JP7755071B2 - Communication method and apparatus - Google Patents

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Chinese Patent Application No. 202111481414.7, entitled "Communication Method and Apparatus," filed with the State Intellectual Property Office of the People's Republic of China on December 6, 2021, which is incorporated herein by reference in its entirety.

This application relates to the field of communications technology, and more particularly to communications methods and devices.

Currently, the 3rd Generation Partnership Project (3GPP) (registered trademark, hereinafter the same) protocols support interworking between fourth-generation (4G) mobile communication technology networks (i.e., 4G networks) and fifth-generation (5G) mobile communication technology networks (i.e., 5G networks).

When a terminal device supports both 4G and 5G networks, the serving network of the terminal device may be handed over between the 4G and 5G networks. For example, when the terminal device is in a connected state, the serving cell of the terminal device may be handed over from a cell of the 4G network to a cell of the 5G network, or from a cell of the 5G network to a cell of the 4G network. When the terminal device is in an idle state, the camping cell of the terminal device may be reselected from a cell of the 4G network to a cell of the 5G network, or from a cell of the 5G network to a cell of the 4G network.

However, as the serving network of a terminal device is handed over between a 4G network and a 5G network, a series of signaling interaction procedures must be performed between network devices. As a result, when the serving network of a terminal device is handed over frequently between a 4G network and a 5G network, transmission resource overhead increases and performance consumption of the network device increases.

This application provides a communication method and apparatus for suppressing frequent handovers of a terminal device's serving network between a first network and a second network, thereby reducing transmission resource overhead and performance consumption of the network device.

According to a first aspect, one embodiment of the present application provides a communication method. The method can be applied to a first communication device. In the method, the first communication device receives a first request message from a second communication device during a first period, the first request message belonging to a first type of request message, and when the number of the first type of request messages received during the first period is greater than a first threshold, transmits first indication information to the second communication device, the first indication information indicating a rejection of the request of the first request message. The first type of request message is used to request a handover of a serving network of a terminal device from a first network to a second network, and the first network and the second network are networks supporting different communication standards.

According to this method, statistics on the number of first-type request messages within a first period are collected. When the number of first-type request messages is greater than a first threshold, the request for the first request message may be rejected, i.e., the subsequent procedure corresponding to "handing over the serving network of the first terminal device from the first network to the second network" is not performed, effectively preventing the serving network of the first terminal device from being frequently handed over between the first network and the second network. This reduces transmission resource overhead and reduces performance consumption of the network device.

In a possible design, the step of handing over the serving network of the terminal device from the first network to the second network includes a step of handing over the serving cell of the terminal device from a cell of the first network to a cell of the second network, or a step of reselecting the camping cell of the terminal device from a cell of the first network to a cell of the second network.

In a possible design, the first type request message includes first information, which indicates that the terminal device is located within a first area; the first type request message includes second information, which indicates that the type of the terminal device is a first terminal type; or the first type request message includes the first information and the second information.

In other words, the first type of request message may correspond to a specific terminal device, the first type of request message may correspond to a specific terminal device located within a first area, the first type of request message may correspond to a terminal device of a first terminal type, the first type of request message may correspond to a terminal device located within the first area, or the first type of request message may correspond to a terminal device of a first terminal type located within the first area. In this way, objects corresponding to the first type of request message can be flexibly configured. For example, the first type of request message may correspond to a specific terminal device, or to a specific terminal device within a specific area. This allows for more precise control and can meet the requirements of multiple scenarios.

In a possible design, after receiving a first request message from the second communication device during the first period, the method further includes receiving a second request message from the second communication device during the first period, the second request message belonging to a first type of request message, and discarding the second request message and sending second instruction information to the second communication device or third instruction information to the third communication device. The second instruction information indicates that the request for the second request message is prohibited, and the third instruction information indicates that the terminal device is to be deregistered from the first network.

In this way, the second instruction information is transmitted to the second communication device, or the third instruction information is transmitted to the third communication device, to avoid receiving the first type of request message during the second period and reduce transmission resource overhead.

In a possible design, the second request message is received during a second period included in the first period, and the start of the second period is the time when the first instruction information is transmitted.

In a possible design, the second request message is the first request message of the first type received by the first communication device during the second period.

In a possible design, the method further includes a step of sending fourth instruction information to the second communication device at the end of the second period, the fourth instruction information indicating that the request of the second request message is permitted.

In a possible design, the first network is a 4G network and the second network is a 5G network, or the second network is a 4G network and the first network is a 5G network.

According to a second aspect, the present application provides a communication device. The communication device may be a first communication device. The communication device has functionality for implementing the first aspect. For example, the communication device includes a corresponding module, unit, or means for performing the operations of the first aspect. The module, unit, or means may be implemented by software or hardware, or by hardware executing corresponding software.

In one possible design, the communication device includes a processing unit and a communication unit. The communication unit may be configured to transmit and receive signals to implement communication between the communication device and another device. The processing unit may be configured to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit may correspond to operations in a first aspect. For example, in one embodiment, the communication unit is configured to: receive a first request message from a second communication device during a first period, the first request message belonging to a first type of request message; and, when the processing unit determines that the number of first type request messages received during the first period is greater than a first threshold, send first indication information to the second communication device, the first indication information indicating a rejection of the request for the first request message. The first type of request message is used to request a handover of a serving network of a terminal device from a first network to a second network, where the first network and the second network are networks supporting different communication standards.

In a possible design, the communications device may include a processor, and the processor may be configured to be coupled to a memory. The memory may store computer programs or instructions necessary to implement the functionality of the first aspect. The processor may execute the computer programs or instructions stored in the memory. When the computer programs or instructions are executed, the communications device is enabled to perform the method of any one of the possible designs or implementations of the first aspect.

In a possible design, the communications device includes a processor and a memory. The memory can store computer programs or instructions necessary to implement the functionality of the first aspect. The processor can execute the computer programs or instructions stored in the memory. When the computer programs or instructions are executed, the communications device is enabled to perform the method of any one of the possible designs or implementations of the first aspect.

In a possible design, the communications device includes a processor and an interface circuit, the processor configured to communicate with another device through the interface circuit and to perform the method in any one of the possible designs or implementations of the first aspect.

In the second aspect, it will be understood that the processor may be implemented using hardware or software. When the processor is implemented using hardware, the processor may be a logic circuit, an integrated circuit, etc., or when the processor is implemented using software, the processor may be a general-purpose processor and is implemented by reading software code stored in a memory. In addition, there may be one or more processors and one or more memories. The memory may be integrated with the processor, or the memory and processor may be located separately. In a particular implementation process, the memory and processor may be integrated into one chip or located on different chips. The type of memory and the manner in which the memory and processor are located are not limited to the embodiments of the present application.

According to a third aspect, the present application provides a computer-readable storage medium. The computer storage medium stores computer-readable instructions. When the computer-readable instructions are read and executed on a computer, the computer is enabled to perform a method in any one of the possible designs of the first aspect.

According to a fourth aspect, the present application provides a computer program product. When the computer program product is read and executed on a computer, the computer is enabled to perform the method in any one of the possible designs of the first aspect.

According to a fifth aspect, the present application provides a chip. The chip includes a processor. The processor is coupled to a memory and configured to read and execute a software program stored in the memory to perform a method according to any one of the possible designs of the first aspect.

These and other aspects of the present application will become more apparent from the description of the embodiments below.

1 is a schematic diagram of a network architecture to which an embodiment of the present application is applicable; FIG. 2 illustrates an example of signaling interaction between a third-party network element and a core network element according to an embodiment of the present application. FIG. 2 illustrates an example of signaling interaction between a third-party network element and a core network element according to an embodiment of the present application. 1 is a schematic flowchart corresponding to a communication method according to an embodiment of the present application; 2 is a schematic diagram of a manner in which a first communication device processes a first type request message according to an embodiment of the present application; 2 is a schematic diagram of a manner in which a first communication device processes a first type request message according to an embodiment of the present application; 2 is a schematic diagram of a manner in which a first communication device processes a first type request message according to an embodiment of the present application; 2 is a schematic diagram of a manner in which a first communication device processes a first type request message according to an embodiment of the present application; 2 is a schematic diagram of a manner in which a first communication device processes a first type request message according to an embodiment of the present application; 1 is a schematic diagram of a first period including multiple second periods according to an embodiment of the present application; FIG. 1 is a schematic diagram of a first type request message corresponding to multiple terminal devices according to an embodiment of the present application; 1 is a block diagram of a possible example of an apparatus according to an embodiment of the present application; 1 is a block diagram of a possible structure of an apparatus according to an embodiment of the present application;

To clarify the objectives, technical solutions, and advantages of the embodiments of the present application, the following further describes the embodiments of the present application in detail with reference to the accompanying drawings. The technical solutions of the embodiments of the present application may be used in various communication systems, such as a global system for mobile communication (GSM), a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a general packet radio service (GPRS) system, the fourth generation (4G) communication system, or the fifth generation (5G) communication system, or in future communication systems or other similar communication systems. A 4G communication system may also be referred to as a long term evolution (LTE) system. An LTE system may include an LTE frequency division duplex (FDD) system and an LTE time division duplex (TDD) system. A 5G communication system may also be referred to as a new radio (NR) system.

The network architectures and service scenarios described in this application are intended to more clearly explain the technical solutions in this application and do not constitute limitations on the technical solutions provided in this application. Those skilled in the art will understand that with the evolution of network architectures and the emergence of new service scenarios, the technical solutions provided in this application will also be applicable to similar technical problems.

The following describes the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application.

FIG. 1A is a schematic diagram of a network architecture to which an embodiment of the present application can be applied. In this network architecture, a first network and a second network may be deployed together. As shown in FIG. 1A, the network architecture may include a terminal device, a network element included in the first network, and a network element included in the second network.

