Communication method, apparatus and system

Abstract

The present application provides a communication method, apparatus and system. The method comprises: a second network element receiving a first request message from a first network element in a first network; sending a second request message to a third network element in a second network on the basis of the first request message; receiving a first response message from the third network element; and sending a second response message to the first network element on the basis of the first response message. The first request message is used for requesting connection establishment between a terminal device and the second network, the second network is used for providing a service for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service by means of the first network. According to the method, the second network can autonomously control and manage the connection establishment between the terminal device and the second network, thereby reducing the deployment and maintenance complexity of the second network.

Description

Communication method, device and system

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on September 26, 2023, with application number 202311252870.3 and application name “Communication Methods, Devices and Systems”, the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of communications, and more particularly, to a communication method, device, and system. Background Art

[0004] As the 3rd Generation Partnership Project (3GPP) network evolves from business-oriented (2B) to consumer-oriented (2C), technologies such as slicing, multi-access edge computing (MEC), and local area data network (LADN) have emerged. These technologies support the deployment of subnets within designated locations (such as enterprises, campuses, shopping malls, parks, etc.) and provide customized subnet services to users in that area.

[0005] However, when slicing, MEC, and LADN technologies are used to deploy subnets, the authority of terminal devices to establish connections with the subnets is controlled by the public land mobile network (PLMN), which makes the deployment and maintenance of the subnets very complicated.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide a communication method, apparatus, and system to enable subnet autonomous management of the connection establishment between terminal devices and subnets, thereby reducing the complexity of subnet deployment and maintenance.

[0008] In a first aspect, a communication method is provided. The method may be executed by a second network element, or may be executed by a chip or circuit of the second network element, which is not limited in this application. For ease of description, the following description is based on an example of execution by the second network element.

[0009] The method includes: receiving a first request message from a first network element in a first network, sending a second request message to a third network element in a second network according to the first request message, receiving a first response message from the third network element, and sending a second response message to the first network element according to the first response message.

[0010] Exemplarily, the first network is a large network operator network, such as a PLMN, also referred to as a large network or public network; the second network is a subnet, also referred to as a private network or dedicated network. The first network element is a control plane network element in the large network operator network, such as a session management network element or a mobility management network element. The second network element can be used to serve or manage the second network, or to forward messages between the first network and the second network. For example, the second network element is a sub-network agent (SNA) network element, which is used to serve or manage one or more subnets. The third network element is a control plane network element in the subnet, such as a subnet session management network element.

[0011] The first request message may be used to request establishment of a connection between the terminal device and the second network, or may be used to request access of the terminal device to the second network.

[0012] The second network is used to provide services for the terminal device. The services provided by the second network to the terminal device can be called subnet services.

[0013] The connection between the terminal device and the second network can be called a subnet connection of the terminal device, which is used for the terminal device and the second network to transmit data of the service through the first network.

[0014] The second request message may be used to request establishment of a connection between the terminal device and the second network, or may be used to request access of the terminal device to the second network.

[0015] The first response message is used to indicate whether to accept the establishment of the connection between the terminal device and the second network; the second response message is used to indicate whether to accept the establishment of the connection between the terminal device and the second network.

[0016] Exemplarily, the sending of the second response message to the first network element based on the first response message may be that, when the first response message is used to indicate acceptance of the connection establishment, the second network element sends the second response message to the first network element, and the second response message is used to indicate acceptance of the connection establishment. In this implementation, the first response message and the second response message may also be used to indicate successful establishment of a subnet connection of the terminal device, to indicate acceptance of an access request from the terminal device, to indicate successful access of the terminal device, or to indicate acceptance of establishment of a subnet connection of the terminal device.

[0017] Exemplarily, the sending of the second response message to the first network element based on the first response message may also be that, when the first response message is used to indicate that the connection establishment is not accepted, the second network element sends the second response message to the first network element, and the second response message is used to indicate that the connection establishment is not accepted. In this implementation, the first response message and the second response message may also be used to reject the establishment of a connection between the terminal device and the second network, to indicate a failure to establish a connection between the terminal device and the second network, to indicate a rejection of the terminal device's access request, to indicate a failure to access the terminal device, or to indicate a rejection of the terminal device's subnet connection establishment.

[0018] According to the solution provided in the present application, the second network element sends a message to the third network element in the second network for requesting the establishment of a connection between the terminal device and the second network, so that the third network element determines whether to accept the connection establishment, thereby realizing the second network (i.e., subnet)'s autonomous control over the connection establishment and reducing the complexity of subnet deployment and maintenance.

[0019] With reference to the first aspect, in certain implementations of the first aspect, the first request message includes identification information of the terminal device, and sending the second request message to the third network element based on the first request message may be sending the second request message to the third network element when the user information of the second network includes the identification information of the terminal device. The user information of the second network includes identification information of one or more terminal devices permitted to establish a connection with the second network. In other words, the user information of the second network includes identification information of one or more terminal devices that have signed a contract with the second network.

[0020] Exemplarily, the second network element obtains user information of the second network and determines whether the user information of the second network includes identification information of the terminal device. For example, the second network element obtains user information of the second network from a fourth network element. The fourth network element may be a subnet tenant subscription function network element.

[0021] The second network element sends a second request message to the third network element when the user information of the second network includes the identification information of the terminal device. This can prevent terminal devices that are not allowed to establish a connection with the second network or terminal devices that have not signed a contract with the second network from initiating a connection establishment request to the third network element, thereby avoiding unnecessary signaling overhead, improving transmission resource utilization, reducing the processing complexity of the third network element, and realizing the management and control of the subnet connection establishment by the second network element.

[0022] In conjunction with the first aspect, in certain implementations of the first aspect, when the user information of the second network includes identification information of the terminal device, the method further includes: obtaining subscription data of the second network. For example, the second network element receives the subscription data of the second network from a fourth network element. This avoids the second network element from unnecessarily obtaining the subscription data of the second network, thereby improving resource utilization and reducing signaling overhead.

[0023] In conjunction with the first aspect, in certain implementations of the first aspect, sending the second request message to the third network element in the second network according to the first request message may be, when the first request message and the subscription data of the second network meet a first condition, sending the second request message to the third network element, where the first condition includes one or more of the following conditions:

[0024] (1) When the first request message includes identification information of the first network and the subscription data of the second network includes identification information of one or more networks, the identification information of the one or more networks includes the identification information of the first network;

[0025] (2) When the first request message includes information indicating the location of the terminal device and the subscription data of the second network includes the service range of the second network, the service range of the second network includes the location of the terminal device.

[0026] Among them, the subscription data of the second network includes the identifiers of one or more networks, which may indicate that the terminal device can access the second network through the one or more networks, or may indicate that the terminal device whose service operator network is the one or more networks can access the second network.

[0027] In this way, the second network element manages and controls the subnet connection establishment request of the terminal device, and only sends the second request message to the third network element when the first condition is met. This can avoid the terminal device that does not meet the requirements initiating a connection establishment request to the third network element, thereby avoiding unnecessary signaling overhead.

[0028] In conjunction with the first aspect, in certain implementations of the first aspect, before sending the second request message to the third network element in the second network according to the first request message, the method further includes: obtaining the number of terminal devices that have accessed the second network; and determining that the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network. This can avoid excessive load on the second network, thereby ensuring network performance of the second network.

[0029] For example, the second network element receives the number of terminal devices that have accessed the second network from the fourth network element. The fourth network element is used to maintain the number of terminal devices that have accessed the second network, and the fourth network element may be a subnet tenant subscription function network element.

[0030] In conjunction with the first aspect, in certain implementations of the first aspect, when the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network, the method further includes: sending a message requesting an update of the number of terminal devices that have accessed the second network to a fourth network element, the fourth network element being configured to maintain the number of terminal devices that have accessed the second network. This ensures that the fourth network element promptly updates the number of terminal devices that have accessed the second network.

[0031] In combination with the first aspect, in some implementations of the first aspect, before sending the second request message to the third network element in the second network according to the first request message, the method further includes: determining that the number of terminal devices that have accessed the second network is updated successfully.

[0032] For example, the second network element receives an update response message from the fourth network element, where the update response message is used to indicate that the number of terminal devices that have accessed the second network has been updated successfully.

[0033] In combination with the first aspect, in certain implementations of the first aspect, the second response message includes the quality of service parameters corresponding to the subnet connection of the terminal device, and the quality of service parameters of the subnet connection are determined based on at least one of the following: the quality of service parameters of the terminal device or the quality of service parameters of the second network.

[0034] In combination with the first aspect, in certain implementations of the first aspect, the first response message includes the service quality parameters of the terminal device, and the subscription data of the second network includes the service quality parameters of the second network; when the service quality parameters of the terminal device and the service quality parameters of the second network meet the second condition, the service quality parameters of the subnet connection are the service quality parameters of the terminal device; or, when the service quality parameters of the terminal device and the service quality parameters of the second network do not meet the second condition, the service quality parameters of the subnet connection are the service quality parameters of the second network.

[0035] The second condition includes one or more of the following conditions:

[0036] 1) The quality of service level in the quality of service parameters of the terminal device is less than or equal to the quality of service level in the quality of service parameters of the second network;

[0037] 2) The maximum bandwidth in the quality of service parameters of the terminal device is less than or equal to the maximum bandwidth in the quality of service parameters of the second network.

[0038] In the above scheme, the second network element combines the service quality parameters of the terminal device and the service quality parameters of the second network to better determine the service quality parameters corresponding to the subnet connection of the terminal device, and can meet the service quality requirements of the terminal device as much as possible while complying with the service quality that the second network can provide.

[0039] Optionally, when the quality of service parameters of the terminal device and the quality of service parameters of the second network do not meet the second condition, the second network element sends a second response message to the first network element, and the second response message is used to indicate that the subnet connection establishment of the terminal device is not accepted.

[0040] In combination with the first aspect, in some implementations of the first aspect, the second response message includes a charging identifier, where the charging identifier is used to indicate charging for wireless resources of the first network, and the wireless resources of the first network are used to forward service data for the second network.

[0041] In conjunction with the first aspect, in certain implementations of the first aspect, the second response message includes radio resource information, where the radio resource information is used to indicate radio resources in the first network used to forward data of the service between the terminal device and the second network. In other words, the radio resources are used by the first network to support the connection between the terminal device and the second network, and the radio resources are used by the first network to forward subnet service data between the terminal device and the second network.

[0042] The wireless resource message may be determined based on subscription data of the second network. For example, the wireless resource message may be determined based on wireless resource reservation information of the first network.

[0043] In combination with the first aspect, in some implementations of the first aspect, the first request message includes first tunnel information, and the first tunnel information is used to send downlink data of the service to a first user plane network element in the first network.

[0044] In combination with the first aspect, in some implementations of the first aspect, the second request message includes the first tunnel information.

[0045] In combination with the first aspect, in some implementations of the first aspect, the first response message includes second tunnel information, and the second tunnel information is used to send uplink data of the service to a second user plane network element in the second network.

[0046] In combination with the first aspect, in some implementations of the first aspect, the second response message includes second tunnel information.

[0047] In combination with the first aspect, in some implementations of the first aspect, before sending the second request message to the third network element in the second network according to the first request message, the method further includes: acquiring address information of the third network element.

[0048] Exemplarily, the second network element obtains the address information of the third network element from locally maintained data, or the second network element receives the address information of the third network element from a fourth network element, or the second network element receives the address information of the third network element sent by a domain name server (DNS).

[0049] In a second aspect, a communication method is provided. The method may be executed by a third network element, or may be executed by a chip or circuit of the third network element, which is not limited in this application. For ease of description, the following description is based on an example of execution by the third network element.

[0050] The method includes: receiving a second request message from a second network element, the second request message is used to request the establishment of a connection between a terminal device and a second network, the second network is used to provide a service for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; determining whether to accept the establishment of the connection between the terminal device and the second network based on the second request message and the subscription data of the terminal device; and sending a first response message to the second network element, the first response message is used to indicate whether to accept the establishment of the connection between the terminal device and the second network.

[0051] The second request message may also be used to request that the terminal device access the second network.

[0052] Exemplarily, the first network is a large network operator network, such as a PLMN, also referred to as a large network or public network; the second network is a subnet, also referred to as a private network or dedicated network. The first network element is a control plane network element in the large network operator network, such as a session management network element or a mobility management network element. The second network element can be used to serve or manage the second network, or to forward messages between the first network and the second network. For example, the second network element is a sub-network agent (SNA) network element, which is used to serve or manage one or more subnets. The third network element is a control plane network element in the subnet, such as a subnet session management network element.

[0053] The service provided by the second network to the terminal device may be referred to as a subnet service, and the connection between the terminal device and the second network may be referred to as a subnet connection of the terminal device.

[0054] Exemplarily, when the third network element determines to accept the establishment of a connection between the terminal device and the second network, it sends a first response message to the second network element. The first response message can be used to indicate the acceptance of the establishment of a connection between the terminal device and the second network, to indicate that the subnet connection of the terminal device is successfully established, to indicate the acceptance of the access request of the terminal device, to indicate that the terminal device has successfully accessed, or to indicate the acceptance of the establishment of the subnet connection of the terminal device.

[0055] Exemplarily, when the third network element determines that it does not accept the establishment of a connection between the terminal device and the second network, it sends a first response message to the second network element. The first response message can be used to indicate the rejection of the establishment of a connection between the terminal device and the second network, to indicate the failure of the establishment of the connection between the terminal device and the second network, to indicate the rejection of the terminal device's access request, to indicate the failure of the terminal device's access, or to indicate the rejection of the terminal device's subnet connection establishment.

[0056] According to the solution provided in the present application, the third network element determines whether to accept the establishment of a connection between the terminal device and the second network based on the second request message and the contract data of the terminal device, so that the second network (i.e., the subnet) can realize autonomous control and management of the establishment of a connection between the terminal device and the second network, thereby reducing the complexity of deploying and maintaining the second network.

[0057] In conjunction with the second aspect, in certain implementations of the second aspect, the contract data of the terminal device is contract data created when the terminal device signs a contract with the second network. It should be understood that the contract data of the terminal device can also be updated after creation. Alternatively, the contract data of the terminal device is default contract data, which can also be referred to as default contract data. For example, when the terminal device has not yet signed a contract with the second network, the contract data of the terminal device is default contract data, and the third network element determines whether to accept the establishment of a connection between the terminal device and the second network based on the second request message and the default contract data.

[0058] In conjunction with the second aspect, in certain implementations of the second aspect, determining whether to accept establishment of a connection between the terminal device and the second network based on the second request message and the subscription data of the terminal device includes:

[0059] If the second request message and the subscription data of the terminal device meet the third condition, determine to accept the establishment of the connection between the terminal device and the second network; or, if the second request message and the subscription data of the terminal device do not meet the third condition, determine not to accept the establishment of the connection between the terminal device and the second network.

[0060] The third condition includes one or more of the following conditions:

[0061] 1) when the second request message includes information indicating the location of the terminal device, and the subscription data of the terminal device includes information indicating one or more geographical areas that the terminal device is allowed to access, the one or more geographical areas that the terminal device is allowed to access include the location of the terminal device;

[0062] 2) When the second request message includes information for indicating the logical area that the terminal device requests to access, and the subscription data of the terminal device includes information for indicating one or more logical areas that the terminal device is allowed to access, the one or more logical areas that the terminal device is allowed to access include the logical area that the terminal device requests to access.

[0063] This can prevent the terminal device from accessing geographical areas and / or logical areas that the terminal device is not allowed to access, ensure the security of the second network, and achieve autonomous management of the second network's access rights to the terminal device.

[0064] In combination with the second aspect, in certain implementations of the second aspect, the first response message is used to indicate acceptance of the connection establishment between the terminal device and the second network. Before sending the first response message to the second network element, the method also includes: determining that authentication of the terminal device is not required.

[0065] Exemplarily, when one or more of the following conditions are met, the third network element determines that authentication of the terminal device is not required:

[0066] 1) The contract data of the terminal device includes information indicating that authentication of the terminal device is not required;

[0067] 2) The second request message includes identification information allocated by the first network to the terminal device, and the identification information is credible.

[0068] For example, the second request message includes information indicating that the identification information is credible, and the third network element determines that the identification information is credible based on the information. In another example, the third network element determines that the identification information is credible based on the identification information of the terminal device being located at a specific position in the second request message.

[0069] In the above solution, the third network element does not need to authenticate the terminal device, which can reduce the processing complexity of the third network element and improve the efficiency of establishing the connection between the terminal device and the second network.

[0070] In combination with the second aspect, in certain implementations of the second aspect, the first response message is used to indicate the establishment of a connection between the receiving terminal device and the second network. Before sending the first response message to the second network element, the method also includes: successfully authenticating the terminal device.

[0071] Exemplarily, the contract data of the terminal device includes authentication information of the terminal device. The third network element authenticates the terminal device based on the authentication information. If the authentication is successful, the third network element sends a first response message to the second network element. The first response message is used to indicate the establishment of a connection between the terminal device and the second network.

[0072] In the above solution, after the third network element successfully authenticates the terminal device, it accepts the establishment of a connection between the terminal device and the second network, which can prevent illegal terminal devices from accessing the second network and improve network security.

[0073] In combination with the second aspect, in some implementations of the second aspect, the first response message includes a quality of service parameter of the terminal device, and the quality of service parameter of the terminal device is used to determine a quality of service parameter corresponding to the connection between the terminal device and the second network.

[0074] Exemplarily, the third network element determines the service quality parameters of the terminal device according to the subscription data of the terminal device, and sends the service quality parameters of the terminal device to the second network element by carrying them in the first response message.

[0075] In conjunction with the second aspect, in certain implementations of the second aspect, before determining whether to accept establishment of a connection between the terminal device and the second network based on the second request message and the subscription data of the terminal device, the method further includes: obtaining the subscription data of the terminal device. For example, the third network element sends a message requesting the subscription data of the terminal device to a fifth network element in the second network, the fifth network element being configured to manage the subscription data of terminal devices subscribed to the second network; and the third network element receives the subscription data of the terminal device from the fifth network element.

[0076] The fifth network element may be a subnet subscription and policy management network element, and the fifth network element is used to manage subscription data of subscribers of the second network and also to manage default subscription data.

[0077] Optionally, the third network element may obtain all the contract data of the terminal device at one time, or may obtain different contents of the contract data of the terminal device separately. For example, the third network element first obtains authentication-related contents in the contract data of the terminal device, such as authentication indication information and / or authentication information. If it is determined that authentication of the terminal device is not required or that authentication of the terminal device is successful based on the authentication indication information and / or authentication information, the third network element further obtains other contents of the contract data of the terminal device to determine whether the third condition is met.

[0078] In combination with the second aspect, in some implementations of the second aspect, the first response message includes second tunnel information, and the second tunnel information is used to send uplink data of the service to a second user plane network element in the second network.

[0079] In combination with the second aspect, in certain implementations of the second aspect, before sending a first response message to the second network element based on the second request message and the subscription data of the terminal device, the method also includes: sending indication information to the second user plane network element, the indication information being used to instruct the second user plane network element to allocate tunnel information for the connection; and receiving second tunnel information from the second user plane network element.

[0080] In combination with the second aspect, in some implementations of the second aspect, first tunnel information is sent to a second user plane network element in the second network, and the first tunnel information is used to send downlink data of the service to a first user plane network element in the first network.

[0081] In a third aspect, a communication method is provided. The method may be executed by a first network element, or may be executed by a chip or circuit of the first network element, which is not limited in this application. For ease of description, the following description is based on an example of execution by the first network element.

