CN118055394A

CN118055394A - Information transmission method, apparatus, communication device and readable storage medium

Info

Publication number: CN118055394A
Application number: CN202211437801.5A
Authority: CN
Inventors: 程思涵; 吕华章; 张奕忠; 王文
Original assignee: Vivo Mobile Communication Co Ltd
Current assignee: Vivo Mobile Communication Co Ltd
Priority date: 2022-11-15
Filing date: 2022-11-15
Publication date: 2024-05-17
Also published as: WO2024104077A1

Abstract

The application discloses an information transmission method, a device, a communication device and a readable storage medium, wherein the method comprises the following steps: the method comprises the steps that a first core network element generates first information, wherein the first information comprises at least one first PSI and strategy segmentation content corresponding to the at least one first PSI; the first core network element sends first policy information to a terminal, wherein the first policy information comprises the first information, and the first policy information is used for updating policy information stored by the terminal.

Description

Information transmission method, apparatus, communication device and readable storage medium

Technical Field

The application belongs to the technical field of communication, and particularly relates to an information transmission method, an information transmission device, communication equipment and a readable storage medium.

Background

The policy control function (Policy Control Function, PCF) is a core network device of the fifth generation mobile communication technology (5th Generation,5G), and the PCF may manage policy (policy) information stored in a terminal (e.g., user Equipment (UE)), for example, add, delete, modify, etc. operations are performed on policy information stored in the UE through a terminal policy management (UE policy management) procedure. When the PCF sends policy information to the UE, the PCF sends the policy information in the form of policy segments (policies) each corresponding to an identifier, i.e., a policy segment identifier (Policy Section Identifier, PSI).

How to update the policy information stored locally by the UE is a problem to be solved.

Disclosure of Invention

The embodiment of the application provides an information transmission method, an information transmission device, communication equipment and a readable storage medium, which solve the problem of updating policy information stored locally in UE.

In a first aspect, there is provided an information transmission method, including:

the method comprises the steps that a first core network element generates first information, wherein the first information comprises at least one first strategy segmentation identifier PSI and strategy segmentation content corresponding to the at least one first PSI;

The first core network element sends first policy information to a terminal, wherein the first policy information comprises the first information, and the first policy information is used for updating policy information stored by the terminal.

In a second aspect, there is provided an information transmission method, including:

The method comprises the steps that a terminal receives first strategy information sent by a first core network element, wherein the first strategy information comprises first information, the first information comprises at least one first PSI and strategy segmentation content corresponding to the at least one first PSI, and the first information is generated by the first core network element;

And the terminal updates the stored strategy information according to the first strategy information.

In a third aspect, there is provided an information transmission apparatus comprising:

The first generation module is used for generating first information, wherein the first information comprises at least one first policy segment identifier PSI and policy segment content corresponding to the at least one first PSI;

The first sending module is used for sending first strategy information to the terminal, the first strategy information comprises the first information, and the first strategy information is used for updating the strategy information stored by the terminal.

In a fourth aspect, there is provided an information transmission apparatus including:

A first receiving module, configured to receive first policy information sent by a first core network element, where the first policy information includes first information, where the first information includes at least one first PSI and policy segmentation content corresponding to the at least one first PSI, and the first information is generated by the first core network element;

and the updating module is used for updating the stored strategy information according to the first strategy information.

In a fifth aspect, there is provided a communication device comprising: a processor, a memory and a program or instruction stored on the memory and executable on the processor, which when executed by the processor, implements the steps of the method according to the first or second aspect.

In a sixth aspect, there is provided a readable storage medium having stored thereon a program or instructions which when executed by a processor implement the steps of the method according to the first or second aspect.

In a seventh aspect, there is provided a chip comprising a processor and a communication interface coupled to the processor for running a program or instructions implementing the steps of the method according to the first or second aspect.

In an eighth aspect, there is provided a computer program/program product stored in a non-transitory storage medium, the program/program product being executed by at least one processor to implement the steps of the method as described in the first or second aspect.

A ninth aspect provides a communication system comprising a terminal for performing the steps of the method according to the first or second aspect and a network side device for performing the steps of the method according to the first or second aspect.

In the embodiment of the application, the terminal can update the locally stored policy information by utilizing the received first policy information, for example, the terminal can update the locally stored policy information in a switching scene between base stations or other scenes.

Drawings

Fig. 1 is a schematic diagram of a registration flow of a terminal;

Fig. 2 is a schematic diagram of a wireless communication system according to an embodiment of the present application;

FIG. 3 is a flowchart of an information transmission method according to an embodiment of the present application;

FIG. 4 is a second flowchart of an information transmission method according to an embodiment of the present application;

FIG. 5 is a third flowchart of an information transmission method according to an embodiment of the present application;

FIG. 6 is a flowchart of a method for transmitting information according to an embodiment of the present application;

FIG. 7 is a fifth flowchart of an information transmission method according to an embodiment of the present application;

Fig. 8 is a schematic diagram of an information transmission device according to an embodiment of the present application;

FIG. 9 is a second schematic diagram of an information transmission device according to an embodiment of the present application;

Fig. 10 is a schematic diagram of a terminal according to an embodiment of the present application;

fig. 11 is a schematic diagram of a network side device according to an embodiment of the present application;

Fig. 12 is a schematic diagram of a communication device according to an embodiment of the present application.

Detailed Description

The technical solutions of the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which are derived by a person skilled in the art based on the embodiments of the application, fall within the scope of protection of the application.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application are capable of operation in sequences other than those illustrated or otherwise described herein, and that the "first" and "second" distinguishing between objects generally are not limited in number to the extent that the first object may, for example, be one or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/" generally means a relationship in which the associated object is an "or" before and after. The term "indicated" in the description and claims of the present application may be either an explicit indication or an implicit indication. The explicit indication may be understood as that the sender explicitly informs the receiver of the operation or request result that needs to be performed in the sent indication; the implicit indication is understood as that the receiving side judges according to the indication sent by the sending side, and determines the operation or the request result to be executed according to the judging result.

