WO2019071877A1 - Voice switching method and related device - Google Patents

Abstract

Disclosed in the embodiments of the present application are a voice switching method and a related device, for simplifying a voice conversation switching process of a user device, reducing a switching delay, improving a switching success rate, ensuring continuity of the voice conversation. The method according to the embodiments of the present application comprises: a first functional entity receiving a first request sent by a second functional entity, the first request comprising bearing information and an identifier of a target access network node; the first functional entity acquiring voice bearing information according to the bearing information; the first functional entity sending a second request to a target mobile switching center (MSC), the target MSC serving the target access network node, the target MSC being a device in a target communication system, and the second request being used to request to switch the voice conversation corresponding to the voice bearing information from the first communication system to the target communication system.

Description

Voice switching method and related device

The present application claims priority to Chinese Patent Application No. JP-A No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. in.

Technical field

The present application relates to the field of communications, and in particular, to a method for voice switching and related devices.

Background technique

Currently, mobile communication systems are evolving to fifth generation mobile communication (5Gration, 5G) systems, which will also support voice sessions. Due to the movement of the user equipment (terminal) or the change of the network signal, the user equipment may need to transfer the ongoing voice session from the 5G system to other mobile communication network systems, such as the third generation mobile communication (3Generation, 3G) system/ Second generation mobile communication (2Generation, 2G) system.

Currently, 5G systems do not support direct switching to 3G/2G systems. If the 5G system is enhanced to support direct switching to the 3G/2G system, the device interface between the 5G system and the 3G/2G system needs to be increased, which increases the complexity of the 5G system.

When a voice session needs to be switched from a 5G system to a 3G/2G system, two handover procedures are required, so the handover delay is long; and when the 5G system's radio access network (RAN) cannot find a suitable one. When the 4G evolved base station (eNB) is used as the handover target base station, the voice switching process cannot be performed, resulting in interruption of the voice session.

Summary of the invention

The embodiment of the present invention provides a voice switching method and related device, which is used to simplify the process of voice session switching of a user equipment, reduce handover delay, improve handover success rate, and ensure continuity of voice conversation.

The first aspect of the present application provides a method for voice switching, including: a first function entity receives a first request sent by a second function entity, where the first request carries bearer information and an identifier of a target access network node, The first request is for requesting to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication system, wherein the second functional entity is a device in the first communication system, the first The function entity is a device in the second communication system; the first function entity acquires voice bearer information according to the bearer information carried in the first request; the first function entity sends a second request to the target mobile switching center MSC, The target MSC serves the target access network node, the target MSC is a device in a target communication system, and the second request is for requesting to switch the voice session from the first communication system to the a target communication system, the voice session corresponding to the voice bearer information. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible implementation, in a first implementation manner of the first aspect of the embodiments, the first functional entity sends a second request to the target mobile switching center MSC, where: the first functional entity is configured according to The identifier of the target access network node determines the target MSC; the first functional entity sends a second request to the target MSC, so that the target MSC reserves a handover resource for the voice session. The process of sending the second request is refined, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the first aspect of the embodiments, the first request further includes a voice switching indication, where the first functional entity sends a message to the target mobile switching center MSC. The second request includes: the first functional entity determining the target MSC according to the voice switching indication; the first functional entity sending a second request to the target MSC, so that the MSC is pre-for the voice session The switching resource is reserved, and the second request carries the voice switching indication. When the voice request indication is included in the first request, the process of transmitting the second request is refined, so that the application is more complete in the steps.

In a possible design, in a third implementation manner of the first aspect of the embodiments, the method further includes: the first functional entity acquiring a single radio frequency session transfer number STN according to the first request. SR and mobile station international subscriber identity MSISDN; the first functional entity determines the target MSC based on the STN-SR and the MSISDN. It is clarified that the first request carries the STN-SR and the MSISDN, which increases the achievable manner of the embodiment.

In a possible design, in a fourth implementation manner of the first aspect of the embodiments, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolution. Radio access network GERAN identity.

In a possible implementation, in a fifth implementation manner of the first aspect of the embodiments, the voice switching indication is further used to indicate that the packet switched PS network is switched while performing the single radio frequency voice call continuity RVCC. The method further includes: the first functional entity transmitting a third request to a target general packet radio service support node SGSN, the second request for instructing the target SGSN to switch a non-voice bearer to the target communication system PS network. The processing procedure for the non-voice bearer is added, so that the embodiment is more perfect in the steps.

In a possible design, in a sixth implementation manner of the first aspect of the embodiments of the present application, the second universal communication system does not have a switched evolved universal terrestrial radio access network E-UTRAN cell, There is a switched universal terrestrial radio access network UTRAN/global mobile communication system and an evolved radio access network GERAN cell in the target communication system.

A second aspect of the present application provides a method for voice switching, including: receiving, by a first function entity, a first request sent by a radio access network device, where the first request includes an identifier of a target access network node, where the a request for requesting to switch a voice session in progress of the user equipment UE from the first communication system to the target communication system, the first functional entity being a device in the first communication system, the wireless access network device being a device of the first communication system; the first function entity determines a second function entity of the session management function entity corresponding to the voice session, and acquires voice bearer information of the voice session from the second function entity, The second functional entity is a device of the first communication system; the first functional entity sends a second request to the third functional entity, where the second request includes the voice bearer information and the target access network node The identifier of the third functional entity is a device in the second communication system. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible implementation, in a first implementation manner of the second aspect of the embodiment, the second request is used to request the third functional entity to send a third request to the target mobile switching center MSC. The target MSC serves the target access network node, and the third request is used to request to switch the voice session from the first communication system to the target communication system, where the target MSC is in the target communication system. device of. The second request is defined, and the function of the second request is clarified, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the second aspect of the embodiments, the first request further includes session identifier information, where the session identifier information includes a session identifier of the voice session, where Determining, by the first functional entity, the second functional entity corresponding to the voice session, the first functional entity determining a session identifier of the voice session according to the session identifier information, and determining, according to the session identifier of the voice session, The second functional entity. The process of determining the second functional entity is refined, and the implementation of the embodiment is added.

In a possible design, in a third implementation manner of the second aspect of the embodiments of the present application, the first functional entity determines a second functional entity corresponding to the voice session, including: the first functional entity A second functional entity having voice conferencing support capability is determined from at least two second functional entities corresponding to all sessions of the UE. The process of determining the second functional entity is refined, and the implementation of the embodiment is added.

In a possible implementation, in a fourth implementation manner of the second aspect of the embodiments, the first request further includes session identification information, and the first functional entity determines a second corresponding to the voice session. a functional entity, comprising: the first functional entity determining network slice selection assistance information NSSAI and/or a data network name DNN according to the session identification information carried in the first request; the first functional entity according to the NSSAI And/or the DNN, determining that the second functional entity corresponding to the NSSAI and/or the DNN has the support voice session capability; the first functional entity determines the second functional entity. The process of determining the second functional entity according to the NSSAI is refined, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a fifth implementation manner of the second aspect of the embodiments, the first request further includes session identifier information, where the session identifier information includes a session identifier of the voice session, where Acquiring the voice bearer information of the voice session from the second function entity, the method includes: the first function entity sends a fourth request to the second function entity, where the fourth request carries the voice session a session identifier; the first function entity receives the voice bearer information corresponding to the session identifier of the voice session sent by the second function entity. The specific process of obtaining the voice bearer is refined, and the embodiment is more perfect in the steps.

In a possible implementation, in a sixth implementation manner of the second aspect of the embodiments, the first request further includes a voice switching indication, where the acquiring the voice session from the second function entity The voice bearer information includes: the first function entity sends a fifth request to the second function entity, where the fifth request carries the voice switch indication; and the first function entity receives the second function The entity carries the voice bearer information according to the voice switching indication. The specific process of obtaining the voice bearer is refined, and the embodiment is more perfect in the steps.

In a possible design, in a seventh implementation manner of the second aspect, the first functional entity sends a second request to the third functional entity, where the first functional entity obtains the single a radio frequency session transfer number STN-SR and a mobile station international subscriber identity (MSISDN); the first functional entity sends the second request to the third functional entity, where the second request carries the STN-SR and the Said MSISDN. It is clarified that the first request carries the STN-SR and the MSISDN, which increases the achievable manner of the embodiment.

In a possible design, in an eighth implementation manner of the second aspect of the embodiments of the present application, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolution. Radio access network GERAN identity.

In a possible design, in a ninth implementation manner of the second aspect of the embodiments, the method further includes: determining, by the first functional entity, the identifier according to the identifier of the preset third functional entity a third functional entity; or the first functional entity queries the domain name system DNS and/or the network storage function function entity NRF to obtain the identifier of the third functional entity; the first functional entity is based on the identifier of the third functional entity Determining the third functional entity. The process of specifically determining the third functional entity is refined, and the implementation of the embodiment is increased.

In a possible design, in a tenth implementation manner of the second aspect of the embodiments of the present application, the second universal communication system does not have a switched evolved universal terrestrial radio access network E-UTRAN cell, There is a switched universal terrestrial radio access network UTRAN/global mobile communication system and an evolved radio access network GERAN cell in the target communication system.

A third aspect of the present application provides a method for voice switching, including: a radio access network device receiving a measurement report sent by a user equipment, where the radio access network device is a device of a first communication system; The measurement report sends a first request to the first functional entity, the first request for requesting to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication system, the first functional entity The device in the first communication system; the first request carries the session identifier information, where the session identifier information includes only the session identifier of the voice session, or the session identifier information includes a voice indication Session ID. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible implementation, in a first implementation manner of the third aspect of the embodiments, the first request is used to request the first functional entity to determine a second functional entity according to the session identifier, The second functional entity acquires voice bearer information of the voice session, and then switches the voice session from the first communication system to the target communication system by using a third functional entity, where the second functional entity is The device in the first communication system, the third functional entity is a device in the second communication system. The first request is defined, the function of the second request is clarified, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the third aspect of the embodiments of the present application, the method further includes: the access network device is configured to perform radio bearer according to at least the voice stream information or the voice data of the UE. Information, and the measurement report, determining to switch the voice session from the first communication system to the target communication system. The process of triggering voice session switching is added, which makes the embodiment of the present application more logical.

