Communication method and device

Abstract

The invention provides a communication method and device, relates to the technical field of wireless communication, and is used for solving the problem that a message cannot be accurately transmitted to edge servers due to IP address conflict of two edge servers. The method comprises: an EASDF receiving a first request message sent by a terminal device, the first request message being used for querying an IP address of a first edge server; and under the condition that the first IP address of the first edge server queried from the DNS server is the same as the second IP address of a second edge server currently accessed by the terminal device, a first response message is sent to the terminal device, the first response message comprises a third IP address of the first edge server, and the third IP address is different from the second IP address.

Description

Technical Field

[0001] The present application relates to the field of wireless communications, and in particular to a communication method and device. Background Art

[0002] Multi-access edge computing (MEC) technology migrates computing storage capabilities and business service capabilities to the edge of the network, so as to avoid having to transmit data back to the cloud as much as possible, reducing the waiting time and network costs of data going back and forth between the cloud and the cloud. Therefore, MEC technology can provide users with low-latency, high-bandwidth services.

[0003] For a terminal device to use edge applications, it must first obtain the Internet protocol (IP) address of the edge application server (EAS) through a service discovery mechanism based on the domain name system (DNS). Currently, the IP addresses of edge application servers (EAS) under different data network access identifiers (DNAI) are allocated by the corresponding MEC platform. In actual situations, different MEC platforms may allocate the same LAN IP address to different EAS. For example, Figure 1 As shown in the figure, the IP address assigned by MEC platform A to EAS1 is 1.1.1.1, and the IP address assigned by MEC platform B to EAS2 is also 1.1.1.1. In this way, when the terminal device simultaneously accesses different EASs under two DNAIs through a session, if the LAN IP addresses of the two EASs are the same, the messages of the terminal device cannot be accurately transmitted to the corresponding EAS. Summary of the invention

[0004] The present application provides a communication method and device for solving the problem that messages cannot be accurately transmitted due to IP address conflicts between two edge servers.

[0005] In order to achieve the above purpose, the embodiment of the present application adopts the following technical solution:

[0006] In a first aspect, a communication method is provided, which is applied to an edge application server discovery function (EASDF), the method comprising: receiving a first request message sent by a terminal device, the first request message being used to query an IP address of a first edge server; the IP address of the first edge server queried from a first DNS server being a first IP address; and sending a first response message to the terminal device when the first IP address of the first edge server is the same as a second IP address of a second edge server currently accessed by the terminal device, the first response message comprising a third IP address of the first edge server, the third IP address being different from the second IP address.

[0007] Based on the method provided in the first aspect, when the first IP address of the first edge server and the second IP address of the second edge server are the same, EASDF can feed back a first response message including a third IP address to the terminal device, so that in the subsequent message transmission process between the terminal device and the first edge server and the second edge server, the message can be forwarded based on the different IP addresses of the two edge servers, thereby ensuring accurate transmission of the message.

[0008] In a possible implementation, the third IP address is a local area network IP address newly allocated to the first edge server.

[0009] Based on the above implementation, when the third IP address is a local area network IP address, the terminal can access the first edge server through the edge path.

[0010] In one possible implementation, the method also includes: sending a second request message to a session management function (SMF), the second request message including a third IP address and a first IP address, the second request message being used to trigger the SMF to establish a transmission channel between the first edge server and the terminal device based on the third IP address and the first IP address; and receiving a second response message sent by the SMF to respond to the second request message.

[0011] Based on the above implementation, the SMF may be triggered to establish a transmission channel between the first edge server and the terminal device, so that the first edge server and the terminal device can communicate based on the established transmission channel.

[0012] In a possible implementation, the method further includes: establishing a correspondence between a fully qualified domain name (FQDN) of the first edge server and the third IP address.

[0013] Based on the above implementation, by establishing a correspondence between the FQDN of the first edge server and the third IP address, it is clear that the third IP address is allocated to the first edge server for use, thereby avoiding repeated allocation of the third IP address to other edge servers.

[0014] In a possible implementation, the method further includes: receiving a third request message sent by the SMF, the third request message being used to request deletion of the correspondence between the FQDN of the first edge server and the third IP address; and deleting the correspondence between the FQDN of the first edge server and the third IP address based on the third request message.

[0015] Based on the above implementation, by deleting the correspondence between the FQDN of the first edge server and the third IP address, the third IP address can be recycled, so that the third IP address can be allocated to other edge servers in need in the subsequent process. It should be understood that recycling IP addresses is conducive to alleviating the pressure on the network's demand for IP address resources.

[0016] In a possible implementation, the method further includes: sending a third response message to the SMF, where the third response message is used to indicate a deletion result of the correspondence between the FQDN of the first edge server and the third IP address.

[0017] Based on the above implementation, by sending a third response message to SMF, SMF can be informed of the deletion result of the corresponding relationship, which is conducive to SMF correctly treating the third IP address (that is, whether the third IP address is still considered to be the IP address of the first edge server).

[0018] In a possible implementation, the third IP address is a public IP address of the first edge server, or the third IP address is a public IP address of another public server that provides the same service as the first edge server.

[0019] Based on the above implementation, when the third IP address is a public IP address, the terminal can access the first edge server or other public network servers that provide the same service as the first server through a public network path.

[0020] In a possible implementation, the method also includes: sending a fourth request message to the second DNS server, the fourth request message is used to query the public IP address of the first edge server; receiving a fourth response message from the second DNS server, the fourth response message is used to indicate that the public IP address of the first edge server is the third IP address.

[0021] It should be understood that the above implementation provides an implementation method for obtaining the public IP address of the first edge server, and the present application is not limited thereto.

[0022] According to a second aspect, a communication method is provided, which is applied to a unified data repository (UDR), the method comprising: receiving a fifth request message, the fifth request message being used to request information of a registered edge server, the information of the edge server comprising an IP address of the edge server; and when it is identified that the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs, sending a fifth response message indicating that registration has failed.

[0023] Based on the method provided in the second aspect, the UDR can refuse to register an edge server that has an IP address conflict with other edge servers during the service registration process, so that the terminal will not find two edge servers with the same IP address during the service discovery process. That is, based on the method provided in the second aspect, the IP addresses of the edge servers discovered by the terminal during the service discovery process are all different, and the terminal can correctly access the corresponding edge server based on the different IP addresses of different edge servers.

[0024] In a possible implementation, the fifth response message includes a failure reason, where the failure reason is used to indicate that the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs.

[0025] Based on the above implementation, the edge server can be informed that the reason for the failure of service registration is the IP address conflict, so that the edge server can re-register after changing the IP address to increase the probability of successful registration.

[0026] In a possible implementation manner, receiving the fifth request message includes: receiving, by the NEF, the fifth request message sent by the AF; and sending the fifth response message includes: sending, by the NEF, the fifth response message to the AF.

[0027] Based on the above implementation, an example of a specific transmission path of the fifth request message and the fifth response message is given.

[0028] According to a third aspect, a communication method is provided, which is applied to SMF, and the method includes: receiving a sixth request message, the fifth request message is used to trigger the ULCL insertion process, and the sixth request message includes a first IP address of a first edge server; when the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, a third IP address is configured for the first edge server, and the ULCL insertion process is performed based on the third IP address and the first IP address.

[0029] Based on the method provided by the third aspect, in the event of a conflict between the IP addresses of the two edge servers, the SMF can allocate a new IP address (i.e., a third IP address) to the first edge server, and perform a ULCL insertion process based on the third IP address and the first IP address, thereby enabling subsequent message transmission between the terminal device and the first edge server and the second edge server to be performed based on the different IP addresses of the two edge servers, thereby ensuring accurate transmission of the message.

[0030] In a possible implementation, the ULCL insertion process is performed based on the third IP address and the first IP address, including: sending a seventh request message to the L-PSA, the seventh request message including a network address translation (NAT) policy, and the NAT policy is used to convert the address of the message between the first IP address and the third IP address.

[0031] Based on the above implementation, the message transmission based on the third IP address and the first IP address between the terminal device and the first edge server is implemented by configuring the NAT policy.

[0032] In one possible implementation, the NAT policy includes a first policy and a second policy, the first policy is used to change the destination address of the first message from the third IP address to the first IP address, and the second policy is used to change the source address of the second message from the first IP address to the third IP address.

[0033] Based on the above implementation, the first strategy can be used to enable the first edge server to know that it is the receiving end of the first message after receiving the modified first message, and the second strategy can be used to enable the terminal device to know that the sending end of the second message is the first edge server after receiving the modified second message. In this way, message transmission based on the third IP address and the first IP address can be implemented between the terminal device and the first edge server.

[0034] In a possible implementation, the NAT policy further includes an aging time.

[0035] Based on the above implementation, the aging mechanism of the NAT policy is utilized by configuring the aging time to reclaim the third IP address, thereby alleviating the pressure on the demand for IP address resources.

