CN112543172A

CN112543172A - IMS calling method, terminal and network function

Info

Publication number: CN112543172A
Application number: CN201910900941.3A
Authority: CN
Inventors: 谢振华
Original assignee: Vivo Mobile Communication Co Ltd
Current assignee: Vivo Mobile Communication Co Ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2021-03-23
Anticipated expiration: 2039-09-23
Also published as: WO2021057776A1; CN112543172B

Abstract

The embodiment of the invention provides an IMS calling method, a terminal and a network function, wherein the method comprises the following steps: sending an IMS call message, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by the first terminal; wherein the first terminal has registered to IMS prior to sending the IMS call message. The embodiment of the invention can improve the IMS calling performance in the communication system.

Description

IMS calling method, terminal and network function

Technical Field

The present invention relates to the field of communications technologies, and in particular, to an internet protocol Multimedia Subsystem (IMS) calling method, a terminal, and a network function.

Background

Some communication systems support IMS and in these communication systems, before sending IMS information, the terminal needs to activate or establish a connection with the mobile network to send IMS information over the connection. In addition, in some practical applications, different terminals may exist, or the IMS functions supported by the terminals and the network are inconsistent, so that the network may adopt a processing mode supported by all the terminals in the IMS call process, so that the IMS call performance in the communication system is relatively low.

Disclosure of Invention

The embodiment of the invention provides an IMS calling method, a terminal and a network function, which aim to solve the problem of low IMS calling performance in a communication system.

In a first aspect, an embodiment of the present invention provides an IMS call method, applied to a first terminal, including:

sending an IMS call message, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by the first terminal;

wherein the first terminal has registered to IMS prior to sending the IMS call message.

In a second aspect, an embodiment of the present invention provides an IMS call method, applied to a second terminal, including:

receiving an IMS call message, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by a first terminal initiating the IMS call message;

sending an IMS ringing message, wherein the IMS ringing message carries media information;

wherein the second terminal has registered to IMS prior to receiving the IMS call message.

In a third aspect, an embodiment of the present invention provides an IMS call method, applied to a first network function, including:

receiving an IMS call message from a first terminal, or sending the IMS call message to a second terminal;

and sending a policy authorization creation request to a policy control function, wherein the policy authorization creation request carries media parameters, and the first media parameters are obtained through the IMS call message.

In a fourth aspect, an embodiment of the present invention provides a terminal, where the terminal is a first terminal, and the terminal includes:

a sending module, configured to send an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment method supported by the first terminal;

In a fifth aspect, an embodiment of the present invention provides a terminal, where the terminal is a second terminal, and the terminal includes:

a receiving module, configured to receive an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment method supported by a first terminal that initiates the IMS call message;

a sending module, configured to send an IMS ringing message, where the IMS ringing message carries media information;

In a sixth aspect, an embodiment of the present invention provides a network function, where the network function is a first network function, and the network function includes:

a transmission module, configured to receive an IMS call message from a first terminal, or send the IMS call message to a second terminal;

a sending module, configured to send a policy authorization creation request to a policy control function, where the policy authorization creation request carries media parameters, and the media parameters are obtained through the IMS call message.

In a seventh aspect, an embodiment of the present invention provides a terminal, where the terminal is a first terminal, and the terminal includes: the present invention also provides an IMS call method according to the first aspect of the embodiments of the present invention, wherein the IMS call method further comprises a step of storing the IMS call information in a memory, and a step of executing the IMS call information in the memory.

In an eighth aspect, an embodiment of the present invention provides a terminal, where the terminal is a second terminal, and the terminal includes: a memory, a processor and a program stored on the memory and executable on the processor, wherein the program when executed by the processor implements the steps of the IMS call method provided by the second aspect of the embodiment of the present invention.

In a ninth aspect, an embodiment of the present invention provides a network function, where the network function is a first network function, and the network function includes: a memory, a processor and a program stored on the memory and executable on the processor, wherein the program when executed by the processor implements the steps of the IMS call method provided in the third aspect of the embodiment of the present invention.

In a tenth aspect, an embodiment of the present invention provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and the computer program, when executed by a processor, implements the steps in the IMS call method provided in the first aspect of the embodiment of the present invention, or the computer program, when executed by the processor, implements the steps in the IMS call method provided in the second aspect of the embodiment of the present invention, or the computer program, when executed by the processor, implements the steps in the IMS call method provided in the third aspect of the embodiment of the present invention.

In the embodiment of the invention, an IMS call message is sent, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by a first terminal; wherein the first terminal has registered to IMS prior to sending the IMS call message. In this way, the IMS session establishment method supported by the first terminal can be indicated by the first indication information, so that the network can perform processing by using the IMS session establishment method supported by the first terminal, thereby improving the IMS call performance in the communication system.

Drawings

Fig. 1 is a block diagram of a network system to which an embodiment of the present invention is applicable;

fig. 2 is a flowchart of an IMS call method according to an embodiment of the present invention;

fig. 3 is a flowchart of another IMS call method provided in an embodiment of the present invention;

fig. 4 is a flowchart of another IMS call method provided in an embodiment of the present invention;

fig. 5 is a schematic diagram of an IMS call method according to an embodiment of the present invention;

fig. 6 is a schematic diagram of another IMS call method provided in an embodiment of the present invention;

fig. 7 is a schematic diagram of another IMS call method provided in an embodiment of the present invention;

fig. 8 is a schematic diagram of another IMS call method provided in an embodiment of the present invention;

fig. 9 is a structural diagram of a terminal according to an embodiment of the present invention;

fig. 10 is a block diagram of another terminal provided in an embodiment of the present invention;

fig. 11 is a block diagram of another terminal provided in an embodiment of the present invention;

FIG. 12 is a block diagram of a network function provided by an embodiment of the present invention;

FIG. 13 is a block diagram of another network function provided by an embodiment of the present invention;

fig. 14 is a block diagram of another terminal provided in an embodiment of the present invention;

fig. 15 is a block diagram of another network function provided in an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terms "comprises," "comprising," or any other variation thereof, in the description and claims of this application, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the use of "and/or" in the specification and claims means that at least one of the connected objects, such as a and/or B, means that three cases, a alone, B alone, and both a and B, exist.

In the embodiments of the present invention, words such as "exemplary" or "for example" are used to mean serving as examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "e.g.," an embodiment of the present invention is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present concepts related in a concrete fashion.

Embodiments of the present invention are described below with reference to the accompanying drawings. The IMS calling method, the terminal and the network function provided by the embodiment of the invention can be applied to a wireless communication system. The wireless communication system may be a 5G system, an Evolved Long Term Evolution (LTE) system, a subsequent Evolution communication system, or the like.

Referring to fig. 1, fig. 1 is a structural diagram of a network system applicable to the embodiment of the present invention, and as shown in fig. 1, the network system includes a terminal 11, a first network element 12, and a second network element 13, where the terminal 11 may communicate with the first network element 12, the second network element 12 may communicate with the terminal 11, and may also communicate with the second network element 13, and further, the terminal 11 may also communicate with the second network element 13 through the first network element 11.

The terminal 11 may be a User Equipment (UE) or other terminal-side Equipment, for example: a Mobile phone, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), a Wearable Device (Wearable Device), a smart car, a vehicle-mounted Device, or a robot, and other terminal-side devices, it should be noted that a specific type of a terminal is not limited in the embodiment of the present invention.