(1) Terminal Device A terminal device may also be referred to as user equipment (UE), terminal, mobile station (MS), mobile terminal (MT), customer premises equipment (CPE), residential gateway (RG), etc., and may be a device with wireless transceiver capabilities. A terminal device may be deployed on land, including indoors or outdoors and/or handheld or vehicle-mounted, on water (e.g., on a ship), or in the air (e.g., on an aircraft, balloon, or satellite). A terminal device may include a handheld device, a vehicle-mounted device, a wearable device, or a computing device with wireless communication capabilities. For example, a terminal device may be a mobile phone, a tablet computer, or a computer with wireless transceiver capabilities. Alternatively, the terminal device may be a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, an industrial control wireless terminal, an autonomous driving wireless terminal, a remote medical wireless terminal, a smart grid wireless terminal, a smart city wireless terminal, a smart home wireless terminal, etc.

(2) First Network and Second Network The first network and the second network may be networks supporting different communication standards. The first network may also be referred to as a network of the first communication standard, and the second network may also be referred to as a network of the second communication standard. For example, the first network may be a 4G network and the second network may be a 5G network, or the first network may be a 5G network and the second network may be a 4G network. The 5G network may also be referred to as a 5G communication system, and the 4G network may also be referred to as an evolved packet system (EPS) or a 4G communication system.

It will be understood that the first network and the second network may also be other types of networks. For example, the first network may be a GSM network and the second network may be a CDMA network, or the first network may be a CDMA network and the second network may be a GSM network. This is not particularly limited. In the embodiments of the present application, a 4G network and a 5G network are used as illustrative examples.

A 4G network may include the following network elements:

1. An access network (AN) element is configured to provide network access functions to authorized terminal devices within a specific area and can use transmission tunnels with different qualities based on the terminal device's level, service requirements, etc. The access network element can manage radio resources to transfer control signals and terminal device data between the terminal device and the core network and provide access services to the terminal device. An access network element may also be understood as a base station in a conventional network. In a 4G network, an access network element may also be called an evolved universal terrestrial radio access network (E-UTRAN) or evolved NodeB (eNB).

2. The mobility management network element is configured to provide mobility management functions. In addition, the MME may further provide functions such as lawful interception and access authorization/authentication. In 4G networks, the mobility management network element may be referred to as a mobility management entity (MME).

3. The serving gateway (SGW) is configured to provide user data forwarding and other functions.

4. The packet data network gateway user plane function (PGW-U) network element is configured to provide the user plane functions of the PDN gateway.

5. The packet data network gateway control plane function (PGW-C) network element is configured to provide the control plane functions of the PDN gateway.

6. A policy and charging rules function (PCRF) network element is configured to provide a unified policy framework to guide network behavior, provide policy rule information for control plane function network elements, etc.

7. The home subscriber server (HSS) contains user profiles, is configured to perform authentication and authorization of user identities, and can provide information regarding the user's physical location.

A 5G network may include the following network elements:

1. Access network elements are configured to provide network access functions to authorized terminal devices within a specific area and can use transmission tunnels with different qualities based on the terminal device's level, service requirements, etc. In 5G networks, access network elements may also be referred to as next generation radio access networks (NG-RANs) or next generation NodeBs (gNBs).

2. The mobility management network element is configured to perform access management and mobility management, and may further provide functions such as lawful interception and access authorization/authentication. In 5G networks, the mobility management network element may also be referred to as an access and mobility management function (AMF) network element.

3. User plane function (UPF) network elements are configured to perform packet routing and forwarding, quality of service (QoS) processing for user plane data, etc.

4. The session management function (SMF) network element is primarily configured to perform session management, Internet Protocol (IP) address allocation and management for terminal devices, and selection and management of user plane functions. In addition, the SMF may terminate the interface to policy control and charging functions.

5. The policy control function (PCF) network element is configured to provide a unified policy framework for managing network behavior, provide policy rule information for control plane function network elements (e.g., AMF or SMF), etc.

6. The unified data management (UDM) network element is configured to manage subscription data. In addition, the unified data management network element is further configured to perform user service registration management, terminal device identifier processing, access authentication, etc.

In the network architecture shown in FIG. 1A, since the 4G network and the 5G network are deployed together, network elements having the same or similar functions in the 4G network and the 5G network may be integrated. For example, the UPF and PGW-U may be integrated, and the integrated network element is referred to as a UPF+PGW-U network element. The SMF and PGW-C may be integrated, and the integrated network element is referred to as an SMF+PGW-C network element. The PCF and PCRF may be integrated, and the integrated network element is referred to as a PCF network element. The HSS and UDM may be integrated, and the integrated network element is referred to as an HSS+UDM network element.

In addition, although not shown in the figure, the network architecture may further include other possible network elements. It will be understood that the network elements in the first network and the second network may collectively be referred to as network devices.

Optionally, the network architecture shown in FIG. 1A may further include one or more third-party devices or network elements (not shown in FIG. 1A), such as a network data analytics function (NWDAF). The NWDAF network element may communicate with core network elements in the first network or the second network.

In the network architecture shown in FIG. 1A, it will be understood that letters and numbers near the connecting lines between network elements indicate the names of the communication interfaces between the entities. For the meaning of the communication interfaces, please refer to the meanings defined in the relevant standard protocols. The communication interfaces between the entities may alternatively have other names. This is not particularly limited.

A network element in an embodiment of the present application may also be referred to as a functional entity or an entity. For example, the AMF network element in FIG. 1A may also be referred to as an AMF entity. In addition, an AMF network element or an AMF entity may also be referred to as an AMF. A network element may be a network element in a hardware device, software running on dedicated hardware, or a virtualization function instantiated on a platform (e.g., a cloud platform). Optionally, a network element may be implemented by a single device (e.g., an AMF network element may also be referred to as an AMF device). This is not particularly limited in the embodiments of the present application.

The network architecture shown in FIG. 1A is a network architecture described from the perspective of a service-oriented architecture, and is not limited to this network architecture as applicable to the embodiments of the present application. Any network architecture capable of implementing the functionality of a network element is applicable to the embodiments of the present application.

In the network architecture shown in FIG. 1A, when a terminal device supports 4G and 5G networks, the serving network of the terminal device may be handed over between the 4G network and the 5G network. For example, when the terminal device is in a connected state, the serving cell of the terminal device may be handed over from a cell of the 4G network to a cell of the 5G network, or from a cell of the 5G network to a cell of the 4G network. When the terminal device is in an idle state, the camping cell of the terminal device may be reselected from a cell of the 4G network to a cell of the 5G network, or from a cell of the 5G network to a cell of the 4G network.

For several reasons, the serving network of a terminal device may be frequently handed over between a 4G network and a 5G network. For example, because the carrier frequency used by the 5G network is higher, the coverage capability of the 5G network is weaker than that of the 4G network. Typically, in the cell edge area of the 5G network, the signal of the 4G network is stronger and the signal of the 5G network is weaker. However, the threshold configured by the network device for reporting 5G neighbor cell measurement events is low. Therefore, when the terminal device is in the cell edge area of the 5G network, the network device tends to hand over the terminal device to a cell of the 5G network. Furthermore, after the terminal device is handed over to the cell of the 5G network, the signal of the 5G network is weak, so the network device may hand over the terminal device again to a cell of the 4G network device. As a result, the terminal device is frequently handed over between the cell of the 4G network and the cell of the 5G network.

In another example, the power consumption required by a terminal device to use a 5G network is greater than the power consumption required by a terminal device to use a 4G network. Therefore, when the display of the terminal device is in a screen-on state, the terminal device can enable 5G capabilities, for example, the terminal device can perform a cell search process for the 5G network, and when the display of the terminal device is in a screen-off state, the terminal device can disable 5G capabilities and return to the 4G network to reduce the power consumption of the terminal device. However, because a user may frequently turn the screen on and off when using the terminal device, the terminal device will frequently reselect between cells of the 4G network and cells of the 5G network.

However, as the serving network of a terminal device is handed over between a 4G network and a 5G network, a series of signaling interaction procedures must be performed between network devices. As a result, when the serving network of a terminal device is handed over frequently between a 4G network and a 5G network, transmission resource overhead increases and performance consumption of the network device increases.

In view of this, an embodiment of the present application provides a communication method for suppressing frequent handover of a terminal device's serving network between a first network and a second network, thereby reducing transmission resource overhead and performance consumption of the network device.

The following first explains some terms used in the embodiments of the present application. Please note that these explanations are intended to make the embodiments of the present application easier to understand, but should not be considered to limit the scope of protection claimed in the present application.

(1) First communication device, second communication device, and third communication device The device in the communication method provided in the embodiment of the present application may include a first communication device and a second communication device, and may optionally further include a third communication device.

In a possible implementation, the first communication device and the second communication device may be two network elements involved in a signaling interaction procedure corresponding to handing over the serving network of the terminal device from the first network to the second network. For information on the signaling interaction procedure corresponding to handing over the serving network of the terminal device from the first network to the second network, please refer to the 3GPP standard protocol.

For example, the first communication device may be a mobility management network element in the first network, and the second communication device may be an access network element in the first network. In another example, the first communication device may be a mobility management network element in the second network, and the second communication device may be an access network element in the second network. In another example, the first communication device may be a mobility management network element in the second network, and the second communication device may be a mobility management network element in the first network. In another example, the first communication device may be a mobility management network element in the first network, and the second communication device may be a mobility management network element in the second network. Optionally, the third communication device may be an access network element in the first network.

For example, when the first network is a 4G network and the second network is a 5G network, the first communication device may be an MME and the second communication device may be an eNB, or the first communication device may be an MME and the second communication device may be an AMF. Optionally, the third communication device is an eNB.

In another example, when the first network is a 5G network and the second network is a 4G network, the first communication device may be an AMF and the second communication device may be a gNB, or the first communication device may be an AMF and the second communication device may be an MME. Optionally, the third communication device is a gNB.

