WO2023011087A1

WO2023011087A1 - Communication method and communication apparatus

Info

Publication number: WO2023011087A1
Application number: PCT/CN2022/103857
Authority: WO
Inventors: 曹德全; 陶振宇
Original assignee: 华为技术有限公司
Priority date: 2021-08-06
Filing date: 2022-07-05
Publication date: 2023-02-09
Also published as: CN115915096A

Abstract

The present application provides a communication method and a communication apparatus. The method comprises: a first core network device receives a first request message, the first request message being used for requesting a first session of a terminal device to be switched from first access technology to second access technology, and the first request message comprising a first EBI of the first session; the first core network device sends an update message to a PCF and/or a CHF, the update message comprising a first PDU session identifier, the first PDU session identifier being generated according to the first EBI and a first preset value. According to the present application, the first PDU session identifier is carried in the update message, so that the PCF and/or the CHF can update the PDU session identifier of the first session in a timely manner, avoiding repetition of the session identifier of the terminal device, such that multiple services of the terminal device can be performed simultaneously, thereby improving user experience.

Description

A communication method and communication device

This application claims the priority of a Chinese invention patent application with an application date of August 6, 2021, an application number of 202110903825.4, and an application name of "A Communication Method and Communication Device", the entire contents of which are incorporated in this application by reference .

technical field

The present application relates to the communication field, and more specifically, to a communication method and a communication device.

Background technique

With the official commercialization of the 5th Generation (5th Generation, 5G) network, 5G network will appear in our daily life. However, in the initial stage of 5G network commercialization, limited by the maturity of technology and the support of terminal equipment, 5G network cannot cover a large area, and 5G network and 4th generation (4th Generation, 4G) network will coexist for a long time. a period of time. In a typical scenario, the core network equipment in the system is transformed into a 5G core network (5G corenet, 5GC), and the access network equipment in the 4G system is used. In this networking situation, there will be 5G network and Interoperability between 4G networks.

When a terminal device needs to create a session, if the terminal device has 4G and 5G interoperability, the protocol data unit (protocol data unit, PDU) session (PDU session) identifier is allocated by the terminal device and carried to the network side. If the terminal device does not have the interoperability between 4G and 5G, according to the provisions of the agreement, the PDU session identifier is determined by the session management function (session management function, SMF)/packet data network gateway-control plane ( The packet data network gateway control (PGW-C) network element is based on the evolved packet system (EPS) bearer allocated by the mobility management entity (mobility management entity, MME) or the evolved packet data gateway (ePDG). The logo (EPS bearer identity, EBI) is responsible for generation.

For terminal equipment that does not have 4G and 5G interoperability, if it is in the 3rd generation partnership project (3rd generation partnership project, 3GPP) access network and non-3rd generation partnership project (non-3rd generation partnership project, N3GPP) ) switching between access networks, the first session created by it will also switch. However, in the existing protocol, the co-located SMF/PGW-C network element does not update the PDU session identifier corresponding to the first session to the policy control function (policy control function, PCF) network element and/or charging function (charging function, CHF) network element. In this way, when a terminal device creates a second session, two identical PDU session identifiers may appear for the same terminal device on the PCF network element and/or CHF network element, which may be considered as the repeated activation of the same service In this scenario, the services corresponding to the two sessions cannot be performed at the same time, affecting user experience.

Contents of the invention

The present application provides a communication method and a communication device, so that multiple services of a terminal device can be performed simultaneously, thereby improving user experience.

In a first aspect, a communication method is provided, and the method is executed by a first core network device, and may also be executed by a module or unit included in the first core network device. The method includes: receiving a first request message from a second core network device, where the first request message is used to request the first session of the terminal device to be switched from the first access technology to the second access technology, the first request message A request message includes the first evolved packet system bearer identifier EBI of the first session; an update message is sent to the policy control function network element and/or the charging function network element, the update message includes the first PDU session identifier, the The first PDU session identifier is generated according to the first EBI and a first preset value.

According to the solution of this application, when the first session of the terminal device needs to be switched from the first access technology to the second access technology, the second core network device will send the first request message, and the first core network device will After a request message, an update message is sent to the policy control function network element and/or the charging function network element respectively, and the update message carries the first PDU session identifier generated according to the first EBI. In other words, this application carries the first PDU session identifier in the update message, so that the policy control function network element and/or the charging function network element can update the PDU session identifier of the first session in time, avoiding the session identifier of the session established later Repeat, so that multiple services of the terminal device can be performed at the same time, improving user experience.

With reference to the first aspect, in some implementation manners of the first aspect, the method further includes: generating the first PDU session identifier according to the first EBI and the first preset value.

With reference to the first aspect, in some implementation manners of the first aspect, the first preset value is determined according to the second access technology.

With reference to the first aspect, in some implementations of the first aspect, the first access technology is a 3rd Generation Partnership Project 3GPP access technology, and the second access technology is a non-3rd Generation Partnership Project N3GPP access technology.

With reference to the first aspect, in some implementation manners of the first aspect, the second core network device is an evolved packet data gateway ePDG.

With reference to the first aspect, in some implementation manners of the first aspect, the first preset value is 80.

With reference to the first aspect, in some implementation manners of the first aspect, the first access technology is an N3GPP access technology, and the second access technology is a 3GPP access technology.

With reference to the first aspect, in some implementation manners of the first aspect, the second core network device is a mobility management entity (MME).

With reference to the first aspect, in some implementation manners of the first aspect, the first preset value is 64.

With reference to the first aspect, in some implementation manners of the first aspect, the first core network device is a session management function SMF/packet data network gateway-control plane PGW-C network element.

With reference to the first aspect, in some implementation manners of the first aspect, the first EBI is used to identify the first session.

In a second aspect, a communication method is provided. The method is executed by a network element with a policy control function, and may also be executed by a module or unit included in the network element with a policy control function. The method includes: receiving an update message from a first core network device, where the update message includes a first PDU session identifier, the first PDU session identifier is generated according to a first EBI, and the first EBI is used to identify a terminal device The first session of the first PDU; saving the mapping relationship between the identifier of the terminal device and the identifier of the first PDU session.

In a third aspect, a communication method is provided, and the method is executed by a network element with a charging function, and may also be executed by a module or unit included in the network element with a charging function. The method includes: receiving an update message from a first core network device, where the update message includes a first PDU session identifier, the first PDU session identifier is generated according to a first EBI, and the first EBI is used to identify a terminal device The first session of the first PDU; saving the mapping relationship between the identifier of the terminal device and the identifier of the first PDU session.

In a fourth aspect, a communication method is provided, and the method is executed by a first core network device, and may also be executed by a module or unit included in the first core network device. The method includes: receiving a first request message from a second core network device, the first request message is used to request to create a first session of the terminal device through a first access technology, the first request message includes the The first evolved packet system bearer identifier EBI of the first session; when it is determined that the first PDU session identifier is a duplicate identifier of the terminal device, send a creation message to the policy control function network element and/or the charging function network element, the The creation message includes a second PDU session identifier, the second PDU session identifier is different from the first PDU session identifier, and the first PDU session identifier is generated according to the first EBI and a first preset value.

According to the solution of this application, when the terminal device needs to establish the first session through the first access technology, the second core network device will send the first request message, and the first core network device will send the first request message to the The network element with the policy control function and/or the network element with the charging function sends a creation message respectively, and the creation message carries a second PDU session identifier, and the second PDU session identifier is different from the first PDU session identifier, wherein the first PDU session The identifier is generated according to the first EBI and the first preset value. In other words, the present application carries the second PDU session identifier different from the first PDU session identifier in the creation message, so as to prevent the policy control function network element and/or the charging function network element from receiving the same PDU session identifier as the first session. Session identification, so that multiple services of the terminal device can be performed at the same time, improving user experience.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the method further includes: generating the first PDU session identifier according to the first EBI and the first preset value; The EBI and a second preset value generate the second PDU session identifier, and the second preset value is different from the first preset value.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the method further includes: determining that the first PDU session identifier is a duplicate identifier of the terminal device.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, before receiving the first request message, the method further includes: receiving a second request message, where the second request message is used to request to pass the first request message The access technology creates a second session, the second request message includes a second EBI of the second session; and a third PDU session identifier is generated according to the second EBI and a first preset value. The determining that the first PDU session identifier is a duplicate identifier of the terminal device includes: determining that the third PDU session identifier is the same as the first PDU session identifier.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first preset value is determined according to the first access technology, the second preset value is determined according to the first preset value, The second preset value is different from the first preset value.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first access technology is a 3GPP access technology.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the second core network device is a mobility management entity (MME).

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first preset value is 64.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first access technology is an N3GPP access technology.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the second core network device is an evolved packet data gateway ePDG.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first preset value is 80.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first core network device is a session management function SMF/packet data network gateway-control plane PGW-C network element.

With reference to the fourth aspect, in some implementation manners of the fourth aspect, the first EBI is used to identify the first session, and the second EBI is used to identify the second session.

In a fifth aspect, a communication device is provided, and the device may be a first core network device. The apparatus includes: a transceiving unit, configured to receive a first request message from a second core network device, and the first request message is used to request the first session of the terminal device to switch from the first access technology to the second access technology technology, the first request message includes the first evolved packet system bearer identifier EBI of the first session; the transceiver unit is further configured to: send an update message to a policy control function network element and/or a charging function network element, The update message includes a first PDU session identifier, and the first PDU session identifier is generated according to the first EBI and a first preset value.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the apparatus further includes: a processing unit configured to generate the first PDU session identifier according to the first EBI and the first preset value.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the first preset value is determined according to the second access technology.

With reference to the fifth aspect, in some implementations of the fifth aspect, the first access technology is a 3rd Generation Partnership Project 3GPP access technology, and the second access technology is a non-3rd Generation Partnership Project N3GPP access technology.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the second core network device is an evolved packet data gateway ePDG.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the first preset value is 80.

With reference to the fifth aspect, in some implementations of the fifth aspect, the first access technology is an N3GPP access technology, and the second access technology is a 3GPP access technology.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the second core network device is a mobility management entity (MME).

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the first preset value is 64.

With reference to the fifth aspect, in some implementation manners of the fifth aspect, the first core network device is a session management function SMF/packet data network gateway-control plane PGW-C network element.

In a sixth aspect, a communication device is provided, and the device may be a network element with a policy control function. The device includes: a transceiver unit, configured to receive an update message from a first core network device, the update message includes a first PDU session identifier, the first PDU session identifier is generated according to a first EBI, and the first EBI A first session for identifying a terminal device; a processing unit configured to save a mapping relationship between the terminal device identifier and the first PDU session identifier.

In a seventh aspect, a communication device is provided, and the device can be executed by a charging function network element. The device includes: a transceiver unit, configured to receive an update message from a first core network device, the update message includes a first PDU session identifier, the first PDU session identifier is generated according to a first EBI, and the first EBI A first session for identifying a terminal device; a processing unit configured to save a mapping relationship between the terminal device identifier and the first PDU session identifier.

In an eighth aspect, a communication device is provided, and the device may be a first core network device. The apparatus includes: a transceiver unit, configured to receive a first request message from a second core network device, where the first request message is used to request to create a first session of a terminal device through a first access technology, and the first The request message includes the first evolved packet system bearer identifier EBI of the first session; the transceiver unit is further configured to: when determining that the first PDU session identifier is a duplicate identifier of the terminal device, send the policy control function network element and /or the charging function network element sends a creation message, the creation message includes a second PDU session identifier, the second PDU session identifier is different from the first PDU session identifier, and the first PDU session identifier is based on the first PDU session identifier An EBI and a first default value are generated.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the apparatus further includes: a processing unit configured to generate the first PDU session identifier according to the first EBI and the first preset value; The first EBI and a second preset value generate the second PDU session identifier, and the second preset value is different from the first preset value.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the processing unit is further configured to: determine that the first PDU session identifier is a duplicate identifier of the terminal device.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the transceiver unit is further configured to: receive a second request message, where the second request message is used to request to create a second session, the second request message includes a second EBI of the second session; the processing unit is further configured to: generate a third PDU session identifier according to the second EBI and a first preset value. The processing unit is specifically configured to: determine that the third PDU session identifier is the same as the first PDU session identifier.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first preset value is determined according to the first access technology, the second preset value is determined according to the first preset value, The second preset value is different from the first preset value.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first access technology is a 3GPP access technology.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the second core network device is a mobility management entity (MME).

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first preset value is 64.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first access technology is an N3GPP access technology.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the second core network device is an evolved packet data gateway ePDG.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first preset value is 80.

With reference to the eighth aspect, in some implementation manners of the eighth aspect, the first core network device is a session management function SMF/packet data network gateway-control plane PGW-C network element.