[0036] In a possible implementation manner, the method further includes: sending a sixth response message, where the sixth response message is used to indicate a result of the ULCL insertion process.

[0037] Based on the above implementation manner, by feeding back the sixth response information, the corresponding network element can learn the result of the ULCL insertion process.

[0038] In a possible implementation, when the ULCL insertion process is successful, the sixth response message includes the third IP address.

[0039] Based on the above implementation, the sixth response message includes the third IP address, so that the corresponding network element can learn that the first edge server is newly allocated a third IP address, so as to correctly treat the message related to the third IP address.

[0040] In a fourth aspect, a communication device is provided for implementing the above method. The communication device may be the EASDF in the above first aspect, or a device including the above EASDF, or a module in the EASDF in the above first aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the EASDF functions; or, the communication device may be the UDR in the above second aspect, or a device including the above UDR, or a module in the UDR in the above second aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the UDR functions; or, the communication device may be the SMF in the above third aspect, or a device including the above SMF, or a module in the SMF network element in the above third aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the SMF functions.

[0041] In a possible implementation, the communication device may include a processing module. The processing module, which may also be referred to as a processing unit, may be used to implement the processing functions in any of the above aspects and any possible implementations thereof. The processing module may be, for example, a processor.

[0042] In a possible implementation, the communication device may further include an interface module. The interface module, which may also be referred to as an interface unit, is used to implement the sending and / or receiving functions in any of the above aspects and any possible implementations thereof. The interface module may be composed of an interface circuit, a transceiver, a transceiver or a communication interface.

[0043] In a possible implementation, the interface module includes a sending module and a receiving module, which are respectively used to implement the sending and receiving functions in any of the above aspects and any possible implementations thereof.

[0044] In a fifth aspect, a communication device is provided, comprising: a processor; the processor is used to couple with a memory, and after reading the instruction in the memory, execute the method as described in any of the above aspects according to the instruction. The communication device can be the EASDF in the above first aspect, or a device including the above EASDF, or a module in the EASDF in the above first aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement part or all of the EASDF functions; or, the communication device can be the UDR in the above second aspect, or a device including the above UDR, or a module in the UDR in the above second aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement part or all of the UDR functions; or, the communication device can be the SMF in the above third aspect, or a device including the above SMF, or a module in the SMF network element in the above third aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement part or all of the SMF functions. In a possible implementation, the communication device also includes a memory, which is used to store necessary program instructions and data.

[0045] In a possible implementation, the communication device is a chip or a chip system. Optionally, when the communication device is a chip system, it can be composed of a chip, or it can include a chip and other discrete devices.

[0046] In a sixth aspect, a communication device is provided, comprising: a processor and an interface circuit; the interface circuit is used to receive a computer program or instruction and transmit it to the processor; the processor is used to execute the computer program or instruction so that the communication device performs the method as described in any of the above aspects. The communication device can be the EASDF in the above first aspect, or a device including the above EASDF, or a module in the EASDF in the above first aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the EASDF functions; or, the communication device can be the UDR in the above second aspect, or a device including the above UDR, or a module in the UDR in the above second aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the UDR functions; or, the communication device can be the SMF in the above third aspect, or a device including the above SMF, or a module in the SMF network element in the above third aspect, such as a chip, a chip system or a circuit, or a logical node, a logical module or a software implementation that can implement some or all of the SMF functions.

[0047] In a possible implementation, the communication device is a chip or a chip system. Optionally, when the communication device is a chip system, it can be composed of a chip, or it can include a chip and other discrete devices.

[0048] In a seventh aspect, a computer-readable storage medium is provided, wherein instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is run on a computer, the computer can execute the method described in any one of the above aspects.

[0049] In an eighth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, enables the computer to execute the method described in any one of the above aspects.

[0050] Among them, the technical effects brought about by any possible implementation method in the fourth to eighth aspects can refer to the technical effects brought about by any aspect in the first to third aspects or different possible implementation methods in any aspect, and will not be repeated here.

[0051] It can be understood that, under the premise that the solutions are not contradictory, the solutions in each aspect can be combined. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 A schematic diagram of a scenario of IP address conflict provided in an embodiment of the present application;

[0053] Figure 2 A flow chart of a service registration provided for related technologies;

[0054] Figure 3 A flow chart of service discovery for related technologies;

[0055] Figure 4 A flowchart of a ULCL insertion process provided for related technology;

[0056] Figure 5 An architecture diagram of a communication system provided in an embodiment of the present application;

[0057] Figure 6 A schematic diagram of the hardware structure of a communication device provided in an embodiment of the present application;

[0058] Figure 7 A flow chart of a communication method provided in an embodiment of the present application;

[0059] Figure 8 A flowchart of another communication method provided in an embodiment of the present application;

[0060] Fig. 9 A flowchart of another communication method provided in an embodiment of the present application;

[0061] Fig.10 A flowchart of another communication method provided in an embodiment of the present application;

[0062] Fig.11 A flowchart of another communication method provided in an embodiment of the present application;

[0063] Fig.12 A flowchart of another communication method provided in an embodiment of the present application;

[0064] Fig.13 A flowchart of another communication method provided in an embodiment of the present application;

[0065] Fig.14 A flowchart of another communication method provided in an embodiment of the present application;

[0066] Fig.15 A schematic diagram of the structure of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] Before introducing the technical solution of the present application, the relevant technical terms involved in the present application are explained. It is understandable that these explanations are intended to make the present application easier to understand and should not be regarded as limiting the scope of protection claimed by the present application.

[0068] 1. Service Registration

[0069] The edge server can register the service with the UDR so that the core network element can know the information of the edge server. In this way, in the subsequent process, the core network element can use the edge server based on the information of the edge server.

[0070] For example, Figure 2 A flowchart of a service registration provided by the related technology is shown. Figure 2 As shown, service registration includes the following steps:

[0071] S101. AF sends a Nef_EASDdeployment_Create_Request message carrying edge server information to NEF. The edge server information may include the FQDN, DNAI, and L-DNS IP address of the edge server.

[0072] S102. NEF sends a Nudr_DM_Create_Request message carrying information of the edge server to UDR.

[0073] After receiving the Nudr_DM_Create_Request message, the UDR may record the edge server information.

[0074] S103. The UDR sends a Nudr_DM_Create_Response message carrying a success flag to the NEF.

[0075] It should be understood that the Nudr_DM_Create_Response message carries a success flag, indicating that the service registration is successful.

[0076] S104. NEF sends a Nef_EASDdeployment_Create_Response message carrying a success flag to AF.

[0077] 2. Service Discovery

[0078] In a 5G network, if a terminal device wants to use edge services, it must first obtain the IP address of the edge server through a DNS-based service discovery mechanism. For example, Figure 3 FIG. 1 is a flowchart showing a service discovery process in the related art. Figure 3 As shown, service discovery can include the following steps:

[0079] S201. The terminal device sends a PDU session establishment request to the SMF.

[0080] S202. SMF selects EASDF network element.

[0081] S203. SMF sends a Neasdf_DNSContext_Create Request to EASDF.

[0082] S204. EASDF returns Neasdf_DNSContext_Create Response to SMF.

[0083] S205. If the EAS information is updated, the SMF sends a Neasdf_DNSContext_UpdateRequest to the EASDF.

[0084] S206. EASDF returns Neasdf_DNSContext_Update Response to SMF.

[0085] S207: The terminal device sends a DNS Query message to the EASDF.

[0086] S208. After receiving the DNS Query message, EASDF sends a Neasdf_DNSContext_NotifyRequest to SMF.

[0087] S209. SMF returns Neasdf_DNSContext_Notify Response to EASDF.

[0088] S210. SMF sends Neasdf_DNSContext_Update Request to EASDF to provide configuration information (ECS option) for the DNSQuery.

[0089] S211. EASDF returns Neasdf_DNSContext_Update Response to SMF.

[0090] S212. EASDF adds the ECS option to the DNS Query message and sends the DNS Query message to the DNS server to complete the DNS query request.

[0091] S213. The DNS server returns a DNS Response to the EASDF.

[0092] S214. After receiving the DNS Response message, EASDF sends a Neasdf_DNSContext_Notify Request to SMF to report the received DNS Response message to SMF.

[0093] S215. SMF returns Neasdf_DNSContext_Notify Response to EASDF.

[0094] S216. SMF inserts ULCL / BP according to the relevant information (EAS IP address) of the DNS Response message provided by EASDF, and completes the establishment of the data plane path for the terminal device.

[0095] S217. After completing the establishment of the data plane path for the terminal device, SMF sends a Neasdf_DNSContext_Update Request to EASDF.

[0096] S218. After receiving the notification, EASDF returns Neasdf_DNSContext_Update Response to SMF.

[0097] S219. EASDF sends the DNS Response message to the terminal device.

