WO2010108420A1

WO2010108420A1 - Method, network system and interworking function entity for processing switch of communication service

Info

Publication number: WO2010108420A1
Application number: PCT/CN2010/071140
Authority: WO
Inventors: 陈中平; 吴问付
Original assignee: 华为技术有限公司
Priority date: 2009-03-27
Filing date: 2010-03-19
Publication date: 2010-09-30
Also published as: CN101848443A; CN101848443B

Abstract

A method, a network system and an interworking function entity for processing the switch of communication service are provided. The method includes: receiving a first register request message sent from a source network by a user equipment, and completing the register of the user equipment to a service interworking function (IWF) of the user equipment; receiving a second register request message sent from the source network by the user equipment, and sending the second register request message to a source service mobility management entity(MME) of the user equipment, so as to complete the register of the user equipment to the source service MME; receiving a switch request message of the user equipment in the source network, and forwarding the switch request message to the source service MME, so as to make the source service MME to perform a switch process to switch the user equipment into a target network.

Description

,

Functional entity

This application claims the priority of the Chinese application filed on March 27, 2009, with the application number 200910081004.6, and the invention name is "communication service switching processing method, network system and interworking function entity", the entire contents of which are incorporated herein by reference. In the application.

Technical field

The present invention relates to communication technologies, and more particularly to a communication service switching processing method, a network system, and an interworking function entity.

Background technique

Circuit Switched (CS) domain mainly deals with voice services. The signaling plane control entity of the CS domain is the Mobile Switch Center/Visitor Location Register (hereinafter referred to as MSC/VLR). GSM/Enhanced Data Rate GSM/EDGE Radio Access Network (hereinafter referred to as GERAN), Base Station Controller (BSC) and Base Station (Base Transceiver Station, hereinafter referred to as: BTS) is connected to the MSC through the A interface. In the Universal Mobile Telecommunications System (UMTS) UMTS Territorial Radio Access Network (hereinafter referred to as UTRAN), the Radio Network Controller (hereinafter referred to as RNC) and the base station (NodeB) is connected to the MSC through the Iu interface.

In order to meet the challenges of wireless broadband technology and maintain the leading edge of 3GPP networks, 3GPP developed the Long Term Evolution (LTE) program at the end of 2004. An evolved packet system (hereinafter referred to as EPS) is defined in the LTE plan. The EPS core network mainly includes a Mobility Management Entity (hereinafter referred to as MME), a Serving Gateway (hereinafter referred to as S-GW), and a Packet Data Network Gateway (hereinafter referred to as P-GW). Three logical functions. The MME is mainly used to implement access stratum (Access Stratum, hereinafter referred to as AS) signaling and non-access stratum (Non Access Stratum, hereinafter referred to as NAS) signaling encryption, roaming, and tracking. And assign user temporary IDs, security features, and more. The S-GW is mainly used to implement a local mobility anchor and a mobility anchor inside the 3GPP system, and to legally monitor related information functions. The P-GW is mainly used to implement policy enforcement and accounting, and to legally monitor related information functions.

With the development of communication technologies and the increasing demand for communication services, communication services often need to be in GERAN or UTRAN (hereinafter referred to as: GERAN/UTRAN) and the evolved universal mobile telecommunication system Terrestrial Radio Access Network (Evolved UMTS Terrestrial Radio Access Network, The following is referred to as: E-UTRAN). However, since the radio access network element evolved base station (Evolved NodeB, hereinafter referred to as eNB) in the existing E-UTRAN cannot process the CS domain signaling process, it is still impossible to implement GERAN/UTRAN to E-UTRAN CS. Domain service switching. Summary of the invention

The embodiments of the present invention provide a communication service switching processing method, a network system, and an interworking function entity, and implement handover of a CS domain service from GERAN/UTRAN to E-UTRAN.