In a possible design, in a third implementation manner of the third aspect of the embodiments of the present application, the method further includes: the access network device at least according to the voice stream information or the voice data radio bearer of the UE Information determining a session identifier of the voice session. The process of determining the session identifier of the voice session is added, so that the embodiment of the present application is more complete in steps.

In a possible design, in a fourth implementation manner of the third aspect of the embodiments of the present application, the first request is used to request to switch the voice session from the first communications system to the target communications. The circuit switched domain of the system.

The fourth aspect of the present application provides a functional entity, where the functional entity is a first functional entity, and includes: a receiving unit, configured to receive a first request sent by a second functional entity, where the first request includes bearer information and An identifier of the target access network node, the first request is used to request that the ongoing voice session of the user equipment UE is switched from the first communication system to the target communication system, and the second functional entity is in the first communication system The first function entity is a device in the second communication system; the first acquiring unit is configured to obtain voice bearer information according to the bearer information; and the first sending unit is configured to send the first message to the target mobile switching center MSC. The second request, the target MSC serves the target access network node, the target MSC is a device in the target communication system, and the second request is used to request the voice session corresponding to the voice bearer information The first communication system switches to the target communication system. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible design, in a first implementation manner of the fourth aspect of the embodiments of the present application, the first sending unit is specifically configured to: determine the target MSC according to the identifier of the target access network node; Sending a second request to the target MSC to cause the target MSC to reserve a handover resource for the voice session. The process of sending the second request is refined, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the fourth aspect of the embodiments of the present application, the first request further includes a voice switching indication, where the first sending unit is further configured to: The voice switching indication determines the target MSC; sends a second request to the target MSC, so that the target MSC reserves a handover resource for the voice session, and the second request carries the voice handover indication. When the voice request indication is included in the first request, the process of transmitting the second request is refined, so that the application is more complete in the steps.

In a possible design, in a third implementation manner of the fourth aspect of the embodiments of the present application, the first functional entity further includes: a second obtaining unit, configured to acquire a single radio frequency session transfer number according to the first request The STN-SR and the mobile station international subscriber identity (MSISDN) determining unit is configured to determine the target MSC according to the STN-SR and the MSISDN. It is clarified that the first request carries the STN-SR and the MSISDN, which increases the achievable manner of the embodiment.

In a possible design, in a fourth implementation manner of the fourth aspect of the embodiments of the present application, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolution. Radio access network GERAN identity.

In a possible implementation, in a fifth implementation manner of the fourth aspect of the embodiments of the present application, the voice switching indication is further used to indicate that the packet switched PS network is switched while performing the single radio frequency voice call continuity RVCC, The first functional entity further includes: a second sending unit, configured to send a third request to the target general packet radio service support node SGSN, where the second request is used to instruct the target SGSN to switch the non-voice bearer to the The PS network of the target communication system. The processing procedure for the non-voice bearer is added, so that the embodiment is more perfect in the steps.

In a possible design, in a sixth implementation manner of the fourth aspect of the embodiments of the present application, the second universal communication system does not have a switched evolved universal terrestrial radio access network E-UTRAN cell, There is a switched universal terrestrial radio access network UTRAN/global mobile communication system and an evolved radio access network GERAN cell in the target communication system.

The fifth aspect of the present application provides a functional entity, where the functional entity is a first functional entity, and includes: a receiving unit, configured to receive a first request sent by a radio access network device, where the first request includes a target connection An identifier of the network access node, the first request is used to request to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication system, where the first functional entity is a device in the first communication system The radio access network device is a device of the first communication system, and the processing unit is configured to determine a second functional entity corresponding to the voice session, and obtain a voice bearer of the voice session from the second functional entity. Information, the second function entity is a device of the first communication system, and a sending unit is configured to send a second request to the third function entity, where the second request includes the voice bearer information and the target connection The identifier of the network access node, where the third functional entity is a device in the second communication system. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible implementation, in a first implementation manner of the fifth aspect of the embodiments, the second request is used to request the third functional entity to send a third request to the target mobile switching center MSC. The target MSC serves the target access network node, and the third request is used to request to switch the voice session from the first communication system to the target communication system, where the target MSC is in the target communication system. device of. The second request is defined, and the function of the second request is clarified, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the fifth aspect of the embodiments, the first request further includes session identifier information, where the session identifier information includes a session identifier of the voice session, where The processing unit is specifically configured to: determine a session identifier of the voice session according to the session identifier information, and determine the second function entity according to the session identifier of the voice session. The process of determining the second functional entity is refined, and the implementation of the embodiment is added.

In a possible design, in a third implementation manner of the fifth aspect of the embodiments of the present application, the processing unit is specifically configured to: determine, from at least two second functional entities corresponding to all sessions of the UE A second functional entity with voice session support capabilities. The process of determining the second functional entity is refined, and the implementation of the embodiment is added.

In a possible design, in a fourth implementation manner of the fifth aspect of the embodiments, the first request further includes session identifier information, where the processing unit is specifically configured to: according to the first request Carrying the session identification information to determine network slice selection assistance information NSSAI and/or data network name DNN; determining, according to the NSSAI and/or the DNN, the second function corresponding to the NSSAI and/or the DNN The entity has the voice support session capability; the second functional entity is determined. The process of determining the second functional entity according to the NSSAI and/or the DNN is refined, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a fifth implementation manner of the fifth aspect of the embodiments, the first request further includes session identifier information, where the session identifier information includes at least one voice session identifier, and the processing The unit is further configured to: send a fourth request to the second function entity, where the fourth request carries a session identifier of the voice session; and receive a session identifier corresponding to the voice session sent by the second function entity. The voice carries information. The specific process of obtaining the voice bearer is refined, and the embodiment is more perfect in the steps.

In a possible design, in a sixth implementation manner of the fifth aspect of the embodiments, the first request further includes a voice switching indication, where the processing unit is further configured to: The function entity sends a fifth request, where the fifth request carries the voice switching indication; and receives the voice bearer information sent by the second function entity according to the voice switching indication. The specific process of obtaining the voice bearer is refined, and the embodiment is more perfect in the steps.

In a possible design, in a seventh implementation manner of the fifth aspect of the embodiment, the sending unit is specifically configured to: acquire a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN; Sending the second request to the third functional entity, where the second request carries the STN-SR and the MSISDN. It is clear that the first request carries the STN-SR and the MSISDN, which increases the achievable manner of the embodiment.

In a possible design, in an eighth implementation manner of the fifth aspect of the embodiments of the present application, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolution. Radio access network GERAN identity.

In a possible design, in a ninth implementation manner of the fifth aspect of the embodiments, the first functional entity further includes: a determining unit, configured to determine, according to the identifier of the preset third functional entity, The third functional entity; or the domain name system DNS and/or the network storage function function entity NRF obtains the identifier of the third functional entity; and the third functional entity is determined according to the identifier of the third functional entity. The process of specifically determining the third functional entity is refined, and the implementation of the embodiment is increased.

In a possible design, in a tenth implementation manner of the fifth aspect of the embodiments of the present application, the second universal communication system does not have a switched evolved universal terrestrial radio access network E-UTRAN cell, There is a switched universal terrestrial radio access network UTRAN/global mobile communication system and an evolved radio access network GERAN cell in the target communication system.

The sixth aspect of the present application provides a radio access network device, including: a receiving unit, configured to receive a measurement report sent by a user equipment, where the radio access network device is a device of the first communication system, and a sending unit, configured to The measurement report sends a first request to the first functional entity, the first request is used to request to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication system, where the first functional entity is The device in the first communication system; the first request carries the session identifier information, where the session identifier information includes only the session identifier of the voice session, or the session identifier information includes the voice indication Session ID. In the embodiment of the present application, the voice session of the UE in the first communication system is switched to the target communication system via the second communication system core network device, and the access network of the second communication system is not required to participate in the handover, thereby reducing the handover delay. And improve the success rate of the handover and maintain the continuity of the voice session.

In a possible implementation, in a first implementation manner of the sixth aspect of the embodiments of the present application, the first request is used to request the first functional entity to determine a second functional entity according to the session identifier, The second functional entity acquires voice bearer information of the voice session, and then switches the voice session from the first communication system to the target communication system by using a third functional entity, where the second functional entity is The device in the first communication system, the third functional entity is a device in the second communication system. The first request is defined, the function of the second request is clarified, and the implementation manner of the embodiment of the present application is added.

In a possible implementation, in a second implementation manner of the sixth aspect of the embodiments, the radio access network device further includes: a first determining unit, configured to use, according to at least the voice stream information of the UE Or voice data radio bearer information, and the measurement report, determining to switch the voice session from the first communication system to the target communication system. The process of triggering voice session switching is added, which makes the embodiment of the present application more logical.

In a possible design, in a third implementation manner of the sixth aspect of the embodiments, the radio access network device further includes: a second determining unit, configured to: at least according to the voice stream information of the UE Or voice data radio bearer information, determining a session identifier of the voice session. The process of determining the session identifier of the voice session is added, so that the embodiment of the present application is more complete in steps.

In a possible implementation, in the four implementation manners of the sixth aspect of the embodiments of the present application, the first request is used to request to switch the voice session from the first communication system to the target communication system. Circuit switched domain.

A seventh aspect of the present application provides a computer readable storage medium having stored therein instructions that, when executed on a computer, cause the computer to perform the method of any of the above aspects .

An eighth aspect of the present application provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of any of the above aspects.