[0082] The method includes: receiving a message from a terminal device for requesting the establishment of a connection between the terminal device and a second network, the second network being used to provide a service for the terminal device, and the connection between the terminal device and the second network being used for the terminal device and the second network to transmit data of the service through the first network; sending a first request message to a second network element, the first request message being used to request the establishment of the connection; receiving a message from the second network element being used to instruct acceptance of the establishment of the connection; and sending a third request message to an access network device in the first network, the third request message being used to request allocation of wireless resources for the connection, the wireless resources being used to forward data of the service between the terminal device and the second network.

[0083] Exemplarily, the first network is a large network operator network, such as a PLMN, also referred to as a large network or public network; the second network is a subnet, also referred to as a private network or dedicated network. The first network element is a control plane network element in the large network operator network, such as a session management network element or a mobility management network element. The second network element can be used to serve or manage the second network, or to forward messages between the first network and the second network. For example, the second network element is a sub-network agent (SNA) network element, which serves or manages one or more subnets.

[0084] The first request message may also be used to request the terminal device to access the second network. The message used to request the terminal device to establish a connection with the second network may be called a connection establishment request message.

[0085] Exemplarily, the third network element sends a second request message to the second network element when triggered by the first request message.

[0086] Optionally, the connection establishment request message and the first request message include one or more of the following information: identification information of the terminal device, identification information of the second network, information indicating one or more logical areas to which the terminal device requests access, and information indicating the location of the terminal device.

[0087] Among them, the identification information of the terminal device may include the first identification information assigned to the terminal device by the first network. For example, the first network element receives the first identification information from the terminal device, such as the connection establishment request message includes the first identification information. For another example, the first network element obtains the first identification information from the contract data of the terminal device. Under this implementation method, the first identification information can be considered to be credible. The first network element can send the first identification information received from the terminal device and the first identification information obtained from the contract data of the terminal device through different positions of the first request message, so that the second network element can confirm whether the first identification information is credible based on the position of the first identification in the first request message. The first network element may also carry information for indicating whether the first identification information is credible in the first request message, so that the second network element can confirm whether the first identification information is credible based on the information.

[0088] The identification information of the terminal device may also include second identification information allocated to the terminal device by the second network, that is, the subnet subscription identification of the terminal device.

[0089] The identification information of the second network is used to indicate the second network, and the first network element and the second network element can determine that the network requested by the terminal device to access is the second network based on the identification information of the second network.

[0090] The one or more logical areas that the terminal device requests to access may be referred to as target logical areas, and the information used to indicate the target logical areas may be identification information of the target logical areas. Exemplarily, the connection establishment request message and the first request message include a first container, and the first container includes information used to indicate the target logical areas.

[0091] The information used to indicate the location of the terminal device may be user location information (ULI) of the terminal device, or an identifier of a cell in which the terminal device is currently located or a tracking area identity (TAI).

[0092] In conjunction with the third aspect, in certain implementations of the third aspect, before sending the first request message to the second network element, the method further includes: obtaining address information of the second network element. In this implementation, sending the first request message to the second network element includes: sending the first request message to the second network element based on the address information of the second network element.

[0093] Exemplarily, the first network element receives address information of the second network element from a network function repository function (NRF) network element or a DNS.

[0094] In combination with the third aspect, in certain implementations of the third aspect, the third request message includes a quality of service parameter corresponding to the connection between the terminal device and the second network, and the quality of service parameter is determined by the quality of service parameter of the terminal device and / or the quality of service parameter of the second network.

[0095] In combination with the third aspect, in certain implementations of the third aspect, the third request message includes wireless resource information, and the wireless resource information is used to determine the wireless resource.

[0096] In combination with the third aspect, in some implementations of the third aspect, the first request message includes first tunnel information, and the first tunnel information is used to send downlink data of the service to a first user plane network element in the first network.

[0097] In combination with the third aspect, in certain implementations of the third aspect, before sending the first request message to the second network element, the method also includes: sending indication information to the first user plane network element to instruct the first user plane network element to allocate downlink tunnel information for the connection; and receiving first tunnel information from the first user plane network element.

[0098] In combination with the third aspect, in some implementations of the third aspect, the third request message includes third tunnel information, and the third tunnel information is used to send uplink data of the service to the first user plane network element in the first network.

[0099] In combination with the third aspect, in certain implementations of the third aspect, before the first network element sends a third request message to the access network device, the method also includes: sending indication information to the first user plane network element to instruct the first user plane network element to allocate uplink tunnel information for the connection; and receiving third tunnel information from the first user plane network element.

[0100] In combination with the third aspect, in certain implementations of the third aspect, the method further includes: receiving fourth tunnel information from an access network device, where the fourth tunnel information is used to send downlink data of the service to the access network device.

[0101] In combination with the third aspect, in certain implementations of the third aspect, the third request message includes indication information for instructing the access network device to allocate tunnel information for the connection; receiving fourth tunnel information from the access network device includes: receiving a message from the access network device for responding to the third request message, the message including fourth tunnel information.

[0102] In a fourth aspect, a communication device is provided, which includes one or more functional units, such as a transceiver unit and a processing unit. The transceiver unit is configured to receive a first request message from a first network element in a first network, the first request message being used to request the establishment of a connection between a terminal device and a second network, the second network being used to provide a service for the terminal device, and the connection between the terminal device and the second network being used for the terminal device and the second network to transmit data of the service through the first network; the processing unit is configured to send a second request message to a third network element in the second network via the transceiver unit based on the first request message, the second request message being used to request the establishment of the connection; the transceiver unit is further configured to receive a first response message from the third network element, the first response message being used to indicate whether the establishment of the connection is accepted; and the processing unit is further configured to send a second response message to the first network element via the transceiver unit based on the first response message, the second response message being used to indicate whether the establishment of the connection is accepted.

[0103] The transceiver unit can perform the receiving and sending processing in the aforementioned first aspect and any one of its implementations, and the processing unit can perform other processing except receiving and sending in the aforementioned first aspect and any one of its implementations.

[0104] In a fifth aspect, a communication device is provided, comprising one or more functional units, such as a transceiver unit and a processing unit. The transceiver unit is configured to receive a second request message from a second network element, the second request message being used to request the establishment of a connection between a terminal device and a second network, the second network being used to provide a service for the terminal device, and the connection between the terminal device and the second network being used for the terminal device and the second network to transmit data of the service via the first network; the processing unit is configured to determine whether to accept the connection establishment based on the second request message and the subscription data of the terminal device; and the transceiver unit is further configured to send a first response message to the second network element, the first response message being used to indicate whether to accept the connection establishment.

[0105] The transceiver unit can perform the reception and transmission processing in the aforementioned second aspect and any one of its implementations, and the processing unit of the communication device can perform other processing except reception and transmission in the aforementioned second aspect and any one of its implementations.

[0106] In a sixth aspect, a communication device is provided, comprising one or more functional units, such as a transceiver unit and a processing unit. The transceiver unit is configured to receive a message from a terminal device requesting the establishment of a connection between the terminal device and a second network, the second network being configured to provide a service for the terminal device, and the connection between the terminal device and the second network being configured to transmit data of the service between the terminal device and the second network via the first network; the transceiver unit is further configured to send a first request message to a second network element, the first request message being configured to request the establishment of the connection; the transceiver unit is further configured to receive a message from the second network element indicating acceptance of the connection establishment; and the transceiver unit is further configured to send a third request message to an access network device in the first network, the third request message being configured to request allocation of wireless resources for the connection, the wireless resources being configured to forward data of the service between the terminal device and the second network.

[0107] The transceiver unit can perform the reception and transmission processing in the aforementioned third aspect and any one of its implementations, and the processing unit of the communication device can perform other processing except reception and transmission in the aforementioned third aspect and any one of its implementations.

[0108] In the seventh aspect, a communication device is provided, including a processor, the processor and a memory are coupled, the memory is used to store a computer program, and the processor is used to call and run the computer program from the memory, so that the device executes the method in the above-mentioned first to third aspects and any one of their implementation methods.

[0109] Optionally, there are one or more processors and one or more memories.

[0110] Optionally, the memory may be integrated with the processor, or the memory may be provided separately from the processor.

[0111] In an eighth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program or code, and when the computer program or code is run on a computer, the computer executes the method in the above-mentioned first to third aspects and any one of their implementations.

[0112] In a ninth aspect, a chip is provided, which includes a processor and a communication interface. The processor reads instructions stored in a memory through the communication interface to execute the methods in the above-mentioned first to third aspects and any one of their implementation methods.

[0113] Optionally, as an implementation method, the chip may also include a memory, in which instructions are stored, and the processor is used to execute the instructions stored in the memory. When the instructions are executed, the processor is used to execute the methods in the above-mentioned first to third aspects and any one of their implementation methods.

[0114] In a tenth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on the computer, executes the method of the first to third aspects and any one of their implementations.

[0115] In the eleventh aspect, a communication system is provided, including: a second network element and a third network element, the second network element is used to execute the method in the above-mentioned first aspect and any possible implementation thereof, and the third network element is used to execute the method in the above-mentioned second aspect and any possible implementation thereof.

[0116] Optionally, the communication system includes a first network element, which is used to execute the method in the above-mentioned third aspect and any one of its implementation methods.

[0117] In the twelfth aspect, a communication method is provided, including: a second network element receives a first request message from a first network element in a first network, the first request message is used to request the establishment of a connection between a terminal device and a second network, the second network is used to provide services for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; the second network element sends a second request message to a third network element in the second network according to the first request message, the second request message is used to request the establishment of the connection; the third network element receives the second request message from the second network element, and determines whether to accept the establishment of the connection according to the second request message and the contract data of the terminal device; the third network element sends a first response message to the second network element, and the first response message is used to indicate whether to accept the establishment of the connection; the second network element receives the first response message from the third network element, and sends a second response message to the first network element according to the first response message, and the second response message is used to indicate whether to accept the establishment of the connection.

[0118] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, the first request message includes identification information of the terminal device, and the second network element sends a second request message to a third network element in the second network based on the first request message, including: when the user information of the second network includes the identification information of the terminal device, the second network element sends the second request message to the third network element; wherein the user information of the second network includes identification information of one or more terminal devices allowed to establish a connection with the second network.

[0119] With reference to the twelfth aspect, in certain implementations of the twelfth aspect, the second network element sending a second request message to a third network element in the second network according to the first request message includes: if the first request message and the subscription data of the second network meet a first condition, the second network element sending the second request message to the third network element, where the first condition includes one or more of the following conditions:

[0120] (1) When the first request message includes identification information of the first network and the subscription data of the second network includes identification information of one or more networks, the identification information of the one or more networks includes the identification information of the first network;

[0121] (2) When the first request message includes information indicating the location of the terminal device and the subscription data of the second network includes the service range of the second network, the service range of the second network includes the location of the terminal device.

[0122] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, before the second network element sends a second request message to the third network element in the second network based on the first request message, the method also includes: the second network element obtains the number of terminal devices that have accessed the second network; the second network element determines that the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to access the second network at the same time.

[0123] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, when the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network, the method further includes: the second network element sends a message to the fourth network element for requesting an update of the number of terminal devices that have accessed the second network, and the fourth network element is used to maintain the number of terminal devices that have accessed the second network.

[0124] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, before the second network element sends a second request message to the third network element in the second network based on the first request message, the method also includes: the second network element determines that the number of terminal devices that have connected to the second network has been updated successfully.

[0125] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, the second response message includes the service quality parameters of the connection, and the service quality parameters of the connection are determined based on at least one of the following: the service quality parameters of the terminal device and the service quality parameters of the second network.

[0126] In conjunction with the twelfth aspect, in certain implementations of the twelfth aspect, the third network element determines whether to accept the connection establishment based on the second request message and the subscription data of the terminal device, including:

[0127] If the second request message and the subscription data of the terminal device meet the third condition, the third network element determines to accept the connection establishment; or, if the second request message and the subscription data of the terminal device do not meet the third condition, the third network element determines not to accept the connection establishment.

[0128] The third condition includes one or more of the following conditions:

[0129] 1) when the second request message includes information indicating the location of the terminal device, and the subscription data of the terminal device includes information indicating one or more geographical areas that the terminal device is allowed to access, the one or more geographical areas that the terminal device is allowed to access include the location of the terminal device;

[0130] 2) When the second request message includes information for indicating the logical area that the terminal device requests to access, and the subscription data of the terminal device includes information for indicating one or more logical areas that the terminal device is allowed to access, the one or more logical areas that the terminal device is allowed to access include the logical area that the terminal device requests to access.

[0131] In combination with the twelfth aspect, in certain implementations of the twelfth aspect, the first response message is used to indicate acceptance of the connection establishment. Before the third network element sends the first response message to the second network element, the method also includes: the third network element determines that authentication of the terminal device is not required, or the third network element successfully authenticates the terminal device.

[0132] The beneficial effects of the above-mentioned fourth to twelfth aspects and any one of their implementation methods can be referred to the relevant descriptions in the first to third aspects and their implementation methods, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0133] FIG1 is a schematic diagram of a network architecture provided in an embodiment of the present application;

[0134] FIG2 is a flow chart of a communication method 200 provided in an embodiment of the present application;

[0135] 3 is an example diagram of a method for updating the number of terminal devices that have accessed a second network provided by an embodiment of the present application;

[0136] FIG4 is a flow chart of another data transmission method 400 provided in an embodiment of the present application;

[0137] FIG5 is a schematic block diagram of a communication device 1000 provided in an embodiment of the present application;

[0138] FIG6 is a schematic block diagram of another communication device 2000 provided in an embodiment of the present application;

[0139] FIG7 is a schematic diagram of a chip system 3000 provided in an embodiment of the present application. DETAILED DESCRIPTION

[0140] The technical solutions provided in this application can be applied to various communication systems, such as new radio (NR) systems, long term evolution (LTE) systems, frequency division duplex (FDD) systems, time division duplex (TDD) systems, etc. 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 systems or other communication systems.

[0141] In the above-mentioned communication system, the part operated by the operator can be called a public land mobile network (PLMN), which is used to provide land mobile communication services. Among them, PLMN can also be called an operator network, a large network, a public network, etc., and the operator operating the PLMN can be called a large network operator. The PLMN described in the embodiments of the present application can specifically be a network that meets the requirements of the third generation partnership project (3GPP) standards, referred to as a 3GPP network. The 3GPP network includes but is not limited to the fifth generation (5G) mobile communication network, the fourth generation (4G) mobile communication network, and other future communication networks, such as the sixth generation (6G) mobile communication network.

[0142] As 3GPP networks evolve from being business-oriented (2B) to being consumer-oriented (2C), a series of emerging technologies have emerged to support the deployment of networks within designated location areas (such as enterprises, campuses, shopping malls, parks, etc.), providing customized services to users within the area, and continuously expanding the application scenarios of 3GPP networks. Among them, the network serving users within the designated location area can be called a sub-network, the designated area can be called a sub-network location, users who access the subnet within the sub-network location can be called sub-network users, and the owner of the sub-network location can be called a sub-network tenant. The subnet can also be called a private network, a dedicated network, etc., which is not limited in this application.

[0143] In existing technologies, large network operators can use shared large network resources to deploy subnets in subnet locations based on technologies such as slicing, multi-access edge computing (MEC), and local area data networks (LADN). After a subnet tenant signs a contract with a large network operator, they can use the subnet to provide services to subnet users. However, in this case, the subnet cannot independently control the access rights of subnet users to the subnet. It is usually necessary to use the unified data management (UDM) network element or policy control function (PCF) network element in the large network to add, modify, or delete subnet user access rights. Taking slicing technology as an example, the subscription data of subnet users is managed by the UDM network element of the large network. Only after the slice corresponding to the subnet is added to the subscription data can the subnet user access the subnet. Furthermore, when the subnet users are located in different locations, the subscription data of these subnet users is managed by the UDM network elements of the large network in different locations. This requires modifying the UDM network elements of the large network in different locations separately. This makes the deployment and maintenance of subnets very complicated, and limits the development of subnet scenarios.

[0144] In view of this, the present application provides a communication method, device and system to enable the subnet to autonomously manage the access rights of terminal devices to the subnet, thereby reducing the complexity and cost of subnet deployment and maintenance.

[0145] 1 is a schematic diagram of a network architecture 100 applicable to an embodiment of the present application. The network architecture 100 includes an operator network 110 , a subnet domain 120 , a subnet operator domain 130 , and a terminal device 140 .

[0146] The operator network 110 is a network deployed by a large network operator, including a (radio) access network (R)AN) 111 and a core network (CN).

[0147] The (R)AN 111 may include one or more access network elements or devices. Access network devices are nodes or devices that connect terminal device 140 to the wireless network. Access network devices may also be referred to as wireless access network devices or access network devices. The (R)AN can be considered a subnetwork of the operator's network, serving as the implementation system between service nodes and terminal devices within the operator's network. To access the operator's network, a terminal device first passes through the (R)AN, which then connects to the operator's network's service nodes. The access network device in the embodiment of the present application is a device that provides wireless communication functions for terminal devices, and may also be referred to as a network device. (R)AN devices include but are not limited to: next generation node base station (gNB) in 5G systems, evolved node B (eNB) in long term evolution (LTE), radio network controller (RNC), node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (for example, home evolved node B, or home node B, HNB), base band unit (BBU), transmission point (TRP), transmitting point (TP), small base station equipment, mobile switching center, or network equipment in future networks, etc. The access network equipment may also be a module or unit that performs the functions of a base station, such as a centralized unit (CU) and a distributed unit (DU). In a possible network structure, the CU may be used to support communications under protocols such as radio resource control (RRC), packet data convergence protocol (PDCP), and service data adaptation protocol (SDAP). The DU may be used to support communications under radio link control (RLC) layer protocols, media access control (MAC) layer protocols, and physical layer protocols. The embodiments of the present application do not limit the specific technology and specific device form used by the access network equipment.In systems using different wireless access technologies, the names of devices that function as access network devices may vary. For ease of description, in all embodiments of this application, the aforementioned devices that provide wireless communication functions for terminal devices are collectively referred to as access network devices, or simply referred to as RAN or AN. The embodiments of this application do not limit the specific type of access network devices.

[0148] The CN portion of the operator network 110 may include network elements such as a global session management (G-SM) network element 112, a global user plane (G-UP) network element 113, a global mobility management (G-MM) network element 114, and a subscription function network element 115. The G-SM network element 112, the G-MM network element 114, and the subscription function network element 115 may be referred to as control plane network elements of the operator network 110, and the G-UP network element 113 may be referred to as a user plane network element of the operator network 110. The network elements of the CN portion are briefly described below.

[0149] 1. The G-SM network element 112 can be used to establish and manage connections or sessions between terminal devices and subnets, and can also be used to count and monitor operator network resources used by terminal devices to access subnets, such as network resource usage and network resource usage duration. Exemplarily, the G-SM network element 112 can be a session management function (SMF) network element in a 5G network.

[0150] 2. The G-UP network element 113 can be used to allocate tunnel information for connections between terminal devices and subnets, forward subnet service data packets between terminal devices and subnets, and collect subnet-related billing information. The operator network 110 may include one or more G-UP network elements. FIG1 illustrates an example in which the operator network 110 includes one G-UP network element 113. For example, the G-UP network element 113 may be a user plane function (UPF) network element in a 5G network.

[0151] 3. The G-MM network element 114 can be used to authenticate and authorize access to terminal devices and can also be used to manage the mobility of terminal devices. For example, the G-MM network element 114 can be an access and mobility management function (AMF) network element in a 5G network.