A communication service switching processing method provided by an embodiment of the present invention includes:

Receiving a first registration request message sent by the user terminal on the source network, and completing registration of the service interworking function entity IWF of the user terminal to the user terminal;

Receiving a second registration request message sent by the user terminal on the source network, and sending the second registration request message to a source service mobility management entity MME of the user terminal, so that the user terminal completes to the source Registration of the service MME;

Receiving a handover request message of the user terminal in the source network, and forwarding the handover request message to the source serving MME, so that the source serving MME performs a handover procedure, and the user terminal is switched to a target network. .

An interworking function entity provided by the embodiment of the present invention includes:

a registration receiving unit, configured to receive a first registration request message sent by the user terminal on the source network, and complete registration of the user terminal to the user IWF of the user terminal;

a forwarding unit, configured to receive a second registration request message sent by the user terminal on the source network, and forward the second registration request message to a source service MME of the user terminal, so that Determining that the user terminal completes registration with the source service MME;

a handover triggering unit, configured to receive a handover request message of the user equipment in the source network, and forward the handover request message to the source serving MME, so that the source serving MME performs a handover procedure, where the user terminal is configured Switch to the target network.

A mobile switching center provided by an embodiment of the present invention includes:

a receiving unit, configured to receive a handover request message of the user terminal sent by the access network element of the source network, and a determining unit, configured to determine, according to the handover request message received by the receiving unit, the service interworking function entity IWF of the terminal;

a sending unit, configured to send the handover request message to the service determined by the determining unit

IWF.

A mobility management entity provided by an embodiment of the present invention includes:

a receiving unit, configured to receive a handover request message of the user terminal sent by the IWF of the user terminal, and a switching unit, configured to switch the user terminal from the source network to the target network.

A network system provided by an embodiment of the present invention includes an MSC, a service IWF of a user terminal, and a source service MME of a user terminal, where

The MSC is configured to receive a handover request message of the user terminal sent by the access network element of the source network, determine a service IWF of the user terminal according to the handover request message, and send the handover request message to the determining Service IWF;

The service IWF is configured to receive a first registration request message sent by the user terminal on the source network, complete registration of the user terminal to the service IWF of the user terminal, and receive the user terminal to send on the source network. a second registration request message, and forwarding the second registration request message to a source service MME of the user terminal, so that the user terminal completes registration with the source service MME; receiving the user terminal at the Determining a handover request message of the source network, and forwarding the handover request message to the source serving MME, so that the source serving MME performs a handover procedure, and the user terminal is switched to the target network;

The source service MME is configured to receive a handover request of the user terminal sent by the service IWF a message, switching the user terminal handover from the source network to the target network.

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. DRAWINGS

FIG. 1 is a schematic diagram of a networking structure of a GERAN, UTRAN, E-UTRAN, and EPS core network;

2a is a flowchart of an embodiment of a communication service switching processing method according to the present invention;

2b is a flowchart of another embodiment of a communication service handover processing method according to the present invention; FIG. 3 is a UE registered to a service IWF by the UE and registered to the source service by the service IWF;

Flowchart of an embodiment of the MME;

4 is a UE registered to a service IWF by the UE and registered to the source service by the service IWF

Flowchart of another embodiment of the MME;

5 is a flowchart of an embodiment of an MSC addressing a serving IWF of a UE and transmitting a handover request message;

6 is a flowchart of another embodiment of the MSC addressing a serving IWF of a UE and transmitting a handover request message;

7 is a flowchart of still another embodiment of the MSC addressing a serving IWF of a UE and transmitting a handover request message;

8 is a flowchart of another embodiment of a communication service switching processing method according to the present invention;

FIG. 9 is a flowchart of an embodiment of a service IWF sending a handover request message to a source serving MME according to the present invention.