In yet another possible implementation, the first communication device may be a third-party network element, and the second communication device may be a network element associated with a signaling interaction procedure corresponding to handing over the serving network of the terminal device from the first network to the second network. For example, the second communication device may be a mobility management network element in the first network or the second network.

For example, when the first network is a 4G network and the second network is a 5G network, the first communication device may be an NWDAF network element, and the second communication device may be an MME or AMF.

(2) First Period The first period may be understood as one of multiple time windows maintained by the first communication device. For example, the multiple time windows may include time window 1, time window 2, ..., and time window p, where p is a positive integer. The end of time window 1 may be the start of time window 2, and the rest may be estimated by analogy. For example, the start of time window 1 may be the power-on time of the first communication device.

The duration of the first period may be pre-agreed upon in the protocol, pre-configured in the first communication device, or may be a default. This is not a limitation in the embodiments of the present application.

(3) First Area: The coverage area of the first network or the second network may include multiple areas, and the first area may be one of the multiple areas. The multiple areas may be obtained through classification in multiple possible classification schemes.

In a possible implementation, the first area may include at least one of an area corresponding to one or more public land mobile networks (PLMNs), an area corresponding to one or more tracking areas (TAs), and an area corresponding to one or more cells.

(4) First Terminal Type The first terminal type may be a terminal device of one of a plurality of terminal types, and the plurality of terminal types may be obtained through classification in a plurality of possible classification schemes.

In a possible implementation, multiple terminal types may be obtained through classification based on the identifier of the terminal device. For example, the identifier of the terminal device may include at least one of an international mobile equipment identity (IMEI), a user number (e.g., a mobile station international ISDN number (MSISDN)), an international mobile subscriber identity (IMSI), a subscriber permanent identifier (SUPI), and a generic public subscription identifier (GPSI). For example, the IMEI of a terminal device includes 15 digits. For example, different terminal types may be classified based on the first few digits of the 15 digits.

In yet another possible implementation, the multiple terminal types may be obtained through classification based on the device type of the terminal device. For example, the multiple terminal types may include a smartphone, an electric meter, an in-vehicle device, etc.

(5) First-Type Request Message The first-type request message is used to request a handover of a terminal device's serving network from a first network to a second network. When the terminal device registers with the first network, the serving network of the terminal device is the first network. When the terminal device registers with the second network, the serving network of the terminal device is the second network. For example, handing over the serving network of the terminal device from the first network to the second network may include handing over the serving cell of the terminal device from a cell of the first network to a cell of the second network, or reselecting the camping cell of the terminal device from a cell of the first network to a cell of the second network. It will be understood that handing over the serving network of the terminal device from the first network to the second network may further include other possible cases, such as relocating the terminal device from a cell of the first network to a cell of the second network.

(5.1) In a possible implementation, the message name of the first type request message may be the message name of a request message in a signaling interaction procedure corresponding to "handing over the serving network of a terminal device from a first network to a second network." For example, the message name of the first type request message is a handover request message. In another example, the message name of the first type request message is a forward relocation request message. In another example, the message name of the first type request message is a registration request message, e.g., a mobility registration request message. In another example, the message name of the first type request message is a context request message. In another example, the message name of the first type request message is a tracking area update request message.

The context request message is used as an example for the "forward relocation request message," "registration request message," "context request message," "tracking area update request message," etc. Typically, the context request message is used to request the context of a terminal device. Since the context request message is a request message in a signaling interaction procedure corresponding to "handing over the serving network of a terminal device from a first network to a second network," in an embodiment of the present application, the context request message may alternatively be considered to be used to request handing over the serving network of a terminal device from a first network to a second network.

(5.2) In yet another possible implementation form, after a third-party network element (e.g., an NWDAF network element) is introduced into an embodiment of the present application, some new signaling interactions may be introduced in the process of "handing over the serving network of a terminal device from a first network to a second network." In this case, the message name of the first type request message may be the message name of the request message in the newly introduced signaling interactions.

For example, in a process in which a serving cell of a terminal device is handed over from a cell of a first network to a cell of a second network, a mobility management network element in the first network may send a handover notification request message to a third-party network element to request the third-party network element to enable the serving cell of the terminal device to be handed over from the cell of the first network to the cell of the second network. After receiving the handover notification request message, the third-party network element may return a handover notification response message so that the mobility management network element in the first network can perform subsequent procedures based on the handover notification response message. The "handover notification request message" and "handover notification response message" in this specification are newly introduced signaling interactions, and the message name of the first type of request message may be a "handover notification request message."

The specific scenario in which the mobility management network element in the first network sends the handover notification request message is not limited to the embodiments of the present application. For example, see FIG. 1B. In method 1, the access network element in the first network may send a handover request message to the mobility management network element in the first network. After receiving the handover request message, the mobility management network element in the first network may send a handover notification request message to the third-party network element. In method 2, the access network element in the first network may send a handover request message to the mobility management network element in the first network. After receiving the handover request message, the mobility management network element in the first network may send a forward relocation request message to the mobility management network element in the second network. After receiving a forward relocation response message from the mobility management network element in the second network, the mobility management network element in the first network sends a handover notification request message to the third-party network element.

In another example, in a process in which a serving cell of a terminal device is handed over from a cell of a first network to a cell of a second network, a mobility management network element in the second network may send a handover notification request message to a third-party network element. After receiving the handover notification request message, the third-party network element may return a handover notification response message so that the mobility management network element in the second network can perform subsequent procedures based on the handover notification response message. The "handover notification request message" and "handover notification response message" in this specification are newly introduced signaling interactions, and the message name of the first type of request message may be a "handover notification request message."

The specific scenario in which the mobility management network element in the second network sends a handover notification request message is not limited to the embodiments of the present application. For example, see FIG. 1B. In method 3, an access network element in the first network may send a handover request message to a mobility management network element in the first network. After receiving the handover request message, the mobility management network element in the first network may send a forward relocation request message to a mobility management network element in the second network. After receiving the forward relocation request message, the mobility management network element in the second network may send a handover notification request message to a third-party network element.

In another example, in a process in which a camping cell of a terminal device is reselected from a cell of a first network to a cell of a second network, a mobility management network element in the second network may send a reselection notification request message to a third-party network element to request the third-party network element to enable the camping cell of the terminal device to be reselected from the cell of the first network to a cell of the second network. After receiving the reselection notification request message, the third-party network element may return a reselection notification response message so that the mobility management network element in the second network can perform subsequent procedures based on the reselection notification response message. The "reselection notification request message" and "reselection notification response message" in this specification are newly introduced signaling interactions, and the message name of the first type of request message may be "reselection notification request message."

The specific scenario in which the mobility management network element in the second network sends the reselection notification request message is not limited to the embodiments of the present application. For example, see FIG. 1C. In method 4, the access network element in the second network may send a tracking area update request message or a registration request message to the mobility management network element in the second network. The tracking area update request message or the registration request message may carry an identifier (or indication information or status information), where the identifier indicates that the terminal device has previously registered with the 4G network. After receiving the tracking area update request message or the registration request message, the mobility management network element in the second network may send a reselection notification request message to the third-party network element. In method 5, after receiving the tracking area update request message or the registration request message, the mobility management network element in the second network may send a context request message to the mobility management network element in the first network. After receiving the context response message, the mobility management network element in the second network sends a reselection notification request message to the third-party network element.

In another example, in a process in which a camping cell of a terminal device is reselected from a cell of a first network to a cell of a second network, a mobility management network element in the first network may send a reselection notification request message to a third-party network element. After receiving the reselection notification request message, the third-party network element may return a reselection notification response message so that the mobility management network element in the first network can perform subsequent procedures based on the reselection notification response message. The "reselection notification request message" and "reselection notification response message" in this specification are newly introduced signaling interactions, and the message name of the first type of request message may be "reselection notification request message."

The specific scenario in which the mobility management network element in the first network sends a reselection notification request message is not limited in the embodiments of the present application. For example, see FIG. 1C. In method 6, the access network element in the second network may send a context request message to the mobility management network element in the first network. After receiving the context request message, the mobility management network element in the first network may send a reselection notification request message to the third-party network element.

It will be understood that the "handover notification request message," "handover notification response message," "reselection notification request message," and "reselection notification response message" may alternatively be replaced with other possible message names. For example, the "handover notification request message" and "reselection notification request message" may be replaced with the "user registration notification request message," and the "handover notification response message" and "reselection notification response message" may be replaced with the "user registration notification response message."

Below, several possible implementations of the first type of request message are described with reference to Examples 1 to 5.

Example 1: A first type of request message may correspond to a specific terminal device (e.g., terminal device 1). Upon receiving a request message (e.g., a first request message), the first communication device may determine whether the first request message belongs to the first type of request message. For example, if the first request message is used to request a handover of the serving network of terminal device 1 from a first network to a second network, the first communication device may determine that the first request message belongs to the first type of request message.

Example 2: A first type request message may correspond to a specific terminal device (e.g., terminal device 1) located within the first area. In this case, the first type request message may include first information, where the first information indicates that the terminal device is located within the first area. Upon receiving a request message (e.g., the first request message), the first communication device may determine whether the first request message belongs to the first type request message. For example, if the first request message includes the first information and is used to request a handover of the serving network of terminal device 1 from the first network to the second network, the first communication device may determine that the first request message belongs to the first type request message.

For example, the first information may include at least one of an identifier of a cell in which the terminal device 1 is located, an identifier of a tracking area, and an identifier of a PLMN. Classification rules for different areas may be pre-agreed upon in a protocol or pre-configured in the first communication device. For example, the first area includes an area corresponding to cell 1 and an area corresponding to cell 2. After the first communication device receives the first request message, if the first information includes the identifier of cell 1 (i.e., if the terminal device 1 is located within cell 1), the area corresponding to cell 1 belongs to the first area, and therefore the first communication device may determine that the terminal device 1 is located within the first area.