In a ninth aspect, a communication device is provided, including: at least one processor, the at least one processor is coupled to at least one memory, and the at least one processor is configured to execute a computer program or an instruction stored in the at least one memory, so that The communication device executes any one of the above first method to the fourth aspect or a method in any possible implementation manner of the first method to the fourth aspect.

In a tenth aspect, a computer-readable storage medium is provided, where a computer program or an instruction is stored on the computer-readable storage medium, and when the computer program or instruction is run on a computer, the computer is made to perform the first method to the first method above. A method in any one of the four aspects or any possible implementation of the first method to the fourth aspect.

In an eleventh aspect, a chip system is provided, including: a processor configured to execute a computer program or an instruction in a memory, so as to implement any one of the above-mentioned first method to the fourth aspect or the first method to the first method A method in any possible implementation manner in the four aspects.

In a twelfth aspect, a computer program product is provided, including a computer program or an instruction. When the computer program or instruction is executed, any one of the above-mentioned first method to the fourth aspect or the first method to the fourth aspect A method in any one possible implementation of the aspect is performed.

A thirteenth aspect provides a communication system, including: the fifth aspect or the unit in any possible implementation of the fifth aspect; and/or, the unit in the sixth aspect; and/or the seventh aspect unit in .

Description of drawings

Fig. 1 is a schematic diagram of an application scenario applicable to the method provided by the embodiment of the present application.

FIG. 2 is a schematic diagram of a network architecture for 5G and 4G interaction provided by this application.

FIG. 3 is a schematic diagram of a network architecture for the interaction between the 3GPP access technology and the N3GPP access technology provided in the present application.

FIG. 4 is a schematic flowchart of a communication method provided by an embodiment of the present application.

FIG. 5 is another schematic flowchart of a communication method provided by an embodiment of the present application.

Fig. 6 is another schematic flowchart of a communication method provided by an embodiment of the present application.

FIG. 7 is another schematic flowchart of a communication method provided by an embodiment of the present application.

FIG. 8 is another schematic flowchart of a communication method provided by an embodiment of the present application.

FIG. 9 is another schematic flowchart of a communication method provided by an embodiment of the present application.

Fig. 10 is a schematic block diagram of a communication device provided by the present application.

Fig. 11 is a structural block diagram of a communication device provided according to an embodiment of the present application.

Detailed ways

The technical solution in this application will be described below with reference to the accompanying drawings.

The technical solution of the embodiment of the present application can be applied to various communication systems, for example: long term evolution (long term evolution, LTE) system, LTE frequency division duplex (frequency division duplex, FDD) system, LTE time division duplex (time division duplex) , TDD), worldwide interoperability for microwave access (WiMAX) communication system, fifth generation (5th generation, 5G) communication system or future communication system, for example, sixth generation (6th generation, 6G) communication system , vehicle-to-x (V2X), where V2X can include vehicle-to-network (V2N), vehicle-to-vehicle (V2V), vehicle-to-infrastructure ( vehicle-to-infrastructure (V2I), vehicle-to-pedestrian (V2P), etc., long term evolution-vehicle (LTE-V), vehicle networking, machine type communication (machine type communication) , MTC), Internet of Things (IoT), long term evolution-machine (LTE-M), machine to machine (M2M), etc.

In order to facilitate understanding of the embodiments of the present application, terms involved in the present application are explained first.

1. Protocol data network (protocol data network, PDN) connection (connection or connectivity)

A PDN connection refers to a combination of a group of evolved packet system (envolved packet system, EPS) bearers (bearers) established on the UE in the 4G communication system. These EPS bearers have the same Internet Protocol (Internet Protocol, IP) address and interface. The access point name (access point name, APN), the function of the PDN connection is to realize IP connectivity, and transmit the service data flow (service data flow, SDF) between the UE and the APN.

2. EPS bearer

EPS bearer (EPS Bearer) is a smaller tunnel included in the PDN connection, which refers to the data transmission channel in the 4G communication system. Specifically, the data transmitted in the same PDN connection will be treated differently by the EPS system during forwarding processing. In the same PDN connection, different EPS bearers represent different QoS, that is, different quality of service.

When a PDN connection is established, an EPS bearer will be established at the same time, which is called the default bearer (default bearer). The life cycle of the default bearer is the same as that of the PDN connection, and releasing the default bearer is equivalent to releasing the PDN connection. Dedicated bearer (dedicated bearer) refers to the bearer established to meet specific quality of service (quality of service, QoS) requirements after the establishment of the PDN connection. There may or may not be a dedicated bearer.

A UE may have multiple PDN connections, and a PDN connection may have multiple EPS bearers. The EPS bearer identity (EPS bearer identity, EBI) is used to distinguish multiple EPS bearers of the same UE, and the EBI of different UEs may be repeated. The length of the EBI is 4 bits, and the value range is 0 to 15. Among them, the value 0 to 4 is currently reserved, and the available value range is 5 to 15.

3. Protocol data unit (protocol data unit, PDU) session (PDU session)

In the 5G communication system, a group of QoS flows (flow) established on the UE are combined, and these QoS flows have the same IP address and Data Network Name (Data Network Name, DNN). QoS flow refers to the data transmission channel in the 5G communication system.

The 5G core network (5G core network, 5GC) supports PDU connection services. The PDU connection service may refer to a service for exchanging PDU data packets between a terminal device and a data network (data network, DN). The PDU connection service is realized by the establishment of the PDU session initiated by the terminal device. After a PDU session is established, that is, a PDU session tunnel is established. The PDU session tunnel corresponds to the UE, and the service data in the PDU session tunnel can be transmitted in the form of unicast QoS flow. In other words, PDU sessions are at UE level. Each end device can establish one or more PDU sessions. Wherein, the PDU session identifier (PduSessionId) can be used to distinguish different PDU sessions of the same UE.

The communication system applicable to the embodiment of the present application will be described in detail below with reference to FIG. 1 to FIG. 3 .

FIG. 1 is a schematic diagram of a network architecture applicable to the method provided by the embodiment of the present application. Figure 1 shows a schematic diagram of a 5G network architecture based on a service-oriented interface. The network architecture may specifically include the following network elements:

1. User equipment (UE) 110: may include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, computing devices or other processing devices connected to wireless modems, as well as various forms of terminals, Mobile station (mobile station, MS), terminal (terminal) or soft terminal, etc. For example, water meters, electricity meters, sensors, etc.

Exemplarily, the user equipment in this embodiment of the present application may refer to an access terminal, a subscriber unit, a user station, a mobile station, a mobile station, a relay station, a remote station, a remote terminal, a mobile device, a user terminal (user terminal), a terminal device (terminal equipment), wireless communication equipment, user agent or user device. The user equipment can also 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 wireless communication Functional handheld devices, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, user equipment in 5G networks or users in future evolved public land mobile networks (PLMN) Devices or user equipment in the future Internet of Vehicles, etc., are not limited in this embodiment of the present application.

As an example and not a limitation, in this embodiment of the application, wearable devices can also be referred to as wearable smart devices, which is a general term for intelligently designing daily wear and developing wearable devices by applying wearable technology, such as glasses, Gloves, watches, clothing and shoes, etc. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not only a hardware device, but also achieve powerful functions through software support, data interaction, and cloud interaction. Generalized wearable smart devices include full-featured, large-sized, complete or partial functions without relying on smart phones, such as smart watches or smart glasses, etc., and only focus on a certain type of application functions, and need to cooperate with other devices such as smart phones Use, such as various smart bracelets and smart jewelry for physical sign monitoring.

In addition, in the embodiment of the present application, the user equipment can also be the user equipment in the Internet of Things (Internet of Things, IoT) system. IoT is an important part of the development of information technology in the future, and its main technical feature is that items can be Connect with the network to realize the intelligent network of man-machine interconnection and object interconnection. In the embodiment of the present application, the IOT technology can achieve massive connections, deep coverage, and terminal power saving through, for example, narrow band (NB) technology. In addition, in this embodiment of the application, the user equipment may also include sensors such as smart printers, train detectors, and gas stations, and its main functions include collecting data (part of user equipment), receiving control information and downlink data of access network equipment, and Send electromagnetic waves to transmit uplink data to access network equipment.

2. (wireless) access network equipment (radio access network, (R)AN) 120: used to provide network access functions for authorized user equipment in a specific area.

Terminal devices can use access networks of different access technologies to access the core network, for example: using third generation partnership project (3rd generation partnership project, 3GPP) technology and non-3rd generation partnership project (non-3rd generation partnership project) technology , N3GPP) technology to access the core network. As an example but not a limitation, the access technology may include, for example, NR, evolved Universal Mobile Telecommunications System (Universal Mobile Telecommunications System, UMTS) Terrestrial Radio Access Network (UMTS Terrestrial Radio Access Network, E-UTRAN), Multefire, 3GPP access technology, N3GPP access technology, 4G cellular access technology, 5G cellular access technology, trusted or untrusted wireless fidelity (WiFi) access technology, fixed network or wired access technology, etc. In this regard, there is no limitation.

Among them, the access network using N3GPP technology may include but not limited to: wireless fidelity (wireless fidelity, Wi-Fi) system, wireless local area network (wireless local area network, WLAN), MulteFire network, wired network (for example: wireless and Wired convergence (wireless and wireline convergence, WWC) network), or femtocell network. Correspondingly, the access network equipment adopting the N3GPP technology may include, for example: an access point (access point, AP), a trusted WLAN interworking function (trusted WLAN interworking function, TWIF) network element, a trusted non-3GPP gateway function (trusted non-3GPP gateway function (TNGF), wired access gateway function (wireline access gateway function, W-AGF), access gateway function (access gateway function, AGF), broadband network gateway (broadband network gateway, BNG), fixed mobile Internet Operation function (fixed-mobile interworking function, FMIF), non-3GPP interworking function (Non-3GPP interworking function, N3IWF), etc.

The access network using 3GPP technology may include but not limited to: LTE network, NR network, 5G network, or subsequent evolution of mobile communication networks. Correspondingly, the access network equipment using the 3GPP technology may include, for example, radio access network (radio access network, RAN) equipment, g-NodeB, e-NodeB, and home-NodeB.

An access network that implements access network functions based on wireless communication technologies may be called a RAN. The radio access network can be responsible for functions such as radio resource management, quality of service (QoS) management, data compression and encryption on the air interface side. The wireless access network provides access services for terminal equipment, and then completes the forwarding of control signals and user data between the terminal and the core network.

Radio access network equipment may include, but not limited to, for example: a macro base station, a micro base station (also called a small station), a radio network controller (radio network controller, RNC), a node B (Node B, NB), a base station controller ( base station controller, BSC), base transceiver station (base transceiver station, BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (baseband unit, BBU), AP in the WiFi system, Wireless relay node, wireless backhaul node, transmission point (transmission point, TP) or transmission and reception point (transmission and reception point, TRP), etc., can also be gNB or transmission point (TRP) in the 5G (eg, NR) system or TP), one or a group (including multiple antenna panels) antenna panels of the base station in the 5G system, or, it can also be a network node that constitutes a gNB or a transmission point, such as a baseband unit (BBU), or, a distributed unit (distributed unit, DU), or the base station in the next-generation communication 6G system, etc. The embodiment of the present application does not limit the specific technology and specific equipment form adopted by the radio access network equipment.

The access network can provide services for the cells. The terminal device can communicate with the cell through the transmission resources (for example, frequency domain resources, or spectrum resources) allocated by the access network device.

3. User plane network element 130: used for packet routing and forwarding, and user plane data quality of service (quality of service, QoS) processing, etc.

In a 5G communication system, the user plane network element may be a user plane function (user plane function, UPF) network element. In the future communication system, the user plane network element may still be a UPF network element, or may have other names, which are not limited in this application.

4. Data network 140: used to provide a network for transmitting data.

In a 5G communication system, the data network may be a data network (data network, DN). In future communication systems, the data network may still be a DN, or may have other names, which are not limited in this application.

5. Access management network element 150: mainly used for mobility management and access management, etc., and can be used to implement functions other than session management in mobility management entity (mobility management entity, MME) functions, for example, access Access authorization/authentication and other functions.

In a 5G communication system, the access management network element may be an access and mobility management function (access and mobility management function, AMF) network element. In the future communication system, the access management network element may still be an AMF network element, or may have other names, which are not limited in this application.

6. Session management network element 160: mainly used for session management, network interconnection protocol (internet protocol, IP) address allocation and management of terminal equipment, selection of manageable user plane functions, termination points of policy control and charging function interfaces, and downlink Data Notification etc.