10 is a schematic structural diagram of an IWF according to an embodiment of the present invention;

11 is a schematic structural diagram of an embodiment of an MSC according to the present invention;

12 is a schematic structural diagram of an MME according to an embodiment of the present invention;

FIG. 13 is a schematic structural diagram of an embodiment of a network system according to the present invention.

detailed description

Since many communication services provided by operators are running in the CS domain, in order to be in the LTE network. The existing CS service is provided, and the existing technology connects the EPS core network to the CS domain core network. As shown in FIG. 1 , it is a schematic diagram of a networking structure of an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) and an EPS core network of GERAN, UTRAN, and Evolved UMTS Terrestrial Radio Access Network (E-UTRAN). According to FIG. 1, a user equipment (User Equipment, hereinafter referred to as UE) is connected to an MSC of a CS core network through an Interworking Function (hereinafter referred to as IWF). The IWF has the ability to simulate the Iu-CS/A interface, and the protocol stack corresponding to the Iu-CS/A interface can be configured on the IWF. When the UE communicates with the MSC, it first sends a message to the IWF. After receiving the message sent by the UE, the IWF converts it into a signaling format on the Iu-CS/A interface, and sends it to the MSC, thereby completing communication between the UE and the MSC. Similarly, the IWF can forward the message sent by the MSC through the Iu-CS/A interface to the UE. Sv is a reference point between the MME and the IWF. When the LTE network switches to the GERAN/UTRAN, the MME generates a handover request message to the IWF through the Sv. Z1 is a reference point between the UE and the IWF, and can serve as an IP channel between the IWF and the UE.

2a is a flowchart of an embodiment of a communication service switching processing method according to the present invention, which includes:

51. Receive a first registration request message sent by the user terminal on the source network, and complete registration of the service interworking function entity IWF of the user terminal to the user terminal;

The second registration request message sent by the user terminal on the source network is received, and the second registration request message is sent to the source service mobility management entity MME of the user terminal, so that the user terminal completes the Describe the registration of the source service MME;

53. Receive a handover request message of the user equipment in the source network, and forward the handover request message to the source service MME, so that the source service MME performs a handover procedure, and the user terminal is switched to the target network.

The source network may be a network such as GERAN or UTRAN, and the target network may be an E-UTRAN or the like. In the method provided by the embodiment of the present invention, the UE may register to the serving IWF through the GERAN/UTRAN, and register with the source IMME through the serving IWF. When the CS domain service of the UE is switched from the GERAN/UTRAN network to the E-UTRAN, The MSC forwards the handover request message of the UE to the source serving MME by using a serving IWF, indicating the source serving MME The switching service of the CS domain is completed.

In the step S2, before the sending the second registration request message to the source service mobility management entity MME of the user terminal, the method may further include: determining a source service MME of the user terminal.

The communication service switching processing method provided by the embodiment of the present invention, the UE may register with the IWF through the GERAN/UTRAN, and register with the serving MME through the service IWF, so that the CS domain service of the subsequent UE needs to be switched from the GERAN/UTRAN to the E-UTRAN. The service IWF may serve as the target access network element in the E-UTRAN, and instruct the serving MME to perform the handover process of the CS domain service to the E-UTRAN according to the source service MME information stored in the process of the UE registration to the serving MME. The target access network element eNB in the E-UTRAN cannot handle the CS domain signaling process problem, and ensures the normal handover of the CS domain service from the GERAN/UTRAN to the E-UTRAN, thereby ensuring the quality of the communication service of the user.

FIG. 2b is a flowchart of another embodiment of a communication service switching processing method according to the present invention. As shown in FIG. 2b, the communication service switching processing method of this embodiment includes the following steps:

Step 101: The UE registers with the IWF through the GERAN/UTRAN, and registers with the MME of the UE through the service IWF. The IWF is the serving IWF of the UE, and the MME is the source service MME of the UE.

Step 102: The access network element of the GERAN/UTRAN forwards the handover request message of the UE to the MSC, where the handover request message includes the CS domain handover information and the target access network NE identifier (identifier, hereinafter referred to as ID) in the E-UTRAN )information.