[0098] 3. Uplink classifier (ULCL)

[0099] 3GPP defines the ULCL function for data diversion on the 5G user plane. ULCL is a processing node that diverts uplink service data and aggregates the diverted downlink data. UPF has two forms: UPF PDU Session Anchor (PSA UPF) and UPF Uplink Classifier (ULCL UPF). SMF can insert ULCL UPF when or after the PDU session is established, according to its own configured rules or instructions from other network elements. SMF can insert multiple ULCL UPFs for one PDU session.

[0100] For example, Figure 4 FIG. 1 is a flow chart showing a ULCL insertion-related process in the related art. Figure 4 As shown, the ULCL insertion-related process includes the following steps:

[0101] S301. The terminal device is successfully registered and a PDU session is created.

[0102] S302. AF / EAS sends a ULCL insertion request message to NEF. The ULCL insertion request message carries the DNAI, IP address and APP identifier of the edge server.

[0103] S303. NEF sends a ULCL insertion request message to PCF.

[0104] S304. PCF sends a ULCL insertion request message to SMF.

[0105] S305. SMF selects L-PSA according to DNAI.

[0106] S306. The SMF sends a session creation / modification request message to the L-PSA. The session creation / modification request message includes the ULCL policy.

[0107] S307. SMF sends a ULCL insertion success message to PCF.

[0108] S308. The PCF sends a ULCL insertion success message to the NEF.

[0109] S309. NEF sends a ULCL insertion success message to AF / EAS.

[0110] The method provided in the present application can be used in various communication systems. For example, the communication system can be a universal mobile telecommunications system (UMTS) system, a long term evolution (LTE) system, a fifth generation (5G) communication system, a communication system to be evolved (such as a sixth generation (6G) communication system, etc.), or a system integrating multiple systems, etc., without limitation. Among them, 5G can also be called new radio (NR). The following is Figure 5 The method provided in the present application is described by taking the communication system 10 as an example. Figure 5 It is only a schematic diagram and does not constitute a limitation on the applicable scenarios of the technical solution provided in this application.

[0111] like Figure 5 As shown, the communication system 10 may include a core network, one or more access points (AN) communicating with the core network, and at least one terminal device communicating with the access point.

[0112] exist Figure 5 In the , access point is used to connect the terminal device to the core network. It can be understood that the access point can use different access technologies to connect the terminal device to the core network. For different access technologies, the specific form of the access point is different, and the connection method between the access point and the core network is also different. For example, the access point can connect the terminal device to the core network through the wireless access technology defined by the 3GPP standard group. In this scenario, the access point is a radio access network (RAN) node. For another example, the access point can connect the terminal device to the core network through a non-3GPP access technology. In this scenario, the access point is a non-3GPP interworking function (N3IWF) network element, a trusted non-3GPP gateway function (TNGF) network element, or a wired access gateway function (W-AGF) network element, etc.

[0113] In this application, the wireless access technology defined by the 3GPP standard group includes but is not limited to: 2G access technology, 3G access technology, 4G access technology, 5G access technology or future evolved 3GPP access technology (such as 6G access technology). Non-3GPP access technology can be understood as communication technology other than 3GPP access technology, including but not limited to: wireless local area network (WLAN) access technology, trusted WAN access technology, untrusted WAN access technology, wired access technology, fixed network access technology or home network access technology. It can be understood that WLAN access technology corresponds to WLAN access points (AP) deployed in the park, or WLAN AP hotspots deployed in public places, and wired access technology corresponds to wired communication deployed in the home network. The above-mentioned trusted WAN access technology can also be called trusted non-3GPP access technology, and the above-mentioned untrusted WAN access technology can also be called untrusted non-3GPP access technology.

[0114] For example, Figure 5 As shown, the core network may include one or more core network elements, such as UPF network elements, SMF network elements, AMF network elements, network exposure function (NEF) network elements, policy control function (PCF) network elements, application function (AF) network elements, etc. The core network may also include other network elements, which are not listed here. It can be understood that in this example, the core network is a 5G core network (5Gcore, 5GC).

[0115] Understandably, in Figure 5 In the 5G network, the terminal device can access the 5G network through the (R)AN, and the terminal device communicates with the AMF network element through the N1 interface (referred to as N1); the (R)AN communicates with the AMF network element through the N2 interface (referred to as N2); the (R)AN communicates with the UPF network element through the N3 interface (referred to as N3); the SMF network element communicates with the UPF network element through the N4 interface (referred to as N4); the UPF network element accesses the data network (data network, DN) through the N6 interface (referred to as N6). In addition, Figure 5The control plane network elements shown, such as the AMF network element, SMF network element, NEF network element, PCF network element, or AF network element, can interact using service-based interfaces. For example, the service-based interface provided by the AMF network element to the outside may be Namf; the service-based interface provided by the SMF network element to the outside may be Nsmf; the service-based interface provided by the NEF network element to the outside may be Nnef; the service-based interface provided by the PCF network element to the outside may be Npcf; and the service-based interface provided by the AF network element to the outside may be Naf.

[0116] The above exemplary introductions are given to the communication systems and network architectures to which the method provided by the present application can be applied. It should be understood that, in specific applications, the communication systems or network architectures to which the method provided by the present application can be applied are not limited to the above examples. In order to better understand the method provided by the present application, the nodes, devices or network elements involved in the above communication systems and network architectures are introduced below.

[0117] The access point in the present application may be a device for communicating with a terminal device, for example, it may include an evolved base station (NodeB or eNB or e-NodeB, evolutional Node B) in a long term evolution (LTE) system or an enhanced LTE (LTE-advanced, LTE-A) system, such as a traditional macro base station eNB and a micro base station eNB in ​​a heterogeneous network scenario. Alternatively, it may include a next generation node B (next generation node B, gNB) in an NR system. Alternatively, it may include a transmission reception point (TRP), a home base station (e.g., home evolved NodeB, or home Node B, HNB), a base band unit (BBU), a base band pool (BBUpool), or a wireless fidelity (WiFi) access point (access point, AP), etc. Alternatively, it may include a base station in a non-terrestrial network (NTN), that is, it may be deployed on a flying platform or a satellite. In the NTN, the network device or access device may be used as a layer 1 (L1) relay, or as a base station, or as an integrated access and backhaul (IAB) node. Alternatively, the network device may be a device that implements the base station function in IoT, such as a device that implements the base station function in drone communications, V2X, D2D, or machine to machine (M2M).

[0118] In some possible scenarios, the access point may also be a module or unit that can implement some functions of the base station, for example, the access point may be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU may be set separately, or may be included in the same network element, such as a baseband unit (BBU). The RU may be included in a radio frequency device or radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0119] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, the network device or access device may be a network device or a module of a network device in an open radio access network (open RAN, ORAN) system. In the ORAN system, CU may also be referred to as open (open, O)-CU, DU may also be referred to as O-DU, CU-CP may also be referred to as O-CU-CP, CU-UP may also be referred to as O-CU-UP, and RU may also be referred to as O-RU. Any of the CU (or CU-CP, CU-UP), DU and RU in this application may be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0120] Optionally, the base station in the embodiment of the present application may include various forms of base stations, such as: macro base stations, micro base stations (also called small stations), relay stations, access points, home base stations, TRPs, transmitting points (TP), mobile switching centers, etc., and the embodiments of the present application do not specifically limit this.

[0121] In the embodiments of the present application, the form of the access point is not limited, and the device for implementing the function of the access point may be a network device or an access device; or it may be a device that can support the access point to implement the function, such as a chip system. The device may be installed in the access point or used in conjunction with the access point.

[0122] The terminal equipment involved in the present application can be a user equipment (UE), an access terminal, a terminal unit, a user station, a terminal station, a mobile station, a mobile station, a mobile station, a remote station, a remote terminal, a user terminal terminal equipment, a mobile device, a wireless communication device, a terminal agent, a tablet computer (pad), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a vehicle-mounted transceiver unit, a wearable device, or a terminal device. The access terminal can be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a drone, a robot, a smart point of sale (point of The terminal may be a point-of-sale (POS) machine, a customer-premises equipment (CPE) or a wearable device, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. Alternatively, the terminal may be a terminal with a communication function in the Internet of Things (IoT), such as a terminal in V2X (such as a vehicle networking device), a terminal in D2D communication, or a terminal in M2M communication, etc. The terminal may be mobile or fixed.

[0123] The embodiments of the present application do not limit the device form of the terminal device. The device for realizing the function of the terminal device can be the terminal device; it can also be a device that can support the terminal device to realize the function, such as a chip system. The device can be installed in the terminal device or used in combination with the terminal device. In the embodiments of the present application, the chip system can be composed of chips, or it can include chips and other discrete devices.

[0124] In this application, the core network is mainly responsible for maintaining the subscription data of the mobile network and providing functions such as session management, mobility management, policy management and security authentication for terminal devices. The core network includes UPF network elements and control plane function (CPF) network elements.