DRAWINGS

1 is a schematic diagram of a conventional voice switching process;

2 is a schematic diagram of a network architecture applied to an embodiment of the present application;

3 is a schematic diagram of an embodiment of a method for voice switching in an embodiment of the present application;

4 is a schematic diagram of another embodiment of a method for voice switching in an embodiment of the present application;

FIG. 5 is a schematic diagram of another embodiment of a method for voice switching according to an embodiment of the present application;

FIG. 6 is a schematic diagram of another embodiment of a method for voice switching according to an embodiment of the present application;

FIG. 7 is a schematic diagram of an embodiment of a mobility management entity according to an embodiment of the present application;

FIG. 8 is a schematic diagram of an embodiment of an access and mobility management function entity in an embodiment of the present application;

FIG. 9 is a schematic diagram of an embodiment of a radio access network device according to an embodiment of the present application;

FIG. 10 is a schematic diagram of another embodiment of a mobility management entity according to an embodiment of the present application;

11A is a schematic diagram of another embodiment of an access and mobility management function entity in an embodiment of the present application;

11B is a schematic diagram of another embodiment of an access and mobility management function entity in an embodiment of the present application;

FIG. 12 is a schematic diagram of another embodiment of a radio access network device according to an embodiment of the present application.

Detailed ways

The embodiment of the present application provides a method and a device for voice switching, which are used to simplify the process of voice session switching of a user equipment, and the 5G system switches to the 3G/2G system via the 4G core network, and does not require the 4G access network to participate in the handover. Thereby reducing the handover delay, and improving the handover success rate, maintaining the continuity of the voice session.

The embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention.

The terms "first", "second", "third", "fourth", etc. (if present) in the specification and claims of the present invention and the above figures are used to distinguish similar objects without having to use To describe a specific order or order. It is to be understood that the data so used may be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than what is illustrated or described herein. In addition, the term "comprises" or "comprises" or any variations thereof, is intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those that are clearly listed Steps or units, but may include other steps or units not explicitly listed or inherent to such processes, methods, products or devices.

As shown in Figure 1, when a voice session needs to be switched from a 5G system to a 3G/2G system, if the voice session is first switched from a 5G system to an evolved packet system (EPS), then a single radio voice call is made. The single radio voice call continuity (SRVCC) handover scheme switches the voice session from EPS to 3G/2G system; then: since this process involves two handover procedures (switching from 5G system to EPS system, then EPS system) Switching to the 3G/2G system), so the handover delay is longer; and when the 5G system's radio access network (RAN) cannot find a suitable 4G evolved Node B (eNB) as the handover target base station The above process will not be performed, causing the voice session to be interrupted.

The embodiment of the present application can be applied to the network architecture shown in FIG. 2, in which the voice session of the user equipment (UE) is switched from the 5G system to the 3G/2G system through the 4G core network. The 4G access network participates in the handover, which reduces the network elements that need to be used in the handover process, shortens the switching path from the 5G system to the 3G/2G system, reduces the handover delay, and improves the handover success rate. The first communication system involved in the embodiment of the present application is a 5G system, the second communication system is a 4G system, and the target communication system is a 3G/2G system, wherein the access network of the 4G system may be an evolved universal terrestrial radio access network. (evolved universal terrestrial radio access network, E-UTRAN), the access network of the 3G system may be a universal terrestrial radio access network (UTRAN), and the access network of the 2G system may be a global mobile communication system ( Global system for mobile communications (GSM)/enhanced data rate for GSM evolution (EDGE) GSM radio access network (GERAN). For convenience of description, in the embodiment of the present application and the subsequent embodiments, the 5G system is switched to the 3G system through the 4G system as an example for description.

For the convenience of description, the specific process of the embodiment of the present application is described below. Referring to FIG. 3, in this embodiment, the first functional entity is a mobility management entity (MME), and the second functional entity is access. And a mobility management function entity (AMF), the third function entity is a session management function entity SMF, and the voice switching method in the embodiment of the present application is in the scenario that the voice bearer and the non-voice bearer are separated by the MME. One embodiment of the method includes:

301. The UE sends a measurement report to the 5G RAN.

The user equipment UE sends a measurement report to the access network device (5G RAN) of the 5G system.

It should be noted that the UE accesses the 5G serving cell in the 5G system, and before transmitting the measurement report, the user equipment continuously detects the signal quality of the currently accessed 5G serving cell and generates a measurement report. The UE sends the generated measurement report to the radio access network device in the 5G system according to the preset time interval. The measurement report includes measurement results of signal energy and/or signal quality of the accessed 5G serving cell, and measurement of signal energy and/or signal quality of neighboring cells of other standards (eg, E-UTRAN, UTRAN, GERAN). result.

302, 5G RAN decides to perform network switching.

The 5G RAN decides to perform network switching based on the received measurement report.

Specifically, the 5G access network device is based on the measurement report reported by the UE, and the quality of service (QoS) flow of the voice session exists in the protocol data unit (PDU) session being performed by the UE. The 5G access network device determines to trigger a single radio voice call continuity (SRVCC) handover to a universal terrestrial radio access network (UTRAN). A 5G access network device (e.g., gNB) selects a UTRAN device (e.g., a radio network subsystem (RNS)/base station subsystem (BSS)) as the target access network device.

It should be noted that, if according to the measurement report of the UE, it is determined whether there is an E-UTRAN cell for handover; if there is an E-UTRAN cell for handover, the 5G access network device initiates a voice session handover to the E-UTRAN, and the voice session Switching to the E-UTRAN network continues; if there is no E-UTRAN cell for handover, it continues to determine whether there is a UTRAN cell for handover; if there is a UTRAN cell for handover, the 5G access network device initiates SRVCC handover, the UE The voice session will be switched from the 5G system to the UTRAN circuit switch (CS) network.

303. The 5G RAN sends a handover request message to the access and mobility management function entity AMF.

The 5G access network device sends a handover request message to the access and mobility management function (AMF).

Specifically, the 5G access network device sends a handover request message (ie, a Handover Required) to the AMF, where the handover request message carries the bearer information, the identifier of the target access network node, and the voice handover indication (ie, the SRVCC handover indication), and the target access The network node is an access network device in the 3G network, and the identifier of the target access network node may be a UTRAN network device identifier or a GERAN network device identifier. In the embodiment of the present application and subsequent embodiments, the UTRAN network device identifier is used as the target access. The network node is described. The handover request message may also not carry the voice handover indication, and the voice handover indication is generated by the AMF, and details are not described herein again.

It should be noted that the handover request message also carries the identifier of all PDU sessions (ie, PDU session ID(s)) of the UE on the 5G access network device, and the handover request message may also carry a common source to target. Parameters such as a transparent container (Generic Source to Target Transparent Container).

It can be understood that the SRVCC handover indication (HO Indication) is used to indicate that this is an SRVCC handover. Further, the SRVCC HO Indication may indicate that packet switching (PS) handover is performed while performing the SRVCC handover, or PS switching is not performed while SRVCC is being executed.

304. The AMF sends a session context request message to the SMF.

The AMF sends a session context request message to the SMF according to the received handover request message.

Specifically, the AMF obtains the identifier of the PDU session from the handover request message sent by the 5G access network device, and identifies the corresponding session management function entity to each PDU session according to the identifier of all activated PDU sessions (PDU session ID). The session management function (SMF) sends a session context service request message (ie, Nsmf_PDUSession_GetSMContext), which is used to obtain the session management context of each PDU session identified by the PDU session ID.

305. The SMF sends a session context response message to the AMF.

After receiving the session context request message sent by the AMF, the SMF sends a session context response message (ie, Nsmf_PDUSession_GetSMContext Response) to the AMF, where the session context response message carries the session context.

For example, after the SMF receives the Nsmf_PDUSession_GetSMContext service request, the SMF replies to the AMF with the Nsmf_PDUSession_GetSMContext Response, which carries the session management context (SM Context), specifically, the identifier and QoS information of each QoS flow in the PDU session. The Evolved Packet System (EPS) bearer context (EPS Bearer Context), where the EPS bearer context includes an EPS bearer identifier (Bearer ID) and QoS information.

It should be noted that, in the 5G system, the voice information carried in the session management context is called a voice stream, and the voice stream is mapped in a 4G system, which is called an EPS bearer. To ensure QoS, the following technologies may be used, including: jitter smoothing technology, packet loss processing technology, congestion control technology, echo cancellation technology, and silent compression technology, which are not limited herein.

306. The AMF selects the MME.

The AMF selects the MME according to the local configuration.

Specifically, the AMF is based on a local configuration (for example, may be a pre-configured MME identity, or a mapping relationship between a 4G tracking area identity (TAI) and a 3G routing area identity (RAI)) The MME is selected to perform SRVCC handover. Alternatively, the AMF queries the domain name system (DNS), and/or queries the network repository function (NRF) to obtain information such as the MME identity to select the MME to perform the SRVCC handover, and may also use other methods, specifically Not limited.

307. The AMF sends a first request message to the MME.

The AMF sends a first request message to the selected MME, where the first request message is a relocation request message, where the first request message includes the bearer information and the identifier of the target access network node. It can be understood that the first request message is A voice switching indication can also be carried.

Specifically, the AMF sends a relocation request message (ie, Relocation Request) to the selected MME, where the relocation request message carries the target UTRAN base station identifier (Node ID), and the source to target transparent container (Source to Target Transparent Container) , mapped UE EPS mobility management (MM) and session management (SM) context (mapped MM and SM EPS UE Context), wherein the context includes default bearer information and dedicated bearer information; single radio session Session transfer number-single radio (STN-SR), mobile station international subscriber directory number (MSISDN), SRVCC indication and other parameters.

It should be noted that the AMF obtains subscription data from the home subscriber server (HSS)/unified data management (UDM) in the previous UE registration process, and the subscription data includes the above STN-SR and MSISDN. The AMF sends the STN-SR and the MSISDN to the MME in the first request message, and the MME uses the STN-SR and the MSISDN to initiate the SRVCC to the target mobile switching center (MSC).

308. The MME obtains voice bearer information according to the bearer information.

The MME obtains the carried bearer information from the first request, and separates the voice bearer information from the bearer information.