[0152] 4. The subscription function network element 115 can be used to store subscription data of subscribers in the operator network 110, such as the subscriber permanent identifier (SUPI) and the general public subscription identifier (GPSI) of the subscriber, and can also be used to provide other network elements in the CN with the function of storing and obtaining subscription data. Exemplarily, the subscription function network element 115 can be a unified data management (UDM) network element or a unified data repository (UDR) network element in the 5G network, or it can integrate the functions of the UDM network element and the UDR network element.

[0153] Optionally, the CN part may also include network exposure function (NEF) network element, network function repository function (NRF) network element, policy control function (PCF) network element, application function (AF) network element, authentication server function (AUSF) network element and other network elements. For the specific functions of the above network elements, please refer to the detailed introduction in the 5G communication system, which will not be repeated here. In the embodiment of the present application, network elements may also be collectively referred to as network functions (NF).

[0154] The subnet domain 120 covers the subnet site and provides subnet services to the subnet users within the subnet site. The subnet domain 120 may include one or more of the following network elements: a sub-network subscription and policy management (SSPM) network element 121, a subnet user plane (UP) network element 122, a subnet session management (SM) network element 123, or a subnet service node 124. Among them, the SSPM network element 121 and the subnet SM network element 123 can be called the control plane network elements of the subnet domain 120, and the subnet UP network element 122 can be called the user plane network element of the subnet domain 120. The above network elements can be deployed within the subnet site, on the cloud of the subnet operator, or on a public cloud leased by the subnet operator or subnet tenant, and this application does not limit this. The network elements included in the subnet domain 120 are briefly described below.

[0155] 1. The SSPM network element 121 can be used to manage the contract data in the sub-network domain 120, such as the contract data and default contract data of the terminal devices that have signed a contract with the sub-network domain 120. It can also be used to manage the user information of the sub-network domain 120, such as the identification information of the terminal devices allowed to access the sub-network domain 120.

[0156] 2. The subnet UP network element 122 can be used to allocate tunnel information for the connection between the terminal device and the subnet domain 120 and forward user plane data between the terminal device and the subnet service node 124 within the subnet domain 120.

[0157] 3. Subnet SM network element 123 can be used to manage the access rights of terminal devices to subnet domain 120 and can also be used to establish and manage sessions or connections between terminal devices and subnet domain 120, such as establishing, maintaining, and deleting sessions or connections. This session or connection is a channel for transmitting subnet service data between the terminal device and subnet domain 120.

[0158] 4. The subnet service node 124 may be a server for providing subnet services to terminal devices, such as a web server.

[0159] Subnet operator domain 130 is a network deployed by a subnet operator. It can include one or more subnet domains and provide subnets for one or more subnet tenants. For example, in Figure 1, subnet operator domain 130 includes subnet domain 120 and subnet domain 120-1. It should be noted that the main network operator and the subnet operator can be the same or different, and this application does not impose any restrictions on this.

[0160] The sub-network operator domain 130 may include one or more of the following network elements: a sub-network agent (SNA) network element 131 and a sub-network tenant subscription function network element 132 .

[0161] 1. SNA network element 131 is a control plane network element in subnet operator domain 130 and may also be referred to as a subnet operator domain controller. SNA network element 131 manages one or more subnet domains within subnet operator domain 130, manages terminal device access to the one or more subnet domains, and acts as a signaling gateway, forwarding signaling between operator network 110 and the one or more subnet domains.

[0162] 2. The subnet tenant subscription function network element 132 may be used to store or maintain subscription information of one or more subnet domains included in the subnet operator domain 130 .

[0163] It should be noted that the subnet domain 120 and the subnet operator domain 130 may also include other network elements, and this application does not limit this. The functions of the above-mentioned network elements / devices can be completed by an independent network element / device, or by several network elements / devices together. The above-mentioned network elements or functions can be physical entities in hardware devices, or software instances running on dedicated hardware, or virtualized functions instantiated on a shared platform (for example, a cloud platform). Simply put, a network element can be implemented by hardware or by software. The above-mentioned network elements can be independent devices, or they can be integrated into the same device to implement different functions. This application does not limit the specific form of the above-mentioned network elements.

[0164] It should also be noted that the above naming is only defined to facilitate the distinction between different functions and should not constitute any limitation to this application. This application does not exclude the possibility of adopting other naming. For example, in a 6G network, some or all of the above network elements may continue to use the terminology used in 5G, or may adopt other names. For another example, a G-SM network element may also be called an operator network session management network element, a G-UP network element may also be called an operator network user plane network element, and a G-MM network element may also be called an operator network mobility management network element.

[0165] The terminal device 140 is a device that provides voice and / or data connectivity to the user. The terminal device may also be referred to as user equipment (UE). The terminal device in this application is a device with wireless transceiver capabilities that can communicate with one or more CN devices via an access network device (or may also be referred to as an access device). The terminal device may also be referred to as an access terminal, terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, user agent or user device, etc. The terminal device may be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; it may also be deployed on the water (such as a ship, etc.); it may also be deployed in the air (such as an airplane, balloon and satellite, etc.). The terminal device may be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a smart phone, a mobile phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), etc. Alternatively, the terminal device may also be a handheld device with wireless communication capabilities, a computing device, or other device connected to a wireless modem, an in-vehicle device, a wearable device, a drone device, or a terminal in the Internet of Things, the Internet of Vehicles, a 5G network, or any form of terminal in future networks, a relay user device, or a terminal in a future evolved 6G network. The relay user device may be, for example, a 5G residential gateway (RG). For example, the terminal device may be a virtual reality (VR) terminal, an augmented reality (AR) terminal, a wireless terminal in industrial control, a wireless terminal in unmanned driving, a wireless terminal in telemedicine, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, etc. The terminal device here refers to a 3GPP terminal. The embodiments of the present application do not limit the type or category of the terminal device. For ease of explanation, this application will be described below using UE as an example to refer to a terminal device.

[0166] When terminal device 140 needs to use a subnet service provided by subnet domain 120, it can access subnet domain 120 through carrier network 110 and establish a connection with subnet domain 120. Specifically, it can establish a connection with subnet service node 124 in subnet domain 120 that provides the subnet service. A connection, also referred to as a session or tunnel, is used to exchange service data between terminal device 140 and subnet domain 120 through carrier network 110. Specifically, terminal device 140 can exchange service data related to the subnet service with subnet service node 124 in subnet domain 120 through the connection. The connection between terminal device 140 and subnet domain 120 can also be referred to as a subnet connection of terminal device 140.

[0167] For example, for uplink data sent by terminal device 140 to the subnet service node of subnet domain 120, terminal device 140 can first send the data to G-UP network element 113 through (R)AN 111, and then G-UP network element 113 sends the data to subnet UP network element 122, and then subnet UP network element 122 sends the data to subnet service node 124, thereby completing the transmission of the uplink data. Similarly, for downlink data sent by the subnet service node of subnet domain 120 to terminal device 140, subnet service node 124 can send the data to terminal device 140 through subnet UP network element 122, G-UP network element 113 and (R)AN 111 in sequence.

[0168] Figure 2 is a flow chart of a communication method 200 provided in an embodiment of the present application. As shown in Figure 2, the communication method 200 can be executed by a terminal device, an access network device and a first network element, a second network element in a first network, and a third network element in a second network, or by modules and / or devices (e.g., chips or integrated circuits, etc.) with corresponding functions installed in the above-mentioned terminal device, access network device, first network element, second network element, and third network element, and this application does not limit this. For ease of description, the following description is based on the terminal device, access network device, first network element, second network element, and third network element as the execution entities. For parts not fully described, reference can be made to existing protocols.

[0169] The communication method 200 is applicable to the network architecture 100 shown in Figure 1. For example, the terminal device in Figure 2 is the terminal device 140 in Figure 1; the first network is the operator network 110 in Figure 1, the access network device is the (R)AN 111, the first network element is a control plane network element in the operator network 110, for example, the first network element is the G-SM network element 112 or the G-MM network element 114; the second network element is the SNA network element 131 in Figure 1; the second network is the subnetwork domain 120 in Figure 1, and the third network element is a control plane network element in the subnetwork domain 120, for example, the third network element is the subnetwork SM network element 123.

[0170] As shown in FIG2 , the communication method 200 includes the following steps.

[0171] S210. The terminal device sends a message to the first network element in the first network for requesting establishment of a connection between the terminal device and the second network; correspondingly, the first network element receives a message from the terminal device for requesting establishment of a connection between the terminal device and the second network.

[0172] Among them, the message used to request the establishment of a connection between the terminal device and the second network can be called a connection establishment request message, a session establishment request message, or a subnet access request message. This application does not impose any restrictions on this. The following description will be given using the connection establishment request message as an example.

[0173] The connection establishment request message may also be used to request access to a second network, or to request establishment of a connection between the terminal device and the second network. The connection establishment request message may trigger the first network element to establish a connection between the terminal device and the second network. That is, after receiving the connection establishment request message, the first network element begins to establish a connection between the terminal device and the second network. For example, after receiving the connection establishment request message, the first network element sends a second request message to the second network element.

[0174] For example, when a terminal device needs to use a service provided by the second network, the terminal device sends a connection establishment request message to the first network element. The service provided by the second network to the terminal device can be called a subnet service. The connection between the terminal device and the second network can be called the terminal device's subnet connection, which is used to transmit subnet service data between the terminal device and the second network via the first network.

[0175] The first network may be referred to as a service operator network of the terminal device, or may be referred to as an operator network that provides services to the terminal device.

[0176] Optionally, the terminal device can send a connection establishment request message directly to the first network element, or send a connection establishment request message to the first network element through other devices or network elements. For example, the terminal device can send a connection establishment request message to the first network element through an access network device in the first network.

[0177] Optionally, the connection establishment request message includes identification information of the terminal device, and the identification information of the terminal device is used to identify the terminal device, so that the first network element can identify the identity of the terminal device based on the identification information of the terminal device and determine that the terminal device initiating the connection establishment is the terminal device indicated by the identification information.

[0178] The identification information of the terminal device includes at least one of the following information: the first identification information of the terminal device or the second identification information of the terminal device. The first identification information of the terminal device is an identification assigned to the terminal device by the first network, such as when the terminal device and the first network sign a contract, the first network assigns the first identification information to the terminal device. The first identification information of the terminal device may be a mobile station international integrated services digital network number (MSISDN). The second identification information of the terminal device is an identification assigned to the terminal device by the second network, such as when the terminal device and the second network sign a contract, the second network assigns the second identification information to the terminal device. The second identification information of the terminal device may also be referred to as the subnet contract identification of the terminal device.

[0179] Optionally, the connection establishment request message includes identification information of the second network, where the identification information is used to identify the second network. The first network element can determine that the network that the terminal device requests to access is the second network based on the identification information of the second network.

[0180] Optionally, the connection establishment request message includes information indicating one or more logical areas that the terminal device requests to access, and the one or more logical areas that the terminal device requests to access are hereinafter referred to as target logical areas. For example, the connection establishment request message includes identification information of the target logical area.

[0181] The second network can include multiple logical zones, each of which can allow access to different terminal devices. A single terminal device can access one or more logical zones. For example, an enterprise campus network can be divided into green, red, and guest zones based on network security levels. All employees of the enterprise can access the green zone, but only employees with specific permissions can access the red zone. Non-employees can only access the guest zone.

[0182] Exemplarily, the connection establishment request message includes a first container, which includes information indicating the target logical area. The first container is transparently transmitted to a third network element in the second network. That is, after receiving the first container, network elements or devices other than the third network element do not parse the contents of the first container. This prevents other network elements or devices from tampering with the information and improves the security of information transmission.

[0183] S220. The first network element sends a first request message to the second network element. Correspondingly, the second network element receives the first request message from the first network element.

[0184] For example, the first network element sends the first request message to the second network element in response to the connection establishment request message from the terminal device. That is, the first network element sends the first request message to the second network element under the triggering of the connection establishment request message.

[0185] The second network element is used to manage the second network, or in other words, to serve the second network. The second network element is used to forward messages between the first network and the second network. Exemplarily, the second network element is a control plane network element (e.g., SNA network element 131) in subnet operator domain 130 in Figure 1 . In this implementation, the second network element is used to manage one or more subnet domains included in subnet operator domain 130, including subnet domain 120 (i.e., the second network); that is, the second network element serves one or more subnet domains included in subnet operator domain 130, and the second network element is used to forward messages between operator network 110 and one or more subnet domains included in subnet operator domain 130.

[0186] The first request message may be used to request establishment of a connection between the terminal device and the second network, or may be used to request access of the terminal device to the second network.

[0187] The first request message may include identification information of the terminal device, where the identification information of the terminal device includes at least one of the following information: first identification information of the terminal device or second identification information of the terminal device.

[0188] For example, the first network element carries the first identification information and / or the second identification information in the connection establishment request message in the first request message and sends it to the second network element.

[0189] For another example, the first network element obtains the first identification information of the terminal device from the subscription data of the terminal device, and sends the first identification information to the second network element in a first request message. For example, after receiving the connection establishment request message, the first network element sends a message requesting the subscription data of the terminal device to the UDM network element in the first network (such as the subscription function network element 115 in Figure 1), and receives the subscription data of the terminal device from the UDM network element, including the first identification information of the terminal device.

[0190] Optionally, the first network element determines whether to obtain the first identification information of the terminal device from the subscription data of the terminal device based on the identification information of the second network. Exemplarily, the first network element maintains a list that includes identification information of one or more subnets. When the list includes the identification information of the second network, the first network element obtains the first identification information of the terminal device from the subscription data of the terminal device. The list can be dynamically updated. For example, when the first network element receives indication information from the second network, the indication information is used to indicate that the first network is required to authenticate the terminal device requesting access to the second network, the first network element adds the identification information of the second network to the list. It can also be understood that after receiving the indication information from the second network, the first network element receives a connection establishment request message from the terminal device, authenticates the terminal device, and if the authentication is successful, obtains the first identification information of the terminal device from the subscription data of the terminal device, and sends the obtained first identification information to the second network element by carrying it in the first request message.

[0191] Under this implementation method, the second network element can consider the first identification information of the terminal device to be credible. That is, when the first identification information in the first request message is obtained by the first network element from the contract data of the terminal device, the second network element believes that the first network element has authenticated the terminal device and the authentication is successful, so the second network element does not need to authenticate the terminal device again, which can reduce the processing complexity of the second network element and improve the efficiency of the terminal device accessing the second network element.

[0192] The second network element can obtain information about whether the first identification information in the first request message is credible in different ways. Exemplarily, the second network element can determine whether the first identification information is credible based on the position of the first identification information in the first request message. For example, when the first identification information is obtained by the first network element from the connection establishment request message, the first network element places the first identification information in the first position in the first request message and sends it to the second network element; when the first identification information is obtained by the first network element from the contract data of the terminal device, the first network element places the first identification information in the second position in the first request message and sends it to the second network element, so that the second network element can determine whether the first identification information is credible based on the second position of the first identification information in the first request message. Exemplarily, the second network element can determine whether the first identification information is credible through the indication information in the first request message. For example, when the first request message includes indication information for indicating that the first identification information is credible, the second network element determines that the first identification information is credible; when the first request message does not include indication information for indicating that the first identification information is credible, the second network element considers that the first identification information is uncredible; for another example, the indication information is a bit, when the first identification information is obtained by the first network element from the connection establishment request message, the first network element sets the value of the bit to the first value (such as 0); when the first identification information is obtained by the first network element from the contract data of the terminal device, the first network element sets the value of the bit to the second value (such as 1), so that the second network element can determine that the first identification information is credible based on the value of the bit being the second value.

[0193] Optionally, the first request message includes identification information of the second network. For example, the first network element sends the connection establishment request message, along with the identification information of the second network, to the second network element in the first request message. The second network element can determine, based on the identification information of the second network, that the network requested by the terminal device is the second network.

[0194] Optionally, the first request message includes location information of the terminal device, which is used to indicate the current location of the terminal device, such as user location information (ULI) of the terminal device, or an identifier of the cell where the terminal device is currently located or a tracking area identity (TAI).

[0195] Optionally, the first request message includes identification information of the operator network serving the terminal device, that is, identification information of the first network, which may also be referred to as identification information of a serving PLMN (serving PLMN) of the terminal device.

[0196] Optionally, the first request message includes information indicating a target logical area of ​​the terminal device, such as identification information of the target logical area. Exemplarily, when the connection establishment request message includes identification information of the target logical area, the first request message includes the identification information of the target logical area. For example, the first request message includes the first container in the connection establishment request message.

[0197] Before the first network element sends the first request message to the second network element, the communication method 200 may further include: the first network element obtaining address information of the second network element. In this implementation, the first network element sends the first request message to the second network element based on the address information of the second network element. The address information of the second network element is used for communication with the second network element. For example, the address information of the second network element may be an Internet Protocol (IP) address of the second network element.

[0198] Illustratively, the first network element may adopt the following method 2.1 or method 2.2 to obtain the address information of the second network element.

[0199] Mode 2.1: The first network element receives address information of the second network element from an NRF network element in the first network.

[0200] For example, the second network element sends the identification information of the network served or managed by the second network element and the address information of the second network element to the NRF network element, where the network served or managed by the second network element includes the second network. For another example, the second network element sends the address information of the second network element and the identification information of the subnet domain in the subnet operator domain (i.e., subnet operator domain 130) where the second network element is located to the NRF network element, including the identification information of the second network. In other words, the second network element registers the identification information of the second network and the address information of the second network element with the NRF network element.

[0201] Correspondingly, the NRF network element receives the identification information of the second network and the address information of the second network element from the second network element. Further, the NRF network element can save the correspondence between the identification information of the second network and the address information of the second network element.

[0202] After receiving the identification information of the second network in the connection establishment request message, the first network element sends a first query message to the NRF network element, where the first query message includes the identification information of the second network. The first query message is used to query the address information of the second network element corresponding to the second network, that is, the first query message is used to query the address information of the second network element serving the second network, that is, the first query message is used to query the address information of the second network element in the subnet operator domain to which the second network belongs.

[0203] Correspondingly, the NRF network element receives the first query message from the first network element and searches for the address information of the second network element based on the first query message. For example, the NRF network element searches the locally stored correspondence based on the identification information of the second network in the first query message, determines the address information of the second network element corresponding to the identification information of the second network, and sends the address information of the second network element to the first network element. Correspondingly, the first network element receives the address information of the second network element from the NRF network element.

[0204] Mode 2.2: The first network element receives address information of the second network element from a domain name server (DNS).

[0205] For example, the second network element generates a first fully qualified domain name (FQDN) based on the identification information of the second network, and sends the first FQDN and the address information of the second network element to the DNS, that is, registers the first FQDN and the address information of the second network element to the DNS. For another example, in the network architecture shown in Figure 1, the subnet operator domain 130 also includes a network element #1 for operating, managing, and maintaining the subnet operator domain 130. The specific functions of network element #1 can refer to the operation, administration, and maintenance (OAM) network element in the 5G network. Network element #1 generates a first FQDN based on the identification information of the second network, or network element #1 receives the first FQDN from the second network element, and then network element #1 sends the first FQDN and the address information of the second network element to the DNS.

[0206] Correspondingly, the DNS receives the first FQDN and the address information of the second network element sent by the second network element or network element #1. Further, the DNS may store the correspondence between the address information of the second network element and the first FQDN.

[0207] After receiving the identification information of the second network in the connection establishment request message, the first network element generates a first FQDN based on the identification information of the second network, wherein the first network element generates the first FQDN in the same manner as the second network element or network element #1. The first network element sends a first query message to the DNS, where the first query message includes the first FQDN.