The first Network element 12 may be a Radio Access Network (RAN) Network element, which may include but is not limited to at least one of the following: radio Access Network equipment, Radio Access Network nodes, Radio Access Network functions, Radio Access Network units, Third Generation Partnership Project (3 GPP) Radio Access Networks, Non-3GPP Radio Access Networks, Centralized Units (CUs), Distributed Units (DUs), base stations, evolved Node bs (enbs), 5G base stations (gnbs), Radio Network controllers (Radio Network controllers, RNCs), base stations (nodebs), Non-3GPP interworking functions (Non-3GPP Inter Working Function, N3IWF), Access control (Access Controller, AC) nodes, Access Point (AP) devices, or Wireless Local Area Network (WLAN) nodes.

The second Network element 13 may be a Core Network (CN) Network element that may include, but is not limited to, at least one of the following: core network equipment, core network nodes, core network functions, Mobility Management Entity (MME), Access Management Function (AMF), IMS Control Function (IMS Control Function, IMSCF), Session Management Function (Session Management Function, SMF), User Plane Function (User Plane Function, UPF), serving gateway (serving GW, SGW), PDN gateway (PDN gateway), Policy Control Function (Policy Control Function, PCF), Proxy IMS Session Control Function (P-CSC), Policy and Charging Rules Function (Policy and Charging Rules Function, PCRF), Home Subscriber Server (Home Subscriber Server, HSS), Application Function (Application Function, AF), and the like.

It should be noted that the specific types of the terminal 11, the first network element 12, and the second network element 13 are not limited in the embodiment of the present invention.

Referring to fig. 2, fig. 2 is a flowchart of an IMS call method according to an embodiment of the present invention, where the method is applied to a first terminal, and as shown in fig. 2, the method includes the following steps:

step S201, an IMS call message is sent, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by the first terminal;

The sending of the IMS call message may be in an idle state or an inactive state, and of course, the sending may also be in a connected state. And the IMS call message may be an IMS call setup request, such as a send SIP INVITE message, or other IMS call related message.

It should be noted that, in the IMS call method provided in the embodiment of the present invention, since the network function may execute the relevant operation of the IMS call when the response of the second terminal to the IMS call request is not received, for example: the method for establishing the IMS call can be called as a fast IMS call method, and an IMS session establishment mode in the embodiment of the invention can be used for establishing the fast IMS session. That is, the first indication information may be used to indicate fast IMS session establishment supported by the first terminal. So that the network can process the IMS call message in a fast IMS session setup manner.

In the embodiment of the present invention, the first terminal may have registered to the IMS before sending the IMS call message, where the first terminal establishes a connection with a mobile network to initiate an IMS registration process to register to the IMS in a connected state. For example: the first terminal sends the IMS call message in an idle state, but before the terminal enters the idle state, the first terminal registers to the IMS in a connected state.

Because the first terminal is registered to the IMS before sending the IMS call message, the IMS registration process does not need to be initiated before sending the IMS call message, so that the time for sending the IMS call by the terminal is reduced.

In the embodiment of the present invention, the first indication information carried in the IMS call message indicates the IMS session establishment method supported by the first terminal through the above steps, so that the network can use the IMS session establishment method supported by the first terminal to perform processing, and the network is prevented from using a uniform processing method to perform processing, so as to improve the IMS call performance in the communication system. For example: the first terminal supports fast IMS session establishment, so that the network can adopt the fast IMS session establishment to process the IMS call message, and does not adopt an unrefreshed processing mode to process the IMS call message sent by the first terminal.

The first indication information may also be referred to as a Mobile Originated (MO) indication.

The sending of the IMS call message may be sending an IMS call message to the network side, for example: the CN network element, such as the MS call message, may pass through the base station of the mobile network and the transparent forwarding of the UPF to reach the P-CSCF in the IMS network, and the P-CSCF forwards the message to the second terminal (i.e., the target user) through the IMS network.

Optionally, the terminal sends a Non-access stratum (NAS) request, where the NAS request carries the IMS call message.

In this embodiment, it is possible to implement the IMS call message transmission by NAS request. Since sending the NAS request may be sent without activating or establishing a connection with the mobile network, it may now be supported that a connection with the mobile network may not be activated or established before sending the IMS call message, in order to reduce the duration of the IMS call.

For example: the NAS request message may include: a service request or a Protocol Data Unit (PDU) session update request.

The Service Request may be a Service Request (Service Request) message or other messages for activating or establishing a wireless air interface connection.

Therefore, the first terminal can send the IMS call message through the service request or the PDU session update request in an idle state, so that the multiplexing of the IMS call message and the service request or the PDU session update request is realized, and the time length for sending the IMS call is reduced.

Optionally, before sending the IMS call message, the method further includes:

and receiving second indication information from a network, wherein the second indication information is used for indicating an IMS session establishment mode supported by the network.

The second indication information received from the network may be indication information sent by the terminal receiving a CN network element, for example, indication information sent by a P-CSCF is received to indicate an IMS session establishment mode supported by the P-CSCF.

In addition, the second indication information may indicate that the IMS session establishment method supported by the network is fast IMS session establishment.

Of course, if a network function does not support fast IMS session establishment, the network function may not send the second indication information to indicate that it does not support fast IMS session establishment.

In the above embodiment, since the first terminal receives the second indication information, the IMS session establishment method supported by the network can be determined, and the IMS call message can be sent in a corresponding manner according to the actual situation, so as to avoid the transmission waste caused by the inconsistency between the first terminal and the network side.

For example: the terminal may determine that the IMS call message carries the first indication information according to the second indication information. Specifically, if the second indication information network supports fast IMS session establishment and the first terminal also supports fast IMS session establishment, the IMS call message carries the first indication information, so as to implement fast IMS session establishment. Further, the second indication information may indicate, by default, that fast IMS session establishment is supported, so that the first indication information is carried in an IMS call message if the second indication information is received and the first terminal supports fast IMS session establishment. If the second indication information indicates that the network supports fast IMS session establishment but the first terminal does not support fast IMS session establishment, or the network does not send the second indication information to the terminal, or the sent second indication information is used for indicating that the network does not support fast IMS session establishment, the first indication information is not carried in the IMS call message, so that resource waste or transmission errors caused by the fact that the IMS is carried in the IMS call message are avoided.

Referring to fig. 3, fig. 3 is a flowchart of another IMS call method according to an embodiment of the present invention, where the method is applied to a second terminal, and as shown in fig. 3, the method includes the following steps:

step S301, receiving an IMS call message, wherein the IMS call message carries first indication information, and the first indication information is used for indicating an IMS session establishment mode supported by a first terminal initiating the IMS call message;

step S302, an IMS ringing message is sent, and the IMS ringing message carries media information;

The IMS call message may refer to the corresponding description of the embodiment shown in fig. 2, which is not described herein again.

In addition, the received IMS call request message may be an IMS call request message from the first terminal forwarded by the receiving P-CSCF.

Since the IMS call message includes the first indication information, it can be determined that the first terminal supports the IMS call method provided in the embodiment of the present invention, that is, fast IMS session establishment, so that the IMS ringing message carries media information, which is convenient for a network to fast establish an IMS session, so as to improve IMS call performance in a communication system.

The media information may be related information for assisting IMS session establishment, for example: the media information may include at least one of:

media type, session bandwidth, bandwidth of media type, addresses at both ends of the media connection.

The media type may be one or more media types, and the bandwidth of the media type may be a bandwidth of one or more media types. The address of one end of the media connection may be an address of a certain terminal of the media connection related to the IMS call message, such as the address of the first terminal.

