal device registering to the first network, the UDM can obtain information #100 (i.e., the first information) from the first AMF in the first network.

[0472] Information #100 includes the identifier of the first AMF. In other words, information #100 is used by the UDM to determine the first AMF in the first network. For more information about information #100, refer to the description in S301.

[0473] S402: The terminal device sends message #1 to the second RAN. Correspondingly, the second RAN receives the message #1.

[0474] This message #1 includes the AN parameter.

[0475] In the embodiment of the present application, the terminal device further obtains information #200 (ie, second information), which is used to instruct the terminal device to enter the multi-connection state. For the manner in which the terminal device obtains information #200, please refer to S302.

[0476] In addition, the message #1 also indicates that the terminal device is in a multi-connection state.

[0477] Optionally, the message #1 may explicitly indicate that the terminal device is in a multi-connection state. For example, the message #1 may also include indication information (ie, information #200) indicating that the terminal device is in a multi-connection state.

[0478] Exemplarily, the message #1 is an AN message.

[0479] Taking message #1 as an example, where it explicitly indicates that the terminal device is in a multi-connection state, as one scenario, the indication that the terminal device is in a multi-connection state can be included in the registration request message. That is, the AN message can include AN parameters and the registration request message, and the registration request message includes the indication that the terminal device is in a multi-connection state.

[0480] For example, the registration request message may additionally carry indication information to indicate that the registration request is for multiple connections.

[0481] For another example, in the registration request message, the registration type information may indicate multi-connection registration.

[0482] As another case, the indication information that the terminal device is in a multi-connection state may be included in an AN parameter. That is, the AN message includes an AN parameter, and the AN parameter includes the indication information that the terminal device is in a multi-connection state.

[0483] As another case, the AN message includes AN parameters, a registration request message, and information indicating that the terminal device is in a multi-connection state. That is, the AN parameters, the registration request message, and information indicating that the terminal device is in a multi-connection state exist in parallel.

[0484] S403: The second RAN selects an AMF based on the AN parameters (the AMF selected by the second RAN is recorded as the second AMF).

[0485] As a method, the second RAN can select an AMF with multi-connection capability based on the indication information that the terminal device is in a multi-connection state.

[0486] S404: The second RAN sends message #2 to the second AMF. Accordingly, the second AMF receives message #2.

[0487] This message #2 is used to indicate that the terminal device is in a multi-connection state.

[0488] As a method, message #2 can explicitly indicate that the terminal device is in a multi-connection state. For example, message #2 includes information indicating that the terminal device is in a multi-connection state. In S402, if the information indicating that the terminal device is in a multi-connection state is included in the registration request message, message #2 can be the registration request message.

[0489] Of course, the message #2 may also be other types of messages.

[0490] S405, the second AMF selects AUSF.

[0491] S406: The terminal device, the second AMF, AUSF, and UDM interact to complete the security process.

[0492] For this, please refer to S306.

[0493] S407: The second AMF sends message #3 to the UDM. Accordingly, the UDM receives message #3.

[0494] The message #3 is used to indicate that the terminal device is in a multi-connection state. For example, the message #3 includes indication information that the terminal device is in a multi-connection state. Exemplarily, the message #3 is a terminal device context registration request message.

[0495] As a method, message #3 may also include information #300 (i.e., fourth information). Information #300 includes the identifier of the second AMF. In other words, information #300 is used by the UDM to determine the second AMF. For example, information #300 is the 5G-GUTI corresponding to the second AMF, or the GUAMI corresponding to the second AMF.

[0496] It can be understood that UDM can save the association relationship between the first AMF, the second AMF and the terminal device based on the indication information that the terminal device is in a multi-connection state, for example, save the association relationship between the identifier of the first AMF, the identifier of the second AMF and the identifier of the terminal device.

[0497] S408: UDM determines that the terminal device is connected to the first network and the second network, and associates the terminal device, the first AMF, and the second AMF.

[0498] The following describes how the UDM determines that the terminal device is connected to the first network and the second network at the same time.

[0499] Method 1:

[0500] The UDM may determine that the terminal device is connected to the first network and the second network at the same time based on the indication information in message #3 that the terminal device is in a multi-connection state.

[0501] Method 2:

[0502] If the UDM detects that the context for the terminal device stored by the UDM includes information about the first AMF and the second AMF, the UDM determines that the terminal device is simultaneously connected to the first network and the second network.

[0503] S409, the first AMF obtains the first policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #1 to the UDM, which indicates that the terminal device enters the mobility restriction area of ​​the first network.

[0504] The following describes how the first AMF obtains the first policy.

[0505] Method 1:

[0506] The first AMF obtains first configuration information, which instructs the first AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #1 to the UDM.

[0507] The first AMF may obtain the first policy according to the first configuration information.

[0508] Method 2:

[0509] The UDM sends message #4-1 to the first AMF. This message #4-1 is used for subscription: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #1 to the UDM.

[0510] The first AMF may obtain the first policy based on the message #4-1.

[0511] Method 3:

[0512] The UDM sends message #4-2 to the first PCF. Message #4-2 is used to instruct the first PCF to update the local policy of the first AMF.

[0513] Furthermore, the first PCF may send a first policy update message to the first AMF based on message #4-2 to update the local policy of the first AMF. After the update, the local policy of the first AMF is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #1 to the UDM.

[0514] S410, the second AMF obtains a second policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends fifth information to the UDM, and the fifth information indicates that the terminal device enters the mobility restriction area of ​​the second network.

[0515] The following describes how the second AMF obtains the second policy.

[0516] Method 1:

[0517] The second AMF obtains second configuration information, which instructs the second AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends fifth information to the UDM.

[0518] The second AMF may obtain the second policy according to the second configuration information.