[0125] Optionally, the UPF network element is mainly responsible for user data processing (such as at least one of forwarding, receiving, quality of service (QoS) control or billing information statistics). For example, the UPF network element can receive user data from the DN, and forward the user data to the terminal device through the RAN node or access network element. The UPF network element can also receive user data from the terminal device through the RAN node or access network element, and forward the user data to the DN. DN can provide data transmission services for users. For example, it can provide mobile operator services, Internet services or third-party services.

[0126] Optionally, UPF has two forms: UPF PDU Session Anchor (PSA UPF) and UPF Uplink Classifier (ULCL UPF). Among them, PSA UPF is divided into PSA1 UPF and PSA2 UPF. PSA1 UPF is the UPF that allocates user plane IP to UE when UE is activated. It is also the session anchor point for UE to access the Internet, called the primary anchor point UPF; PSA2 UPF is the PDU session anchor point when UE accesses the local network, also called the secondary anchor point UPF. In some of the following embodiments, for the convenience of description, PSA1 UPF may be referred to as PSA, PSA2 UPF may be referred to as local PSA (local-PSA, L-PSA), and ULCL UPF may be referred to as ULCL.

[0127] CPF network elements are mainly responsible for user registration and authentication, mobility management, and sending packet forwarding strategies and QoS control strategies to the user plane (such as UPF). CPF network elements can include at least one of the following: AMF network element, SMF network element, NEF network element, PCF network element, AF network element or UDR network element. The functions of these network elements are introduced below.

[0128] Optionally, the AMF network element is mainly used for mobility management in mobile networks, such as user location update, user network registration, user switching, etc.

[0129] Optionally, the SMF network element is mainly used for session management in mobile networks, such as session establishment, modification, and release. Specific functions include allocating IP addresses to users, selecting UPFs that provide message forwarding functions, and sending data packet forwarding policies and QoS policies to UPF network elements based on the interface between the SMF network element and the UPF network element.

[0130] Optionally, the PCF network element mainly supports providing a unified policy framework to control network behavior, providing policy rules to the control layer network function, and is responsible for obtaining user subscription information related to policy decisions. The PCF network element can provide policies to the AMF network element and SMF network element, such as QoS policy, slice selection policy, etc.

[0131] Optionally, the NEF network element is mainly used to support the opening of capabilities and events.

[0132] Optionally, the AF network element mainly supports interaction with the core network to provide services, such as influencing data routing decisions, policy control functions, providing some third-party services to the network side, or sending application-related requirements to the PCF network element, so that the PCF network element generates corresponding policies.

[0133] Optionally, the UDR network element mainly supports the Unified Data Management (UDM) function to store and retrieve contract data, the PCF to store and retrieve contract data, and to store application data of the NEF.

[0134] For the convenience of description, the above network elements may have corresponding abbreviations, for example, the PCF network element may be abbreviated as PCF, which will not be repeated below.

[0135] Understandably, Figure 5 The communication system or network architecture shown is only used as an example and is not used to limit the technical solution of the present application. Those skilled in the art should understand that in the specific implementation process, the above communication system or the above network architecture may also include other devices, and the number of access points, terminal devices, AMF network elements, UPF network elements, AF network elements, SMF network elements, etc. may also be determined according to specific needs without limitation.

[0136] Optional, this application Figure 5 Each network element or device (such as access point, terminal device, AMF network element, UPF network element, AF network element, SMF network element, etc.) can also be called a communication device, which can be a general device or a special device. This application does not make specific limitations on this.

[0137] Optional, this application Figure 5 The relevant functions of each network element or device (such as access point, terminal device, AMF network element, UPF network element, AF network element, SMF network element, etc.) in the network can be implemented by one device, or by multiple devices together, or by one or more functional modules in one device, and this application does not make specific restrictions on this. It can be understood that the above functions can be network elements in hardware devices, or software functions running on dedicated hardware, or a combination of hardware and software, or virtualization functions instantiated on a platform (for example, a cloud platform).

[0138] In specific implementation, this application Figure 5 Each network element or device in (such as access point, terminal equipment, AMF network element, UPF network element, AF network element, SMF network element, etc.) can use Figure 6 The structure shown, or including Figure 6 Parts shown. Figure 6 The hardware structure diagram of the communication device applicable to the present application is shown. The communication device 20 includes at least one processor 201 and at least one communication interface 204, which are used to implement the method provided by the present application. The communication device 20 may also include a communication line 202 and a memory 203.

[0139] The processor 201 may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present application.

[0140] The communication link 202 may include a path to transmit information between the above-mentioned components, such as a bus.

[0141] The communication interface 204 is used to communicate with other devices or communication networks. The communication interface 204 can be any transceiver-like device, such as an Ethernet interface, a radio access network (RAN) interface, a wireless local area network (WLAN) interface, a transceiver, a pin, a bus, an interface circuit, or a transceiver circuit.

[0142] The memory 203 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory may exist independently and be coupled to the processor 201 via the communication line 202. The memory 203 may also be integrated with the processor 201. The memory provided in the present application may generally be non-volatile.

[0143] Among them, the memory 203 is used to store the computer execution instructions involved in executing the solution provided by this application, and the execution is controlled by the processor 201. The processor 201 is used to execute the computer execution instructions stored in the memory 203, so as to implement the method provided by this application. Alternatively, optionally, in this application, the processor 201 may also perform the processing-related functions in the method provided below in this application, and the communication interface 204 is responsible for communicating with other devices or communication networks, which is not specifically limited in this application.

[0144] Optionally, the computer-executable instructions in the present application may also be referred to as application code, which is not specifically limited in the present application.

[0145] The coupling in this application is an indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, and is used for information exchange between devices, units or modules.

[0146] As an embodiment, the processor 201 may include one or more CPUs, such as Figure 6 CPU0 and CPU1 in.

[0147] As an embodiment, the communication device 20 may include multiple processors, such as Figure 6201 and processor 207 in the embodiment of the present invention. Each of these processors may be a single-CPU processor or a multi-CPU processor. The processor herein may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0148] As an embodiment, the communication device 20 may further include an output device 205 and / or an input device 206. The output device 205 is coupled to the processor 201 and can display information in a variety of ways. For example, the output device 205 may be a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector. The input device 206 is coupled to the processor 201 and can receive user input in a variety of ways. For example, the input device 206 may be a mouse, a keyboard, a touch screen device, or a sensor device.

[0149] Understandably, Figure 6 The structure shown in the figure does not constitute a limitation on the communication device, except Figure 6 In addition to the components shown, the communication device may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0150] It can be understood that the message names between the various communication entities or the names of the parameters in the messages in the following embodiments of the present application are only examples, and other names may be used in specific implementations, and the present application does not make any specific limitations on this.

[0151] It can be understood that in this application, "sending information to... (such as a communication entity)" can be understood as the destination end of the information being the communication entity. It can include sending information to the communication entity directly or indirectly. "Receiving information from... (such as a communication entity)" can be understood as the source end of the information being the communication entity, which can include receiving information from the communication entity directly or indirectly. The information may be processed as necessary between the source end and the destination end of the information transmission, such as format changes, etc., but the destination end can understand the valid information from the source end. Similar expressions in this application can be understood similarly and will not be repeated here.

[0152] It is understandable that in the present application, " / " can indicate that the objects associated with each other are in an "or" relationship, for example, A / B can indicate A or B; "and / or" can be used to describe that there are three relationships between the associated objects, for example, A and / or B can indicate: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In addition, expressions similar to "at least one of A, B and C" or "at least one of A, B or C" are usually used to indicate any of the following: A exists alone; B exists alone; C exists alone; A and B exist at the same time; A and C exist at the same time; B and C exist at the same time; A, B and C exist at the same time. The above uses A, B and C as an example to illustrate the optional items of the item. When there are more elements in the expression, the meaning of the expression can be obtained according to the above rules.

[0153] In order to facilitate the description of the technical solution of the present application, in the present application, words such as "first" and "second" may be used to distinguish between technical features with the same or similar functions. The words such as "first" and "second" do not limit the quantity and execution order, and the words such as "first" and "second" do not necessarily limit them to be different. In the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations, and any embodiment or design described as "exemplary" or "for example" should not be interpreted as being more preferred or more advantageous than other embodiments or designs. The use of words such as "exemplary" or "for example" is intended to present related concepts in a concrete way for easy understanding.

[0154] It is understood that the "embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, the various embodiments in the entire specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It is understood that in various embodiments of the present application, the size of the sequence number of each process does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the present application.

[0155] It can be understood that in the present application, "when...", "in the case of...", "if" and "if" all mean that corresponding processing will be taken under certain objective circumstances, but do not limit the time, nor do they require any judgment action when implementing them, nor do they mean the existence of other limitations.

[0156] The term “simultaneously” in the present application may be understood as at the same time point, within a period of time, or within the same cycle.

