Communication method, apparatus, device, system, chip and storage medium

Abstract

The present disclosure provides a communication method, device, equipment, system, chip and storage medium, wherein the method comprises: a first network element judges whether a first terminal and a second terminal are connected to a same satellite when the first terminal requests to have an IMS call with the second terminal, wherein the satellite comprises a first UPF, and the first network element sends an indication message to a second network element in a case that the first terminal and the second terminal are determined to be connected to the same satellite, wherein the indication message is used to indicate that the first terminal and the second terminal meet the condition of having an IMS call through the satellite. Thus, the second network element can conveniently know that the first terminal and the second terminal meet the condition of having an IMS call through the satellite through the indication information, and the first terminal and the second terminal can directly have an IMS call through the satellite, which reduces the transmission delay of the first terminal and the second terminal when having an IMS call through a satellite communication network, and improves the call efficiency between the two.

Description

Technical Field

[0001] This disclosure relates to the field of satellite communication technology, and in particular to a communication method, apparatus, device, system, chip, and storage medium. Background Technology

[0002] Currently, with the introduction of Internet Protocol Multimedia Subsystem (IMS) calls into satellite communication networks, the typical transmission path for media plane data during IMS calls between the first and second terminals is: first terminal → satellite → User Plane Function (UPF) → Calling Session Border Controller (SBC) → Called SBC → UPF → satellite → second terminal. However, this transmission path is relatively long, resulting in low call efficiency between the first and second terminals when conducting IMS calls via satellite communication networks. Summary of the Invention

[0003] This disclosure provides a communication method, apparatus, device, system, chip, and storage medium to solve the technical problem of low call efficiency when a first terminal and a second terminal make IMS calls through a satellite communication network.

[0004] In a first aspect, embodiments of this disclosure provide a communication method applied in a first network element. The method includes: receiving a first session invitation request from a first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with a second terminal; determining whether the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first User Plane Function (UPF); and, if it is determined that the first terminal and the second terminal are connected to the same satellite, sending an indication message to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting an IMS call via the satellite.

[0005] Secondly, embodiments of this disclosure provide a communication method applied in a second network element. The method includes: receiving an indication message sent by a first network element, wherein the indication message is used to indicate that a first terminal and a second terminal meet the conditions for conducting IMS communication via satellite, wherein the satellite includes a first user plane function (UPF); and sending the indication message to a third network element.

[0006] Thirdly, embodiments of this disclosure provide a communication method applied in a third network element. The method includes: receiving an indication message sent by a second network element, wherein the indication message is used to indicate that a first terminal and a second terminal meet the conditions for conducting IMS calls via satellite, wherein the satellite includes a first user plane function (UPF); and sending a notification message to the first UPF, wherein the notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS calls via the first UPF.

[0007] Fourthly, embodiments of this disclosure provide a communication method applied in a first terminal. The method includes: sending a first session invitation request to a first network element, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with a second terminal; receiving a response message sent by the first network element in response to the first session invitation request, wherein the response message carries address information of a first User Plane Function (UPF) on a satellite, and the response message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite; and performing an IMS call based on the address information of the first UPF.

[0008] Fifthly, embodiments of this disclosure provide a communication method applied in a second terminal. The method includes: receiving a second session invitation request sent by a first network element, wherein the second session invitation request is a request from a first terminal to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal; sending a response message to the first network element in response to the second session invitation request; receiving a session update message sent by the first network element, wherein the session update message includes: address information of a first User Plane Function (UPF) on a satellite, wherein both the first terminal and the second terminal are connected to the satellite; and conducting an IMS call based on the address information of the first UPF.

[0009] In a sixth aspect, embodiments of this disclosure provide a communication method applied in a first user plane function (UPF) of a satellite. The method includes: receiving a notification message sent by a third network element, wherein the notification message is used to notify a first terminal and a second terminal of the first UPF that they will conduct an IMS call through the first UPF; receiving media plane data of the IMS call from the first terminal and forwarding the media plane data to the second terminal, or receiving media plane data of the IMS call from the second terminal and forwarding the media plane data to the first terminal.

[0010] In a seventh aspect, embodiments of this disclosure provide a communication device applied in a first network element. The device includes: a receiving module, configured to receive a first session invitation request from a first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with a second terminal; a determining module, configured to determine whether the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first User Plane Function (UPF); and a sending module, configured to send an indication message to the second network element when it is determined that the first terminal and the second terminal are connected to the same satellite, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting an IMS call via the satellite.

[0011] Eighthly, this disclosure provides a communication device applied in a second network element. The device includes: a receiving module for receiving an indication message sent by a first network element, wherein the indication message indicates that a first terminal and a second terminal meet the conditions for conducting IMS communication via satellite, wherein the satellite includes a first user plane function (UPF); and a sending module for sending the indication message to a third network element.

[0012] Ninthly, embodiments of this disclosure provide a communication device applied in a third network element. The device includes: receiving an indication message sent by a second network element, wherein the indication message is used to indicate that a first terminal and a second terminal meet the conditions for conducting IMS communication via satellite, wherein the satellite includes a first user plane function (UPF); and sending a notification message to the first UPF, wherein the notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS communication via the first UPF.

[0013] Tenthly, embodiments of this disclosure provide a communication device applied in a first terminal. The device includes: a sending module, configured to send a first session invitation request to a first network element, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with a second terminal; a receiving module, configured to receive a response message sent by the first network element in response to the first session invitation request, wherein the response message carries address information of a first User Plane Function (UPF) on a satellite, and the response message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite; and an IMS call module, configured to perform an IMS call based on the address information of the first UPF.

[0014] Eleventhly, this disclosure provides a communication device applied in a second terminal. The device includes: a first receiving module for receiving a second session invitation request sent by a first network element, wherein the second session invitation request is a request from the first terminal to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal; a first sending module for sending a response message to the first network element in response to the second session invitation request; a second receiving module for receiving a session update message sent by the first network element, wherein the session update message carries address information of a first User Plane Function (UPF) on a satellite, wherein the session update message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite; and an IMS call module for conducting an IMS call based on the address information of the first UPF.

[0015] In a twelfth aspect, embodiments of this disclosure provide a communication device applied in a first user plane function (UPF) of a satellite. The device includes: a first receiving module, configured to receive a notification message sent by a third network element, wherein the notification message is used to notify a first terminal and a second terminal of the first UPF that they will conduct an IMS call through the first UPF; and a second receiving module, configured to receive media plane data of the IMS call from the first terminal and forward the media plane data to the second terminal, or to receive media plane data of the IMS call from the second terminal and forward the media plane data to the first terminal.

[0016] In a thirteenth aspect, embodiments of this disclosure provide a communication device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the communication method disclosed in embodiments of this disclosure.

[0017] In a fourteenth aspect, embodiments of this disclosure provide a communication system, the communication system comprising: a first terminal, a second terminal, a first user plane function (UPF) on a satellite, a first network element, a second network element, and a third network element, wherein: the first network element is used to implement the method described in the first aspect of embodiments of this disclosure; the second network element is used to implement the method described in the second aspect of embodiments of this disclosure; the third network element is used to implement the method described in the third aspect of embodiments of this disclosure; the first terminal is used to implement the method described in the fourth aspect of embodiments of this disclosure; the second terminal is used to implement the method described in the fifth aspect of embodiments of this disclosure; and the first UPF is used to implement the method described in the sixth aspect of embodiments of this disclosure.

[0018] In a fifteenth aspect, embodiments of this disclosure provide a chip including one or more interface circuits and one or more processors; the interface circuits are configured to receive signals from a memory of a communication device and send the received signals to the processors, the received signals including computer instructions stored in the memory, and when the processor executes the computer instructions, the communication device implements the communication method disclosed in embodiments of this disclosure.

[0019] In a sixteenth aspect, embodiments of the present disclosure provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the communication method disclosed in embodiments of the present disclosure.

[0020] In a seventeenth aspect, embodiments of this disclosure provide a computer program product that, when executed by an instruction processor in the computer program product, implements the communication method disclosed in embodiments of this disclosure.

[0021] The technical solutions provided by the embodiments of this disclosure have at least the following beneficial effects:

[0022] When the first terminal requests an IMS call with the second terminal, it determines whether the first and second terminals are connected to the same satellite. If it is determined that the first and second terminals are connected to the same satellite, an indication message is sent to the second network element. This indication message indicates that the first and second terminals meet the conditions for IMS calling via satellite. Therefore, the second network element can easily determine that the first and second terminals meet the conditions for IMS calling via satellite through the indication information, enabling the first and second terminals to directly conduct IMS calls via satellite. This reduces the transmission latency when the first and second terminals conduct IMS calls through the satellite communication network and improves the call efficiency between them.

[0023] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0024] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1 This is a schematic diagram of the architecture of a satellite communication system provided in an embodiment of the present disclosure;

[0026] Figure 2 This is a flowchart illustrating a communication method provided in an embodiment of the present disclosure;

[0027] Figure 3 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0028] Figure 4 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0029] Figure 5 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0030] Figure 6 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0031] Figure 7 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0032] Figure 8 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0033] Figure 9 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0034] Figure 10 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0035] Figure 11 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0036] Figure 12 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0037] Figure 13 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0038] Figure 14 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0039] Figure 15 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0040] Figure 16 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure;

[0041] Figure 17 This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0042] Figure 18 This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0043] Figure 19This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0044] Figure 20 This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0045] Figure 21 This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0046] Figure 22 This is a schematic diagram of the structure of a communication device provided in an embodiment of the present disclosure;

[0047] Figure 23 This is a schematic diagram of the structure of a communication system provided in an embodiment of the present disclosure;

[0048] Figure 24 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the PCF network element, the SMF network element, and the first UPF on the satellite. Figure 1 ;

[0049] Figure 25 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the PCF network element, the SMF network element, and the first UPF on the satellite. Figure 2 ;

[0050] Figure 26 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the SMF network element, the PCF network element, and the first UPF on the satellite. Figure 3 ;

[0051] Figure 27 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the SMF network element, the PCF network element, and the first UPF on the satellite. Figure 4 ;

[0052] Figure 28 This is a block diagram illustrating a communication device for implementing a communication method according to an exemplary embodiment;

[0053] Figure 29 This is a schematic diagram of the structure of a chip according to an exemplary embodiment. Detailed Implementation

[0054] Embodiments of this disclosure are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this disclosure, and should not be construed as limiting this disclosure.

[0055] To better understand the communication method disclosed in this embodiment, the satellite communication system to which this embodiment applies is first described below.

[0056] Please see Figure 1 , Figure 1 This is a schematic diagram of the architecture of a satellite communication system provided in an embodiment of this disclosure. The satellite communication system may include a satellite 101, a terminal 102, and a gateway station 103.

[0057] In this disclosure, satellite 101 is an entity used for transmitting or receiving signals. The embodiments of this disclosure do not limit the specific technologies or equipment used in the satellite.

[0058] In this disclosure, terminal 102 refers to a processing device within the satellite coverage beam range for communicating with a satellite. For example, the terminal can be a car with satellite communication capabilities, a smart car, a mobile phone, a wearable device, a tablet computer, etc. This disclosure does not limit the specific technology or device form used in the terminal.

[0059] It should be noted that, Figure 1 The example uses two terminal devices 102.

[0060] In one embodiment of this disclosure, gateway station 103 is connected to satellite 101.

[0061] In this embodiment, the gateway station 103 is a ground-based node in a satellite communication system used for transmitting and receiving data. This embodiment does not limit the specific technology or equipment form employed by the gateway station.

[0062] It is understood that the satellite communication system described in this disclosure is for the purpose of more clearly illustrating the technical solutions of this disclosure, and does not constitute a limitation on the technical solutions provided in this disclosure. As those skilled in the art will know, with the evolution of system architecture and the emergence of new business scenarios, the technical solutions provided in this disclosure are also applicable to similar technical problems.

[0063] In the aforementioned satellite system, after introducing Internet Protocol Multimedia Subsystem (IMS) calls into the satellite communication network, Figure 1 When the two terminals shown are making an IMS call, the transmission path of the media plane data is the first terminal ( Figure 1One of the two terminals shown) → Satellite → User Plane Function (UPF) → Calling Session Border Controller (SBC) → Called SBC → Ground UPF → Satellite → Second Terminal ( Figure 1 (The other terminal shown is one of the two terminals). However, the transmission path for IMS calls between the two terminals is relatively long, resulting in low call efficiency when making IMS calls via satellite communication networks. Therefore, improving the call efficiency of IMS calls between the two terminals via satellite communication networks is an urgent problem to be solved.

[0064] This disclosure provides a communication method, apparatus, device, system, chip, and storage medium that enables two terminals to make IMS calls directly via satellite, reducing transmission latency when the two terminals make IMS calls through a satellite communication network and improving the call efficiency between them.

[0065] The following description, with reference to the accompanying drawings, describes communication methods, apparatus, devices, systems, chips, and storage media according to embodiments of the present disclosure.

[0066] Figure 2 This is a schematic flowchart illustrating a communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. This communication device can be implemented using software and / or hardware. The communication device can be located in or configured within a first network element.

[0067] It should be noted that the first network element in this example can be a P-CSCF network element in the 5G core network or other network elements that can use the communication methods provided in the embodiments of this disclosure.

[0068] In this embodiment, the communication method is executed by the first network element as an example for illustrative description.

[0069] like Figure 2 As shown, the communication method may include the following steps:

[0070] Step 201: Receive the first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0071] The first terminal refers to the terminal device that initiates the IMS call request.

[0072] In some examples, the first terminal may also be referred to as the calling terminal or the Mobile Originating User Equipment (MOUE).

[0073] The second terminal is the terminal device that receives IMS call requests.

[0074] In some examples, the second terminal may also be referred to as the called terminal or the Mobile Terminating User Equipment (MTUE).

[0075] The first session invitation request carries all or part of the following information: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP). In other words, the first session invitation request may include at least one or more of the following information: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0076] The SDP contains the media address of the first terminal and the media types and encoding / decoding information supported by the first terminal.

[0077] SDP is primarily used for media negotiation before the session begins.

[0078] The media address is the address used to send and receive media streams.

[0079] In one example, the first session invitation request can be a Session Initiation Protocol (SIP) INVITE message.

[0080] Step 202: Determine whether the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first user plane function (UPF).

[0081] It is understandable that the methods for determining whether the first terminal and the second terminal are connected to the same satellite differ in different application scenarios. Examples are illustrated below:

[0082] As one possible implementation, it can be determined whether the first terminal and the second terminal are connected to the same satellite based on the satellite identifier of the satellite to which the first terminal is connected and the satellite identifier of the satellite to which the second terminal is connected. If the satellite identifiers of the satellites to which the first terminal and the second terminal are connected are the same, then it is determined that the first terminal and the second terminal are connected to the same satellite.