It should be noted that the techniques described in the embodiments of the present application are not limited to long term evolution (Long Term Evolution, LTE)/LTE evolution (LTE-Advanced, LTE-a) systems, but may also be used in other wireless communication systems, such as code division multiple access (Code Division Multiple Access, CDMA), time division multiple access (Time Division Multiple Access, TDMA), frequency division multiple access (Frequency Division Multiple Access, FDMA), orthogonal frequency division multiple access (OrthogonalFrequency Division Multiple Access, OFDMA), single carrier frequency division multiple access (Single-carrier FrequencyDivision Multiple Access, SC-FDMA), and other systems. The terms "system" and "network" in embodiments of the application are often used interchangeably, and the techniques described may be used for both the above-mentioned systems and radio technologies, as well as other systems and radio technologies. The following description describes a New Radio (NR) system for exemplary purposes and NR terminology is used in much of the following description, but these techniques may also be applied to applications other than NR system applications, such as 6 th Generation (6G) communication systems.

In order to facilitate understanding of the embodiments of the present application, the following technical points will be described first.

1. Regarding policy control functions (Policy Control Function, PCF).

The PCF is a fifth-generation mobile communication technology (5th Generation,5G) core network device, and the PCF may manage policy (policy) information stored in a terminal (e.g., user Equipment (UE)), for example, by performing operations such as adding (add), deleting (delete), modifying (modify) on policy information stored in the UE through a terminal policy management (UE policy management) procedure. When the PCF sends policy information to the UE, the PCF sends the policy information in the form of policy fragments (policysection), each policy section corresponds to an identifier (i.e., policy fragment identifier (PolicySection Identifier, PSI).

The policy section may contain several types of information: access network service discovery and Selection policies (Access NetworkDiscovery & Selection Policy, ANDSP), user routing policies (UE Route Selection Policy, URSP), vehicle-to-EVERYTHING POLICY, V2 XP), short range communication policies (Proximity-based Services Policy, proSeP).

2. Regarding URSP rule (rule).

URSP rule is a strategy defined by the third generation partnership project (3rd Generation Partnership Project,3GPP) for transmitting to a UE that can match an Application (APP) to a particular PDU session according to URPS rule. For example, when an application on the UE starts, the UE may use a priority according to each URSP rule to match from high to low. When a match is made to a URSP rule, a PDU session is created for the UE using the parameters of the PDU session (Protocol Data Unit) contained in the URSP rule, and the APP is transmitted using the existing PDU session matched to the parameters.

To facilitate transmission, the PCF places one or more policy information, e.g., URSP rule, in the policy section, which needs to be sent to the UE, and communicates the policy information to the UE in the form of the policy section. Each policy section has an identifier: PSI (Policy Section Identifier). The PCF sends all policy information, e.g., URSP rule, to the UE via one or more policy sections to be sent to the UE. At the time of transmission, each policy section contains 1 PSI and policy segment content corresponding to the PSI (policy section content).

The UE may carry its stored PSI list (list) for policy information synchronization with the network when sending a registration message to the network. The UE registration flow is as shown in fig. 1:

Step 101: the UE initiates a registration request, which includes a terminal policy container (UE Policy Container), and UE Policy Container includes the following:

(1) PSI list stored by UE;

(2) Information indicating whether the UE supports ANDSP;

(3) Operating system identification (operating SYSTEM IDENTIFIER, OSId) of the UE.

Step 102: the access and mobility management function (ACCESS AND Mobility Management Function, AMF) sends UE Policy Container to the PCF via a terminal policy control creation (Npcf _ UEPolicyControl Create) message.

Step 103: the PCF saves the PSI information to the unified data repository (Unified Data Repository, UDR) via a data management Create (Nudr _dm_create) message, while saving OSId and information on whether ANDSP is supported to the UDR.

Step 4: the UDR replies to the response message.

Step 5: the PCF replies with a response message.

Step 6: the AMF replies to the registration accept message.

Fig. 2 shows a block diagram of a wireless communication system to which embodiments of the present application are applicable. The wireless communication system includes a terminal 21 and a network device 22.

The terminal 21 may be a Mobile phone, a tablet computer (Tablet Personal Computer), a laptop (LaptopComputer), or a terminal-side device called a notebook, a Personal digital assistant (Personal DIGITAL ASSISTANT, PDA), a palm computer, a netbook, an ultra-Mobile Personal computer (ultra-Mobile Personal computer, UMPC), a Mobile internet appliance (Mobile INTERNET DEVICE, MID), an augmented reality (augmented reality, AR)/a virtual reality (virtualreality, VR) device, a robot, a wearable device (Wearable Device), a Vehicle-mounted device (Vehicle UserEquipment, VUE), a pedestrian terminal (PEDESTRIAN USER EQUIPMENT, PUE), an intelligent home (home device with a wireless communication function such as a refrigerator, a television, a washing machine, furniture, etc.), a game machine, a Personal Computer (PC), a teller machine, or a self-service machine, etc., the wearable device includes: intelligent wrist-watch, intelligent bracelet, intelligent earphone, intelligent glasses, intelligent ornament (intelligent bracelet, intelligent ring, intelligent necklace, intelligent anklet, intelligent foot chain etc.), intelligent wrist strap, intelligent clothing etc.. In addition to the above terminal device, the terminal according to the present application may be a Chip in the terminal, such as a Modem (Modem) Chip, a System on Chip (SoC). It should be noted that the specific type of the terminal 21 is not limited in the embodiment of the present application.

The network-side device 22 may include an access network device or a core network device, where the access network device may also be referred to as a radio access network device, a radio access network (Radio Access Network, RAN), a radio access network function, or a radio access network element. The access network devices may include base stations, wireless local area network (Wireless Local Area Networks, WLAN) access points, or wireless fidelity (WIRELESS FIDELITY, WIFI) nodes, etc., which may be referred to as node bs, evolved node bs

An access Point (eNB), a base transceiver station (Base Transceiver Station, BTS), a radio base station, a radio transceiver, a Basic service set (Basic SERVICE SET, BSS), an Extended service set (Extended SERVICESET, ESS), a home Node B, a home evolved Node B, a transmission and reception Point (TRANSMITTING RECEIVING Point, TRP), or some other suitable terminology in the field, so long as the same technical effect is achieved, the base station is not limited to a specific technical vocabulary, and it should be noted that in the embodiment of the present application, a base station in an NR system is only described as an example, and the specific type of the base station is not limited.