[0157] In this application, unless otherwise specified, "multiple" can be understood as two or more than two. For example, multiple terminal devices can be understood as two or more than two terminal devices.

[0158] It is understandable that some optional features in this application may be implemented independently in some scenarios without relying on other features, such as the solution on which it is currently based, to solve corresponding technical problems and achieve corresponding effects. They may also be combined with other features according to needs in some scenarios. Accordingly, the device provided in this application may also realize these features or functions accordingly, which will not be elaborated here.

[0159] It can be understood that the same step or steps or technical features with the same functions in different embodiments of the present application can be referenced to each other.

[0160] like Figure 7 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0161] S401. EASDF receives a first request message from a terminal device, where the first request message is used to query an IP address of a first edge server.

[0162] Optionally, the first request message may include the FQDN of the first edge server, which is not limited.

[0163] In the embodiment of the present application, the edge server may be an EAS, or other types of servers in the MEC network.

[0164] S402: The IP address of the first edge server obtained by the EASDF from the first DNS server is the first IP address.

[0165] As a possible implementation manner, the EASDF may select a first DNS service based on the DNS processing rule and the FQDN of the first edge server, and use the IP address of the first edge server queried from the first DNS server as the first IP address.

[0166] S403: When the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, the ESADF sends a first response message to the terminal device, wherein the first response message includes the third IP address of the first edge server.

[0167] In the embodiment of the present application, the third IP address is different from the second IP address, so that the relevant network elements in the message forwarding process can identify the destination edge application server of the message based on the IP address.

[0168] The first edge server and the second edge server may be two different edge servers accessed by the terminal device through the same session. The first IP address may be the IP address of the first edge server in the local area network to which it belongs, and the second IP address may be the IP address of the second edge server in the local area network to which it belongs.

[0169] In one possible design, the third IP address is a local area network IP address newly allocated to the first edge server.

[0170] Exemplarily, EASDF can manage a resource pool of IP addresses; after detecting that the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, EASDF can select an idle IP address from the resource pool and assign it to the first edge server, and the idle IP address is the third IP address.

[0171] In some embodiments, the EASDF may establish a correspondence between the FQDN of the first edge server and the third IP address to make it clear that the third IP address is in use rather than idle. If the terminal device does not need to access the first edge server, the EASDF may delete the correspondence between the FQDN of the first edge server and the third IP address to reclaim the third IP address.

[0172] In another possible design, the third IP address may be a public IP address of the first edge server, or the third IP address may be a public IP address of another public server that provides the same service as the first edge server.

[0173] Exemplarily, after detecting that the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, the EASDF sends a fourth request message to the second DNS server, where the fourth request message is used to request a query of the public IP address of the first edge server or to request a query of the public IP addresses of other public servers that provide the same service as the first edge server. The EASDF receives a fourth response message sent from the second DNS server, where the fourth response message includes the third IP address of the first edge server, or the fourth response message includes the public IP addresses of other public servers that provide the same service as the first edge server.

[0174] As a possible implementation, EASDF records all edge servers currently accessed by the terminal device and records the IP addresses of these edge servers. After obtaining the first IP address of the first edge server, EASDF can compare the first IP address with the IP addresses of each edge server currently accessed by the terminal device. If the first IP address of the first edge server and the second IP address of the second edge server are the same, EASDF can allocate a third IP address to the first edge server and feed back a first response message containing the third IP address to the terminal device.

[0175] It should be understood that if the first IP address of the first edge server is different from the IP address of any edge server currently accessed by the terminal device, the EASDF may feed back a first response message including the first IP address to the terminal device.

[0176] In an embodiment of the present application, when the first IP address of the first edge server and the second IP address of the second edge server are the same, EASDF can feed back a first response message including a third IP address to the terminal device, so that during the subsequent message transmission between the terminal device and the first edge server and the second edge server, messages can be forwarded based on the different IP addresses of the two edge servers, thereby ensuring the success rate and accuracy of message forwarding.

[0177] In order to better understand the method provided by the present application, in the case where the third IP address is a local area network IP address newly allocated to the first edge server, the following is combined with Figure 5 The network architecture shown is introduced Figure 7 The complete process of the method shown, for details, please refer to Figure 8 It can be understood that the above Figure 7 The description of each feature in the method shown can be compared with the following Figure 8 The introduction of the various features in the methods shown draws on each other.

[0178] like Figure 8 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0179] S501: The terminal device sends a first request message to the EASDF, so that the EASDF receives the first request message from the terminal device.

[0180] S502: EASDF sends a first request message to the first DNS server, so that the first DNS server receives the first request message from EASDF.

[0181] S503: The first DNS server sends a first response message including the first IP address to the EASDF, so that the EASDF receives the first response message including the first IP address from the first DNS server.

[0182] S504: When the first IP address of the first edge server and the second IP address of the second edge server are the same, the EASDF allocates a third IP address to the first edge server and establishes a correspondence between the third IP address and the FQDN of the first edge server.

[0183] S505. EASDF sends a second request message to SMF, so that SMF receives the second request message from EASDF.

[0184] The second request message includes the third IP address and the first IP address. The second request message is used to trigger the SMF to establish a transmission channel between the terminal device and the first edge server based on the first IP address and the third IP address.

[0185] Optionally, the second request message may further include the DNAI of the first edge server. The embodiment of the present application does not limit the content of the second request message.

[0186] S506. SMF selects L-PSA and builds a NAT policy.

[0187] As a possible implementation, the SMF can select the L-PSA based on the first IP address, the third IP address and the DNAI, and construct a NAT policy, wherein the NAT policy is used to convert the first IP address and the third IP address of the message between the terminal device and the first edge server.

[0188] Optionally, the NAT policy may include a first policy and a second policy. The first policy is used to modify the destination address of the first message from the third IP address to the first IP address, and the first message is the message sent by the terminal device to the first edge server. The second policy is used to modify the source address of the second message from the first IP address to the third IP address, and the second message is the message sent by the first edge server to the terminal device.

[0189] Optionally, the NAT policy may also include an aging time. After the time for which no message related to the NAT policy is received reaches the aging time, the NAT policy may be determined to be invalid, so as to trigger the recovery process of the third IP address. It should be understood that by reasonably recovering the third IP address, the exhaustion of the IP address resource pool can be avoided, so as to ensure that other edge servers can be allocated corresponding LAN IP addresses when there is an address conflict.

[0190] It should be understood that since the first edge server considers its own IP address to be the first IP address, and the terminal device considers the IP address of the first edge server to be the third IP address, it is necessary to construct a NAT policy and send the NAT policy to the relevant network element (such as L-PSA) responsible for message forwarding between the terminal device and the first edge server for execution to ensure that the messages between the terminal device and the first edge server can be accurately transmitted.

[0191] S507: SMF sends a session creation / modification request message to L-PSA, so that L-PSA receives the session creation / modification request message, wherein the session creation / modification request message includes a NAT policy.

[0192] In some embodiments, after the L-PSA completes corresponding operations based on the session creation / modification request message, the L-PSA may send a session creation / modification response message to the SMF.

[0193] S508. SMF sends a second response message to EASDF, so that EASDF receives the second response message from SMF.

[0194] The second response message is used to respond to the second request message. Exemplarily, the second response message can be used to indicate that the transmission channel between the terminal device and the first edge server is successfully established.

[0195] In some embodiments, the second request message may be a ULCL insertion request message; correspondingly, the second response message may be a ULCL insertion completion message.

[0196] S509: EASDF sends a first response message including the third IP address to the terminal device, so that the terminal device receives the first response message including the third IP address from EASDF.

[0197] Based on the above steps S501-S509, the terminal device learns that the IP address of the first edge server is the third IP address, and the network side has established a transmission channel between the terminal device and the first edge server, so the terminal device can communicate with the first edge server based on the third IP address. Among them, the process of the terminal device sending the first message to the first edge server can refer to the following steps S510-S512; the process of the first edge server sending the second message to the terminal device can refer to the following steps S513-S515. It should be understood that the embodiment of the present application does not limit the execution sequence between steps S510-S512 and steps S513-S515.

[0198] S510: The terminal device sends a first message to the L-PSA, so that the L-PSA receives the first message from the terminal device.

[0199] The destination address of the first message is the third IP address.

[0200] S511. The L-PSA modifies the destination address of the first message from the third IP address to the first IP address based on the NAT policy.

[0201] S512: The L-PSA sends the modified first message to the first edge server, so that the first edge server receives the modified first message.

[0202] It should be understood that by modifying the destination address of the first message, after receiving the modified first message, the first edge server can know that the modified first message is a message sent to itself.

[0203] S513: The first edge server sends a second message to the L-PSA, so that the L-PSA receives the second message.

[0204] S514. The L-PSA modifies the source address of the second message from the first IP address to the third IP address based on the NAT policy.