[0083] As another possible implementation, it can be determined whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal.

[0084] The location information of the first terminal refers to the relevant data that determines the current geographical location of the first terminal.

[0085] In this example, the location information of the first terminal may include at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, and the access network type information corresponding to the first terminal.

[0086] In one embodiment, the base station connected to the first terminal may be located on a satellite.

[0087] The location information of the second terminal refers to the relevant data that determines the current geographical location of the second terminal.

[0088] In this example, the location information of the second terminal may include at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, and the access network type information corresponding to the second terminal.

[0089] In one embodiment, the base station connected to the second terminal can be located on a satellite.

[0090] As an example, if the location information of the first terminal includes the cell identifier information of the cell where the first terminal is located, and the location information of the second terminal includes the cell identifier information of the cell where the second terminal is located, it can be determined whether the first terminal and the second terminal are connected to the same satellite based on whether the two cell identifier information are consistent.

[0091] Specifically, if the cell identification information of the two terminals is consistent, it is determined that the first terminal and the second terminal are connected to the same satellite. Conversely, if the cell identification information of the two terminals is inconsistent, it is determined that the first terminal and the second terminal are connected to different satellites.

[0092] As another example, if the location information of the first terminal includes the base station identifier of the base station to which the first terminal is connected, and the location information of the second terminal includes the base station identifier of the base station to which the second terminal is connected, it can be determined whether the first terminal and the second terminal are connected to the same satellite based on whether the two base station identifiers are consistent.

[0093] Specifically, if the two base station identifiers are identical, it is determined that the first terminal and the second terminal are connected to the same satellite. Conversely, if the two base station identifiers are inconsistent, it is determined that the first terminal and the second terminal are connected to different satellites.

[0094] As another example, if the location information of the first terminal includes the access network type information corresponding to the first terminal, and the location information of the second terminal includes the access network type information corresponding to the second terminal, it can be determined whether the first terminal and the second terminal are connected to the same satellite based on whether the two access network type information are consistent.

[0095] Specifically, if the two access network type information are consistent, it is determined that the first terminal and the second terminal are connected to the same satellite. Conversely, if the two access network type information are inconsistent, it is determined that the first terminal and the second terminal are connected to different satellites.

[0096] Step 203: If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0097] As an example, if the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, it means that the first terminal and the second terminal devices can directly conduct IMS calls via satellite. That is, media plane data during an IMS call between the first terminal and the second terminal can be directly forwarded via satellite.

[0098] As an example, the instruction message is used to indicate that the first terminal and the second terminal meet the conditions for conducting an IMS call via the first UPF on the satellite.

[0099] In one example, media plane data during an IMS call between a first terminal and a second terminal can be forwarded via a first UPF on a satellite.

[0100] It is understood that, in cases where the first terminal and the second terminal are connected to different satellites, the first terminal and the second terminal cannot forward media plane data during an IMS call via satellite.

[0101] In order to enable the second network element to know the pairing relationship between the first terminal and the second terminal, so as to facilitate subsequent processing based on the pairing information, in one embodiment, the above-mentioned indication information may also include the identification information of the first terminal and the second terminal.

[0102] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0103] As an example, the second network element in this example can forward the indication information to the third network element. Correspondingly, if the indication information includes the identification information of the first terminal and the second terminal, the third network element can obtain the identification information of the first terminal and the second terminal based on the indication information and send a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF, and the notification message can carry the identification information of the first terminal and the second terminal.

[0104] It can be understood that after the first UPF learns the identification information of the first terminal and the second terminal, it can bind the identification information of the first terminal and the second terminal to obtain the binding relationship between the two, and forward the media plane data of the IMS call between the first terminal and the second terminal based on the binding relationship.

[0105] The communication method provided in this embodiment involves a first network element determining whether the first and second terminals are connected to the same satellite when the first terminal requests an IMS call with the second terminal. The satellite includes a first UPF. If it is determined that the first and second terminals are connected to the same satellite, the first network element sends an indication message to the second network element. This indication message indicates that the first and second terminals meet the conditions for conducting an IMS call via satellite. This allows the second network element to easily determine that the first and second terminals meet the conditions for conducting an IMS call via satellite through the indication information, enabling the first and second terminals to directly conduct an IMS call via satellite. This reduces the transmission latency when the first and second terminals conduct an IMS call through a satellite communication network and improves the call efficiency between them.

[0106] It should be noted that, in the embodiments disclosed herein, some or all of the steps and their optional implementations may be arbitrarily combined with some or all of the steps in other embodiments, or may be arbitrarily combined with the optional implementations in other embodiments.

[0107] In the embodiments disclosed herein, each step and its optional implementation can also be carried out independently.

[0108] Figure 3 This is a flowchart illustrating another communication method provided in an embodiment of the present disclosure.

[0109] like Figure 3 As shown, the communication method may include the following steps:

[0110] Step 301: Receive a first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal, and the session invitation request includes the location information of the first terminal.

[0111] It should be noted that, in addition to carrying the location information of the first terminal, the first session invitation request may also include the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0112] In this example, the location information of the first terminal may include at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, and the access network type information corresponding to the first terminal.

[0113] As an example, when the first terminal detects that it is connected to a satellite, it can carry the location information of the first terminal in the first session invitation request.

[0114] The satellite to which the first terminal is connected may include a base station.

[0115] As an example, when the first terminal detects that it is connected to a base station on a satellite, it can carry the location information of the first terminal in the first session invitation request.

[0116] Step 302: Send a second session invitation request to the second terminal.

[0117] In this example, the first session invitation request and the second session invitation request can be the same or different.

[0118] As an example, a second session invitation request can also be a SIPINVITE message.

[0119] Step 303: Receive the response message returned by the second terminal in response to the second session invitation request, wherein the response message includes the location information of the second terminal.

[0120] In this example, the location information of the second terminal may include at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, and the access network type information corresponding to the second terminal.

[0121] Step 304: Determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal.

[0122] The specific implementation of determining whether the first terminal and the second terminal are connected to the same satellite, regarding the location information of the first terminal and the location information of the second terminal, can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0123] Step 305: If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0124] The satellite includes the first UPF.

[0125] It should be noted that the specific implementation of step 305 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0126] The communication method provided in this embodiment includes a first session invitation request from a first terminal to initiate an IMS call with a second terminal, which includes the location information of the first terminal. The response message returned by the second terminal in response to the second session invitation request also includes the location information of the second terminal. Based on the location information of the first terminal and the second terminal, it is quickly determined whether the first terminal and the second terminal are connected to the same satellite, which facilitates rapid subsequent processing based on the determination result.

[0127] Figure 4 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a first network element.

[0128] like Figure 4 As shown, the communication method may include the following steps:

[0129] Step 401: Receive a first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal, and the session invitation request includes the location information of the first terminal.

[0130] It should be noted that the specific implementation of step 401 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0131] Step 402: If the first session invitation request includes the location information of the first terminal, send a second session invitation request to the second terminal, wherein the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal.

[0132] In one example, the second session invitation request may be obtained by processing the first session invitation request.

[0133] As an example, a second session invitation request can be obtained by adding a location information request message to the first session invitation request.

[0134] In this example, it can be determined whether the session invitation request includes the location information of the first terminal device. If it is determined that the session invitation request includes the location information of the first terminal, a second session invitation request is sent to the second terminal. The second session invitation request includes a location information request message, which is used to instruct the second terminal to provide the location information of the second terminal.

[0135] Step 403: Receive a response message returned by the second terminal, wherein the response message includes the location information of the second terminal.

[0136] As an example, when a second terminal detects that it is connected to a satellite, it can carry its location information in the response message.

[0137] The satellite to which the second terminal is connected may include a base station.

[0138] As an example, when a second terminal device detects that it is connected to a base station on a satellite, it can carry the location information of the second terminal in the response message.

[0139] For details regarding the location information of the second terminal, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0140] Step 404: Determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal.

[0141] It should be noted that the specific implementation of step 404 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0142] Step 405: If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0143] It should be noted that the specific implementation of step 405 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0144] In this embodiment, the first terminal actively carries its own location information in the first session invitation request, and the second terminal carries its own location information in the response message it returns based on the location information request message carried in the second session invitation request. This allows the first network element to quickly determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal.

[0145] Figure 5 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a first network element.

[0146] like Figure 5 As shown, the communication method may include the following steps:

[0147] Step 501: Receive the first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0148] Step 502: Receive the response message returned by the second terminal in response to the second session invitation request.

[0149] It should be noted that the specific implementation methods of steps 501 and 502 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0150] Step 503: If the first session invitation request does not include the location information of the first terminal and / or the response message does not include the location information of the second terminal, a location query request is sent to the second network element, wherein the location query request is used to request the query of the location information of the first terminal and / or the second terminal.

[0151] Step 504: Receive the location query response message returned by the second network element, wherein the location query response message includes the location information of the first terminal and / or the second terminal.

[0152] In one embodiment of this disclosure, if the location information of the first terminal is not carried in the first session invitation request, but the location information of the second terminal is carried in the response message, a first location query request is sent to the second network element, and a first location query response message returned by the second network element in response to the first location query request is received. The first location query request is used to request to query the location information of the first terminal, and the first location query response message includes the location information of the first terminal.

[0153] In another embodiment of this disclosure, if the location information of the first terminal is carried in the first session invitation request but the location information of the second terminal is not carried in the response message, a second location query request is sent to the second network element, and a second location query response message returned by the second network element in response to the second location query request is received. The second location query request is used to request to query the location information of the second terminal, and the second location query response message includes the location information of the second terminal.

[0154] In another embodiment of this disclosure, if the location information of the first terminal is not carried in the first session invitation request and the location information of the second terminal is not carried in the response message, a third location query request is sent to the second network element, and a third location query response message returned by the second network element in response to the third location query request is received. The third location query request is used to request to query the location information of the first terminal and the second terminal, and the third location query response message includes the location information of the first terminal and the second terminal.

[0155] It should be noted that the second network element can subscribe to the location information of the first and second terminals from the Access and Mobility Management Function (AMF) network element. After the base station mounted on the satellite detects a change in the service message of the corresponding first and / or second terminal, it can send a location report to the AMF network element. Correspondingly, the AMF network element sends the location report to the second network element.

[0156] In one example, the location report includes one or more of the cell identifier of the cell where the first terminal and / or the second terminal is located, the base station identifier of the base station to which the first terminal and / or the second terminal is connected, and the access network type information of the first terminal and / or the second terminal.

[0157] Step 505: Determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal.

[0158] Step 506: If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0159] It should be noted that the specific implementation methods of steps 505 and 506 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0160] In this embodiment, by obtaining the location information of the first terminal and / or the second terminal from the second network element, it is possible to quickly determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal. This facilitates subsequent processing based on the determination result, thereby improving the efficiency of the first terminal and the second terminal directly forwarding media plane data during IMS calls via satellite.

[0161] Figure 6 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a first network element.

[0162] like Figure 6 As shown, the communication method may include the following steps:

[0163] Step 601: Receive a first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0164] It should be noted that the specific implementation of step 601 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0165] Step 602: Send a first location query request to the second network element. The first location query request is used to request the location information of the first terminal.

[0166] Step 603: Receive the first location query response message returned by the second network element in response to the first location query request, wherein the first location query response message includes the location information of the first terminal.

[0167] In this embodiment, after receiving the first session invitation request from the first terminal, regardless of whether the first session invitation request actively carries the location information of the first terminal, the location information of the first terminal can be obtained from the second network element.

[0168] For details regarding the location information of the first terminal, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0169] In one embodiment of this disclosure, a first authentication request (AAR) message can be sent to a second network element, and a first re-authentication request (RAR) message returned by the second network element in response to the first AAR message can be received. The first RAR message includes the location information of the first terminal, and the first AAR message includes a first location query request, which is used to request to query the location information of the first terminal.

[0170] Step 604: Send a second session invitation request to the second terminal.

[0171] In this example, the first session invitation request and the second session invitation request may be the same or different, and this embodiment does not specifically limit this.

[0172] Step 605: Receive the response message returned by the second terminal in response to the second session invitation request.

[0173] In one embodiment of this disclosure, the response message may carry the location information of the second terminal.

[0174] Step 606: Send a second location query request to the second network element. The second location query request is used to request the location information of the second terminal.

[0175] Step 607: Receive the second location query response message returned by the second network element in response to the second location query request, wherein the second location query response message includes the location information of the second terminal.

[0176] In one embodiment of this disclosure, in order to improve the accuracy of the location information of the second terminal, after receiving the response message returned by the second terminal in response to the second session invitation request, and regardless of whether the response message returned by the second terminal carries the location information of the second terminal, the location information of the second terminal can be obtained from the second network element.

[0177] In one embodiment of this disclosure, a second AAR message can be sent to a second network element, and a second RAR message can be received from the second network element in response to the second AAR message. The second AAR message includes a second location query request, which is used to request a query for the location information of the second terminal. The second RAR message includes the location information of the second terminal.

[0178] It should be noted that the description of the location information of the second terminal can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0179] Step 608: Determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal.

[0180] Step 609: If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0181] It should be noted that the specific implementation methods of steps 608 and 609 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0182] Based on the above description, it can be seen that in this embodiment, by communicating with the second network element, the location information of the first terminal and the second terminal can be quickly obtained, and the location information of the first terminal and the second terminal can be quickly used to determine whether the first terminal and the second terminal are connected to the same satellite, which facilitates subsequent processing based on the determination result.

[0183] Figure 7 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a first network element. It should also be noted that this embodiment is a further description of any of the foregoing embodiments.

[0184] like Figure 7 As shown, the communication method may include the following steps:

[0185] Step 701: Receive a first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0186] Step 702: Determine whether the first terminal and the second terminal are connected to the same satellite.

[0187] It should be noted that the specific implementation methods of steps 701 and 702 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0188] Step 703: If it is determined that the first terminal and the second terminal are connected to the same satellite, a message triggering the establishment of a QoS Flow for the first terminal and / or a message triggering the establishment of a QoS Flow for the second terminal is sent to the second network element. The message triggering the establishment of a QoS Flow for the first terminal and / or a message triggering the establishment of a QoS Flow for the second terminal includes an indication message, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0189] In one embodiment of this disclosure, a message triggering the establishment of a QoS Flow for the first terminal may be sent to a second network element, wherein the message triggering the establishment of a QoS Flow for the first terminal includes an indication message.

[0190] In one embodiment of this disclosure, a message triggering the establishment of a QoS Flow for a second terminal may be sent to a second network element, wherein the message triggering the establishment of a QoS Flow for a second terminal includes an indication message.