Example 3: A first type request message may correspond to terminal devices of a first terminal type. For example, if the terminal devices of the first terminal type include terminal device 1, terminal device 2, and terminal device 3, the first type request message may correspond to terminal device 1, terminal device 2, and terminal device 3. In this case, the first type request message may include second information, where the second information indicates that the type of the terminal device (e.g., terminal device 1, terminal device 2, or terminal device 3) is the first terminal type. Upon receiving a request message (e.g., a first request message), the first communication device may determine whether the first request message belongs to the first type request message. For example, if the first request message includes second information, where the second information indicates that the type of terminal device 1 is the first terminal type, and the first request message is used to request a handover of the serving network of terminal device 1 from the first network to the second network, the first communication device may determine that the first request message belongs to the first type request message. Alternatively, if the first request message includes second information, the second information indicates that the type of the terminal device 2 is a first terminal type, and the first request message is used to request a handover of the serving network of the terminal device 2 from the first network to the second network, the first communication device may determine that the first request message belongs to the first type of request message.

For example, classification rules for different terminal types may be pre-agreed upon in a protocol or pre-configured in the first communication device. In an example in which the first terminal type is obtained through classification based on a terminal device identifier, when the first request message is used to request reselection of the terminal device's camping cell from a cell of the first network to a cell of the second network, the second information may include the terminal device identifier so that the first communication device can determine the terminal type of the terminal device based on the terminal device identifier and the classification rule. When the first request message is used to hand over the terminal device's serving cell from a cell of the first network to a cell of the second network, the second information may include the terminal device's temporary identifier. The first communication device may obtain the terminal device identifier based on the terminal device's temporary identifier and then determine the terminal type of the terminal device based on the terminal device identifier and the classification rule.

Example 4: A first type request message may correspond to a terminal device located within a first area. For example, if the terminal devices located within the first area include terminal device 1 and terminal device 2, the first type request message may correspond to terminal device 1 and terminal device 2. In this case, the first type request message may include first information, and the first information indicates that the terminal device (e.g., terminal device 1 or terminal device 2) is located within the first area. Upon receiving a request message (e.g., the first request message), the first communication device may determine whether the first request message belongs to the first type request message. For example, if the first request message includes first information and is used to request a handover of the serving network of the terminal device (e.g., terminal device 1 or terminal device 2) from the first network to the second network, the first communication device may determine that the first request message belongs to the first type request message.

Example 5: A first type request message may correspond to a terminal device located within a first area and whose type is a first terminal type. For example, if the terminal devices located within the first area and whose type is a first terminal type include terminal device 1 and terminal device 2, the first type request message may correspond to terminal device 1 and terminal device 2. In this case, the first type request message may include first information and second information, where the first information indicates that the terminal device (e.g., terminal device 1 or terminal device 2) is located within the first area, and the second information indicates that the terminal device (e.g., terminal device 1 or terminal device 2) is of the first terminal type. Upon receiving a request message (e.g., a first request message), the first communication device may determine whether the first request message belongs to the first type request message. For example, if a first request message includes first information and second information, where the first information indicates that terminal device 1 is located within a first area and the second information indicates that the type of terminal device 1 is a first terminal type, and the first request message is used to request a handover of the serving network of terminal device 1 from a first network to a second network, the first communication device may determine that the first request message belongs to the first type of request message.

In other words, the first type of request message may correspond to one terminal device (e.g., Examples 1 and 2), or may correspond to multiple terminal devices (e.g., Examples 3, 4, and 5).

(6) Registration In a wireless communication network, a terminal device needs to register to access the network. The registration process may include authentication, secure connection establishment, bearer establishment, etc. In a 4G network, a terminal device may send a tracking area update request message or an attach request message to a core network element via an access network element to complete registration to the 4G network. The attach request message may also be referred to as a registration request message, and "a terminal device registers to a 4G network" may also be referred to as "a terminal device connects to a 4G network." In a 5G network, a terminal device may send a tracking area update request message or a registration request message to a core network element via an access network element to complete registration to the 5G network. In a 5G network, the tracking area update request message may also be referred to as a mobility registration request message.

Based on the above, the communication method provided in the embodiment of the present application will now be described in detail with reference to the accompanying drawings.

Figure 2 is a schematic flowchart of a communication method according to one embodiment of the present application. As shown in Figure 2, the method includes the following steps:

S201: A second communication device transmits a first request message to a first communication device, and in response, the first communication device receives a first request message from the second communication device during a first period, where the first request message belongs to a first type of request message.

In this specification, there may be multiple cases, such as Cases 1 to 12, in which a second communication device transmits a first request message to a first communication device. For ease of explanation, this embodiment uses an example in which the first type of request message corresponds to a first terminal device or corresponds to a first terminal device located in a first area. In Cases 1, 2, 5, 6, 9, and 10, the first type of request message is used to request a handover of the serving cell of the first terminal device from a cell of the first network to a cell of the second network. In Cases 3, 4, 7, 8, 11, and 12, the first type of request message is used to request a reselection of the camping cell of the first terminal device from a cell of the first network to a cell of the second network. The first network may be a 4G network and the second network may be a 5G network, or the first network may be a 5G network and the second network may be a 4G network.

(1) Case 1: The first communication device may be an MME, the second communication device may be an eNB, and the first type of request message may be a handover request message.

For example, after accessing a 4G network, the first terminal device may measure the received signal quality of a serving cell (e.g., a cell of the eNB accessed by the first terminal device) and a neighboring cell of the first terminal device to obtain an indicator of the received signal quality of the serving cell and the neighboring cell. When the reporting condition of Event A3 is met, the first terminal device reports a measurement report to the eNB. Correspondingly, after receiving the measurement report, the eNB determines, based on the measurement report, that the serving cell of the first terminal device needs to be handed over from a cell of the 4G network to a cell of the 5G network. Then, a first request message (i.e., a handover request message) may be sent to the MME.

For example, the handover request message may include location information of the target cell. For example, the location information of the target cell may include an identifier of a tracking area corresponding to the target cell, an identifier of the target cell, an identifier of a base station corresponding to the target cell, etc. Based on the location information of the target cell, the first communication device may identify that the target cell is a cell of a 5G network, and further determine that the handover request message is used to request a handover of the serving cell of the first terminal device from a cell of the 4G network to a cell of the 5G network.

(2) Case 2: The first communication device may be an AMF, the second communication device may be an MME, and the first type of request message may be a forwarding relocation request message.

For example, the forwarding relocation request message may include a "RAT Type" information element. When the value of the information element is LTE, this indicates that the forwarding relocation request message is from an MME of a 4G network. Therefore, based on the "RAT Type" information element, the first communication device may determine that the forwarding relocation request message is used to request a handover of the serving cell of the first terminal device from a cell of the 4G network to a cell of the 5G network.

(3) Case 3: The first communication device may be an AMF, the second communication device may be a gNB, and the first type of request message may be a registration request message or a tracking area update request message.

For example, a registration request message is used as an example. The registration request message may include registration type information and status information of the first terminal device. The registration type information indicates that the registration type is mobility registration, and the status information of the first terminal device indicates that the first terminal device registers with a 4G network. Therefore, based on the registration type information and the status information of the first terminal device, the first communication device may determine that the registration request message is used to request reselection of the camping cell of the first terminal device from a cell of the 4G network to a cell of the 5G network.

(4) Case 4: The first communication device may be an MME, the second communication device may be an AMF, and the first type of request message may be a context request message.

For example, the context request message may include an identifier of the target network (e.g., an identifier of a 5G network). Thus, the first communication device may determine, based on the identifier of the target network, that the context request message is used to reselect the camping cell of the first terminal device from a cell of the 4G network to a cell of the 5G network. There may be multiple implementation forms in which the context request message includes the identifier of the target network. For example, the context request message includes a "RAT Type" information element. When the value of the information element is NR, this indicates that the target network is a 5G network. In another example, the context request message includes a "Control Plane Fully Qualified TEID" information element. When the information element carries "N26 AMF GTP-C interface," this indicates that the target network is a 5G network.

(5) Case 5: The first communication device may be an AMF, the second communication device may be a gNB, and the first type of request message may be a handover request message.

For example, the handover request message may include an identifier of a target cell (e.g., a cell of a 4G network). Therefore, the first communication device may determine, based on the identifier of the target cell, that the handover request message is used to hand over the serving cell of the first terminal device from a cell of the 5G network to a cell of the 4G network.

(6) Case 6: The first communication device may be an MME, the second communication device may be an AMF, and the first type request message may be a forwarding relocation request message.

For example, the forward relocation request message may include an identifier of the target network (e.g., an identifier of the 5G network). Thus, the first communication device may determine, based on the identifier of the target network, that the context request message is used to hand over the serving cell of the first terminal device from a cell of the 5G network to a cell of the 4G network. There may be multiple implementation forms in which the forward relocation request message includes the identifier of the target network. For example, the forward relocation request message may include a "RAT Type" information element. When the value of the information element is NR, this indicates that the forward relocation request message is from the AMF of the 5G network. Alternatively, the context request message includes a "Control Plane Fully Qualified TEID" information element. When the information element carries "N26 AMF GTP-C interface," this indicates that the forward relocation request message is from the AMF of the 5G network.

(7) Case 7: The first communication device may be an MME, the second communication device may be an eNB, and the first type of request message may be a tracking area update request message or a registration request message.

For example, a tracking area update request message is used as an example. The tracking area update request message may include information instructing the first terminal device to reselect a 4G network and may further include status information of the first terminal device. The status information of the first terminal device indicates that the first terminal device will register with a 5G network. Therefore, based on the information included in the tracking area update request message, the first communication device may determine that the tracking area update request message is used to request reselection of the camping cell of the first terminal device from a cell of the 5G network to a cell of the 4G network.

(8) Case 8: The first communication device may be an AMF, the second communication device may be an MME, and the first type of request message may be a context request message.