[0205] S515. The L-PSA sends the modified second message to the terminal device, so that the terminal device receives the modified second message.

[0206] It should be understood that by modifying the source address of the second message, after receiving the modified second message, the terminal device can learn that the sender of the modified second message is the first edge server.

[0207] In some embodiments, due to the limitation of the number of IP addresses, the LAN IP addresses allocated by EASDF to the edge servers need to be recycled so that other edge servers can be allocated corresponding IP addresses in case of address conflicts. Fig. 9 The method shown in the figure illustrates the IP address recovery process provided in the embodiment of the present application. Fig. 9 As shown, an embodiment of the present application provides a communication method, the method comprising the following steps:

[0208] S601. L-PSA detects whether a reporting condition for a NAT policy timeout event is met.

[0209] Optionally, the reporting condition includes: the time for not receiving the message related to the NAT policy reaches the aging time. The message related to the NAT policy may be a message whose source address or destination address is the third IP address.

[0210] S602. When the reporting conditions are met, the L-PSA sends a NAT policy timeout event to the SMF, so that the SMF receives the NAT policy timeout event.

[0211] The NAT policy timeout event may include at least one of a timeout period and an identifier of the NAT policy. The timeout period is the time when no message related to the NAT policy is received. The embodiment of the present application does not limit the content of the NAT policy timeout event.

[0212] S603: SMF instructs L-PSA to delete the NAT policy.

[0213] S604: SMF sends a third request message to EASDF, so that EASDF receives the third request message from SMF.

[0214] The third request message is used to request deletion of the correspondence between the FQDN of the first edge server and the third IP address.

[0215] S605: The EASDF deletes the correspondence between the FQDN of the first edge server and the third IP address based on the third request message.

[0216] After successfully deleting the corresponding relationship, the EASDF may set the third IP address to an idle state (or an unallocated state). When there is an address conflict in other edge servers, the EASDF may reallocate the third IP address to other edge servers.

[0217] S606. EASDF sends a third response message to SMF, so that SMF receives the third response message from EASDF.

[0218] The third response message is used to respond to the third request message. Specifically, the third response message is used to indicate the deletion result of the correspondence between the FQDN of the first edge server and the third IP address. The deletion result can be a successful deletion or a failed deletion.

[0219] In some embodiments, the third request message can be named a DNS policy update request message; when the corresponding relationship is successfully deleted, the third response message can be named a DNS policy update pass message.

[0220] In an embodiment of the present application, the aging mechanism of the NAT policy is used to realize the recovery of the LAN IP address (such as the third IP address mentioned above) allocated to the edge server, so as to alleviate the problem of limited IP address resources, so as to ensure that more edge servers can be allocated corresponding LAN IP addresses when there is an address conflict, thereby ensuring normal communication between the edge server and the terminal device.

[0221] In order to better understand the method provided by the present application, when the third IP address is the public IP address of the first edge server, the following Figure 5 The network architecture shown is introduced Figure 7 The complete process of the method shown. It can be understood that the above Figure 7 The description of each feature in the method shown can be compared with the following Fig.10 The introduction of the various features in the methods shown draws on each other.

[0222] like Fig.10 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0223] S701: The terminal device sends a first request message to the EASDF, so that the EASDF receives the first request message from the terminal device.

[0224] S702: EASDF sends a first request message to the first DNS server, so that the first DNS server receives the first request message from EASDF.

[0225] S703: The first DNS server sends a first response message including the first IP address to the EASDF, so that the EASDF receives the first response message including the first IP address from the first DNS server.

[0226] S704: When the first IP address of the first edge server and the second IP address of the second edge server are the same, the EASDF sends a fourth request message to the second DNS server, so that the second DNS server receives the fourth request message.

[0227] S705: The second DNS server sends a fourth response message to the EASDF, so that the EASDF receives the fourth response message including the third IP address.

[0228] S706. EASDF sends the DNS query result to SMF, so that SMF receives the DNS query result.

[0229] The DNS query result may include the third IP address, DNAI, and FQDN of the first edge server.

[0230] S707. The EASDF sends a first response message including the third IP address to the terminal device, so that the terminal device receives the first response message including the third IP address from the EASDF.

[0231] It should be understood that, since the third IP address is the public network address of the first edge server, there is no need to trigger the ULCL insertion process, and the terminal device can access the first edge server through the public network exit of the PSA.

[0232] like Fig.11 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0233] S801: The UDR receives a fifth request message, wherein the fifth request message is used to request information of a registered edge server.

[0234] The information of the edge server includes the IP address of the edge server. Optionally, the information of the edge server also includes at least one of the following: the FQDN of the edge server, the DNAI of the edge server. The embodiment of the present application does not limit the content carried by the information of the edge server.

[0235] As a possible implementation, the UDR receives the fifth request message sent by the edge server (or the AF corresponding to the edge server) through the NEF. Fig.12 As shown, the AF (or edge server) sends the fifth request message to the NEF; the NEF forwards the fifth request message to the UDR. Exemplarily, the name of the fifth request message when transmitted between the AF (or edge server) and the NEF may be a Nef_EASD deployment_Create_Request message; the name of the fifth request message when transmitted between the NEF and the UDR may be a Nudr_DM_Create_Request message.

[0236] S802: When it is identified that the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs, the UDR sends a fifth response message indicating that the registration has failed.

[0237] Optionally, the IP address conflict of the two edge servers may refer to the IP addresses of the two edge servers being the same. In the embodiment of the present application, after receiving the fifth request message, the UDR may traverse the IP addresses of all registered edge servers under other DNAIs, and in the traversal process, find that there is an IP address of a registered edge server that is the same as the IP address of the edge server to be registered, that is, determine that there is an IP address conflict.

[0238] Optionally, the fifth response message may include a failure reason, which is used to indicate that the IP address of the edge server conflicts with the IP addresses of other registered edge servers. The failure reason may also be named as a reason for rejecting registration, which is not limited. In this way, after learning the failure reason, the edge server can actively change its own IP address and re-initiate the registration process to achieve the purpose of registration.

[0239] Of course, the fifth response message may also carry other content, which is not limited in the embodiment of the present application.

[0240] As a possible implementation, the UDR sends a fifth response message to the edge server (or the AF corresponding to the edge server) through the NEF. Fig.12 As shown, the UDR sends the fifth response message to the NEF; the NEF forwards the fifth response message to the AF (or edge server). Exemplarily, the name of the fifth response message when transmitted between the UDF and the NEF may be a Nudr_DM_Create_Reject message; the name of the fifth response message when transmitted between the NEF and the AF (or edge server) may be a Nef_EASDdeployment_Create_Reject message.

[0241] In the embodiment of the present application, during the edge server registration process, the UDR checks the IP address of the edge server to avoid conflicts between the IP address of the edge server and the IP address of the edge server registered under other DNAIs. In this way, in the subsequent process of the terminal device communicating with the registered edge server, there will be no situation where one IP address corresponds to two edge servers at the same time, thereby ensuring normal communication between the terminal device and the registered edge server.

[0242] like Fig.13 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0243] S901: SMF receives a sixth request message, wherein the sixth request message is used to trigger a ULCL insertion process.

[0244] The sixth request message includes the first IP address of the first edge server.

[0245] Optionally, the sixth request message may also include at least one of the following parameters: DNAI, APP identifier.

[0246] As a possible implementation manner, the SMF receives the sixth request message from the AF or the first edge server. Specifically, the SMF may receive the sixth request message from the AF or the first edge server through relevant network elements such as the PCF and the NEF.

[0247] S902: When the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, the SMF configures a third IP address for the first edge server, and performs a ULCL insertion process based on the third IP address and the first IP address.

[0248] The third IP address is different from the first IP address, so that the relevant network elements in the message forwarding process can identify the destination edge application server of the message based on the IP address.

[0249] The first edge server and the second edge server may be two different edge servers accessed by the terminal device through the same session. The first IP address may be the IP address of the first edge server in the local area network to which it belongs, and the second IP address may be the IP address of the second edge server in the local area network to which it belongs.

[0250] In one possible design, the third IP address is an IP address newly allocated to the first edge server in the local area network to which it belongs.

[0251] As a possible implementation, SMF records all edge servers currently accessed by the terminal device and records the IP addresses of these edge servers. After obtaining the first IP address of the first edge server, SMF can compare the first IP address with the IP addresses of each edge server currently accessed by the terminal device. When the first IP address of the first edge server and the second IP address of the second edge server are the same, SMF can select an idle IP address from the resource pool and assign it to the first edge server, and the idle IP address is the third IP address. SMF performs the ULCL insertion process based on the third IP address and the first IP address.

[0252] In some embodiments, after completing the ULCL insertion process, the SMF may send a sixth response message, wherein the sixth response message is used to indicate the result of the ULCL insertion process. Optionally, when the ULCL insertion process is successful, the sixth response message includes the third IP address.