Specifically, the MME separates the voice bearer information and the non-voice bearer information of the UE according to the EPS bearer information included in the UE EPS context carried in the first request message; or the MME separates the UE according to the SRVCC indication carried in the first request message. Voice bearer information and non-voice bearer information. Specifically, the bearer information, that is, the EPS bearer context, includes an EPS bearer ID, a QoS class identifier (QCI), a guaranteed bit rate (GBR), and a maximum bit rate (maximum bit rate, MBR) and other parameters. The value of the QCI in the voice bearer information is 1, indicating the quality of service category required for the voice session; the value of the QCI in the non-voice bearer information is not 1, for example, the value of the QCI may be other values such as 6, 7, or 8. Used to indicate the quality of service category required for Internet (Internet) services, streaming media, etc.

If the SRVCC handover indication indicates that the PS handover (ie, SRVCC with PS HO) is performed while the SRVCC is being executed, for the non-voice bearer information, the MME sends a forwarding relocation to the serving GPRS support node (SGSN). A request message (Forward Relocation Request), and a service gateway (S-GW) is allocated for the target SGSN to connect to the User plane Function (UPF)/User Area Public Data Network through the S-GW. A public data network gateway-user plane (PGW-U) is used to perform handover of a non-voice bearer to a 3G PS network.

It can be understood that the obtained voice bearer information is corresponding to or associated with the voice session. For example, the obtained voice bearer information 1 corresponds to or is associated with the voice session 1, and the voice session 1 uses the voice indicated by the voice bearer information 1. When bearer 1 performs voice service data transmission of the user, that is, voice bearer information 1 corresponds to voice session 1, or voice bearer information 1 is associated with voice session 1. It should be noted that the bearer information is the EPS bearer information. For the convenience of description, the bearer information is referred to as the bearer information in the embodiment and the subsequent embodiments.

309. The MME sends a second request message to the target MSC, so that the target MSC performs handover preparation.

The MME sends a second request message to the target MSC, where the second request message is used to request to switch the voice session performed by the UE in the 5G system to the 3G system, where the second request message carries the separated voice bearer information.

For voice bearer information, the MME may send a SRVCC request message (SRVCC PS to CS request) of the packet switched network to the circuit switched network to the target MSC according to the existing 4G SRVCC procedure. According to the existing 4G SRVCC process, the target MSC interacts with the 3G access network and the IMS to reserve resources for the SRVCC handover and complete the SRVCC handover preparation process.

It should be noted that, if the SRVCC handover indication is used to indicate that the PS handover (ie, SRVCC with PS HO) is performed while performing the SRVCC handover, the target SGSN interacts with the 3G access network for the non-voice bearer, and reserves resources for the PS HO. . The non-voice bearer is an EPS bearer, which is similar to the voice bearer.

310. The MME sends a first request response message to the AMF.

The MME sends a first request response message, that is, a Relocation Response message, to the AMF.

311. The AMF sends a handover command message to the 5G RAN.

The AMF sends a Handover Command to the 5G access network device.

312. The 5G RAN sends a handover command message to the UE.

The 5G access network device sends a handover command message (Handover Command) to the UE.

313. The UE performs voice session switching.

The UE performs voice session switching. The UE establishes a connection with the UTRAN device MSC according to the received handover command message (Handover Command). According to the existing 4G SRVCC process, the handover of the voice bearer/session from the 4G PS network to the 3G CS network (ie, SRVCC) is completed between the UE, the 3G network, and the 4G network device. It can be understood that if the SRVCC handover indication is SRVCC with PS HO, the non-voice bearer/session is switched from 4G PS to 3G PS network. Unlike the existing 4G SRVCC process, there is no need to perform a resource release process in a 4G network.

314. The MME sends a relocation complete message to the AMF.

The MME sends a Relocation Complete message to the AMF, and the AMF sends a Relocation Ack to the MME.

315. The AMF initiates an event notification service request message to the SMF.

The AMF initiates an event notification service request message (Nsmf_EventExposure_Notify) to the SMF to notify the SMF that the handover is complete.

316. The SMF initiates a process of releasing a PDU session.

The SMF initiates the process of releasing the PDU session. Specifically, the SMF initiates a process of deactivating the user plane connection of the UE in the PDU session of the 5G, releasing the user plane resources of the PDU session of the UE in the 5G, including the tunnel tunnel between the 5G access network and the 5G core network; or The SMF initiates the process of releasing the PDU session of the UE in the 5G, releasing the PDU session of the UE in the 5G; or, the SMF initiates the process of releasing the PDU session of the UE in the 5G including the QoS flow of the voice stream; for the PDU session that does not include the QoS flow of the voice stream The SMF initiates the process of deactivating the user plane connection of the PDU session.

317. The UE initiates a routing area update process, or initiates an attach procedure to register to the 3G PS network.

The UE initiates a Routing Area Update process in the 3G, or initiates an Attach process to register to the 3G PS network.

It should be noted that if the non-voice bearer/session is not transferred to the 3G PS network through the handover in the previous step, the UE may re-establish the non-voice session on the 3G PS network.

In the embodiment of the present application, the voice session of the UE in the 5G system is switched to the 3G system via the 4G core network, and the 4G access network is not required to participate in the handover, thereby reducing the handover delay, improving the handover success rate, and maintaining the voice session. Continuity.

It should be noted that, in this embodiment and subsequent embodiments, the 5G system is switched to the 3G system as an example, and the 5G system may be switched to the 2G system. The specific process is similar to the step shown in FIG. No longer.

Referring to FIG. 4, in this embodiment, the first functional entity is an access and mobility management function entity AMF, the second functional entity is a session management function entity SMF, and the third functional entity is a mobility management entity MME, in the AMF. Another embodiment of the method for voice switching in the embodiment of the present application includes:

401. The UE sends a measurement report to the 5G RAN.

The user equipment UE sends a measurement report to the access network device (5G RAN) of the 5G system.

402, 5G RAN decides to perform network switching.

The 5G RAN decides to perform network switching based on the received measurement report.

403. The 5G RAN sends a handover request message to the access and mobility management function entity AMF.

The 5G access network device sends a handover request message to the AMF, where the handover request message carries an identifier of the target access network node and a voice handover indication (ie, an SRVCC handover indication). The voice switching indication may not be carried in the handover request message.

Steps 401 to 403 are similar to the above steps 301 to 303, and are not described herein again.

404. AMF selects SMF.

The AMF determines, according to the received SRVCC indication of the handover request message (Handover Required) or the identity of the target access network node, that the voice session handover will be triggered subsequently. The switch request message may carry multiple PDU session identifiers (PDU session ID(s)), which may correspond to multiple SMFs (one or more PDU sessions correspond to one SMF; where "correspondence" means that the SMF controls the session. The AMF may select the SMF, ie, determine which (or which) SMF to send the session context request message (Nsmf_PDUSession_GetSMContext).

For example, the AMF may determine which (/some) is based on the network slice selection assistance information (NSSAI) and/or the data network name (DNN) corresponding to the PDU Session identified by the PDU Session ID. The PDU session may support voice flow to send a session context request message (Nsmf_PDUSession_GetSMContext) to the SMF corresponding to the PDU Session; or, depending on the NSFAI and/or DNN supported by the SMF, determine which SMF may support the IP multimedia system ( IP multimedia subsystem (IMS) voice session, thereby sending a session context request message (Nsmf_PDUSession_GetSMContext) to the SMF.

405. The AMF sends a session context request message to the SMF.

The AMF sends a session context request message to the SMF according to the received handover request message, where the session context request message carries an SRVCC indication.

406. The SMF sends a session context response message to the AMF.

After receiving the session context request message sent by the AMF, the SMF sends a session context response message (ie, Nsmf_PDUSession_GetSMContext Response) to the AMF, where the session context response message carries a session context, and the session context carries or indicates voice bearer information.

It should be noted that the SM context carried in the session context response message includes voice stream QoS flow information, mapped voice EPS bearer information, and SRVCC flag. That is, the SMF marks which QoS flow/mapped EPS bearer is the voice stream/bearer, for example, using SRVCC Indication as a flag. Alternatively, the SM context carried in the session context response message includes only voice stream QoS flow information and mapped voice EPS bearer information, and does not include other non-voice stream information and its mapped EPS bearer information. This does not require carrying the SRVCC tag.

407. The AMF selects the MME.

Specifically, the AMF is based on a local configuration (for example, may be a pre-configured MME identity, or a mapping relationship between a 4G tracking area identity (TAI) and a 3G routing area identity (RAI)) The MME is selected to perform SRVCC handover. Alternatively, the AMF queries the domain name system (DNS), and/or queries the network repository function (NRF) to obtain information such as the MME identity to select the MME to perform the SRVCC handover. The AMF selects the MME to perform the SRVCC, and other methods may also be used, which are not limited herein.

408. The AMF sends a first request message to the MME.

The AMF sends a first request message to the selected MME, where the first request message is a relocation request message, where the first request message includes an identifier of the target access network node, and the first request message may further carry a voice handover indication (SRVCC Indication) The first request message includes only voice bearer information.

Specifically, the AMF sends a relocation request message (ie, Relocation Request) to the selected MME, where the relocation request message carries the target UTRAN base station identifier (Node ID), and the source to target transparent container (Source to Target Transparent Container) The mapped MM and SM EPS UE Context, where the context includes the default bearer and dedicated bearer information; the session transfer number-single radio (STN) -SR), mobile station international subscriber directory number (MSISDN), SRVCC indication and other parameters.

It should be noted that, in the mapped UE EPS mobility management MM and the session management SM context, the SM context only contains voice bearer information, and does not include other non-voice bearer information. For example, if the session context response message (Nsmf_PDUSession_GetSMContext) carries the SRVCC flag, the AMF carries the EPS bearer information of the QoS flow mapping of the SRVCC tag carried in the session context response message, that is, the voice EPS bearer information, in the first request message (Relocation Request). )in.

Alternatively, the AMF sends an SRVCC PS network to CS network handover request message (SRVCC PS to CS Request) to the MME, which carries an international mobile subscriber identity (IMSI), a target UTRAN/GERAN node identifier, an STN-SR, an MSISDN. Parameters such as Source to Target Transparent Container and MM Context trigger SRVCC switching of voice flow QoS flow.