[0519] Method 2:

[0520] The UDM sends message #5-1 to the second AMF. This message #5-1 is used for subscription: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends the fifth information to the UDM.

[0521] The UDM may obtain the second policy according to message #5-1.

[0522] Method 3:

[0523] The UDM sends message #5-2 to the second PCF. Message #5-2 is used to instruct the second PCF to update the local policy of the second AMF.

[0524] Furthermore, the second PCF can update the local policy of the second AMF based on the message #5-2. The local policy of the second AMF after the update is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends a message to the UDM to instruct the terminal device to enter the mobility restriction area of ​​the second network.

[0525] S411, the second AMF sends a registration reception response message to the terminal device.

[0526] That is, the terminal device completes the registration process on the second network.

[0527] After S411, as the terminal device moves, as a first case, the terminal device enters the mobility restriction area of ​​the first network, but the terminal device does not enter the mobility restriction area of ​​the second network. For this case, the method 400 further includes the following steps.

[0528] S412-1: The terminal device sends message #6 to the first AMF. In response, the first AMF receives message #6.

[0529] This message #6 is used to request a mobility registration update for the terminal device in the first network.

[0530] For this, please refer to S314-1.

[0531] S413-1, the first AMF determines whether the terminal device has entered the mobility restriction area of ​​the first network based on message #6.

[0532] For this, please refer to S315-1.

[0533] S414-1, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF stops providing services to the terminal device.

[0534] For details about this process, please refer to S316-1 and will not be repeated here.

[0535] For example, the first AMF may send message #7 to the terminal device. Accordingly, the terminal device receives message #7. Message #7 is used to deregister the terminal device from the first network.

[0536] S415-1: When the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends message #8 to the UDM. Accordingly, the UDM receives message #8.

[0537] Specifically, the first AMF may send message #8 to the UDM based on the first policy obtained in S409 when the terminal device enters the mobility restriction area of ​​the first network.

[0538] This message #8 (ie, notification message #1 in S409) is used to indicate that the terminal device has entered the mobility restriction area of ​​the first network.

[0539] In addition, the message #8 may include the identifier of the terminal device, and optionally, may also include the identifier of the first AMF.

[0540] It is understandable that the present application does not limit the execution order between S414-1 and S415-1. As a case, S415-1 can also be executed before S414-1.

[0541] S416-1: The UDM sends message #9 to the second AMF based on message #8. Accordingly, the second AMF receives message #9.

[0542] Specifically, since UDM associates the terminal device, the first AMF and the second AMF in S408, after receiving message #8, UDM can determine the second AMF associated with the terminal device and send message #9 to the second AMF.

[0543] Message #9 includes third information indicating at least one of the following:

[0544] Instructing the terminal device to enter the mobility restriction area of ​​the first network; instructing the terminal device to be deregistered; instructing the release of all sessions of the terminal device; instructing the cessation of information interaction with the terminal device; instructing the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, which is the area where the terminal device is currently located in the second network.

[0545] S417-1, the second AMF stops providing services to the terminal device according to message #9.

[0546] For details about this process, please refer to S318-1 and will not be repeated here.

[0547] After S411, as the terminal device moves, as a second case, the terminal device enters the mobility restriction area of ​​the second network, but the terminal device does not enter the mobility restriction area of ​​the first network. For this case, the method 400 further includes the following steps.

[0548] S412-2: The terminal device sends message #10 to the second AMF. In response, the second AMF receives message #10.

[0549] The message #10 is used to request a mobility registration update for the terminal device in the second network.

[0550] For this, please refer to S314-2.

[0551] S413-2, the second AMF determines whether the terminal device enters the mobility restriction area of ​​the second network.

[0552] For this, please refer to S315-2.

[0553] S414-2: When the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends message #11 to the UDM. Accordingly, the UDM receives message #11.

[0554] Specifically, the second AMF may send message #11 to the UDM based on the second policy obtained in S410 when the terminal device enters the mobility restriction area of ​​the second network.

[0555] The message #11 includes fifth information. The fifth information is used to indicate that the terminal device has entered the mobility restriction area of ​​the second network.

[0556] In addition, the message #11 may include the identifier of the terminal device, and optionally, may also include the identifier of the second AMF.

[0557] S415-2: The UDM determines whether the terminal device enters the mobility restriction area of ​​the first network based on the message #11.

[0558] The following describes several ways in which the UDM determines whether the terminal device has entered the mobility restriction area of ​​the first network:

[0559] Method A:

[0560] Method A includes the following steps:

[0561] Step 1: According to message #11, the UDM sends a query message to the first AMF. The query message is used to query whether the terminal device enters the mobility restriction area of ​​the first network.

[0562] Specifically, UDM associates the terminal device, the first AMF and the second AMF in S408. UDM can determine the first AMF associated with the terminal device based on message #11 and send a query message to the first AMF.

[0563] Step 2: The first AMF sends a response message to the UDM based on the query message.

[0564] As a way, the response message may directly indicate whether the terminal device enters the mobility restriction area of ​​the first network.

[0565] As a method, the response message may indirectly indicate whether the terminal device has entered the mobility restriction area of ​​the first network. For example, the response message may include information about the area where the terminal device is located in the first network.

[0566] Step 3: The UDM determines whether the terminal device enters the mobility restriction area of ​​the first network based on the response message.

[0567] It can be understood that if the response message includes the area information of the terminal device in the first network, the UDM can determine whether the terminal device is currently in the mobility restriction area of ​​the first network based on the mobility restriction area information of the terminal device in the first network stored in the contract data of the terminal device.

[0568] Method B:

[0569] Since the first AMF obtains the first policy in S409, if the UDM does not receive notification message #1 from the first AMF, which notification message #1 indicates that the terminal device has entered the mobility restriction area of ​​the first network, the UDM can determine that the terminal device has not entered the mobility restriction area of ​​the first network. If the UDM receives the notification message #1 from the first AMF, the UDM can determine that the terminal device has entered the mobility restriction area of ​​the first network.