For example, the context request message may include an identifier of the target network (e.g., an identifier of a 4G network). Therefore, the first communication device may determine, based on the identifier of the target network, that the context request message is used to reselect the camping cell of the first terminal device from a cell of the 5G network to a cell of the 4G network.

(9) Case 9: The first communication device may be an NWDAF, the second communication device may be a mobility network element in the first network, and the first type of request message may be a handover notification request message.

For example, the first network is a 4G network, the second network is a 5G network, and the second communication device is an MME in the 4G network. The MME may send a first request message (i.e., a handover notification request message) to the NWDAF to request the NWDAF to enable the serving cell of the terminal device to be handed over from a cell of the 4G network to a cell of the 5G network. For details, see Method 1 or Method 2 of FIG. 1B.

(10) Case 10: The first communication device may be an NWDAF, the second communication device may be a mobility network element in the second network, and the first type of request message may be a handover notification request message.

For example, the first network is a 4G network, the second network is a 5G network, and the second communication device is an AMF in the 5G network. The AMF may send a first request message (i.e., a handover notification request message) to the NWDAF to request the NWDAF to enable the serving cell of the terminal device to be handed over from a cell of the 4G network to a cell of the 5G network. For details, see scheme 3 in FIG. 1B.

(11) Case 11: The first communication device may be an NWDAF, the second communication device may be a mobility network element in the second network, and the first type of request message may be a reselection notification request message.

For example, the first network is a 4G network, the second network is a 5G network, and the second communication device is an AMF in the 5G network. The AMF may send a first request message (i.e., a reselection notification request message) to the NWDAF to request the NWDAF to allow the camping cell of the terminal device to be reselected from a cell of the 4G network to a cell of the 5G network. For details, see Method 4 or Method 5 of FIG. 1C.

(12) Case 12: The first communication device may be an NWDAF, the second communication device may be a mobility network element in the first network, and the first type of request message may be a user registration notification request message (or a reselection notification request message).

For example, the first network is a 4G network, the second network is a 5G network, and the second communication device is an MME in the 4G network. The MME may send a first request message (i.e., a reselection notification request message) to the NWDAF to request the NWDAF to allow the camping cell of the terminal device to be reselected from a cell of the 4G network to a cell of the 5G network. For details, see scheme 6 in FIG. 1C.

S202: When the quality of the first type of request message received during the first period is higher than a first threshold, the first communication device transmits first instruction information to the second communication device, the first instruction information indicating that the request of the first request message is to be rejected.

In a possible implementation, the first communication device may obtain statistical information corresponding to the first type of request messages during a first period of time and determine, based on the statistical information, whether the quality of the first type of request messages received during the first period of time is higher than a first threshold. The first threshold may be pre-agreed upon in a protocol, pre-configured in the first communication device, or may be a default.

In one example, the statistical information may include the number of request messages of a first type received during a first period. Each time the first communication device receives a request message of the first type during the first period, the first communication device may add 1 to the statistical information. For example, after receiving the first request message, the first communication device may add 1 to the statistical information and determine whether the cumulative number is greater than a first threshold. If the cumulative number is greater than the first threshold, the first communication device may determine that the first request message is an abnormal message (optionally, the first communication device may further determine that all request messages of the first type subsequently received during the first period are abnormal messages) and transmit first instruction information. In other words, in the case of an abnormal message, subsequent procedures corresponding to "handing over the serving network of the terminal device from the first network to the second network" are no longer performed. If the cumulative number is less than or equal to the first threshold, the implementation is performed according to the prior art. For example, the request of the first request message may be accepted, i.e., subsequent procedures corresponding to "handing over the serving network of the terminal device from the first network to the second network" continue to be performed.

In this embodiment of the present application, the first communication device may transmit the first instruction information to the second communication device in multiple ways. Below, we will describe several possible implementation forms in which the first communication device transmits the first instruction information to the second communication device, with reference to Cases 1 to 12.

(1) In case 1, the MME may send a handover preparation failure message to the eNB, where the handover preparation failure message includes the first indication information.

(2) In case 2, the AMF may send a forward relocation response message to the MME, where the forward relocation response message includes first indication information. Further, after receiving the first indication information, the MME may forward the first indication information to the eNB.

In Case 1 and Case 2, the first indication information indicating a rejection of the request in the first request message may mean that the first indication information indicates a rejection of the handover of the serving cell of the first terminal device from a cell of the 4G network to a cell of the 5G network. For example, the first indication information may be a handover failure cause value defined in the 3GPP standard protocol.

(3) In case 3, the AMF may send a registration reject message to the gNB, where the registration reject message includes first indication information. In this case, the first indication information indicating a rejection of the request of the first request message may mean that the first indication information indicates a rejection of registration of the first terminal device to the 5G network (or may be considered as a rejection of reselection of the camping cell of the first terminal device from a cell of the 4G network to a cell of the 5G network). For example, the first indication information may be a registration failure cause value defined in a 3GPP standard protocol.

(4) In case 4, the MME may send a Context Response message to the AMF, where the context response message includes first indication information. In this case, the first indication information indicating a rejection of the request of the first request message means that the first indication information indicates a rejection of the AMF's context request (or may be considered as a rejection of reselection of the camping cell of the first terminal device from a cell of the 4G network to a cell of the 5G network).

(5) In case 5, the AMF may send a handover preparation failure message to the gNB, where the handover preparation failure message includes the first indication information.

(6) In case 6, the MME may send a forwarding relocation response message to the AMF, where the forwarding relocation response message includes the first indication information.

In Cases 5 and 6, the first instruction information indicating a denial of the request in the first request message may mean that the first instruction information indicates a denial of handover of the serving cell of the first terminal device from a cell of the 5G network to a cell of the 4G network.

(7) In case 7, the MME may send a TAU reject message to the eNB, where the TAU reject message includes first indication information. In this case, the first indication information indicating a rejection of the request of the first request message may mean that the first indication information indicates a rejection of reselection of the camping cell of the first terminal device from the cell of the 5G network to the cell of the 4G network.

(8) In case 8, the AMF may send a context response message to the MME, where the context response message includes first indication information. In this case, the first indication information indicating a denial of the request of the first request message may mean that the first indication information indicates a denial of providing the context of the first terminal device for the MME (or may be considered as a denial of reselection of the camping cell of the first terminal device from a cell of the 5G network to a cell of the 4G network).

(9) In case 9, the NWDAF may send a handover notification response message to a mobility network element in the first network, where the handover notification response message includes the first indication information.

(10) In case 10, the NWDAF may send a handover notification response message to a mobility network element in the second network, where the handover notification response message includes the first indication information.

(11) In case 11, the NWDAF may send a reselection notification response message to a mobility network element in the second network, where the reselection notification response message includes the first indication information.

(12) In case 12, the NWDAF may send a reselection notification response message to a mobility network element in the first network, where the reselection notification response message includes the first indication information.

Optionally, the method may further include the following steps:

S203: The second communication device sends a second request message to the first communication device, and in response, the first communication device receives the second request message during a second period, where the second request message belongs to a first type of request message.

For example, after determining that the first request message is an abnormal message, the first communication device may add the first terminal device to a blacklist and use the time point at which the first instruction information is transmitted as the start time point of the second period. For example, the first communication device may start a timer when transmitting the first instruction information, and the duration of the timer may be equal to the duration of the second period.

After receiving the second request message during the second period, the first communication device may perform any one of S204a, S204b, and S204c.

S204a: The first communication device discards the second request message.

S204b: The first communication device transmits second instruction information to the second communication device, the second instruction information indicating that a request for the second request message is prohibited.

S204c: The first communication device sends third instruction information to the third communication device, the third instruction information indicating de-registration of the first terminal device from the first network.

Below, S204a, S204b, and S204c are explained with reference to Cases 1 to 12.

(1) In cases 1 to 12, after receiving the second request message, the first communication device may determine that the second request message is the first request message of the first type received during the second period and may transmit second instruction information (i.e., execute S204b).

For example, in case 1, the MME may send a UE context modification request to the eNB, where the UE context modification request message includes the second indication information. In case 2, the AMF may send a forwarding relocation response message to the MME, where the forwarding relocation response message includes the second indication information. In case 5, the AMF may send a UE context modification request message to the gNB, where the UE context modification request message includes the second indication information. In case 6, the MME sends a forwarding relocation response message to the AMF, where the forwarding relocation response message includes the second indication information. In case 9, the NWDAF may send a handover notification response message to a mobility network element in the first network, where the handover notification response message includes the second indication information. In case 10, the NWDAF may send a handover notification response message to a mobility network element in the second network, where the handover notification response message includes the second indication information.

Case 1 is used as an example. When the first type request message corresponds to a first terminal device, the second instruction information indicating prohibiting the request for the second request message may mean that the second instruction information indicates that the serving cell of the first terminal device is prohibited from being handed over from a cell of the 4G network to a cell of the 5G network. In one example, the second instruction information may be a mobility restriction list, which may include restriction information corresponding to one or more networks. For example, the mobility restriction list may include restriction information corresponding to a 5G network, and the restriction information corresponding to the 5G network indicates that the serving cell of the first terminal device is prohibited from being handed over to a cell of the 5G network. Correspondingly, after receiving the second instruction information, if the eNB prohibits the request for the second request message based on the second instruction information (i.e., prohibits the serving cell of the first terminal device from being handed over from a cell of the 4G network to a cell of the 5G network), the eNB will no longer send the first type request message to the MME thereafter. If the eNB does not prohibit the request for the second request message based on the second indication information, the eNB may then send a first type request message to the MME.

When the first type request message corresponds to a first terminal device located within the first area, the second instruction information indicating that the request of the second request message is prohibited may mean that the second instruction information indicates that the serving cell of the first terminal device is prohibited from being handed over from a cell of the 4G network to a cell of the 5G network when the first terminal device is located within the first area.