The core network device may include, but is not limited to, at least one of: core Network nodes, core Network functions, mobility management entities (Mobility MANAGEMENT ENTITY, MME), access and Mobility management functions (ACCESS AND MobilityManagement Function, AMF), session management functions (Session Management Function, SMF), user plane functions (User Plane Function, UPF), policy control functions (Policy Control Function, PCF), policy and Charging Rules Function (PCRF), edge application service discovery functions (Edge Application Server Discovery Function, EASDF), unified data management (Unified DATAMANAGEMENT, UDM), unified data warehousing (Unified Data Repository, UDR), home subscriber server (Home Subscriber Server, HSS), centralized Network configuration (Centralized Network configuration, CNC), network storage functions (Network Repository Function, NRF), network opening functions (Network ExposureFunction, NEF), local NEF (or L-NEF), binding support functions (Binding Support Function, BSF), application functions (Application Function, AF), and the like. It should be noted that, in the embodiment of the present application, only the core network device in the NR system is described as an example, and the specific type of the core network device is not limited.

Referring to fig. 3, an embodiment of the present application provides an information transmission method, which is applied to a first core network device, where the first core external network device includes, but is not limited to: the PCF comprises the following specific steps: step 301 and step 302.

Step 301: generating first information by a first core network element, wherein the first information comprises at least one first PSI and strategy segmentation content (policy section content) corresponding to the at least one first PSI;

The first information may also be referred to as a first PSI list, which includes at least one first PSI and policy segment contents corresponding to the at least one first PSI, and the policy segment contents herein may also be referred to as terminal policy segment contents (UE policy section content).

For example, the first information may include: PSI-1, policy segment content corresponding to PSI-1, PSI-2, policy segment content corresponding to PSI-2, PSI-3, policy segment content corresponding to PSI-3, as shown in Table 1.

Table 1: content in the first information.

PSI-1
	Policy section content corresponding to PSI-1
PSI-2
	Policy section content corresponding to PSI-2
PSI-3
	Policy section content corresponding to PSI-3

It should be noted that the PSI may be composed of 2 parts: public land mobile network (Public Land Mobile Network, PLMN) Identity (ID), policy segment code (Policy Section Code, PSC). Wherein the PLMNID consists of a mobile network code (Mobile Network Code, MNC) and a mobile country code (Mobile Country Code, MCC).

Alternatively, the PSI may also be referred to as a terminal policy segment identification (UE Policy Section Identifier, UPSI).

For example, in the following scenario, the first core network element may generate the first information.

Scenario 1, the ue replaces a subscriber identity card (Subscriber Identity Module, SIM) card, or a newly purchased terminal device, such as a cell phone. Under these scenarios, the PSI list and policy section content corresponding to each PSI are not stored in the UE, and the UE does not carry the PSI list in the register process. At this time, the PCF considers that policy information is not stored in the UE according to that the UE does not carry the PSI list, and the PCF further considers that policy information corresponding to the UE stored in the UDR is invalid information. The PCF does not acquire information from the UDR but generates new policy information itself and sends the newly generated policy information to the UE. The policy information includes at least one PSI, and policy section content corresponding to each PSI.

Scene 2: when the UE moves in the connected state, inter-base station handover (handover) may occur, and after the handover is completed, the UE may perform a mobility register procedure once, and may not carry PSI list in the mobility register procedure.

It is to be understood that the scenario in which the first core network element generates the first information is not limited to the two scenarios described above.

Step 302: the method comprises the steps that a first core network element sends first strategy information to a terminal, wherein the first strategy information comprises the first information, and the first strategy information is used for updating strategy information stored by the terminal.

The first policy information may also be referred to as a first terminal policy container, the policy information may also be referred to as a terminal policy container (UE Policy Container), and the policy information may include at least one PSI and policysection content corresponding to each PSI.

In one embodiment of the application, the method further comprises:

the first core network element acquires second information from a second core network element, wherein the second information comprises at least one second PSI of the terminal and strategy segmentation content corresponding to the at least one second PSI, which are stored by the second core network element;

The second information may also be referred to as a second PSI list, where the second PSI list includes at least one second PSI and policy-segmented content corresponding to the second PSI. For example, the second information may include PSI-1, policy segment content corresponding to the PSI-1, PSI-2, policy segment content corresponding to the PSI-2, as shown in Table 2.

Table 2: content in the second information.

PSI-1
	Policy section content corresponding to PSI-1
PSI-2
	Policy section content corresponding to PSI-2

The first core network element obtains third information according to the first information and the second information;

The first policy information further includes the third information, where the third information includes at least one third PSI and policy segment content corresponding to the at least one third PSI, and the policy segment content is empty (empty), or the third information includes at least one third PSI, and the third information does not include policy segment content corresponding to the at least one third PSI; the at least one third PSI is included in the second information and not included in the first information.

Optionally, the third information includes at least one third PSI, and the third information does not include policy section content corresponding to the at least one third PSI, which may be understood that the third information includes only the at least one third PSI.

The third information may also be referred to as a third PSI list, where the third PSI list includes at least one third PSI and policy-segmented content corresponding to the third PSI, and the policy-segmented content is set to be empty, or the third PSI list includes only at least one third PSI. For example, the third information contains the contents shown in table 3.

Table 3: content in the third information.

PSI-3

Or the third information contains the contents as shown in table 4.

Table 4: content in the third information.

PSI-3

The second core network element includes, but is not limited to, UDR.

In one embodiment of the application, the method further comprises:

the first core network element acquires information for indicating whether the terminal supports ANDSP from the second core network element;

In case of the terminal support ANDSP, the first core network element generates ANDSP;

And the first core network element sends ANDSP to the terminal.

In one embodiment of the present application, the first policy information further includes: fourth information indicating at least one of:

(1) The terminal stores the first information;

that is, the fourth information is used to instruct the terminal to save only the received first information.

(2) And deleting other PSIs except at least one first PSI contained in the first information and policy segmentation contents corresponding to the other PSIs by the terminal.