[0253] In an embodiment of the present application, in the event of an IP address conflict between two edge servers, the SMF may allocate a new IP address (i.e., a third IP address) to the first edge server, and perform a ULCL insertion process based on the third IP address and the first IP address, thereby solving the problem of message forwarding failure caused by the IP address conflict.

[0254] In order to better understand the method provided by the present application, Figure 5 The network architecture shown is introduced Fig.13The complete process of the method shown, for details, please refer to Fig.14 It can be understood that the above Fig.13 The description of each feature in the method shown can be compared with the following Fig.14 The introduction of the various features in the methods shown draws on each other.

[0255] like Fig.14 As shown, a communication method provided in an embodiment of the present application comprises the following steps:

[0256] S1001. The terminal device is successfully registered and a PDU session is created.

[0257] Among them, the registration process and the PDU session creation process can refer to the relevant technology, which will not be described in detail.

[0258] S1002: The AF sends a sixth request message to the NEF, so that the NEF receives the sixth request message from the AF.

[0259] S1003. The NEF sends a sixth request message to the PCF, so that the PCF receives the sixth request message from the NEF.

[0260] S1004. The PCF sends a sixth request message to the SMF, so that the SMF receives the sixth request message from the PCF.

[0261] S1005: When the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, the SMF configures a third IP address for the first edge server.

[0262] S1006. SMF sends a seventh request message to L-PSA, so that L-PSA receives the seventh request message.

[0263] The seventh request message includes a NAT policy, and the NAT policy is used to convert the first IP address and the third IP address of the message between the terminal device and the first edge server.

[0264] Optionally, the NAT policy may include a first policy and a second policy. The first policy is used to modify the destination address of the first message from the third IP address to the first IP address, and the first message is the message sent by the terminal device to the first edge server. The second policy is used to modify the source address of the second message from the first IP address to the third IP address, and the second message is the message sent by the first edge server to the terminal device.

[0265] Optionally, the NAT policy may also include an aging time. After the time for which no message related to the NAT policy is received reaches the aging time, the NAT policy may be determined to be invalid, so as to trigger the recovery process of the third IP address. It should be understood that by reasonably recovering the third IP address, the exhaustion of the IP address resource pool can be avoided, so as to ensure that other edge servers can be allocated corresponding LAN IP addresses when there is an address conflict.

[0266] In some embodiments, after the L-PSA completes a corresponding operation based on the seventh request message, the L-PSA may send a seventh response message to the SMF.

[0267] Optionally, the seventh request message can be named a session creation / modification request message, and the seventh response message can be named a session creation / modification response message, which is not limited in the embodiment of the present application.

[0268] It should be understood that step S1006 is a specific implementation of the ULCL insertion process performed by the above-mentioned SMF based on the third IP address and the first IP address.

[0269] S1007. SMF sends a sixth response message to PCF, so that PCF receives the sixth response message from SMF.

[0270] S1008. The PCF sends a sixth response message to the NEF, so that the NEF receives the sixth response message from the PCF.

[0271] S1009. The NEF sends a sixth response message to the AF, so that the AF receives the sixth response message from the NEF.

[0272] It should be understood that the operation performed by the AF in the above step S1002 or S1009 can be replaced by the first edge server.

[0273] In some embodiments, SMF can recycle IP addresses based on the aging mechanism of NAT policy. Exemplarily, L-PSA detects whether the reporting conditions of NAT policy timeout event are met. When the reporting conditions are met, L-PSA sends a NAT policy timeout event to SMF so that SMF receives the NAT policy timeout event. Based on the NAT policy timeout event, SMF can set the third IP address to an idle state (or an unallocated state). When there is an address conflict in other edge servers, EASDF can reallocate the three IP addresses to other edge servers. Optionally, the reporting conditions include: the time for not receiving the message related to the NAT policy reaches the aging time. Among them, the message related to the NAT policy can be a message whose source address or destination address is the third IP address.

[0274] In some embodiments, after the third IP address is reclaimed, the SMF may send a notification message to the AF or the first edge server to notify that the third IP address has been reclaimed.

[0275] The above mainly introduces the scheme provided by the present application from the perspective of interaction between various network elements. Accordingly, the present application also provides a communication device, which may be the EASDF in the above method embodiment, or a device including the above EASDF, or a component that can be used for EASDF; or, the communication device may be the UDR network element in the above method embodiment, or a device including the above UDR network element, or a component that can be used for UDR; or, the communication device may be the SMF in the above method embodiment, or a device including the above SMF, or a component that can be used for SMF. It can be understood that the above EASDF, UDR or SMF, etc., in order to realize the above functions, include hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should easily realize that, in combination with the units and algorithm operations of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0276] For example, when the functional modules are divided in an integrated manner, Fig.15 The structure diagram of a communication device 30 is shown. The communication device 30 includes a processing module 301 and an interface module 302. The processing module 301, which may also be referred to as a processing unit, is used to perform operations other than transceiver operations, and may be, for example, a processing circuit or a processor. The interface module 302, which may also be referred to as an interface unit, is used to perform transceiver operations, and may be, for example, an interface circuit, a transceiver, a transceiver or a communication interface.

[0277] In some embodiments, the communication device 30 may further include a storage module ( Fig.15 ), for storing program instructions and data.

[0278] Exemplarily, the communication device 30 is used to implement the EASDF function. For example, the communication device 30 may be Figure 7-Figure 10 EASDF in .

[0279] The interface module 302 is used to receive a first request message sent by a terminal device, and the first request message is used to query the IP address of the first edge server; the IP address of the first edge server queried from the first DNS server is the first IP address. The processing module 301 is used to detect whether the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device. The interface module 302 is also used to send a first response message to the terminal device when the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device. The first response message includes a third IP address of the first edge server, and the third IP address is different from the second IP address.

[0280] In a possible implementation, the third IP address is a local area network IP address newly allocated to the first edge server.

[0281] In one possible implementation, the interface module 302 is also used to send a second request message to the SMF, the second request message includes a third IP address and a first IP address, and the second request message is used to trigger the SMF to establish a transmission channel between the first edge server and the terminal device based on the third IP address and the first IP address; and receive a second response message sent by the SMF to respond to the second request message.

[0282] In a possible implementation, the processing module 301 is further configured to establish a correspondence between the FQDN of the first edge server and the third IP address.

[0283] In a possible implementation, the interface module 302 is further used to receive a third request message sent by the SMF, where the third request message is used to request deletion of the correspondence between the FQDN of the first edge server and the third IP address. The processing module 301 is further used to delete the correspondence between the FQDN of the first edge server and the third IP address based on the third request message.

[0284] In a possible implementation, the interface module 302 is further configured to send a third response message to the SMF, where the third response message is used to indicate a deletion result of the correspondence between the FQDN of the first edge server and the third IP address.

[0285] In a possible implementation, the third IP address is a public IP address of the first edge server.

[0286] In one possible implementation, the interface module 302 is also used to send a fourth request message to the second DNS server, where the fourth request message is used to query the public IP address of the first edge server; and receive a fourth response message from the second DNS server, where the fourth response message is used to indicate that the public IP address of the first edge server is the third IP address.

[0287] Alternatively, the communication device is used to implement the function of the UDR. For example, the communication device 30 may be Fig.11 or Fig.12 The UDR in .

[0288] The interface module 302 is used to receive a fifth request message, the fifth request message is used to request the registration of edge server information, the edge server information includes the IP address of the edge server. The processing module 301 is used to detect whether the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs. The interface module 302 is also used to send a fifth response message indicating a registration failure when the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs.

[0289] In a possible implementation, the fifth response message includes a failure reason, where the failure reason is used to indicate that the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs.

[0290] In a possible implementation manner, the interface module 302 is specifically configured to receive, through the NEF, the fifth request message sent by the AF; and send, through the NEF, a fifth response message to the AF.

[0291] Alternatively, the communication device is used to implement the function of the SMF. For example, the communication device 30 may be Fig.13 or Fig.14 SMF in.

[0292] The interface module 302 is used to receive a sixth request message, the fifth request message is used to trigger the ULCL insertion process, and the sixth request message includes the first IP address of the first edge server. The processing module 301 is used to configure a third IP address for the first edge server when the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, and perform the ULCL insertion process based on the third IP address and the first IP address.

[0293] In a possible implementation, the interface module 302 is further configured to send a seventh request message to the L-PSA, where the seventh request message includes a NAT policy, where the NAT policy is configured to convert the address of the message between the first IP address and the third IP address.

[0294] In one possible implementation, the NAT policy includes a first policy and a second policy, the first policy is used to change the destination address of the first message from the third IP address to the first IP address, and the second policy is used to change the source address of the second message from the first IP address to the third IP address.

[0295] In a possible implementation, the NAT policy further includes an aging time.

[0296] In a possible implementation, the interface module 302 is further configured to send a sixth response message, where the sixth response message is used to indicate a result of the ULCL insertion process.