In case 3, the AMF may send a registration response message to the gNB, where the registration response message includes the second indication information. In case 4, the MME may send a context response message to the AMF, where the context response message includes the second indication information. In case 7, the MME may send a TAU response message to the eNB, where the TAU response message includes the second indication information. In case 8, the AMF may send a context response message to the MME, where the context response message includes the second indication information. In case 11, the NWDAF may send a reselection notification response message to a mobility network element in the second network, where the reselection notification response message includes the second indication information. In case 12, the NWDAF may send a reselection notification response message to a mobility network element in the first network, where the reselection notification response message includes the second indication information.

Case 3 is used as an example. When the first type request message corresponds to a first terminal device, the second instruction information indicating that the request of the second request message is prohibited may mean that the second instruction information indicates that the camping cell of the first terminal device is prohibited from being reselected from a cell of the 4G network to a cell of the 5G network. When the first type request message corresponds to a first terminal device located in a first area, the second instruction information indicating that the request of the second request message is prohibited may mean that the second instruction information indicates that the camping cell of the first terminal device is prohibited from being reselected from a cell of the 4G network to a cell of the 5G network when the first terminal device is located in the first area.

(2) Cases 4 and 8 are used as examples. After receiving the second request message, if the first communication device determines that the second request message is the first request message of the first type received in the second period, the first communication device may send third instruction information to the third communication device (i.e., execute S204c).

For example, in case 4, the third communication device may be an eNB, and the MME may send third instruction information to the eNB. The third instruction information indicates deregistering the first terminal device from the 4G network (to avoid subsequent reselection of the first terminal device's camping cell from a cell of the 4G network to a cell of the 5G network). In response, the eNB may receive the third instruction information and forward the third instruction information to the first terminal device. If the first terminal device successfully deregisters from the 4G network, the eNB may not subsequently send a first type request message from the MME. If the first terminal device fails to deregister from the 4G network, the eNB may subsequently further send a first type request message from the MME.

In case 8, the third communication device may be a gNB, and the AMF may send third instruction information to the gNB. The third instruction information indicates deregistering the first terminal device from the 4G network (to avoid subsequent reselection of the camping cell of the first terminal device from a cell of the 5G network to a cell of the 4G network). In response, the gNB may receive the third instruction information and forward the third instruction information to the first terminal device. If the first terminal device successfully deregisters from the 5G network, the gNB may not subsequently send a first type request message from the AMF. If the first terminal device fails to deregister from the 5G network, the gNB may subsequently further send a first type request message from the AMF.

It will be understood that in some cases other than Case 4 and Case 8, the first communication device may also transmit the third indication information to the second communication device. For example, in Case 11, the NWDAF may transmit the third indication information to a mobility network element in the second network, which may transmit the third indication information to a mobility network element in the first network, which may transmit the third indication information to an access network element in the first network. Thus, the access network element in the first network may forward the third indication information to the terminal device. In another example, in Case 12, the NWDAF may transmit the third indication information to a mobility network element in the first network, which may forward the third indication information to an access network element in the first network. Thus, the access network element in the first network may forward the third indication information to the terminal device.

(3) Cases 3 and 7 are used as examples. Upon receiving a second request message during the second period, the first communication device discards the second request message (i.e., executes S204a).

In addition, after sending the second request message to the first communication device, the second communication device may further send a third request message. Correspondingly, if the first communication device receives the third request message during the second period, the third request message may belong to the first type of request message and be discarded.

For example, in Case 1, Case 2, Case 4, Case 5, Case 6, Case 8, and Cases 9 to 12, after receiving the third request message, if the first communication device determines that the third request message is the nth first type request message received in the second period, where n is an integer greater than 1, the third request message may be discarded. In Cases 3 and 7, when the first communication device receives the third request message in the second period, it may discard the third request message.

It will be understood that at the end of the second period, the first communication device may remove the first terminal device from the blacklist. Additionally, if the first communication device sends second instruction information to the second communication device in S204, the first communication device may send fourth instruction information to the second communication device at the end of the second period. The fourth instruction information indicates that the request for the second request message is permitted.

According to this method, statistics are collected regarding the number of first-type request messages within a first period. When the number of first-type request messages is greater than a first threshold, subsequent procedures corresponding to "handing over the serving network of the first terminal device from the first network to the second network" may not be performed, effectively suppressing frequent handovers of the serving network of the first terminal device between the first network and the second network. This reduces transmission resource overhead and reduces performance consumption of the network device. Furthermore, objects corresponding to first-type request messages may be flexibly configured. For example, a first-type request message may correspond to a specific terminal device or to a specific terminal device within a specific area. This allows for more precise control and can meet the requirements of multiple scenarios.

In addition, (1) in this embodiment of the present application, an example in which statistics on the number of first-type request messages within a first period are collected is used for explanation. In another possible embodiment, statistics on the number of first-type response messages within a first period may also be collected to determine whether to execute the subsequent procedure of "handing over the serving network of the first terminal device from the first network to the second network" based on the statistical information. For example, after the number of first-type response messages received by the first communication device within the first period is greater than a first threshold, the subsequent procedure of "handing over the serving network of the first terminal device from the first network to the second network" is no longer executed. The message name of the first-type response message may be the message name of a response message in a signaling interaction procedure corresponding to "handing over the serving network of the terminal device from the first network to the second network." For example, the message name of the first-type response message may be a context response message. In another example, the message name of the first-type response message may be a forwarding relocation response message.

(2) Typically, after the serving network of a first terminal device is handed over from the first network to the second network, a network element in the first network deletes information related to the first terminal device. In this embodiment of the present application, if the first communication device is a network element in the first network, after the serving network of the first terminal device is handed over from the first network to the second network, the first communication device may not delete information related to the first terminal device. For example, the first communication device may not delete statistical information corresponding to a first type of request message within a first period. In other words, after the serving network of the first terminal device is handed over from the first network to the second network, the first communication device still stores statistical information corresponding to a first type of request message within a first period. The specific duration for which the first communication device stores statistical information corresponding to a first type of request message within a first period may be preconfigured. This is not particularly limited.

For example, assume that the first communication device is an MME, the first network is a 4G network, and the second network is a 5G network. See FIG. 3A. After the MME receives the third first-type request message in the first period, the statistical information is 3. The MME accepts the third first-type request message so that the serving network of the first terminal device is handed over from the 4G network to the 5G network. In this case, although the serving network of the first terminal device is handed over to the 5G network, the MME does not need to delete the statistical information corresponding to the first-type request message in the first period. Subsequently, if the MME receives a first-type request message in the first period after the serving network of the first terminal device is handed over from the 5G network to the 4G network, 1 may be added to the previously stored statistical information (i.e., 3) so that the serving network of the first terminal device is effectively prevented from being handed over between the 4G network and the 5G network.

The steps shown in Figure 2 are merely possible steps. The step numbers in Figure 2 are merely an example of an execution procedure and do not constitute limitations on the execution order of the steps. In this embodiment of the present application, there is no strict execution order between steps that do not have chronological dependencies with each other. Not all steps shown in the flowchart are required. Some steps may be deleted from the flowchart based on actual requirements, or other possible steps may be added to the flowchart based on actual requirements.

With reference to Figures 3A to 3D, the following describes, from the perspective of the first communication device, several ways of processing a first type of request message received by the first communication device.

As shown in FIG. 3A, the first threshold is assumed to be 5. After the first communication device receives the first first-type request message in the first period, the statistical information is 1, and the first communication device may accept the request for the first first-type request message. After the first communication device receives the second first-type request message in the first period, the statistical information is 2, and the first communication device may accept the request for the second first-type request message. The rest can be deduced by analogy. After the first communication device receives the sixth first-type request message (i.e., the first request message) in the first period, the statistical information is 6 (greater than the first threshold), and the first communication device may send first instruction information to the second communication device and start Timer 1. The duration of Timer 1 is the duration of the second period.

After the first communication device receives the seventh first-type request message in the first period, the statistical information is 7, and the seventh first-type request message is the first first-type request message received by the first communication device in the second period, so that the second or third instruction information can be transmitted. After the first communication device receives the eighth first-type request message in the first period, the statistical information is 8, and the eighth first-type request message is not the first first-type request message received by the first communication device in the second period, so that the eighth first-type request message can be discarded. Similarly, if the first communication device receives the ninth first-type request message in the first period, the ninth first-type request message can be discarded. It will be understood that at the end of the second period, the first communication device can transmit the fourth instruction information.

After the first communication device receives the tenth first-type request message in the first period, the statistical information is 10 (greater than the first threshold), and the first communication device may send first indication information to the second communication device and start Timer 2. The duration of Timer 2 is the duration of the second period. If the first communication device receives a first-type request message before Timer 2 expires, please refer to the description corresponding to Timer 1 for specific implementation forms.

The difference between the implementation shown in FIG. 3B and the implementation shown in FIG. 3A is that in FIG. 3B, the first communication device does not need to send the second instruction information or the third instruction information. In other words, if the first communication device receives a first type request message during the second period, the first communication device may discard the first type request message.

The difference between the implementation shown in FIG. 3C and the implementation shown in FIG. 3A is that in FIG. 3C, the first communication device does not need to start a timer. In other words, if the first communication device receives the sixth first-type request message (i.e., the first request message) in the first period, the statistical information is 6 (greater than the first threshold), and the first communication device may transmit first indication information to the second communication device. Additionally, if the first communication device receives the seventh first-type request message (i.e., the second request message) in the first period, the first communication device may transmit second indication information or third indication information to the second communication device. Subsequently, if the first communication device receives a first-type request message in the first period, the first communication device may discard the first-type request message.

The difference between the implementation shown in FIG. 3D and the implementation shown in FIG. 3A is that in FIG. 3D, the first communication device may not start a timer or transmit the second instruction information or the third instruction information. In other words, if the first communication device receives the sixth first-type request message (i.e., the first request message) in the first period, the statistical information is 6 (greater than the first threshold), and the first communication device may transmit the first instruction information to the second communication device. Subsequently, if the first communication device receives a first-type request message in the first period, the first communication device may discard the first-type request message.