In a 5G communication system, the session management network element may be a session management function (session management function, SMF) network element. In the future communication system, the session management network element may still be an SMF network element, or may have other names, which are not limited in this application.

7. Policy control network element 170: a unified policy framework for guiding network behavior, providing policy rule information, etc. for network network elements (such as AMF, SMF network elements, etc.) or terminal devices.

In the 4G communication system, the policy control network element may be a policy and charging rules function (policy and charging rules function, PCRF) network element. In a 5G communication system, the policy control network element may be a policy control function (policy control function, PCF) network element. In the future communication system, the policy control network element may still be a PCF network element, or may have other names, which are not limited in this application.

8. Charging network element 180: as a quota control node for online charging, it performs rate processing for online charging for various services of user equipment.

In the 4G communication system, the charging network element may be an online charging system (online charging system, OCS) server or an online control and charging gateway (online control and charging gateway, OCG). In a 5G communication system, the charging network element may be a charging function (charging function, CHF) network element. In the future communication system, the billing network element may still be a CHF network element, or may have other names, which are not limited in this application.

9. Network opening network element 190: mainly used to support the opening of capabilities and events.

In a 5G communication system, the network exposure may be a network exposure function (network exposure function, NEF) network element. In the future communication system, the open network element may still be an NEF network element, or may have other names, which are not limited in this application.

10. Data management network element 1100: used for processing terminal equipment identification, access authentication, registration and mobility management, etc.

In a 5G communication system, the data management network element may be a unified data management (unified data management, UDM) network element. In the future communication system, the unified data management may still be a UDM network element, or may have other names, which are not limited in this application.

11. Application network element 1110: used for routing data affected by applications, accessing network elements with open network functions, and interacting with policy frameworks for policy control, etc.

In a 5G communication system, the application network element may be an application function (application function, AF) network element. In the future communication system, the application network element may still be an AF network element, or may have other names, which are not limited in this application.

12. Data analysis network element 1120: used to implement a network data analysis function.

The data analysis network element can be a single network element, or a combination of multiple network elements, or be co-located with other network elements. For example, the NWDAF network element may be co-configured with the AMF or with the session management function (session management function, SMF) network element.

In a 5G communication system, the data analysis network element may be a network data analysis function (network data analytics function, NWDAF) network element. In the future communication system, the data analysis network element may still be the NWDAF network element, or may have other names, which are not limited in this application.

13. Network slice selection network element 1130: used to select a network slice instance serving the user equipment.

In a 5G communication system, the network slice selection network element may be a network slice selection function (network slice selection function, NSSF) network element. In the future communication system, the network element with network slice selection function may still be an NSSF network element, or may have other names, which are not limited in this application.

It can be understood that the above-mentioned network element or function may be a network element in a hardware device, or a software function running on dedicated hardware, or a virtualization function instantiated on a platform (for example, a cloud platform).

For the convenience of description, in the follow-up of this application, the network element with the access management function is the AMF network element, the network element with the data analysis function is the NWDAF network element, and the network element with the policy control function is the PCF network element.

Further, the AMF network element is referred to as AMF, the NWDAF network element is referred to as NWDAF, and the PCF network element is referred to as PCF. That is, the AMF described later in this application can be replaced by an access management function network element, the NWDAF can be replaced by a data analysis function network element, and the PCF can be replaced by a policy control function network element.

For the convenience of description, this application takes the device as an example of an AMF entity, an NWDAF entity, and a PCF entity to describe the method for obtaining data. For a device that is a chip in an AMF entity, a chip in an NWDAF entity, or a PCF entity For the implementation method of the chip, refer to the specific descriptions of the devices being the AMF entity, the NWDAF entity, and the PCF entity, and the introduction will not be repeated.

In the network architecture shown in Figure 1, the terminal device is connected to the AMF through the N1 interface, the RAN is connected to the AMF through the N2 interface, and the RAN is connected to the UPF through the N3 interface. The UPFs are connected through the N9 interface, and the UPF is interconnected with the data network (data network, DN) through the N6 interface. The SMF controls the UPF through the N4 interface. NSSF accesses the service architecture through the Nnssf interface and provides corresponding services. Similarly, CHF, PCF, UDM, NWDAF, and AF access the service architecture through their corresponding interfaces to provide corresponding services. In Figure 1, Nnef, Nchf, Npcf, Nudm, Nnwdaf, Naf, Namf, Nsmf, Nnssf, N1, N2, N3, N4, and N6 are interface serial numbers. The meanings of these interface serial numbers may refer to the meanings defined in the third generation partnership project (3rd generation partnership project, 3GPP) standard agreement, and no limitation is made here.

It should be noted that the names of the various network elements involved in Figure 1 and the communication interfaces between the network elements are simply described using the current protocol as an example, but this does not limit that the embodiment of the present application can only be applied to currently known communication systems. Therefore, the standard names that appear when describing the current protocol as an example are all functional descriptions. This application does not limit the specific names of network elements, interfaces, or signaling, but only indicates the functions of network elements, interfaces, or signaling. It can be correspondingly extended to other systems, such as 2G, 3G, 4G or future communication systems.

In addition, it should be noted that in some network architectures, network function network element entities such as AMF network elements, SMF network elements, PCF network elements, BSF network elements, and UDM network elements are called network function network elements (network function network elements). , NF) network elements; or, in other network architectures, a collection of network elements such as AMF network elements, SMF network elements, PCF network elements, BSF network elements, and UDM network elements can be called control plane function network elements.

The following briefly introduces the interaction between 5G and 4G with reference to FIG. 2 . FIG. 2 is a schematic diagram of a network architecture for interaction between 5G and 4G provided by this application.

In Fig. 2, the home subscriber server (home subscriber server, HSS) is a server in the 4G network for storing user subscription information, and the serving gateway (serving gateway, SGW) is the user plane access serving gateway in the 4G network. The packet data network gateway-control plane (packet data network gateway control, PGW-C) network element and the packet data network gateway-user plane (packet data network gateway user, PGW-U) network element are responsible user equipment in the 4G network The network element connected to the external network also undertakes the session management and bearer control of the mobile phone, as well as IP address allocation, billing support and other functions. Evolved UMTS terrestrial radio access network (evolved UMTS terrestrial radio access network, E-UTRAN) is the access network equipment in the 4G network. UE can access the 4G core network equipment through E-UTRAN, and NG-RAN is the 5G network equipment. The access network equipment, UE can access the 5G core network equipment through NG-RAN. The MME is a 4G core network device, responsible for authentication, authorization, mobility management, and session management of the UE. The EPS bearer identify (EBI) of the UE's 4G PDN connection is allocated by the device.

It can be seen from Figure 2 that the 5G network is co-configured with 4G network elements (as shown in Figure 2, SMF and PGW-C, UDM and HSS, etc.) The N26 interface is opened between the AMF shown in 2 and the MME) to realize the interaction between the two networks.

For example: UDM/HSS is the core network equipment shared by 4G and 5G, that is, the core network equipment jointly established by 4G and 5G, including HSS and UDM, can provide at least one of the following functions for terminal equipment: processing 3GPP AKA authentication credentials, user identification processing, access authorization, registration/mobility management, subscription management and SMS management, etc. SMF/PGW-C is the core network equipment jointly established by 4G and 5G, including the functions of SMF and PGW-C. UPF/PGW-U is the core network equipment jointly established by 4G and 5G, including the functions of SMF and PGW-C.

It should be noted that each interface name shown in Figure 2 (for example, S1-MME, S1-U, S11, N26, N3, N1, N2, N11, S11, S5-U, S5 -C, N15, N7, N8, N10, S6a, N40) are just examples and do not constitute any limitation to the scope of protection of this application. For the meaning of these interface serial numbers, please refer to the meaning defined in the standard protocol.

In the embodiment of the present application, the user equipment or the access network equipment includes a hardware layer, an operating system layer running on the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also called main memory). The operating system may be any one or more computer operating systems that implement business processing through processes, for example, Linux operating system, Unix operating system, Android operating system, iOS operating system, or windows operating system. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software. Moreover, the embodiment of the present application does not specifically limit the specific structure of the execution subject of the method provided by the embodiment of the present application, as long as the program that records the code of the method provided by the embodiment of the present application can be run to provide the method according to the embodiment of the present application. For example, the execution subject of the method provided in the embodiment of the present application may be a user equipment or an access network device, or a functional module in the user equipment or access network device that can call a program and execute the program.

The following briefly introduces the 3GPP access technology and the N3GPP access technology with reference to FIG. 3 . FIG. 3 is a schematic diagram of a network architecture for interaction between the 3GPP access technology and the N3GPP access technology provided in this application.

The architecture shown in FIG. 3 includes 3GPP and N3GPP system architectures, which are divided by a dotted line 301 . Above the line 301 is the 3GPP access network, and below the dotted line 301 is the N3GPP access network. UE, E-UTRAN, MME, HSS, CHF, PCF, SMF/PGW-C in Figure 3 have similar or same functions as those in Figure 1 and Figure 2 . The operator's IP service may include an IP Multimedia Service Subsystem (IP Multimedia Subsystem, IMS). In the N3GPP access technology, the terminal device can establish a connection with the SMF/PGW-C through the evolved packet data gateway (ePDG), and the SMF/PGW-C provides the related services of the session-related control plane. The EPS bearer identifier (EPS bearer identify, EBI) of the PDN connection of the UE in the N3GPP access is allocated by the device.

The respective interface names shown in Figure 3 (for example, S5, S11, S2a, S2b, SWu, SWn, SWa, STa, SWm, S6b, SGi, Rx, SWx shown in Figure 2) are examples only, and these interface sequences For the meaning of the number, please refer to the meaning defined in the standard agreement, and this application does not limit its name and meaning.

When a terminal device needs to create a session, if the terminal device has 4G and 5G interoperability, the PDU identifier is allocated by the terminal device and carried to the network side. If the terminal device does not have 4G and 5G interoperability, the terminal device will not carry the PDU session identifier. According to the provisions of the protocol TS 29.571, the PDU session identifier is assigned by the SMF/PGW-C network element according to the EPS bearer identifier EBI assigned by the MME or ePDG. Responsible for generation. The specific generation principle is: for the session in the 3GPP access network, the SMF/PGW-C network element adds 64 to the default bearer identifier assigned by the MME; for the N3GPP access network, the SMF/PGW-C network element Add 80 to the default bearer identifier allocated by the ePDG.

For a terminal device that does not have the interoperability between 4G and 5G, if it switches between the 3GPP access network and the N3GPP access network, the first PDU session created by it will also switch. However, in the existing protocol, the co-located SMF/PGW-C network element does not update the first PDU session identifier to the policy control function (policy control function, PCF) network element and/or the charging function (charging function, CHF) ) network element. In this way, when a terminal device creates a second PDU session, two identical PDU session identifiers may appear for the same terminal device on the PCF network element and/or CHF network element, which may be considered as duplication of the same service In the activated scenario, the services corresponding to the two PDU sessions cannot be performed at the same time.

For example, if a terminal device #A that does not have 4G and 5G interoperability initially initiates access through the 3GPP access network and creates session #1, the MME assigns EBI to session #1 as 5. According to the above, the SMF/PGW-C network element will generate the PDU session identifier 69 (ie 5+64) for session #1, and the SMF/PGW-C will generate the PDU through the N7 and N40 interfaces in Figure 2 and Figure 3 respectively. The PDU session identifier 69 of the session #1 is sent to the PCF and the CHF, and the PCF and the CHF complete the policy rule guidance and charging processing of the session #1. When terminal device #A undergoes a mobility handover from the initially accessed 3GPP access network to the N3GPP access network, session #1 will also be switched to the N3GPP access network, the MME will release the EBI of session #1, and the ePDG will Reassign EBI for session #1, probably still at 5. Since it is only a switching process, the N7 interface and the N40 interface send update messages. In the existing protocol, the update message of the N7 interface between SMF/PGW-C and PCF does not support carrying the PDU session identifier, so the update message sent to the PCF will not carry the PDU session identifier, that is, the PCF side stores the session #1 The ID is still 69. Although the update message of the N40 interface between SMF/PGW-C and CHF supports carrying the PDU session identifier, the existing protocol does not define the specific processing method of the N40 interface in the case of handover, so the CHF cannot update the PDU session identifier in time.

When terminal device #A initiates access through the 3GPP access network again and creates session #2, since the EBI of session #1 has been released, the EBI allocated by MME for session #2 may still be 5. According to the above, the SMF/PGW-C network element will generate a PDU session identifier 69 (ie 5+64) for session #1. Similarly, the SMF/PGW-C will pass through the N7 and N40 interfaces in Figure 2 and Figure 3 The generated PDU session identifier 69 of session #2 is sent to PCF and CHF respectively, and the PCF and CHF complete the policy rule guidance and charging processing of session #2.