That is, the fourth information is used to instruct the terminal to delete other PSI that are locally stored and are not included in the first information, and policy segment contents corresponding to the PSI.

The terminal deleting other PSIs except at least one first PSI and policy segment contents corresponding to the other PSIs contained in the first information can also be understood as deleting policy segments corresponding to other PSIs except at least one first PSI contained in the first information.

In one embodiment of the application, the method further comprises:

the first core network element acquires a fourth PSI, wherein the fourth PSI is other PSIs except at least one first PSI contained in the first information;

the first policy information further includes a fourth PSI and policy segment content corresponding to the fourth PSI, where the policy segment content is empty; or the first policy information further includes the fourth PSI, and the first policy information does not include the policy segmentation content corresponding to the fourth PSI.

Optionally, the first policy information further includes the fourth PSI, and the first policy information does not include the policy section content corresponding to the fourth PSI, which may be understood that the first policy information includes only the first information and the fourth PSI, and the first policy information does not include the policy section content corresponding to the fourth PSI.

For example, the first information contains the contents as shown in table 5.

Table 5: content in the first information.

The first policy information includes, in addition to the first information: PSI-4, PSI-5, PSI-6, PSI-7, PSI-8, and policy section content for each of PSI-4, PSI-5, PSI-6, PSI-7, PSI-8, and policy section content for each of PSI-4, PSI-5, PSI-6, PSI-7, PSI-8 are all empty, see Table 6.

Table 6: the first policy information includes content in addition to the first information.

PSI-4

PSI-5

PSI-6

PSI-7

PSI-8

Or the first policy information includes only the first information in addition to the first information: PSI-4, PSI-5, PSI-6, PSI-7, PSI-8, see Table 7.

Table 7: the first policy information includes content in addition to the first information.

PSI-4
	PSI-5
PSI-6
	PSI-7
PSI-8

In one embodiment of the present application, the first core network element generates first information, including:

The first core network element generates first information in case the first core network element receives a request message not containing PSI (or PSI list).

Optionally, when the first core network element determines that the UE performs inter-base station handover and changes in PCF, the first core network element generates the first information when receiving a request message that does not include PSI (or PSI list).

For example, if the UE moves from the service area of AMF-1 to the service area of AMF-2 at the time of UE handover, the UE may be changed from PCF-1 to PCF-2 at the same time. At this time, the PCF-2 will also generate new policy information by itself and send the new policy information to the UE according to the UE not carrying PSI list, but not requesting the information of the UE from the UDR. At this time, there is a problem in that the UE saves redundant PSI information. For example, PCF-1 allocates 3 PSIs to the UE, PSI-1, PSI-2 and PSI-3, respectively. When the UE is switched, the PCF-2 provides service for the UE, and the PCF-2 distributes 2 PSIs for the UE, namely PSI-1 and PSI-2 respectively and sends the PSIs to the UE. At this time, the UE uses the contents of PSI-1 and PSI-2 sent by the network to replace policy section content corresponding to the saved PSI-1 and PSI-2, and deletes policy section content corresponding to PSI-3, so as to avoid that the UE establishes PDU session according to the contents of PSI-3, and can be refused by the network, thereby affecting the user experience.

In the embodiment of the application, the terminal can update the locally stored strategy information by utilizing the received first strategy information, for example, the terminal can update the locally stored strategy information in a switching scene among base stations or other scenes, and in the updating process, the terminal can delete the stored redundant PSI according to the received first strategy information, so that the problem that the terminal is refused by a network when establishing a PDU session by using the strategy segmentation content corresponding to the redundant PSI is avoided, and the user experience is improved.

Referring to fig. 4, an embodiment of the present application provides an information transmission method, applied to a terminal, including: step 401 and step 402.

Step 401: the method comprises the steps that a terminal receives first strategy information sent by a first core network element, wherein the first strategy information comprises first information, and the first information comprises at least one first PSI and strategy segmentation content corresponding to the at least one first PSI;

Step 402: and the terminal updates the stored strategy information according to the first strategy information.

In one embodiment of the present application, the first policy information further includes third information, the third information includes at least one third PSI and policy-segmented content corresponding to the at least one third PSI, the policy-segmented content corresponding to the at least one third PSI is null, or the third information includes at least one third PSI, the third information does not include the policy-segmented content corresponding to the at least one third PSI;

the terminal updates the stored strategy information according to the first strategy information, and the method comprises the following steps:

And under the condition that the terminal stores a fifth PSI which is the same as the at least one third PSI, the terminal locally deletes the fifth PSI and the strategy segmentation content corresponding to the fifth PSI.

Optionally, the third information includes at least one third PSI, and the third information does not include the corresponding policy segmentation content, which may be understood that the third information includes only at least one third PSI.

Optionally, the terminal locally deletes the fifth PSI and the policy segment content corresponding to the fifth PSI, which may also be understood that the terminal deletes the policy segment corresponding to the fifth PSI.

In one embodiment of the application, the method further comprises:

in case the terminal supports the access network service discovery and selection policy ANDSP, the terminal receives ANDSP sent by the first core network element.

In one embodiment of the present application, the first policy information further includes: fourth information indicating at least one of: the terminal stores the first information; the terminal deletes other PSIs except at least one first PSI contained in the first information and policy segmentation contents corresponding to the other PSIs;

and deleting other PSIs except at least one first PSI and policy segmentation contents corresponding to the other PSIs which are stored locally by the terminal.

Optionally, the terminal deletes other PSI's except the at least one first PSI stored locally and policy segment contents corresponding to other PSI's, which may also be understood that the terminal deletes policy segments corresponding to other PSI's except the at least one first PSI stored locally.

In one embodiment of the present application, the first policy information further includes a fourth PSI and policy section contents corresponding to the fourth PSI, the policy section contents being null, or the first policy information further includes a fourth PSI, the first policy information does not include the policy section contents corresponding to the fourth PSI, wherein the fourth PSI is other PSI than at least one first PSI included in the first information;

and under the condition that the terminal stores a sixth PSI which is the same as the fourth PSI, the terminal locally deletes the sixth PSI and the strategy segmentation content corresponding to the sixth PSI.

Optionally, the terminal locally deletes the sixth PSI and the content of the policy segment corresponding to the sixth PSI, which may also be understood that the terminal locally deletes the policy segment corresponding to the sixth PSI.