It should be noted that the AMF obtains subscription data from the home subscriber server (HSS)/unified data management (UDM) in the previous UE registration process, and the subscription data includes the above STN-SR and MSISDN. The AMF sends the STN-SR and the MSISDN to the MME in the first request message, and the MME uses the STN-SR and the MSISDN to initiate the SRVCC to the target mobile switching center (MSC).

409. The MME sends a second request message to the target MSC, so that the target MSC performs handover preparation.

The MME sends a second request message to the target MSC, where the second request message is used to request that the voice session performed by the UE in the 5G system is switched to the 3G system, and the second request message carries the received voice bearer information.

For voice bearer information, the MME may send an SRVCC request message (SRVCC PS to CS request) of the packet switched network to the circuit switched network to the MSC according to the existing 4G SRVCC procedure. According to the existing 4G SRVCC process, the target MSC interacts with the 3G access network and the IMS to reserve resources for the SRVCC handover and complete the SRVCC handover preparation process.

410. The MME sends a first request response message to the AMF.

The MME sends a first request response message, that is, a Relocation Response message, to the AMF.

411. The AMF sends a handover command message to the 5G RAN.

The AMF sends a Handover Command to the 5G access network device.

412. The 5G RAN sends a handover command message to the UE.

The 5G access network device sends a handover command message (Handover Command) to the UE.

413. The UE performs voice session switching.

The UE performs voice session switching.

414. The MME sends a relocation complete message to the AMF.

The MME sends a Relocation Complete message to the AMF, and the AMF sends a Relocation Ack to the MME.

415. The AMF initiates an event notification service request message to the SMF.

The AMF initiates an event notification service request message (Nsmf_EventExposure_Notify) to the SMF to notify the SMF that the handover is complete.

416. The SMF initiates a process of releasing a PDU session.

The SMF initiates the process of releasing the PDU session.

417. The UE initiates a routing area update process, or initiates an attach procedure to register to the 3G PS network.

The UE initiates a Routing Area Update process in the 3G, or initiates an Attach process to register to the 3G PS network.

Steps 410 to 417 are similar to the above steps 310 to 317, and are not described herein again.

In the embodiment of the present application, the voice session of the UE in the 5G system is switched to the 3G system via the 4G core network device MME, and the 4G access network is not required to participate in the handover, thereby reducing the handover delay and improving the handover success rate and maintaining The continuity of the voice conversation.

It should be noted that, in this embodiment, the separation of the voice bearer is performed on the SMF side, and the SMF sends the separated voice bearer to the AMF, and the separation process of the voice bearer can also be performed on the AMF side, and the complete bearer sent by the AMF from the SMF. The voice bearer is separated from the information, and then only the voice bearer is sent to the MME. The specific process is not described here.

Referring to FIG. 5, in this embodiment, the first functional entity is an access and mobility management function entity AMF, the second functional entity is a session management function entity SMF, and the third functional entity is a mobility management entity MME, at 5G. In another embodiment, the method for the voice switching in the embodiment of the present application includes:

501. The UE sends a measurement report to the 5G RAN.

The user equipment UE sends a measurement report to the access network device (5G RAN) of the 5G system.

502, 5G RAN decides to perform network switching.

The 5G RAN decides to perform network switching based on the received measurement report.

Steps 501 to 502 are similar to the above steps 301 to 302, and are not described herein again.

503. The 5G RAN sends a handover request message to the access and mobility management function entity AMF.

The 5G access network device sends a handover request message to the AMF, where the handover request message carries the session identification information and the identifier of the target access network node. The handover request message further carries parameters such as a generic source to target transparent container and an SRVCC HO Indication.

It should be noted that the session identifier information indicates a voice PDU session ID, and the voice PDU session identifier corresponds to a voice date radio bearer (Voice DRB)/voice QoS flow. An identifier (ID) of the PDU session; or the session identification information includes a session identifier of each of the plurality of PDU sessions currently performed by the UE (one session identifier corresponding to each PDU session), wherein one session identifier is marked as a voice session (eg, including voice) Indicates voice indication).

The SRVCC HO Indication indicates that this is an SRVCC handover. Further, the SRVCC HO Indication may indicate that the PS handover (SRVCC with PS HO) is performed while the SRVCC is being executed, or the SR handover (SRVCC without PS HO) is not performed while the SRVCC is being executed.

504. The AMF selects an SMF according to the voice PDU session identifier.

The AMF determines, according to the SRVCC indication of the received handover request message (Handover Required), that the voice session handover will be triggered subsequently, and the AMF selects the SMF according to the voice PDU session identifier.

For example, the AMF selects the SMF corresponding to the voice PDU session ID according to the voice PDU session ID in the Handover Required message, that is, the SMF that supports the voice PDU session of the UE.

505. The AMF sends a session context request message to the SMF.

The AMF sends a session context request message to the SMF according to the received handover request message, where the session context request message carries an SRVCC indication.

506. The SMF sends a session context response message to the AMF.

After receiving the session context request message sent by the AMF, the SMF sends a session context response message (ie, Nsmf_PDUSession_GetSMContext Response) to the AMF, where the session context response message carries a session context, and the session context carries or indicates voice bearer information.

507. The AMF selects the MME.

The AMF selects the MME. For details, see step 407, and details are not described herein.

508. The AMF sends a first request message to the MME.

The AMF sends a first request message to the selected MME, where the first request message is a relocation request message, where the first request includes an identifier of the target access network node and/or a voice handover indication (SRVCC Indication), the first request Only voice bearer information is included.

509. The MME sends a second request message to the target MSC, so that the target MSC performs handover preparation.

The MME sends a second request message to the target MSC, where the second request message is used to request that the voice session performed by the UE in the 5G system is switched to the 3G system, and the second request message carries the received voice bearer information.

510. The MME sends a first request response message to the AMF.

The MME sends a first request response message, that is, a Relocation Response message, to the AMF.

511. The AMF sends a handover command message to the 5G RAN.

The AMF sends a Handover Command to the 5G access network device.

The 512, 5G RAN sends a handover command message to the UE.

The 5G access network device sends a handover command message (Handover Command) to the UE.

513. The UE performs voice session switching.

The UE performs voice session switching.

514. The MME sends a relocation complete message to the AMF.

The MME sends a Relocation Complete message to the AMF, and the AMF sends a Relocation Ack to the MME.

515. The AMF initiates an event notification service request message to the SMF.

The AMF initiates an event notification service request message (Nsmf_EventExposure_Notify) to the SMF to notify the SMF that the handover is complete.

516. The SMF initiates a process of releasing a PDU session.

The SMF initiates the process of releasing the PDU session.

517. The UE initiates a routing area update process, or initiates an attach procedure to register to the 3G PS network.

The UE initiates a Routing Area Update process in the 3G, or initiates an Attach process to register to the 3G PS network.

Steps 505 to 517 are similar to the above steps 405 to 417, and are not described herein again.

In the embodiment of the present application, the voice session of the UE in the 5G system is switched to the 3G system via the 4G core network device MME, and the 4G access network is not required to participate in the handover, thereby reducing the handover delay and improving the handover success rate and maintaining The continuity of the voice conversation.

It should be noted that steps 505 to 517 can also be replaced with steps 304 to 317 in the embodiment of FIG. 3, and details are not described herein again.

After the voice session of the embodiment shown in FIG. 3 to FIG. 5 is switched from the 5G system to the 3G system, the 3G system can be switched back to the 5G system. Referring to FIG. 6, another method for voice switching in the embodiment of the present application is used. Examples include:

601. The UE sends a measurement report to the 5G RAN.

The user equipment UE sends a measurement report to the access network device (5G RAN) of the 5G system.

602, 5G RAN decides to perform network switching.

The 5G RAN decides to perform network switching based on the received measurement report.

603. The 5G RAN sends a handover request message to the access and mobility management function entity AMF.

The 5G access network device sends a handover request message to the AMF, where the handover request message carries an identifier of the target access network node and a voice handover indication (ie, an SRVCC handover indication).

604. The AMF selects the SMF.

The AMF determines, according to the SRVCC indication of the received handover request message (Handover Required), that the voice session handover will be triggered subsequently. The identifier of the PDU session carried in the handover request message (PDU session ID(s)) may correspond to multiple SMFs (one or more PDU sessions correspond to one SMF; where "correspondence" means that the SMF controls the establishment and modification of the session. And release, maintain the context of the session, etc.), the AMF may select the SMF, ie, determine which (or which) SMF to send the session context request message (Nsmf_PDUSession_GetSMContext).

605. The AMF sends a session context request message to the SMF.

The AMF sends a session context request message to the SMF according to the received handover request message, where the session context request message carries an SRVCC indication.

606. The SMF sends a session context response message to the AMF.

After receiving the session context request message sent by the AMF, the SMF sends a session context response message (ie, Nsmf_PDUSession_GetSMContext Response) to the AMF, where the session context response message carries a session context, and the session context carries or indicates voice bearer information.

607. The AMF selects the MME.

The AMF selects the MME according to the local configuration.

608. The AMF sends a first request message to the MME.

The AMF sends a first request message to the selected MME, where the first request message is a relocation request message, where the first request includes an identifier of the target access network node and/or a voice handover indication (SRVCC Indication), the first request Only voice bearer information is included.

609. The MME sends a second request message to the target MSC, so that the target MSC performs handover preparation.

The MME sends a second request message to the target MSC, where the second request message is used to request that the voice session performed by the UE in the 5G system is switched to the 3G system, and the second request message carries the received voice bearer information.

610. The MME sends a first request response message to the AMF.

The MME sends a first request response message, that is, a Relocation Response message, to the AMF.

611. The AMF sends a handover command message to the 5G RAN.

The AMF sends a Handover Command to the 5G access network device.

612. The 5G RAN sends a handover command message to the UE.

The 5G access network device sends a handover command message (Handover Command) to the UE.

613. The UE performs voice session switching.

The UE performs voice session switching.

614. The MME sends a relocation complete message to the AMF.

The MME sends a Relocation Complete message to the AMF, and the AMF sends a Relocation Ack to the MME.