[0208] Correspondingly, the DNS receives the first query message from the first network element, determines the address information of the second network element corresponding to the first FQDN based on the first FQDN in the first query message and the locally stored correspondence, and sends the address information of the second network element to the first network element. Correspondingly, the first network element receives the address information of the second network element from the DNS network element.

[0209] It should be noted that the first network element may also obtain the address information of the second network element in other ways, and the embodiment of the present application does not limit this.

[0210] Optionally, the first request message includes first tunnel information. The first tunnel information is used for transmitting subnet service data of the terminal device, that is, the first tunnel information is used to send downlink data of the subnet service to the first user plane network element in the first network (such as the G-UP network element 113 in Figure 1). For example, the second user plane network element in the second network (such as the subnet UP network element 122 in Figure 1) can send the subnet service data of the terminal device to the first user plane network element based on the first tunnel information.

[0211] The first tunnel information may be allocated by the first user plane network element for the connection between the terminal device and the second network. For example, after the first network element receives the connection establishment request message from the terminal device, the communication method 200 further includes the following steps S221 and S222 (not shown in the figure):

[0212] S221. The first network element sends indication information #1 to the first user plane network element. Correspondingly, the first user plane network element receives indication information #1 from the first network element.

[0213] Indication information #1 can be used to instruct the first user plane network element to allocate tunnel information for the subnet connection of the terminal device. In other words, indication information #1 triggers the first user plane network element to allocate tunnel information for the subnet connection of the terminal device.

[0214] Before the first network element sends indication information #1 to the first user plane network element, the first network element may also select a first user plane network element from one or more user plane network elements included in the first network to support the subnet connection of the terminal device, that is, to forward subnet service data between the terminal device and the second network.

[0215] S222. In response to indication information #1, the first user plane network element sends first tunnel information allocated for the subnet connection of the terminal device to the first network element.

[0216] For example, under the triggering of indication information #1, the first user plane network element allocates first tunnel information for the subnet connection of the terminal device and sends the first tunnel information to the first network element.

[0217] Correspondingly, the first network element receives the first tunnel information from the first user plane network element, and sends the first tunnel information to the second network element by carrying it in the first request message.

[0218] S230. The second network element sends a second request message to a third network element in the second network according to the first request message. Correspondingly, the third network element receives the second request message from the second network element.

[0219] For example, if condition #1 is met, the second network element sends a second request message to a third network element in the second network. That is, if condition #1 is met, the second network element allows the terminal device to access the second network and then sends the second request message to the third network element in the second network. At this point, it can be considered that the terminal device accesses the second network through the second network element.

[0220] Among them, condition #1 includes one or more of the following conditions 3.1-3.3.

[0221] Condition 3.1: When the first request message includes identification information of the terminal device, the user information of the second network includes identification information of the terminal device, wherein the user information of the second network includes identification information of one or more terminal devices permitted to establish a connection with the second network. The identification information of the terminal device may be the first identification information of the terminal device or the second identification information of the terminal device.

[0222] Condition 3.2: The first request message and the subscription data of the second network meet the first condition, where the first condition may include one or more of the following conditions:

[0223] (1) When the first request message includes identification information of the first network and the subscription data of the second network includes a service operator network list, the service operator network list includes the identification information of the first network;

[0224] (2) When the first request message includes the location of the terminal device and the subscription data of the second network includes the service range of the second network, the service range of the second network includes the location of the terminal device.

[0225] Condition 3.3: The subscription data of the second network includes the maximum number M of terminal devices allowed to simultaneously access the second network, the number X of terminal devices that have accessed the second network is less than the maximum number M of terminal devices allowed to simultaneously access the second network, and X and M are non-negative integers.

[0226] The following is an example of how the second network element determines whether conditions 3.1-3.3 are met.

[0227] Before the second network element determines condition 3.1, the communication method 200 may further include: the second network element obtains user information of the second network. For example, the second network element may obtain user information of the second network through the following steps S231 and S232 (not shown in the figure):

[0228] S231. The second network element sends a query message #1 to the fourth network element. The query message #1 is used to query or request user information of the second network. Correspondingly, the fourth network element receives the query message #1 from the second network element.

[0229] Optionally, the query message #1 includes identification information of the second network.

[0230] For example, the second network element determines that the network that the terminal device requests to access is the second network based on the identification information of the second network in the first request message, and then sends a query message #1 to the fourth network element.

[0231] S232. In response to the query message #1, the fourth network element sends the user information of the second network to the second network element. Correspondingly, the second network element receives the user information of the second network from the fourth network element.

[0232] For example, the fourth network element determines, based on the identification information of the second network in the query message #1, that the user information corresponding to the identification information of the second network is the user information of the second network, or determines that the user information containing the identification information of the second network is the user information of the second network, and then sends the user information of the second network to the second network element.

[0233] The user information of the second network includes identification information of one or more terminal devices that are allowed to establish a connection with the second network. It can also be understood that the one or more terminal devices are terminal devices that have signed a contract with the second network element, and the one or more terminal devices are subscribed users of the second network element.

[0234] After receiving the user information of the second network from the fourth network element, the second network element determines whether condition 3.1 is satisfied.

[0235] Before the fourth network element sends the user information of the second network to the second network element, the communication method 200 may further include: a fifth network element in the second network sending the user information of the second network to the fourth network element, and correspondingly, the fourth network element receiving the user information of the second network from the fifth network element. The fifth network element may be the SSPM network element 121 in Figure 1.

[0236] For example, the fifth network element maintains user information of the second network. After the terminal device signs a contract with the second network element, the fifth network element adds the identification information of the terminal device to the user information of the second network and sends the user information of the second network to the fourth network element.

[0237] The fifth network element may directly send the user information of the second network to the fourth network element, or may indirectly send the user information of the second network to the fourth network element through other network elements. This embodiment of the present application does not impose any restrictions on this.

[0238] In another example, the fourth network element sends user information of the second network to the second network element. The user information of the second network is used to indicate that all terminal devices are allowed to access the second network. After receiving the user information of the second network from the fourth network element, the second network element can determine that all terminal devices are allowed to access the second network. In this implementation, condition 3.1 can be replaced with condition 3.1a: All terminal devices are allowed to access the second network. In other words, the second network allows unsigned terminal devices to access the second network.

[0239] Before the second network element determines condition 3.2, the communication method 200 further includes: the second network element obtains subscription data of the second network.

[0240] The subscription data of the second network may include one or more of the following information.

[0241] (1) Identification information of the second network, used to identify the second network.

[0242] (2) The service range of the second network, which may also be referred to as the coverage or service area of ​​the second network, is used to indicate the geographical area served by the second network, the cell served by the second network, or the tracking area served by the second network.

[0243] (3) The maximum number of terminal devices allowed to access the second network simultaneously, which may also be referred to as the maximum number of terminal devices supported by the second network, the maximum number of terminal devices that the second network can simultaneously serve, or the maximum number of terminal devices that can simultaneously maintain a connection with the second network.

[0244] (4) Quality of service (QoS) parameters of the second network, used to determine QoS parameters of the connection between the terminal device and the second network. The subscription data of the second network may include one or more sets of QoS parameters, where a set of QoS parameters may also be understood as a QoS profile.

[0245] Among them, a service quality profile may include one or more of the following parameters: information used to indicate the service quality level (such as 5G QoS indicator (5G QoS identifier, 5QI) or QoS class identifier (QoS class identifier, QCI)), scheduling priority, maximum bandwidth, guaranteed bandwidth, packet delay budget (packet delay budget, PDB), maximum allowed burst, allocation and retention priority (allocation and retention priority, ARP), etc. The specific meanings of the above parameters can be referred to the 3GPP standard and will not be repeated here.

[0246] (5) The service operator list may include identification information of one or more major network operators. When the identification information of a major network operator is included in the list, the terminal device can access the second network through the network of the major network operator; alternatively, when the identification information of the service operator of the terminal device is included in the list, the terminal device can access the second network.

[0247] The service operator list can also be replaced by a service operator network list, including identification information of one or more operator networks (such as PLMN identifier (ID)). When the identification information of the operator network is included in the list, the terminal device can access the second network through the operator network; or, when the identification information of the terminal device's service operator network is included in the list, the terminal device can access the second network.

[0248] The service operator / service operator network of the terminal device is the operator / operator network that provides services to the terminal device.

[0249] (6) Radio resource reservation information for one or more operator networks. The one or more operator networks are deployed by operators in the serving operator list, or the one or more operator networks are included in the serving operator network list. The radio resource reservation information for the operator network is used to indicate the radio resources reserved by the operator network for the second network. The radio resources can be used by the operator network to forward subnet service data between the terminal device and the second network.

[0250] Exemplarily, the wireless resource reservation information may include one or more of the following: a) information indicating time domain resources in the operator network; b) information indicating frequency domain resources in the operator network; c) information indicating wireless resource blocks in the operator network; d) information indicating wireless data bearers of access network equipment in the operator network.

[0251] (7) The total contracted bandwidth of the second network is used to indicate the maximum bandwidth that can be used by all terminal devices accessing the second network.

[0252] The subscription data for the second network may be created when the subnet tenant and the subnet operator sign a contract for the lease of the second network. It should be understood that the subscription data for the second network can be dynamically updated after creation. The subscription data for the second network can be managed and maintained by a fourth network element, which may be the subnet tenant subscription function network element 132 in Figure 1 . In this implementation, the second network element may obtain the subscription data for the second network by receiving the subscription data for the second network from the fourth network element. For example, the second network element may receive the subscription data for the second network from the fourth network element using a method similar to steps S231 and S232 described above.

[0253] Before determining the above condition 3.3, the communication method 200 may further include: the second network element obtaining the number X of terminal devices that have accessed the second network.

[0254] In one implementation, the second network element receives X from the fourth network element and determines whether X is less than M. The second network element may receive X from the fourth network element in any of the following manners 3.1-3.3. The second network element may also receive X from the fourth network element in other manners, which are not limited in this embodiment of the present application.

[0255] Method 3.1: The second network element sends a query message #2 to the fourth network element. Query message #2 is used to query or request X. Query message #2 may include identification information of the second network. In response, the fourth network element receives query message #2 from the second network element, determines X based on query message #2, and sends X to the second network element. The second network element can then obtain the latest X by querying the fourth network element.

[0256] Method 3.2: The fourth network element periodically sends X to the second network element. For example, the second network element sends a subscription request message #1 to the fourth network element. Subscription request message #1 is used to request a subscription to X, or subscription request message #1 is used to request the periodic push of X. In response, the fourth network element receives subscription request message #1 from the second network element and periodically sends X to the second network element based on subscription request message #1. This allows the second network element to periodically obtain X without querying the fourth network element, reducing the processing complexity of the second network element.

[0257] Method 3.3: The fourth network element sends X to the second network element when X is updated. For example, the second network element sends a subscription request message #2 to the fourth network element. Subscription request message #2 is used to request a subscription to X, or subscription request message #2 is used to request that X be sent when X is updated. Correspondingly, the fourth network element receives subscription request message #2 from the second network element and, based on subscription request message #2, sends the updated X to the second network element when X is updated. This allows the second network element to obtain the latest X without querying the fourth network element, reducing processing complexity for the second network element.

[0258] In another implementation, the second network element is SNA network element 131 (denoted as SNA network element #1) in Figure 1, and subnet operator domain 130 also includes another SNA network element (denoted as SNA network element #2). SNA network element #1 locally records the number X1 of terminal devices that have accessed the second network through SNA network element #1. For example, SNA #1 sets a counter that is used to record the number of terminal devices that have accessed the second network through SNA network element #1, and the initial value of the counter is X1 = 0. When SNA network element #1 allows the terminal device to access the second network, SNA network element #1 updates the value of the counter to X1 = X1 + 1. Similarly, SNA network element #2 locally records the number X2 of terminal devices that have accessed the second network through SNA network element #2. SNA network element #1 receives X2 from SNA network element #2. For example, SNA network element #1 receives X2 from SNA network element #2 using methods similar to those described in methods 3.1 to 3.3 above. For example, after receiving the first request message, SNA network element #1 sends a message requesting X2 to SNA network element #2, which causes SNA network element #2 to send X2 to SNA network element #1. Correspondingly, SNA network element #1 receives X2 from SNA network element #2 and adds X2 to the locally recorded X1, thereby obtaining X = X1 + X2. It should be understood that subnet operator domain 130 may also include more SNA network elements, and SNA network element #1 may use similar methods to obtain X, which will not be further described here.

[0259] After obtaining X, the second network element can determine whether X is less than M, that is, whether condition 3.3 is satisfied. Optionally, if X is equal to or greater than M, the second network element directly determines that condition 3.3 is not satisfied and thus does not send the second request message to the third network element. Alternatively, the second network element selects one or more terminal devices from the terminal devices that have already connected to the second network and disconnects the one or more terminal devices from the second network, thereby making X less than M.

[0260] For example, the user information of the second network includes identification information and corresponding priorities of one or more terminal devices permitted to establish a connection with the second network. After the second network element receives the first request message requesting establishment of a connection between terminal device #1 and the second network, if X is equal to or greater than M, the second network element selects one or more terminal devices with a lower priority than terminal device #1 based on the user information of the second network. The second network element then sends information instructing the one or more terminal devices to disconnect from the second network, or sends information instructing the one or more terminal devices to disconnect from the second network to a third network element, such that X is less than M. It should be understood that the embodiments of the present application do not limit how the second network element selects the terminal devices to disconnect from the second network. For example, the second network element may determine whether to disconnect the terminal device from the second network based on factors such as the connection duration between the terminal device and the second network and the data transmission load. It should also be understood that the second network element may trigger the fourth network element or the third network element to select one or more terminal devices from among the terminal devices already connected to the second network and disconnect the one or more terminal devices from the second network. This embodiment of the present application does not limit this.

[0261] Optionally, when the second network element determines that X is less than M, the second network element sends an update request message to the fourth network element, where the update request message is used to request updating X. In this implementation, condition 3.3 can be replaced by: when X is less than M and X is updated successfully.

[0262] Correspondingly, the fourth network element receives the update request message from the second network element and updates X according to the update request message. For example, the fourth network element updates X to X+1. Optionally, the fourth network element updates X according to the update request message if the updated X is less than or equal to M. That is, before updating X according to the update request message, the fourth network element determines whether the updated X would be less than or equal to M if X were updated. For example, if X+1 is less than or equal to M, the fourth network element updates X to X+1; if X+1 is greater than M, X is not updated.

[0263] Optionally, the fourth network element sends an update response message to the second network element to indicate a result of updating X. For example, when the fourth network element completes updating X (such as when X+1 is less than or equal to M), the update response message is used to indicate that the update is complete or successful; or, when the fourth network element does not update X (such as when X+1 is greater than M), the update response message is used to indicate that the update failed or was rejected. The update response message may further include a cause value, such as a cause value indicating that the maximum number of terminal devices allowed to simultaneously access the second network has been exceeded.

[0264] Correspondingly, the second network element receives the update response message from the fourth network element, determines whether X is updated successfully according to the update response message, and then determines whether to send the second request message to the third network element.

[0265] When the second network element sends an update request message to the fourth network element and does not receive an update response message from the fourth network element within a specified time period, the second network element may assume that the update has failed and not send the second request message to the third network element. For example, after sending the update request message to the fourth network element, the second network element starts a timer. When the timer times out and the second network element has not received an update response message from the fourth network element, the second network element assumes that the update has failed. The timer value may be specified by the protocol, negotiated between the second network element and the fourth network element, or configured by the system, and this embodiment of the present application does not impose any restrictions on this.

[0266] Alternatively, when the second network element sends an update request message to the fourth network element and does not receive an update response message from the fourth network element within a specified time period, the second network element may assume that the update is successful. Specific implementation methods can be referred to the above description and will not be repeated here.

[0267] The second network element determines whether to send a second request message to the third network element based on the X update result to avoid conflicts. As shown in Figure 3, the second network element is SNA network element 131 (denoted as SNA network element #1) in Figure 1, subnet operator domain 130 also includes another SNA network element (denoted as SNA network element #2), and the fourth network element is subnet tenant subscription function network element 132. For example, if X = 4 and M = 5, after receiving a message requesting access to the second network for terminal device #1, SNA network element #1 sends a query message #2 to subnet tenant subscription function network element 132 to request X. Subnet tenant subscription function network element 132 sends X = 4 to SNA network element #1. SNA network element #1 determines that X is less than M and sends an update request message to subnet tenant subscription function network element 132. Subnet tenant subscription function network element 132 updates X to X = 5 based on the update request message and sends an update response message to SNA network element #1 indicating that the X update was successful. Then, SNA network element #1 may send a second request message to the third network element to advance the process of connecting terminal device #1 to the second network.

[0268] Similarly, after receiving the message requesting access to the second network for terminal device #2, SNA network element #2 sends a query message #2' to subnet tenant subscription function network element 132, requesting X. If subnet tenant subscription function network element 132 receives query message #2' before receiving the update request message from SNA network element #1, it will send X=4 to SNA network element #2. SNA network element #2 determines that X is less than M and also sends an update request message to subnet tenant subscription function network element 132. At this point, subnet tenant subscription function network element 132 has already updated X to X=5 based on the update request message from SNA network element #1. Since X+1 is greater than M, subnet tenant subscription function network element 132 sends a message to SNA network element #2 indicating that the update of X failed, and SNA network element #2 will not allow terminal device #2 to access the second network. This can prevent the number of terminal devices simultaneously accessing the second network from exceeding the maximum number of terminal devices supported by the second network after both terminal device #1 and terminal device #2 access the second network, thereby reducing the possibility of network congestion and ensuring network performance.

[0269] Optionally, the above condition 3.3 may be replaced by condition 3.3a: the number Y of terminal devices that have accessed the second network through the second network element is less than the maximum number N of terminal devices permitted to access the second network through the second network element, where Y and N are non-negative integers. In this implementation, the communication method 200 may further include: the second network element obtaining the maximum number N of terminal devices permitted to access the second network through the second network element.

[0270] For example, the fourth network element sends N to the second network element, and correspondingly, the second network element receives N from the fourth network element, where N can be determined based on the maximum number M of terminal devices allowed to access the second network simultaneously in the subscription data of the second network.

[0271] Below, taking the second network element as SNA network element 131 (denoted as SNA network element #1) in Figure 1, the subnet operator domain 130 also includes another SNA network element (denoted as SNA network element #2), and the fourth network element is the subnet tenant signing function network element 132 as an example, an exemplary implementation method of the second network element determining whether condition 3.3a is satisfied is explained.

[0272] The subnet tenant signing function network element 132 sends first quota information to the SNA network element #1, where the first quota information is used to indicate that the maximum number of terminal devices allowed to access the second network through the SNA network element #1 is N; similarly, the subnet tenant signing function network element 132 sends second quota information to the SNA network element #2, where the second quota information is used to indicate that the maximum number of terminal devices allowed to access the second network through the SNA network element #2 is N', where N and N' are non-negative integers, and the sum of N and N' is less than or equal to M.

[0273] SNA network element #1 locally records the number Y of terminal devices that access the second network through SNA network element #1. For example, after initial instantiation or after receiving the first quota information, SNA network element #1 sets an initial value Y=0 for a counter used to record the number of terminal devices that access the second network through SNA network element #1. When SNA network element #1 permits the terminal device to access the second network, SNA network element #1 updates the value of the counter to Y=Y+1.