Specifically, the access network element of the GERAN/UTRAN may specifically be a BSC or an RNC. The target access network element in the E-UTRAN may specifically be an eNB.

Step 103: The MSC addresses the serving IWF of the UE, and forwards the handover request message to the serving IWF. Step 104: The serving IWF instructs the source service MME to perform a handover procedure of the CS domain service to the E-UTRAN according to the source service MME information stored in the process of registering to the source serving MME by the serving IWF.

Step 105: After the UE accesses the E-UTRAN, the serving IWF sends a handover completion to the MSC. The message is informed so that the MSC delivers the traffic to the serving IWF and triggers the bearer setup procedure in the E-UTRAN so that the traffic is delivered to the UE through the serving IWF.

The UE can register with the IWF through the GERAN/UTRAN and register with the serving MME through the service IWF. Thus, when the CS domain service of the subsequent UE needs to be switched from GERAN/UTRAN to E-UTRAN, the service I WF can be used as the E-UTRAN. The target access network element, according to the source service MME information stored in the process of the UE registering to the serving MME, instructs the serving MME to perform the handover process of the CS domain service to the E-UTRAN, and solves the target access network in the E-UTRAN. The meta-eNB can not handle the CS domain signaling process problem, and ensures the normal handover of the CS domain service from GERAN/UTRAN to E-UTRAN, thus ensuring the quality of the communication service of the user.

The communication service switching processing method of the embodiment of the present invention can be applied to any communication service, especially a voice service. In the following embodiments of the present invention, the voice service is taken as an example for description, and the same applies to other services.

In step 101 of the embodiment shown in FIG. 2, the UE may register to the IWF through the GERAN/UTRAN in the following two manners, and register with the MME of the UE through the serving IWF: One is that the UE passes the GERAN/UTRAN The CS domain is registered to the serving IWF of the UE and registered to the source serving MME of the UE through the serving IWF. Specifically, after the UE completes the CS domain attachment, the UE may trigger the UE to register to the serving IWF of the UE through the CS domain of the GERAN/UTRAN, which is equivalent to the UE actively triggering the registration of the service IWFo to the UE. When performing network handover, the access network element of the GERAN/UTRAN may also notify the UE to register with the IWF. This is equivalent to the UE passively triggering the service IWF registered to the UE. The PS) domain is registered to the serving IWF of the UE and registered to the source service MME of the UE through the serving IWF. Specifically, after the UE completes the PS domain attachment, the UE may trigger the UE to register with the serving IWF of the UE through the PS domain of the GERAN/UTRAN, which is equivalent to the UE actively triggering the service IWF registered to the UE. In addition, when the UE wants to perform network handover, the access network element of the GERAN/UTRAN may also notify the UE to register with the IWF. This is equivalent to the UE passively triggering the service IWF registered to the UE. 3 is a flow chart of an embodiment in which a UE registers with a serving IWF and registers with the source IMME through the service IWF. In this embodiment, the UE registers with the serving IWF of the UE through the CS domain of the GERAN/UTRAN, and registers with the source serving MME of the UE through the serving IWF. Before the UE registers with the serving IWF, the channel between the UE and the serving IWF is established, so that the UE and the IWF perform signaling interaction or data interaction through the channel. According to an embodiment of the present invention, a UE may establish a USSD tunnel between the UE and its serving IWF by using an Unstructured Supplementary Service Data (hereinafter referred to as USSD). In the USSD mode, the IWF can be regarded as a USSD server. As shown in FIG. 3, the process of this embodiment specifically includes the following steps:

Step 201: The serving IWF receives a first registration request message sent by the UE through the USSD tunnel, for example: UE-IWF-RC REGISTER REQUEST. The first registration request message is sent by the UE to the serving IWF through the access network element BSC/RNC and the MSC of the GERAN/UTRAN, and is used to request registration to the service IWF. The first registration request message includes the user identifier and the UE in the GERAN. Current location information in /UTRAN. The user identifier may be an International Mobile Subscriber Identification Number (IMSI), and the current location information of the UE in the GERAN/UTRAN may be the current location area of the UE in the GERAN/UTRAN. Location Area Identity (LAI), Routing Area Identity (RAI) or Cell Global Identifier (CGI).