615. The AMF initiates an event notification service request message to the SMF.

The AMF initiates an event notification service request message (Nsmf_EventExposure_Notify) to the SMF to notify the SMF that the handover is complete.

616. The SMF initiates a process of releasing a PDU session.

The SMF initiates the process of releasing the PDU session.

617. The UE initiates a routing area update process, or initiates an attach procedure to register to the 3G PS network.

The UE initiates a Routing Area Update process in the 3G, or initiates an Attach process to register to the 3G PS network.

Steps 601 to 617 are similar to the above steps 301 to 317, or steps 401 to 417, or steps 501 to 517, and are not described herein again.

618. The UE may return to the 5G system by using the cell in the idle state.

The UE can return to the 5G system through the cell selection in the idle state. Specifically, the MSC may indicate to the UTRAN that the UE is returned to the 5G RAN after the end of the SRVCC voice session, for example, providing the UTRAN with the last used 5G public land mobile network identity (PLMN ID), or indicating the SRVCC. The voice call ends.

Based on the indication of the MSC, the UTRAN performs a redirection process to redirect the UE to the 5G RAN, that is, the UE is configured to measure the 5G neighboring cell by using the measurement configuration message; and based on the UE's measurement report, the UTRAN sends the RR Connection Release or RRC Connection Release message to the UE. The 5G cell information (eg, frequency, cell identifier) is carried as the redirection information, so that the UE selects the 5G cell according to the redirection information.

After the UE resides in the 5G cell, the registration request is sent to the AMF through the 5G RAN, and the registration request may carry the PDU session reactivation information (PDU Session(s) to be re-activated) or the uplink data status (UDS). ), thereby instructing the SMF to reactivate the user plane connection by re-activating the user plane connection of the PDU Session deactivated by the user plane in the SRVCC process, thereby continuing data transmission. The PDU session status may also be carried in the registration request to synchronize the PDU session state between the UE and the AMF/SMF, and delete the context of the released PDU session.

In the embodiment of the present application, the voice session of the UE in the 5G system is switched to the 3G system via the 4G core network device MME, and the 4G access network is not required to participate in the handover, thereby reducing the handover delay and improving the handover success rate, and Return to the 5G system from the 3G system to maintain the continuity of the voice session.

It should be noted that, in the embodiment shown in FIG. 3 to FIG. 6 , the 3G UTRAN network can be replaced with the 2G GERAN network. For convenience of description, only the 3G UTRAN network is illustrated.

The method for voice switching in the embodiment of the present application is described above. The mobility management entity, the access and mobility management function entity, and the radio access network device in the embodiments of the present application are separately described. Referring to FIG. 7, the first The management entity is a mobility management entity. One embodiment of the mobility management entity in this embodiment of the present application includes:

The receiving unit 701 is configured to receive a first request sent by the second function entity, where the first request includes the bearer information and the identifier of the target access network node, where the first request is used to request that the user equipment UE is in progress The voice session is switched from the first communication system to the target communication system, the second function entity is a device in the first communication system, and the first function entity is a device in the second communication system;

The first obtaining unit 702 is configured to acquire voice bearer information according to the bearer information.

a first sending unit 703, configured to send a second request to the target mobile switching center MSC, where the target MSC serves the target access network node, the target MSC is a device in the target communication system, and the second request And a method for requesting that the voice session corresponding to the voice bearer information is switched from the first communication system to the target communication system.

In a possible implementation, the first sending unit 703 is specifically configured to:

Determining the target MSC according to the identifier of the target access network node;

Sending a second request to the target MSC to cause the target MSC to reserve a handover resource for the voice session.

In a feasible implementation manner, the sending unit 703 is further specifically configured to:

Determining the target MSC according to the voice switching indication;

Sending a second request to the target MSC, so that the target MSC reserves a handover resource for the voice session, and the second request carries the voice handover indication.

In a feasible implementation manner, the mobility management entity further includes:

The second obtaining unit 704 is configured to acquire, according to the first request, a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN;

The determining unit 705 is configured to determine the target MSC according to the STN-SR and the MSISDN.

In a possible implementation manner, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolved radio access network GERAN identifier.

In a feasible implementation manner, there is no handover evolved universal terrestrial radio access network E-UTRAN cell in the second communication system, where there is a switched universal terrestrial radio access network UTRAN/ Global mobile communication system and evolved radio access network GERAN cell.

In a possible implementation, the voice switching indication is further used to indicate that the packet switched PS network is switched while performing the single radio frequency voice call continuity RVCC, where the first functional entity further includes:

The second sending unit 706 is configured to send a third request to the target general packet radio service support node SGSN, where the second request is used to instruct the target SGSN to switch the non-voice bearer to the PS network of the target communication system.

Referring to FIG. 8 , the first functional entity is the access and mobility management function entity AMF, the second function entity is the session management function entity SMF, and the third function entity is the mobility management entity MME. One embodiment of a mobility management functional entity includes:

The receiving unit 801 is configured to receive a first request sent by the radio access network device, where the first request includes an identifier of a target access network node, where the first request is used to request a voice session that is ongoing by the user equipment UE Switching from the first communication system to the target communication system, the first functional entity is a device in the first communication system, and the wireless access network device is a device of the first communication system;

The processing unit 802 is configured to determine a second functional entity corresponding to the voice session, obtain voice bearer information of the voice session from the second function entity, where the second function entity is a device of the first communication system ;

The sending unit 803 is configured to send a second request to the third functional entity, where the second request includes the voice bearer information and an identifier of the target access network node, where the third functional entity is a second communications system In the device.

In a possible implementation, the second request is used to request the third functional entity to send a third request to the target mobile switching center MSC, where the target MSC serves the target access network node, A third request is for requesting to switch the voice session from the first communication system to the target communication system, the target MSC being a device in a target communication system.

In a possible implementation, the first request further includes session identifier information, where the session identifier information includes a session identifier of the voice session, and the processing unit is specifically configured to:

Determining, according to the session identification information, a session identifier of the voice session, and determining, according to the session identifier of the voice session, the second function entity.

In a feasible implementation, the processing unit 802 is further specifically configured to:

A second functional entity having voice conferencing support capability is determined from at least two second functional entities corresponding to all sessions of the UE.

In a possible implementation, the first request further includes session identification information, and the processing unit 802 is specifically configured to:

Determining, according to the session identification information carried in the first request, network slice selection assistance information NSSAI and/or data network name DNN;

Determining, according to the NSSAI and/or the DNN, that the second functional entity corresponding to the NSSAI and/or the DNN has the voice session support capability;

Determining the second functional entity.

In a possible implementation, the first request further includes session identification information, where the session identification information includes a session identifier of the voice session, and the processing unit 802 is further configured to:

Sending a fourth request to the second function entity, where the fourth request carries a session identifier of the voice session;

And receiving the voice bearer information corresponding to the session identifier of the voice session sent by the second function entity.

In a possible implementation, the first request further includes a voice switching indication, and the processing unit 802 is further configured to:

Sending a fifth request to the second function entity, where the fifth request carries the voice switching indication;

Receiving, by the second functional entity, the voice bearer information sent according to the voice switching indication.

In a possible implementation, the sending unit 803 is specifically configured to:

Obtaining a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN;

Sending the second request to the third functional entity, where the second request carries the STN-SR and the MSISDN.

In a possible implementation manner, the identifier of the target access network node includes a target universal terrestrial radio access network identifier or a target global mobile communication system and an evolved radio access network GERAN identifier.

In a feasible implementation manner, there is no handover evolved universal terrestrial radio access network E-UTRAN cell in the second communication system, where there is a switched universal terrestrial radio access network UTRAN/ Global mobile communication system and evolved radio access network GERAN cell.

In a possible implementation manner, the first functional entity further includes:

a determining unit 804, configured to determine the third functional entity according to the identifier of the preset third functional entity;

or,

Querying the domain name system DNS and/or the network storage function function entity NRF to obtain the identifier of the third functional entity;

Determining the third functional entity according to the identifier of the third functional entity.

Referring to FIG. 9, the first functional entity is the access and mobility management function entity AMF, the second function entity is the session management function entity SMF, and the third function entity is the mobility management entity MME. One embodiment of a network device includes:

The receiving unit 901 is configured to receive a measurement report sent by the user equipment, where the radio access network device is a device of the first communication system;

The sending unit 902 is configured to send, according to the measurement report, a first request to the first functional entity, where the first request is used to request to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication system The first functional entity is a device in the first communication system;

The first request carries the session identifier information, where the session identifier information includes only the session identifier of the voice session, or the session identifier information includes a session identifier that carries a voice indication.

In a possible implementation, the first request is used to request the first functional entity to determine a second functional entity according to the session identifier, and obtain voice bearer information of the voice session from the second functional entity. And switching the voice session from the first communication system to the target communication system by a third functional entity, the second functional entity being a device in the first communication system, the third functional entity It is a device in the second communication system.

In a feasible implementation manner, the radio access network device further includes:

The first determining unit 903 is configured to determine, according to the voice stream information or the voice data radio bearer information of the UE, and the measurement report, to switch the ongoing voice session of the UE from the first communications system to the The target communication system.

In a feasible implementation manner, the radio access network device further includes:

The second determining unit 904 is configured to determine a session identifier of the voice session according to at least the voice stream information of the UE or the voice data radio bearer information.

In a possible implementation, the first request is for requesting to switch the voice session from the first communication system to a circuit switched domain of the target communication system.

The mobile management entity, the access and mobility management function entity, and the radio access network device in the embodiments of the present application are respectively described in detail from the perspective of the modular functional entity, and the following is a hardware processing perspective. The mobility management entity, the access and mobility management function entity, and the radio access network device in the application embodiment are respectively described in detail.

10 is a schematic structural diagram of a mobility management entity according to an embodiment of the present application. The mobility management entity 1000 may generate a large difference due to different configurations or performances, and may include one or more processors (central processing units, CPU). 1001 (eg, one or more processors) and memory 1009, one or more storage media 1008 that store application 1007 or data 1006 (eg, one or one storage device in Shanghai). Among them, the memory 1009 and the storage medium 1008 may be short-term storage or persistent storage. The program stored on the storage medium 1008 may include one or more modules (not shown), each of which may include a series of instruction operations in the mobility management entity. Still further, the processor 1001 can be configured to communicate with the storage medium 1008 to perform a series of instruction operations in the storage medium 1008 on the mobility management entity 1000.