[0274] When SNA network element #1 determines whether condition 3.3a is satisfied, SNA network element #1 queries the locally recorded value Y to determine whether Y is less than N. If Y is less than N, SNA network element #1 determines that condition 3.3a is satisfied; if Y is equal to or greater than N, SNA network element #1 determines that condition 3.3a is not satisfied.

[0275] Optionally, when Y is equal to or greater than N, SNA network element #1 may also send a message to the subnet tenant signing function network element 132 for requesting an increase in quota. The message for requesting an increase in quota may include the requested increase in quota n. When the message for requesting an increase in quota does not include the requested increase in quota n, it may indicate that the requested increase in quota is 1.

[0276] Correspondingly, the subnet tenant signing function network element 132 receives a message from the SNA network element #1 requesting an increase in the quota, and based on the message, sends a response message to the SNA network element #1. The response message is used to indicate that the quota increase is successful, or the response message is used to indicate a refusal to increase the quota or a failure to increase the quota.

[0277] For example, when N+n+N' is less than or equal to M, the subnet tenant contracting function network element 132 sends a response message to the SNA network element #1 to indicate that the quota increase is successful. Optionally, the response message includes the increased quota number n. For another example, when N+n+N' is greater than M, the subnet tenant contracting function network element 132 sends a response message to the SNA network element #1 to indicate that the quota increase is rejected or the quota increase fails. For another example, when N+n'+N' is less than or equal to M, regardless of whether N+n+N' is greater than M, the subnet tenant contracting function network element 132 may send a response message to the SNA network element #1 including the increased quota number n'. The response message is used to indicate that the quota number that the SNA network element #1 can increase is n'.

[0278] Next, SNA network element #1 receives the response message from subnet tenant subscription function network element 132, and determines whether condition 3.3a is satisfied based on the response message.

[0279] For example, when the response message indicates a rejection of the quota increase or a failure to increase the quota, SNA network element #1 determines that condition 3.3a is not satisfied. When the response message indicates a successful quota increase, SNA network element #1 determines that condition 3.3a is satisfied. When the response message includes the increased quota number n (or n'), SNA network element #1 may update N=N+n (or N=N+n').

[0280] When condition #1 includes multiple conditions among the above-mentioned condition 3.1 (or condition 3.1a), condition 3.2, and condition 3.3 (or condition 3.3a), the embodiment of the present application does not limit the order in which the second network element judges the multiple conditions. For example, the second network element first obtains the user information of the second network, judges condition 3.1 (or condition 3.1a), and when condition 3.1 (or condition 3.1a) is met, obtains the subscription data of the second network, and judges condition 3.2 and / or condition 3.3. For another example, the second network element first judges condition 3.3a, and when condition 3.3a is met, obtains the user information of the second network and the subscription data of the second network, and judges condition 3.1 (or condition 3.1a) and / or condition 3.2. This can avoid the second network element from unnecessarily obtaining the user information of the second network and / or the subscription data of the second network, thereby reducing signaling overhead and improving resource utilization.

[0281] The user information of the second network and the subscription data of the second network can be carried in the same message and sent to the second network element, or can be carried in different messages and sent to the second network element. The embodiment of the present application does not limit this. Optionally, the subscription data of the second network includes the user information of the second network, so that the second network element can obtain the user information of the second network and the subscription data of the second network at the same time, thereby improving the efficiency of information transmission and simplifying the process. In this implementation method, when the user information of the second network in the subscription data of the second network is missing, it can indicate that all terminal devices are allowed to access the second network, that is, the second network allows unsigned terminal devices to access the second network. At this time, the second network element can consider that condition 3.1a is met.

[0282] The number X of terminal devices that have accessed the second network and the user information of the second network can be carried in the same message and sent to the second network element, or they can be carried in different messages and sent to the second network element. This embodiment of the present application does not impose any restrictions on this. For example, the above-mentioned query message #1 and query message #2 can be a request message, that is, the second network element simultaneously requests the user information and X of the second network from the fourth network element, and the fourth network element sends the user information and X of the second network to the second network element through the same message. Similarly, the number X of terminal devices that have accessed the second network and the contract data of the second network can be carried in the same message and sent to the second network element, or they can be carried in different messages and sent to the second network element. No further details will be given here.

[0283] In another implementation, the second network element receives information indicating that the terminal device is allowed to access the second network, and then sends a second request message to the third network element. Exemplarily, the second network element receives information indicating that the terminal device is allowed to access the second network from a fourth network element. For example, after receiving the first request message, the second network element forwards the information in the first request message (such as the terminal device's identification information, the second network's identification information, the terminal device's location information, the first network's identification information, etc.) to the fourth network element. Correspondingly, the fourth network element receives the information in the first request message from the second network element and, based on the information, determines whether to allow the terminal device to access the second network. The fourth network element may determine whether to allow the terminal device to access the second network based on condition #1 above, or may determine whether to allow the terminal device to access the second network based on other conditions or local configuration. If it is determined that the terminal device is allowed to access the second network (such as condition #1 is met), the fourth network element sends information indicating that the terminal device is allowed to access the second network to the second network element. If it is determined that the terminal device is not allowed to access the second network (such as condition #1 is not met), the fourth network element may send information to the second network element indicating that the terminal device is not allowed to access the second network or that the terminal device is denied access to the second network. The implementation method of the fourth network element determining whether to allow the terminal device to access the second network according to condition #1 can refer to the above description of the second network element judgment condition #1, which will not be repeated here.

[0284] Optionally, before the second network element sends the second request message to the third network element in the second network according to the first request message, the communication method 200 further includes: the second network element obtaining address information of the third network element. Exemplarily, the second network element may obtain the address information of the third network element using one of the following methods 3.4-3.7.

[0285] Mode 3.4: The second network element obtains the address information of the third network element from locally maintained data.

[0286] For example, the second network element locally stores the correspondence between the identification information of the second network and the address information of the third network element. The second network element determines the address information of the third network element according to the identification information of the second network in the first request message and the above correspondence.

[0287] Mode 3.5: The second network element receives the address information of the third network element from the fourth network element.

[0288] For example, the second network element receives subscription data of the second network from the fourth network element, where the subscription data of the second network includes address information of the third network element.

[0289] For another example, the fourth network element sends the subscription data of the second network and the address information of the third network element to the second network element in response to the message sent by the second network element to request the subscription data of the second network. The address information of the third network element and the subscription data of the second network can be included in the same message or in different messages.

[0290] For another example, before the second network element sends the second request message to the third network element, the second network element sends a message to the fourth network element requesting the address information of the third network element, where the message may include identification information of the second network. In response, the fourth network element receives the message from the second network element requesting the address information of the third network element, and based on the message, for example, based on the identification information of the second network in the message, obtains the address information of the third network element from locally maintained data, and sends the address information of the third network element to the second network element.

[0291] Mode 3.6: The second network element receives the address information of the third network element sent by network element #2.

[0292] For example, the subnet operator domain 130 in Figure 1 also includes a network element #2, which can be used to maintain real-time information of network functions and services in the subnet operator domain 130. The specific functions can be referred to the NRF network element in the 5G system, which will not be repeated here.

[0293] For example, the third network element or network element #1 sends the address information of the third network element and the identification information of the second network to network element #2. Correspondingly, network element #2 receives the identification information of the second network and the address information of the third network element from the third network element or network element #1. Furthermore, network element #2 can store the correspondence between the identification information of the second network and the address information of the third network element. Network element #1 is used to operate, manage, and maintain the subnet operator domain 130. The specific functions of network element #1 can refer to the OAM network element in the 5G network.

[0294] Before the second network element sends the second request message to the third network element, the second network element sends a message to network element #2 for querying the address information of the third network element, the message including the identification information of the second network. In response, network element #2 receives the message from the second network element for querying the address information of the third network element, determines the address information of the corresponding third network element based on the identification information of the second network in the message, and sends the address information of the third network element to the second network element.

[0295] Mode 3.7: The second network element receives the address information of the third network element sent by the DNS.

[0296] For example, the third network element or network element #1 generates a second FQDN based on the identification information of the second network and sends the second FQDN and the address information of the third network element to the DNS, thereby registering the second FQDN and the address information of the third network element with the DNS. In response, the DNS receives the second FQDN and the address information of the third network element sent by the third network element. Furthermore, the DNS may also store the correspondence between the address information of the third network element and the second FQDN.

[0297] Before the second network element sends the second request message to the third network element, the second network element generates a second FQDN based on the identification information of the second network, and sends a message to the DNS for querying the address information of the third network element, where the message includes the second FQDN, wherein the second network element generates the second FQDN in the same way as the third network element generates the second FQDN.

[0298] Correspondingly, the DNS receives a message from the second network element for querying the address information of the third network element, and determines the address information of the third network element based on the second FQDN in the message. For example, based on the second FQDN in the message and the locally stored correspondence, the DNS determines the address information of the third network element corresponding to the second FQDN. Next, the DNS sends the address information of the third network element to the second network element.

[0299] The second request message may be used to request the terminal device to access the second network, or may be used to request establishment of a connection between the terminal device and the second network, that is, may be used to request establishment of a connection between the terminal device and the second network.

[0300] Optionally, the second request message includes identification information of the terminal device. The identification information of the terminal device may be first identification information of the terminal device or second identification information of the terminal device.

[0301] Optionally, the second request message includes the location information of the terminal device. Exemplarily, when the first request message includes the location information of the terminal device, the second network element carries the location information of the terminal device in the second request message and sends it to the third network element.

[0302] Optionally, the second request message includes identification information of the serving PLMN of the terminal device, that is, identification information of the first network. For example, the identification information of the first network may be carried in the first request message, or may be obtained by the second network element according to the source address of the first request message.

[0303] When the location information of the terminal device is the identifier of the cell where the terminal device is currently located or TAI, since the cell identifier and TAI identifier are unique within the PLMN, the third network element can combine the location information of the terminal device and the identifier information of the first network to uniquely determine the current location of the terminal device.

[0304] Optionally, the second request message includes information indicating a target logical area of ​​the terminal device, such as identification information of the target logical area. Exemplarily, if the first request message includes identification information of the target logical area, the second request message includes the identification information of the target logical area. For example, the second request message includes the first container in the first request message.

[0305] In the case where the first request message includes the first tunnel information allocated by the first user plane network element for the subnet connection of the terminal device, the second request message also includes the first tunnel information. For example, the second network element carries the first tunnel information in the first request message in the second request message and sends it to the third network element.

[0306] Optionally, when the second network element does not meet condition #1, the communication method 200 further includes the following steps S233 and S234 (not shown in the figure):

[0307] S233. The second network element sends a response message #1 to the first network element. Correspondingly, the first network element receives the response message #1 from the second network element.

[0308] Response message #1 is used to indicate that the terminal device is denied access to the second network, to indicate that the terminal device has failed to access the second network, or to indicate that the connection between the terminal device and the second network has failed. Optionally, response message #1 includes a reason value indicating the reason for denying the terminal device access to the second network.

[0309] S234. In response to response message #1, the first network element sends a connection establishment response message to the terminal device. Correspondingly, the terminal device receives the connection establishment response message from the first network element.

[0310] The connection establishment response message is used to indicate that the terminal device is denied access to the second network, to indicate that the terminal device has failed to access the second network, or to indicate that the connection establishment between the terminal device and the second network has failed. The terminal device can determine that the request to access the second network has been denied based on the connection establishment response message. Optionally, the connection establishment response message includes a cause value, which is used to indicate the reason for denying the terminal device access to the second network. For example, the first network element carries the cause value in response message #1 in the connection establishment response message and sends it to the terminal device.

[0311] S240. The third network element determines whether to accept the establishment of a connection between the terminal device and the second network according to the second request message and the subscription data of the terminal device.

[0312] The subscription data of the terminal device may be the subscription data created when the terminal device signs a contract with the second network. It should be understood that the subscription data of the terminal device may be dynamically updated after creation. The subscription data of the terminal device may also be the default subscription data.

[0313] Before the third network element determines whether to accept the establishment of a connection between the terminal device and the second network according to the second request message and the subscription data of the terminal device, the communication method 200 may further include: the third network element obtains the subscription data of the terminal device.

[0314] For example, the third network element receives the subscription data of the terminal device from the fifth network element. The fifth network element may be the SSPM network element 121 in Figure 1 , and is configured to maintain user subscription data of the second network, including subscription data of terminal devices subscribed to the second network and / or default subscription data. For example, if the second network allows unsubscribed terminal devices to access the second network, the fifth network element maintains the default subscription data.

[0315] Exemplarily, the third network element sends a query message #3 to the fifth network element. Query message #3 is used to query or request the subscription data of the terminal device. Optionally, query message #3 includes identification information of the terminal device. Accordingly, the fifth network element receives query message #3, obtains the subscription data of the terminal device based on query message #3, and sends the subscription data of the terminal device to the third network element.

[0316] In one implementation, the terminal device has already signed a contract with the second network, and the fifth network element maintains the contract data created when the terminal device signed the contract with the second network. Based on the identification information of the terminal device in query message #3, the fifth network element determines that the contract data corresponding to the identification information of the terminal device is the contract data of the terminal device, or determines that the contract data including the identification information of the terminal device is the contract data of the terminal device.

[0317] In another implementation, the fifth network element sends default subscription data to the third network element based on the terminal device's identification information in query message #3. For example, the fifth network element determines that the terminal device is not subscribed to the second network, and therefore sends the default subscription data to the third network element. The fifth network element may determine that the terminal device is not subscribed to the second network if it fails to find subscription data corresponding to the terminal device's identification information, or fails to find subscription data containing the terminal device's identification information. Accordingly, the third network element receives the default subscription data sent by the fifth network element and uses the default subscription data as the subscription data for the terminal device.

[0318] The contract data of the terminal device includes any one or more of the following information.

[0319] (1) Terminal device identification information: used to identify the terminal device, which can be the first identification information of the terminal device or the second identification information of the terminal device. It should be noted that the default contract data does not include the terminal device identification.

[0320] (2) Authentication indication information: used to indicate whether the second network needs to authenticate the terminal device.

[0321] (3) Authentication information: including information related to the authentication of the terminal device, such as the authentication key and authentication method (such as extensible authentication protocol authentication and key agreement (EAP AKA), certificate-based authentication) used to authenticate the terminal device. It should be noted that when the authentication indication information indicates that the second network needs to authenticate the terminal device, the contract data of the terminal device may also include authentication information. When the authentication indication information indicates that the second network does not need to authenticate the terminal device, the contract data of the terminal device does not include authentication information. It should also be noted that when the second network needs to authenticate the terminal device, the contract data of the terminal device may only include authentication information, but not authentication indication information. That is, the third network element may determine that the terminal device needs to be authenticated based on the fact that the contract data of the terminal device includes authentication information. The authentication information in the default contract data does not include the authentication key, and the authentication method may be certificate-based authentication.

[0322] (4) Access permission information: used to indicate the subnet areas that terminal devices are allowed and / or prohibited from accessing.

[0323] The access permission information may include logical area restriction information for indicating a logical area that the terminal device is allowed to access, and / or the logical area restriction information is used to indicate a logical area that the terminal device is prohibited from accessing.

[0324] The following is an exemplary description of the representation of the logical area restriction information.

[0325] Example 4.1: The logical area restriction information includes identifiers corresponding to logical areas that the terminal device is allowed to access, and / or the logical area restriction information includes identifiers corresponding to logical areas that the terminal device is prohibited from accessing.

[0326] Example 4.2: Logical area restriction information includes identifiers of each logical area of ​​the second network, and indication information corresponding to the identifiers of each logical area, the indication information being used to indicate whether the terminal device is allowed to access the corresponding logical area. Optionally, the indication information is a bit. When the bit takes a first value (e.g., 1), it indicates that the terminal device is allowed to access the corresponding logical area. When the bit takes a second value (e.g., 0), it indicates that the terminal device is prohibited from accessing the corresponding logical area. For example, Table 1 is the logical area restriction information of terminal device 140, indicating that terminal device 140 is allowed to access logical areas #a and #c, and is prohibited from accessing logical area #b.

[0327] Table 1

[0328] Example 4.3: The second network includes multiple logical areas of different levels, each level of logical area includes one or more logical areas, and the logical area restriction information is used to indicate the level of logical areas that the terminal device is allowed to access, or the logical area restriction information is used to indicate the highest level / lowest level of logical areas that the terminal device is allowed to access.

[0329] For example, the second network includes logical area #a, logical area #b, and logical area #c, where the level of logical area #a is 1, the level of logical area #b is 2, and the level of logical area #c is 3. When the logical area restriction information indicates that the logical area level allowed for access by the terminal device is 1, the terminal device is allowed to access logical area #a, and the terminal device is prohibited from accessing logical area #b and logical area #c. When the logical area restriction information indicates that the highest level of the logical area allowed for access by the terminal device is 2, the terminal device is allowed to access logical area #a and logical area #b, and the terminal device is prohibited from accessing logical area #c.

[0330] The access permission information may also include subnet geographic area restriction information. The coverage of the second network may include multiple subnet geographic areas. Different subnet geographic areas may allow different terminal devices to access. The same terminal device may access one or more subnet geographic areas. The above-mentioned geographic areas may be cells or tracking areas.

[0331] The subnet geographic area restriction information is used to indicate one or more subnet geographic areas that a terminal device is allowed to access, and / or the logical area restriction information is used to indicate one or more subnet geographic areas that a terminal device is prohibited from accessing. For examples of subnet geographic area restriction information, refer to the description of logical area restriction information and are not repeated here.

[0332] It should be understood that the access permission information may include both logical area restriction information and subnet geographic area restriction information. For example, if the logical area restriction information indicates that the logical area allowed to be accessed by the terminal device is a green zone, and the subnet geographic area restriction information indicates that the subnet geographic area allowed to be accessed by the terminal device is a gymnasium, then the terminal device can access the network in the green zone covering the gymnasium.

[0333] (5) QoS parameters of the terminal device: The subscription data of the terminal device may include one or more sets of QoS parameters. Each set of QoS parameters includes, but is not limited to, one or more of the following information: information indicating the QoS level (such as 5QI or QCI), scheduling priority, maximum allowed bandwidth, preemption priority, etc. The specific introduction of the above QoS parameters can be referred to in the existing protocols and will not be repeated here. The above set of QoS parameters can be referred to as a QoS profile, and the subscription data of the terminal device may include the identifier of the one or more QoS profiles.

[0334] The third network element determines whether to accept the establishment of a connection between the terminal device and the second network: if condition #2 is met, the third network element determines to accept the establishment of a connection between the terminal device and the second network, that is, the third network element determines to accept the terminal device's access to the second network; if condition #2 is not met, the third network element determines not to accept the establishment of a connection between the terminal device and the second network, that is, the third network element determines to reject the terminal device's access to the second network.

[0335] Among them, condition #2 includes one or more of the following conditions 4.1 and 4.2.

[0336] Condition 4.1: The second request message and the subscription data of the terminal device meet the third condition, where the third condition includes one or more of the following conditions.

[0337] Condition 4.1.1: The second request message includes the location of the terminal device, and the subscription data of the terminal device includes information indicating one or more geographical areas that the terminal device is allowed to access, and the one or more geographical areas that the terminal device is allowed to access include the location of the terminal device.

[0338] For example, the second request message includes location information of the terminal device, and the subscription data of the terminal device includes subnet geographic area restriction information, where the subnet geographic area restriction information is used to indicate one or more subnet geographic areas that the terminal device is allowed to access. The third network element determines, based on the location information of the terminal device and the subnet geographic area restriction information, that the current location of the terminal device belongs to a geographic area that the terminal device is allowed to access.