The difference between the implementation shown in FIG. 3E and the implementation shown in FIG. 3A is that in FIG. 3E, if the first communication device receives a first type request message when the number of first type request messages received in a first period is greater than a first threshold, the first communication device may discard the first type request message.

(1) It will be understood that Case 1, Case 2, Case 4, Case 5, Case 6, Case 8, and Case 9 to Case 12 are applicable to Figures 3A to 3E, and Case 3 and Case 7 are applicable to Figure 3B, Figure 3D, or Figure 3E.

(2) From the above description and Figures 3A and 3B, it can be seen that a first period may include one or more second periods. See Figure 4, for example. The first period includes second period 1 and second period 2, where t1 is the start of the first period, t2 is the start of second period 1, t3 is the start of second period 2, and t4 is the end of the first period. Second period 1 is used as an example. In a possible implementation, at the start of second period 1, if duration T is less than or equal to the remaining duration of the first period (i.e., the duration from t2 to t4), the duration of second period 1 may be equal to T. If T is greater than the remaining duration of the first period (i.e., the duration from t2 to t4), the duration of second period 1 may be equal to the remaining duration of the first period. T may be pre-agreed upon in a protocol, pre-configured in the first communication device, or default.

(3) In the above embodiment, an example is used in which the first type request message corresponds to one terminal device. As described above, the first type request message may also correspond to multiple terminal devices. When the first type request message also corresponds to multiple terminal devices, in a possible implementation form, after the number of first type request messages received in the first period is greater than the first threshold, the first communication device may use the method described in the above embodiment to process the request messages corresponding to each terminal device.

For example, the method shown in FIG. 3A is used to process request messages corresponding to each terminal device. See FIG. 5. A first type of request message corresponds to a terminal device of a first terminal type (e.g., terminal device 1, terminal device 2, and terminal device 3). After the first communication device receives five first type request messages in a first period (the five first type request messages may include a request message corresponding to terminal device 1, a request message corresponding to terminal device 2, and a request message corresponding to terminal device 3), for terminal device 1, if a request message a1 corresponding to terminal device 1 is received and the request message a1 belongs to the first type of request message, indication information a1 may be sent, where the indication information a1 indicates that the request of request message a1 is rejected, and a timer a1 is started (the duration of the timer a1 is the duration of the second period a1). When a request message a2 corresponding to terminal device 1 is received and the request message a2 belongs to a first type of request message, instruction information a2 or instruction information a3 may be sent, where instruction information a2 indicates that the request of request message a2 is prohibited, and instruction information a3 indicates that terminal device 1 is to be deregistered from the first network. Subsequently, when a request message (e.g., request message a3 or request message a4) corresponding to terminal device 1 is received during second period a1, the request message may be discarded.

Optionally, if the first communication device transmits the instruction information a2, the instruction information a4 may be transmitted at the end of the second period a1. The instruction information a4 indicates that the request in the request message a2 is permitted.

It will be understood that the first period may include multiple second periods corresponding to the terminal device 1, such as the second period a2. For implementation forms corresponding to the second period a2, please refer to the description of the second period a1.

For terminal device 2, if a request message b1 corresponding to terminal device 2 is received and the request message b1 belongs to a first type of request message, indication information b1 may be sent, where the indication information b1 indicates that the request of request message b1 is rejected, and timer b1 is started (the duration of timer b1 is the duration of second period b1). If a request message b2 corresponding to terminal device 2 is received and the request message b2 belongs to the first type of request message, indication information b2 or indication information b3 may be sent, where the indication information b2 indicates that the request of request message b2 is prohibited, and the indication information b3 indicates that terminal device 2 is deregistered from the first network. Subsequently, if a request message (e.g., request message b3 or request message b4) corresponding to terminal device 2 is received during the second period b1, the request message may be discarded.

Optionally, if the first communication device transmits the indication information b2, the indication information b4 may be transmitted at the end of the second period b1. The indication information b4 indicates that the request in the request message b2 is permitted.

It will be understood that the first period may include multiple second periods corresponding to the terminal device 2, such as the second period b2. For an implementation form corresponding to the second period b2, please refer to the description of the second period b1.

For terminal device 3, if a request message c1 corresponding to terminal device 3 is received and the request message c1 belongs to a first type of request message, indication information c1 may be sent, where the indication information c1 indicates that the request of request message c1 is rejected, and timer c1 is started (the duration of timer c1 is the duration of second period c1). If a request message c2 corresponding to terminal device 3 is received and the request message c2 belongs to the first type of request message, indication information c2 or indication information c3 may be sent, where the indication information c2 indicates that the request of request message c2 is prohibited, and the indication information c3 indicates that terminal device 3 is deregistered from the first network. Subsequently, if a request message (e.g., request message c3) corresponding to terminal device 3 is received during the second period c1, the request message may be discarded.

Optionally, if the first communication device transmits the indication information c2, the indication information c4 may be transmitted at the end of the second period c1. The indication information c4 indicates that the request in the request message c2 is permitted.

It will be understood that the first period may include multiple second periods corresponding to the terminal device 3, such as the second period c2. For an implementation form corresponding to the second period c2, please refer to the description of the second period c1.

(4) In this embodiment of the present application, the first communication device may collect statistics on information such as the handover success rate and reselection success rate of a terminal device within a specified period of time, so that operation and maintenance engineers can know the network service quality based on the information. A handover request message is used as an example. It is assumed that the first communication device receives handover request message 1, handover request message 2, ..., and handover request message q in one hour. The terminal devices corresponding to m handover request messages are successfully handed over to the target cell, where q and m are both integers and m is less than or equal to q. In this case, the first communication device may determine that the handover success rate in one hour is m/q. According to the communication method provided in this embodiment of the present application, the first communication device may reject or discard the abnormal message. Therefore, in a possible implementation, when collecting statistics on the handover success rate or reselection success rate, the first communication device may not consider the abnormal message in this embodiment of the present application, or may collect multiple abnormal messages separately. For example, the first communication device receives handover request message 1, handover request message 2, ..., and handover request message q in one hour. The terminal devices corresponding to m handover request messages are successfully handed over to the target cell, and k handover request messages are abnormal messages, where k is an integer and k is less than q. In this case, the first communication device can determine that the handover success rate in one hour is m/(q-k).

(5) In the above embodiment, for example, a scenario to which the present application is applicable is when the serving network of a terminal device is handed over from a first network to a second network. The present application may also be applicable to other possible scenarios, such as a scenario in which the serving AMF of a terminal device is handed over from AMF1 in a 5G network to AMF2 in the 5G network, or a scenario in which the serving MME of a terminal device is handed over from MME1 in a 4G network to MME2 in the 4G network.

In the above, the solutions provided in the embodiments of the present application have been described primarily in terms of interactions between different communication devices. It will be understood that, to implement the aforementioned functions, the communication device may include corresponding hardware structures and/or software modules for performing the functions. Those skilled in the art will readily understand that, in the embodiments of the present application, the example units and algorithm steps described with reference to the embodiments disclosed herein may be implemented by hardware or a combination of hardware and computer software. Whether the functions are performed by hardware or by hardware driven by computer software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be considered to go beyond the scope of the present application.

In an embodiment of the present application, the first communication device may be divided into functional units based on the above-described exemplary method. For example, the first communication device may be divided into functional units based on their corresponding functions, or two or more functions may be integrated into one unit. The integrated unit may be implemented in the form of hardware or a software functional unit.

When an integrated unit is used, FIG. 6 is a possible exemplary block diagram of an apparatus according to an embodiment of the present application. As shown in FIG. 6, apparatus 600 may include a processing unit 602 and a communication unit 603. Processing unit 602 is configured to control and manage operation of apparatus 600. Communication unit 603 is configured to support apparatus 600 in communicating with another device. Optionally, communication unit 603, also referred to as a transceiver unit, may include a receiving unit and/or a transmitting unit, which are configured to perform receiving and transmitting operations, respectively. Apparatus 600 may further include a storage unit 601 configured to store program code and/or data for apparatus 600.

Device 600 may be the first communication device in the above-described embodiment. Processing unit 602 may support device 600 in performing the operations of the first communication device in the above-described example method. Alternatively, processing unit 602 may primarily perform the internal operations of the first communication device in the example method, and communication unit 603 may support device 600 in communicating with another device.

For example, in one embodiment, the communication unit 603 is configured to receive a first request message from a second communication device during a first period, the first request message belonging to a first type of request message, and when the processing unit 602 determines that the number of the first type of request messages received during the first period is greater than a first threshold, send first indication information to the second communication device, the first indication information indicating a rejection of the request of the first request message. The first type of request message is used to request a handover of a serving network of the terminal device from a first network to a second network, and the first network and the second network are networks supporting different communication standards.

In a possible design, the step of handing over the serving network of the terminal device from the first network to the second network includes a step of handing over the serving cell of the terminal device from a cell of the first network to a cell of the second network, or a step of reselecting the camping cell of the terminal device from a cell of the first network to a cell of the second network.

In a possible design, the first type request message includes first information, which indicates that the terminal device is located within a first area; the first type request message includes second information, which indicates that the type of the terminal device is a first terminal type; or the first type request message includes the first information and the second information.

In a possible design, after receiving the first request message from the second communication device during the first period, the communication unit 603 is further configured to receive a second request message from the second communication device during the first period, the second request message belonging to a first type of request message. The processing unit 602 is further configured to discard the second request message. Alternatively, the communication unit 603 is further configured to send second instruction information to the second communication device or send third instruction information to the third communication device. The second instruction information indicates prohibiting a request for the second request message, and the third instruction information indicates deregistering the terminal device from the first network.