[0191] In one embodiment of this disclosure, a message triggering the establishment of a QoS Flow for a first terminal and a message triggering the establishment of a QoS Flow for a second terminal can be sent to a second network element, wherein the messages triggering the establishment of a QoS Flow for the first terminal and the messages triggering the establishment of a QoS Flow for the second terminal include indication messages.

[0192] In one embodiment of this disclosure, the message that triggers the establishment of the QoS Flow of the first terminal can be an AAR message that triggers the establishment of the QoS Flow of the first terminal or other types of messages, and this embodiment does not specifically limit it.

[0193] In one embodiment of this disclosure, the message that triggers the establishment of the QoS Flow of the second terminal can be an AAR message that triggers the establishment of the QoS Flow of the second terminal or other types of messages, and this embodiment does not specifically limit it.

[0194] Step 704: Receive a first QoS Flow establishment completion message sent by the second network element, wherein the first QoS Flow establishment completion message indicates that the QoS Flow of the first terminal has been established and carries the address information of the first UPF.

[0195] In one embodiment of this disclosure, after receiving messages triggering the establishment of a QoS Flow for a first terminal and messages triggering the establishment of a QoS Flow for a second terminal, the second network element may send messages requesting the establishment of a QoS Flow for the first terminal and a QoS Flow for the second terminal to the third network element. Correspondingly, after receiving the messages requesting the establishment of a QoS Flow for the first terminal and a QoS Flow for the second terminal, the third network element may create the QoS Flow for the first terminal and the QoS Flow for the second terminal based on the messages requesting the establishment of a QoS Flow for the first terminal and the QoS Flow for the second terminal, respectively.

[0196] In one embodiment of this disclosure, the message that triggers the establishment of a QoS Flow for the first terminal and / or the message that triggers the establishment of a QoS Flow for the second terminal further includes the call mode of an IMS call, wherein the call mode is an IMS voice call or an IMS video call.

[0197] In one embodiment of this disclosure, the message requesting the establishment of a QoS Flow for a first terminal and / or the message requesting the establishment of a QoS Flow for a second terminal may also carry the call method of an IMS call, wherein the call method is an IMS voice call or an IMS video call.

[0198] In the case of IMS voice call, the third network element can create a QoS Flow that can carry voice data in IMS voice call for the first terminal based on the message requesting the establishment of a QoS Flow for the first terminal, and can also create a QoS Flow that can carry voice data in IMS voice call for the second terminal based on the message triggering the establishment of a QoS Flow for the second terminal.

[0199] In this context, the 5G QoS identifier (5QI) of the QoS Flow used to carry voice data is equal to 1. That is, a QoS Flow with 5QI = 1 can be created to carry voice data.

[0200] In the case of IMS video call, the third network element can create a QoS Flow that can carry video data in the IMS video call for the first terminal based on the message requesting the establishment of a QoS Flow for the first terminal, and can also create a QoS Flow that can carry video data in the IMS video call for the second terminal based on the message triggering the establishment of a QoS Flow for the second terminal.

[0201] In this context, the 5G QoS identifier (5QI) of the QoS Flow used to carry video data is equal to 2. That is, a QoS Flow with 5QI = 2 can be created to carry video data via the QoS Flow.

[0202] Step 705: Send the address information of the first UPF to the first terminal.

[0203] In order to enable the first terminal to make IMS calls with the second terminal through the first UPF of the satellite, the address information of the first UPF can also be sent to the first terminal, so that the first terminal can make IMS calls with the second terminal based on the address information of the first UPF.

[0204] As an example, a response message returned by the second terminal can be sent to the first terminal, wherein the response message includes the address information of the first UPF, so that the first terminal can route the media plane data of the IMS call sent to the second terminal to the first UPF on the satellite based on the address information of the first UPF.

[0205] Step 706: Receive a second QoS Flow establishment completion message sent by the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established and carries the address information of the first UPF.

[0206] Step 707: Send the address information of the first UPF to the second terminal.

[0207] In order to enable the second terminal to make IMS calls with the first terminal through the first UPF of the satellite, the address information of the first UPF can also be sent to the second terminal, so that the second terminal can make IMS calls with the first terminal based on the address information of the first UPF.

[0208] As an example, a session update message can be sent to a second terminal, wherein the session update message includes the address information of a first user plane function (UPF) on the satellite, so that the second terminal can conduct an IMS call with the second terminal based on the address information of the first UPF.

[0209] Preferably, the session update message can be an updated session invitation request, wherein the updated session invitation request includes the address information of the first UPF, and the updated session invitation request is obtained by adding the address information of the first UPF to the first session invitation request.

[0210] For example, if the first session invitation request is a SIP INVITE message, the corresponding updated session invitation request can be an INVITE update message.

[0211] Figure 8 This is a schematic flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a second network element, or can be configured within a second network element. This embodiment uses the example of the communication method being executed by a second network element for illustrative purposes.

[0212] It should be noted that the second network element in this example can be a PCF network element in the 5G core network or other network elements that can use the communication methods provided in the embodiments of this disclosure.

[0213] like Figure 8 As shown, the communication method may include the following steps:

[0214] Step 801: Receive an indication message sent by the first network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, wherein the satellite includes a first user plane function (UPF), and the indication message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0215] It is understood that in this example, the first terminal and the second terminal are connected to the satellite, that is, the first terminal and the second terminal are connected to the same satellite.

[0216] In this embodiment, the satellite includes a first UPF.

[0217] It should be noted that the instruction message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0218] It should be noted that the description of the first network element determining whether the first terminal and the second terminal are connected to the same satellite can be found in other embodiments, and will not be repeated here.

[0219] In one embodiment of this disclosure, a message sent by a first network element to trigger the establishment of a QoS Flow for a first terminal and / or to trigger the establishment of a QoS Flow for a second terminal may be received, wherein the message to trigger the establishment of a QoS Flow for the first terminal and / or to trigger the establishment of a QoS Flow for the second terminal includes an indication message.

[0220] In one embodiment of this disclosure, the message that triggers the establishment of a QoS Flow for the first terminal and / or the message that triggers the establishment of a QoS Flow for the second terminal may further include the call mode of an IMS call, wherein the call mode is an IMS voice call or an IMS video call.

[0221] Step 802: Send an instruction message to the third network element.

[0222] In one embodiment of this disclosure, in order to enable a third network element to bind the identification information of the first terminal and the second terminal, and to manage the first terminal and the second terminal based on the binding relationship, the instruction message in this embodiment may include the identification information of the first terminal and the second terminal.

[0223] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0224] It should be noted that the relevant operations performed by the third network element after receiving the instruction message can be found in the relevant descriptions in other embodiments.

[0225] Based on the above description, it can be seen that in this embodiment, the second network element forwards the instruction message sent by the first network element to the third network element, thereby enabling the third network element to quickly know that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite. This facilitates subsequent processing based on these conditions, ultimately enabling the first terminal and the second terminal to directly conduct IMS calls via satellite. This reduces the transmission latency of the first terminal and the second terminal when conducting IMS calls via satellite communication networks, and improves the call efficiency between the two.

[0226] The communication method provided in this embodiment involves a second network element receiving an indication message sent by a first network element and forwarding the indication information to a third network element. This allows the third network element to easily determine, through the indication information, that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite. Consequently, the first terminal and the second terminal can directly conduct IMS calls via satellite, reducing the transmission latency of the first terminal and the second terminal when conducting IMS calls via satellite communication networks and improving the call efficiency between them.

[0227] Figure 9 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a second network element. Furthermore, this embodiment is a further detailed description of the foregoing embodiments.

[0228] like Figure 9 As shown, the communication method may include the following steps:

[0229] Step 901: Receive an indication message sent by the first network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, wherein the satellite includes a first user plane function (UPF), and the indication message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0230] For details on the specific implementation of step 901, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0231] Step 902: Send a message to the third network element requesting the establishment of a QoS Flow for the first terminal and / or a message requesting the establishment of a QoS Flow for the second terminal, wherein both the message triggering the establishment of the QoS Flow for the first terminal and the message triggering the establishment of the QoS Flow for the second terminal carry an indication message.

[0232] In one embodiment of this disclosure, in order to enable a third network element to bind the identification information of the first terminal and the second terminal, and to manage the first terminal and the second terminal based on the binding relationship, the instruction message in this embodiment may include the identification information of the first terminal and the second terminal.

[0233] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0234] In one embodiment of this disclosure, in order to enable the first terminal and the second terminal to conduct an IMS call, the message requesting the establishment of a QoS Flow for the first terminal and / or the message requesting the establishment of a QoS Flow for the second terminal further includes an IMS call mode, wherein the call mode is an IMS voice call or an IMS video call.

[0235] Step 903: Receive the first QoS Flow establishment completion message sent by the third network element, wherein the first QoS Flow establishment completion message indicates that the QoS Flow of the first terminal has been established.

[0236] Step 904: Send the first QoS Flow establishment completion message to the first network element, wherein the first QoS Flow establishment completion message carries the address information of the first UPF.

[0237] Step 905: Receive the second QoS Flow establishment completion message sent by the third network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established.

[0238] Step 906: Send the second QoS Flow establishment completion message to the first network element, wherein the second QoS Flow establishment completion message carries the address information of the first UPF.

[0239] In this embodiment, the second network element receives the indication message sent by the first network element and forwards the indication information to the third network element. This allows the third network element to easily know that the first terminal and the second terminal meet the conditions for IMS communication via satellite through the indication information. Consequently, the first terminal and the second terminal can directly communicate via satellite, reducing the transmission latency of the first terminal and the second terminal when communicating via satellite communication network and improving the communication efficiency between them.

[0240] In one embodiment of this disclosure, in order to enable the first network element to obtain the location information of the first terminal and / or the second terminal from the second network element, so as to determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal, the second network element in this embodiment can also receive a location query request sent by the first network element, wherein the location query request is used to query the location information of the first terminal and / or the second terminal; and send a location query response message to the first network element in response to the location query request, wherein the location query response message includes the location information of the first terminal and / or the second terminal.

[0241] In one embodiment of this disclosure, the second network element may further receive a first AAR message sent by the first network element, wherein the first AAR message includes a location query request for querying the location information of the first terminal and / or the second terminal; and send a first RAR message to the first network element in response to the first AAR message, wherein the first RAR message may include a location query response message including the location information of the first terminal and / or the second terminal. This allows the first network element to obtain the location information of the first terminal and / or the second terminal from the second network element.

[0242] In one embodiment of this disclosure, a second network element may receive a first AAR message sent by a first network element, wherein the first AAR message includes a first location query request, wherein the first location query request is used to query the location information of a first terminal; a first RAR message that sends the first AAR message to the first network element, wherein the first RAR message may include a first location query response message, wherein the first location query response message includes the location information of the first terminal; receive a second AAR message sent by the second network element, wherein the second AAR message includes a second location query request, wherein the second location query request is used to query the location information of a second terminal; and send a second RAR message that sends the second AAR message to the second network element, wherein the second RAR message may include a second location query response message, wherein the second location query response message includes the location information of the second terminal.

[0243] In one embodiment of this disclosure, the second network element may further receive a third AAR message sent by the first network element, wherein the third AAR message includes a location query request for querying the location information of the first terminal and the second terminal; and send a third RAR message to the first network element in response to the third AAR message, wherein the third RAR message may include a location query response message, wherein the location query response message includes the location information of the first terminal and the second terminal. Thus, the first network element can obtain the location information of the first terminal and the second terminal from the second network element.

[0244] It should be noted that, regarding the circumstances under which the first network element sends a location query request, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0245] In one embodiment of this disclosure, the location information of the first terminal and the location information of the second terminal are used by the first network element to determine whether the first terminal and the second terminal are connected to the same satellite.

[0246] Figure 10 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a third network element, or can be configured within a third network element. This embodiment uses the example of the communication method being executed by a third network element for illustrative purposes.

[0247] It should be noted that the third network element in this example can be an SMF network element in the 5G core network or other network elements that can use the communication methods provided in the embodiments of this disclosure.

[0248] like Figure 10As shown, the communication method may include the following steps:

[0249] Step 1001: Receive an indication message sent by the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0250] Both the first terminal and the second terminal are connected to the satellite.

[0251] The satellite includes the first UPF.

[0252] It should be noted that the description of the second network element receiving the instruction message can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0253] Step 1002: Send a notification message to the first UPF, wherein the notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0254] In one embodiment of this disclosure, after the third network element receives the indication information, it can know from the indication information that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite. At this time, the third network element can determine whether the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF. Correspondingly, if the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, a notification message is sent to the first UPF.

[0255] In one embodiment of this disclosure, if at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, the UPF of the IMS PUD session whose UPF is not the first UPF is modified to the first UPF, and a notification message is sent to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0256] In one embodiment of this disclosure, in order to enable the third network element to know the identification information of the first terminal and the second terminal, so as to facilitate subsequent management based on the identification information of the first terminal and the second terminal, the instruction information in this embodiment may also include the identification information of the first terminal and the second terminal.

[0257] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0258] In one embodiment of this disclosure, in order for the first UPF to know the identification information of the first terminal and the second terminal, so that the first UPF can bind the identification information of the first terminal and the second terminal to obtain the binding relationship between the two, and forward the media plane data of the first terminal and the second terminal during the IMS call based on the binding relationship, the notification message in this embodiment may also include the identification information of the first terminal and the second terminal.

[0259] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0260] The communication method provided in this embodiment involves a third network element receiving an indication message sent by a second network element. Based on this indication, the third network element learns that the first terminal and the second terminal meet the conditions for IMS communication via satellite, and that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF. The third network element then sends a notification message to the first UPF, enabling the first UPF to learn that the first terminal and the second terminal will conduct IMS communication via the first UPF. This allows the first UPF, which can use satellite communication, to directly forward media plane data during IMS communication between the first terminal and the second terminal, reducing transmission latency and improving communication efficiency.

[0261] Figure 11 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a third network element, or can be configured within a third network element. This embodiment uses the example of the communication method being executed by a third network element for illustrative purposes.

[0262] like Figure 11 As shown, the communication method may include the following steps:

[0263] Step 1101: Receive an indication message sent by the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0264] For details on the specific implementation of step 1101, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0265] Step 1102: If at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, modify the UPF of the IMS PUD session whose UPF is not the first UPF to the first UPF.

[0266] Step 1103: Send a notification message to the first UPF.

[0267] The notification message is used to notify the first UPF, the first terminal, and the second terminal that they will conduct an IMS call through the first UPF.

[0268] In one example of this disclosure, if it is determined that the UPF corresponding to the IMS PUD session of the first terminal is not the first UPF, while the UPF corresponding to the IMS PUD session of the second terminal is the first UPF, the IMS PUD session whose UPF is not the first UPF becomes the IMS PUD session of the first terminal. Correspondingly, the UPF corresponding to the IMS PUD session of the first terminal can be modified to the first UPF, so that the first terminal and the second terminal can directly conduct IMS calls through the first UPF deployed on the satellite.