In this case, there will be two session IDs of 69 on PCF and CHF on terminal device #A. This situation may be considered as a scenario where the same service is repeatedly activated. In one possible way, PCF The previously saved session with the ID of 69 will be deleted, and the new session with the ID of 69 will be successfully accessed. In one possible way, the PCF will continue to use the previously saved session with the ID of 69, and delete the new session with the ID of 69 sessions, but no matter which way, the services corresponding to session #1 and session #2 cannot be performed at the same time, affecting user experience.

In view of this, the present application provides a communication method and a communication device, so that multiple services of a terminal device can be performed simultaneously, thereby improving user experience.

FIG. 4 is a schematic flowchart of a communication method provided by an embodiment of the present application. The method 400 shown in FIG. 4 may be executed by any communication system in FIG. 1 to FIG. 3 .

S410, the second core network device sends a first request message, and correspondingly, the first core network device receives the first request message, where the first request message is used to request that the first session of the terminal device be switched from the first access technology to the second access technology Two access technologies, the first request message includes the first evolved packet system bearer identifier EBI of the first session.

When the first session of the terminal device needs to be switched from the first access technology to the second access technology, the second core network device will send a first request message to the first core network device, and the first request message includes the first session Session ID, that is, the first EBI.

In one implementation, the first request message may be a session creation request (create session request) message, the session creation request message includes a handover indication (handover indication, HI) flag, and the handover indication flag is used to indicate the terminal device Whether the first session is a switched session, for example, the switching indication flag may indicate that the first session of the terminal device is a switched session, that is, the first session of the terminal device needs to be switched from the first access technology to the second access technology, The first core network device may analyze the information of the handover indication flag bit, so as to determine that the first session of the first terminal device has been handed over.

It should be understood that in this application, the first session of the terminal device may be a switched session or an initially established session. In method 400, the first session is a switched session.

S420, the first core network device sends an update message to the third core network device, where the update message includes a first PDU session identifier, and the first PDU session identifier is generated according to the first EBI and a first preset value. Correspondingly, the third core network device receives the update message. Wherein, the third core network device is a network element with a policy control function and/or a network element with a charging function.

After receiving the first request message, the first core network device will send an update message to the policy control function network element and/or the charging function network element respectively, for example, the update message may be an update request (update request) message, the update The message carries the first PDU session identify (PDU session identify) generated according to the first EBI and the first preset value. In other words, the first core network device can convert the first EBI identifying the first session into the first PDU session An identifier, the first session is identified by the first PDU session identifier, and the first PDU session identifier is carried in an update message sent to the policy control function network element and/or the charging function network element.

In view of this, in this embodiment of the application, when the first session of the terminal device needs to be switched from the first access technology to the second access technology, the second core network device will send a first request message, and the first core network device After receiving the first request message, an update message is sent to the policy control function network element and/or the charging function network element respectively, and the update message carries the first PDU session identifier generated according to the first EBI. In other words, this application carries the first PDU session identifier in the update message, so that the policy control function network element and/or the charging function network element can update the PDU session identifier of the first session in time, avoiding the session identifier of the session established later Repeat, so that multiple services of the terminal device can be performed at the same time, improving user experience.

It should be understood that in S420, according to actual application conditions, the update message may be sent only to the network element with the policy control function, or the update message may be sent only to the network element with the charging function, or the update message may be sent to the network element with the policy control function and the network element with the charging function Updates are sent. In addition, when the first core network device sends an update message to both the policy control function network element and the charging function network element, the sequence of sending the update message to the policy control function network element and the charging function network element does not change. limited, it can be sent to the network element with the policy control function first, or it can be sent to the network element with the charging function first.

In an implementation manner, the first core network device is an SMF/PGW-C.

Optionally, the method 400 further includes: S430, the first core network device generates a first PDU session identifier according to the first EBI and a first preset value.

The first core network device may generate the first PDU session identifier according to the first EBI and the first preset value, that is, the first core network device may convert the first EBI identifying the first session into the first PDU session identifier, and pass the first The PDU session identifier is used to identify the first session. Wherein, the first preset value depends on the PDU session generation rule defined in the protocol.

In an implementation manner, the first preset value is determined according to the second access technology.

In an implementation manner, the first access technology is a 3GPP access technology, and the second access technology is an N3GPP access technology.

That is, the first session of the terminal device is switched from the 3GPP access technology to the N3GPP access technology.

In an implementation manner, the first access technology is a 3GPP access technology, the second access technology is an N3GPP access technology, and the second core network device is an ePDG.

When the first session of the terminal device is switched from the 3GPP access technology to the N3GPP access technology, the ePDG in the N3GPP access network will allocate the first EBI for the first session after switching, and the ePDG will send the first EBI to the first core network device. A request message.

In an implementation manner, the first access technology is a 3GPP access technology, the second access technology is an N3GPP access technology, and the first preset value is 80.

That is to say, the first core network device generates the first PDU session identifier according to the switched access technology, that is, the generation rule of the PDU session identifier in the N3GPP access technology. It is stipulated in the protocol TS 29.571 that for the access network using N3GPP technology, the SMF/PGW-C network element adds 80 to the default bearer identifier assigned by ePDG, that is, the first default value is 80.

In an implementation manner, the first access technology is an N3GPP access technology, and the second access technology is a 3GPP access technology.

That is, the first session of the terminal device is switched from the N3GPP access technology to the 3GPP access technology.

In an implementation manner, the first access technology is an N3GPP access technology, the second access technology is a 3GPP access technology, and the second core network device is an MME.

When the first session of the terminal device is switched from the N3GPP access technology to the 3GPP access technology, the MME in the 3GPP access network will allocate the first EBI for the first session after the switch, and the MME will send the first EBI to the first core network device. A request message.

It should be understood that when the MME sends the first request message to the first core network device, the MME may first send it to the SGW, and then the SGW sends it to the first core network device.

In an implementation manner, the first access technology is an N3GPP access technology, the second access technology is a 3GPP access technology, and the first preset value is 64.

That is to say, the first core network device generates the first PDU session identifier according to the switched access technology, that is, the generation rule of the PDU session identifier in the 3GPP access technology. It is stipulated in the protocol TS 29.571 that for the access network using 3GPP technology, the SMF/PGW-C network element adds 64 to the default bearer identifier assigned by the MME, that is, the first preset value is 64.

In an implementation manner, the method 400 further includes: S440, the third core network device stores the mapping relationship between the identifier of the terminal device and the first PDU session identifier.

The policy control network element and/or the charging function network element may save the mapping relationship between the identifier of the terminal device and the first PDU session identifier, so as to manage the first session of the terminal device through the first PDU session identifier.

Optionally, the identifier of the terminal device may be an international mobile subscriber identity (IMSI), which is used to identify different terminal devices.

In a possible implementation manner, the terminal device does not have the interoperability between 4G and 5G.

That is, for a terminal device that does not have the interoperability between 4G and 5G, it will not carry the PDU session identifier.

The specific implementation of the communication method 400 provided by the present application will be described below with reference to FIG. 5 . FIG. 5 is another schematic flowchart of a communication method provided by an embodiment of the present application. It should be understood that, in the method 500 in FIG. 5 , the first access technology in the method 400 is the 3GPP access technology, and the second access technology is the N3GPP access technology as an example for illustration.

S501. When the terminal device initiates the session #1 through the 3GPP access technology, the core network device initiates the creation process of the session #1 through the 3GPP technology. At this time, the MME sends the creation request of the session #1 to the SMF/PGW-C through the SGW Message #1, which includes EBI #1 for identifying session #1. For example, the value of EBI#1 is 5.

Optionally, the message #1 may include an HI flag bit, for example, the value of this field is 0, indicating that the session #1 of the terminal device is an initially established session.

For example, session #1 is a voice service, and the form of the creation request message #1 of session #1 may be: Create Session Request (APN=voice, EBI=5).

Specifically, the EBI in message #1 may refer to a default bearer identifier (linked bearer identify, LBI), which is referred to as EBI for short in this application.

S502. The SMF/PGW-C generates a PDU session identifier #1 according to the EBI #1.

Since the session #1 is a session initiated through the 3GPP access technology, the SMF/PGW-C generates the PDU session identifier #1 according to the first preset value of 64 according to the protocol. For example, the generated token #1 is 5+64=69.

S503, the SMF/PGW-C sends a create request (create request) message #2 to the CHF, and the message #2 includes the identifier #1.

SMF/PGW-C can send creation request message #2 to CHF through N40 interface.

For example, the form of the create request message #2 may be: Nchf_ConvergedCharging_Create Requestet (PduSessionId1=5+64=69, ChargingId1=ChargingIdA).

S504. The CHF saves the mapping relationship between the identifier of the terminal device and the identifier #1.

For example, the identifier of the terminal device is IMSI#1, and the CHF stores the mapping relationship #1 between IMSI#1 and identifier #1.

S505, the SMF/PGW-C sends a creation request message #3 to the PCF, and the message #3 includes the identifier #1.

SMF/PGW-C can send creation request message #3 to PCF through N7 interface.

For example, the form of the create request message #3 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId1=5+64=69).

It should be understood that the sending order of message #2 and message #3 is not limited, that is, the order of S503 and S504 is not limited.

S506. The PCF saves the mapping relationship between the identifier of the terminal device and the identifier #1.

For example, the identifier of the terminal device is IMSI#1, and the PCF stores the mapping relationship #2 between the IMSI#1 and the identifier #1.

S507. When the mobility handover of the terminal equipment occurs, the 3GPP technical access network is switched to the N3GPP technical access network, and the session #1 will be switched to the N3GPP technical access network. At this time, the ePDG will send the session to the SMF/PGW-C Create request message #4 of #1, message #4 includes EBI #2 reallocated by ePDG. Since EBI #2 and EBI #1 are allocated by different network elements, it may happen that the allocated EBI values are the same. For example, the value of EBI#2 is 5.

Message #4 also includes an HI flag bit, for example, if this field takes a value of 1, it indicates that session #1 of the terminal device is a handover session. Or it can also be understood as indicating that the session #1 of the terminal device is switched from the 3GPP access technology to the N3GPP access technology.

For example, the form of the creation request message #4 of the session #1 may be: Create Session Request (EBI=5).

S508, SMF/PGW-C generates PDU session identifier #2 according to EBI #2.

Since the session #1 is switched to the N3GPP access technology, the SMF/PGW-C generates the PDU session identifier #2 according to the first preset value of 80 according to the agreement. For example, the generated token #2 is 5+80=85.

S509, the SMF/PGW-C sends an update request message #1 to the CHF, where the update request message #1 includes the identifier #2.

The SMF/PGW-C can send an update request message #1 to the CHF through the N40 interface.

For example, the format of the update request message #1 may be: Nchf_ConvergedCharging_Update Requestet (PduSessionId1=5+80=85, ChargingId1=ChargingIdA).

S510, the CHF updates the identity #1 according to the update request message #1, or, it can also be said, updates the mapping relationship #1.

For example, the CHF updates the mapping relationship #1 to the corresponding relationship between the IMSI #1 and the identifier #2 according to the identifier #2 in the update request message #1.

S511. The SMF/PGW-C sends an update request message #2 to the PCF, where the update request message #2 includes the identifier #2.

The SMF/PGW-C can send an update request message #2 to the PCF through the N7 interface.

For example, the format of the update request message #2 may be: Npcf_SMPolicyControl_Update Requestet(PduSessionId1=5+80=85).

S512. The PCF updates the identifier #1 according to the update request message #2, or, it can also be said, updates the mapping relationship #2.

For example, the PCF updates the mapping relationship #2 to the corresponding relationship between the IMSI #1 and the identifier #2 according to the identifier #2 in the update request message #1.

It should be understood that the sending order of the update request message #1 and the update request message #2 is not limited, that is, the sequence of S509 and S511 is not limited.

For example, when the session #1 is handed over to the N3GPP access technology, the method 500 further includes:

S513, the SMF/PGW-C sends a release message to the MME through the SGW, for example, a delete bearer request (delete bearer request) message, carrying the identifier of the session where the handover occurs, that is, EBI#1.

For example, the format of the delete bearer request message may be: Delete Bearer Request (EBI=5).

After receiving the release message, the MME will release the EBI#1 identifying the session #1.

S514, when the terminal device initiates the session #2 again through the 3GPP access technology, similar to S501 to S506, the core network device initiates the creation process of the session #2 through the 3GPP technology. At this time, the MME sends a creation request message #5 of the session #2 to the SMF/PGW-C through the SGW.