The mobility management entity 1000 can also include one or more power sources 1002, one or more wired or wireless network interfaces 1003, one or more input and output interfaces 1004, and/or one or more operating systems 1005, such as Windows Serve, Mac OS X, Unix, Linux, FreeBSD, and more. It will be understood by those skilled in the art that the mobility management entity structure shown in FIG. 10 does not constitute a limitation on the mobility management entity, and may include more or less components than those illustrated, or combine some components, or different components. Arrangement.

The following describes the components of the mobility management entity in conjunction with Figure 10:

The processor 1001 is a control center of the mobility management entity and can be processed in accordance with the set method of maintaining voice continuity. The processor 1001 connects various portions of the entire mobility management entity using various interfaces and lines, performs a mobility management entity by running or executing software programs and/or modules stored in the memory 1009, and invoking data stored in the memory 1009. Various functions and processing data to maintain the continuity of the voice session.

The memory 1009 can be used to store software programs and modules, and the processor 1001 executes various functional applications and data processing of the mobility management entity 1000 by running software programs and modules stored in the memory 1009. The memory 1009 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application required for at least one function (such as a separate voice bearer, etc.), and the like; the storage data area may be stored according to the mobile management entity. Use the created data (such as SRVCC instructions, etc.) and so on. Further, the memory 1009 may include a high speed random access memory, and may also include a nonvolatile memory such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device. The program of the voice switching method and the received data stream provided in the embodiment of the present application are stored in a memory, and the processor 1001 is called from the memory 1009 when needed for use.

FIG. 11A is a schematic structural diagram of an access and mobility management function entity according to an embodiment of the present application, and FIG. 11A is referred to. In the case of employing an integrated unit, FIG. 11A shows a possible structural diagram of the access and mobility management function entities involved in the above embodiments. The access and mobility management function entity 1100 includes a processing unit 1102 and a communication unit 1103. The processing unit 1102 is configured to control and manage the actions of the access and mobility management function entity. For example, the processing unit 1102 is configured to support the access and mobility management function entity to perform step 404, step 407 in FIG. 4, and/or Other processes for the techniques described herein. The communication unit 1103 is configured to support communication between the access and mobility management function entity and other network entities. The access and mobility management function entity may also include a storage unit 1101 for storing program codes and data of the access and mobility management function entities.

The processing unit 1102 can be a processor or a controller, for example, a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), and an application-specific integrated circuit (application-specific). Integrated circuit (ASIC), field programmable gate array (FPGA) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. It is possible to implement or carry out the various illustrative logical blocks, modules and circuits described in connection with the present disclosure. The processor can also be a combination of computing functions, for example, including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like. The communication unit 1103 can be a communication interface, a transceiver, a transceiver circuit, etc., wherein the communication interface is a collective name and can include one or more interfaces, such as a transceiver interface. The storage unit 1101 may be a memory.

When the processing unit 1102 is a processor, the communication unit 1103 is a communication interface, and the storage unit 1101 is a memory, the access and mobility management function entity involved in the embodiment of the present application may be the access and mobility management shown in FIG. 10B. Functional entity.

Referring to FIG. 11B, the access and mobility management function entity 1110 includes a processor 1112, a communication interface 1113, and a memory 1111. Alternatively, the access and mobility management functional entity 1110 may also include a bus 1114. The communication interface 1113, the processor 1112, and the memory 1111 may be connected to each other through a bus 1114; the bus 1114 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA). Bus, etc. The bus 1114 can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in FIG. 11B, but it does not mean that there is only one bus or one type of bus.

FIG. 12 is a schematic structural diagram of a radio access network device according to an embodiment of the present disclosure. The radio access network device 1200 may generate a large difference due to different configurations or performances, and may include one or more processors (central Processing units (CPU) 1201 (eg, one or more processors) and memory 1209, one or more storage media 1208 that store application 1207 or data 1206 (eg, one or one storage device in Shanghai). Among them, the memory 1209 and the storage medium 1208 may be short-term storage or persistent storage. The program stored on storage medium 1208 may include one or more modules (not shown), each of which may include a series of instruction operations in the wireless access network device. Still further, the processor 1201 can be configured to communicate with the storage medium 1208 to perform a series of instruction operations in the storage medium 1208 on the wireless access network device 1200.

The wireless access network device 1200 can also include one or more power sources 1202, one or more wired or wireless network interfaces 1203, one or more input and output interfaces 1204, and/or one or more operating systems 1205, such as Windows. Serve, Mac OS X, Unix, Linux, FreeBSD, etc. It will be understood by those skilled in the art that the mobility management entity structure shown in FIG. 12 does not constitute a limitation on the mobility management entity, and may include more or less components than those illustrated, or combine some components, or different components. Arrangement.

The components of the radio access network device are specifically described below with reference to FIG. 12:

The processor 1201 is a control center of the radio access network device and can be processed according to the set method of maintaining voice continuity. The processor 1201 connects various portions of the entire radio access network device using various interfaces and lines, performs wireless connections by running or executing software programs and/or modules stored in the memory 1209, and recalling data stored in the memory 1209. The various functions of the networked device and the processing of data to maintain the continuity of the voice session.

The memory 1209 can be used to store software programs and modules, and the processor 1201 executes various functional applications and data processing of the wireless access network device 1200 by running software programs and modules stored in the memory 1209. The memory 1209 can mainly include a storage program area and a storage data area, wherein the storage program area can store an operating system, an application required for at least one function (such as a separate voice bearer, etc.), and the like; the storage data area can be stored according to the wireless access network. Data created by the use of the device (such as SRVCC instructions, etc.). Moreover, memory 1209 can include high speed random access memory, and can also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device. The program of the voice switching method and the received data stream provided in the embodiment of the present application are stored in a memory, and the processor 1201 is called from the memory 1209 when it is needed.

The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be from a website site, computer, server or data center Transmission to another website site, computer, server or data center via wired (eg coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (eg infrared, wireless, microwave, etc.). The computer readable storage medium can be any available media that can be stored by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (such as a solid state disk (SSD)) or the like.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application, in essence or the contribution to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium. A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program code. .

Claims (44)

1. A method for voice switching, comprising:

   Receiving, by the first functional entity, the first request sent by the second functional entity, where the first request includes the bearer information and the identifier of the target access network node, where the first request is used to request the ongoing voice session of the user equipment UE Switching from the first communication system to the target communication system, the second functional entity is a device in the first communication system, and the first functional entity is a device in the second communication system;

   The first functional entity acquires voice bearer information according to the bearer information;

   The first functional entity sends a second request to the target mobile switching center MSC, the target MSC serves the target access network node, the target MSC is a device in the target communication system, and the second request is used for Requesting to switch the voice session corresponding to the voice bearer information from the first communication system to the target communication system.
2. The method according to claim 1, wherein the first functional entity sends a second request to the target mobile switching center MSC, including:

   Determining, by the first functional entity, the target MSC according to the identifier of the target access network node;

   The first functional entity sends a second request to the target MSC to cause the target MSC to reserve a handover resource for the voice session.
3. The method according to claim 1, wherein the first request further includes a voice switching indication, and the first function entity sends a second request to the target mobile switching center MSC, including:

   Determining, by the first functional entity, the target MSC according to the voice switching indication;

   The first function entity sends a second request to the target MSC, so that the target MSC reserves a handover resource for the voice session, and the second request carries the voice handover indication.
4. The method according to any one of claims 1 to 3, wherein the method further comprises:

   The first functional entity acquires a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN according to the first request;

   The first functional entity determines the target MSC according to the STN-SR and the MSISDN.
5. The method according to any one of claims 1 to 4, wherein the identity of the target access network node comprises a target universal terrestrial radio access network UTRAN identity or a target global mobile communication system and an evolved radio access network. GERAN logo.
6. The method according to claim 3, wherein the voice switching indication is further used to indicate that performing a packet switched PS handover while performing a single radio voice call continuity SRVCC, the method further comprising:

   The first functional entity sends a third request to the target general packet radio service support node SGSN, the second request is used to instruct the target SGSN to switch the non-voice bearer to the PS network of the target communication system.
7. A method for voice switching, comprising:

   Receiving, by the first function entity, the first request sent by the radio access network device, where the first request includes an identifier of the target access network node, where the first request is used to request that the user equipment UE is performing a voice session from the first a communication system is switched to the target communication system, the first functional entity is a device in the first communication system, and the wireless access network device is a device of the first communication system;

   Determining, by the first functional entity, a second functional entity corresponding to the voice session, acquiring, from the second functional entity, voice bearer information of the voice session, where the second functional entity is a device of the first communication system ;

   Transmitting, by the first functional entity, a second request to the third functional entity, where the second request includes the voice bearer information and an identifier of the target access network node, where the third functional entity is a second communication system In the device.
8. The method according to claim 7, wherein the second request is for requesting the third functional entity to send a third request to the target mobile switching center MSC, the target MSC serving the target access network a node, the third request for requesting to switch the voice session from the first communication system to the target communication system, the target MSC being a device in a target communication system.
9. The method according to claim 7, wherein the first request further comprises session identification information, the session identification information includes a session identifier of the voice session, and the first functional entity determines that the voice session corresponds to The second functional entity, including:

   The first functional entity determines a session identifier of the voice session according to the session identifier information, and determines the second function entity according to the session identifier of the voice session.
10. The method according to claim 7, wherein the determining, by the first functional entity, the second functional entity corresponding to the voice session comprises:

    The first functional entity determines a second functional entity having a voice session support capability from at least two second functional entities corresponding to all sessions of the UE.
11. The method according to claim 7, wherein the first request further includes session identification information, and the first functional entity determines the second functional entity corresponding to the voice session, including:

    Determining, by the first functional entity, the network slice selection assistance information NSSAI and/or the data network name DNN according to the session identification information carried in the first request;

    Determining, by the first functional entity, the NSSAI and/or the second functional entity corresponding to the DNN to have the voice session support capability according to the NSSAI and/or the DNN;

    The first functional entity determines the second functional entity.
12. The method according to any one of claims 7 to 11, wherein the first request further includes session identification information, the session identification information includes a session identifier of the voice session, and the The second functional entity acquires the voice bearer information of the voice session, including:

    Transmitting, by the first functional entity, a fourth request to the second functional entity, where the fourth request carries a session identifier of the voice session;

    The first function entity receives the voice bearer information corresponding to the session identifier of the voice session sent by the second function entity.
13. The method according to any one of claims 7 to 11, wherein the first request further includes a voice switching indication, and the acquiring, by the second functional entity, voice bearer information of the voice session, include:

    The first function entity sends a fifth request to the second function entity, where the fifth request carries the voice switching indication;

    The first functional entity receives the voice bearer information sent by the second functional entity according to the voice switching indication.
14. The method according to any one of claims 7 to 13, wherein the first functional entity sends a second request to the third functional entity, including:

    The first functional entity acquires a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN;

    The first functional entity sends the second request to the third functional entity, where the second request carries the STN-SR and the MSISDN.
15. The method according to any one of claims 7-14, wherein the identity of the target access network node comprises a target universal terrestrial radio access network identity or a target global mobile communication system and an evolved radio access network GERAN Logo.
16. The method of claim 7, wherein the method further comprises:

    Determining, by the first functional entity, the third functional entity according to the identifier of the preset third functional entity;

    or,

    The first functional entity queries the domain name system DNS and/or the network storage function entity NRF to obtain the identifier of the third functional entity;

    The first functional entity determines the third functional entity according to the identifier of the third functional entity.
17. A method for voice switching, comprising:

    The radio access network device receives the measurement report sent by the user equipment, and the radio access network device is the device of the first communication system;

    The radio access network device sends a first request to the first functional entity according to the measurement report, where the first request is used to request to switch the ongoing voice session of the user equipment UE from the first communication system to the target communication System, the first functional entity is a device in the first communication system;

    The first request carries the session identifier information, where the session identifier information includes only the session identifier of the voice session, or the session identifier information includes a session identifier that carries a voice indication.
18. The method according to claim 17, wherein the first request is used to request the first functional entity to determine a second functional entity according to the session identifier, and obtain the voice session from the second functional entity. Voice bearer information, which in turn switches the voice session from the first communication system to the target communication system by a third functional entity, the second functional entity being a device in the first communication system, The third functional entity is a device in the second communication system.
19. The method of claim 17, wherein the method further comprises:

    The access network device determines to switch the voice session from the first communication system to the target communication system according to at least the voice stream information of the UE or the voice data radio bearer information, and the measurement report.
20. The method of claim 17, wherein the method further comprises:

    The access network device determines the session identifier of the voice session according to at least the voice stream information of the UE or the voice data radio bearer information.
21. The method according to any one of claims 17 to 20, wherein the first request is for requesting to switch the voice session from the first communication system to a circuit switched domain of the target communication system .
22. A functional entity, wherein the functional entity is a first functional entity, including:

    a receiving unit, configured to receive a first request sent by a second functional entity, where the first request includes bearer information and an identifier of a target access network node, where the first request is used to request a voice that is ongoing by the user equipment UE The session is switched from the first communication system to the target communication system, the second functional entity is a device in the first communication system, and the first functional entity is a device in the second communication system;

    a first acquiring unit, configured to acquire voice bearer information according to the bearer information;

    a first sending unit, configured to send a second request to the target mobile switching center MSC, where the target MSC serves the target access network node, the target MSC is a device in the target communication system, and the second request is used by The requesting to switch the voice session corresponding to the voice bearer information from the first communication system to the target communication system.
23. The first functional entity according to claim 22, wherein the first sending unit is specifically configured to:

    Determining the target MSC according to the identifier of the target access network node;

    Sending a second request to the target MSC to cause the target MSC to reserve a handover resource for the voice session.
24. The first functional entity according to claim 22, wherein the first request further includes a voice switching indication, and the first sending unit is further configured to:

    Determining the target MSC according to the voice switching indication;

    Sending a second request to the target MSC, so that the target MSC reserves a handover resource for the voice session, and the second request carries the voice handover indication.
25. The first functional entity according to any one of claims 22 to 24, wherein the first functional entity further comprises:

    a second acquiring unit, configured to acquire a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN according to the first request;

    a determining unit, configured to determine a target MSC according to the STN-SR and the MSISDN.
26. The mobility management entity according to any one of claims 22-25, wherein the identity of the target access network node comprises a target universal terrestrial radio access network identity or a target global mobile communication system and an evolved radio access Network GERAN logo.
27. The first functional entity according to claim 24, wherein the voice switching indication is further used to indicate that the packet switched PS network is switched while performing a single radio voice call continuity RVCC, the first functional entity further comprising :

    And a second sending unit, configured to send a third request to the target general packet radio service support node SGSN, where the second request is used to instruct the target SGSN to switch the non-voice bearer to the PS network of the target communication system.
28. A functional entity, wherein the functional entity is a first functional entity, including:

    a receiving unit, configured to receive a first request sent by a radio access network device, where the first request includes an identifier of a target access network node, where the first request is used to request a voice session that is ongoing by the user equipment UE The first communication system is switched to the target communication system, the first functional entity is a device in the first communication system, and the wireless access network device is a device of the first communication system;

    a processing unit, configured to determine a second functional entity corresponding to the voice session, and obtain voice bearer information of the voice session from the second function entity, where the second function entity is a device of the first communications system;

    a sending unit, configured to send a second request to the third function entity, where the second request includes the voice bearer information and an identifier of the target access network node, where the third functional entity is in the second communications system device of.
29. The first functional entity according to claim 28, wherein the second request is for requesting the third functional entity to send a third request to the target mobile switching center MSC, the target MSC serving the target An access network node, the third request for requesting to switch the voice session from the first communication system to the target communication system, the target MSC being a device in a target communication system.
30. The first functional entity according to claim 28, wherein the first request further includes session identification information, the session identification information includes a session identifier of the voice session, and the processing unit is specifically configured to:

    Determining, according to the session identification information, a session identifier of the voice session, and determining, according to the session identifier of the voice session, the second function entity.
31. The first functional entity according to claim 28, wherein the processing unit is specifically configured to:

    A second functional entity having voice conferencing support capability is determined from at least two second functional entities corresponding to all sessions of the UE.
32. The first functional entity according to claim 28, wherein the first request further includes session identification information, and the processing unit is specifically configured to:

    Determining, according to the session identification information carried in the first request, network slice selection assistance information NSSAI and/or data network name DNN;

    Determining, according to the NSSAI and/or the DNN, that the second functional entity corresponding to the NSSAI and/or the DNN has the voice session support capability;

    Determining the second functional entity.
33. The first functional entity according to any one of claims 28 to 32, wherein the first request further comprises session identification information, the session identification information includes a session identifier of the voice session, and the processing The unit is also specifically used to:

    Sending a fourth request to the second function entity, where the fourth request carries a session identifier of the voice session;

    And receiving the voice bearer information corresponding to the session identifier of the voice session sent by the second function entity.
34. The first functional entity according to any one of claims 28 to 32, wherein the first request further includes a voice switching indication, and the processing unit is further configured to:

    Sending a fifth request to the second function entity, where the fifth request carries the voice switching indication;

    Receiving, by the second functional entity, the voice bearer information sent according to the voice switching indication.
35. The first functional entity according to any one of claims 28 to 34, wherein the transmitting unit is specifically configured to:

    Obtaining a single radio frequency session transfer number STN-SR and a mobile station international subscriber identity code MSISDN;

    Sending the second request to the third functional entity, where the second request carries the STN-SR and the MSISDN.
36. The first functional entity according to any one of claims 28-35, wherein the identity of the target access network node comprises a target universal terrestrial radio access network identity or a target global mobile communication system and an evolved wireless connection Enter the GERAN logo.
37. The first functional entity according to claim 28, wherein the first functional entity further comprises:

    a determining unit, configured to determine the third functional entity according to the identifier of the preset third functional entity;

    or,

    Querying the domain name system DNS and/or the network storage function function entity NRF to obtain the identifier of the third functional entity;

    Determining the third functional entity according to the identifier of the third functional entity.
38. A radio access network device, comprising:

    a receiving unit, configured to receive a measurement report sent by the user equipment, where the radio access network device is a device of the first communication system;

    a sending unit, configured to send, according to the measurement report, a first request to the first functional entity, where the first request is used to request that the ongoing voice session of the user equipment UE is switched from the first communications system to the target communications system, The first functional entity is a device in the first communication system;

    The first request carries the session identifier information, where the session identifier information includes only the session identifier of the voice session, or the session identifier information includes a session identifier that carries a voice indication.
39. The radio access network device according to claim 38, wherein the first request is used to request the first functional entity to determine a second functional entity according to the session identifier, and obtain the second functional entity from the second functional entity. Voice bearer information of the voice session, which in turn switches the voice session from the first communication system to the target communication system by a third functional entity, the second functional entity being in the first communication system The device, the third functional entity is a device in the second communication system.
40. The radio access network device according to claim 38, wherein the radio access network device further comprises:

    And a first determining unit, configured to determine to switch the voice session from the first communications system to the target communications system according to at least the voice stream information of the UE or the voice data radio bearer information, and the measurement report.
41. The radio access network device according to claim 38, wherein the radio access network device further comprises:

    And a second determining unit, configured to determine a session identifier of the voice session according to at least the voice stream information of the UE or the voice data radio bearer information.
42. The radio access network device according to any one of claims 38 to 41, wherein the first request is for requesting to switch the voice session from the first communication system to the target communication system Circuit switched domain.
43. A computer readable storage medium comprising instructions which, when executed on a computer, cause the computer to perform the method of any of claims 1-21.
44. A computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of any of claims 1-21.

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