[0269] In one example, the UPF corresponding to the IMS PUD session of the first terminal can be modified to the first UPF by initiating a modification process for the IMS PUD session of the first terminal.

[0270] It should be noted that the process of establishing the IMS PUD session for the first terminal can be found in the relevant technical descriptions, and will not be repeated here.

[0271] In another example of this disclosure, if it is determined that the UPF corresponding to the IMS PUD session of the first terminal is the first UPF, while the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, the IMS PUD session whose UPF is not the first UPF becomes the IMS PUD session of the second terminal. Correspondingly, the UPF corresponding to the IMS PUD session of the second terminal can be modified to the first UPF, so that the first terminal and the second terminal can directly conduct IMS calls through the first UPF deployed on the satellite.

[0272] It should be noted that the process of establishing an IMS PUD session for the second terminal can be found in the relevant technical descriptions, and will not be repeated here.

[0273] In one example, the UPF corresponding to the IMS PUD session of the second terminal can be modified to the first UPF by initiating a modification process for the IMS PUD session of the second terminal.

[0274] In another example of this disclosure, if it is determined that the UPF corresponding to the IMS PUD session of the first terminal is not the first UPF, and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal can both be modified to the first UPF, so that the first terminal and the second terminal can directly conduct IMS calls through the first UPF deployed on the satellite.

[0275] In one example, a modification process for the IMS PUD session of the second terminal can be initiated to modify the UPF corresponding to the IMS PUD session of the second terminal to the first UPF, and a modification process for the IMS PUD session of the first terminal can be initiated to modify the UPF corresponding to the IMS PUD session of the first terminal to the first UPF.

[0276] Based on the above description, it can be seen that in this embodiment, the third network element receives the instruction message sent by the second network element and sends a notification message to the first UPF, so that the first UPF can know through the notification message that the first terminal and the second terminal will conduct an IMS call through the first UPF. This enables the media plane data during the IMS call between the first terminal and the second terminal to be directly forwarded via satellite, reducing the transmission latency of the first terminal and the second terminal when conducting an IMS call through the satellite communication network and improving the call efficiency between the two.

[0277] Figure 12 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a third network element, or can be configured within a third network element. This embodiment uses the example of the communication method being executed by a third network element for illustrative purposes.

[0278] like Figure 12 As shown, the communication method may include the following steps:

[0279] Step 1201: Receive a message from the second network element requesting the establishment of a QoS Flow for the first terminal and / or a message requesting the establishment of a QoS Flow for the second terminal, wherein both the message requesting the establishment of a QoS Flow for the first terminal and the message requesting the establishment of a QoS Flow for the second terminal carry an indication message.

[0280] The instruction message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0281] Both the first terminal and the second terminal are connected to the satellite.

[0282] The satellite includes the first UPF.

[0283] Step 1202: Based on the message requesting the establishment of a QoS Flow for the first terminal, establish a QoS Flow for the first terminal to carry media plane data during IMS calls, and based on the message requesting the establishment of a QoS Flow for the second terminal, establish a QoS Flow for the second terminal to carry media plane data during IMS calls.

[0284] In one embodiment of this disclosure, the message requesting the establishment of a QoS Flow for a first terminal and / or the message requesting the establishment of a QoS Flow for a second terminal may also carry the call method of an IMS call, wherein the call method is an IMS voice call or an IMS video call.

[0285] In the case of IMS voice call, the third network element can create a QoS Flow that can carry voice data in IMS voice call for the first terminal based on the message requesting the establishment of a QoS Flow for the first terminal, and can also create a QoS Flow that can carry voice data in IMS voice call for the second terminal based on the message triggering the establishment of a QoS Flow for the second terminal.

[0286] In this context, the 5G QoS identifier (5QI) of the QoS Flow used to carry voice data is equal to 1. That is, a QoS Flow with 5QI = 1 can be created to carry voice data.

[0287] In the case of IMS video call, the third network element can create a QoS Flow that can carry video data in the IMS video call for the first terminal based on the message requesting the establishment of a QoS Flow for the first terminal, and can also create a QoS Flow that can carry video data in the IMS video call for the second terminal based on the message triggering the establishment of a QoS Flow for the second terminal.

[0288] In this context, the 5G QoS identifier (5QI) of the QoS Flow used to carry video data is equal to 2. That is, a QoS Flow with 5QI = 2 can be created to carry video data via the QoS Flow.

[0289] Step 1203: If the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are both the first UPF, send a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0290] Step 1204: If at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, modify the UPF of the IMS PUD session whose UPF is not the first UPF to the first UPF, and send a notification message to the first UPF.

[0291] Step 1205: Send a first QoS Flow establishment completion message and / or a second QoS Flow establishment completion message to the second network element, wherein the first QoS Flow establishment completion message indicates that the QoS Flow of the first terminal has been established and the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established. The first QoS Flow establishment completion message and / or the second QoS Flow establishment completion message include the address information of the first UPF.

[0292] The first QoS Flow establishment completion message is used to respond to the message requesting the establishment of the first terminal's QoS Flow. In other words, the first QoS Flow establishment completion message is a response message to the message requesting the establishment of the first terminal's QoS Flow.

[0293] It should be noted that the processing operations performed by the second network element after receiving the first QoS Flow establishment completion message can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0294] The second QoS Flow establishment completion message is used to respond to the message requesting the establishment of the second terminal's QoS Flow. In other words, the second QoS Flow establishment completion message is a response message to the message requesting the establishment of the second terminal's QoS Flow.

[0295] It should be noted that the processing operations performed by the second network element after receiving the second QoS Flow establishment completion message can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0296] Based on the above description, it can be seen that in this embodiment, a first QoS Flow establishment completion message and / or a second QoS Flow establishment completion message carrying the address information of the first UPF are sent to the second network element, so that the second network element sends the address information of the first UPF to the first terminal and the second terminal, thereby enabling the first terminal and the second terminal to conduct IMS calls based on the address information of the first UPF.

[0297] Figure 13 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a first terminal, or can be configured within a first terminal. This embodiment uses the example of the communication method being executed by a first terminal for illustrative purposes.

[0298] like Figure 13 As shown, the communication method may include the following steps:

[0299] Step 1301: Send a first session invitation request to the first network element, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0300] In this embodiment, the first session invitation request may carry information such as the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0301] As an example, the first session invitation request in this example can be a SIP INVITE message.

[0302] Step 1302: Receive a response message sent by the first network element in response to the first session invitation request. The response message carries the address information of the first user plane function (UPF) on the satellite. Both the first terminal and the second terminal are connected to the satellite.

[0303] In one embodiment of this disclosure, in order to enable the first network element to conveniently obtain the location information of the first terminal, so as to determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal, the first session invitation request may also carry the location information of the first terminal.

[0304] In one embodiment of this disclosure, in order to enable the first network element to conveniently obtain the location information of the first terminal, so as to determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal, the first session invitation request may also carry the location information of the first terminal when it detects that it is connected to the satellite.

[0305] In one embodiment of this disclosure, in order to enable the first network element to conveniently obtain the location information of the first terminal, so as to determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the second terminal, the first session invitation request may also carry the location information of the first terminal when it detects that it is connected to a base station on the satellite.

[0306] In one embodiment of this disclosure, the location information of the first terminal may include at least one of the following: cell identifier information of the cell where the first terminal is located, base station identifier of the base station to which the first terminal is connected, and access network type information corresponding to the first terminal.

[0307] In one embodiment of this disclosure, the location information of the first terminal is used by the first network element to determine whether the first terminal and the second terminal are connected to the same satellite.

[0308] It should be noted that the processing procedure performed by the first network element after receiving the first session invitation request can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0309] Step 1303: Make an IMS call based on the address information of the first UPF.

[0310] In this embodiment, after receiving the response message, the first terminal can determine that the current media plane address information is the address information of the first UPF based on the address information of the first UPF carried in the response message. Correspondingly, the first terminal can subsequently conduct IMS calls based on the address information of the first UPF. Specifically, the first terminal can send media plane data during the IMS call based on the address information of the first UPF.

[0311] Based on the above description, it can be seen that in this embodiment, the first terminal can easily obtain the address information of the first UPF on the satellite from the response message returned by the first network element in response to the first session invitation request. As a result, the first terminal can conduct IMS calls based on the address information, thereby realizing the direct forwarding of media plane data during the IMS call process via satellite. This reduces the transmission path between the first terminal and the second terminal when conducting IMS calls through the satellite network, reduces the transmission latency between the first terminal and the second terminal when conducting IMS calls through the satellite communication network, and improves the call efficiency between the two.

[0312] Figure 14 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a second terminal, or can be configured within a second terminal. This embodiment uses the example of the communication method being executed by a second terminal for illustrative purposes.

[0313] like Figure 14 As shown, the communication method may include the following steps:

[0314] Step 1401: Receive a second session invitation request sent by the first network element, wherein the second session invitation request is a request from the first terminal to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0315] As an example, the second session invitation request can be sent by the first network element after receiving the first session invitation request sent by the first terminal.

[0316] In this example, the first session invitation request and the second session invitation request can be the same or different. As an example, the second session invitation request can be obtained by the first network element processing the first session invitation request.

[0317] The processing procedure performed by the first network element after receiving the first session invitation request can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0318] For details regarding the information carried in the first session invitation request, please refer to the relevant descriptions in other implementation embodiments.

[0319] Step 1402: Send a response message to the first network element in response to the second session invitation request.

[0320] In one embodiment of this disclosure, in order to enable the first network element to conveniently obtain the location information of the second terminal, and to determine whether the first terminal and the second terminal are connected to the same satellite based on the location information of the second terminal, the response message in this embodiment may actively carry the location information of the second terminal.

[0321] As an example, when a second terminal detects that it is connected to a satellite, it can carry its location information in the response message.

[0322] As an example, if the second terminal detects that it is connected to a base station on a satellite, it can carry the location information of the second terminal in the response message.

[0323] In one embodiment of this disclosure, the location information of the second terminal is used by the first network element to determine whether the first terminal and the second terminal are connected to the same satellite.

[0324] Step 1403: Receive a session update message sent by the first network element. The session update message carries the address information of the first user plane function (UPF) on the satellite. The session update message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0325] Optionally, the session update message can be an updated first session invitation request.

[0326] The updated first session invitation request includes the address information of the first UPF, which is obtained by adding the address information of the first UPF to the first session invitation request.

[0327] In this case, the address information of the first UPF on the satellite is forwarded from the third network element to the first network element through the second network element.

[0328] The specific process by which the first network element obtains the address information of the first UPF on the satellite can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0329] Step 1404: Make an IMS call based on the address information of the first UPF.

[0330] In this embodiment, after receiving the session update message, the second terminal can determine that the current media plane address information is the address information of the first UPF based on the address information of the first UPF carried in the session update message. Correspondingly, the second terminal can subsequently conduct IMS calls based on the address information of the first UPF. Specifically, the second terminal can send media plane data during the IMS call based on the address information of the first UPF.

[0331] Based on the above description, it can be seen that in this embodiment, the second terminal can easily obtain the address information of the first UPF on the satellite from the session update message sent by the first network element. As a result, the second terminal can conduct IMS calls based on the address information, thereby realizing the direct forwarding of media plane data during the IMS call process through the satellite. This reduces the transmission path between the first terminal and the second terminal when conducting IMS calls through the satellite network, reduces the transmission latency between the first terminal and the second terminal when conducting IMS calls through the satellite communication network, and improves the call efficiency between the two.

[0332] Figure 15 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a second terminal, or can be configured within a second terminal. This embodiment uses the example of the communication method being executed by a second terminal for illustrative purposes.

[0333] like Figure 15 As shown, the communication method may include the following steps:

[0334] Step 1501: Receive a second session invitation request sent by the first network element, wherein the second session invitation request is a request from the first terminal to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal, wherein the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal.

[0335] Step 1502: Send a response message to the first network element in response to the second session invitation request, wherein the response message carries the location information of the second terminal.

[0336] Step 1503: Receive a session update message sent by the first network element. The session update message carries the address information of the first user plane function (UPF) on the satellite. The session update message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0337] Step 1504: Make an IMS call based on the address information of the first UPF.

[0338] Based on the above description, it can be seen that in this embodiment, the second terminal can easily obtain the address information of the first UPF on the satellite from the session update message sent by the first network element. As a result, the second terminal can conduct IMS calls based on the address information, thereby realizing the direct forwarding of media plane data during the IMS call process through the satellite. This reduces the transmission path between the first terminal and the second terminal when conducting IMS calls through the satellite network, reduces the transmission latency between the first terminal and the second terminal when conducting IMS calls through the satellite communication network, and improves the call efficiency between the two.

[0339] Figure 16 This is a flowchart illustrating another communication method provided in an embodiment of this disclosure. It should be noted that the communication method in this embodiment is executed by a communication device. It should also be noted that the method in this embodiment can be implemented by software and / or hardware. The communication device can be a satellite's first user plane function (UPF), or it can be configured within the satellite's first user plane function (UPF). This embodiment uses the example of the communication method being executed by the satellite's first user plane function (UPF) for illustrative purposes.

[0340] like Figure 16 As shown, the communication method may include the following steps:

[0341] Step 1601: Receive a notification message sent by the third network element, wherein the notification message is used to notify the first UPF, the first terminal, and the second terminal that they will conduct an IMS call through the first UPF.

[0342] It should be noted that the processing procedures performed by the third network element before sending the notification message can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0343] It should be noted that in this example, the first terminal and the second terminal are connected to the satellite, that is, the first terminal and the second terminal are connected to the same satellite.

[0344] In one embodiment of this disclosure, the satellite may further include a base station. As an example, a first terminal and a second terminal may be connected to the base station on the satellite.

[0345] In one embodiment of this disclosure, in order to enable the first UPF to know the identification information of the first terminal and the second terminal, and to establish a binding relationship between the two based on the identification information of the first terminal and the second terminal, and to forward the media plane data of the first terminal and the second terminal during IMS calls based on the binding relationship, the notification message in this embodiment may also include the identification information of the first terminal and the second terminal.

[0346] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0347] Step 1602: Receive the media plane data of the IMS call from the first terminal and forward the media plane data to the second terminal.

[0348] In one embodiment of this disclosure, step 1602 may further involve receiving media plane data of an IMS call from a second terminal and forwarding the media plane data to the first terminal.

[0349] In one example of this disclosure, the first UPF may include all or part of the functions of the Session Border Controller (SBC), such as media resource management, QoS policy control, security functions, and data encryption.