Similarly, message #5 may include EBI #3 allocated by MME for session #2, since in S513, EBI #1 generated by MME for session #1 has been released, so EBI #3 allocated by MME for session #2 may It will be the same as the EBI#1 assigned to session #1 before, for example, the value of EBI#3 is 5.

For example, session #2 is multimedia message service, and the form of creating request message #5 of session #2 can be: Create Session Request (APN=mms, EBI=5).

S515 to S519, SMF/PGW-C generates PDU session identifier #3 according to EBI#3, and sends identifier #3 to CHF and PCF through creation request message #6 and creation request message #7, so that CHF and PCF can save the terminal The correspondence between the device ID and ID #3.

For example, the form of the create request message #6 may be: Nchf_ConvergedCharging_Create Requestet(PduSessionId2=5+64=69, ChargingId2=ChargingIdB). The form of the create request message #7 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId2=5+64=69).

If EBI#1 and EBI#3 are the same, then the identity #1 and identity #3 are also the same, however, in CHF and PCF at this time, identity #3 is used to identify session #2 of the terminal device, while identifying session #1 The PDU session identifier of the PDU has been updated to identifier #2 in S507 to S512, and there will be no duplication. That is to say, through the method of this application, the policy control function network element and/or the charging function network element can update the PDU session identifier of the first session in time, avoiding duplication with the session identifier of the session established later, so that the terminal device Multiple services can be performed simultaneously to improve user experience.

The specific steps from S515 to S519 are similar to those from S502 to S506 and will not be repeated here.

It should be understood that the values of the HI flag bits in S501 and S507 are for illustration only, and are not limited in this application.

Another specific implementation of the communication method 400 provided by the present application will be described below with reference to FIG. 6 . Fig. 6 is another schematic flowchart of a communication method provided by an embodiment of the present application. It should be understood that in the method 600 in FIG. 6 , the first access technology in the method 400 is the N3GPP access technology, and the second access technology is the 3GPP access technology as an example for illustration.

S601. When the terminal device initiates session #1 through the N3GPP access technology, the core network device initiates the session #1 creation process through the N3GPP technology. At this time, the ePDG sends a session #1 creation request message to the SMF/PGW-C# 1. Message #1 includes EBI #1 for identifying session #1. For example, the value of EBI#1 is 6.

Optionally, the message #1 may include an HI flag bit, for example, if the value of this field is 0, it indicates that the session #1 of the terminal device is a new session.

For example, session #1 is a voice service, and the form of the creation request message #1 of session #1 may be: Create Session Request (APN=voice, EBI=6).

S602. The SMF/PGW-C generates a PDU session ID #1 according to the EBI #1.

Since the session #1 is a session initiated through the N3GPP access technology, the SMF/PGW-C generates the PDU session identifier #1 according to the first preset value of 80 according to the protocol. For example, the generated token #1 is 6+80=86.

S603, the SMF/PGW-C sends a creation request message #2 to the CHF, and the message #2 includes the identifier #1.

SMF/PGW-C can send creation request message #2 to CHF through N40 interface.

For example, the form of the create request message #2 may be: Nchf_ConvergedCharging_Create Requestet (PduSessionId1=6+80=86, ChargingId1=ChargingIdA).

S604, the CHF saves the mapping relationship between the identifier of the terminal device and the identifier #1.

S605, the SMF/PGW-C sends a creation request message #3 to the PCF, and the message #3 includes the identifier #1.

SMF/PGW-C can send creation request message #3 to PCF through N7 interface.

For example, the form of the create request message #3 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId1=6+80=86).

It should be understood that the sending order of message #2 and message #3 is not limited, that is, the order of S603 and S604 is not limited.

S606. The PCF stores the mapping relationship between the identifier of the terminal device and the identifier #1.

S607. When the mobility handover of the terminal equipment occurs, the N3GPP technical access network is switched to the 3GPP technical access network, and the session #1 will be switched to the 3GPP technical access network. At this time, the MME will communicate with the SMF/PGW-C through the SGW. The creation request message #4 of the session #1 is sent, and the message #4 includes the EBI #2 reallocated by the MME. Since EBI #2 and EBI #1 are allocated by different network elements, it may happen that the allocated EBI values are the same. For example, the value of EBI#2 is 6.

Message #4 also includes a HI flag bit. For example, if this field takes a value of 1, it indicates that session #1 of the terminal device is a session where handover occurs. Or it can also be understood as indicating that the session #1 of the terminal device is switched from the N3GPP access technology to the 3GPP access technology.

For example, the form of the creation request message #4 of the session #1 may be: Create Session Request (EBI=6).

S608, SMF/PGW-C generates PDU session ID #2 according to EBI #2.

Since the session #1 is switched to the 3GPP access technology, the SMF/PGW-C generates the PDU session identifier #2 according to the first preset value of 64 according to the protocol. For example, the generated token #2 is 6+64=70.

S609, the SMF/PGW-C sends an update request message #1 to the CHF, where the update request message #1 includes the identifier #2.

For example, the format of the update request message #1 may be: Nchf_ConvergedCharging_Update Requestet (PduSessionId1=6+64=70, ChargingId1=ChargingIdA).

S610, the CHF updates the identity #1 according to the update request message #1, or, it can also be said, updates the mapping relationship #1.

S611, the SMF/PGW-C sends an update request message #2 to the PCF, where the update request message #2 includes the identifier #2.

For example, the format of the update request message #2 may be: Npcf_SMPolicyControl_Update Requestet(PduSessionId1=6+64=70).

S612. The PCF updates the identity #1 according to the update request message #2, or, it can also be said, updates the mapping relationship #2.

It should be understood that the sending order of the update request message #1 and the update request message #2 is not limited, that is, the sequence of S609 and S611 is not limited.

In view of this, in this embodiment of the application, when the first session of the terminal device needs to be switched from the first access technology to the second access technology, the second core network device will send a first request message, and the first core network device After receiving the first request message, an update message will be sent to the policy control function network element and/or the charging function network element respectively, and the update message carries the first PDU session identifier generated according to the first EBI. In other words, this application carries the first PDU session identifier in the update message, so that the policy control function network element and/or the charging function network element can update the PDU session identifier of the first session in time, avoiding the session identifier of the session established later Repeat, so that multiple services of the terminal device can be performed at the same time, improving user experience.

For example, when session #1 is handed over to the 3GPP access technology, the method 600 further includes:

S613, the SMF/PGW-C sends a release message to the ePDG, for example, a delete bearer request (delete bearer request) message, carrying the identifier of the session where the handover occurs, that is, EBI#1.

For example, the format of the delete bearer request message may be: Delete Bearer Request (EBI=6).

S614, when the terminal device initiates the session #2 again through the N3GPP access technology, similar to S601 to S606, the core network device initiates the creation process of the session #2 through the N3GPP technology. At this point, the ePDG sends a session #2 creation request message #5 to the SMF/PGW-C.

Similarly, message #5 may include EBI #3 allocated by ePDG for session #2. Since EBI #1 generated by ePDG for session #1 has been released in S613, EBI #3 allocated by ePDG for session #2 may It will be the same as the EBI#1 assigned to session #1 before, for example, the value of EBI#3 is 6.

For example, session #2 is a multimedia message service, and the form of creating request message #5 of session #2 may be: Create Session Request (APN=mms, EBI=6).

From S615 to S619, SMF/PGW-C generates PDU session identifier #3 according to EBI#3, and sends identifier #3 to CHF and PCF through creation request message #6 and creation request message #7, so that CHF can save the terminal device's The mapping relationship #3 between the identifier and the identifier #3, and the PCF may save the mapping relationship #4 between the identifier of the terminal device and the identifier #3.

For example, the form of the create request message #6 may be: Nchf_ConvergedCharging_Create Requestet (PduSessionId2=6+80=86, ChargingId2=ChargingIdB). The form of the create request message #7 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId2=6+80=86).

If EBI#1 and EBI#3 are the same, then the identity #1 and identity #3 are also the same, however, in CHF and PCF at this time, identity #3 is used to identify session #2 of the terminal device, while identifying session #1 The PDU session identifier of the PDU has been updated to identifier #2 in S607 to S612, and there will be no duplication. That is to say, through the method of this application, the policy control function network element and/or the charging function network element can update the PDU session identifier of the first session in time, avoiding duplication with the session identifier of the session established later, so that the terminal device Multiple services can be performed simultaneously to improve user experience.

The specific steps from S615 to S619 are similar to those from S602 to S606 and will not be repeated here.

It should be understood that the values of the HI flag bits in S601 and S607 are for illustration only, and are not limited in this application.

Fig. 7 is a schematic flowchart of a communication method provided by an embodiment of the present application. The method 700 shown in FIG. 7 may be executed by any communication system in FIG. 1 to FIG. 3 .

S710. The second core network device sends a first request message. Correspondingly, the first core network device receives the first request message. The first request message is used to request to create a first session of the terminal device through the first access technology. The first request message includes a first EPS bearer identifier EBI of the first session.

When the terminal device needs to create a first session through the first access technology, the second core network device will send a first request message to the first core network device, and the first request message includes the session identifier of the first session, that is, the first EBI .

Optionally, the first request message may be a session creation request (create session request) message, the session creation request message includes a handover indication (handover indication, HI) flag, and the handover indication flag is used to indicate the first session of the terminal device Whether it is an initially established session, for example, the handover indication flag can indicate that the first session of the terminal device is an initially established session, that is, the terminal device needs to use the first access technology to create the first session, and the first core network device can resolve the handover Indicate the information of the flag bit, so as to determine that the first session of the first terminal device is an initially established session.

It should be understood that in this application, the first session of the terminal device may be a switched session or an initially established session. In method 700, the first session is an initially established session.

S720. When the first core network device determines that the first PDU session identifier is a duplicate identifier of the terminal device, send a creation message to the third core network device, where the creation message includes the second PDU session identifier, the second PDU session identifier and the first PDU session identifier. The PDU session identifiers are different, and the first PDU session identifier is generated according to the first EBI and the first preset value. Correspondingly, the third core network device receives the creation message. Wherein, the third core network device is a network element with a policy control function and/or a network element with a charging function.

After receiving the first request message, the first core network device will send creation messages to the policy control function network element and/or the charging function network element respectively when determining that the first PDU session identifier is a duplicate identifier of the terminal device, for example , the creation message may be a create request message, which carries a second PDU session identifier (PDU session identify), and the second PDU session identifier is different from the first PDU session identifier, wherein the first PDU session The identifier is generated according to the first EBI and the first preset value. In other words, the first core network device may convert the first EBI identifying the first session into a second PDU session ID different from the first PDU session ID, identify the first session by the second PDU session ID, and send the EBI to the policy The creation message of the control function network element and/or the charging function network element carries the second PDU session identifier.

In view of this, in the embodiment of the present application, when the terminal device needs to create the first session through the first access technology, the second core network device will send the first request message, and the first core network device will receive the first request message Afterwards, a creation message will be sent to the policy control function network element and/or the charging function network element respectively, the creation message carries the second PDU session identifier, and the second PDU session identifier is different from the first PDU session identifier, wherein, The first PDU session identifier is generated according to the first EBI and a first preset value. In other words, the present application carries the second PDU session identifier different from the first PDU session identifier in the creation message, so as to prevent the policy control function network element and/or the charging function network element from receiving the same PDU session identifier as the first session. Session identification, so that multiple services of the terminal device can be performed at the same time, improving user experience.

It should be understood that in S720, according to actual application conditions, the creation message may be sent only to the network element with the policy control function, or the creation message may be sent only to the network element with the charging function, or, the creation message may be sent to the network element with the policy control function and the network element with the charging function Both send create messages. In addition, when the first core network device sends the creation message to both the policy control function network element and the charging function network element, the order of sending the creation message to the policy control function network element and the charging function network element does not change. limited, it can be sent to the network element with the policy control function first, or it can be sent to the network element with the charging function first.

In an implementation manner, the first core network device is an SMF/PGW-C.

Optionally, the method 700 further includes: S730, the first core network device generates a first PDU session identifier according to the first EBI and a first preset value, and generates a second PDU session identifier according to the first EBI and a second preset value , wherein the second preset value is different from the first preset value.

The first core network device may first generate the first PDU session identifier according to the first EBI and the first preset value, and select a second PDU session identifier different from the first preset value when determining that the first PDU session identifier is a duplicate identifier of the terminal device. A preset value, generating a second PDU session identifier according to the first EBI and a second preset value. That is, the first core network device may convert the first EBI identifying the first session into a second PDU session ID different from the first PDU session ID, and use the second PDU session ID to identify the first session. Wherein, the first preset value depends on the PDU session generation rule defined in the protocol. The second preset value may be defined by the protocol, or may be preconfigured in the first core network.