The media information can enable a network element (such as a session management function) to reserve resources in advance so as to establish the IMS session quickly.

It should be noted that the second terminal may receive the IMS call message in a connected state, an idle state, or an inactive state, and send an IMS ringing message.

Optionally, before sending the IMS call message, the method further includes:

The second indication information may refer to the second indication information in the embodiment shown in fig. 2, which is not described herein again, and the same beneficial effects may be achieved.

Optionally, the terminal determines, according to the second indication information, that the IMS ringing message carries the media information.

In this embodiment, reference may be made to the second indication information in the embodiment shown in fig. 2, which is not described herein again, and the same beneficial effects may be achieved.

In this embodiment, the IMS ringing message may carry media information, so that the network can establish an IMS session quickly, thereby improving IMS call performance in the communication system.

Referring to fig. 4, fig. 4 is a flowchart of another IMS call method according to an embodiment of the present invention, where the method is applied to a first network function, and as shown in fig. 4, the method includes the following steps:

step S401, receiving an IMS call message from a first terminal, or sending the IMS call message to a second terminal;

step S402, sending a policy authorization establishing request to a policy control function, wherein the policy authorization establishing request carries media parameters, and the media parameters are obtained through the IMS call message.

Wherein, the first network function may be a CN network element, for example: a P-CSCF.

The IMS call message may refer to the corresponding description of the embodiment shown in fig. 2, and is not described herein again.

In addition, in an embodiment of sending the IMS call message to the second terminal, the IMS call message may be that the first network function forwards the IMS call message received from the first terminal to the second terminal, or the first network function sends the IMS call message to the second terminal based on the received IMS message sent by another device or function, which of course does not exclude that the first network function sends the IMS call message to the second terminal actively.

It should be further noted that the receiving of the IMS call message from the first terminal may be performed before the sending of the first policy authorization creation request to the policy control function, and the sending of the IMS call message to the second terminal may be performed before or after the sending of the first policy authorization creation request to the policy control function, or performed simultaneously, where the drawing illustrates the sending of the IMS call message first and then the sending of the first policy authorization creation request.

In addition, the media parameter may be a media parameter for creating a mobile network connection that meets the requirements of the IMS session, for example, the media parameter includes at least one of a bandwidth, an address at one end of the media connection, and the like for the IMS session.

The media parameter may be obtained through the IMS call message and generated according to content carried in the IMS call message, for example, the IMS call message may carry media information, such as at least one of: media type, session bandwidth, bandwidth of media type, address of one end of media connection. Of course, in the case that the IMS call message does not carry media information, the first network function may also obtain the media parameter through the IMS call message, for example: the first terminal is determined by itself or by means of an IMS call message and the parameters like the address are obtained from the context of the first terminal.

In this embodiment, through the above steps, before a response of the second terminal to the IMS call message is not received, the policy authorization creation request may be sent to the policy control function, so that an IMS session may be quickly established, thereby improving IMS call performance in the communication system.

In addition, after sending the policy authorization creation request to the policy control function, the policy control function will respond to the policy authorization creation request. It should be noted that, in the embodiment of the present invention, a manner in which the policy control function responds to the policy authorization creation request is not limited, and a response manner defined in the protocol or defined in a subsequent protocol version may be adopted. Further, the first network function may further receive a policy authorization creation response, where the response may indicate that the policy control function has successfully responded to the policy authorization creation request.

Optionally, after sending the IMS call message to the second terminal, the method further includes:

and receiving an IMS ringing message from the second terminal, wherein the IMS ringing message carries media information.

The IMS ringing message may refer to the corresponding description of the embodiment shown in fig. 3, which is not described herein again, and the same beneficial effects may be achieved.

Optionally, after receiving the IMS ringing message from the second terminal, the method further includes:

and receiving a resource reservation completion notification message sent by a session management function, and forwarding the IMS ringing message.

The resource reservation completion notification message may indicate that the session management function determines that the resource reservation of the IMS call IMS media user plane is completed, so that the IMS ringing message is forwarded after receiving the resource reservation completion notification message sent by the session management function, so as to quickly establish an IMS session.

Optionally, before receiving the IMS call message from the first terminal or before sending the IMS call message to the second terminal, the method further includes:

and sending second indication information to the first terminal or the second terminal, wherein the second indication information is used for indicating an IMS session establishment mode supported by the first network function.

The second indication information may refer to corresponding descriptions of the embodiment shown in fig. 3, which are not described herein again, and the same beneficial effects may be achieved.

In this embodiment, it may be achieved that, before a response to the IMS call message by the second terminal is not received, the policy authorization creation request is sent to the policy control function, so that the IMS session may be quickly established, so as to improve IMS call performance in the communication system.

The following description will be given by taking the first terminal as the UE and the IMS call message as the IMS call setup request:

in an embodiment, the embodiment mainly describes that the terminal initiates IMS call setup through a mobile network, and specifically, as shown in fig. 5, the method includes the following steps:

step 301: the terminal (UE) is in a connected state, and the UE has completed a Registration process in the IMS network, such as initiating a SIP Registration message to the IMS network, forwarding the message through a P-CSCF of the IMS network, and receiving a SIP 200 OK message from the IMS network, which is forwarded through the P-CSCF. The P-CSCF may send an IMS indication to the UE for indicating support for fast establishment of an IMS session, for example, the IMS indication is carried in a registration response message (i.e., the above-mentioned SIP 200 OK message) or other IMS message sent to the UE.

Step 302: the UE initiates an IMS call setup request to the target user, for example, sends SIP INVITE a message, where the message may carry an MO indication to indicate that the IMS session is supported to be quickly established, and the UE may also determine that the received IMS indication in step 301 carries the MO indication in the IMS call setup request.

Step 303: the IMS call establishment request is transparently forwarded to a P-CSCF in the IMS network through a base station of the mobile network and a UPF, and the P-CSCF forwards the request to a target user through the IMS network.

Step 304: the P-CSCF sends a Policy Authorization creation Request, such as sending a Policy Authorization Create Request, to a Policy Control Function (PCF), carrying media parameters, where the media parameters are generated based on media information, and the media parameters are used to Create a mobile network connection that meets IMS session requirements, including media types, and may also include connection address information (i.e., connection address information of the UE, including an IP address and a port number), bandwidth, and the like, and the PCF sends a Policy Authorization creation Response, such as sending a Policy Authorization Create Response, to the P-CSCF.

Step 305: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, carrying Quality of Service (QoS) parameters of the IMS session, such as QoS priority information, bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 306: the SMF sends an N4 interface Session update Request to a User Plane Function (UPF), such as sending an N4Session Modification Request, may carry a rule based on connection address information at a Session connection end (i.e., connection address information of the UE, including an IP address and a port number), and is used for the UPF to process a downlink data packet according to the rule and receive an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF and carrying UPF receive address information.

Step 307: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2message transfer Request, carries the UPF received address information, also carries a PDU Session update Command, for example, a PDU Session Modification Command message, and also carries a QoS parameter for establishing an air interface connection, and the AMF returns a Response to the SMF, for example, sends a Namf _ Communication _ N1N2message transfer Response.

Step 308: the AMF sends an air interface update Request to the base station, for example, sends an N2 Request, which carries parameters for establishing an air interface connection, including QoS parameters for establishing an air interface connection from the SMF and UPF receiving address information, and also carries a PDU session update command.

Step 309: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 310: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 311: the base station sends an air interface update Response to the AMF, for example, sends N2 Response, which carries the receiving address information of the base station.