[0350] Based on the above description, it can be seen that in this embodiment, the first UPF can learn through a notification message that the first terminal and the second terminal will conduct an IMS call through the first UPF, and forward the media plane data of the IMS call between the first terminal and the second terminal. This allows the first UPF via the satellite to directly forward the media plane data during the IMS call between the first terminal and the second terminal, reducing the transmission path of the first terminal and the second terminal when conducting an IMS call through the satellite network, reducing the transmission latency of the first terminal and the second terminal when conducting an IMS call through the satellite communication network, and improving the call efficiency between the two.

[0351] Figure 17 This is a schematic diagram of the structure of a communication device provided in an embodiment of this disclosure. It should be noted that the communication device in this embodiment is used in a first network element.

[0352] like Figure 17 As shown, the communication device 1700 may include:

[0353] The receiving module 1701 is used to receive a first session invitation request from the first terminal, wherein the first session invitation request is used to request an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal.

[0354] The determination module 1702 is used to determine whether the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first user plane function (UPF).

[0355] The sending module 1703 is used to send an indication message to the second network element when it is determined that the first terminal and the second terminal are connected to the same satellite. The indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0356] In one embodiment of this disclosure, a message triggering the establishment of a QoS Flow for a first terminal and / or a message triggering the establishment of a QoS Flow for a second terminal are sent to a second network element, wherein both the message triggering the establishment of a QoS Flow for the first terminal and / or the message triggering the establishment of a QoS Flow for the second terminal carry an indication message.

[0357] In one embodiment of this disclosure, the instruction message includes identification information of the first terminal and the second terminal.

[0358] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0359] In one embodiment of this disclosure, the determining module 1702 is specifically used for:

[0360] Based on the location information of the first terminal and the location information of the second terminal, determine whether the first terminal and the second terminal are connected to the same satellite.

[0361] In one embodiment of this disclosure, the first session invitation request includes the location information of the first terminal; the sending module 1703 is further configured to send the second session invitation request to the second terminal; the receiving module 1701 is further configured to receive the response message returned by the second terminal in response to the second session invitation request, wherein the response message includes the location information of the second terminal.

[0362] In one embodiment of this disclosure, if the first session invitation request includes the location information of the first terminal, the sending module 1703 is further configured to send a second session invitation request to the second terminal, wherein the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal;

[0363] The receiving module 1701 is also used to receive a response message returned by the second terminal, wherein the response message includes the location information of the second terminal.

[0364] In one embodiment of this disclosure, the apparatus may further include: a first processing module, wherein the first processing module is configured to:

[0365] If the first session invitation request does not include the location information of the first terminal and / or the response message does not include the location information of the second terminal, a location query request is sent to the second network element, wherein the location query request is used to request to query the location information of the first terminal and / or the second terminal;

[0366] Receive a location query response message returned by the second network element, wherein the location query response message includes the location information of the first terminal and / or the second terminal.

[0367] In one embodiment of this disclosure, the apparatus further includes a second processing module, wherein the second processing module is configured to:

[0368] Send a first location query request to the second network element. The first location query request is used to request the location information of the first terminal.

[0369] Receive a first location query response message returned by the second network element in response to the first location query request, wherein the first location query response message includes the location information of the first terminal;

[0370] Send a second location query request to the second network element. The second location query request is used to request the location information of the second terminal.

[0371] The system receives a second location query response message returned by the second network element in response to the second location query request, wherein the second location query response message includes the location information of the second terminal.

[0372] In one embodiment of this disclosure, the location information of the first terminal includes at least one of the following: cell identifier information of the cell where the first terminal is located, base station identifier of the base station to which the first terminal is connected, and access network type information corresponding to the first terminal;

[0373] The location information of the second terminal includes at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, and the access network type information corresponding to the second terminal.

[0374] In one embodiment of this disclosure, the message that triggers the establishment of a QoS Flow for the first terminal and / or the message that triggers the establishment of a QoS Flow for the second terminal also carries the call method of the IMS call, wherein the call method is an IMS voice call or an IMS video call.

[0375] In one embodiment of this disclosure, the receiving module 1701 is further configured to: receive a first QoSFlow establishment completion message sent by a second network element, wherein the first QoSFlow establishment completion message indicates that the QoSFlow of the first terminal has been established, and the first QoSFlow establishment completion message carries the address information of the first UPF;

[0376] The sending module 1703 is also used to: send the address information of the first UPF to the first terminal;

[0377] The receiving module 1701 is further configured to: receive a second QoS Flow establishment completion message sent by the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message carries the address information of the first UPF;

[0378] The sending module 1703 is also used to send the address information of the first UPF to the second terminal.

[0379] It should be noted that the foregoing explanation of the communication method embodiments also applies to the communication device of this embodiment, and will not be repeated here.

[0380] The communication device provided in this embodiment determines whether the first terminal and the second terminal are connected to the same satellite when the first terminal requests an IMS call with the second terminal. The satellite includes a first UPF. If it is determined that the first terminal and the second terminal are connected to the same satellite, an indication message is sent to a second network element. This indication message indicates that the first terminal and the second terminal meet the conditions for conducting an IMS call via satellite. Therefore, the second network element can easily determine that the first terminal and the second terminal meet the conditions for conducting an IMS call via satellite through the indication information, enabling the first terminal and the second terminal to directly conduct an IMS call via satellite. This reduces the transmission latency when the first terminal and the second terminal conduct an IMS call via a satellite communication network and improves the call efficiency between them.

[0381] Figure 18 This is a schematic diagram of a communication device provided in an embodiment of the present disclosure. It should be noted that the communication device in this embodiment is used in a second network element.

[0382] like Figure 18 As shown, the communication device 1800 may include:

[0383] The receiving module 1801 is used to receive an indication message sent by the first network element. The indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite. The satellite includes a first user plane function (UPF). The indication message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0384] The sending module 1802 is used to send an indication message to the third network element.

[0385] Both the first terminal and the second terminal are connected to the satellite.

[0386] In one embodiment of this disclosure, a message requesting the establishment of a QoS flow for a first terminal and a message requesting the establishment of a QoS flow for a second terminal are sent to a third network element. Both the message requesting the establishment of a QoS flow for the first terminal and the message requesting the establishment of a QoS flow for the second terminal carry an indication message.

[0387] In one embodiment of this disclosure, the message requesting the establishment of a QoS Flow for a first terminal and / or the message requesting the establishment of a QoS Flow for a second terminal further includes the call mode of an IMS call, wherein the call mode is an IMS voice call or an IMS video call.

[0388] In one embodiment of this disclosure, the instruction message includes identification information for both the first and second terminals. This identification information may be other terminal-identifying information such as an IP address, an International Mobile Subscriber Identity (IMSI) number, and / or a Subscription Permanent Identity (SUPI).

[0389] In one embodiment of this disclosure, the receiving module 1801 is further configured to receive a location query request sent by the first network element, wherein the location query request is used to query the location information of the target terminal;

[0390] The sending module 1802 is further configured to send a location query response message to the first network element in response to the location query request, wherein the location query response message includes the location information of the target terminal, wherein the target terminal is the first terminal and / or the second terminal.

[0391] In one embodiment of this disclosure, the receiving module 1801 is further configured to: receive a first QoSFlow establishment completion message and / or a second QoSFlow establishment completion message sent by a third network element, wherein the first QoSFlow establishment completion message indicates that the QoSFlow of the first terminal has been established, the second QoSFlow establishment completion message indicates that the QoSFlow of the second terminal has been established, and the first QoSFlow establishment completion message and / or the second QoSFlow establishment completion message includes the address information of the first UPF;

[0392] The sending module 1802 is also used to: send the first QoS Flow establishment completion message and / or the second QoS Flow establishment completion message to the first network element.

[0393] It should be noted that the foregoing explanation of the communication method embodiments also applies to the communication device of this embodiment, and will not be repeated here.

[0394] The communication device provided in this embodiment receives an indication message sent by a first network element and forwards the indication information to a third network element. This allows the third network element to easily determine, through the indication information, that the first terminal and the second terminal meet the conditions for IMS communication via satellite. Consequently, the first terminal and the second terminal can directly communicate via satellite, reducing the transmission latency of the first terminal and the second terminal when communicating via satellite communication network and improving the communication efficiency between them.

[0395] Figure 19 This is a schematic diagram of a communication device provided in an embodiment of the present disclosure. It should be noted that the communication device in this embodiment is used in a third network element.

[0396] like Figure 19 As shown, the communication device 1900 may include:

[0397] The receiving module 1901 is used to receive an indication message sent by the second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS communication via satellite, wherein the satellite includes a first user plane function (UPF).

[0398] The sending module 1902 is used to send a notification message to the first UPF, wherein the notification message is used to notify the first UPF, the first terminal, and the second terminal that they will conduct an IMS call through the first UPF.

[0399] In one embodiment of this disclosure, the apparatus may further include: a modification module, configured to modify the UPF of the IMS PUD session whose UPF is not the first UPF to the first UPF if at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF.

[0400] In one embodiment of this disclosure, a message requesting the establishment of a QoS Flow for a first terminal and / or a message requesting the establishment of a QoS Flow for a second terminal sent by a second network element is received, wherein the message requesting the establishment of a QoS Flow for the first terminal and / or the message requesting the establishment of a QoS Flow for the second terminal includes an indication message.

[0401] In one embodiment of this disclosure, the message requesting the establishment of a QoS Flow for a first terminal and / or the message requesting the establishment of a QoS Flow for a second terminal further includes: the call mode of an IMS call, wherein the call mode is an IMS voice call or an IMS video call.

[0402] In one embodiment of this disclosure, both the notification message and the instruction message include identification information for the first terminal and the second terminal. This identification information may be other information that can identify the terminal, such as an IP address, an International Mobile Subscriber Identity (IMSI) number, and / or a Subscription Permanent Identity (SUPI).

[0403] In one embodiment of this disclosure, the sending module 1902 is further configured to:

[0404] Send a first QoS Flow establishment completion message and / or a second QoS Flow establishment completion message to the second network element, wherein the first QoS Flow establishment completion message indicates that the QoS Flow of the first terminal has been established and the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the first QoS Flow establishment completion message and / or the second QoS Flow establishment completion message includes the address information of the first UPF.

[0405] It should be noted that the foregoing explanation of the communication method embodiments also applies to the communication device of this embodiment, and will not be repeated here.

[0406] The communication device provided in this embodiment receives an indication message sent by a second network element. Based on this indication information, it learns that the first terminal and the second terminal meet the conditions for conducting IMS communication via satellite, and that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF. The device then sends a notification message to the first UPF, enabling the first UPF to learn that the first terminal and the second terminal will conduct IMS communication via the first UPF. This allows the first UPF, which can use the satellite, to directly forward media plane data during the IMS communication process between the first terminal and the second terminal, reducing the transmission latency of the first terminal and the second terminal during IMS communication via the satellite communication network and improving the communication efficiency between them.

[0407] Figure 20 This is a schematic diagram of a communication device provided in an embodiment of the present disclosure. It should be noted that the communication device in this embodiment is used in a first terminal.

[0408] like Figure 20 As shown, the communication device 2000 may include:

[0409] The first sending module 2001 is used to send a first session invitation request to the first network element, wherein the first session invitation request is used to request to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal;

[0410] The receiving module 2002 is used to receive a response message sent by the first network element in response to the first session invitation request. The response message carries the address information of the first user plane function (UPF) on the satellite. Both the first terminal and the second terminal are connected to the satellite.

[0411] The IMS call module 2003 is used to make IMS calls based on the address information of the first UPF.

[0412] In one embodiment of this disclosure, upon detecting that it is connected to a satellite, the first session invitation request carries the location information of the first terminal.

[0413] In one embodiment of this disclosure, the location information of the first terminal includes at least one of the following: cell identifier information of the cell where the first terminal is located, base station identifier of the base station to which the first terminal is connected, and access network type information corresponding to the first terminal.

[0414] It should be noted that the foregoing explanation of the communication method embodiment also applies to the communication device of this embodiment, and will not be repeated here.

[0415] The communication device provided in this embodiment can conveniently obtain the address information of the first UPF on the satellite from the response message returned by the first network element in response to the first session invitation request. As a result, the first terminal can make an IMS call based on the address information, thereby realizing the forwarding of media plane data during the IMS call through the first UPF on the satellite. This reduces the transmission path between the first terminal and the second terminal when making an IMS call through the satellite network, reduces the transmission latency between the first terminal and the second terminal when making an IMS call through the satellite communication network, and improves the call efficiency between the two.

[0416] Figure 21 This is a schematic diagram of a communication device provided in an embodiment of the present disclosure. It should be noted that the communication device in this embodiment is used in a second terminal.

[0417] like Figure 21 As shown, the communication device 2100 may include:

[0418] The first receiving module 2101 is used to receive a second session invitation request sent by the first network element, wherein the second session invitation request is a request from the first terminal to conduct an Internet Protocol Multimedia Subsystem (IMS) call with the second terminal;

[0419] The first sending module 2102 is used to send a response message to the first network element in response to the second session invitation request;

[0420] The second receiving module 2103 is used to receive a session update message sent by the first network element. The session update message carries the address information of the first user plane function (UPF) on the satellite. The session update message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite.

[0421] IMS call module 2104 is used to make IMS calls based on the address information of the first UPF.

[0422] In one embodiment of this disclosure, the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal, and the response message carries the location information of the second terminal.

[0423] In one embodiment of this disclosure, upon detecting that it is connected to a satellite, the response message carries the location information of the second terminal.

[0424] In one embodiment of this disclosure, the location information of the second terminal includes at least one of the following: cell identifier information of the cell where the second terminal is located, base station identifier of the base station to which the second terminal is connected, and access network type information corresponding to the second terminal.

[0425] It should be noted that the foregoing explanation of the communication method embodiments also applies to the communication device of this embodiment, and will not be repeated here.

[0426] The communication device provided in this embodiment can conveniently obtain the address information of the first UPF on the satellite from the session update message sent by the first network element. As a result, the second terminal can make IMS calls based on the address information, thereby realizing the forwarding of media plane data during the IMS call process through the first UPF on the satellite. This reduces the transmission path between the first terminal and the second terminal when making IMS calls through the satellite network, reduces the transmission latency between the first terminal and the second terminal when making IMS calls through the satellite communication network, and improves the call efficiency between the two.

[0427] Figure 22 This is a schematic diagram of a communication device provided in an embodiment of the present disclosure. It should be noted that the communication device in this embodiment is used in the first user plane function (UPF) of a satellite.

[0428] like Figure 22 As shown, the communication device 2200 may include:

[0429] The first receiving module 2201 is used to receive a notification message sent by the third network element, wherein the notification message is used to notify the first UPF, the first terminal, and the second terminal that they will conduct an IMS call through the first UPF.