Optionally, the first policy information further includes a fourth PSI, where the first policy information does not include policy section content corresponding to the fourth PSI, and it may also be understood that the first policy information includes only the first information and the fourth PSI, and the first policy information does not include policy section content corresponding to the fourth PSI.

Embodiments of the present application will be described below with reference to example one, example two and example three.

Embodiment one:

the UE is handed over from the base station 1 to the base station 2 in the connected state, and changes from other AMFs to the AMFs in fig. 5 during the handover. Referring to fig. 5, the specific steps are as follows:

Step 501: after the handover is completed, the UE initiates a registration (register) request in which the terminal policy container (UE Policy Container) is not included, i.e., the registration request does not include a PSI list (list).

Step 502: the AMF sends a terminal policy control creation request (e.g., AMF Npcf _ UEPolicyControlCreate) message to the PCF for creating a terminal policy association (UE Policy Association).

Step 503: in the case that the PCF receives a terminal policy control creation request that does not include UE Policy Container, the PCF generates first information including at least one first PSI and policy segmentation content (policy section content) corresponding to the at least one first PSI, and the PCF sends a data management Query request (e.g., nudr _dm_query request) message to the UDR requesting to obtain the PSI corresponding to the UE, and the policy segmentation content corresponding to the PSI.

The policy segmentation content may also be referred to herein as terminal policy segmentation content (UE policy section content).

Alternatively, the PCF receives the terminal policy control creation request that does not include UE Policy Container, which may also be understood as the PCF receiving the terminal policy control creation request that does not include PSI list.

Step 504: the PCF receives a data Query response message (e.g., nudr _dm_query response) from the UDR, where the data Query response message carries second information, where the second information includes at least one second PSI of the terminal and policy segmentation content corresponding to the at least one second PSI, where the second PSI is stored in a network element of the second core network.

Step 505: the PCF obtains third information according to the first information and the second information, the PCF sends policy information to the AMF, the first policy information comprises the first information and the third information, the first policy information comprises at least one third PSI and policy segmentation content corresponding to the at least one third PSI, the policy segmentation content corresponding to the at least one third PSI is empty (empty), or the third information comprises at least one third PSI, and the third information does not comprise the policy segmentation content corresponding to the at least one third PSI; the at least one third PSI is included in the second information and not included in the first information.

Policy information is transmitted between the PCF and the UE via a terminal policy container (UE Policy Container), so that the policy information may also be referred to as a terminal policy container.

Optionally, the PCF generates ANDSP based on the information obtained from the UDR whether ANDSP is supported or not, and sends it to the UE. For example, when UE support ANDSP is obtained from UDR, then ANDSP is generated; when the UE does not support ANDSP obtained from the UDR, then ANDSP is not generated.

For example: when the first information generated by the PCF comprises PSI-1, PSI-2 and PSI-5; when the second packet PSI-1, PSI-2, PSI-3, PSI-4 is obtained from the UDR, then the third information obtained by the PCF includes PSI-3 and PSI-4.

The first policy information sent by the PCF to the UE includes PSI-1, PSI-2, PSI-3, PSI-4, PSI-5. Wherein PSI-1, PSI-2, PSI-5 corresponds to normal UE policy section contents, UE policy sectioncontents corresponding to PSI-3 and PSI-4 is an empty, or UE policy section contents corresponding to PSI-3 and PSI-4 is not included in the first policy information.

It should be noted that, the generation process of the first information and the acquisition process of the second information are not sequential. For example, the first information may be regenerated after the second information is received.

Step 506: the AMF replies to the UE with a registration accept (REGISTER ACCEPT) message.

Optionally, the registration acceptance message includes first information and third information.

Embodiment two:

the UE is handed over from the base station 1 to the base station 2 in the connected state, and changes from other AMFs to the AMFs in fig. 6 during the handover.

Referring to fig. 6, the specific steps are as follows:

step 601 to step 602: the same as steps 501-502 shown in fig. 5.

Step 603: in the case where the PCF receives the terminal policy control creation request that does not include UE Policy Container, the PCF generates first information including at least one first PSI and policy-segment contents corresponding to the at least one first PSI, and the PCF saves the first information to the UDR through a data management creation request (e.g., nudr _dm_create request) message.

Step 604: the UDR replies to the data management creation response (e.g., nudr _dm_create response) message.

Step 605: the PCF includes UE Policy Container in a response message (e.g., npcf _ UEPolicyControl Create response) sent to the AMF, and includes UE Policy Container generated first information and fourth information, where the fourth information is used to instruct the UE to save only the first information, that is, to delete policy information saved before, or to instruct the UE to delete other PSI except at least one first PSI included in the first information locally saved and policy section contents corresponding to the other PSI.

Optionally, the method may be used to instruct the UE to delete other PSI except at least one first PSI contained in the first information stored locally and policy segment content corresponding to the other PSI, or may be understood as being used to instruct the UE to delete policy segments corresponding to other PSI except at least one first PSI contained in the first information stored locally.

Step 606: the AMF sends a registration accept message to the UE, optionally including the first information and the fourth information.

Optionally, the UE stores only the first information according to the fourth information; or updating the stored policy information by using the content contained in UE Policy Container, and deleting other PSIs except at least one first PSI contained in the first information stored locally and the policy segmentation content corresponding to the other PSIs.

Optionally, deleting other PSI except at least one first PSI and policy segment content corresponding to the other PSI included in the first information stored locally may also be understood as deleting policy segments corresponding to other PSI except at least one first PSI included in the first information stored locally.

For example, the policy information locally stored by the UE includes PSI-1, PSI-2, PSI-3, PSI-4, and the first information received by the UE includes PSI-1, PSI-2, PSI-5.

The UE deletes the original stored strategy information according to the fourth information, and stores PSI-1, PSI-2, PSI-5 and UE policy section content corresponding to PSI-1, PSI-2, PSI-5; or alternatively

And the UE updates the contents of the PSI-1 and the PSI-2 according to the fourth information, newly adds the contents of the PSI-5, and deletes the PSI-3 and the PSI-4 and UE policy section content corresponding to the PSI-3 and the PSI-4.