[0570] S416-2: If the terminal device does not enter the mobility restriction area of ​​the first network, the UDM sends message #12 to the second AMF. Accordingly, the second AMF receives message #12.

[0571] The message #12 includes sixth information. The sixth information is used to indicate any one of the following:

[0572] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located in the second network.

[0573] Exemplarily, the message #12 is a terminal device context update message.

[0574] S417-2, the second AMF provides services to the terminal device according to message #12.

[0575] For details about this process, please refer to S319-2 and will not be repeated here.

[0576] According to an embodiment of the present application, the UDM in the first network can collaboratively manage the mobility of the terminal device in the first network and the second network, so that the mobility restrictions of the terminal device in the first network and the second network remain consistent.

[0577] Figure 5 shows a method 500 proposed in this application, in which the first network element is a first PCF. Specifically, the method 500 includes the following steps.

[0578] S501: The terminal device completes the registration process on the first network.

[0579] S502: The terminal device sends a message #a to the second RAN. Correspondingly, the second RAN receives the message #a.

[0580] The message #a includes the AN parameter. In addition, the message #a also indicates that the terminal device is in a multi-connection state.

[0581] For details about this process, please refer to S402 and will not be described in detail here.

[0582] S503: The second RAN selects an AMF based on the AN parameters (the AMF selected by the second RAN is recorded as the second AMF).

[0583] As a method, the second RAN can select an AMF with multi-connection capability based on the indication information that the terminal device is in a multi-connection state.

[0584] S504: The second RAN sends message #b to the second AMF. In response, the second AMF receives message #b.

[0585] This message #b is used to indicate that the terminal device is in a multi-connection state.

[0586] For details about this process, please refer to S404 and will not be described in detail here.

[0587] S505, the second AMF selects AUSF.

[0588] S506: The terminal device, the second AMF, AUSF, and UDM interact to complete the security process.

[0589] S507: The second AMF sends message #c to the UDM. Accordingly, the UDM receives message #c.

[0590] The message #c is used to indicate that the terminal device is in a multi-connection state. For example, the message #c includes indication information that the terminal device is in a multi-connection state. Exemplarily, the message #c is a terminal device context registration request message.

[0591] The UDM may update the terminal device's status based on the message #c. After the update, the terminal device's status is a multi-connection state. Furthermore, the UDM may send a response message to the second AMF for the message #c.

[0592] S508: The second AMF sends message #d to the second PCF. In response, the second PCF receives message #d.

[0593] The message #d is used to indicate that the terminal device is in a multi-connection state. For example, the message #d includes indication information that the terminal device is in a multi-connection state. Exemplarily, the message #d can be used to establish an AM policy association.

[0594] In this embodiment of the present application, the second PCF determines, based on message #d, that the terminal device is in a multi-connection state. The second PCF may establish an association with the first PCF to collaboratively manage the mobility of the terminal device with the first PCF. For example, the second PCF may associate the terminal device with the first PCF and the second PCF, or in other words, associate the terminal device with the first PCF.

[0595] As a method, the second PCF can select a suitable first PCF and associate the terminal device, the first PCF and the second PCF. In addition, the second PCF can also send an identifier of the second PCF to the first PCF.

[0596] As another approach, during access to the first network, the terminal device can obtain the identifier of the first PCF from the first AMF. In S502, the message #a sent by the terminal device to the second RAN may also include the identifier of the first PCF. Furthermore, the second RAN may send the identifier of the first PCF to the second PCF via the second AMF. Furthermore, the second PCF may associate the terminal device with the first PCF and the second PCF. Furthermore, the second PCF may also send its identifier to the first PCF.

[0597] S509: The UDM sends a message #e to the first PCF. Correspondingly, the first PCF receives the message #e.

[0598] The message #e is used to indicate that the terminal device is in a multi-connection state. For example, the message #e includes indication information that the terminal device is in a multi-connection state.

[0599] In this embodiment of the present application, the first PCF determines that the terminal device is in a multi-connection state based on message #e. The first PCF may establish an association with the second PCF to collaboratively manage the mobility of the terminal device. For example, the first PCF may associate the terminal device with the first PCF and the second PCF, or in other words, associate the terminal device with the second PCF. The manner in which the first PCF obtains the identifier of the second PCF can be referred to in S508.

[0600] It is understandable that this application does not limit the execution order between S508 and S509.

[0601] S510, the first AMF obtains a first policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #A to the first PCF, and the notification message #A indicates that the terminal device enters the mobility restriction area of ​​the first network.

[0602] The following describes how the first AMF obtains the first policy.

[0603] Method 1:

[0604] The first AMF obtains first configuration information, which instructs the first AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #A to the first PCF.

[0605] The first AMF may obtain the first policy according to the first configuration information.

[0606] Method 2:

[0607] The first PCF sends a message #f-1 to the first AMF. This message #f-1 is used to subscribe: if the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #A to the first PCF.

[0608] The first AMF may obtain the first policy based on the message #f-1.

[0609] Method 3:

[0610] The first PCF sends message #f-2 to the first AMF. Message #f-2 is used to update the local policy of the first AMF.

[0611] Furthermore, the first AMF can update the local policy of the first AMF based on the message #f-2. After the update, the local policy of the first AMF is: if the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a notification message #A to the first PCF.

[0612] S511, the second AMF obtains the second policy, which is: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends a notification message #B to the second PCF, and the notification message #B indicates that the terminal device enters the mobility restriction area of ​​the second network.

[0613] The following describes how the second AMF obtains the second policy.