Step 202: The service IWF processes the first registration request message.

Step 203: The serving IWF returns a first registration accept message to the UE through the access network element BSC/RNC of the MSC and the GERAN/UTRAN, for example: UE-IWF-RC REGISTER ACCEPT.

Step 204: The serving IWF receives a second registration request message sent by the UE through the USSD tunnel, where the second registration request message is sent by the UE to the serving IWF through the access network element BSC/RNC and the MSC of the GERAN/UTRAN, for requesting Register to the source service MME, specifically can be attached The message Attach Request may also be a tracking area update request message TAU Request, which may be included in the message UE-IWF UL DIRECT TRANSFER in which the UE interacts with the serving IWF.

Step 205: The serving IWF selects a source serving MME for the UE, and forwards a second registration request message to the selected source serving MME. Specifically, if the second registration request message is included in the message UE-IWF UL DIRECT TRANSFER, the UE's IWF receives the message UE-IWF UL DIRECT TRANSFER, and then parses the UE to send the message. Second registration request message. The service IWF detects whether the MME information is included in the received second registration request message.

If the MME information is not included in the second registration request message, the service IWF selects an MME that meets the preset condition from the MME list as the source service MME according to a preset, and the MME list may be saved on the service IWF. According to the preset setting, the preset service IWF may arbitrarily select one MME as the source service MME in the MME list after receiving the second registration request message; or preset the service IWF to receive the second registration request message after receiving the second registration request message. Selecting a small-load MME as the source serving MME in the MME list; or selecting the source serving MME of the user terminal according to other policies preset.

If the MME information is included in the second registration request message, the service IWF queries whether the MME identified by the MME information included in the second registration request message exists in the pre-stored MME list. If it exists in the MME list, the serving IWF selects the MME identified by the MME information included in the second registration request message as the source serving MME. If it does not exist in the MME list, the serving IWF selects an MME that satisfies the preset condition from the MME list as the source serving MME according to the pre-set. When the MME information included in the second registration request message is not on the MME list, the process in which the serving IWF selects the source serving MME may refer to the processing when the MME information is not included in the second registration request message.

Specifically, the MME information may be a Globally Unique Temporary Identity (hereinafter referred to as GUTI) or an MME ID. Step 206: The source service MME processes the second registration request message, and returns a second registration accept message to the service IWF. The second registration accept message may be an attach accept message Attach Accept or a tracking area update accept message TAU. Accept.

Step 207: The serving IWF returns a second registration accept message to the UE through the MSC and the access network element BSC/RNC of the GERAN/UTRAN, and saves the source service MME information in the context of the UE, so as to serve in the subsequent process. The IWF addresses the source serving MME serving the UE. Specifically, the second registration accept message Attach Accept/TAU Accept may be included in the message UE-IWF DL DIRECT TRANSFER that the UE interacts with the serving IWF.

So far, the UE completes the registration to the IWF through GERAN/UTRAN, and then completes the registration to the MME through the service IWF.

In addition, in step 201, the serving IWF may further obtain the current cell information of the UE according to the first registration request message sent by the UE, that is, the current location information of the UE in the GERAN/UTRAN. Correspondingly, in step 204, after receiving the second registration request message sent by the UE, the service IWF may further perform the following operations: the service IWF converts the current location information of the UE into the location information of the E-UTRAN according to the preset conversion relationship. And transmitting the location information of the E-UTRAN to the source serving MME. Alternatively, the serving IWF uses the location information of the pre-configured E-UTRAN as the location information of the UE in the E-UTRAN, and sends it to the source serving MME for subsequent mobility association or session association procedure.