In other words, in S730, the generation of the first PDU session identifier and the generation of the second PDU session identifier may not occur simultaneously.

Optionally, before S710, the method 700 further includes: S701, the second core network device sends a second request message, correspondingly, the first core network device receives the second request message, and the second request message is used to request to pass The first access technology creates a second session, and the second request message includes a second EBI of the second session.

That is, before creating the first session, the first core network device receives a second request message from the second core network device, the second request message is used to request to create a second session through the first access technology, and the second request message includes the first The second EBI of the second session.

S702. The first core network device generates a third PDU session identifier according to the second EBI and the first preset value.

The first core network device may generate a third PDU session identifier according to the second EBI and the first preset value, that is, the first core network device may convert the second EBI identifying the second session into a third PDU session identifier, and pass the third The PDU session identifier is used to identify the second session. Wherein, the first preset value depends on the PDU session generation rule defined in the protocol.

Optionally, the method 700 further includes: S740, the first core network device determines that the first PDU session identifier is a repeated identifier of the terminal device.

Wherein, the first core network device determining that the first PDU session identifier is a duplicate identifier of the terminal device includes: the first core network device determining that the third PDU session identifier is the same as the first PDU session identifier.

In S730, the first core network device generates the first PDU session identifier according to the first EBI and the first preset value, if the first core network device determines the first PDU session identifier and the previously generated third PDU session identifier by comparing If they are the same, it is determined that the first PDU session identifier is a repeated identifier of the terminal device.

Optionally, after S702, the first core network device receives a third request message, where the third request message is used to request the second session of the terminal device to switch from the first access technology to the second access technology. During the handover process, the first core network device will send a release message to the second core network device, where the release message is used to release the second EBI identifying the second session. After receiving the release message, the second core network device will release the second EBI, so that when the EBI is allocated for the first session, the allocated first EBI may be the same as the second EBI.

In an implementation manner, the first preset value is determined according to the first access technology, the second preset value is determined according to the first preset value, and the second preset value is different from the first preset value.

That is, the first core network device may use a second preset value different from the first preset value to generate the second PDU session identifier.

That is, the terminal device needs to initiate the first session through the 3GPP access technology.

In an implementation manner, the first access technology is a 3GPP access technology, and the second core network device is an MME.

When the terminal device needs to initiate the first session through the 3GPP access technology, the MME in the 3GPP access network will allocate the first EBI for the established first session, and the MME will send the first request message to the first core network device.

In an implementation manner, the first access technology is a 3GPP access technology, and the first preset value is 64.

That is to say, the first core network device generates the first PDU session identifier according to the first access technology, that is, the generation rule of the PDU session identifier in the 3GPP access technology. It is stipulated in the protocol TS 29.571 that for the access network using 3GPP technology, the SMF/PGW-C network element adds 64 to the default bearer identifier assigned by the MME, that is, the first preset value is 64.

That is, the terminal device needs to initiate the first session through the N3GPP access technology.

In an implementation manner, the first access technology is an N3GPP access technology, and the second core network device is an MME.

When the terminal device needs to initiate the first session through the N3GPP access technology, the ePDG in the N3GPP access network will allocate the first EBI for the established first session, and the ePDG will send the first request message to the first core network device.

In an implementation manner, the first access technology is an N3GPP access technology, and the first preset value is 80.

That is to say, the first core network device generates the first PDU session identifier according to the first access technology, that is, the generation rule of the PDU session identifier in the N3GPP access technology. It is stipulated in the protocol TS 29.571 that for the access network using N3GPP technology, the SMF/PGW-C network element adds 80 to the default bearer identifier assigned by ePDG, that is, the first default value is 80.

In an implementation manner, the first access technology is a 3GPP access technology, and the second preset value is any one of 96, 128, 160, 192, and 224.

In an implementation manner, the first access technology is an N3GPP access technology, and the second preset value is any one of 112, 144, 176, 208, and 240.

Since the value range of EBI is 0 to 15, it is defined in the agreement that in the 3GPP access technology, the first default value is 64, and in the N3GPP access technology, the first default value is 80, so that in the 3GPP access In the technology, the value of the PDU session identifier is 64-79, and in the N3GPP access technology, the value of the PDU session identifier is 80-95. Therefore, when determining that the first PDU session identifier is a repeated identifier of the terminal device, the first core network device may enable a new segment to generate the PDU session, specifically, use a second preset value different from the first preset value. set value. For example, in the 3GPP access technology, the second preset value may be any one of 96, 128, 160, 192, and 224. In the N3GPP access technology, the second preset value is any one of 112, 144, 176, 208, and 240.

Optionally, the value of the second preset value can also be in the following manner: in the N3GPP access technology, it is any one of 96, 128, 160, 192, and 224, and in the 3GPP access technology, it is 112, 144, 176 , 208, 240 any one.

Optionally, the second preset value may be any value from 96 to 255.

It should be understood that the above second preset value is only an example. In practical applications, as long as it can be distinguished from the first preset value and does not conflict with the value of the existing PDU session identifier, this application does not make any limited.

In an implementation manner, the method 700 further includes: S740, the third core network device stores the mapping relationship between the terminal device identifier and the second PDU session identifier.

The policy control network element and/or the charging function network element may save the mapping relationship between the identifier of the terminal device and the second PDU session identifier, so as to manage the first session of the terminal device through the second PDU session identifier.

The specific implementation of the communication method 700 provided by the present application will be described below with reference to FIG. 8 . FIG. 8 is another schematic flowchart of a communication method provided by an embodiment of the present application. It should be understood that, in the method 800 in FIG. 8 , the first access technology in the method 700 is the 3GPP access technology, and the second access technology is the N3GPP access technology as an example for description.

S801. When the terminal device initiates session #2 through the 3GPP access technology, the core network device initiates the session #2 creation process through the 3GPP technology. At this time, the MME sends a session #2 creation request to the SMF/PGW-C through the SGW (create session request) message #1, including EBI #2 for identifying session #2 in message #1. For example, the value of EBI#2 is 5.

Optionally, the message #1 may include an HI flag bit, for example, the value of this field is 0, indicating that the session #2 of the terminal device is an initially established session.

For example, session #2 is a voice service, and the form of the creation request message #1 of session #2 may be: Create Session Request (APN=voice, EBI=5).

S802. The SMF/PGW-C generates a PDU session ID #3 according to the EBI #2.

Since the session #2 is a session initiated through the 3GPP access technology, the SMF/PGW-C generates the PDU session identifier #3 based on the first preset value of 64 according to the protocol. For example, the generated token #3 is 5+64=69.

S803, the SMF/PGW-C sends a create request (create request) message #2 to the CHF, and the message #2 includes the identifier #3.

SMF/PGW-C can send creation request message #2 to CHF through N40 interface.

S804. The CHF saves the mapping relationship between the identifier of the terminal device and the identifier #3.

For example, the identifier of the terminal device is IMSI#1, and the CHF stores the mapping relationship #1 between IMSI#1 and identifier #3.

S805, the SMF/PGW-C sends a creation request message #3 to the PCF, and the message #3 includes the identifier #3.

SMF/PGW-C can send creation request message #3 to PCF through N7 interface.

It should be understood that the sending order of message #2 and message #3 is not limited, that is, the order of S803 and S804 is not limited.

S806. The PCF saves the mapping relationship between the identifier of the terminal device and the identifier #3.

For example, the identifier of the terminal device is IMSI#1, and the PCF stores the mapping relationship #2 between IMSI#1 and identifier #3.

S807. When the mobility handover of the terminal equipment occurs, the 3GPP technical access network is switched to the N3GPP technical access network, and the session #2 will be switched to the N3GPP technical access network. At this time, the ePDG will send the session to the SMF/PGW-C Creation request message #4 of #2, message #4 includes EBI #3 reallocated by the ePDG. Since EBI#3 and EBI#3 are allocated by different network elements, it may happen that the allocated EBI values are the same. For example, the value of EBI#3 is 5.

Message #4 may also include an HI flag bit, for example, if this field takes a value of 1, it indicates that session #2 of the terminal device is a handover session. Or it can also be understood as indicating that the session #2 of the terminal device is switched from the 3GPP access technology to the N3GPP access technology.

For example, the form of the creation request message #4 of session #2 may be: Create Session Request (EBI=5).

S808, the SMF/PGW-C generates a PDU session ID #4 according to the EBI #3.

Since the session #2 is switched to the N3GPP access technology, the SMF/PGW-C generates the PDU session identifier #4 according to the first preset value of 80 according to the agreement. For example, the generated token #4 is 5+80=85.

S809, the SMF/PGW-C sends an update request message #1 to the CHF.

The existing protocol does not specify how the session identifier in the N40 interface should be updated in the handover scenario. That is, although the identifier #4 is generated in S808, according to the existing protocol flow, the update request message #1 will not include the identifier #4, and the update request message #1 will not include the identifier #4. The identity included in message #1 is still identity #3.

For example, the format of the update request message #1 may be: Nchf_ConvergedCharging_Update Requestet (PduSessionId1=5+64=69, ChargingId1=ChargingIdA).

S810, the CHF saves the identifier #3 according to the update request message #1.

That is, although the session #2 of the terminal device is switched to the N3GPP access technology, and the SMF/PGW-C generates the identifier #4, after S807 to S810, on the CHF, the PDU session identifier used to identify the session #2 is still the identifier #3.

S811, the SMF/PGW-C sends an update request message #2 to the PCF.

In the existing protocol, the update request message sent to the PCF does not support carrying the PDU session identifier, that is, although the identifier #2 is generated in S808, according to the existing protocol flow, the update request message #2 will not include the identifier #2.

For example, the form of update request message #2 may be: Npcf_SMPolicyControl_Update Requestet().

S812. Since the update request message #2 does not include the PDU session identifier, the PCF will not change the locally stored identifier #3.

That is, although the session #2 of the terminal device is switched to the N3GPP access technology, and the SMF/PGW-C generates the identifier #4, after S807 to S812, on the PCF, the PDU session identifier used to identify the session #2 is still the identifier #3.

It should be understood that the sending order of the update request message #1 and the update request message #2 is not limited, that is, the sequence of S809 and S811 is not limited.

S813, the SMF/PGW-C sends a release message to the MME through the SGW, for example, a delete bearer request (delete bearer request) message, carrying the identifier of the session where the handover occurs, that is, EBI#2.

After receiving the release message, the MME will release the EBI#2 identifying the session #2.

S814, when the terminal device initiates the session #1 again through the 3GPP access technology, similar to S801 to S806, the core network device initiates the creation process of the session #1 through the 3GPP technology. At this time, the MME sends a creation request message #5 of the session #1 to the SMF/PGW-C through the SGW.

Similarly, the message #5 may include the EBI #1 allocated by the MME for the session #1. Since the EBI #2 generated by the MME for the session #2 has been released in S813, the EBI #1 allocated by the MME for the session #1 may It will be the same as the EBI#2 assigned to session #2 before, for example, the value of EBI#1 is 5.

For example, session #1 is a multimedia message service, and the form of creating request message #5 of session #1 may be: Create Session Request (APN=mms, EBI=5).

S815, SMF/PGW-C generates PDU session identifier #1 according to EBI #1.

S816, the SMF/PGW-C determines that the identity #1 is the same as the identity #3 generated in S802, that is, it is determined that the identity #1 is a repeated identity of the terminal device, and then the SMF/PGW-C generates session #1 according to the second preset value PDU session identifier #2.

For example, in the 3GPP access technology, the second preset value may be 96, so the identifier #2 is 5+96=101.

S817, the SMF/PGW-C sends a create request (create request) message #6 to the CHF, and the message #6 includes the identifier #2.

SMF/PGW-C can send creation request message #6 to CHF through N40 interface.

For example, the form of the create request message #6 may be: Nchf_ConvergedCharging_Create Requestet (PduSessionId2=5+96=101, ChargingId2=ChargingIdB).

S818. The CHF saves the mapping relationship between the identifier of the terminal device and the identifier #2.

For example, the identity of the terminal device is IMSI#1, and the CHF stores the mapping relationship #3 between IMSI#1 and identity #2.

S819, the SMF/PGW-C sends a creation request message #7 to the PCF, and the message #7 includes the identifier #2.

SMF/PGW-C can send creation request message #7 to PCF through N7 interface.

For example, the form of the create request message #7 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId2=5+96=101).

It should be understood that the sending order of message #6 and message #7 is not limited, that is, the order of S817 and S819 is not limited.

S820, the PCF saves the mapping relationship between the identifier of the terminal device and the identifier #2.

For example, the identifier of the terminal device is IMSI#1, and the PCF stores the mapping relationship #4 between IMSI#1 and identifier #2.