Step 312: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request, which carries the receiving address information of the base station.

Step 313: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to the user plane function UPF and receives an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 314: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 315: the P-CSCF receives an IMS call establishment response carrying media description information of a terminal of a target user from the target user, such as SIP 183 Progress, or an IMS Ringing message possibly carrying media description information of the terminal of the target user from the target user, such as SIP 180 Ringing, the P-CSCF sends the received IMS call establishment response or IMS Ringing message to the UE, the message is transparently forwarded through UPF and a base station, if the message is an IMS Ringing message, after step 309 or step 310 (the IMS Ringing message may arrive at the UE earlier than step 309 or step 310), the UE plays a reminding sound to remind the user that the IMS call connection establishment is completed, and the target user rings.

The IMS ringing message may arrive earlier than step 309 or 310, and the UE may forward the IMS call request after the P-CSCF receives the IMS call request, so as to send the IMS ringing message to the UE.

Step 316: if the P-CSCF receives the media description information from the terminal of the target user, the P-CSCF sends a Policy Authorization creation Request to a Policy Control Function (PCF), such as sending a Policy Authorization creation Request carrying media parameters of an IMS session, which is used for creating a mobile network connection meeting the requirements of the IMS session, including a media type, address information of two ends of the session connection, and the like, and the PCF sends a Policy Authorization creation Response to the P-CSCF, such as sending a Policy Authorization creation Response.

Step 317: the PCF finds that the Policy information is updated, for example, the connection address information of the opposite end is added, or the media type is reduced, etc., the PCF sends a session management Policy update Request, for example, the SM Policy Association Modification Request is sent, which carries updated IMS session Policy parameters, for example, the connection address information of the opposite end, the remaining QoS priority information after the media type is reduced, the bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, for example, the SM Policy Association Modification Response is sent to the PCF.

Step 318: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2MessageTransfer Request, carries a PDU Session update Command, for example, a PDU Session Modification Command, carries opposite end connection address information, the message forwarding Request also carries updated air interface connection QoS parameters, and the AMF returns a Response to the SMF, for example, sends a Namf _ Communication _ N1N2MessageTransfer Response.

Step 319: the AMF sends an air interface update Request to the base station, such as sending an N2 Request, carrying the updated QoS parameters of the air interface connection from the SMF, and also carrying a PDU session update command.

Step 320: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 321: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 322: the base station sends an air interface update Response to the AMF, such as N2 Response.

Step 323: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request.

Step 324: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Steps 325-327 below exist only if step 315 is responsive to an IMS call.

Step 325: after step 315 and step 309, the UE sends an IMS session resource reservation complete message to the target user through the P-CSCF, for example, sends an SIP PRACK message, the message is transparently forwarded through the base station and the UPF, and the P-CSCF forwards the message to the target user.

Step 326: the UE receives an IMS session resource reservation confirm message, such as a SIP 200 OK message, for the target user.

Step 327: the UE receives an IMS Ringing message of the target user, such as an SIP 180 Ringing message, and plays a reminding sound to prompt the user that the IMS call connection is established and the target user rings.

Step 328: the target user answers the IMS call, the UE receives an IMS session answering message from the target user, such as SIP 200 OK, and the IMS session is connected.

If step 315 is an IMS ringing message and does not carry media description information, the media description information of the terminal of the target user is received only in step 328, that is, steps 316-324 occur after step 328.

In an embodiment, the embodiment mainly describes that the terminal accepts IMS call setup through a mobile network, and specifically, as shown in fig. 6, the method includes the following steps:

step 401: the UE is in a connected state, and the UE has completed a Registration process in the IMS network, such as initiating a SIP Registration message to the IMS network, forwarding the message through a P-CSCF of the IMS network, and receiving a SIP 200 OK message from the IMS network, which is forwarded through the P-CSCF. The P-CSCF may send an IMS indication to the UE for indicating support for fast establishment of an IMS session, for example, the IMS indication is carried in a registration response message (i.e., the above-mentioned SIP 200 OK message) or other IMS message sent to the UE.

Step 402: the P-CSCF receives an IMS session establishment request, such as SIP INVITE message, which may carry an MO indication for indicating support of fast IMS session establishment, forwards the message to the UE of the target user, and the message reaches the UE through the transparent forwarding of the UPF and the base station.

Step 403: the P-CSCF sends a Policy Authorization creation Request to a Policy Control Function (PCF), for example, sends a Policy Authorization creation Request, which carries media parameters, the media parameters are generated based on media description information carried in the IMS session establishment Request, the media parameters are used to Create a mobile network connection that meets the IMS session requirements, include a media type, and may also include connection address information of one end of the session connection (i.e., connection address information of the opposite end, including an IP address and a port number), a bandwidth, and the like, and the PCF sends a Policy Authorization creation Response, for example, sends a Policy Authorization creation Response to the P-CSCF.

Step 404: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, carrying QoS parameters of the IMS session, such as QoS priority information, bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 405: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2message transfer Request, carries UPF received address information, and also carries a PDU Session update Command, for example, a PDU Session update Command, where the PDU Session update Command may carry a rule based on connection address information (i.e., connection address information of the opposite end, including an IP address and a port number) of one end of a Session connection, and is used for the UE to process an uplink data packet according to the rule and also carries a QoS parameter for establishing an air interface connection, and the AMF returns a Response to the SMF, for example, sends a Namf _ Communication _ N1N2message transfer Response.

Step 406: the AMF sends an air interface update Request to the base station, for example, sends an N2 Request, which carries parameters for establishing an air interface connection, including QoS parameters for establishing an air interface connection from the SMF and UPF receiving address information, and also carries a PDU session update command.

Step 407: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 408: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 409: the base station sends an air interface update Response to the AMF, for example, sends N2 Response, which carries the receiving address information of the base station.

Step 410: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request, which carries the receiving address information of the base station.

Step 411: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to a User Plane Function (UPF), and receives an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 412: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 413: after step 411, the IMS media User plane resource reservation of the UE is completed, optionally, the SMF may send a User plane Management event Notification, such as a User plane Management Notification message, to the P-CSCF, and the P-CSCF may determine whether the IMS media User plane resource reservation of the UE is successful according to the message, and determine whether to forward the received IMS ringing message to the calling User according to the message.

Step 414: the UE sends an IMS Ringing message to the calling subscriber, where the message carries media description information (contained in the SDP Answer) of the UE, and the message is transparently forwarded to the P-CSCF through a base station of the mobile network and a UPF of the mobile network, the UE may determine whether to send an SIP 180 Ringing message carrying the SDP Answer according to whether an MO indication is received, the UE may send the IMS Ringing message after step 402, or step 407, or step 408, and the P-CSCF may buffer the IMS Ringing message and forward the IMS Ringing message after step 413.

Step 415: the P-CSCF sends a Policy Authorization creation Request to the Policy control function PCF, such as sending a Policy Authorization Create Request, carrying media parameters of the IMS session, for creating a mobile network connection that meets the IMS session requirements, including a media type, address information of both ends of the session connection, and the like, and the PCF sends a Policy Authorization creation Response to the P-CSCF, such as sending a Policy Authorization Create Response.

Step 416: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, to the SMF, carrying updated IMS session Policy parameters, such as opposite end connection address information, remaining QoS priority information after the media type is reduced, bandwidth, and the like, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 417: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2MessageTransfer Request, carries a PDU Session update Command, for example, a PDU Session Modification Command, the PDU Session update Command carries opposite end connection address information, and the message forwarding Request also carries updated air interface connection QoS parameters.