Since the channel between the UE and the serving IWF in the E-UTRAN network is IP, for the IWF, the IP address of the UE needs to be recorded, and by the embodiment shown in FIG. 3 above, between the UE and the serving IWF. The channel is a USSD tunnel and is non-IP. Therefore, after the UE completes the registration to the source service MME, it also needs to re-establish the IP channel of the UE to its serving IWF, and provide the IP address information to the IWF, that is, the UE re-registers with the service IWF in the EPS network, and passes the registration process. Provide IP address information to its service IWF. If the registration of the UE to its serving IWF has been previously performed in GERAN/UTRAN, the UE needs to perform deregistration at the GERAN/UTRAN to the serving IWF before performing the process of completing the registration to the serving IWF through the EPS network, and then initiates The process of completing the service IWF registration through the EPS network. At this time, its service IWF is the service IWF in the previous GERAN/UTRAN. That is, after the step 207 of the process shown in FIG. 3, the method further includes: the source service MME establishes an Internet Protocol IP channel of the UE to the IWF; and the service IWF receives the IP address information of the UE sent by the UE.

The source service MME establishes the Internet Protocol IP channel of the UE to the IWF. The source service MME receives the packet data network (Packet Data Network, PDN) connection request message (PDN Connectivity Request) sent by the UE. The access point name (APN Access Point Name, APN for short) information can be the default APN or other APN. The UE may initiate the PDN connection request in the process of attaching the network, or may initiate the PDN connection request after attaching the network;

The source service MME sends a default bearer request to the S-GW/P-GW. Create Default Bearer Request;

A bearer is created between the S-GW/P-GW and the source serving MME, and a default bearer response is created to the source service MME. Create Default Bearer Response;

The source service MME returns a PDN Connectivity Accept message to the UE PDN Connectivity Accept. The establishment process of the foregoing PDN connection is actually preparing the channel for performing the CS service in the EPS network in advance, and establishing the PDN connection is to establish an IP channel for the UE to the service IWF, and establishing the CS domain service in the EPS network through the above process. After the PDN is connected, the UE can implement signaling interaction or data interaction with the serving IWF through the IP channel, so that the UE can complete the registration to its serving IWF. In addition, the UE can also obtain the IP address of the subsequent CS domain service in the EPS network. . Conducive to the subsequent switching process.

The service IWF receives the IP address information of the UE sent by the UE, including:

The serving IWF receives a third registration request message sent by the UE through the IP channel, for example: UE-IWF-RC REGISTER REQUEST, where the third registration request message includes the IP address information of the UE;

The service IWF stores the IP address information of the UE, and returns a third registration accept message to the UE, for example. Such as: UE-IWF-RC REGISTER ACCEPT.

So far, the IP channel between the UE and its serving IWF in the EPS network has been pre-established.

The UE establishes an IP channel between the UE and the serving IWF through the packet exchange of the GERAN/UTRAN to the serving IWF, so that the UE and the IWF perform signaling interaction or data interaction through the IP channel. According to an embodiment of the present invention, a UE may establish a GPRS Tunneling Protocol (GTP) tunnel between the UE and its serving IWF as an IP channel between the UE and its serving IWF. As shown in Figure 4, a GTP tunnel can be established between the UE and its serving IWF by the following procedure:

Step 30A: The UE sends a PDP activation request message (Activate PDP Context Request) to the General Packet Radio Service Support Node (SGSN) through the access network element BSC/RNC of the GERAN/UTRAN. The APN information carried in the message may be the default APN or other APN.

Step 30B: The SGSN sends a Create PDP Context Request message to the S-GW/P-GW to create a bearer between the SGSN and the S-GW/P-GW.

Step 30C: Create a bearer between the S-GW/P-GW and the SGSN, and return a Create PDP Context Response message to the SGSN.