At this time, in CHF and PCF, the PDU session identifier identifying session #2 is still identifier #3, but the PDU session identifier identifying session #1 is generated as identifier #2 in S815 to S816, and there will be no repetition. That is to say, in the method of the present application, by carrying the second PDU session identifier different from the first PDU session identifier in the creation message, it is avoided that the network element with the policy control function and/or the network element with the charging function receives the connection with the first session. The PDU session identifier repeats the session identifier, so that multiple services of the terminal device can be performed at the same time, improving user experience.

It should be understood that the values of the HI flag bits in S801 and S807 are for illustration only, and are not limited in this application.

Another specific implementation of the communication method 700 provided by the present application will be described below with reference to FIG. 9 . FIG. 9 is another schematic flowchart of a communication method 900 provided by an embodiment of the present application. It should be understood that, in the method 900 in FIG. 9 , the first access technology in the method 700 is an N3GPP access technology, and the second access technology is a 3GPP access technology as an example for description.

S901. When the terminal device initiates session #2 through the N3GPP access technology, the core network device initiates the session #2 creation process through the N3GPP technology. At this time, the ePDG sends a session #2 creation request message to the SMF/PGW-C# 1. Message #1 includes EBI #2 for identifying session #2. For example, the value of EBI#2 is 6.

For example, session #2 is a voice service, and the form of the creation request message #1 of session #2 may be: Create Session Request (APN=voice, EBI=6).

S902, the SMF/PGW-C generates a PDU session ID #3 according to the EBI #2.

Since the session #2 is a session initiated through the 3GPP access technology, the SMF/PGW-C generates the PDU session identifier #3 according to the first preset value of 80 according to the protocol. For example, the generated token #3 is 6+80=86.

S903, the SMF/PGW-C sends a create request (create request) message #2 to the CHF, and the message #2 includes the identifier #3.

SMF/PGW-C can send creation request message #2 to CHF through N40 interface.

S904, the CHF saves the mapping relationship between the identifier of the terminal device and the identifier #3.

S905, the SMF/PGW-C sends a creation request message #3 to the PCF, and the message #3 includes the identifier #3.

SMF/PGW-C can send creation request message #3 to PCF through N7 interface.

It should be understood that the sending order of message #2 and message #3 is not limited, that is, the order of S903 and S904 is not limited.

S906. The PCF saves the mapping relationship between the identifier of the terminal device and the identifier #3.

S907. When the mobility handover of the terminal equipment occurs, the N3GPP technical access network is switched to the 3GPP technical access network, and the session #2 will be switched to the N3GPP technical access network. At this time, the MME will communicate with the SMF/PGW-C through the SGW Send the creation request message #4 of the session #2, and the message #4 includes the EBI #3 reallocated by the MME. Since EBI#3 and EBI#3 are allocated by different network elements, it may happen that the allocated EBI values are the same. For example, the value of EBI#3 is 6.

For example, the form of the creation request message #4 of session #2 may be: Create Session Request (EBI=6).

S908, the SMF/PGW-C generates a PDU session ID #4 according to the EBI #3.

Since the session #2 is switched to the 3GPP access technology, the SMF/PGW-C generates the PDU session identifier #4 according to the first preset value of 64 according to the agreement. For example, the generated token #4 is 6+64=70.

S909, the SMF/PGW-C sends an update request message #1 to the CHF.

The existing protocol does not specify how the session identifier in the N40 interface should be updated in the handover scenario. That is, although the identifier #4 is generated in S908, according to the existing protocol flow, the update request message #1 will not include the identifier #4. The identity included in message #1 is still identity #3.

S910, the CHF saves the identifier #3 according to the update request message #1.

That is, although the session #2 of the terminal device is switched to the 3GPP access technology, and the SMF/PGW-C generates the identifier #4, after S907 to S910, on the CHF, the PDU session identifier used to identify the session #2 is still the identifier #3.

S911, the SMF/PGW-C sends an update request message #2 to the PCF.

In the existing protocol, the update request message sent to the PCF does not support carrying the PDU session identifier, that is, although the identifier #2 is generated in S908, according to the existing protocol flow, the update request message #2 will not include the identifier #2.

S912. Since the update request message #2 does not include the PDU session identifier, the PCF will not change the locally stored identifier #3.

That is, although the session #2 of the terminal device is switched to the N3GPP access technology, and the SMF/PGW-C generates the identifier #4, after S907 to S912, on the PCF, the PDU session identifier used to identify the session #2 is still the identifier #3.

It should be understood that the sending order of the update request message #1 and the update request message #2 is not limited, that is, the sequence of S909 and S911 is not limited.

S913, the SMF/PGW-C sends a release message to the ePDG, for example, a delete bearer request (delete bearer request) message, carrying the identifier of the session where the handover occurs, that is, EBI#2.

S914, when the terminal device initiates the session #1 again through the N3GPP access technology, similar to S901 to S906, the core network device initiates the creation process of the session #1 through the N3GPP technology. At this point, the ePDG sends a session #1 creation request message #5 to the SMF/PGW-C.

Similarly, the message #5 may include the EBI #1 allocated by the ePDG for the session #1. Since the EBI #2 generated by the ePDG for the session #2 has been released in S913, the EBI #1 allocated by the ePDG for the session #1 may It will be the same as the EBI#2 assigned to session #2 before, for example, the value of EBI#1 is 6.

For example, session #1 is a multimedia message service, and the form of creating request message #5 of session #1 may be: Create Session Request (APN=mms, EBI=6).

S915, the SMF/PGW-C generates a PDU session identifier #1 according to the EBI #1.

Since the session #1 is a session initiated by the N3GPP access technology, the SMF/PGW-C generates the PDU session identifier #1 according to the first preset value of 80 according to the protocol. For example, the generated token #1 is 6+80=86.

S916, the SMF/PGW-C determines that the identity #1 is the same as the identity #3 generated in S902, that is, it is determined that the identity #1 is a repeated identity of the terminal device, and then the SMF/PGW-C generates session #1 according to the second preset value PDU session identifier #2.

For example, in the N3GPP access technology, the second preset value may be 112, so the identifier #2 is 6+112=118.

S917, the SMF/PGW-C sends a create request (create request) message #6 to the CHF, and the message #6 includes the identifier #2.

SMF/PGW-C can send creation request message #6 to CHF through N40 interface.

For example, the form of the create request message #6 may be: Nchf_ConvergedCharging_Create Requestet (PduSessionId2=6+112=118, ChargingId2=ChargingIdB).

S918. The CHF saves the mapping relationship between the identifier of the terminal device and the identifier #2.

S919, the SMF/PGW-C sends a creation request message #7 to the PCF, and the message #7 includes the identifier #2.

SMF/PGW-C can send creation request message #7 to PCF through N7 interface.

For example, the form of the create request message #7 may be: Npcf_SMPolicyControl_Create Requestet(PduSessionId2=6+112=118).

It should be understood that the sending order of message #6 and message #7 is not limited, that is, the order of S917 and S919 is not limited.

S920, the PCF saves the mapping relationship between the identifier of the terminal device and the identifier #2.

At this time, in CHF and PCF, the PDU session identifier identifying session #2 is still identifier #3, but the PDU session identifier identifying session #1 is generated as identifier #2 in S915 to S916, and there will be no repetition. That is to say, in the method of the present application, by carrying the second PDU session identifier different from the first PDU session identifier in the creation message, it is avoided that the network element with the policy control function and/or the network element with the charging function receives the connection with the first session. The PDU session identifier repeats the session identifier, so that multiple services of the terminal device can be performed at the same time, improving user experience.

It should be understood that the values of the HI flag bits in S901 and S907 are for illustration only, and are not limited in this application.

The communication method provided by the embodiment of the present application has been described in detail above with reference to FIG. 1 to FIG. 9 , and the communication device provided by the embodiment of the present application will be described below with reference to FIG. 10 to FIG. 11 . It should be understood that the devices shown in FIG. 10 to FIG. 11 can implement each step in the above method, and for the sake of brevity, details are not repeated here.

Fig. 10 is a schematic block diagram of a communication device provided by the present application. As shown in FIG. 10 , the communication device 1000 may include a transceiver unit 1010 and/or a processing unit 1020 .

The transceiving unit 1010 may include a sending unit and/or a receiving unit. The transceiving unit 1010 may be a transceiver (including a transmitter and/or receiver), an input/output interface (including an input and/or output interface), a pin or a circuit, and the like. The transceiver unit 1010 may be configured to perform the sending and/or receiving steps in the above method embodiments.

The processing unit 1020 may be a processor (may include more than one), a processing circuit with a processor function, etc., and may be used to execute other steps in the above method embodiments except sending and receiving.

Optionally, the communication device may further include a storage unit, which may be a memory, an internal storage unit (for example, a register, a cache, etc.), an external storage unit (for example, a read-only memory, a random access memory, etc.), etc. . The storage unit is used to store instructions, and the processing unit 1020 executes the instructions stored in the storage unit, so that the communication device executes the above method.

In one design, the communication device 1000 may correspond to the first core network device in the above method 400, method 500, and method 600, and may execute the method 400, method 500, and method 600 by the first core network device, SMF/ Operations performed by PGW-C.

For example, the transceiver unit 1010 is configured to receive a first request message, the first request message is used to request the first session of the terminal device to switch from the first access technology to the second access technology, and the first request message includes the first The first evolved packet system bearer identifier EBI of the session. The transceiver unit 1010 may also be configured to: send an update message to the third core network device, where the update message includes a first PDU session identifier, and the first PDU session identifier is generated according to the first EBI and a first preset value.

It should be understood that the transceiver unit 1010 and the processing unit 1020 may also perform other operations performed by the first core network device and the SMF/PGW-C in any of the

methods

400, 500, and 600 above, which will not be described here one by one. detail.

In one design, the communication device 1000 may correspond to the third core network device in the above method 400, method 500, and method 600, and may execute the method 400, method 500, and method 600 by the third core network device, PCF or Actions performed by CHF.

For example, the transceiver unit 1010 is configured to receive an update message from a first core network device, where the update message includes a first PDU session identifier, the first PDU session identifier is generated according to a first EBI, and the first EBI is used to identify a terminal The first session of the device. The processing unit 1020 is configured to save the mapping relationship between the terminal device identifier and the first PDU session identifier.

It should be understood that the transceiver unit 1010 and the processing unit 1020 may also perform other operations performed by the third core network device, the PCF or the CHF in the foregoing method 400, method 500, and method 600, which will not be described in detail here.

In one design, the communication device 1000 may correspond to the second core network device in the above method 400, method 500, and method 600, and may execute the method 400, method 500, and method 600 by the second core network device, MME or Operations performed by the ePDG.

For example, the transceiver unit 1010 is configured to send a first request message to the first core network device, where the first request message is used to request the first session of the terminal device to switch from the first access technology to the second access technology, the first The request message includes the first EPS bearer identifier EBI of the first session.

It should be understood that the transceiving unit 1010 and the processing unit 1020 may also perform other operations performed by the second core network device, MME or ePDG in the foregoing method 400, method 500, and method 600, which will not be described in detail here.

In one design, the communication device 1000 may correspond to the first core network device in the above method 700, method 800, and method 900, and may execute the method 700, method 800, and method 900 by the first core network device, SMF/ Operations performed by PGW-C.

For example, the transceiver unit 1010 is configured to receive a first request message, the first request message is used to request to create a first session of the terminal device through the first access technology, and the first request message includes the first evolution of the first session The packet system bearer identity EBI. The transceiver unit 1010 may also be configured to: when determining that the first PDU session identifier is a repeated identifier of the terminal device, send a creation message to the third core network device, where the creation message includes the second PDU session identifier, the second PDU session identifier and the second PDU session identifier. The PDU session identifiers are different, and the first PDU session identifier is generated according to the first EBI and the first preset value.

methods

700, 800, and 900 above, which will not be described here one by one. detail.

In one design, the communication device 1000 may correspond to the third core network device in the above method 700, method 800, and method 900, and may execute the method 700, method 800, and method 900 by the third core network device, PCF or Actions performed by CHF.

For example, the transceiver unit 1010 is configured to receive a creation message from the first core network device, the creation message includes a second PDU session identifier, the second PDU session identifier is different from the first PDU session identifier, and the first PDU session identifier is based on The first EBI and the first preset value are generated, where the first EBI is used to identify the first session of the terminal device. The processing unit 1020 is configured to save the mapping relationship between the identifier of the terminal device and the second PDU session.

It should be understood that the transceiver unit 1010 and the processing unit 1020 may also perform other operations performed by the third core network device, PCF or CHF in the foregoing method 700, method 800, and method 900, which will not be described in detail here.