[0614] Method 1:

[0615] The second AMF obtains second configuration information, which instructs the second AMF: if the terminal device is in a multi-connection state, when the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends a notification message #B to the UDM.

[0616] The second AMF may obtain the second policy according to the second configuration information.

[0617] Method 2:

[0618] The second PCF sends a message #g-1 to the second AMF. This message #g-1 is used to subscribe: if the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends a notification message #B to the second PCF.

[0619] The ER AMF may obtain the second policy according to the message #g-1.

[0620] Method 3:

[0621] The second PCF sends message #g-2 to the second AMF. Message #g-2 is used to update the local policy of the second AMF.

[0622] Furthermore, the second AMF can update the local policy of the second AMF based on the message #g-2. After the update, the local policy of the second AMF is: if the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends a notification message #B to the second PCF.

[0623] S512: The second AMF sends a registration reception response message to the terminal device.

[0624] That is, the terminal device completes the registration process on the second network.

[0625] After S512, as the terminal device moves, as a first case, the terminal device enters the mobility restriction area of ​​the first network, but the terminal device does not enter the mobility restriction area of ​​the second network. For this case, the method 500 further includes the following steps.

[0626] S513-1: The terminal device sends message #h to the first AMF. In response, the first AMF receives message #h.

[0627] This message #h is used to request a mobility registration update for the terminal device in the first network.

[0628] For this, please refer to S314-1.

[0629] S514-1, the first AMF determines whether the terminal device has entered the mobility restriction area of ​​the first network based on the message #h.

[0630] For this, please refer to S315-1.

[0631] S515-1, when the terminal device enters the mobility restriction area of ​​the first network, the first AMF stops providing services to the terminal device.

[0632] For details about this process, please refer to S316-1 and will not be repeated here.

[0633] For example, the first AMF may send message #i to the terminal device. In response, the terminal device receives message #i. Message #i is used to deregister the terminal device from the first network.

[0634] S516-1: When the terminal device enters the mobility restriction area of ​​the first network, the first AMF sends a message #j to the first PCF. Accordingly, the first PCF receives the message #j.

[0635] Specifically, the first AMF can send message #j to the first PCF based on the first policy obtained in S510 when the terminal device enters the mobility restriction area of ​​the first network.

[0636] This message #j (ie, the notification message #A in S510 ) is used to indicate that the terminal device has entered the mobility restriction area of ​​the first network.

[0637] In addition, the message #j may include the identifier of the terminal device.

[0638] It is understandable that the present application does not limit the execution order between S515-1 and S516-1. As a case, S516-1 can also be executed before S515-1.

[0639] S517-1: The first PCF sends third information to the second AMF via the second PCF based on message #j. Correspondingly, the second AMF receives the third information from the first PCF via the second PCF.

[0640] The third information indicates one or more of the following:

[0641] Instructing the terminal device to enter the mobility restriction area of ​​the first network; instructing the terminal device to be deregistered; instructing the release of all sessions of the terminal device; instructing the cessation of information interaction with the terminal device; instructing the updating of the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network includes the first area, which is the area where the terminal device is currently located in the second network.

[0642] Specifically, the first PCF may determine the second PCF associated with the terminal device based on message #j and send the third information to the second PCF. Further, the second PCF may send the third information to the second AMF.

[0643] S518-1, the second AMF stops providing services to the terminal device based on the third information.

[0644] For details about this process, please refer to S318-1 and will not be repeated here.

[0645] For example, the second AMF may send a message #k to the terminal device. In response, the terminal device receives the message #k. The message #k is used to deregister the terminal device.

[0646] After S512, as the terminal device moves, as a second case, the terminal device does not enter the mobility restriction area of ​​the first network, but enters the mobility restriction area of ​​the second network. For this case, the method 500 further includes the following steps.

[0647] S513-2: The terminal device sends message #m to the second AMF. In response, the second AMF receives message #m.

[0648] This message #m is used to request a mobility registration update for the terminal device in the second network.

[0649] For this, please refer to S314-2.

[0650] S514-2, the second AMF determines whether the terminal device enters the mobility restriction area of ​​the second network.

[0651] For this, please refer to S315-2.

[0652] S515-2: When the terminal device enters the mobility restriction area of ​​the second network, the second AMF sends message #n to the second PCF. Accordingly, the second PCF receives message #n.

[0653] This message #n (ie, the notification message #B in S511) is used to indicate that the terminal device has entered the mobility restriction area of ​​the second network.

[0654] Specifically, the second AMF may send a message #n to the second PCF according to the second policy obtained in S511. The message #n also includes an identifier of the terminal device.

[0655] S516-2: The second PCF sends a message #p to the first PCF. Correspondingly, the first PCF receives the message #p.

[0656] Specifically, the second PCF may determine the first PCF associated with the terminal device based on the message #n, and send a message #p to the first PCF, where the message #p includes fifth information indicating that the terminal device has entered the mobility restriction area of ​​the second network.

[0657] S517-2: The first PCF determines whether the terminal device enters the mobility restriction area of ​​the first network based on the message #p.

[0658] The following describes several ways in which the first PCF determines whether the terminal device enters the mobility restriction area of ​​the first network:

[0659] Method A:

[0660] Method A includes the following steps:

[0661] Step 1: The first PCF sends a query message to the first AMF based on the fifth information. The query message is used to query whether the terminal device enters the mobility restriction area of ​​the first network.

[0662] Step 2: The first AMF sends a response message to the first PCF based on the query message.

[0663] As a way, the response message may directly indicate whether the terminal device enters the mobility restriction area of ​​the first network.

[0664] As a method, the response message may indirectly indicate whether the terminal device has entered the mobility restriction area of ​​the first network. For example, the response message may include information about the area where the terminal device is located in the first network.

[0665] Step 3: The first PCF determines whether the terminal device enters the mobility restriction area of ​​the first network based on the response message.