[0339] The above condition 4.1.1 can also be replaced by that the second request message includes the location of the terminal device, and the subscription data of the terminal device includes information for indicating one or more geographical areas that the terminal device is prohibited from accessing, and the one or more geographical areas that the terminal device is prohibited from accessing do not include the location of the terminal device.

[0340] Condition 4.1.2: The second request message includes information for indicating the logical area to which the terminal device requests access, and the subscription data of the terminal device includes information for indicating one or more logical areas in the second network that the terminal device is allowed to access, and the one or more logical areas that the terminal device is allowed to access include the logical area that the terminal device requests access.

[0341] For example, the second request message includes information for indicating a target logical area of ​​the terminal device, and the subscription data of the terminal device includes logical area restriction information, where the logical area restriction information is used to indicate one or more logical areas to which the terminal device is allowed to access. The third network element determines that the target logical area of ​​the terminal device belongs to a logical area to which the terminal device is allowed to access.

[0342] The above condition 4.1.2 can also be replaced by that the second request message includes information for indicating the logical area to which the terminal device requests access, and the subscription data of the terminal device includes information for indicating one or more logical areas in the second network that are prohibited for the terminal device to access, and the one or more logical areas that are prohibited for the terminal device to access do not include the logical area that the terminal device requests access.

[0343] Condition 4.2: The terminal device does not need to be authenticated, or the terminal device is successfully authenticated.

[0344] For example, the third network element determines whether the terminal device needs to be authenticated, and if it is determined that the terminal device needs to be authenticated, authenticates the terminal device.

[0345] Illustratively, when any one of the following conditions 4.2.1-4.2.3 is met, the third network element determines that the terminal device does not need to be authenticated; when none of the following conditions 4.2.1-4.2.3 is met, the third network element determines that the terminal device needs to be authenticated.

[0346] Condition 4.2.1: The contract data of the terminal device includes authentication indication information, and the authentication indication information indicates that the terminal device does not need to be authenticated; or the contract data of the terminal device does not include authentication indication information indicating that the terminal device needs to be authenticated; or the contract data of the terminal device does not include authentication information;

[0347] Condition 4.2.2: The second request message includes the first identification information of the terminal device, and the first identification information is authentic;

[0348] The implementation manner in which the third network element determines whether the first identification information of the terminal device is credible may refer to the description in step S220 and will not be repeated here.

[0349] Condition 4.2.3: The second network does not need to authenticate any terminal device that requests to access the second network.

[0350] Optionally, when the subscription data of the terminal device includes authentication information, the third network element authenticates the terminal device according to the authentication information. Exemplarily, the third network element authenticates the terminal device according to the authentication key in the authentication information and the authentication method indicated in the authentication information.

[0351] The third network element can obtain all the subscription data of the terminal device at one time, or it can obtain different contents of the subscription data of the terminal device separately. For example, the third network element first obtains the authentication content in the subscription data of the terminal device, such as authentication indication information and / or authentication information, and determines whether condition 4.2 is met. If not, the third network element determines that the connection between the terminal device and the second network is not accepted. If it is met, the third network element further obtains other contents in the subscription data of the terminal device, such as access permission information, and determines whether condition 4.1 is met. This can prevent the third network element from obtaining unnecessary subscription data content.

[0352] S250. The third network element sends a first response message to the second network element. The first response message is used to indicate whether to accept the establishment of a connection between the terminal device and the second network.

[0353] For example, when the third network element determines to accept the establishment of a connection between the terminal device and the second network, the third network element sends a first response message to the second network element. The first response message is used to indicate the acceptance of the connection establishment. It should be understood that the first response message can also be used to indicate the successful establishment of the connection, to indicate the acceptance of the access request of the terminal device, to indicate the successful access of the terminal device, or to indicate the establishment of the subnet connection of the terminal device.

[0354] For another example, when the third network element determines that it does not accept the establishment of a connection between the terminal device and the second network, the third network element sends a first response message to the second network element. The first response message is used to indicate the rejection of the connection establishment. It should be understood that the first response message can also be used to indicate the failure of the connection establishment, to indicate the rejection of the access request of the terminal device, to indicate the failure of the terminal device to access, or to indicate the rejection of the subnet connection establishment of the terminal device.

[0355] Optionally, when the third network element determines to accept the establishment of a connection between the terminal device and the second network, the first response message includes one or more of the following information: information indicating the logical area to which the terminal device is allowed to access, second tunnel information, or QoS parameters of the terminal device. For example, when condition #2 includes condition 4.1.2, and the second request message and the subscription data of the terminal device do not meet condition 4.1.2, the third network element determines the logical area to which the terminal device is allowed to access based on the logical area restriction information in the subscription data of the terminal device, and carries the identifier of the determined logical area in the first response message.

[0356] Optionally, when the contract data of the terminal device includes logical area restriction information, and the second request message does not include information for indicating the target logical area of ​​the terminal device, the third network element may determine the logical area that the terminal device is allowed to access based on the logical area restriction information, and carry the identifier of the determined logical area in the first response message.

[0357] For example, the first response message includes a second container, which includes information indicating the logical area to which the terminal device is allowed to access, such as an identifier of the logical area to which the terminal device is allowed to access. The second container will be transparently transmitted to the terminal device. That is, after receiving the second container, network elements or devices other than the terminal device will not parse the contents of the second container.

[0358] The second tunnel information is used for transmitting subnet service data of the terminal device, that is, the second tunnel information is used to send uplink data of the subnet service to the second user plane network element, and the first user plane network element can send subnet service data to the second user plane network element according to the second tunnel information.

[0359] The second tunnel information may be allocated by a second user-plane network element in the second network (such as subnet UP network element 122 in FIG. 1 ) for the subnet connection of the terminal device. Exemplarily, before the third network element sends the first response message to the second network element, the communication method 200 further includes: the third network element sending indication information #2 to the second user-plane network element, and the second user-plane network element correspondingly receives the indication information #2 from the third network element.

[0360] The indication information #2 may be used to indicate allocation of tunnel information for a subnet connection of a terminal device, or the indication information #2 may be used to request establishment of a subnet connection of a terminal device.

[0361] Alternatively, if the second request message includes the first tunnel information, the third network element may send the first tunnel information to the second network element. The second user-plane network element may allocate the second tunnel information to the terminal device's subnet connection based on the first tunnel information. That is, the second user-plane network element may determine, based on the received first tunnel information, that a subnet connection needs to be established for the terminal device, and then allocate the second tunnel information to the terminal device's subnet connection. Optionally, the third network element simultaneously sends the first tunnel information and indication information #2 to the second network element.

[0362] Optionally, before the third network element sends indication information #2 and / or the first tunnel information to the second user plane network element, the third network element may select a second user plane network element from one or more user plane network elements in the second network to support the subnet connection of the terminal device, and forward the subnet service data between the terminal device and the subnet service node. For example, the third network element may select the second user plane network element based on one or more of the logical area to which the terminal device is allowed to access and the current location of the terminal device. For another example, the third network element is locally configured with a correspondence between the logical area and the user plane network elements in the second network. Based on the correspondence, the third network element selects the second user plane network element corresponding to the logical area to which the terminal device is allowed to access to support the subnet connection of the terminal device.

[0363] The QoS parameters of a terminal device are used to determine the quality of service parameters corresponding to the terminal device's subnet connection. For example, the third network element determines the QoS parameters of the terminal device based on the terminal device's subscription data and sends the QoS parameters of the terminal device to the second network element via a first response message. The QoS parameters of the terminal device may include QoS level, maximum bandwidth, preemption priority, etc.

[0364] It should be understood that when the first response message includes information for indicating the logical area to which the terminal device is allowed to access, the second tunnel information, and one or more of the first QoS parameters, the first response message may indicate acceptance of the connection establishment, that is, when the second network element receives the first response message, and the first response message includes information for indicating the logical area to which the terminal device is allowed to access, the second tunnel information, and one or more of the first QoS parameters, the second network element may determine that the third network element accepts the connection establishment.

[0365] Optionally, the communication method 200 further includes: the third network element sending one or more of the data packet filter, forwarding rule, and QoS rule corresponding to the subnet connection of the terminal device to the second user plane network element.

[0366] The packet filter is used to map subnet service data sent by the subnet service node to a QoS flow, so that the second user plane network element can send the subnet service data to the first user plane network element via the QoS flow. Forwarding rules may include rules for processing subnet service data sent by the subnet service node to the terminal device, such as adding a QoS flow identifier. QoS rules can be used to control the QoS of the terminal device's subnet connection, for example, controlling the maximum uplink and downlink bandwidth of the connection.

[0367] Exemplarily, the third network element can determine the data packet filter and forwarding rules based on the access permission information in the contract data of the terminal device. For example, when the access permission information indicates that the terminal device is not allowed to access the logical area #a, the data packet filter includes one or more addresses corresponding to the logical area #a, and the forwarding rule corresponding to the data packet filter indicates to discard the data packet, then when the second user-plane network element receives a subnet service data packet from the terminal device, the second user-plane network element determines that the destination address of the subnet service data packet belongs to the address corresponding to the logical area #a according to the data packet filter, then according to the instruction of the forwarding rule corresponding to the data packet filter, the subnet service data packet is discarded, thereby preventing the terminal device from accessing the logical area #a.

[0368] S260: The second network element sends a second response message to the first network element according to the first response message, where the second response message is used to indicate whether to accept the connection establishment. Correspondingly, the first network element receives the second response message from the second network element.

[0369] For example, in the case where the first response message is used to indicate the rejection of connection establishment, the second response message is used to indicate the rejection of connection establishment. It should be understood that the second response message can also be used to indicate the failure of connection establishment, to indicate the rejection of the access request of the terminal device, to indicate the failure of terminal device access, or to indicate the rejection of the subnet connection establishment of the terminal device. The embodiments of the present application do not impose any restrictions on this.

[0370] For example, when the first response message is used to indicate the acceptance of connection establishment, the second response message is used to indicate the acceptance of connection establishment. It should be understood that the second response message can also be used to indicate the successful establishment of the connection, to indicate the acceptance of the access request of the terminal device, to indicate the successful access of the terminal device, or to indicate the establishment of the subnet connection of the terminal device. The embodiments of the present application do not impose any restrictions on this.

[0371] Optionally, the second response message includes QoS parameters corresponding to the subnet connection of the terminal device, and the QoS parameters are determined based on at least one of the following: QoS parameters of the terminal device or QoS parameters of the second network.

[0372] For example, the subscription data of the second network includes the QoS parameters of the second network, and the second network element determines the QoS parameters corresponding to the subnet connection of the terminal device based on the QoS parameters of the second network.

[0373] For another example, the first response message includes the QoS parameters of the terminal device, and the subscription data of the second network includes the QoS parameters of the second network. When the QoS parameters of the terminal device and the QoS parameters of the second network meet the second condition, the QoS parameters corresponding to the subnet connection of the terminal device are the QoS parameters of the terminal device; or, when the QoS parameters of the terminal device and the QoS parameters of the second network do not meet the second condition, the QoS parameters corresponding to the subnet connection of the terminal device are the QoS parameters of the second network.

[0374] The second condition includes one or more of the following conditions:

[0375] (1) The QoS level in the QoS parameters of the terminal device is less than or equal to the QoS level in the QoS parameters of the second network;

[0376] (2) The maximum bandwidth in the QoS parameters of the terminal device is less than or equal to the maximum bandwidth in the QoS parameters of the second network.

[0377] For the sake of clarity and brevity, the QoS parameters of the terminal device in the first response message are referred to as first QoS parameters, and the QoS parameters of the second network in the subscription data of the second network are referred to as second QoS parameters. It should be understood that when the subscription data of the second network includes one or more groups of second QoS parameters, if the first QoS parameter and at least one group of second QoS parameters meet the second condition, the second network element can use the first QoS parameter as the QoS parameter corresponding to the subnet connection of the terminal device. If the first QoS parameter and all the second QoS parameters do not meet the second condition, the second network element can determine the QoS parameter corresponding to the subnet connection of the terminal device based on the first QoS parameter and the one or more groups of second QoS parameters. For example, if condition (2) in the second condition is not met, the second network element selects the group with the largest maximum bandwidth value from the multiple groups of second QoS parameters as the QoS parameter corresponding to the subnet connection of the terminal device.

[0378] Alternatively, when the first QoS parameter does not match any of the second QoS parameters, the second network element may also send a second response message indicating a connection establishment failure to the first network element.

[0379] It should be understood that when the second response message includes the quality of service parameters corresponding to the subnet connection of the terminal device, the second response message may indicate acceptance of the connection establishment. That is, when the first network element receives the quality of service parameters corresponding to the subnet connection of the terminal device, the first network element determines that the connection establishment of the terminal device is successful.

[0380] When the second response message indicates acceptance of the connection establishment, the second response message may also include one or more of wireless resource information, identification information of the second network element, a billing identifier, information indicating the logical area to which the terminal device is allowed to access, and second tunnel information.

[0381] Among them, the wireless resource information is used to indicate the wireless resources in the first network used to forward subnet service data between the terminal device and the second network, that is, the wireless resources are used by the first network to support the connection between the terminal device and the second network, that is, the wireless resources are used by the first network to forward subnet service data between the terminal device and the second network.

[0382] Exemplarily, the wireless resources include one or more data radio bearers (DRBs) for transmitting subnet service data on the air interface between the terminal device and the access network device of the first network (such as (R)AN 111 in Figure 1). For example, for the downlink subnet service data sent by the second network to the terminal device, after the access network device receives the subnet service data, it maps the subnet service data to the one or more DRBs and sends the subnet service data to the terminal device through the one or more DRBs. Correspondingly, for the uplink subnet service data sent by the terminal device to the second network, the terminal device maps the subnet service data to the one or more DRBs and sends the subnet service data to the access network device through the one or more DRBs.

[0383] The wireless resource message may be determined based on subscription data of the second network. For example, the wireless resource message may be determined based on wireless resource reservation information of the first network.

[0384] Exemplarily, the second network element determines the wireless resource reservation information of the first network from the subscription data of the second network based on the identification information of the first network, and then determines the wireless resource information based on the wireless resource reservation information. The second network element can determine whether the subnet connection of the terminal device uses the resources indicated by the wireless resource reservation information based on the first QoS parameter or the second QoS parameter. Exemplarily, when the QoS level in the first QoS parameter or the second QoS parameter is greater than a preset threshold, the second network element determines that the subnet connection of the terminal device can use all or part of the wireless resources indicated by the wireless resource reservation information, and then carries the wireless resource information corresponding to all or part of the wireless resources in the second response message. Among them, the preset threshold can be specified by the protocol or configured by the system, and the embodiments of the present application do not limit this.

[0385] The billing identifier is used to indicate billing for the wireless resources of the first network, where the wireless resources of the first network are used to forward service data for the second network, that is, for the second network to exchange service data with one or more terminal devices via the first network. For example, the billing identifier has two possible values: when the billing identifier takes the first value, billing is required; and when the billing identifier takes the second value, billing is not required.

[0386] Optionally, the second response message includes information for indicating the logical area to which the terminal device is allowed to access. For example, the second network element carries the second container in the first response message in the second response message and sends it to the first network element.

[0387] Optionally, the second response message includes the second tunnel information. For example, the second network element carries the second tunnel information in the first response message in the second response message and sends it to the first network element.

[0388] S270. The first network element sends a third request message to the access network device in the first network. Correspondingly, the access network device receives the third request message from the first network element.

[0389] For example, when the second response message indicates that the connection establishment is accepted, the first network element sends a third request message to the access network device. The first network element may send the third request message directly to the access network device, or may send the third request message indirectly to the access network device through other network elements. For example, the first network element may send the third request message to the access network device through the AMF network element.

[0390] The third request message is used to request allocation of wireless resources for the subnet connection of the terminal device, and the wireless resources are used to forward subnet service data between the terminal device and the second network.

[0391] Optionally, the third request message includes QoS parameters corresponding to the subnet connection of the terminal device. For example, the first network element carries the first QoS parameter or the second QoS parameter in the second response message in the third request message and sends it to the access network device.

[0392] Optionally, the third request message includes wireless resource information. For example, the first network element carries the wireless resource information in the second response message in the third request message and sends it to the access network device. In another example, the first network element maps the wireless resource information in the second response message to an internal identifier of the first network and sends the mapped internal identifier to the access network device.

[0393] Optionally, the third request message includes third tunnel information, and the third tunnel information is used for subnet service data transmission of the terminal device, that is, the third tunnel information is used to send uplink data of the subnet service to the first user plane network element, and the access network device can send the subnet service data of the terminal device to the first user plane network element according to the third tunnel information.

[0394] The third tunnel information may be allocated by the first user plane network element for the subnet connection of the terminal device. In this implementation, before the first network element sends the third request message to the access network device, the communication method 200 further includes:

[0395] S261. The first network element sends second tunnel information to the first user plane network element. Correspondingly, the first user plane network element receives the second tunnel information from the first network element.

[0396] S262. The first user plane network element sends the third tunnel information allocated by the first user plane network element to the subnet connection of the terminal device to the first network element. Correspondingly, the first network element receives the third tunnel information from the first user plane network element.

[0397] For example, after receiving the second tunnel information, the first user plane network element allocates third tunnel information to the subnet connection of the terminal device and sends the allocated third tunnel information to the first network element.

[0398] For another example, in step S261, the first network element further sends instruction information to the first user-plane network element, indicating that tunnel information is to be allocated for the terminal device's subnet connection. Alternatively, the instruction information is used to request that tunnel information be allocated for the terminal device's subnet connection. Correspondingly, the first user-plane network element receives the instruction information from the first network element, allocates third tunnel information for the terminal device's subnet connection based on the instruction information, and sends the allocated third tunnel information to the first network element.

[0399] Optionally, the third request message also includes a third response message sent to the terminal device. For example, the third response message is a non-access stratum (NAS) message. The access network device does not parse the third response message and directly transmits the third response message to the terminal device.

[0400] The third response message may be used to indicate acceptance of the access request of the terminal device, to indicate successful access of the terminal device to the second network, to indicate successful connection establishment, or to indicate acceptance of establishment of a subnet connection of the terminal device.

[0401] In the case where the third response message includes information for indicating the logical area that the terminal device is allowed to access, the third response message also includes the information for indicating the logical area that the terminal device is allowed to access. For example, the first network element obtains the second container from the second response message and includes the second container in the third response message.

[0402] Optionally, when the second response message is used to indicate rejection of connection establishment, the first network element sends a message indicating access failure to the terminal device. For example, the first network element may send a message indicating access failure to the terminal device via the access network device.

[0403] S280. The access network device sends a fourth response message to the first network element. Correspondingly, the first network element receives the fourth response message from the access network device. The fourth response message includes fourth tunnel information.

[0404] Among them, the fourth tunnel information is used for subnet service data transmission of the terminal device, that is, for sending downlink data of the subnet service to the access network device. The first user-side network element can send the subnet service data of the terminal device to the access network device according to the fourth tunnel information.

[0405] The fourth tunnel information may be tunnel information allocated by the access network device to the subnet connection of the terminal device. For example, the access network device allocates the fourth tunnel information to the subnet connection of the terminal device according to the third request message, or in other words, triggered by the third request message.

[0406] The access network device can send the fourth tunnel information directly to the first network element, or it can send the fourth tunnel information indirectly to the first network element through other network elements. For example, the access network device can send the fourth tunnel information to the first network element through the AMF network element.

[0407] The communication method 200 may further include: the access network device and the terminal device establishing wireless resources for a subnet connection of the terminal device.