In a possible design, the second request message is received during a second period included in the first period, and the start of the second period is the time when the first instruction information is transmitted.

In a possible design, the second request message is the first request message of the first type received by the first communication device during the second period.

In a possible design, the communication unit 603 is further configured to send fourth instruction information to the second communication device at the end of the second period, the fourth instruction information indicating that the request for the second request message is granted.

In a possible design, the first network is a 4G network and the second network is a 5G network, or the second network is a 4G network and the first network is a 5G network.

It should be understood that the division into units within the device is merely a logical division of function. In actual implementation, all or some of the units may be integrated into a single physical entity, or may be physically separated. In addition, all of the units within the device may be implemented in a form in which the processing elements call software, or in a form in which some units are implemented in a form in which the processing elements call software, and some units are implemented in a form in which some units are implemented in a form in which the processing elements call software. For example, each unit may be a separately located processing element, or may be integrated into a chip of the device for implementation. Alternatively, each unit may be stored in memory in the form of a program that is called by the processing elements of the device to perform the unit's functions. In addition, all or some of the units may be integrated or implemented independently. The processing elements herein may be referred to as processors, and may be integrated circuits with signal processing capabilities. In implementation processes, the operations in the above-mentioned methods or the above-mentioned units may be implemented using hardware integrated logic circuits within the processor elements, or may be implemented in a form in which the processing elements call software.

In one example, a unit in any one of the aforementioned devices may be one or more integrated circuits configured to perform the aforementioned method, such as one or more application specific integrated circuits (ASICs), one or more microprocessors (digital signal processors, DSPs), one or more field programmable gate arrays (FPGAs), or a combination of at least two of these types of integrated circuits. In another example, when a unit in an apparatus may be implemented in a form in which the processing element schedules a program, the processing element may be a processor, such as a general-purpose central processing unit (CPU), or another processor capable of calling a program. In yet another example, the unit may be integrated and implemented in the form of a system-on-a-chip (SOC).

The aforementioned unit configured to receive is an interface circuit of the device and is configured to receive a signal from another device. For example, when the device is implemented in the form of a chip, the receiving unit is an interface circuit of the chip and configured to receive a signal from another chip or device. The aforementioned unit configured to transmit is an interface circuit of the device and is configured to transmit a signal to another device. For example, when the device is implemented in the form of a chip, the transmitting unit is an interface circuit of the chip and configured to transmit a signal to another chip or device.

Figure 7 is a schematic diagram of the structure of a device according to one embodiment of the present application. Device 700 may be the first communication device in the aforementioned embodiment and is configured to implement the functionality of the first communication device in the aforementioned embodiment.

As shown in FIG. 7, the device 700 may include a processor 701, a memory 702, and an interface circuit 703. The processor 701 may be configured to process communication protocols and communication data and control the device 700. The memory 702 is configured to store programs and data, and the processor 701 may execute the methods performed by the device 700 in the embodiments of the present application based on the programs. The interface circuit 703 may be used by the device 700 to communicate with another device; the communication may be wired or wireless, and the interface circuit may be, for example, a service-oriented communication interface.

Alternatively, the memory 702 may be externally connected to the device 700. In this case, the device 700 may include the interface circuit 703 and the processor 701. Alternatively, the interface circuit 703 may be externally connected to the device 700. In this case, the device 700 may include the memory 702 and the processor 701. When both the interface circuit 703 and the memory 702 are externally connected to the device 700, the device 700 may include the processor 701.

The device 700 shown in FIG. 7 can perform the processes associated with the device 700 in the aforementioned method embodiments. The operations and/or functions of the modules of the device 700 shown in FIG. 7 can be used separately to perform the corresponding procedures in the aforementioned method embodiments. For details, please refer to the descriptions of the aforementioned method embodiments. To avoid repetition, detailed descriptions will be omitted here as appropriate.

In the embodiments of this application, the terms "system" and "network" may be used interchangeably. The term "and/or" describes a relationship between related entities and indicates that three relationships may exist. For example, A and/or B may refer to the following cases: only A is present, both A and B are present, and only B is present, where A and B may be singular or plural. "At least one of the following items (moieties)" or similar expressions refers to any combination of these items, including any combination of singular or multiple items (moieties). For example, "at least one of A, B, and C" includes A, B, C, AB, AC, BC, or ABC. Additionally, unless otherwise specified, ordinal numbers such as "first" and "second" used in the embodiments of this application are used to distinguish between multiple entities and not to limit the order, chronology, priority, or importance of the multiple entities.

Those skilled in the art will appreciate that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of a hardware-only embodiment, a software-only embodiment, or an embodiment having a combination of software and hardware. The present application may also take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk memory, optical memory, etc.) containing computer-usable program code.

This application is described with reference to flowcharts and/or block diagrams of methods, devices (systems), and computer program products according to this application. Each procedure and/or block of the flowcharts and/or block diagrams, and combinations of procedures and/or blocks in the flowcharts and/or block diagrams, may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or any other programmable data processing device to generate a machine, whereby the instructions, executed by the processor of the computer or any other programmable data processing device, generate an apparatus for performing the specified functions in one or more processes of the flowcharts and/or one or more blocks of the block diagrams.

These computer program instructions may also be stored on a computer-readable medium that can instruct a computer or any other programmable data processing device to operate in a particular manner, such that the instructions stored on the computer-readable medium produce an article of manufacture that includes an instruction apparatus that performs a particular function in one or more processes in the flowcharts and/or one or more blocks in the block diagrams.

These computer program instructions may also be loaded into a computer or another programmable data processing device such that a sequence of operations and steps are performed on the computer or another programmable device, thereby creating a computer-implemented process. Thus, the instructions executed on the computer or another programmable device provide steps for implementing particular functions within one or more processes in the flowcharts and/or one or more blocks in the block diagrams.

It is apparent that those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. This application is intended to cover these modifications and variations of this application as long as they fall within the scope of protection defined by the appended claims and their equivalents.

600, 700 devices
601 Memory Unit
602 Processing Unit
603 Communication Unit
701 processor
702 memory
703 Interface Circuit

Claims (14)

1. A communication method, the method being applicable to a first communication device, the method comprising:
receiving a first request message from a second communication device during a first time period, the first request message belonging to a first type of request message;
sending first indication information to the second communication device when the number of first type request messages received in the first period is greater than a first threshold, the first indication information indicating that the request of the first request message is to be rejected;
Including,
the first type request message is used to request a handover of a serving network of a terminal device from a first network to a second network, the first network and the second network being networks supporting different communication standards;
After the step of receiving a first request message from a second communication device during a first period of time, the method further comprises:
receiving a second request message from the second communication device during the first period, the second request message belonging to the first type of request message;
discarding the second request message, sending second instruction information to the second communication device, or sending third instruction information to a third communication device;
further comprising
The second instruction information indicates prohibiting a request for the second request message, and the third instruction information indicates deregistering the terminal device from the first network.
method. Handing over a serving network of a terminal device from a first network to a second network includes:
2. The method of claim 1, comprising: handing over a serving cell of the terminal device from a cell of the first network to a cell of the second network; or reselecting a camping cell of the terminal device from a cell of the first network to a cell of the second network. the first type request message includes first information, the first information indicating that the terminal device is located within a first area;
3. The method according to claim 1, wherein the first type request message includes second information, and the second information indicates that the type of the terminal device is a first terminal type; or the first type request message includes the first information and the second information. the second request message is received during a second period included in the first period;
The method according to claim 1 or 2 , wherein the start time of the second period is the time when the first instruction information is transmitted. The method of claim 4 , wherein the second request message is a first request message of a first type received by the first communication device during the second period. The method comprises:
5. The method of claim 4, further comprising: sending fourth indication information to the second communication device at an end of the second period, the fourth indication information indicating that the request in the second request message is granted. The method of claim 1 or 2, wherein the first network is a fourth-generation (4G) network and the second network is a 5G network, or the second network is a 4G network and the first network is a fifth-generation (5G) network. A communication device, the communication device comprising: a communication unit and a processing unit;
the communication unit is configured to receive a first request message from a second communication device during a first period, the first request message belonging to a first type of request message; and the communication unit is configured to send first indication information to the second communication device when the processing unit determines that a number of the first type of request messages received during the first period is greater than a first threshold, the first indication information indicating that the request of the first request message is rejected;
the first type request message is used to request a handover of a serving network of a terminal device from a first network to a second network, the first network and the second network being networks supporting different communication standards;
the communication unit is further configured to receive a second request message from the second communication device during the first period after receiving the first request message from the second communication device during the first period, wherein the second request message belongs to the first type of request message;
the processing unit is further configured to discard the second request message, or the communication unit is further configured to send second instruction information to the second communication device, or send third instruction information to a third communication device;
The second instruction information indicates prohibiting a request for the second request message, and the third instruction information indicates deregistering the terminal device from the first network.
Communication equipment. Handing over a serving network of a terminal device from a first network to a second network includes:
9. The communication device of claim 8, further comprising: handing over a serving cell of the terminal device from a cell of the first network to a cell of the second network; or reselecting a camping cell of the terminal device from a cell of the first network to a cell of the second network . the first type request message includes first information, the first information indicating that the terminal device is located within a first area;
10. The communication device according to claim 8 or 9, wherein the first type request message includes second information, and the second information indicates that the type of the terminal device is a first terminal type; or the first type request message includes the first information and the second information. the second request message is received during a second period included in the first period;
10. The communication device according to claim 8 , wherein the start point of the second period is a point in time when the first instruction information is transmitted. 12. The communication device of claim 11 , wherein the second request message is a first request message of a first type received by the communication device during the second period. The communication unit
12. The communication device of claim 11, further configured to send fourth instruction information to the second communication device at the end of the second period, the fourth instruction information indicating that the request in the second request message is granted. 10. The communication device according to claim 8, wherein the first network is a 4G network and the second network is a 5G network, or the second network is a 4G network and the first network is a 5G network.