Step 418: the AMF sends an air interface update Request to the base station, such as sending an N2 Request, carrying the updated QoS parameters of the air interface connection from the SMF, and also carrying a PDU session update command.

Step 419: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 420: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 421: the base station sends an air interface update Response to the AMF, such as N2 Response.

Step 422: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request.

Step 423: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to a user plane function UPF, where the message carries a rule based on connection address information at one end of a Session connection (i.e., connection address information of the UE, including an IP address and a port number), and is used for the UPF to process a downlink data packet according to the rule, and receive an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 424: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 425: the user of the UE answers the IMS call, and the UE sends an IMS session answer message, such as SIP 200 OK, to the calling user, and the IMS session is closed.

In an embodiment, the embodiment mainly describes that the terminal accepts IMS call setup through a mobile network, and specifically, as shown in fig. 7, the method includes the following steps:

step 501: the terminal UE is in an idle state, and the UE has completed a Registration process in the IMS network, for example, initiating a SIP Registration message to the IMS network, forwarding the message through a P-CSCF of the IMS network, and receiving a SIP 200 OK message forwarded through the P-CSCF from the IMS network. The P-CSCF may send an IMS indication to the UE for indicating support for fast establishment of an IMS session, for example, the IMS indication is carried in a registration response message (i.e., the above-mentioned SIP 200 OK message) or other IMS message sent to the UE.

Step 502: the P-CSCF receives an IMS session establishment request, such as SIP INVITE message, which may carry an MO indication for indicating support of fast establishment of an IMS session, forwards the message to the UE of the target user, where the message passes through the UPF, and there is no downlink data channel between the UPF and the UE, and the UPF caches the message.

Step 503: simultaneously with step 502, the P-CSCF sends a Policy Authorization creation Request, such as sending a Policy Authorization creation Request, to a Policy Control Function (PCF), where the Policy Authorization creation Request carries media parameters, the media parameters are generated based on media description information carried in the IMS session establishment Request, the media parameters are used to Create a mobile network connection meeting IMS session requirements, including a media type, and may also include connection address information of one end of the session connection (i.e., connection address information of the opposite end, including an IP address and a port number), a bandwidth, and the like, and the PCF sends a Policy Authorization creation Response, such as sending a Policy Authorization creation Response, to the P-CSCF.

Step 504: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, carrying QoS parameters of the IMS session, such as QoS priority information, bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 505: the same as the description of steps 202-208.

The steps 202-208 are as follows:

step 202: the IMS session establishment request reaches the user plane function UPF, the terminal UE is in an idle state, and the UPF has no channel for forwarding Data to the terminal UE, and then sends a downlink Data Notification, such as a Data Notification message, to the session management function SMF.

Step 203: the SMF sends a paging notification, such as a Namf _ Communication _ N1N2MessageTransfer Request, to the access management function AMF, carrying a paging parameter.

Step 204: the AMF sends a Paging message, such as a Paging message, to the base station.

Step 205: the base station broadcasts a Paging message.

Step 206: the terminal UE receives the broadcasted Paging message, determines that it is a Paging for itself, and then responds to the Paging message, and sends a Service Request, such as a Service Request message, to an Access Management Function (AMF) through the base station to activate a wireless air interface connection.

Step 207: the AMF sends a PDU context update Request to a session management function SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request.

Step 208: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to the user plane function UPF, and receives an N4 interface Session update Response, such as an N4Session Modification Response, which is sent by the UPF and carries UPF receiving address information.

Step 506: the SMF sends a PDU context update response to the AMF, such as sending an Nsmf _ PDU _ update smcontext Request, carrying the UPF receiving address information, and also carrying a PDU Session update Command, such as a PDU Session Modification Command message, where the PDU Session update Command may carry a rule based on the connection address information of one end of the Session connection (i.e., the connection address information of the opposite end, including the IP address and the port number), and is used for the UE to process the uplink data packet according to the rule, and also carries a QoS parameter for establishing an air interface connection.

Step 507: the AMF sends an air interface update Request to the base station, for example, sends an N2 Request, which carries parameters for establishing an air interface connection, including QoS parameters for establishing an air interface connection from the SMF and UPF receiving address information, and also carries a PDU session update command.

Step 508: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 509: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 510: the base station sends an air interface update Response to the AMF, for example, sends N2 Response, which carries the receiving address information of the base station.

Step 511: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request, which carries the receiving address information of the base station.

Step 512: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to the user plane function UPF, carrying the received address information of the base station, and receives an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 513: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 514: after step 512, the UPF has a channel for forwarding downlink data to the terminal UE, and then forwards the IMS call setup request in step 502 to the UE.

Step 515: the UE sends an IMS Ringing message to a calling subscriber, the message carries media description information (contained in an SDP Answer) of the UE, the message is transparently forwarded to a P-CSCF through a base station of a mobile network and a UPF of the mobile network, and the UE can judge whether to send an SIP 180 Ringing message carrying the SDP Answer according to whether an MO indication is received or not.

Step 516: if the IMS ringing message in step 515 carries an SDP Answer, the P-CSCF sends a Policy Authorization creation Request, such as sending a Policy Authorization Create Request, carrying media parameters of an IMS session, to the Policy control function PCF, for creating a mobile network connection that meets the IMS session requirements, including a media type, address information at both ends of the session connection, and the like, and the PCF sends a Policy Authorization creation Response, such as sending a Policy Authorization Create Response, to the P-CSCF.

517: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, to the SMF, carrying updated IMS session Policy parameters, such as opposite end connection address information, remaining QoS priority information after the media type is reduced, bandwidth, and the like, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 518: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2MessageTransfer Request, carries a PDU Session update Command, for example, a PDU Session Modification Command, the PDU Session update Command carries opposite end connection address information, and the message forwarding Request also carries updated air interface connection QoS parameters.

Step 519: the AMF sends an air interface update Request to the base station, such as sending an N2 Request, carrying the updated QoS parameters of the air interface connection from the SMF, and also carrying a PDU session update command.

Step 520: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 521: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 522: the base station sends an air interface update Response to the AMF, such as N2 Response.

Step 523: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request.

Step 524: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to a user plane function UPF, where the message carries a rule based on connection address information at one end of a Session connection (i.e., connection address information of the UE, including an IP address and a port number), and is used for the UPF to process a downlink data packet according to the rule, and receive an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 525: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 526: the user of the UE answers the IMS call, and the UE sends an IMS session answer message, such as SIP 200 OK, to the calling user, and the IMS session is closed.

In an embodiment, the embodiment mainly describes that the terminal initiates an IMS call setup through a mobile network, and specifically, as shown in fig. 8, the method includes the following steps:

step 601: the terminal UE is in an idle state, and the UE has completed a Registration process in the IMS network, for example, initiating a SIP Registration message to the IMS network, forwarding the message through a P-CSCF of the IMS network, and receiving a SIP 200 OK message forwarded through the P-CSCF from the IMS network. The P-CSCF may send an IMS indication to the UE for indicating support for fast establishment of an IMS session, for example, the IMS indication is carried in a registration response message (i.e., the above-mentioned SIP 200 OK message) or other IMS message sent to the UE.