Deleting the PSI-3 and PSI-4 and its PSI-3, PSI-4 corresponding UE policy section content may also be understood as deleting the PSI-3 and PSI-4 corresponding UE policy section.

Embodiment III:

Referring to fig. 7, the specific steps are as follows:

steps 701-704: the same as steps 601-604 in fig. 6.

Step 705: the PCF comprises first policy information in a response message sent to the AMF, wherein the first policy information comprises first information, a fourth PSI and policy segmentation contents corresponding to the fourth PSI, and the policy segmentation contents corresponding to the fourth PSI are null, or the first policy information comprises the first information and the fourth PSI, and the fourth PSI is other PSI except at least one first PSI contained in the first information;

optionally, the first policy information includes first information and a fourth PSI, which may be understood that the first policy information does not include policy segment contents corresponding to the fourth PSI.

Step 706: the AMF sends a registration acceptance message to the UE, wherein the registration acceptance message contains the first policy information including the first information, the fourth PSI and the policy segmentation content corresponding to the fourth PSI, and the policy segmentation content corresponding to the fourth PSI is null or the first policy information includes the first information and the fourth PSI.

For example: the policy information stored locally by the UE comprises PSI-1, PSI-2, PSI-3, PSI-4, and policy segment contents corresponding to the PSI-1, PSI-2, PSI-3 and PSI-4, and the first information generated by the PCF comprises PSI-1, PSI-2, PSI-5, and policy segment contents corresponding to the PSI-1, PSI-2 and PSI-5;

The UE receives the first policy information including PSI-1 to PSI-8, wherein policy sectioncontent corresponding to PSI-1, PSI-2, and PSI-5 is normal content, policy sectioncontents corresponding to other PSI (i.e., PSI-3, PSI-4, PSI-6, PSI-7, and PSI-8) is empty or policy section content corresponding to other PSI is not included in the first policy information.

The UE only saves PSI-1, PSI-2, PSI-5 and their corresponding policy section content, deletes other PSIs and other PSI corresponding policy section content, namely deletes PSI-3, PSI-4 and PSI-3, PSI-4 corresponding policy sectioncontent. Deleting policy section content other PSI and other PSI correspondences can also be understood as deleting policy sections corresponding to other PSI.

Referring to fig. 8, an embodiment of the present application provides an information transmission apparatus, which is applied to a first core network device, where the first core external network device includes, but is not limited to: PCF, apparatus 800 comprises:

A first generating module 801, configured to generate first information, where the first information includes at least one first PSI and policy segment content corresponding to the at least one first PSI;

A first sending module 802, configured to send policy information to a terminal, where the first policy information includes the first information, and the first policy information is used to update policy information stored by the terminal.

In one embodiment of the present application, the apparatus 800 further comprises:

A first obtaining module, configured to obtain second information from a second core network element, where the second information includes at least one second PSI of the terminal and policy segmentation content corresponding to the at least one second PSI, where the second PSI is stored in the second core network element;

The determining module is used for obtaining third information according to the first information and the second information;

the first policy information further includes the third information, where the third information includes at least one third PSI and policy segmentation content corresponding to the at least one third PSI, and the policy segmentation content corresponding to the at least one third PSI is null, or the third information includes at least one third PSI, and the third information does not include the policy segmentation content corresponding to the at least one third PSI; the at least one third PSI is included in the second information and not included in the first information.

a second obtaining module, configured to obtain information for indicating whether the terminal supports ANDSP from the second core network element;

A second generating module, configured to generate ANDSP by the first core network element in a case that the terminal supports ANDSP;

and the second sending module is used for sending ANDSP to the terminal.

(1) The terminal stores the first information;

A third acquisition module configured to acquire a fourth PSI, the fourth PSI being other PSI than at least one first PSI included in the first information;

In one embodiment of the present application, the first sending module 802 is further configured to: and generating first information under the condition that the first core network element receives the request message which does not contain PSI.

The device provided by the embodiment of the application can realize each process realized by the embodiment of the method of fig. 3 and achieve the same technical effects, and in order to avoid repetition, the description is omitted here.

Referring to fig. 9, an embodiment of the present application provides an information transmission apparatus, applied to a terminal, where the apparatus 900 includes:

A first receiving module 901, configured to receive first policy information sent by a first core network element, where the first policy information includes first information, and the first information includes at least one first PSI and policy segmentation content corresponding to the at least one first PSI;

And an updating module 902, configured to update the stored policy information according to the first policy information.

The update module 902 is further configured to: and deleting the fifth PSI and the strategy segmentation content corresponding to the fifth PSI under the condition that the terminal stores the fifth PSI which is the same as the at least one third PSI.

In one embodiment of the application, the apparatus further comprises:

And the second receiving module is configured to receive ANDSP sent by the first core network element when the terminal supports the access network service discovery and selection policy ANDSP.

The update module 902 is further configured to: and deleting other PSIs except at least one first PSI stored locally and the policy segmentation content corresponding to the other PSIs.

In one embodiment of the present application, the first policy information further includes a fourth PSI and policy sectional contents corresponding to the fourth PSI, the policy sectional contents are null, or the first policy information further includes a fourth PSI, the first policy information does not include the policy sectional contents corresponding to the fourth PSI, and the fourth PSI is other PSI except at least one first PSI included in the first information;

The update module 902 is further configured to: and deleting the sixth PSI and the strategy segmentation content corresponding to the sixth PSI under the condition that the terminal stores a sixth PSI which is the same as the fourth PSI.

The device provided by the embodiment of the application can realize each process realized by the embodiment of the method of fig. 4 and achieve the same technical effects, and in order to avoid repetition, the description is omitted here.

Fig. 10 is a schematic diagram of a hardware structure of a terminal for implementing an embodiment of the present application. The terminal 1000 includes, but is not limited to: at least some of the components of the radio frequency unit 1001, the network module 1002, the audio output unit 1003, the input unit 1004, the sensor 1005, the display unit 1006, the user input unit 1007, the interface unit 1008, the memory 1009, and the processor 1000, etc.