[0430] The second receiving module 2202 is used to receive media plane data of the IMS call of the first terminal and forward the media plane data to the second terminal, or to receive media plane data of the IMS call of the second terminal and forward the media plane data to the first terminal.

[0431] In one embodiment of this disclosure, the notification message carries identification information of the first terminal and the second terminal.

[0432] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0433] It should be noted that the foregoing explanation of the communication method embodiment also applies to the communication device of this embodiment, and will not be repeated here.

[0434] The communication device provided in this embodiment can learn through a notification message that a first terminal and a second terminal will conduct an IMS call through a first UPF, and forward the media plane data of the IMS call between the first terminal and the second terminal. This allows the media plane data during the IMS call between the first terminal and the second terminal to be directly forwarded through the first UPF of the satellite, reducing the transmission path of the first terminal and the second terminal when conducting an IMS call through the satellite network, reducing the transmission latency of the first terminal and the second terminal when conducting an IMS call through the satellite communication network, and improving the call efficiency between the two.

[0435] Figure 23 This is a schematic diagram of the structure of a communication system provided in an embodiment of the present disclosure.

[0436] like Figure 23 As shown, the communication system 2300 may include a first terminal 2301, a second terminal 2302, a first user plane function UPF 23031 on a satellite 2303, a first network element 2304, a second network element 2305, and a third network element 2306, wherein:

[0437] The first network element 2304 is used to implement the communication method disclosed in the first aspect embodiment of this disclosure;

[0438] The second network element 2305 is used to implement the communication method disclosed in the second aspect embodiment of this disclosure;

[0439] The third network element 2306 is used to implement the communication method disclosed in the third aspect embodiment of this disclosure;

[0440] The first terminal 2301 is used to implement the communication method disclosed in the fourth aspect embodiment of this disclosure;

[0441] The second terminal 2302 is used to implement the communication method disclosed in the fifth aspect embodiment of this disclosure;

[0442] The first UPF23031 is used to implement the communication method disclosed in the sixth aspect embodiment of this disclosure.

[0443] It should be noted that the foregoing explanation of the communication method embodiments also applies to the communication device of this embodiment, and will not be repeated here.

[0444] The communication system provided in this embodiment determines whether the first terminal and the second terminal are connected to the same satellite when the first terminal requests an IMS call with the second terminal. If it is determined that the first terminal and the second terminal are connected to the same satellite, the PCF sends an indication message to the third network element. This allows the third network element to know, based on the indication message, that the first terminal and the second terminal meet the conditions for conducting an IMS call through the first UPF on the satellite. If the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, the third network element sends a notification message to the first UPF. This allows the first UPF to know that the first terminal and the second terminal will conduct an IMS call through the first UPF. This enables the first UPF to directly forward the media plane data during the IMS call between the first terminal and the second terminal, reducing the transmission latency when the first terminal and the second terminal conduct an IMS call through the satellite communication network and improving the call efficiency between them.

[0445] To facilitate a clear understanding of this disclosure, the following will be combined with... Figure 23 The interaction process between the first terminal, the second terminal, the first network element, the third network element, the second network element, and the first UPF on the satellite in the communication system is described exemplarily. It should be noted that this embodiment uses the first network element as the Proxy Call Session Control Function (P-CSCF) network element, the second network element as the Policy Control Function (PCF) network element, and the third network element as the Session Management Function (SMF) network element as examples for exemplary description.

[0446] Figure 24 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the PCF network element, the SMF network element, and the first UPF on the satellite. Figure 1 .

[0447] like Figure 24 As shown, the method may include:

[0448] Step 2401: The first terminal sends a first session invitation request to the P-CSCF network element.

[0449] The first session invitation request carries all or part of the following information: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, the Session Description Protocol (SDP), and the location information of the first terminal. In other words, the first session invitation request may include at least one or more of the following information: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0450] The SDP contains the media address of the first terminal and the media types and encoding / decoding information supported by the first terminal.

[0451] The SDP (Session Description Protocol) is primarily used for media negotiation before a session begins. The media address is the address used to send and receive media streams.

[0452] Optionally, the location information of the first terminal may include at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, and the access network type information corresponding to the first terminal.

[0453] Optionally, the identification information can be in the format of a Session Initiation Protocol Uniform Resource Identifier (SIP-URI) or a Telephone Uniform Resource Identifier (Tel-URI).

[0454] Optionally, SDP also includes the required bandwidth information, which the network side uses to determine the required Quality of Service (QoS) bandwidth for the dedicated load.

[0455] Step 2402: The P-CSCF network element sends a second session invitation request to the second terminal.

[0456] In this example, the first session invitation request and the second session invitation request may be the same or different.

[0457] As an example, the first session invitation request can be obtained by processing the first session invitation request.

[0458] In this example, the second session invitation request also carries the media plane address and port information of the called session border controller (SBC) corresponding to the second terminal, as well as SDP information.

[0459] The Session Border Controller (SBC) in this disclosure can also be referred to as the Internet Protocol Multimedia Subsystem Access Gateway (IMS Access Gateway, IMS AGW).

[0460] Step 2403: The P-CSCF network element receives the 183 message returned by the second terminal in response to the second session invitation request.

[0461] In this example, message 183 is the response message to the second session invitation request.

[0462] The 183 message may include an SDP response message and the location information of the second terminal.

[0463] The SDP response message contains information about the media types and codecs supported by the called UE.

[0464] In this example, the location information of the second terminal may include at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, and the access network type information corresponding to the second terminal.

[0465] Step 2404: The P-CSCF network element checks whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal. If so, steps 2405 and 2408 are executed.

[0466] In this example, the satellite is equipped with a first user plane function (UPF).

[0467] Step 2405: The P-CSCF network element sends a first AAR message to the PCF network element. The first AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first AAR message includes an indication message, which indicates that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0468] The instruction message contains identification information for both the first and second terminals.

[0469] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0470] In one embodiment of this disclosure, the first AAR message further includes: a call mode for the first terminal and the second terminal to conduct an IMS call, wherein the call mode is either an IMS voice call or an IMS video call.

[0471] Step 2406: The PCF network element sends a first request message to the SMF network element. The first request message is used to establish a Quality of Service Flow (QoSFlow) for the first terminal to carry voice data during IMS voice calls. The first request message includes an indication message, which indicates that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0472] The instruction message contains identification information for both the first and second terminals.

[0473] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0474] In this context, the 5G QoS identifier (5QI) of the QoS Flow used to carry voice data is equal to 1. That is, a QoS Flow with 5QI = 1 can be created to carry voice data.

[0475] In one embodiment of this disclosure, the first request message further includes: a call method for the first terminal and the second terminal to conduct an IMS call, wherein the call method is either an IMS voice call or an IMS video call.

[0476] Step 2407: The SMF network element initiates the establishment of the QoS Flow for the first terminal based on the first request message, and after learning from the indication information carried in the first request message that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, it checks whether the UPF corresponding to the IMSPUD session of the first terminal is the first UPF.

[0477] The process of establishing the QoS Flow for the first terminal can be found in the descriptions in relevant technologies, and will not be repeated here.

[0478] Step 2408: The P-CSCF network element sends a second AAR message to the PCF network element. The second AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second AAR message includes an indication message, which indicates that the second terminal meets the conditions for conducting IMS calls via satellite.

[0479] The instruction message contains the identification information of the second terminal and the second terminal.

[0480] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0481] Step 2409: Send a second request message to the SMF network element through the PCF network element. The second request message is used to establish a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second request message includes an indication message, which is used to indicate that the second terminal meets the conditions for conducting IMS calls via satellite.

[0482] Step 2410: The SMF network element initiates the establishment of the QoS Flow for the second terminal based on the second request message, and after learning from the indication information carried in the second request message that the second terminal meets the conditions for IMS communication via satellite, it checks whether the UPF corresponding to the IMS PUD session of the second terminal is the first UPF.

[0483] Step 2411: When the SMF network element determines that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, it sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0484] The notification message contains identification information for both the first and second terminals.

[0485] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0486] Step 2412: If the SMF network element determines that at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, it modifies the UPF of the IMS PUD session that is not the first UPF to the first UPF and sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS calls through the first UPF.

[0487] The notification message contains identification information for both the first and second terminals.

[0488] The identification information can be other identifiable terminal information such as IP address, International Mobile Subscriber Identity (IMSI) number and / or Subscription Permanent Identity (SUPI).

[0489] It should be noted that the specific implementation of step 2410 can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0490] Step 2413: The SMF network element sends a QoS Flow establishment completion message for the first terminal to the P-CSCF network element through the PCF network element. The message carries the address information of the first UPF.

[0491] Step 2414: The SMF network element sends a QoS Flow establishment completion message for the second terminal to the P-CSCF network element through the PCF network element. This message carries the address information of the first UPF.

[0492] Step 2415: The P-CSCF network element sends a 183 message carrying the address information of the first UPF to the first terminal.

[0493] In this embodiment, after receiving the 183 message, the first terminal can determine that the current media plane address information is the address information of the first UPF based on the address information of the first UPF carried in the 183 message. Correspondingly, the first terminal can subsequently conduct IMS calls based on the address information of the first UPF. Specifically, the first terminal can send media plane data during the IMS call based on the address information of the first UPF.

[0494] Step 2416: The P-CSCF network element sends a session update message to the second terminal, wherein the session update message includes the address information of the first UPF.

[0495] Optionally, the session update message can be an updated first session invitation request, wherein the updated first session invitation request includes the address information of the first UPF, and the updated first session invitation request is obtained by adding the address information of the first UPF to the first session invitation request.

[0496] It should be noted that the first UPF in this example implements some or all of the SBC's functions, such as media resource management, QoS policy control, security functions, and data encryption.

[0497] In this embodiment, after receiving the session update message, the second terminal can determine that the current media plane address information is the address information of the first UPF based on the address information of the first UPF carried in the session update message. Correspondingly, the second terminal can subsequently conduct IMS calls based on the address information of the first UPF. Specifically, the second terminal can send media plane data during the IMS call based on the address information of the first UPF.

[0498] Step 2417: The first terminal and the second terminal complete the session establishment.

[0499] In this example, the process of establishing a session between the first and second terminals is as follows: After receiving the 183 message, the first terminal replies with a Provisional Response Acknowledgement (PRACK) message. After sending PRACK to acknowledge the 183 message, the first terminal checks whether the dedicated audio QoS stream has been established (the corresponding NAS messages are PDU Session Modification Command and PDU Session Modification Complete). If it has been established, it means that the resource reservation on the calling side has been completed, satisfying the precondition. The first terminal needs to send an UPDATE request to modify the resource status in the SDP. When the second terminal detects the establishment of the audio-related dedicated transport, it returns a 200 signaling response to UPDATE. The first terminal receives a 180 Ringing provisional response indicating that it is notifying the recipient of the voice call establishment request, and the second terminal in the call starts ringing. When the called user answers, the second terminal returns a 200 acknowledgment command for the session invitation request as the final response to the session invitation request. The first terminal needs to send an ACK to confirm, and the session is now established.

[0500] Step 2418: After the session is established, the first terminal and the second terminal can forward media plane data during the IMS call through the first UPF on the satellite.

[0501] In other words, the media plane data of the first and second terminals are directly relayed through the first UPF on the satellite.

[0502] Based on the above description, it can be seen that in this embodiment, when it is determined that the first terminal and the second terminal are under the same satellite coverage, the UPF corresponding to the IMS PUD session of the first terminal and the second terminal is modified to the first UPF on the satellite. Thus, the first terminal and the second terminal can forward the IMS media plane data during the IMS call through the first UPF on the satellite, realizing that the media plane data does not land, reducing the transmission latency of the IMS media plane data during the IMS call, and improving the call efficiency when the two make an IMS call.

[0503] Figure 25 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the PCF network element, the SMF network element, and the first UPF on the satellite. Figure 2 .

[0504] Step 2501: The first terminal sends a first session invitation request to the P-CSCF network element.

[0505] The first session invitation request carries at least one of the following: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, the Session Description Protocol (SDP), and the location information of the first terminal.

[0506] Optionally, the first terminal can check whether it is connected to the satellite. If it finds that it is connected to the satellite, the first terminal can carry its location information in the first session invitation request sent to the P-CSCF network element.

[0507] The SDP contains the media address of the first terminal and the media types and encoding / decoding information supported by the first terminal.

[0508] SDP (Session Description Protocol) is primarily used for media negotiation before a session begins. The media address is the address used to send and receive media streams.

[0509] Optionally, the location information of the first terminal may include at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, and the access network type information corresponding to the first terminal.

[0510] Optionally, the identification information can be in the format of a Session Initiation Protocol Uniform Resource Identifier (SIP-URI) or a Telephone Uniform Resource Identifier (Tel-URI).

[0511] Optionally, SDP also includes the required bandwidth information, which the network side uses to determine the QoS bandwidth required for the dedicated load.

[0512] Step 2502: If the session invitation request includes the location information of the first terminal, the P-CSCF network element sends a second session invitation request to the second terminal. The second session invitation request includes a location information request message, which is used to instruct the second terminal to provide the location information of the second terminal.

[0513] Specifically, the P-CSCF network element detects whether the first session invitation request contains the location information of the first terminal. If the first session invitation request contains the location information of the first terminal, the P-CSCF network element adds a location information request message to the first session invitation request to obtain the second session invitation request, and sends the second session invitation request to the second terminal.

[0514] The second session invitation request also carries the media plane address and port information of the called session border controller (SBC) corresponding to the second terminal, as well as SDP information.

[0515] Step 2503: The P-CSCF network element receives the 183 message returned by the second terminal in response to the second session invitation request, wherein the 183 message includes the location information of the second terminal.

[0516] Optionally, after receiving the second session invitation request, the second terminal can detect whether it is connected to the satellite. If it detects that it is connected to the satellite, it sends a 183 message to the P-CSCF network element, wherein the 183 message includes the location information of the second terminal.

[0517] In this example, message 183 is the response message to the second session invitation request.

[0518] The 183 message may include an SDP response message and the location information of the second terminal.

[0519] The SDP response message contains information about the media types and codecs supported by the called UE.

[0520] In this example, the location information of the second terminal may include at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, and the access network type information corresponding to the second terminal.

[0521] Step 2504: The P-CSCF network element checks whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal. If so, and if it is determined that the IMS call is an IMS voice call, steps 2505 and 2508 are executed.

[0522] In this example, the satellite is equipped with a first user plane function (UPF).

[0523] Step 2505: The P-CSCF network element sends a first AAR message to the PCF network element. The first AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first AAR message includes an indication message, which indicates that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0524] Step 2506: Send a first request message to the SMF network element through the PCF network element. The first request message is used to establish a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first request message includes an indication message, which is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0525] Step 2507: The SMF network element initiates the establishment of the QoS Flow for the first terminal based on the first request message, and after learning from the indication information carried in the first request message that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, it checks whether the UPF corresponding to the IMSPUD session of the first terminal is the first UPF.