Step 602: the UE is in an idle state, the UE intends to initiate an IMS session establishment procedure to a target user, and then sends a Service Request, for example, sends a Service Request message to activate a wireless air interface connection, to an Access Management Function (AMF) of the mobile network through a base station of the mobile network, where the message carries an IMS call establishment Request, for example, SIP INVITE message, the IMS call establishment Request may carry an MO indication for indicating that fast IMS session establishment is supported, and the UE may determine that the IMS indication in step 601 is received and then carries the IMS call establishment Request in the Service Request message.

Step 603: the AMF sends a PDU context update Request to a Session Management Function (SMF), for example, sends an Nsmf _ PDU _ update smcontext Request, which carries an IMS call setup Request received from the UE.

Step 604: the SMF forwards the IMS call setup request, which may be forwarded via the UPF, to a P-CSCF of the IMS network.

Step 605: the P-CSCF forwards the IMS call setup request to the target user via the IMS network.

Step 606: the P-CSCF sends a Policy Authorization creation Request to the Policy control function PCF, for example, sends a Policy Authorization creation Request, which carries media parameters, the media parameters are generated based on media description information carried in the IMS session creation Request, the media parameters are used to Create a mobile network connection that meets the IMS session requirements, including a media type, and may also include connection address information of one end of the session connection (i.e., connection address information of the opposite end, including an IP address and a port number), a bandwidth, and the like, and the PCF sends a Policy Authorization creation Response, for example, sends a Policy Authorization creation Response to the P-CSCF.

Step 607: the PCF sends a session management Policy update Request, such as an SM Policy Association Modification Request, carrying quality of service (QoS) parameters of the IMS session, such as QoS priority information, bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, such as an SM Policy Association Modification Response, to the PCF.

Step 608: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to a User Plane Function (UPF) of the mobile network, may carry a rule based on connection address information at one end of the Session connection (i.e., connection address information of the UE, including an IP address and a port number), and is used for the UPF to process a downlink data packet according to the rule and receive an N4 interface Session update Response, such as an N4Session Modification Response, which is sent by the UPF and carries UPF reception address information.

Step 609: the SMF sends a PDU context update Response to the AMF, such as sending an Nsmf _ pdusesion _ update smcontext Response, carrying the UPF receiving address information, carrying a PDU Session update Command, such as a PDU Session Modification Command message, and carrying a QoS parameter for establishing an air interface connection.

Step 610: the AMF sends an air interface update Request to the base station, for example, sends an N2 Request, which carries parameters for establishing an air interface connection, including QoS parameters for establishing an air interface connection from the SMF and UPF receiving address information, and also carries a PDU session update command.

Step 611: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 612: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 613: the base station sends an air interface update Response to the AMF, for example, sends N2 Response, which carries the receiving address information of the base station.

Step 614: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request, which carries the receiving address information of the base station.

Step 615: the SMF sends an N4 interface Session update Request, such as an N4Session Modification Request, to the user plane function UPF, carrying the received address information of the base station, and receives an N4 interface Session update Response, such as an N4Session Modification Response, sent by the UPF.

Step 616: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

Step 617: the P-CSCF receives an IMS call establishment response carrying media description information of a terminal of a target user from the target user, such as SIP 183 Progress, or an IMS Ringing message possibly carrying media description information of the terminal of the target user from the target user, such as SIP 180 Ringing, the P-CSCF sends the received IMS call establishment response or the received IMS Ringing message to the UE, and the message is transparently forwarded through UPF and the base station.

Step 618: if the P-CSCF receives the media description information from the terminal of the target user, the P-CSCF sends a Policy Authorization creation Request to the Policy control function PCF, such as sending a Policy Authorization creation Request, which carries the media parameters of the IMS session, and is used for creating a mobile network connection meeting the requirements of the IMS session, including the media type, address information of two ends of the session connection, and the like, and the PCF sends a Policy Authorization creation Response to the P-CSCF, such as sending a Policy Authorization creation Response.

Step 619: the PCF finds that the Policy information is updated, for example, the connection address information of the opposite end is added, or the media type is reduced, etc., the PCF sends a session management Policy update Request, for example, the SM Policy Association Modification Request is sent, which carries updated IMS session Policy parameters, for example, the connection address information of the opposite end, the remaining QoS priority information after the media type is reduced, the bandwidth, etc., to the SMF, and the SMF sends a session management Policy update Response, for example, the SM Policy Association Modification Response is sent to the PCF.

Step 620: the SMF sends a message forwarding Request to the AMF, for example, sends a Namf _ Communication _ N1N2MessageTransfer Request, carries a PDU Session update Command, for example, a PDU Session Modification Command, the PDU Session update Command carries opposite end connection address information, and the message forwarding Request also carries updated air interface connection QoS parameters.

Step 621: the AMF sends an air interface update Request to the base station, such as sending an N2 Request, carrying the updated QoS parameters of the air interface connection from the SMF, and also carrying a PDU session update command.

Step 622: the base station sends an air interface configuration Request, such as an RRC Connection Reconfiguration Request, to the UE, where the air interface configuration Request carries a PDU session update command.

Step 623: the UE sends an air interface configuration Response, such as an RRC Connection Reconfiguration Response, to the base station.

Step 624: the base station sends an air interface update Response to the AMF, such as N2 Response.

Step 625: the AMF sends a PDU context update Request to the SMF, such as an Nsmf _ PDUSESS _ UpdateSMContext Request.

Step 626: the SMF sends a PDU context update Response to the AMF, such as an Nsmf _ PDUSESSion _ UpdateSMContext Response.

The following steps 627-629 exist only if a response is set up for the IMS call at step 617.

Step 627: the UE sends an IMS session resource reservation completion message to the target user through the P-CSCF, for example, the SIP PRACK message is sent, the message is transparently forwarded through the base station and the UPF, and the P-CSCF forwards the message to the target user.

Step 628: the UE receives an IMS session resource reservation confirm message, such as a SIP 200 OK message, for the target user.

Step 629: the UE receives an IMS Ringing message of the target user, such as an SIP 180 Ringing message, and plays a reminding sound to prompt the user that the IMS call connection is established and the target user rings.

Step 630: the target user answers the IMS call, the UE receives an IMS session answering message from the target user, such as SIP 200 OK, and the IMS session is connected.

If step 617 is an IMS ringing message and does not carry media description information, the media description information of the terminal of the target user is received only in step 630, that is, steps 618 to 626 occur after step 630.

The terminal in the embodiment of the invention can be realized as follows:

receiving an IMS session establishment request from a calling user, and sending an IMS ringing message carrying media description information to the calling user; or the like, or, alternatively,

and sending an IMS session establishment request carrying an MO indication to an IMS network, wherein the MO indication is used for indicating that the fast IMS session establishment is supported.

Further, the IMS session establishment request carries an MO indication, where the MO indication is used to indicate that fast IMS session establishment is supported.

Further, if the IMS session establishment request carries the MO indication, an IMS ringing message carrying media description information is sent.

Further, an IMS indication of an IMS network is received, the indication indicating that the IMS network supports fast IMS session establishment.

And further, if the IMS indication is judged to be received, sending an IMS session establishment request carrying the MO indication.

Further, if the IMS indication is received, the IMS ringing message is sent.

Further, the IMS session setup request is carried over non-access stratum (NAS) signaling.

The first network function (e.g., P-CSCF) in the embodiments of the present invention may be implemented as follows:

receiving an IMS call establishment request from a terminal UE or sending the IMS call establishment request to the terminal;

sending media parameters to a second network function (PCF) in the mobile network, the media parameters being obtained by the content of the IMS call setup request.