Those skilled in the art will appreciate that terminal 1000 can also include a power source (e.g., a battery) for powering the various components, which can be logically connected to processor 1000 by a power management system so as to perform functions such as managing charge, discharge, and power consumption by the power management system. The terminal structure shown in fig. 10 does not constitute a limitation of the terminal, and the terminal may include more or less components than shown, or may combine some components, or may be arranged in different components, which will not be described in detail herein.

It should be appreciated that in embodiments of the present application, the input unit 1004 may include a graphics processing unit (GraphicsProcessing Unit, GPU) 10041 and a microphone 10042, where the graphics processor 10041 processes image data of still pictures or video obtained by an image capturing device (e.g., a camera) in a video capturing mode or an image capturing mode. The display unit 1006 may include a display panel 10061, and the display panel 10061 may be configured in the form of a liquid crystal display, an organic light emitting diode, or the like. The user input unit 1007 includes at least one of a touch panel 10071 and other input devices 10072. The touch panel 10071 is also referred to as a touch screen. The touch panel 10071 can include two portions, a touch detection device and a touch controller. Other input devices 10072 may include, but are not limited to, a physical keyboard, function keys (e.g., volume control keys, switch keys, etc.), a trackball, a mouse, a joystick, and so forth, which are not described in detail herein.

In the embodiment of the present application, after receiving downlink data from a network side device, the radio frequency unit 1001 may transmit the downlink data to the processor 1000 for processing; in addition, the radio frequency unit 1001 may send uplink data to the network side device. In general, the radio frequency unit 1001 includes, but is not limited to, an antenna, an amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like.

The memory 1009 may be used to store software programs or instructions and various data. The memory 1009 may mainly include a first memory area storing programs or instructions and a second memory area storing data, wherein the first memory area may store an operating system, application programs or instructions (such as a sound playing function, an image playing function, etc.) required for at least one function, and the like. Further, the memory 1009 may include volatile memory or nonvolatile memory, or the memory 1009 may include both volatile and nonvolatile memory. The nonvolatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable EPROM (EEPROM), or a flash Memory. The volatile memory may be random access memory (Random Access Memory, RAM), static random access memory (STATIC RAM, SRAM), dynamic random access memory (DYNAMIC RAM, DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate Synchronous dynamic random access memory (Double DATA RATE SDRAM, DDRSDRAM), enhanced Synchronous dynamic random access memory (ENHANCED SDRAM, ESDRAM), synchronous link dynamic random access memory (SYNCH LINK DRAM, SLDRAM), and Direct random access memory (DRRAM). Memory 1009 in embodiments of the application includes, but is not limited to, these and any other suitable types of memory.

Processor 1000 may include one or more processing units; optionally, the processor 1000 integrates an application processor that primarily processes operations involving an operating system, user interface, application programs, etc., and a modem processor that primarily processes wireless communication signals, such as a baseband processor. It will be appreciated that the modem processor described above may not be integrated into the processor 1000.

The terminal provided by the embodiment of the present application can implement each process implemented by the embodiment of the method of fig. 4, and achieve the same technical effects, and in order to avoid repetition, a detailed description is omitted here.

Referring to fig. 11, fig. 11 is a block diagram of a network side device to which the embodiment of the present invention is applied, and as shown in fig. 11, a communication device 1100 includes: a processor 1101, a transceiver 1102, a memory 1103 and a bus interface, wherein the processor 1101 may be responsible for managing the bus architecture and general processing. The memory 1103 may store data used by the processor 1101 in performing operations.

In one embodiment of the present invention, the communication device 1100 further comprises: a program stored in the memory 1103 and executable on the processor 1101, which when executed by the processor 1101, implements the steps of the method shown in fig. 3 above.

In fig. 11, a bus architecture may comprise any number of interconnecting buses and bridges, with various circuits of the one or more processors, as represented by the processor 1101, and the memory, as represented by the memory 1103, being linked together. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, power management circuits, etc., which are well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The transceiver 1102 may be a number of elements, i.e., including a transmitter and a receiver, providing a means for communicating with various other apparatus over a transmission medium.

As shown in fig. 12, the embodiment of the present application further provides a communication device 1200, including a processor 1201 and a memory 1202, where the memory 1202 stores a program or an instruction that can be executed on the processor 1201, for example, when the communication device 1200 is a terminal, the program or the instruction is executed by the processor 1201 to implement each step of the embodiment of the method of fig. 4, and when the communication device 1200 is a network side device, the program or the instruction is executed by the processor 1201 to implement each step of the embodiment of the method of fig. 3 and achieve the same technical effect, which is not repeated herein.

The embodiment of the present application further provides a readable storage medium, where a program or an instruction is stored, where the program or the instruction implements the method of fig. 3 or fig. 4 and the processes of the foregoing embodiments when executed by a processor, and the same technical effects can be achieved, so that repetition is avoided, and no further description is given here.

Wherein the processor is a processor in the terminal described in the above embodiment. The readable storage medium includes computer readable storage medium such as computer readable memory ROM, random access memory RAM, magnetic or optical disk, etc.

The embodiment of the application further provides a chip, the chip includes a processor and a communication interface, the communication interface is coupled to the processor, and the processor is configured to run a program or instructions, implement the processes of the embodiments of the methods shown in fig. 3 or fig. 4 and described above, and achieve the same technical effects, so that repetition is avoided, and no further description is given here.

It should be understood that the chips referred to in the embodiments of the present application may also be referred to as system-on-chip chips, or the like.

The embodiments of the present application further provide a computer program/program product stored in a storage medium, where the computer program/program product is executed by at least one processor to implement the processes shown in fig. 3 or fig. 4 and described above in the embodiments of the methods, and achieve the same technical effects, so that repetition is avoided and detailed description is omitted herein.

The embodiment of the application also provides a communication system, which comprises a terminal and a network side device, wherein the terminal is used for executing the processes of the embodiments of the method shown in fig. 4 and described above, and the network side device is used for executing the processes of the embodiments of the method shown in fig. 3 and described above, and the same technical effects can be achieved, and for avoiding repetition, the description is omitted here.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of the present application is not limited to performing the functions in the order shown or discussed, but may also include performing the functions in a substantially simultaneous manner or in an opposite order depending on the functions involved, e.g., the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a computer software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method according to the embodiments of the present application.