[0408] For example, the access network device allocates wireless resources to the subnet connection of the terminal device according to the third request message. For example, when the third request message includes wireless resource information, the access network device may allocate wireless resources to the subnet connection of the terminal device according to the wireless resource information. For example, the access network device may allocate the wireless resources indicated by the wireless resource information to the subnet connection of the terminal device, and subsequently use the wireless resources to transmit the subnet service data of the terminal device. For another example, when the third request message includes the first QoS parameter or the second QoS parameter, the access network device may allocate wireless resources to the subnet connection of the terminal device according to the first QoS parameter or the second QoS parameter. The access network device may also allocate wireless resources to the subnet connection of the terminal device in combination with the first QoS parameter or the second QoS parameter and the wireless resource information.

[0409] In this implementation, the access network device can also establish the wireless resource with the terminal device. For example, the access network device and the terminal device can establish the wireless resource for the terminal device's subnet connection through radio resource control (RRC) connection reconfiguration. The specific process can be referred to the existing protocol and will not be repeated here.

[0410] The embodiment of the present application does not limit the order in which the access network device sends the fourth response message to the first network element and establishes the wireless resource between the access network device and the terminal device. For example, the access network device may send the fourth response message to the first network element after the wireless resource between the access network device and the terminal device is established. In this implementation, the fourth response message may also be used to indicate that the wireless resource between the access network device and the terminal device is established.

[0411] When the third request message includes a third response message, communication method 200 further includes: the access network device sending the third response message to the terminal device, and the terminal device correspondingly receiving the third response message from the access network device. The terminal device may confirm, based on the third response message, that it has successfully accessed the second network, i.e., that it has successfully established a connection with the second network, and may then exchange subnet service data with the second network.

[0412] Optionally, the access network device may send the third response message to the terminal device during the process of establishing wireless resources for subnet connection with the terminal device.

[0413] Through the above steps, the terminal device successfully accesses the second network, that is, the connection between the terminal device and the second network is successfully established. The following exemplifies the subnet service data transmission process between the terminal device and the second network.

[0414] When the uplink subnet service data reaches the terminal device, the terminal device sends the subnet service data to the access network device through the wireless resources established between the terminal device and the access network device. The access network device sends the subnet service data to the first user plane network element according to the third tunnel information. The first user plane network element then sends the subnet service data to the second user plane network element according to the second tunnel information. Finally, the second user plane network element sends the subnet service data to the subnet service node, thereby completing the transmission of the uplink subnet service data.

[0415] Similarly, after the second user plane network element receives the downlink subnet service data from the subnet service node, it sends the subnet service data to the first user plane network element according to the first tunnel information. The first user plane network element then sends the subnet service data to the access network device according to the fourth tunnel information. The access network device then sends the subnet service data to the terminal device through the wireless resources established between it and the terminal device, thereby completing the transmission of the downlink subnet service data.

[0416] According to the above-mentioned communication method 200 provided in the embodiment of the present application, the third network element in the second network determines whether to accept the establishment of a connection between the terminal device and the second network based on the subscription data of the terminal device, so that the second network can autonomously manage the establishment of a connection between the terminal device and the second network, reducing the complexity of deploying and maintaining the second network. In some implementations, the second network includes a fourth network element for managing the subscription data of the terminal device, that is, the subscription data of the terminal device can be stored in the second network instead of the first network, and the third network element can directly obtain the subscription data of the terminal device from the fourth network element, thereby realizing autonomous management of the subnet connection. Furthermore, the second network element can also control and manage the establishment of a connection between the terminal device and the second network, which can reduce unnecessary signaling overhead while reducing the processing complexity of the third network element and improving resource utilization.

[0417] In addition, in the existing subnets deployed based on technologies such as slicing, MEC, LADN, and standalone non-public network (SNPN), only terminal devices that have signed a contract with the subnet or terminal devices with a subscriber identity module (SIM) card of the subnet can access the subnet, which limits the application scenarios of the subnet. The network architecture 100 and communication method 200 provided in the embodiments of the present application can expand the scope of terminal devices that access the second network. For example, in some implementations, terminal devices that have not signed a contract with the second network can also access the second network. In other implementations, the contract data of the second network includes the identification information of the service operator of the terminal device, and the terminal device can access the second network. This can expand the application scenarios of the subnet and promote the development and promotion of the subnet.

[0418] Figure 4 is a flow chart of another communication method 400 provided in an embodiment of the present application. The communication method 400 can be regarded as a specific implementation of the communication method 200 shown in Figure 2. The communication method 400 takes the terminal device as the terminal device 140 in Figure 1, the access network device as the (R)AN 111, the first network as the operator network 110, the first network element as the G-SM network element 112, the second network element as the SNA network element 131, the second network as the subnet domain 120, and the third network element as the subnet SM network element 123 as an example to illustrate the specific implementation of the communication method 200. It should be understood that the communication method 400 and the communication method 200 may have the same or similar technical means. The relevant description in the above-mentioned communication method 200 is also applicable to the communication method 400. The content described in the communication method 200 will not be repeated in the communication method 400.

[0419] As shown in FIG4 , the communication method 400 includes the following steps.

[0420] S401 . The terminal device 140 sends a connection establishment request message to the G-SM network element 112 . Correspondingly, the G-SM network element 112 receives the connection establishment request message from the terminal device 140 .

[0421] The connection establishment request message is used to request the establishment of a connection between the terminal device 140 and the sub-network domain 120, that is, the connection establishment request message is used to request access to the sub-network domain 120. Hereinafter, the connection between the terminal device 140 and the sub-network domain 120 is referred to as the sub-network connection of the terminal device 140.

[0422] For example, when the terminal device 140 needs to use the subnet service provided by the subnet domain 120, the terminal device 140 sends a connection establishment request message to the G-SM network element 112 to initiate the establishment of the subnet connection, so that the terminal device 140 can interact with the subnet domain 120 through the subnet connection to exchange data related to the subnet service.

[0423] The connection establishment request message includes the identification information of the terminal device 140 and the identification information of the subnet domain 120, so that the G-SM network element 112 can know through the connection establishment request message that the terminal device initiating the connection establishment is the terminal device 140, and the target network that the terminal device 140 requests to access is the subnet domain 120.

[0424] Optionally, the connection establishment request message includes information indicating a target logical area of ​​the terminal device, such as identifiers of one or more logical areas to which the terminal device requests access. The terminal device may send the information indicating the target logical area of ​​the terminal device to the G-SM network element 112 via a container, thereby improving security.

[0425] S402 . The G-SM network element 112 sends a request message # 1 to the SNA network element 131 . Correspondingly, the SNA network element 131 receives the request message # 1 from the G-SM network element 112 .

[0426] For example, request message #1 may be the first request message in the communication method 200 .

[0427] Optionally, before G-SM network element 112 sends request message #1 to SNA network element 131, G-SM network element 112 obtains address information of SNA network element 131, such as the IP address of SNA network element 131. In this way, G-SM network element 112 can send request message #1 to SNA network element 131 based on the address information of SNA network element 131. For example, G-SM network element 112 receives the address information of SNA network element 131 from a DNS or an NRF network element in operator network 110. For specific implementations, refer to Method 2.1 and Method 2.2, and are not further described here.

[0428] Optionally, before G-SM network element 112 sends request message #1 to SNA network element 131, G-SM network element 112 receives, from G-UP network element 113, first tunnel information allocated by G-UP network element 113 for data transmission of the terminal device, and sends the first tunnel information to SNA network element 131 in request message #1. For the specific process of G-SM network element 112 receiving the first tunnel information from G-UP network element 113, refer to steps S221 and S222.

[0429] S403 : The SNA network element 131 determines whether the terminal device 140 is allowed to access the sub-network domain 120 .

[0430] For example, SNA network element 131 determines whether to allow terminal device 140 to access subnet domain 120 based on whether condition #1 is satisfied. The specific implementation of SNA network element 131 determining whether condition #1 is satisfied can be referred to step S230 and will not be repeated here.

[0431] When condition #1 is not satisfied, the SNA network element 131 determines that the terminal device 140 is not allowed to access the sub-network domain 120 , and the communication method 400 further includes the following steps S404 and S405 .

[0432] S404 . The SNA network element 131 sends a response message # 1 to the G-SM network element 112 . Correspondingly, the first network element receives the response message # 1 from the second network element.

[0433] S405 . In response to the response message # 1 , the G-SM network element 112 sends a connection establishment response message to the terminal device 140 . Correspondingly, the terminal device 140 receives the connection establishment response message from the G-SM network element 112 .

[0434] Response message #1 and the connection establishment response message are used to indicate that terminal device 140 is denied access to sub-network domain 120. Optionally, response message #1 and the connection establishment response message include a cause value to indicate the reason for denying terminal device 140 access to sub-network domain 120. For a detailed description of response message #1 and the connection establishment response message, please refer to steps S233 and S234.

[0435] When condition #1 is satisfied, the SNA network element 131 determines to allow the terminal device 140 to access the sub-network domain 120 , and the communication method 400 further includes the following steps S406 to S412 .

[0436] S406 . The SNA network element 131 sends a request message # 2 to the subnet SM network element 123 . Correspondingly, the subnet SM network element 123 receives the request message # 2 from the SNA network element 131 .

[0437] Optionally, before SNA network element 131 sends request message #2 to subnet SM network element 123, SNA network element 131 obtains the address information of subnet SM network element 123. For example, SNA network element 131 can obtain the address information of subnet SM network element 123 through any of methods 3.4-3.7.

[0438] Request message #2 may include identification information of the terminal device 140, location information of the terminal device 140, identification information of the operator network 110, information for indicating the target logical area of ​​the terminal device, and one or more of the first tunnel information. For a specific description, please refer to step S230 and will not be repeated here.

[0439] S407 . The subnet SM network element 123 determines whether the terminal device 140 is allowed to access the subnet domain 120 , and sends a response message # 2 to the SNA network element 131 .

[0440] For example, the subnet SM network element 123 determines whether to allow the terminal device 140 to access the subnet domain 120 based on whether condition #2 is met. If condition #2 is met, the subnet SM network element 123 determines that the terminal device 140 is allowed to access the subnet domain 120, and sends a response message #2 to the SNA network element 131. The response message #2 is used to indicate that the subnet connection establishment of the terminal device is accepted. If condition #2 is not met, the subnet SM network element 123 determines that the terminal device 140 is not allowed to access the subnet domain 120, and sends a response message #2 to the SNA network element 131. The response message #2 is used to indicate that the subnet connection establishment of the terminal device is rejected. The specific implementation method of the subnet SM network element 123 determining whether condition #2 is met can be referred to step S240. The response message #2 can be the first response message in the communication method 200.

[0441] When the subnet SM network element 123 determines that the terminal device 140 is allowed to access the subnet domain 120, the response message #2 may also include information for indicating the logical area to which the terminal device is allowed to access, second tunnel information, and one or more of the first QoS parameters. The specific implementation method can refer to step S240.

[0442] S408 . The SNA network element 131 sends a response message # 3 to the G-SM network element 112 according to the response message # 2 . Correspondingly, the G-SM network element 112 receives the response message # 3 from the SNA network element 131 .

[0443] The response message #3 may be the second response message in the communication method 200. The specific implementation of the SNA network element 131 sending the response message #3 to the G-SM network element 112 according to the response message #2 may refer to step S250.

[0444] In the case where the response message #3 is used to indicate that the terminal device 140 is denied access to the sub-network domain 120, the communication method 400 further includes the following step S409.

[0445] S409 : The G-SM network element 112 sends a connection establishment response message to the terminal device 140 , where the connection establishment response message is used to indicate that the terminal device 140 is denied access to the sub-network domain 120 . Correspondingly, the terminal device 140 receives the connection establishment response message from the G-SM network element 112 .

[0446] For example, the G-SM network element 112 may send a connection establishment response message to the terminal device 140 through the (R)AN 111 .

[0447] In the case where the response message #3 is used to indicate that the terminal device 140 is allowed to access the sub-network domain 120, the communication method 400 further includes the following steps S410-S412.

[0448] S410 , G-SM network element 112 sends request message #3 to (R)AN 111 , requesting (R)AN 111 to allocate radio resources for the subnet connection of terminal device 140 . Correspondingly, (R)AN 111 receives request message #3 from G-SM network element 112 .

[0449] S411 . (R)AN 111 sends fourth tunnel information to G-SM network element 112 .

[0450] S412 . (R)AN 111 and terminal device 140 establish wireless resources for subnet connection of terminal device 140 .

[0451] The specific implementation of the above steps S410-S412 can refer to steps S260-S270.

[0452] The beneficial effects of the communication method 400 can be referred to the communication method 200 and will not be described in detail here.

[0453] The above description, in conjunction with Figures 1 to 4 , details the communication method embodiment of the present application. The following description, in conjunction with Figures 5 to 7 , details the communication device embodiment of the present application. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment. Therefore, for portions not described in detail, reference can be made to the preceding method embodiment.

[0454] In the embodiment of the present application, the functional modules of the device can be divided according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. The following is an example of dividing each functional module according to each function.

[0455] Figure 5 is a schematic diagram of the structure of a communication device 1000 provided in an embodiment of the present application. As shown in Figure 5, the device 1000 may include a transceiver unit 1010 and a processing unit 1020. The transceiver unit 1010 can implement corresponding communication functions, and the processing unit 1020 is used to perform data processing, or in other words, the transceiver unit 1010 is used to perform operations related to receiving and sending, and the processing unit 1020 is used to perform other operations in addition to receiving and sending. The transceiver unit 1010 can also be referred to as a communication interface or a communication unit.

[0456] In one possible design, the communication device 1000 may correspond to the second network element in the above method embodiment, or a component of the second network element (such as a chip).

[0457] The communication device 1000 can implement the steps or processes corresponding to those executed by the second network element in the above method embodiment, wherein the transceiver unit 1010 can be used to perform operations related to transceiver transmission of the second network element in the above method embodiment, and the processing unit 1020 can be used to perform operations related to internal processing of the second network element in the above method embodiment.

[0458] Exemplarily, the transceiver unit 1010 is used to receive a first request message from a first network element in a first network, the first request message is used to request the establishment of a connection between a terminal device and a second network, the second network is used to provide services for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; the processing unit 1020 is used to send a second request message to a third network element in the second network through the transceiver unit 1010 according to the first request message, the second request message is used to request the establishment of the connection; the transceiver unit 1010 is also used to receive a first response message from the third network element, the first response message is used to indicate whether to accept the establishment of the connection; the processing unit 1020 is also used to send a second response message to the first network element through the transceiver unit 1010 according to the first response message, the second response message is used to indicate whether to accept the establishment of the connection.

[0459] When the device 1000 is used to execute the method in Figure 2, the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as steps S220, S230, S250, or S260; the processing unit 1020 can be used to execute the internal processing steps in the method.

[0460] In which, when the device 1000 is used to execute the method in Figure 4, the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as steps S402, S404, S406, S407, or S408; the processing unit 1020 can be used to execute the internal processing steps in the method, such as step S403.

[0461] It should be understood that the specific process of each unit executing the above steps can be found in the description of the above embodiment and will not be repeated here.

[0462] In another possible design, the communication device 1000 may correspond to the third network element in the above method embodiment, or a component (such as a chip) of the third network element.

[0463] The communication device 1000 can implement the steps or processes corresponding to those executed by the third network element in the above method embodiment, wherein the transceiver unit 1010 can be used to perform operations related to transceiver transmission of the third network element in the above method embodiment, and the processing unit 1020 can be used to perform operations related to internal processing of the third network element in the above method embodiment.

[0464] Exemplarily, the transceiver unit 1010 is used to receive a second request message from the second network element, the second request message is used to request the establishment of a connection between the terminal device and the second network, the second network is used to provide services for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; the processing unit 1020 is used to determine whether to accept the connection establishment based on the second request message and the contract data of the terminal device; the transceiver unit 1010 is also used to send a first response message to the second network element, the first response message is used to indicate whether to accept the connection establishment.

[0465] When the device 1000 is used to execute the method in FIG2 , the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as step S230 or S250; the processing unit 1020 can be used to execute the internal processing steps in the method, such as step S240.

[0466] When the device 1000 is used to execute the method in FIG4 , the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as step S406 or S407; the processing unit 1020 can be used to execute the internal processing steps in the method, such as step S407.

[0467] It should be understood that the specific process of each unit executing the above steps can be found in the description of the above embodiment and will not be repeated here.

[0468] In another possible design, the communication device 1000 may correspond to the first network element in the above method embodiment, or a component (such as a chip) of the first network element.

[0469] The communication device 1000 can implement the steps or processes corresponding to those executed by the first network element in the above method embodiment, wherein the transceiver unit 1010 can be used to perform operations related to the transmission and reception of the first network element in the above method embodiment, and the processing unit 1020 can be used to perform operations related to the internal processing of the first network element in the above method embodiment.

[0470] Exemplarily, the transceiver unit 1010 is used to receive a message from a terminal device for requesting the establishment of a connection between the terminal device and a second network, the second network being used to provide services for the terminal device, and the connection between the terminal device and the second network being used for the terminal device and the second network to transmit data of the service through the first network; the transceiver unit 1010 is also used to send a first request message to the second network element, the first request message being used to request the establishment of the connection; the transceiver unit 1010 is also used to receive a message from the second network element for indicating acceptance of the connection establishment; the transceiver unit 1010 is also used to send a third request message to the access network device in the first network, the third request message being used to request allocation of wireless resources for the connection, the wireless resources being used to forward data of the service between the terminal device and the second network.

[0471] In which, when the device 1000 is used to execute the method in Figure 2, the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as steps S210, S220, S260, S270, or S280; the processing unit 1020 can be used to execute the internal processing steps in the method.

[0472] In which, when the device 1000 is used to execute the method in Figure 4, the transceiver unit 1010 can be used to execute the steps of sending and receiving information in the method, such as steps S401, S402, S404, S405, S408, S409, S410, or S411; the processing unit 1020 can be used to execute the internal processing steps in the method.

[0473] It should be understood that the specific process of each unit executing the above steps can be found in the description of the above embodiment and will not be repeated here.

[0474] It should be understood that the device 1000 here is embodied in the form of a functional unit. The term "unit" here can refer to an application specific integrated circuit (ASIC), an electronic circuit, a processor (such as a shared processor, a dedicated processor or a group processor, etc.) and a memory for executing one or more software or firmware programs, a combined logic circuit and / or other suitable components that support the described functions. In an optional example, the above-mentioned transceiver unit 1010 can also be a transceiver circuit (for example, it can include a receiving circuit and a transmitting circuit), and the processing unit 1020 can be a processing circuit.

[0475] The apparatus 1000 of each of the above-mentioned solutions has the function of implementing the corresponding steps performed by the network elements (such as the second network element, the third network element, and the first network element) in the above-mentioned method. This function can be implemented by hardware, or it can be implemented by hardware executing the corresponding software. The hardware or software includes one or more modules corresponding to the above-mentioned functions; for example, the transceiver module can be replaced by a transceiver (for example, the transmitting unit in the transceiver module can be replaced by a transmitter, and the receiving unit in the transceiver module can be replaced by a receiver), and other units, such as the processing module, can be replaced by a processor to respectively perform the transceiver operations and related processing operations in each method embodiment.

[0476] Figure 6 is a schematic diagram of another communication device 2000 provided in an embodiment of the present application. The device 2000 includes one or more processors 2010 and one or more memories 2020. The processor 2010 is configured to execute computer programs or instructions stored in the memory 2020, or to read data / signaling stored in the memory 2020, to perform the methods described in the above method embodiments. The memory 2020 is configured to store computer programs or instructions and / or data. The memory 2020 may be integrated with the processor 2010, or may be provided separately.