[0297] In a possible implementation, when the ULCL insertion process is successful, the sixth response message includes the third IP address.

[0298] In a simple embodiment, those skilled in the art will appreciate that the communication device 30 may be used Figure 6 For example, Figure 6 The processor 201 in the communication device 30 can call the computer execution instructions stored in the memory 203 to enable the communication device 30 to execute the method described in the above method embodiment.

[0299] For example, Fig.15 The functions / implementation processes of the processing module 301 and the interface module 302 can be Figure 6 The processor 201 in the embodiment calls the computer execution instruction stored in the memory 203 to implement. Or, Fig.15 The function / implementation process of the processing module 301 in Figure 6 The processor 201 in the embodiment calls the computer execution instruction stored in the memory 203 to implement, Fig.15 The function / implementation process of the interface module 302 in Figure 6 This is achieved by the communication interface 204 in .

[0300] It is understandable that one or more of the above modules or units can be implemented by software, hardware or a combination of the two. When any of the above modules or units is implemented in software, the software exists in the form of computer program instructions and is stored in a memory, and a processor can be used to execute the program instructions and implement the above method flow. The processor can be built into an SoC (system on chip) or an ASIC, or it can be an independent semiconductor chip. In addition to the core used to execute software instructions for calculation or processing in the processor, it can also further include necessary hardware accelerators, such as field programmable gate arrays (FPGA), PLDs (programmable logic devices), or logic circuits that implement dedicated logic operations.

[0301] When the above modules or units are implemented in hardware, the hardware can be any one or any combination of a CPU, a microprocessor, a digital signal processing (DSP) chip, a microcontroller unit (MCU), an artificial intelligence processor, an ASIC, a SoC, an FPGA, a PLD, a dedicated digital circuit, a hardware accelerator or a non-integrated discrete device, which can run the necessary software or not rely on the software to execute the above method flow.

[0302] Optionally, the present application also provides a chip system, including: at least one processor and an interface, the at least one processor is coupled to a memory through the interface, and when the at least one processor executes a computer program or instruction in the memory, the method in any of the above method embodiments is executed. In one possible implementation, the chip system also includes a memory. Optionally, the chip system can be composed of a chip, or it can include a chip and other discrete devices, which is not specifically limited in the present application.

[0303] Optionally, the present application also provides a computer-readable storage medium. All or part of the processes in the above method embodiments can be completed by a computer program to instruct the relevant hardware, and the program can be stored in the above computer-readable storage medium. When the program is executed, it can include the processes of the above method embodiments. The computer-readable storage medium can be an internal storage unit of the communication device of any of the above embodiments, such as a hard disk or memory of the communication device. The above computer-readable storage medium can also be an external storage device of the above communication device, such as a plug-in hard disk, a smart memory card (smart media card, SMC), a secure digital (secure digital, SD) card, a flash card (flash card), etc. equipped on the above communication device. Further, the above computer-readable storage medium can also include both the internal storage unit of the above communication device and an external storage device. The above computer-readable storage medium is used to store the above computer program and other programs and data required by the above communication device. The above computer-readable storage medium can also be used to temporarily store data that has been output or is to be output.

[0304] Optionally, the present application also provides a computer program product. All or part of the processes in the above method embodiments can be completed by a computer program to instruct related hardware, and the program can be stored in the above computer program product. When the program is executed, it can include the processes of the above method embodiments.

[0305] Optionally, the present application also provides a computer instruction. All or part of the processes in the above method embodiments can be completed by computer instructions to instruct related hardware (such as computers, EASDF network elements, UDR network elements or SMF network elements, etc.). The program can be stored in the above computer-readable storage medium or in the above computer program product.

[0306] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0307] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0308] The units described as separate components may or may not be physically separated, and the components shown as units may be one physical unit or multiple physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0309] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0310] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A communication method, characterized in that: Applied to the edge application server discovery function EASDF, the method comprises: Receiving a first request message sent by a terminal device, where the first request message is used to query an Internet Protocol IP address of a first edge server; The IP address of the first edge server queried from the first domain name system DNS server is the first IP address; When the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, a first response message is sent to the terminal device, wherein the first response message includes a third IP address of the first edge server, and the third IP address is different from the second IP address.

2. The method according to claim 1, characterized in that The third IP address is an IP address newly allocated to the first edge server in the local area network to which it belongs.

3. The method according to claim 2, characterized in that The method further comprises: Sending a second request message to a session management function SMF, where the second request message includes the third IP address and the first IP address, and the second request message is used to trigger the SMF to establish a transmission channel between the first edge server and the terminal device based on the third IP address and the first IP address; Receive a second response message sent by the SMF to respond to the second request message.

4. The method according to claim 2, characterized in that: The method further comprises: A correspondence between the fully qualified domain name FQDN of the first edge server and the third IP address is established.

5. The method according to claim 4, characterized in that The method further comprises: Receive a third request message sent by the SMF, where the third request message is used to request deletion of the correspondence between the FQDN of the first edge server and the third IP address; Based on the third request message, the correspondence between the FQDN of the first edge server and the third IP address is deleted.

6. The method according to claim 5, characterized in that The method further comprises: A third response message is sent to the SMF, where the third response message is used to indicate a deletion result of the correspondence between the FQDN of the first edge server and the third IP address.

7. The method according to any one of claims 1 to 6, characterized in that: The third IP address is the public IP address of the first edge server, or the third IP address is the public IP address of another public server that provides the same service as the first edge server.

8. The method according to claim 7, characterized in that The method further comprises: Sending a fourth request message to the second DNS server, where the fourth request message is used to query the public IP address of the first edge server; A fourth response message is received from the second DNS server, where the fourth response message is used to indicate that the public IP address of the first edge server is the third IP address.

9. A communication method, characterized in that: Applied to the unified data warehousing function UDR, the method includes: receiving a fifth request message, wherein the fifth request message is used to request registration of information of an edge server, wherein the information of the edge server includes an IP address of the edge server; When it is identified that the IP address of the edge server conflicts with the IP addresses of edge servers registered under other DNAIs, a fifth response message indicating registration failure is sent.

10. The method according to claim 9, characterized in that The fifth response message includes a failure reason, where the failure reason is used to indicate that the IP address of the edge server conflicts with the IP addresses of other edge servers registered under the DNAI.

11. The method according to claim 9 or 10, characterized in that: The receiving a fifth request message comprises: Receiving, through the network opening function NEF, the fifth request message sent by the application function AF; The sending of the fifth response message comprises: The fifth response message is sent to the AF through the NEF.

12. A communication method, characterized in that: Applied to SMF, the method comprises: receiving a sixth request message, the fifth request message being used to trigger an uplink splitter ULCL insertion process, the sixth request message including a first IP address of the first edge server; When the first IP address of the first edge server is the same as the second IP address of the second edge server currently accessed by the terminal device, a third IP address is configured for the first edge server, and a ULCL insertion process is performed based on the third IP address and the first IP address.

13. The method according to claim 12, characterized in that The ULCL insertion process based on the third IP address and the first IP address includes: A seventh request message is sent to the L-PSA, where the seventh request message includes a network address translation NAT policy, where the NAT policy is used to translate the address of the message between the first IP address and the third IP address.

14. The method according to claim 13, characterized in that The NAT policy includes a first policy and a second policy, wherein the first policy is used to modify the destination address of the first message from the third IP address to the first IP address, and the second policy is used to modify the source address of the second message from the first IP address to the third IP address.

15. The method according to claim 14, characterized in that The NAT policy also includes an aging time.

16. The method according to any one of claims 12 to 15, characterized in that The method further comprises: A sixth response message is sent, where the sixth response message is used to indicate a result of the ULCL insertion procedure.

17. The method according to claim 16, characterized in that In the case that the ULCL insertion process is successful, the sixth response message includes the third IP address.

18. A communication device, characterized in that: The method comprises a unit or module for executing the method according to any one of claims 1 to 8, or comprises a unit or module for executing the method according to any one of claims 9 to 11, or comprises a unit or module for executing the method according to any one of claims 12 to 17.

19. A communication device, characterized in that: include: A processor, the processor is coupled to a memory, the memory is used to store programs or instructions, when the program or instructions are executed by the processor, the device performs the method as claimed in any one of claims 1 to 8, or performs the method as claimed in any one of claims 9 to 11, or performs the method as claimed in any one of claims 12 to 17.

20. A computer-readable storage medium having a computer program or instruction stored thereon, characterized in that: When the computer program or instructions are executed, the computer performs the method according to any one of claims 1 to 8, or the method according to any one of claims 9 to 11, or the method according to any one of claims 12 to 17.

21. A computer program product, comprising computer program code, characterized in that: When the computer program code runs on a computer, the computer is enabled to implement the method of any one of claims 1 to 8, or the method of any one of claims 9 to 11, or the method of any one of claims 12 to 17.

Images