Further, an IMS ringing message is received from the terminal UE, and a user plane management event notification is received from a third network function (SMF) in the mobile network, forwarding the IMS ringing message.

Further, an IMS indication is sent to the terminal UE, and the IMS indication is used for indicating that the fast IMS session establishment is supported.

Referring to fig. 9, fig. 9 is a structural diagram of a terminal according to an embodiment of the present invention, where the terminal is a first terminal, and as shown in fig. 9, the terminal 900 includes:

a sending module 901, configured to send an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment method supported by the first terminal;

Optionally, the terminal sends a non-access stratum NAS request, where the NAS request carries the IMS call message.

Optionally, before sending the IMS call message, as shown in fig. 10, the terminal 900 further includes:

a receiving module 902, configured to receive second indication information from a network, where the second indication information is used to indicate an IMS session establishment method supported by the network.

Optionally, the terminal determines that the IMS call message carries the first indication information according to the second indication information.

The terminal provided by the embodiment of the present invention can implement each process implemented by the terminal in the method embodiment of fig. 2, and for avoiding repetition, details are not described here, and the IMS call performance in the communication system can be improved.

Referring to fig. 11, fig. 11 is a structural diagram of a terminal according to an embodiment of the present invention, where the terminal is a second terminal, and as shown in fig. 11, a terminal 1100 includes:

a receiving module 1101, configured to receive an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment method supported by a first terminal that initiates the IMS call message;

a sending module 1102, configured to send an IMS ringing message, where the IMS ringing message carries media information;

Optionally, the receiving module 1001 is further configured to receive second indication information from a network, where the second indication information is used to indicate an IMS session establishment method supported by the network.

The network function provided by the embodiment of the present invention can implement each process implemented by the second terminal in the method embodiment of fig. 3, which is not described herein again to avoid repetition, and can improve IMS call performance in the communication system.

Referring to fig. 12, fig. 12 is a structural diagram of a network function according to an embodiment of the present invention, where the network function is a first network function, and as shown in fig. 12, the network function 1200 includes:

a transmission module 1201, configured to receive an IMS call message from a first terminal, or send the IMS call message to a second terminal;

a sending module 1202, configured to send a policy authorization creation request to a policy control function, where the policy authorization creation request carries media parameters, and the media parameters are obtained through the IMS call message.

Optionally, as shown in fig. 13, the network function 1200 further includes:

a receiving module 1203, configured to receive an IMS ringing message from the second terminal, where the IMS ringing message carries media information.

Optionally, the sending module transmission module 1201 is further configured to receive a resource reservation completion notification message sent by the session management function, and forward the IMS ringing message.

Optionally, the sending module 1102 is further configured to send second indication information to the first terminal or the second terminal, where the second indication information is used to indicate an IMS session establishment manner supported by the first network function.

The network function provided in the embodiment of the present invention can implement each process of implementing the first network function in the method embodiment of fig. 4, which is not described herein again to avoid repetition, and can improve IMS call performance in the communication system.

Figure 14 is a schematic diagram of the hardware architecture of a terminal implementing various embodiments of the invention,

the terminal 1400 includes but is not limited to: radio frequency unit 1401, network module 1402, audio output unit 1403, input unit 1404, sensor 1405, display unit 1406, user input unit 1407, interface unit 1408, memory 1409, processor 1410, and power supply 1411. Those skilled in the art will appreciate that the terminal configuration shown in fig. 14 is not intended to be limiting, and that the terminal may include more or fewer components than shown, or some components may be combined, or a different arrangement of components. In the embodiment of the present invention, the terminal includes, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted terminal, a robot, a wearable device, a pedometer, and the like.

In an embodiment where the terminal is a first terminal:

a radio frequency unit 1401, configured to send an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment method supported by the first terminal;

Optionally, before sending the IMS call message, the radio frequency unit 1401 is further configured to:

In an embodiment where the terminal is a second terminal:

a radio frequency unit 1401, configured to receive an IMS call message, where the IMS call message carries first indication information, and the first indication information is used to indicate an IMS session establishment mode supported by a first terminal that initiates the IMS call message;

the radio frequency unit 1401 is further configured to send an IMS ringing message, where the IMS ringing message carries media information;

The terminal can improve the IMS calling performance in the communication system.

It should be understood that, in the embodiment of the present invention, the radio frequency unit 1401 may be configured to receive and transmit signals during a message transmission or call process, and specifically, receive downlink data from a base station and then process the received downlink data to the processor 1410; in addition, the uplink data is transmitted to the base station. In general, radio unit 1401 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. The radio unit 1401 may also communicate with a network and other devices via a wireless communication system.

The terminal provides the user with wireless broadband internet access through the network module 1402, such as helping the user send and receive e-mails, browse webpages, access streaming media, and the like.

The audio output unit 1403 can convert audio data received by the radio frequency unit 1401 or the network module 1402 or stored in the memory 1409 into an audio signal and output as sound. Also, the audio output unit 1403 may also provide audio output related to a specific function performed by the terminal 1400 (e.g., a call signal reception sound, a message reception sound, etc.). The audio output unit 1403 includes a speaker, a buzzer, a receiver, and the like.

The input unit 1404 is for receiving an audio or video signal. The input Unit 1404 may include a Graphics Processing Unit (GPU) 14041 and a microphone 14042, the Graphics processor 14041 Processing 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 processed image frames may be displayed on the display unit 1406. The image frames processed by the graphics processor 14041 may be stored in the memory 1409 (or other storage medium) or transmitted via the radio unit 1401 or the network module 1402. The microphone 14042 may receive sound and may be capable of processing such sound into audio data. The processed audio data may be converted into a format output transmittable to a mobile communication base station via the radio frequency unit 1401 in case of a phone call mode.

Terminal 1400 also includes at least one sensor 1405, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor includes an ambient light sensor that adjusts the brightness of the display panel 14061 according to the brightness of ambient light, and a proximity sensor that turns off the display panel 14061 and/or the backlight when the terminal 1400 moves to the ear. As one of the motion sensors, the accelerometer sensor can detect the magnitude of acceleration in each direction (generally three axes), detect the magnitude and direction of gravity when stationary, and can be used to identify the terminal posture (such as horizontal and vertical screen switching, related games, magnetometer posture calibration), vibration identification related functions (such as pedometer, tapping), and the like; the sensors 1405 may also include fingerprint sensors, pressure sensors, iris sensors, molecular sensors, gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc., which are not described in detail herein.

The display unit 1406 is used to display information input by the user or information provided to the user. The Display unit 1406 may include a Display panel 14061, and the Display panel 14061 may be configured in the form of a Liquid Crystal Display (LCD), an Organic Light-Emitting Diode (OLED), or the like.

The user input unit 1407 may be used to receive input numeric or character information and generate key signal inputs related to user settings and function control of the terminal. Specifically, the user input unit 1407 includes a touch panel 14071 and other input devices 14072. The touch panel 14071, also referred to as a touch screen, may collect touch operations by a user (e.g., operations by a user on or near the touch panel 14071 using a finger, a stylus, or any other suitable object or attachment). The touch panel 14071 may include two parts of a touch detection device and a touch controller. The touch detection device detects the touch direction of a user, detects a signal brought by touch operation and transmits the signal to the touch controller; the touch controller receives touch information from the touch sensing device, converts the touch information into touch point coordinates, sends the touch point coordinates to the processor 1410, receives a command from the processor 1410, and executes the command. In addition, the touch panel 14071 can be implemented by various types such as resistive, capacitive, infrared, and surface acoustic wave. In addition to the touch panel 14071, the user input unit 1407 may include other input devices 14072. In particular, the other input devices 14072 may include, but are not limited to, a physical keyboard, function keys (such as volume control keys, switch keys, etc.), a trackball, a mouse, and a joystick, which are not described herein.