[0477] 6 , the apparatus 2000 further includes a transceiver 2030 , which is configured to receive and / or transmit signals. For example, the processor 2010 is configured to control the transceiver 2030 to receive and / or transmit signals.

[0478] As a solution, the device 2000 is used to implement the operations performed by the second network element in each of the above method embodiments.

[0479] As another solution, the device 2000 is used to implement the operations performed by the third network element in the above method embodiments.

[0480] As another solution, the device 2000 is used to implement the operations performed by the first network element in the above method embodiments.

[0481] It should be understood that the processor mentioned in the embodiments of the present application may be a central processing unit (CPU), or may be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0482] It should also be understood that the memory mentioned in the embodiments of the present application may be a volatile memory and / or a non-volatile memory. 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). For example, RAM can be used as an external cache. By way of example and not limitation, RAM includes the following forms: static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

[0483] It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, the memory (storage module) can be integrated into the processor. It should also be noted that the memory described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0484] 7 is a schematic diagram of a chip system 3000 provided in an embodiment of the present application. The chip system 3000 (or also referred to as a processing system) includes a logic circuit 3010 and an input / output interface 1002 .

[0485] Logic circuit 3010 may be a processing circuit in chip system 3000. Logic circuit 3010 may be coupled to a storage unit and call instructions in the storage unit, so that chip system 3000 can implement the methods and functions of various embodiments of the present application. Input / output interface 3020 may be an input / output circuit in chip system 3000, outputting information processed by chip system 3000 or inputting data or signaling information to be processed into chip system 3000 for processing.

[0486] As a solution, the chip system 3000 is used to implement the operations performed by the second network element, the third network element, or the first network element in each of the above method embodiments. For example, the logic circuit 3010 is used to implement the internal processing-related operations performed by the second network element, the third network element, or the first network element in the above method embodiments; the input / output interface 3020 is used to implement the sending and / or receiving-related operations performed by the second network element, the third network element, or the first network element in the above method embodiments.

[0487] The explanation of the relevant contents and beneficial effects of any of the above-mentioned devices can be referred to the corresponding method embodiments provided above, which will not be repeated here.

[0488] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0489] An embodiment of the present application further provides a communication system, comprising a second network element and a third network element, wherein the second network element is configured to implement the operations performed by the second network element in each of the above method embodiments, and the third network element is configured to implement the operations performed by the third network element in each of the above method embodiments. Optionally, the communication system further comprises one or more network elements selected from a first network element, a fourth network element, or a fifth network element, wherein the first network element is configured to implement the operations performed by the first network element in each of the above method embodiments, the fourth network element is configured to implement the operations performed by the fourth network element in each of the above method embodiments, and the fifth network element is configured to implement the operations performed by the fifth network element in each of the above method embodiments.

[0490] The present application also provides a computer-readable storage medium storing computer instructions for implementing the methods performed by the second network element, the third network element, or the first network element in each of the above-described method embodiments. For example, when the computer program is executed by a computer, the computer can implement the methods performed by the second network element, the third network element, or the first network element in each of the above-described method embodiments.

[0491] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. For example, the computer can be a personal computer, a server, or a network device, etc. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)). For example, the available medium includes, but is not limited to, various media that can store program code, such as a USB flash drive, a mobile hard disk, ROM, RAM, a magnetic disk, or an optical disk.

[0492] In order to facilitate understanding of the embodiments of the present application, the following explanations are made.

[0493] First, in the various embodiments of the present application, unless otherwise specified or logically conflicting, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other. The technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.

[0494] Second, in the embodiments of this application, "plurality" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, and B exists alone, where A and B can be singular or plural. In the text description of this application, the character " / " generally indicates that the associated objects are in an "or" relationship.

[0495] Third, in the embodiments of the present application, "first," "second," and various numerical references (e.g., #1, #2, etc.) are used to distinguish between different messages for ease of description and are not intended to limit the scope of the embodiments of the present application. For example, they are used to distinguish between different messages, rather than to describe a specific order or precedence. It should be understood that the objects described in this manner can be interchanged where appropriate to describe scenarios other than the embodiments of the present application.

[0496] Fourth, in the embodiments of the present application, descriptions such as "when...", "in the case of...", and "if" all mean that the device will perform corresponding processing under certain objective circumstances. It does not limit the time, nor does it require the device to perform judgment actions when implemented, nor does it mean that there are other limitations.

[0497] Fifth, in the embodiments of the present application, 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 clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or apparatuses.

[0498] Sixth, in the embodiments of the present application, "used for indication" may include direct indication and indirect indication. When describing that a certain indication information is used to indicate A, it may include that the indication information directly indicates A or indirectly indicates A, and does not necessarily mean that the indication information carries A.

[0499] The indication methods involved in the embodiments of this application should be understood to encompass various methods that enable the party to be indicated to obtain information to be indicated. The information to be indicated can be sent as a whole or divided into multiple sub-information and sent separately. The transmission period and / or timing of these sub-information can be the same or different. This application does not limit the specific transmission method.

[0500] In the embodiments of the present application, the "indication information" may be an explicit indication, i.e., a direct indication via signaling, or may be obtained based on parameters indicated by the signaling, in combination with other rules, other parameters, or by deduction. It may also be an implicit indication, i.e., based on a rule or relationship, or based on other parameters, or by deduction. This application does not impose specific limitations on this.

[0501] Seventh, in the embodiments of the present application, "storage" may refer to storage in one or more memories. The one or more memories may be provided separately or integrated into an encoder or decoder, a processor, or a communication device. The one or more memories may also be partially provided separately and partially integrated into a decoder, a processor, or a communication device. The type of memory may be any form of storage medium and is not limited by this application.

[0502] Eighth, in the embodiments of the present application, "communication" can also be described as "data transmission", "information transmission", "data processing", etc. "Transmission" includes "sending" and "receiving", which is not limited in the present application.

[0503] The above description is merely a specific embodiment of the present application, but the scope of protection of the present 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: Applied to the second network element, including: receiving a first request message from a first network element in a first network, where the first request message is used to request establishment of a connection between a terminal device and a second network, where the second network is used to provide a service for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; Sending a second request message to a third network element in the second network according to the first request message, where the second request message is used to request establishment of the connection; receiving a first response message from the third network element, where the first response message is used to indicate whether to accept the connection establishment; A second response message is sent to the first network element according to the first response message, where the second response message is used to indicate whether to accept the connection establishment.

2. The method according to claim 1, characterized in that The first request message includes identification information of the terminal device, and the sending a second request message to a third network element in the second network according to the first request message includes: In a case where the user information of the second network includes the identification information of the terminal device, sending the second request message to the third network element; The user information of the second network includes identification information of one or more terminal devices that are allowed to establish a connection with the second network.

3. The method according to claim 2, characterized in that In a case where the user information of the second network includes identification information of the terminal device, the method further includes: Acquire subscription data of the second network.

4. The method according to any one of claims 1 to 3, characterized in that: The sending a second request message to a third network element in the second network according to the first request message includes: When the first request message and the subscription data of the second network meet a first condition, sending the second request message to the third network element, wherein the first condition includes one or more of the following conditions: (1) when the first request message includes identification information of the first network and the subscription data of the second network includes identification information of one or more networks, the identification information of the one or more networks includes the identification information of the first network; (2) When the first request message includes information indicating the location of the terminal device and the subscription data of the second network includes a service range of the second network, the service range of the second network includes the location of the terminal device.

5. The method according to any one of claims 1 to 4, characterized in that: Before sending the second request message to the third network element in the second network according to the first request message, the method further includes: Acquire the number of terminal devices that have accessed the second network; It is determined that the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network.

6. The method according to claim 5, characterized in that In a case where the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network, the method further includes: A message for requesting to update the number of terminal devices that have accessed the second network is sent to a fourth network element, and the fourth network element is used to maintain the number of terminal devices that have accessed the second network.

7. The method according to claim 6, characterized in that Before sending the second request message to the third network element in the second network according to the first request message, the method further includes: It is determined that the number of terminal devices that have accessed the second network is updated successfully.

8. The method according to any one of claims 1 to 7, characterized in that: The second response message includes a quality of service parameter of the connection, where the quality of service parameter of the connection is determined according to at least one of the following: a quality of service parameter of the terminal device or a quality of service parameter of the second network.

9. The method according to claim 8, characterized in that The first response message includes the quality of service parameter of the terminal device, and the subscription data of the second network includes the quality of service parameter of the second network; In the case where the quality of service parameter of the terminal device and the quality of service parameter of the second network meet the second condition, the quality of service parameter of the connection is the quality of service parameter of the terminal device; or, In the case where the quality of service parameter of the terminal device and the quality of service parameter of the second network do not satisfy the second condition, the quality of service parameter of the connection is the quality of service parameter of the second network; The second condition includes one or more of the following conditions: The quality of service level in the quality of service parameters of the terminal device is less than or equal to the quality of service level in the quality of service parameters of the second network; The maximum bandwidth in the quality of service parameters of the terminal device is less than or equal to the maximum bandwidth in the quality of service parameters of the second network.

10. The method according to any one of claims 1 to 9, characterized in that: The second response message includes a charging identifier, where the charging identifier is used to indicate charging for wireless resources of the first network, and the wireless resources of the first network are used to forward service data for the second network.

11. A communication method, characterized in that: A third network element applied to the second network includes: receiving a second request message from a second network element, where the second request message is used to request establishment of a connection between a terminal device and the second network, where the second network is used to provide a service for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; Determining whether to accept the connection establishment according to the second request message and the subscription data of the terminal device; A first response message is sent to the second network element, where the first response message is used to indicate whether to accept the connection establishment.

12. The method according to claim 11, characterized in that The contract data of the terminal device is contract data created when the terminal device and the second network sign a contract, or the contract data of the terminal device is default contract data.

13. The method according to claim 11 or 12, characterized in that: The determining whether to accept the connection establishment according to the second request message and the subscription data of the terminal device includes: If the second request message and the subscription data of the terminal device meet a third condition, determining to accept the connection establishment; or, If the second request message and the subscription data of the terminal device do not satisfy a third condition, determining not to accept the connection establishment; The third condition includes one or more of the following conditions: 1) when the second request message includes information indicating the location of the terminal device, and the subscription data of the terminal device includes information indicating one or more geographical areas that the terminal device is allowed to access, the one or more geographical areas that the terminal device is allowed to access include the location of the terminal device; 2) When the second request message includes information indicating the logical area that the terminal device requests to access, and the subscription data of the terminal device includes information indicating one or more logical areas that the terminal device is allowed to access, the one or more logical areas that the terminal device is allowed to access include the logical area that the terminal device requests to access.

14. The method according to any one of claims 11 to 13, characterized in that: The first response message is used to indicate acceptance of the connection establishment, and before sending the first response message to the second network element, the method further includes: It is determined that authentication of the terminal device is not required.

15. The method according to claim 14, characterized in that The determining that authentication of the terminal device is not required includes: When one or more of the following conditions are met, it is determined that the terminal device does not need to be authenticated: The contract data of the terminal device includes information for indicating that the terminal device does not need to be authenticated; The second request message includes identification information allocated by the first network to the terminal device, and the identification information is credible.

16. The method according to any one of claims 11 to 15, characterized in that: The first response message is used to indicate acceptance of the connection establishment, and before sending the first response message to the second network element, the method further includes: The terminal device is successfully authenticated.

17. The method according to claim 16, characterized in that The contract data of the terminal device includes authentication information of the terminal device, and the successful authentication of the terminal device includes: The terminal device is successfully authenticated using the authentication information.

18. The method according to any one of claims 11 to 17, characterized in that: The first response message includes a quality of service parameter of the terminal device, and the quality of service parameter of the terminal device is used to determine a quality of service parameter of the connection.

19. The method according to any one of claims 11 to 18, characterized in that: Before determining whether to accept the connection establishment according to the second request message and the subscription data of the terminal device, the method further includes: Sending a message for requesting the subscription data of the terminal device to a fifth network element in the second network, the fifth network element being used to manage the subscription data of the terminal device subscribed to the second network; Receive the subscription data from the fifth network element.

20. A communication method, characterized in that: Applied to a first network element in a first network, the method comprises: receiving a message from a terminal device for requesting establishment of a connection between the terminal device and a second network, the second network being used to provide a service for the terminal device, the connection between the terminal device and the second network being used for the terminal device and the second network to transmit data of the service through the first network; Sending a first request message to the second network element, where the first request message is used to request establishment of the connection; receiving a message from the second network element indicating acceptance of the connection establishment; A third request message is sent to an access network device in the first network, where the third request message is used to request allocation of wireless resources for the connection, where the wireless resources are used to forward data of the service between the terminal device and the second network.

21. The method according to claim 20, characterized in that Before sending the first request message to the second network element, the method further includes: Obtaining address information of the second network element; The sending a first request message to the second network element includes: Send the first request message to the second network element according to the address information of the second network element.

22. The method according to claim 20 or 21, characterized in that The third request message includes a quality of service parameter corresponding to the connection, and the quality of service parameter is determined according to a quality of service parameter of the terminal device and / or a quality of service parameter of the second network.

23. The method according to any one of claims 20 to 22, characterized in that: The third request message includes wireless resource information, and the wireless resource information is used to determine the wireless resource.

24. The method according to any one of claims 20 to 23, characterized in that: The first request message includes first tunnel information, and the first tunnel information is used to send downlink data of the service to a first user plane network element in the first network.

25. The method according to claim 24, characterized in that Before sending the first request message to the second network element, the method further includes: Sending, to the first user plane network element, indication information for instructing the first user plane network element to allocate downlink tunnel information for the connection; Receive the first tunnel information from the first user plane network element.

26. The method according to any one of claims 20 to 25, characterized in that: The third request message includes third tunnel information, and the third tunnel information is used to send uplink data of the service to the first user plane network element in the first network.

27. The method according to claim 26, characterized in that Before sending the third request message to the access network device in the first network, the method further includes: Sending, to the first user plane network element, indication information for instructing the first user plane network element to allocate uplink tunnel information for the connection; Receive the third tunnel information from the first user plane network element.

28. The method according to any one of claims 20 to 27, characterized in that: The method further includes: Receive fourth tunnel information from the access network device, where the fourth tunnel information is used to send downlink data of the service to the access network device.

29. The method according to claim 28, characterized in that The third request message includes instruction information for instructing the access network device to allocate tunnel information for the connection; The receiving fourth tunnel information from the access network device includes: A message for responding to the third request message is received from the access network device, where the message includes the fourth tunnel information.

30. A communication device, characterized in that: include: One or more functional units, wherein the one or more functional units are used to execute the method as described in any one of claims 1-10, or the one or more functional units are used to execute the method as described in any one of claims 11-19, or the one or more functional units are used to execute the method as described in any one of claims 20-29.

31. A communication device, characterized in that: include: a processor coupled to the memory; The processor is used to execute the computer program stored in the memory so that the device performs the method according to any one of claims 1 to 10, or the device performs the method according to any one of claims 11 to 19, or the device performs the method according to any one of claims 20 to 29.

32. A computer-readable storage medium, characterized in that: include: The computer-readable storage medium stores a computer program, and when the computer program runs on a computer, the computer executes the method according to any one of claims 1 to 10, or the computer executes the method according to any one of claims 11 to 19, or the computer executes the method according to any one of claims 20 to 29.

33. A communication system, characterized in that: The method comprises a second network element and a third network element, wherein the second network element is used to execute the method according to any one of claims 1 to 10, and the third network element is used to execute the method according to any one of claims 11 to 19.

34. The system according to claim 33, characterized in that The system also includes a first network element, wherein the first network element is used to execute the method according to any one of claims 20-29.

35. A communication method, characterized in that: include: The second network element receives a first request message from a first network element in the first network, where the first request message is used to request establishment of a connection between a terminal device and a second network, where the second network is used to provide a service for the terminal device, and the connection between the terminal device and the second network is used for the terminal device and the second network to transmit data of the service through the first network; The second network element sends a second request message to a third network element in the second network according to the first request message, where the second request message is used to request establishment of the connection; The third network element receives the second request message from the second network element, and determines whether to accept the connection establishment according to the second request message and the subscription data of the terminal device; The third network element sends a first response message to the second network element, where the first response message is used to indicate whether to accept the connection establishment; The second network element receives the first response message from the third network element, and sends a second response message to the first network element according to the first response message, where the second response message is used to indicate whether to accept the connection establishment.

36. The method according to claim 35, characterized in that The first request message includes identification information of the terminal device, and the second network element sends a second request message to a third network element in the second network according to the first request message, including: In a case where the user information of the second network includes identification information of the terminal device, the second network element sends the second request message to the third network element; The user information of the second network includes identification information of one or more terminal devices that are allowed to establish a connection with the second network.

37. The method according to claim 35 or 36, characterized in that The second network element sending a second request message to a third network element in the second network according to the first request message includes: When the first request message and the subscription data of the second network meet a first condition, the second network element sends the second request message to the third network element, wherein the first condition includes one or more of the following conditions: (1) when the first request message includes identification information of the first network and the subscription data of the second network includes identification information of one or more networks, the identification information of the one or more networks includes the identification information of the first network; (2) When the first request message includes information indicating the location of the terminal device and the subscription data of the second network includes a service range of the second network, the service range of the second network includes the location of the terminal device.

38. The method according to any one of claims 35 to 37, characterized in that Before the second network element sends a second request message to a third network element in the second network according to the first request message, the method further includes: The second network element obtains the number of terminal devices that have accessed the second network; The second network element determines that the number of terminal devices that have accessed the second network is less than the maximum number of terminal devices allowed to simultaneously access the second network.

39. The method according to any one of claims 35 to 38, characterized in that: The second response message includes a quality of service parameter of the connection, where the quality of service parameter of the connection is determined according to at least one of the following: a quality of service parameter of the terminal device and a quality of service parameter of the second network.

40. The method according to any one of claims 35 to 39, characterized in that: The third network element determines whether to accept the connection establishment according to the second request message and the subscription data of the terminal device, including: In a case where the second request message and the subscription data of the terminal device meet a third condition, the third network element determines to accept the connection establishment; or, If the second request message and the subscription data of the terminal device do not satisfy a third condition, the third network element determines not to accept the connection establishment; The third condition includes one or more of the following conditions: 1) when the second request message includes information indicating the location of the terminal device, and the subscription data of the terminal device includes information indicating one or more geographical areas that the terminal device is allowed to access, the one or more geographical areas that the terminal device is allowed to access include the location of the terminal device; 2) When the second request message includes information indicating the logical area that the terminal device requests to access, and the subscription data of the terminal device includes information indicating one or more logical areas that the terminal device is allowed to access, the one or more logical areas that the terminal device is allowed to access include the logical area that the terminal device requests to access.

41. The method according to any one of claims 35 to 40, characterized in that The first response message is used to indicate acceptance of the connection establishment, and before the third network element sends the first response message to the second network element, the method further includes: The third network element determines that it is not necessary to authenticate the terminal device, or the third network element successfully authenticates the terminal device.

42. The method according to any one of claims 35 to 41, characterized in that The method further comprises: The first network element receives a message from the terminal device for requesting establishment of a connection between the terminal device and the second network; The first network element sends the first request message to the second network element; The first network element receives the second response message from the second network element; When the second response message indicates acceptance of the connection establishment, the first network element sends a third request message to the access network device in the first network, and the third request message is used to request allocation of wireless resources for the connection, and the wireless resources are used to forward data of the service between the terminal device and the second network.

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