[0666] It can be understood that if the response message includes the area information of the terminal device in the first network, the first PCF can determine whether the terminal device is currently in the mobility restriction area of ​​the first network based on the mobility restriction area information of the terminal device in the first network stored in the subscription data of the terminal device.

[0667] Method B:

[0668] Since the first AMF obtains the first policy in S510, if the first PCF does not receive the notification message #A from the first AMF, which notification message #A indicates that the terminal device has entered the mobility restriction area of ​​the first network, the first PCF can determine that the terminal device has not entered the mobility restriction area of ​​the first network. If the first PCF receives the notification message #A from the first AMF, the first PCF can determine that the terminal device has entered the mobility restriction area of ​​the first network.

[0669] S518-2: If the terminal device does not enter the mobility restriction area of ​​the first network, the first PCF sends the sixth information to the second AMF through the second PCF. Correspondingly, the second AMF receives the sixth information through the second PCF.

[0670] The sixth information is used to indicate any one of the following:

[0671] Indicates that the terminal device has not entered the mobility restriction area of ​​the first network; indicates acceptance of the mobility registration update of the terminal device; indicates updating the mobility restriction area list of the terminal device in the second network, and after the update, the mobility restriction area list of the terminal device in the second network does not include the first area, and the first area is the area where the terminal device is located in the second network.

[0672] Specifically, the first PCF may find the second PCF based on the stored association relationship between the first PCF, the second PCF, and the terminal device, and send the sixth information to the second PCF. Further, the second PCF may send the sixth information to the second AMF.

[0673] S519-2, the second AMF provides services to the terminal device based on the sixth information.

[0674] For details about this process, please refer to S319-2 and will not be repeated here.

[0675] According to an embodiment of the present application, the first PCF in the first network and the second PCF in the second network can collaboratively manage the mobility of the terminal device in the first network and the second network, so that the mobility restrictions of the terminal device in the first network and the second network are consistent.

[0676] The above describes the method proposed in this application. FIG6 shows a communication device provided in an embodiment of this application, which includes a transceiver unit and a processing unit.

[0677] The transceiver unit can be used to implement corresponding information transmission and reception functions. The transceiver unit can also be called a communication interface or a communication unit. The processing unit can be used to perform processing operations.

[0678] Exemplarily, the device further includes a storage unit, which can be used to store instructions and / or data, and the processing unit can read the instructions and / or data in the storage unit so that the device implements the actions of the device in the aforementioned various method embodiments.

[0679] As an implementation method, the device can be the first AMF in the aforementioned embodiment, or a component (such as a chip) of the first AMF. The transceiver unit and the processing unit can be used to implement the relevant operations of the first AMF.

[0680] For example, the transceiver unit may be used to implement S310, S316-1, and S317-1, and the processing unit may be used to implement S315-1.

[0681] For another example, the transceiver unit may be used to implement S318 - 2 , and the processing unit may be used to implement S317 - 2 .

[0682] For another example, the transceiver unit may be used to implement S414 - 1 and S415 - 1 , and the processing unit may be used to implement S413 - 1 .

[0683] For another example, the transceiver unit may be used to implement S515 - 1 and S516 - 1 , and the processing unit may be used to implement S514 - 1 .

[0684] As another implementation, the device may be the second AMF in the aforementioned embodiment, or a component (such as a chip) of the second AMF. The transceiver unit and the processing unit may be used to implement the relevant operations of the second AMF.

[0685] For example, the transceiver unit may be used to implement S307, S309, S313, and S318-1.

[0686] For another example, the transceiver unit may be used to implement S316-2 and S319-2, and the processing unit may be used to implement S315-2.

[0687] For another example, the transceiver unit can be used to implement S417 - 1 .

[0688] For another example, the transceiver unit may be used to implement S414 - 2 and S417 - 2 , and the processing unit may be used to implement S413 - 2 .

[0689] For another example, the transceiver unit can be used to implement S518 - 1 .

[0690] For another example, the transceiver unit may be used to implement S515 - 2 and S519 - 2 , and the processing unit may be used to implement S514 - 2 .

[0691] As another implementation, the device may be the UDM in the aforementioned embodiment, or a component of the UDM (such as a chip), wherein the transceiver unit and the processing unit may be used to implement related operations of the UDM.

[0692] For example, the transceiver unit may be used to implement S416 - 1 , and the processing unit may be used to implement S408 .

[0693] For another example, the transceiver unit may be used to implement S461 - 2 , and the processing unit may be used to implement S408 and S415 - 2 .

[0694] As another implementation, the device may be the first PCF in the aforementioned embodiment, or a component (such as a chip) of the first PCF. The transceiver unit and the processing unit may be used to implement related operations of the first PCF.

[0695] For example, a transceiver unit may be used to implement S517 - 1 .

[0696] For another example, the transceiver unit may be used to implement S518 - 2 , and the processing unit may be used to implement S517 - 2 .

[0697] As another implementation, the device may be the second PCF in the aforementioned embodiment, or a component (such as a chip) of the second PCF. The transceiver unit and the processing unit may be used to implement related operations of the second PCF.

[0698] For example, a transceiver unit may be used to implement S517 - 1 .

[0699] For another example, the transceiver unit can be used to implement S516 - 2 and S518 - 2.

[0700] As another implementation, the device may be the second RAN in the aforementioned embodiment, or a component (such as a chip) of the second RAN. The transceiver unit and the processing unit may be used to implement related operations of the second RAN.

[0701] For example, the transceiver unit may be used to implement S304, and the processing unit may be used to implement S303.

[0702] For another example, the transceiver unit may be used to implement S404, and the processing unit may be used to implement S403.

[0703] For another example, the transceiver unit may be used to implement S504, and the processing unit may be used to implement S503.