Further, the touch panel 14071 may be overlaid on the display panel 14061, and when the touch panel 14071 detects a touch operation on or near the touch panel 14071, the touch operation is transmitted to the processor 1410 to determine the type of the touch event, and then the processor 1410 provides a corresponding visual output on the display panel 14061 according to the type of the touch event. Although in fig. 14, the touch panel 14071 and the display panel 14061 are two independent components to implement the input and output functions of the terminal, in some embodiments, the touch panel 14071 and the display panel 14061 may be integrated to implement the input and output functions of the terminal, which is not limited herein.

The interface unit 1408 is an interface to which an external device is connected with the terminal 1400. For example, the external device may include a wired or wireless headset port, an external power supply (or battery charger) port, a wired or wireless data port, a memory card port, a port for connecting a device having an identification module, an audio input/output (I/O) port, a video I/O port, an earphone port, and the like. Interface unit 1408 may be used to receive input from external devices (e.g., data information, power, etc.) and transmit the received input to one or more elements within terminal 1400 or may be used to transmit data between terminal 1400 and external devices.

The memory 1409 may be used to store software programs as well as various data. The memory 1409 may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application program required for at least one function (such as a sound playing function, an image playing function, etc.), and the like; the storage data area may store data (such as audio data, a phonebook, etc.) created according to the use of the cellular phone, and the like. In addition, the memory 1409 can include high speed random access memory and can also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device.

The processor 1410 is a control center of the terminal, connects various parts of the entire terminal using various interfaces and lines, performs various functions of the terminal and processes data by operating or executing software programs and/or modules stored in the memory 1409 and calling data stored in the memory 1409, thereby performing overall monitoring of the terminal. Processor 1410 may include one or more processing units; preferably, the processor 1410 may integrate an application processor, which mainly handles operating systems, user interfaces, application programs, etc., and a modem processor, which mainly handles wireless communications. It will be appreciated that the modem processor described above may not be integrated into processor 1410.

The terminal 1400 may further include a power source 1411 (e.g., a battery) for supplying power to various components, and preferably, the power source 1411 may be logically connected to the processor 1410 via a power management system, so as to implement functions of managing charging, discharging, and power consumption via the power management system.

In addition, terminal 1400 includes some functional modules that are not shown, and are not described herein.

Preferably, an embodiment of the present invention further provides a terminal, including a processor 1410, a memory 1409, and a computer program stored in the memory 1409 and capable of running on the processor 1410, where the computer program, when executed by the processor 1410, implements each process of the above-mentioned IMS call method embodiment on the first terminal side or the second terminal side, and can achieve the same technical effect, and in order to avoid repetition, it is not described herein again.

Referring to fig. 15, fig. 15 is a structural diagram of another network function according to an embodiment of the present invention, and as shown in fig. 15, the network function 1500 includes: a processor 1501, a transceiver 1502, a memory 1503, and a bus interface, wherein:

a transceiver 1502 for receiving an IMS call message from a first terminal or transmitting an IMS call message to a second terminal;

the transceiver 1502 is further configured to send a policy authorization creation request to a policy control function, where the policy authorization creation request carries media parameters, where the media parameters are obtained through the IMS call message.

Optionally, after sending the IMS call message to the second terminal, the transceiver 1502 is further configured to:

Optionally, after receiving the IMS ringing message from the second terminal, the transceiver 1502 is further configured to:

Optionally, before receiving the IMS call message from the first terminal or before sending the IMS call message to the second terminal, the transceiver 1502 is further configured to:

The network functions described above may improve IMS call performance in a communication system.

Wherein the transceiver 1502 is configured to receive and transmit data under the control of the processor 1501, the transceiver 1502 includes at least two antenna ports.

In fig. 15, the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 1501, and various circuits, represented by memory 1503, linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1502 may be a plurality of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium. The user interface 1504 may also be an interface capable of interfacing with a desired device for different user devices, including but not limited to a keypad, display, speaker, microphone, joystick, etc.

The processor 1501 is responsible for managing a bus architecture and general processing, and the memory 1503 may store data used by the processor 1501 in performing operations.

Preferably, an embodiment of the present invention further provides a network device, including a processor 1501, a memory 1503, and a computer program stored in the memory 1503 and operable on the processor 1501, where the computer program, when executed by the processor 1501, implements each process of the IMS call method embodiment on the first network function side, and can achieve the same technical effect, and in order to avoid repetition, the detailed description is omitted here.

An embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the IMS call method on the first terminal side provided in the embodiment of the present invention is implemented, or when the computer program is executed by the processor, the IMS call method on the second terminal side provided in the embodiment of the present invention is implemented, or when the computer program is executed by the processor, the IMS call method on the first network function side provided in the embodiment of the present invention is implemented, and the same technical effect can be achieved, and in order to avoid repetition, details are not described here again. The computer-readable storage medium may be a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk.

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 an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal (such as a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An internet protocol multimedia subsystem (IMS) calling method is applied to a first terminal and is characterized by comprising the following steps:

2. The method of claim 1, wherein the terminal sends a non-access stratum (NAS) request, the NAS request carrying the IMS call message.

3. The method of claim 1, wherein prior to said sending the IMS call message, the method further comprises:

4. The method of claim 3, wherein the terminal determines to carry the first indication information in the IMS call message according to the second indication information.

5. An IMS call method applied to a second terminal, comprising:

6. The method of claim 5, wherein prior to said sending the IMS call message, the method further comprises:

7. The method of claim 6, wherein the terminal determines to carry the media information in the IMS ringing message according to the second indication information.

8. An IMS call method applied to a first network function, comprising:

and sending a policy authorization establishing request to a policy control function, wherein the policy authorization establishing request carries media parameters, and the media parameters are obtained through the IMS call message.

9. The method of claim 8, wherein after sending the IMS call message to the second terminal, the method further comprises:

10. The method of claim 9, wherein after receiving the IMS ringing message from the second terminal, the method further comprises:

11. The method of claim 8, wherein prior to receiving the IMS call message from the first terminal or sending the IMS call message to the second terminal, the method further comprises:

12. A terminal, the terminal being a first terminal, comprising:

13. A terminal, the terminal being a second terminal, comprising:

14. A network function, the network function being a first network function, comprising:

15. A terminal, the terminal being a first terminal, comprising: memory, processor and program stored on the memory and executable on the processor, which when executed by the processor implements the steps in the IMS call method of any of claims 1 to 4.

16. A terminal, the terminal being a second terminal, comprising: memory, processor and program stored on the memory and executable on the processor, which when executed by the processor implements the steps in the IMS call method of any of claims 5 to 7.

17. A network function, the network function being a first network function, comprising: memory, processor and program stored on the memory and executable on the processor, which when executed by the processor implements the steps in the IMS call method according to any of claims 8 to 11.

18. A computer readable storage medium, characterized in that a computer program is stored thereon, which computer program, when being executed by a processor, realizes the steps in the IMS call method as set forth in any one of claims 1 to 4, or which computer program, when being executed by a processor, realizes the steps in the IMS call method as set forth in any one of claims 5 to 7, or which computer program, when being executed by a processor, realizes the steps in the IMS call method as set forth in any one of claims 8 to 11.