[0526] Step 2508: The P-CSCF network element sends a second AAR message to the PCF network element. The second AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second AAR message includes an indication message, which indicates that the second terminal meets the conditions for conducting IMS calls via satellite.

[0527] Step 2509: The PCF network element sends a second request message to the SMF network element. The second request message is used to establish a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second request message includes an indication message, which indicates that the second terminal meets the conditions for conducting IMS calls via satellite.

[0528] Step 2510: The SMF network element initiates the establishment of the QoS Flow for the second terminal based on the second request message, and after learning from the indication information carried in the second request message that the second terminal and the second terminal meet the conditions for IMS communication via satellite, it checks whether the UPF corresponding to the IMS PUD session of the second terminal is the first UPF.

[0529] Step 2511: When the SMF network element determines that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, it sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0530] Step 2512: If the SMF network element determines that at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, it modifies the UPF of the IMS PUD session that is not the first UPF to the first UPF and sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS calls through the first UPF.

[0531] Step 2513: The SMF network element sends a QoS Flow establishment completion message for the first terminal to the P-CSCF network element through the PCF network element. The message carries the address information of the first UPF.

[0532] Step 2514: The SMF network element sends a QoS Flow establishment completion message for the second terminal to the P-CSCF network element through the PCF network element. This message carries the address information of the first UPF.

[0533] Step 2515: The P-CSCF network element sends a 183 message carrying the address information of the first UPF to the first terminal.

[0534] Step 2516: The P-CSCF network element sends a session update message to the second terminal, wherein the session update message includes the address information of the first UPF.

[0535] Step 2517: The first terminal and the second terminal complete the session establishment.

[0536] Step 2518: After the session is established, the first terminal and the second terminal can forward the media plane data during the IMS call through the first UPF on the satellite.

[0537] It should be noted that for a detailed description of steps 2505 to 2518, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0538] Figure 26 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the SMF network element, the PCF network element, and the first UPF on the satellite. Figure 3 .

[0539] like Figure 26 As shown, the method may include:

[0540] Step 2601: The first terminal sends a first session invitation request to the P-CSCF network element.

[0541] The first session invitation request carries at least one of the following: the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0542] The SDP contains the media address of the first terminal and the media types and encoding / decoding information supported by the first terminal.

[0543] SDP (Session Description Protocol) is primarily used for media negotiation before a session begins. The media address is the address used to send and receive media streams.

[0544] Optionally, the identification information can be in the format of a Session Initiation Protocol Uniform Resource Identifier (SIP-URI) or a Telephone Uniform Resource Identifier (Tel-URI).

[0545] Optionally, SDP also includes the required bandwidth information, which the network side uses to determine the QoS bandwidth required for the dedicated load.

[0546] Step 2602: The P-CSCF network element sends a second session invitation request to the second terminal.

[0547] The specific implementation method of the P-CSCF network element sending the second session invitation request to the second terminal can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0548] Step 2603: The P-CSCF network element receives the 183 message returned by the second terminal in response to the second session invitation request.

[0549] In this example, message 183 is the response message to the second session invitation request.

[0550] The 183 message may include an SDP response message.

[0551] The SDP response message contains information about the media types and codecs supported by the called UE.

[0552] Step 2604: If the first session invitation request does not include the location information of the first terminal and / or the response message does not include the location information of the second terminal, the P-CSCF network element sends a location query request to the PCF network element, wherein the location query request is used to query the location information of the first terminal and / or the second terminal.

[0553] Step 2605: The P-CSCF network element receives the location query response message returned by the PCF network element in response to the location query request, wherein the location query response message includes the location information of the first terminal and / or the second terminal.

[0554] Step 2606: Check whether the first terminal and the second terminal are connected to the same satellite based on the location information of the first terminal and the location information of the second terminal, and then execute steps 2607 and 2610.

[0555] Step 2607: The P-CSCF network element sends a first AAR message to the PCF network element. The first AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first AAR message includes an indication message, which indicates that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0556] Step 2608: Send a first request message to the SMF network element through the PCF network element. The first request message is used to establish a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first request message includes an indication message, which is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0557] Step 2609: The SMF network element initiates the establishment of the QoS Flow for the first terminal based on the first request message, and after learning from the indication information carried in the first request message that the first terminal and the second terminal meet the conditions for IMS communication via satellite, it checks whether the UPF corresponding to the IMS PUD session of the first terminal is the first UPF.

[0558] Step 2610: The P-CSCF network element sends a second AAR message to the PCF network element. The second AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second AAR message includes an indication message, which indicates that the second terminal meets the conditions for conducting IMS calls via satellite.

[0559] Step 2611: The PCF network element sends a second request message to the SMF network element. The second request message is used to establish a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second request message includes an indication message, which is used to indicate that the second terminal meets the conditions for conducting IMS calls via satellite.

[0560] Step 2612: The SMF network element initiates the establishment of the QoS Flow for the second terminal based on the second request message. After learning from the indication information carried in the second request message that the second terminal meets the conditions for IMS communication via satellite, it checks whether the UPF corresponding to the IMS PUD session of the second terminal is the first UPF.

[0561] Step 2613: When the SMF network element determines that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, it sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0562] Step 2614: If the SMF network element determines that at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, it modifies the UPF of the IMS PUD session whose UPF is not the first UPF to the first UPF and sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS calls through the first UPF.

[0563] Step 2615: The SMF network element sends a QoS Flow establishment completion message for the first terminal to the P-CSCF network element through the PCF network element. The message carries the address information of the first UPF.

[0564] Step 2616: The SMF network element sends a QoS Flow establishment completion message for the second terminal to the P-CSCF network element through the PCF network element. This message carries the address information of the first UPF.

[0565] Step 2617: The P-CSCF network element sends a 183 message carrying the address information of the first UPF to the first terminal.

[0566] Step 2618: The P-CSCF network element sends a session update message to the second terminal, wherein the session update message includes the address information of the first UPF.

[0567] Step 2619: The first terminal and the second terminal complete the session establishment.

[0568] Step 2620: After the session is established, the first terminal and the second terminal can forward media plane data during the IMS call through the first UPF on the satellite.

[0569] It should be noted that for a detailed description of steps 2607 to 2620, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0570] Figure 27 This diagram illustrates the interaction process between the first terminal, the second terminal, the P-CSCF network element, the SMF network element, the PCF network element, and the first UPF on the satellite. Figure 4 .

[0571] like Figure 27 As shown, the method may include:

[0572] Step 2701: The first terminal sends a first session invitation request to the P-CSCF network element.

[0573] In one example, the first session invitation request carries the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, and the Session Description Protocol (SDP).

[0574] In another example, the first session invitation request carries the identification information of the second terminal, the IP address of the first terminal, the port number of the first terminal, the Session Description Protocol (SDP), and the location information of the first terminal.

[0575] Optionally, the first terminal can check whether it is connected to the satellite. If it finds that it is connected to the satellite, the first terminal can carry its location information in the first session invitation request sent to the P-CSCF network element.

[0576] The SDP contains the media address of the first terminal and the media types and encoding / decoding information supported by the first terminal.

[0577] SDP (Session Description Protocol) is primarily used for media negotiation before a session begins. The media address is the address used to send and receive media streams.

[0578] In this example, the location information of the first terminal may include at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, the access network type information corresponding to the first terminal, and the satellite identifier of the satellite to which the first terminal is connected.

[0579] Optionally, the identification information can be in the format of a Session Initiation Protocol Uniform Resource Identifier (SIP-URI) or a Telephone Uniform Resource Identifier (Tel-URI).

[0580] Optionally, SDP also includes the required bandwidth information, which the network side uses to determine the QoS bandwidth required for the dedicated load.

[0581] Step 2702: Send a first authentication and authorization request (AAR) message to the PCF network element. The first AAR message includes a first location query request, which is used to request the location information of the first terminal.

[0582] In this embodiment, after receiving the first session invitation request from the first terminal, regardless of whether the first session invitation request actively carries the location information of the first terminal, a first authentication authorization request (AAR) message can be sent to the PCF network element.

[0583] Step 2703: Receive a first Re-Authentication Request (RAR) message returned by the PCF network element in response to the first AAR message, wherein the first RAR message includes the location information of the first terminal.

[0584] Step 2704: The P-CSCF network element sends a second session invitation request to the second terminal.

[0585] The specific implementation method of the P-CSCF network element sending the second session invitation request to the second terminal can be found in the relevant descriptions in other embodiments, and will not be repeated here.

[0586] Step 2705: The P-CSCF network element receives the 183 message returned by the second terminal in response to the second session invitation request.

[0587] In one example, the second terminal may proactively carry its location information in a 183 message.

[0588] In another example, the second session invitation request includes a location information request message, which instructs the second terminal to provide its location information. Correspondingly, the first terminal carries the second terminal's location information in a 183 message based on this location information request message.

[0589] In this example, message 183 is the response message to the second session invitation request.

[0590] The 183 message may also include an SDP response message.

[0591] The SDP response message contains information about the media types and codecs supported by the called UE.

[0592] In this example, the location information of the second terminal may include at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, the access network type information corresponding to the second terminal, and the satellite identifier of the satellite to which the second terminal is connected.

[0593] Step 2706: Send a second AAR message to the PCF network element. The second AAR message includes a second location query request, which is used to request the location information of the second terminal.

[0594] In one embodiment of this disclosure, a response message returned by the second terminal in response to the second session invitation request can be received, and regardless of whether the response message returned by the second terminal carries the location information of the second terminal, a second AAR message can be sent to the PCF network element.

[0595] Step 2707: Receive the second RAR message returned by the PCF network element in response to the second AAR message, wherein the second RAR message includes the location information of the second terminal.

[0596] In this example, the location information of the second terminal may include, but is not limited to, at least one of the following: the cell identifier of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, the access network type information corresponding to the second terminal, and the satellite identifier of the satellite to which the second terminal is connected.

[0597] Step 2708: The P-CSCF network element checks whether the first terminal and the second terminal are connected to the same satellite based on the first terminal location information and the second terminal location information, and then executes steps 2709 and 2712.

[0598] In this example, the satellite is equipped with a first user plane function (UPF).

[0599] Step 2709: The P-CSCF network element sends a third AAR message to the PCF network element. The third AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The third AAR message includes an indication message, which indicates that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0600] Step 2710: The PCF network element sends a first request message to the SMF network element. The first request message is used to establish a Quality of Service (QoS) Flow for the first terminal to carry voice data during IMS voice calls. The first request message includes an indication message, which is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite.

[0601] Step 2711: The SMF network element initiates the establishment of the QoS Flow for the first terminal based on the first request message, and after learning from the indication information carried in the first request message that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, it checks whether the UPF corresponding to the IMSPUD session of the first terminal is the first UPF.

[0602] Step 2712: The P-CSCF network element sends a fourth AAR message to the PCF network element. The fourth AAR message is used to trigger the establishment of a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The fourth AAR message includes an indication message, which indicates that the second terminal meets the conditions for conducting IMS calls via satellite.

[0603] Step 2713: Send a second request message to the SMF network element through the PCF network element. The second request message is used to establish a Quality of Service (QoS) Flow for the second terminal to carry voice data during IMS voice calls. The second request message includes an indication message, which is used to indicate that the second terminal meets the conditions for conducting IMS calls via satellite.

[0604] Step 2714: The SMF network element initiates the establishment of the QoS Flow for the second terminal based on the second request message. After learning from the indication information carried in the second request message that the second terminal meets the conditions for IMS communication via satellite, it checks whether the UPF corresponding to the IMS PUD session of the second terminal is the first UPF.

[0605] Step 2715: When the SMF network element determines that the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal are the first UPF, it sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

[0606] Step 2716: If the SMF network element determines that at least one of the UPF corresponding to the IMS PUD session of the first terminal and the UPF corresponding to the IMS PUD session of the second terminal is not the first UPF, it modifies the UPF of the IMS PUD session whose UPF is not the first UPF to the first UPF and sends a notification message to the first UPF. The notification message is used to notify the first UPF that the first terminal and the second terminal will conduct IMS calls through the first UPF.

[0607] Step 2717: The SMF network element sends a QoS Flow establishment completion message for the first terminal to the P-CSCF network element through the PCF network element. The message carries the address information of the first UPF.

[0608] Step 2718: The SMF network element sends a QoS Flow establishment completion message for the second terminal to the P-CSCF network element through the PCF network element. This message carries the address information of the first UPF.

[0609] Step 2719: The P-CSCF network element sends a 183 message carrying the address information of the first UPF to the first terminal.

[0610] Step 2720: The P-CSCF network element sends a session update message to the second terminal, wherein the session update message includes the address information of the first UPF.

[0611] Step 2721: The first terminal and the second terminal complete the session establishment.

[0612] Step 2722: After the session is established, the first terminal and the second terminal can forward the media plane data during the IMS call through the first UPF on the satellite.

[0613] It should be noted that for a detailed description of steps 2709 to 2722, please refer to the relevant descriptions in other embodiments, which will not be repeated here.

[0614] To implement the above embodiments, this disclosure also proposes a communication device.

[0615] Figure 28 This is a block diagram illustrating a communication device for implementing a communication method according to an exemplary embodiment. It should be noted that the communication device 2800 in this embodiment can be used to implement the method described in the above method embodiments; for details, please refer to the descriptions in the above method embodiments.

[0616] like Figure 28 As shown, the communication device 2800 includes:

[0617] One or more processors 2801. Processor 2801 can be a general-purpose processor or a special-purpose processor, such as a baseband processor or a central processing unit (CPU). The baseband processor can be used to process communication protocols and communication data, while the CPU can be used to control communication devices (e.g., base stations, baseband chips, terminals, terminal chips, distributed units (DUs) or centralized units (CUs), execute programs, and process program data. Processor 2801 is used to invoke instructions to cause communication device 2800 to execute any of the above methods.

[0618] In some embodiments, the communication device 2800 further includes one or more memories 2802 for storing instructions. In some embodiments, all or part of the memories 2802 may also be located outside the communication device 2800.

[0619] In some embodiments, the communication device 2800 further includes one or more transceivers 2803. When the communication device 2800 includes one or more transceivers 2803, the communication steps such as sending and receiving in the above method are performed by the transceivers 2803, and other steps are performed by the processor 2801.

[0620] In some embodiments, transceiver 2803 may include a receiver and a transmitter, which may be separate or integrated together. In some embodiments, the terms transceiver, transceiver unit, transceiver, transceiver circuit, etc., may be used interchangeably; the terms transmitter, transmitting unit, transmitter, transmitting circuit, etc., may be used interchangeably; and the terms receiver, receiving unit, receiver, receiving circuit, etc., may be used interchangeably.