The embodiments of the present application have been described above with reference to the accompanying drawings, but the present application is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present application and the scope of the claims, which are to be protected by the present application.

Claims

1. An information transmission method, comprising:

2. The method according to claim 1, wherein the method further comprises:

The first core network element acquires second information from a second core network element, wherein the second information comprises at least one second PSI of the terminal and strategy segmentation content corresponding to the at least one second PSI;

3. The method according to claim 1, wherein the method further comprises:

The first core network element obtains information for indicating whether the terminal supports an access network service discovery and selection policy ANDSP from a second core network element;

And the first core network element sends ANDSP to the terminal.

4. The method of claim 1, wherein the step of determining the position of the substrate comprises,

The first policy information further includes: fourth information indicating at least one of:

The terminal stores the first information;

And deleting other PSIs except at least one first PSI contained in the first information and policy segmentation contents corresponding to the other PSIs by the terminal.

5. The method according to claim 1, wherein the method further comprises:

The first policy information further comprises a fourth PSI and policy segmentation content corresponding to the fourth PSI, wherein the policy segmentation content corresponding to the fourth PSI is empty; or the first policy information further includes the fourth PSI, and the first policy information does not include the policy segmentation content corresponding to the fourth PSI.

6. The method according to any of claims 1 to 5, wherein the first core network element generates first information comprising:

and generating first information by the first core network element under the condition that the first core network element receives the request message which does not contain PSI.

7. The method of claim 6, wherein the request message comprises a terminal policy control creation request message.

8. The method according to any of claims 1 to 5, wherein the first core network element comprises a policy control function, PCF.

9. A method according to claim 2 or 3, characterized in that the second core network element comprises a unified data repository UDR.

10. An information transmission method, comprising:

the method comprises the steps that a terminal receives first strategy information sent by a first core network element, wherein the first strategy information comprises first information, the first information comprises at least one first strategy segmentation identifier PSI and strategy segmentation content corresponding to the at least one first PSI, and the first information is generated by the first core network element;

11. The method of claim 10, wherein the step of determining the position of the first electrode is performed,

The first policy information further includes third information, where the third information includes at least one third PSI and policy segmentation content corresponding to the at least one third PSI, and the policy segmentation content corresponding to the at least one third PSI is null, or the third information includes at least one third PSI, and the third information does not include the policy segmentation content corresponding to the at least one third PSI;

12. The method of claim 11, wherein the method further comprises:

13. The method of claim 10, wherein the step of determining the position of the first electrode is performed,

The first policy information further includes: fourth information indicating at least one of: the terminal stores the first information; the terminal deletes other PSIs except at least one first PSI contained in the first information and policy segmentation contents corresponding to the other PSIs;

And deleting other PSIs except at least one first PSI stored locally and policy segmentation contents corresponding to the other PSIs by the terminal.

14. The method of claim 10, wherein the step of determining the position of the first electrode is performed,

The first policy information further includes a fourth PSI and policy sectional contents corresponding to the fourth PSI, where the policy sectional contents corresponding to the fourth PSI are null, or the first policy information further includes a fourth PSI, where the policy sectional contents corresponding to the fourth PSI are not included in the first policy information, and the fourth PSI is other PSI except at least one first PSI included in the first information;

15. The method according to any of the claims 7 to 14, wherein the first core network element comprises a policy control function, PCF.

16. An information transmission apparatus, comprising:

17. The apparatus of claim 16, wherein the apparatus further comprises:

The first policy information further includes third information, where the third information includes at least one third PSI and policy segmentation content corresponding to the at least one third PSI, and the policy segmentation content corresponding to the at least one third PSI is null, or the third information includes at least one third PSI, and the third information does not include the policy segmentation content corresponding to the at least one third PSI.

18. The apparatus of claim 16, wherein the apparatus further comprises:

A second obtaining module, configured to obtain information for indicating whether the terminal supports ANDSP from a second core network element;

A second generating module, configured to generate ANDSP in a case that the terminal supports ANDSP;

and the second sending module is used for sending ANDSP to the terminal.

19. The apparatus of claim 16, wherein the device comprises a plurality of sensors,

The terminal stores the first information;

20. The apparatus of claim 16, wherein the apparatus further comprises:

the first policy information further comprises a fourth PSI and policy segmentation content corresponding to the fourth PSI, wherein the policy segmentation content is empty; or the first policy information further includes the fourth PSI, and the first policy information does not include the policy segmentation content corresponding to the fourth PSI.

21. An information transmission apparatus, comprising:

22. The apparatus of claim 21, wherein the device comprises a plurality of sensors,

The first policy information further includes third information, where the third information includes at least one third PSI and policy segmentation content corresponding to the at least one third PSI, the policy segmentation content corresponding to the at least one third PSI is null, or the third information includes at least one third PSI, and the third information does not include corresponding policy segmentation content;

The update module is further to: and deleting the fifth PSI and the strategy segmentation content corresponding to the fifth PSI locally under the condition that the terminal stores the fifth PSI which is the same as the at least one third PSI.

23. The apparatus of claim 22, wherein the apparatus further comprises:

24. The apparatus of claim 21, wherein the device comprises a plurality of sensors,

the update module is further to: and deleting other PSIs except at least one first PSI stored locally and the policy segmentation content corresponding to the other PSIs.

25. The apparatus of claim 21, wherein the device comprises a plurality of sensors,

The first policy information further includes a fourth PSI and policy sectional content corresponding to the fourth PSI, where the policy sectional content is null, or the first policy information further includes a fourth PSI, where the first policy information does not include the policy sectional content corresponding to the fourth PSI, and the fourth PSI is other PSI except at least one first PSI included in the first information;

The update module is further to: and deleting the sixth PSI and the strategy segmentation content corresponding to the sixth PSI under the condition that the terminal stores a sixth PSI which is the same as the fourth PSI.

26. A communication device comprising a processor, a memory and a program or instruction stored on the memory and executable on the processor, which when executed by the processor implements the steps of the method of any of claims 1 to 15.

27. A readable storage medium, characterized in that it stores thereon a program or instructions which, when executed by a processor, implement the steps of the method according to any of claims 1 to 15.