[0704] As another implementation, the device may be the terminal device in the aforementioned embodiment, or a component (such as a chip) of the terminal device. The transceiver unit and the processing unit may be used to implement relevant operations of the terminal device.

[0705] For example, the transceiver unit may be used to implement S302 and S314 - 1 .

[0706] For another example, the transceiver unit can be used to implement S302 and S314 - 2 .

[0707] For another example, the transceiver unit may be used to implement S402 and S412 - 1 .

[0708] For another example, the transceiver unit may be used to implement S402 and S412 - 2 .

[0709] For another example, the transceiver unit can be used to implement S502 and S513 - 1 .

[0710] For another example, the transceiver unit can be used to implement S502 and S513-2.

[0711] It can be understood that the specific process of each unit executing the above corresponding steps has been described in detail in the above method embodiments, and for the sake of brevity, it will not be repeated here.

[0712] The transceiver unit can be replaced by a transceiver (for example, the sending unit in the transceiver unit can be replaced by a transmitter, and the receiving unit in the transceiver unit can be replaced by a receiver), and other units, such as the processing unit, can be replaced by a processor to respectively perform the transceiver operations and related processing operations in each method embodiment.

[0713] In addition, the above-mentioned transceiver unit may also be a transceiver circuit (for example, may include a receiving circuit and a sending circuit), and the processing unit may be a processing circuit.

[0714] Figure 7 illustrates another communication device provided in an embodiment of the present application. The communication device includes a processor and a communication interface. The processor is configured to execute programs or instructions stored in a memory, or read data stored in a memory, to perform the relevant actions in the above method embodiments. For example, there may be one or more processors. The communication interface is configured to receive and / or transmit signals.

[0715] Exemplarily, the communication device may further include a memory for storing computer programs or instructions and / or data. The memory may be integrated with the processor or may be separately provided. Of course, the communication device may also not include the memory, and the memory may be provided externally to the communication device. Exemplarily, there may be one or more memories.

[0716] For example, the processor, communication interface, and memory are interconnected via a bus; the bus may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. These buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the figure uses only one thick line, but this does not imply that there is only one bus or only one type of bus.

[0717] It is understood that the processor mentioned in the embodiments of the present application can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP. The processor can further include a hardware chip. The above-mentioned hardware chip can be an application specific integrated circuit (ASIC), a programmable logic device (PLD). The above-mentioned PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0718] It is also understood that the memory mentioned in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache.

[0719] It is understood that if the embodiments of the present application are implemented in the form of software and sold or used as an independent product, the corresponding program (also referred to as code or instructions) can be stored in a readable storage medium. Therefore, the present application also provides a readable storage medium including a program that, when executed on a device or computer, causes the device or computer to perform any possible implementation of the above-mentioned solution.

[0720] The readable storage media include: U disk, mobile hard disk, ROM, RAM, disk or CD and other media that can store program code.

[0721] The technical solution of the present application can be embodied in the form of a software product. Therefore, the present application also provides a program product, which includes: a program, which, when executed, enables a device or computer to execute any possible implementation of the above solution.

[0722] In addition, an embodiment of the present application further provides a chip system (or chip). The chip system includes a processor and an interface circuit, wherein the interface circuit is used to provide the processor with data, instructions, or information transmission and / or reception, and the processor is used to execute any possible implementation of the above solution.

[0723] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: The method comprises: The communication device obtains first information during registration with the first network, where the first information includes an identifier of a first access and mobility management network element in the first network; The communication device acquires second information, where the second information is used to instruct the communication device to enter a multi-connection state; The communication device sends the first information to the second network in a process of registering to the second network based on the second information, and the first information is used by a second access and mobility management network element in the second network to determine the first access and mobility management network element.

2. The method according to claim 1, characterized in that The first information is a globally unique temporary identifier corresponding to the first access and mobility management network element, or a globally unique access and mobility management network element identifier corresponding to the first access and mobility management network element.

3. The method according to claim 2, characterized in that The communication device obtains first information during registration with the first network, including: The communication device sends a registration request message to the first network; The communication device receives a registration acceptance message from the first access and mobility management network element in the first network, where the registration acceptance message includes a globally unique temporary identifier corresponding to the first access and mobility management network element.

4. The method according to claim 3, characterized in that The registration acceptance message also includes a globally unique access and mobility management network element identifier corresponding to the first access and mobility management network element.

5. The method according to any one of claims 1 to 4, characterized in that The communication device acquires second information, including: The communication device acquires the second information based on an operation instruction of a user; or The communication device obtains the second information from the first access and mobility management network element.

6. The method according to any one of claims 1 to 5, characterized in that The method further comprises: The communication device sends the second information to the second network.

7. A communication method, characterized in that: The method is applied in a scenario where a communication device accesses a first network and a second network, the first network includes a first network element, and the method includes: determining, by the first network element, whether the communication device enters a mobility restriction area of ​​the first network; When the communication device enters the mobility restriction area of ​​the first network, the first network element sends third information to the second network, where the third information is used to instruct the second network to stop providing services to the communication device; and the state of the communication device in the first network is a state of stopping obtaining services.

8. The method according to claim 7, characterized in that The first network element is a first access and mobility management network element, and the method further includes: The first network element receives second information and fourth information from a second access and mobility management network element in the second network, wherein the second information is used to indicate that the communication device is in a multi-connection state, and the fourth information includes an identifier of the second access and mobility management network element.

9. The method according to claim 8, characterized in that The fourth information is a globally unique temporary identifier corresponding to the second access and mobility management network element, or a globally unique access and mobility management network element identifier corresponding to the second access and mobility management network element.