[0621] In some embodiments, the communication device 2800 further includes one or more interface circuits 2804 connected to the memory 2802. The interface circuits 2804 can be used to receive signals from the memory 2802 or other devices, and can be used to send signals to the memory 2802 or other devices. For example, the interface circuits 2804 can read instructions stored in the memory 2802 and send the instructions to the processor 2801.

[0622] The communication device 2800 described in the above embodiments may be a network device or a space terminal, but the scope of the communication device 2800 described in this disclosure is not limited thereto, and the structure of the communication device 2800 may vary. Figure 28 The limitations. Communication devices can be standalone devices or part of a larger device. For example, a communication device can be: (1) a standalone integrated circuit (IC), or chip, or chip system or subsystem; (2) a collection of one or more ICs, in some embodiments of which the collection of ICs may also include storage components for storing data and programs; (3) an ASIC, such as a modem; (4) a module that can be embedded in other devices; (5) a receiver, terminal, smart terminal, cellular phone, wireless device, handheld device, mobile unit, vehicle device, network device, cloud device, artificial intelligence device, etc.; (6) others, etc.

[0623] It should be noted that the implementation process and technical principles of the communication device in this embodiment are explained in the foregoing description of the communication method of this disclosure embodiment, and will not be repeated here.

[0624] Embodiments of this disclosure also propose a chip.

[0625] Figure 29 This is a schematic diagram of the structure of a chip according to an exemplary embodiment.

[0626] like Figure 29 As shown, the chip 2900 includes a processor 2901 and an interface circuit 2902. The number of processors 2901 and the number of interface circuits 2902 can be one or more.

[0627] Optionally, the chip also includes a memory 2903 for storing necessary computer programs and data; an interface circuit 2902 for receiving signals from the memory 2903 and sending signals to the processor 2901, the signals including computer instructions stored in the memory 2903, and when the processor 2901 executes the computer instructions, causing the communication device to perform the communication method described in the above embodiments of this disclosure.

[0628] To implement the above embodiments, this disclosure also proposes a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the communication method of the above embodiments.

[0629] To implement the above embodiments, this disclosure also provides a computer program product that executes the communication method of the above embodiments when the instruction processor in the computer program product is executed.

[0630] It should be noted that in the description of this disclosure, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0631] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of preferred embodiments of this disclosure includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this disclosure pertain.

[0632] It should be understood that various parts of this disclosure can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0633] Those skilled in the art will understand that all or part of the steps of the methods described in the above embodiments can be implemented by a program instructing related hardware, and the program can be stored in a computer-readable storage medium. When executed, the program includes one or a combination of the steps of the method embodiments.

[0634] Furthermore, the functional units in the various embodiments of this disclosure can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0635] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0636] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0637] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A communication method, characterized in that, The method is applied in the first network element, and the method includes: Receive a first session invitation request corresponding to the first terminal, wherein the first session invitation request is used to request a call with the second terminal via Internet Protocol Multimedia Subsystem (IMS); It is determined that the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first user plane function (UPF). A message is sent to the second network element to trigger the establishment of a QoS Flow for the second terminal, wherein the message triggering the establishment of a QoS Flow for the second terminal includes an indication message, the indication message being used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via the satellite.

2. The method as described in claim 1, characterized in that, The instruction message includes: the identification information of the first terminal and the second terminal.

3. The method as described in claim 1, characterized in that, Determining that the first terminal and the second terminal are connected to the same satellite includes: Based on the location information of the first terminal and the location information of the second terminal, it is determined that the first terminal and the second terminal are connected to the same satellite.

4. The method as described in claim 3, characterized in that, The first session invitation request includes the location information of the first terminal.

5. The method as described in claim 3, characterized in that, The first session invitation request includes the location information of the first terminal, and the method further includes: Send a second session invitation request to the second terminal, wherein the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal; Receive a response message returned by the second terminal, wherein the response message includes the location information of the second terminal.

6. The method as described in claim 3, characterized in that, The method includes: If the location information of the first terminal is not included in the first session invitation request, a location query request is sent to the second network element, wherein the location query request is used to request to query at least one of the location information of the first terminal and the location information of the second terminal; The system receives a location query response message returned by the second network element, wherein the location query response message includes at least one of the location information of the first terminal and the location information of the second terminal.

7. The method as described in claim 3, characterized in that, The method includes: Send a second location query request to the second network element. The second location query request is used to request the location information of the second terminal. The system receives a second location query response message returned by the second network element, wherein the second location query response message includes the location information of the second terminal.

8. The method as described in claim 3, characterized in that, The location information of the first terminal includes at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, the access network type information corresponding to the first terminal, and the satellite identifier of the satellite to which the first terminal is connected. The location information of the second terminal includes at least one of the following: the cell identifier information of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, the access network type information corresponding to the second terminal, and the satellite identifier of the satellite to which the second terminal is connected.

9. The method as described in claim 1, characterized in that, The message that triggers the establishment of the QoS Flow for the second terminal also includes the call mode of the IMS call, wherein the call mode is either an IMS voice call or an IMS video call.

10. The method as described in claim 1, characterized in that, The method further includes: The system receives a second QoS Flow establishment completion message sent by the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF; The address information of the first UPF is sent to the second terminal.

11. A communication method, characterized in that, The method is applied in the second network element, and the method includes: The system receives an indication message sent by a first network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, wherein the satellite includes a first user plane function (UPF), and the indication message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite. Send the instruction message to the third network element.

12. The method as described in claim 11, characterized in that, A message requesting the establishment of a QoS Flow for the second terminal is sent to the third network element, wherein the message requesting the establishment of a QoS Flow for the second terminal includes the indication message.

13. The method of claim 12, wherein the message requesting the establishment of a QoS Flow for the second terminal further includes the call mode of the IMS call, wherein, The call method is either IMS voice call or IMS video call.

14. The method according to any one of claims 11-13, characterized in that, The instruction message includes the identification information of the first terminal and the second terminal.

15. The method as described in claim 14, characterized in that, The method further includes: The system receives a location query request sent by the first network element, wherein the location query request is used to query at least one of the location information of the first terminal and the location information of the second terminal. A location query response message is sent to the first network element, wherein the location query response message includes at least one of the location information of the first terminal and the location information of the second terminal.

16. The method as described in claim 12, characterized in that, The method further includes: The system receives a second QoS Flow establishment completion message sent by the third network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF; The message indicating that the second QoS Flow has been established is sent to the first network element.

17. The method as described in claim 15, characterized in that, The location information of the first terminal and the location information of the second terminal are used by the first network element to determine whether the first terminal and the second terminal are connected to the same satellite.

18. A communication method, characterized in that, The method is applied in a third network element, and the method includes: The system receives an indication message sent by a second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, the first terminal and the second terminal are connected to the same satellite, and the satellite includes a first user plane function (UPF). A notification message is sent to the first UPF, wherein the notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

19. The method as described in claim 18, characterized in that, The method further includes: If at least one of the UPF corresponding to the IMS PDU session of the first terminal and the UPF corresponding to the IMS PDU session of the second terminal is not the first UPF, the UPF of the IMS PDU session whose UPF is not the first UPF shall be modified to the first UPF.

20. The method as described in claim 18 or 19, characterized in that, The system receives a message from a second network element requesting the establishment of a Quality of Service (QoS) Flow for the second terminal, wherein the message requesting the establishment of a QoS Flow for the second terminal includes the indication message.

21. The method as described in claim 18 or 19, characterized in that, Both the notification message and the instruction message include the identification information of the first terminal and the second terminal.

22. The method as described in claim 20, characterized in that, The method further includes: A second QoS Flow establishment completion message is sent to the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF.

23. A communication device, characterized in that, The device is used in the first network element, and the device includes: The receiving module is used to receive a first session invitation request corresponding to the first terminal, wherein the first session invitation request is used to request a call with the second terminal via Internet Protocol Multimedia Subsystem (IMS). A determination module is used to determine that the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first user plane function (UPF). The sending module is used to send a message to the second network element to trigger the establishment of a QoS Flow for the second terminal, wherein the message triggering the establishment of a QoS Flow for the second terminal includes an indication message, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls through the satellite.

24. The apparatus as claimed in claim 23, characterized in that, The instruction message includes: the identification information of the first terminal and the second terminal.

25. The apparatus as claimed in claim 23, characterized in that, The determining module is further configured to determine, based on the location information of the first terminal and the location information of the second terminal, that the first terminal and the second terminal are connected to the same satellite.

26. The apparatus as claimed in claim 25, characterized in that, The first session invitation request includes the location information of the first terminal.

27. The apparatus as claimed in claim 25, characterized in that, The first session invitation request includes the location information of the first terminal. The sending module is further configured to send a second session invitation request to the second terminal, wherein the second session invitation request includes a location information request message, wherein the location information request message is used to instruct the second terminal to provide the location information of the second terminal. The receiving module is further configured to receive a response message returned by the second terminal, wherein the response message includes the location information of the second terminal.

28. The apparatus as claimed in claim 25, characterized in that, The device further includes: The first processing module is configured to send a location query request to the second network element when the location information of the first terminal is not included in the first session invitation request, wherein the location query request is used to request to query at least one of the location information of the first terminal and the location information of the second terminal; The system receives a location query response message returned by the second network element, wherein the location query response message includes at least one of the location information of the first terminal and the location information of the second terminal.

29. The apparatus as claimed in claim 25, characterized in that, The device further includes: The second processing module is used to send a second location query request to the second network element, wherein the second location query request is used to request the location information of the second terminal; The system receives a second location query response message returned by the second network element, wherein the second location query response message includes the location information of the second terminal.

30. The apparatus as claimed in claim 25, characterized in that, The location information of the first terminal includes at least one of the following: the cell identifier information of the cell where the first terminal is located, the base station identifier of the base station to which the first terminal is connected, the access network type information corresponding to the first terminal, and the satellite identifier of the satellite to which the first terminal is connected. The location information of the second terminal includes at least one of the following: the cell identifier information of the cell where the second terminal is located, the base station identifier of the base station to which the second terminal is connected, the access network type information corresponding to the second terminal, and the satellite identifier of the satellite to which the second terminal is connected.

31. The apparatus as claimed in claim 23, characterized in that, The message that triggers the establishment of the QoS Flow for the second terminal also includes the call mode of the IMS call, wherein the call mode is either an IMS voice call or an IMS video call.

32. The apparatus as claimed in claim 23, characterized in that, The receiving module is further configured to receive a second QoS Flow establishment completion message sent by the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF; The sending module is also used to send the address information of the first UPF to the second terminal.

33. A communication device, characterized in that, The device is used in the second network element, and the device includes: A receiving module is used to receive an indication message sent by a first network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, wherein the satellite includes a first user plane function (UPF), and the indication message is sent by the first network element after determining that the first terminal and the second terminal are connected to the same satellite; The sending module is used to send the indication message to the third network element.

34. The apparatus as claimed in claim 33, characterized in that, A message requesting the establishment of a QoS Flow for the second terminal is sent to the third network element, wherein the message requesting the establishment of a QoS Flow for the second terminal includes the indication message.

35. The apparatus of claim 34, wherein the message requesting the establishment of a QoS Flow for the second terminal further includes the call mode of the IMS call, wherein, The call method is either IMS voice call or IMS video call.

36. The apparatus as claimed in any one of claims 33-35, characterized in that, The instruction message includes the identification information of the first terminal and the second terminal.

37. The apparatus as claimed in claim 36, characterized in that, The receiving module is further configured to receive a location query request sent by the first network element, wherein the location query request is used to query at least one of the location information of the first terminal and the location information of the second terminal; The sending module is further configured to send a location query response message to the first network element, wherein the location query response message includes at least one of the location information of the first terminal and the location information of the second terminal.

38. The apparatus as claimed in claim 34, characterized in that, The receiving module is further configured to receive a second QoS Flow establishment completion message sent by the third network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF; The sending module is further configured to send the second QoS Flow establishment completion message to the first network element.

39. The apparatus as claimed in claim 37, characterized in that, The location information of the first terminal and the location information of the second terminal are used by the first network element to determine whether the first terminal and the second terminal are connected to the same satellite.

40. A communication device, characterized in that, The device is used in a third network element, and the device includes: A receiving module is used to receive an indication message sent by a second network element, wherein the indication message is used to indicate that the first terminal and the second terminal meet the conditions for conducting IMS calls via satellite, the first terminal and the second terminal are connected to the same satellite, wherein the satellite includes a first user plane function (UPF); The sending module is used to send a notification message to the first UPF, wherein the notification message is used to notify the first UPF that the first terminal and the second terminal will conduct an IMS call through the first UPF.

41. The apparatus as claimed in claim 40, characterized in that, The device further includes: The modification module is used to modify the UPF of the IMS PDU session whose UPF is not the first UPF to the first UPF when at least one of the UPF corresponding to the IMS PDU session of the first terminal and the UPF corresponding to the IMS PDU session of the second terminal is not the first UPF.

42. The apparatus as claimed in claim 40 or 41, characterized in that, The system receives a message from a second network element requesting the establishment of a Quality of Service (QoS) Flow for the second terminal, wherein the message requesting the establishment of a QoS Flow for the second terminal includes the indication message.

43. The apparatus as claimed in claim 40 or 41, characterized in that, Both the notification message and the instruction message include the identification information of the first terminal and the second terminal.

44. The apparatus as claimed in claim 42, characterized in that, The sending module is further configured to send a second QoS Flow establishment completion message to the second network element, wherein the second QoS Flow establishment completion message indicates that the QoS Flow of the second terminal has been established, and the second QoS Flow establishment completion message includes the address information of the first UPF.

45. A communication device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, when the processor executes the computer program, it implements the method as described in any one of claims 1-10, or the method as described in any one of claims 11-17, or the method as described in any one of claims 18-22.

46. ​​A communication system, characterized in that, It includes the first network element, the second network element, and the third network element, among which: The first network element is used to implement the method according to any one of claims 1-10; The second network element is used to implement the method according to any one of claims 11-17; The third network element is used to implement the method of any one of claims 18-22.

47. A chip, characterized in that, The device includes one or more interface circuits and one or more processors; the interface circuits are configured to receive signals from the memory of the communication device and send the received signals to the processors, the received signals including computer instructions stored in the memory, which, when executed by the processors, cause the communication device to implement the method of any one of claims 1-10, or the method of any one of claims 11-17, or the method of any one of claims 18-22.

48. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method described in any one of claims 1-10, or the method described in any one of claims 11-17, or the method described in any one of claims 18-22.

49. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method of any one of claims 1-10, or the method of any one of claims 11-17, or the method of any one of claims 18-22.

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