In one design, the communication device 1000 may correspond to the second core network device in the above method 700, method 800, and method 900, and may execute the method 700, method 800, and method 900 by the second core network device, MME or Operations performed by the ePDG.

For example, the transceiver unit 1010 is configured to send a first request message to the first core network device, the first request message is used to request to create a first session of the terminal device through the first access technology, and the first request message includes the first The first evolved packet system bearer identifier EBI of the session.

It should be understood that the transceiving unit 1010 and the processing unit 1020 may also perform other operations performed by the second core network device, MME or ePDG in the foregoing method 700, method 800, and method 900, which will not be described in detail here.

It should be understood that, in the device 1000, the above-mentioned transceiver unit 1010 may include a receiving unit 1011 and a sending unit 1012, wherein the receiving unit 1011 is used to perform the receiving function in the above-mentioned transceiver unit 1010, and the sending unit 1012 is used to perform the receiving function in the above-mentioned transceiver unit 1010. send function.

Fig. 11 is a structural block diagram of a communication device provided according to an embodiment of the present application. The communication device 1100 shown in FIG. 11 includes: a processor 1110 , a memory 1120 and a transceiver 1130 . The processor 1110 is coupled with the memory 1120 for executing instructions stored in the memory 1120 to control the transceiver 1130 to send signals and/or receive signals.

It should be understood that the foregoing processor 1110 and memory 1120 may be combined into one processing device, and the processor 1110 is configured to execute program codes stored in the memory 1120 to implement the foregoing functions. During specific implementation, the memory 1120 may also be integrated in the processor 1110 , or be independent of the processor 1110 . It should be understood that the processor 1110 may also correspond to each processing unit in the foregoing communication device, and the transceiver 1130 may correspond to each receiving unit and sending unit in the foregoing communication device.

It should also be understood that the transceiver 1130 may include a receiver (or called a receiver) and a transmitter (or called a transmitter). The transceiver may further include antennas, and the number of antennas may be one or more. A transceiver may also be a communication interface or interface circuit.

Specifically, the communication device 1100 may correspond to the first core network device in the method 400, the method 500, and the method 600 according to the embodiment of the present application, the third core network device in the method 400, the method 500, and the method 600, and the method 400 , the second core network device in method 500, method 600, the first core network device in method 700, method 800, method 900, the third core network device in method 700, method 800, method 900, or, method 700 , the second core network device in the method 800, and the method 900. The communication apparatus 1100 may include the unit of the method performed by the first core network device in the method 400, the method 500, and the method 600, the unit of the method performed by the third core network device in the method 400, the method 500, and the method 600, and the method 400 , the unit of the method performed by the second core network device in the method 500 and the method 600, the unit of the method performed by the first core network device in the method 700, the method 800 and the method 900, and the unit in the method 700, the method 800 and the method 900 The unit of the method performed by the third core network device, or the unit of the method performed by the second core network device in method 700 , method 800 , or method 900 . It should be understood that the specific process for each unit to perform the above corresponding steps has been described in detail in the above method embodiments, and for the sake of brevity, details are not repeated here.

When the communication device 1100 is a chip, the chip includes a transceiver unit and a processing unit. Wherein, the transceiver unit may be an input-output circuit or a communication interface; the processing unit may be a processor or a microprocessor or an integrated circuit integrated on the chip.

In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the methods disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the field such as random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, register. The storage medium is located in the memory, and the processor reads the information in the memory, and completes the steps of the above method in combination with its hardware. To avoid repetition, no detailed description is given here.

It should be noted that the processor in the embodiment of the present application may be an integrated circuit chip, which has a signal processing capability. In the implementation process, each step of the above-mentioned method embodiments may be completed by an integrated logic circuit of hardware in a processor or instructions in the form of software. The above-mentioned processor may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components . Various methods, steps, and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module can be located in a mature storage medium in the field such as random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, register. The storage medium is located in the memory, and the processor reads the information in the memory, and completes the steps of the above method in combination with its hardware.

According to the method provided in the embodiment of the present application, the present application also provides a computer program product, the computer program product including: computer program code, when the computer program code is run on the computer, the computer is made to execute the computer program described in Fig. 4 to Fig. 9 . The method of any one of the embodiments is illustrated.

According to the methods provided in the embodiments of the present application, the present application also provides a computer-readable medium, the computer-readable medium stores program codes, and when the program codes are run on a computer, the computer is made to perform the operations shown in Fig. 4 to Fig. 9 . The method of any one of the embodiments is illustrated.

According to the method provided in the embodiments of the present application, the present application also provides a system, which includes the first core network device, the second core network device and/or the third core network device in any one of the embodiments shown in Fig. 4 to Fig. 6 The core network device, alternatively, includes the first core network device, the second core network device, and/or the third core network device in any one of the embodiments shown in FIG. 7 to FIG. 9 .

In the embodiments of the present application, words such as "exemplary" and "for example" are used as examples, illustrations or descriptions. Any embodiment or design described herein as "example" is not to be construed as preferred or advantageous over other embodiments or designs. Rather, the use of the word example is intended to present concepts in a concrete manner.

In the embodiments of the present application, "corresponding (corresponding, relevant)" and "corresponding (corresponding)" may sometimes be used interchangeably. It should be noted that when the difference is not emphasized, the meanings they intend to express are consistent.

The network architecture and business scenarios described in the embodiments of the present application are for more clearly illustrating the technical solutions of the embodiments of the present application, and do not constitute limitations on the technical solutions provided by the embodiments of the present application. For the evolution of architecture and the emergence of new business scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

Reference to "one embodiment" or "some embodiments" or the like in this specification means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in other embodiments," etc. in various places in this specification are not necessarily All refer to the same embodiment, but mean "one or more but not all embodiments" unless specifically stated otherwise. The terms "including", "comprising", "having" and variations thereof mean "including but not limited to", unless specifically stated otherwise.

In this application, "at least one" means one or more, and "multiple" means two or more. "And/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B, which may indicate: including the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A, B can be singular or plural.

It should be understood that, in various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the order of execution, and the execution order of the processes should be determined by their functions and internal logic, and should not be used in the embodiments of the present application. The implementation process constitutes any limitation.

It should be understood that in various embodiments of the present application, the first, second and various numbers are only for convenience of description and are not used to limit the scope of the embodiments of the present application. For example, distinguish bandwidth under different conditions, etc.

It should also be understood that the memory mentioned in the embodiments of the present application may be a volatile memory and/or a nonvolatile memory. Among them, the non-volatile memory can be read-only memory (read-only memory, ROM), programmable read-only memory (programmable ROM, PROM), erasable programmable read-only memory (erasable PROM, EPROM), electrically programmable Erases programmable read-only memory (electrically EPROM, EEPROM) or flash memory. The volatile memory may be random access memory (RAM). For example, RAM can be used as an external cache. As an example and not limitation, RAM may include the following forms: static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM) , double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (synchlink DRAM, SLDRAM) and Direct memory bus random access memory (direct rambus RAM, DR RAM).

It should also be noted that the memories described herein are intended to include, but are not limited to, these and any other suitable types of memories.

Those skilled in the art can appreciate that the units and steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Professionals may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the protection scope of the present application.

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

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to implement the solutions provided in this application.

In addition, each functional unit in each embodiment of the present application may be integrated into one unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

In the above embodiments, all or part of them may be implemented by software, hardware, firmware or any combination thereof. When implemented using software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the processes or functions according to the embodiments of the present application will be generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable devices. For example, the computer may be a personal computer, a server, or a network device. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website, computer, server or data center Transmission to another website site, computer, server, or data center by wired (eg, coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (eg, infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or a data center integrated with one or more available media. The available medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, DVD), or a semiconductor medium (for example, a solid state disk (solid state disk, SSD) etc. For example, the aforementioned available medium may include But not limited to: U disk, mobile hard disk, read-only memory (read-only memory, ROM), random access memory (random access memory, RAM), magnetic disk or optical disk and other media that can store program codes.

The above is only a specific implementation of the application, but the scope of protection of the application is not limited thereto. Anyone familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the application. Should be covered within the protection scope of this application. Therefore, the protection scope of the present application should be determined by the protection scope of the claims.

Claims

A communication method, characterized in that the method is executed by a first core network device, including:

Receive a first request message from a second core network device, where the first request message is used to request that the first session of the terminal device be switched from the first access technology to the second access technology, where the first request message includes The first evolved packet system bearer identifier EBI of the first session;

Send an update message to a policy control function network element and/or a charging function network element, where the update message includes a first PDU session identifier, where the first PDU session identifier is generated according to the first EBI and a first preset value.
The method according to claim 1, further comprising:

Generate the first PDU session identifier according to the first EBI and the first preset value.
The method according to claim 1 or 2, wherein the first access technology is a 3rd Generation Partnership Project 3GPP access technology, and the second access technology is a non-Third Generation Partnership Project N3GPP access technology.
The method according to claim 3, wherein the second core network device is an evolved packet data gateway (ePDG).
The method according to claim 3 or 4, wherein the first preset value is 80.
The method according to claim 1 or 2, wherein the first access technology is N3GPP access technology, and the second access technology is 3GPP access technology.
The method according to claim 6, wherein the second core network device is a Mobility Management Entity (MME).
The method according to claim 6 or 7, wherein the first preset value is 64.
A communication method, characterized in that the method is executed by a network element with a policy control function, including:

Receive an update message from the first core network device, where the update message includes a first PDU session identifier, the first PDU session identifier is generated according to the first EBI, and the first EBI is used to identify the first session of the terminal device ;

The mapping relationship between the identifier of the terminal device and the first PDU session identifier is stored.
A communication method, characterized in that the method is executed by a charging function network element, including:

Receive an update message from the first core network device, where the update message includes a first PDU session identifier, the first PDU session identifier is generated according to the first EBI, and the first EBI is used to identify the first session of the terminal device ;

The mapping relationship between the identifier of the terminal device and the first PDU session identifier is stored.
A communication method, characterized in that the method is executed by a first core network device, including:

receiving a first request message from a second core network device, where the first request message is used to request to create a first session of a terminal device through a first access technology, where the first request message includes the first session The first evolved packet system bearer identifier EBI;

When it is determined that the first PDU session identifier is the repeated identifier of the terminal device, a creation message is sent to the policy control function network element and/or the charging function network element, the creation message includes the second PDU session identifier, and the second The PDU session identifier is different from the first PDU session identifier, and the first PDU session identifier is generated according to the first EBI and a first preset value.
The method according to claim 11, characterized in that the method further comprises:

generating the first PDU session identifier according to the first EBI and the first preset value;

generating the second PDU session identifier according to the first EBI and a second preset value, where the second preset value is different from the first preset value.
The method according to claim 11 or 12, wherein, before receiving the first request message, the method further comprises:

receiving a second request message for requesting creation of a second session via the first access technology, the second request message including a second EBI of the second session;

generating a third PDU session identifier according to the second EBI and the first preset value;

The determining that the first PDU session identifier is the repeated identifier of the terminal device includes:

Determine that the third PDU session identifier is the same as the first PDU session identifier.
The method according to any one of claims 11 to 13, wherein the first access technology is a 3GPP access technology.
The method according to claim 14, wherein the second core network device is a Mobility Management Entity (MME).
The method according to claim 14 or 15, wherein the first preset value is 64.
The method according to any one of claims 11 to 13, wherein the first access technology is an N3GPP access technology.
The method according to claim 17, wherein the second core network device is an evolved packet data gateway (ePDG).
The method according to claim 17 or 18, wherein the first preset value is 80.
A communication device, characterized in that it comprises: a unit for performing each step in any one of claims 1 to 8, or the method according to claim 9 or 10, or as claimed in claims 11 to 19 A unit of each step in any one of the methods.
A communication device, characterized by comprising:

memory for storing computer instructions;

A processor configured to execute computer instructions stored in the memory so that the device performs the method according to any one of claims 1 to 8, or the method according to claim 9 or 10, or the method according to claim 1 The method described in any one of claims 11 to 19.
A computer-readable storage medium, characterized in that a computer program is stored thereon, and the computer program is used to perform the method according to any one of claims 1 to 8, or as described in claim 9 or 10 , or a method as claimed in any one of claims 11 to 19.
A system on a chip, characterized in that it includes: a processor, the processor is used to execute a stored computer program, and the computer program is used to execute the method according to any one of claims 1 to 8, or the A method as claimed in claim 9 or 10, or a method as claimed in any one of claims 11 to 19.
A computer program product comprising instructions, which, when run on a computer, causes the computer to perform the method according to any one of claims 1 to 8, or the method according to claim 9 or 10 , or a method as claimed in any one of claims 11 to 19.