10. The method according to claim 7, characterized in that The first network element is a unified data management network element, and the method further includes: During registration of the communication device with the first network, the first network element obtains first information from a first access and mobility management network element in the first network, where the first information includes an identifier of the first access and mobility management network element; During the process of the communication device registering to the second network, the first network element obtains second information and fourth information from the second access and mobility management network element in the second network, the second information is used to indicate that the communication device is in a multi-connection state, and the fourth information includes an identifier of the second access and mobility management network element.

11. The method according to claim 10, characterized in that The first information is a globally unique temporary identifier corresponding to the first access and mobility management network element, or a globally unique access and mobility management network element identifier corresponding to the first access and mobility management network element; The fourth information is a globally unique temporary identifier corresponding to the second access and mobility management network element, or the second access and Globally unique access and mobility management network element identifier corresponding to the mobility management network element.

12. The method according to any one of claims 7 to 11, characterized in that The third information is used to indicate one or more of the following: Instructing the communication device to enter the mobility restriction area of ​​the first network; instructing to deregister the communication device; instructing to release all sessions of the communication device; instructing to stop information interaction with the communication device; instructing to update the mobility restriction area list of the communication device in the second network, and after the update, the mobility restriction area list of the communication device in the second network includes the first area, and the first area is the area where the communication device is located.

13. The method according to claim 7, characterized in that The first network element is a first access and mobility management network element; The first network element determining whether the communication device enters a mobility restriction area of ​​the first network includes: The first network element receives a mobility registration update request message from the communication device; The first network element determines, based on the mobility registration update request message, whether the communication device enters a mobility restriction area of ​​the first network; The first network element sending the third information to the second network includes: The first network element sends the third information to a second access and mobility management network element in the second network.

14. The method according to claim 13, characterized in that The method further comprises: The first network element obtains first configuration information, where the first configuration information is used to instruct the first network element to send the third information to the second access and mobility management network element if the communication device enters a mobility restriction area of ​​the first network; or The first network element receives a first subscription message from the second access and mobility management network element, where the first subscription message is used to subscribe to: if the communication device enters a mobility restriction area of ​​the first network, the first network element sends the third information to the second access and mobility management network element; or The first network element receives first policy update information from a first policy control network element, and updates the local policy of the first network element according to the first policy update information. After the update, the local policy of the first network element is: if the communication device enters the mobility restriction area of ​​the first network, send the third information to the second access and mobility management network element; wherein, the first network includes the first policy control network element.

15. The method according to claim 7, characterized in that The first network element is a unified data management network element; The first network element determining whether the communication device enters a mobility restriction area of ​​the first network includes: The first network element receives a notification message from a first access and mobility management network element, the notification message indicating that the communication device has entered a mobility restriction area of ​​the first network; The first network element determines, based on the notification message, that the communication device has entered a mobility restriction area of ​​the first network; The first network element sending third information to the second network includes: The first network element sends the third information to a second access and mobility management network element in the second network.

16. The method according to claim 15, characterized in that The method further comprises: The first network element sends a first subscription message to the first access and mobility management network element, where the first subscription message is used to subscribe to: if the communication device enters a mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element; or The first network element sends a first indication message to the first policy control network element, and the first indication message is used to instruct the first policy control network element to update the local policy of the first access and mobility management network element. After the update, the local policy of the first access and mobility management network element is: if the communication device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends the notification message to the first network element, and the first network includes the first policy control network element.

17. The method according to claim 7, characterized in that The first network element determining whether the communication device enters a mobility restriction area of ​​the first network includes: The first network element receives fifth information from the second network, the fifth information indicating that the communication device enters a mobility restriction area of ​​the second network; The first network element determines, based on the fifth information, whether the communication device enters a mobility restriction area of ​​the first network.

18. The method according to claim 17, characterized in that The method further includes: when the communication device does not enter the mobility restriction area of ​​the first network, the first network element sends sixth information to the second network, where the sixth information is used to indicate any one of the following: Indicates that the communication device has not entered the mobility restriction area of ​​the first network; Indicates acceptance of the mobility registration update of the communication device New request; instructing to update the mobility restriction area list of the communication device in the second network, and after the update, the mobility restriction area list of the communication device in the second network does not include the first area, where the first area is the area where the communication device is located.

19. The method according to claim 18, characterized in that The first network element is a first access and mobility management network element; The method further comprises: The first network element sends a second subscription message to a second access and mobility management network element in the second network, and the second subscription message is used to subscribe: if the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element.

20. The method according to claim 18, wherein The first network element is a unified data management network element; The first network element receives fifth information from the second network, including: The first network element receives the fifth information from the second access and mobility management network element of the second network; The first network element determining, based on the fifth information, whether the communication device enters a mobility restriction area of ​​the first network includes: The first network element sends a query message to the first access and mobility management network element based on the fifth information, where the query message is used to query whether the communication device has entered the mobility restriction area of ​​the first network; the first network element receives a response message to the query message from the first access and mobility management network element; the first network element determines whether the communication device has entered the mobility restriction area of ​​the first network based on the response message; or The first network element determines, based on whether a notification message is received from the first access and mobility management network element, whether the communication device has entered a mobility restriction area of ​​the first network, the notification message indicating that the communication device has entered the mobility restriction area of ​​the first network; The first network element sending sixth information to the second network includes: The first network element sends sixth information to the second access and mobility management network element.

21. The method according to claim 20, characterized in that The method further comprises: The first network element sends a second subscription message to the second access and mobility management network element, where the second subscription message is used to subscribe to: if the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element; or The first network element sends a second indication message to the second policy control network element, and the second indication message is used to instruct the second policy control network element to update the local policy of the second access and mobility management network element. After the update, the local policy of the second access and mobility management network element is: if the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element.

22. A communication method, characterized in that: The method is applied in a scenario where a communication device accesses a first network and a second network, the first network includes a first network element, and the second network includes a second access and mobility management network element. The method includes: In a case where the communication device enters a mobility restricted area of ​​the first network, the second access and mobility management network element receives third information from the first network element, where the third information is used to instruct the second network to stop providing services to the communication device; The second access and mobility management network element stops providing services to the communication device according to the third information.

23. The method according to claim 22, characterized in that The first network element is a first access and mobility management network element, and the method further includes: The second access and mobility management network element receives first information and second information from the communication device, where the first information includes an identifier of the first access and mobility management network element, and the second information is used to indicate that the communication device is in a multi-connection state; The second access and mobility management network element sends the second information and fourth information to the first access and mobility management network element according to the first information, where the fourth information includes an identifier of the second access and mobility management network element.

24. The method according to claim 23, wherein The first information is a globally unique temporary identifier corresponding to the first access and mobility management network element, or a globally unique access and mobility management network element identifier corresponding to the first access and mobility management network element; The fourth information is a globally unique temporary identifier corresponding to the second access and mobility management network element, or a globally unique access and mobility management network element identifier corresponding to the second access and mobility management network element.

25. The method according to any one of claims 22 to 24, characterized in that The second access and mobility management network element stops providing services to the communication device according to the third information, including: The second access and mobility management network element sends a deregistration request message to the communication device according to the third information, where the deregistration request message is used to deregister the communication device.

26. The method according to claim 25, characterized in that The deregistration request message further includes a reason for deregistering the communication device, where the reason is that the communication device enters a mobility restriction area of ​​the first network.

27. The method according to any one of claims 22 to 24, characterized in that The second access and mobility management network element stops providing services to the communication device according to the third information, including: The second access and mobility management network element releases all sessions of the communication device according to the third information.

28. The method according to any one of claims 22 to 27, characterized in that The method further comprises: The second access and mobility management network element updates the mobility restriction area list of the communication device in the second network based on the third information, and after the update, the mobility restriction area list of the communication device in the second network includes the first area, which is the area where the communication device is located.

29. The method according to any one of claims 22 to 28, wherein: The method further comprises: The second access and mobility management network element receives a mobility registration update request message from the communication device; The second access and mobility management network element determines, based on the mobility registration update request message, whether the communication device enters a mobility restriction area of ​​the second network; In a case where the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends fifth information to the first network element, wherein the fifth information indicates that the communication device has entered the mobility restriction area of ​​the second network; The second access and mobility management network element receives sixth information from the first network element, where the sixth information indicates any one of the following: Indicating that the communication device has not entered the mobility restriction area of ​​the first network; instructing to accept the mobility registration update of the communication device; instructing to update the mobility restriction area list of the communication device in the second network, and after the update, the mobility restriction area list of the communication device in the second network does not include the first area, the first area being the area where the communication device is located; The second access and mobility management network element provides services to the communication device according to the sixth information.

30. The method according to claim 29, wherein The method further comprises: The second access and mobility management network element updates the mobility restriction area list of the communication device in the second network according to the sixth information, and after the update, the mobility restriction area list of the communication device in the second network does not include the first area.

31. The method according to claim 29 or 30, characterized in that The first network element is a first access and mobility management network element or a unified data management network element, and the method further includes: The second access and mobility management network element obtains second configuration information, where the second configuration information is used to instruct the second access and mobility management network element to: if the communication device enters the mobility restriction area of ​​the second network, send the fifth information to the first network element; or The second access and mobility management network element receives a second subscription message from the first network element, where the second subscription message is used to subscribe to: if the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element; or The second access and mobility management network element receives the second policy update information from the second policy control network element, and updates the local policy of the second access and mobility management network element according to the second policy update indication information. After the update, the local policy of the second access and mobility management network element is: if the communication device enters the mobility restriction area of ​​the second network, the second access and mobility management network element sends the fifth information to the first network element, and the second network includes the second policy control network element.

32. A communication method, characterized in that: The method is applied in a scenario where a communication device accesses a first network and a second network, the first network includes a first access and mobility management network element, and the second network includes a second access and mobility management network element. The method includes: The first access and mobility management network element determines whether the communication device enters a mobility restriction area of ​​the first network; When the communication device enters the mobility restriction area of ​​the first network, the first access and mobility management network element sends third information to the second access and mobility management network element, wherein the third information is used to instruct the second network to stop providing services to the communication device; and the first access and mobility management network element stops providing services to the communication device; The second access and mobility management network element stops providing services to the communication device according to the third information.

33. A communication device, characterized in that: The method comprises a unit for executing any one of claims 1 to 6, or a unit for executing any one of claims 7 to 21, or a unit for executing any one of claims 22 to 31.

34. A communication device, characterized in that: include: A communication interface and a processor, wherein the processor is configured to execute a computer program or instruction so that the communication device performs the method according to any one of claims 1 to 6, or the communication device performs the method according to any one of claims 7 to 21, or the communication device performs the method according to any one of claims 22 to 31.

35. A computer-readable storage medium, characterized in that The method comprises a computer program or an instruction, which, when executed on a computer, causes the computer to execute the method according to any one of claims 1 to 6, or causes the computer to execute the method according to any one of claims 7 to 21, or causes the computer to execute the method according to any one of claims 22 to 31.

36. A computer program product, characterized in that The method comprises instructions which, when executed on a computer, cause the computer to execute the method according to any one of claims 1 to 6, or cause the computer to execute the method according to any one of claims 7 to 21, or cause the computer to execute the method according to any one of claims 22 to 31.

37. A chip system, characterized in that: include: Processing circuit, so that the communication device installed with the chip system performs the method as described in any one of claims 1 to 6, or so that the communication device installed with the chip system performs the method as described in any one of claims 7 to 21, or so that the communication device installed with the chip system performs the method as described in any one of claims 22 to 31.

Images