Step 30D: The SGSN returns a PDP activation accept message Activate PDP Context Accept to the UE through the access network element BSC/RNC of the GERAN/UTRAN.

4 is a flow chart of another embodiment of a UE registered to a serving IWF and registered to a source serving MME by the serving IWF. After establishing a GTP tunnel between the UE and its serving IWF, the UE registers with the serving IWF of the UE through the PS domain of the GERAN/UTRAN, and registers with the source serving MME of the UE through the serving IWF. As shown in FIG. 4, the process of this embodiment specifically includes the following steps: Step 301: The serving IWF receives a first registration request message sent by the UE through the GTP tunnel, for example, UE-IWF-RC REGISTER REQUEST. The first registration request message is sent by the UE to the serving IWF through the access network element BSC/RNC and SGSN of the GERAN/UTRAN, and is used to request registration to the service IWF. The first registration request message includes the user identifier and the UE. Current location information in GERAN/UTRAN. The user identifier may be an IMSI, and the current location information of the UE in the GERAN/UTRAN may be the current LAI, RAI, or CGI of the UE in the GERAN/UTRAN.

Step 302: The service IWF processes the first registration request message.

Step 303: The serving IWF returns the first registration accept message to the UE through the access network element BSC/RNC of the SGSN and the GERAN/UTRAN, for example: UE-IWF-RC REGISTER ACCEPT.

Step 304: The serving IWF receives a second registration request message sent by the UE through the GTP tunnel, and the second registration request message is sent by the UE to the serving IWF through the access network element BSC/RNC and SGSN of the GERAN/UTRAN in sequence for requesting. The registration to the source service, specifically the Attach Request message, or the Tracking Area Update Request message TAU Request, may be included in the message UE-IWF UL DIRECT TRANSFER that the UE interacts with the serving IWF.

Step 305: The serving IWF selects a source serving MME for the UE, and forwards a second registration request message to the selected source serving MME. Specifically, if the second registration request message is included in the message UE-IWF UL DIRECT TRANSFER, the UE's IWF receives the message UE-IWF UL DIRECT TRANSFER, and then parses the UE to send the message. Second registration request message.

Specifically, the method for the serving IWF to select the source serving MME for the UE may refer to step 205. Step 306: The source service MME processes the second registration request message, and returns a second registration accept message to the service IWF. The second registration accept message may be an attach accept message Attach Accept or a tracking area update accept message TAU. Accept.

Step 307: The serving IWF returns a second registration accept message to the UE through the access network element BSC/RNC of the SGSN and the GERAN/UTRAN, and saves the source service MME information in the context of the UE, so as to serve in the subsequent process. The IWF addresses the source serving MME serving the UE. Specifically, the second registration accept message Attach Accept/TAU Accept may be included in the message UE-IWF DL DIRECT TRANSFER in which the UE interacts with the serving IWF. So far, the UE completes the registration to the IWF through GERAN/UTRAN, and then completes the registration to the MME through the service IWF.

Since the GTP tunnel is already in the IP mode, through the process of the embodiment shown in FIG. 4, it is not necessary to re-establish the IP channel of the UE to its service IWF. Subsequent execution When the GERAN/UTRAN handovers to the E-UTRAN, the GERAN/UTRAN network synchronizes to the E-UTRAN network, that is, when the network handover is performed by the GERAN/UTRAN network to the E-UTRAN, the IP address of the UE does not change.

Through the foregoing process shown in FIG. 3 and FIG. 4, the UE completes the registration of the GERAN/UTRAN to the serving IWF, and then completes the registration to the source service MME through the service IWF, and the UE can be pre-established to the serving IWF through the source service MME. Channels, which can reduce the delay of subsequent CS domain service switching, improve communication quality and user service experience.

In the process of the UE completing the registration to the MME through the IWF, the serving IWF actually performs the interface function of the eNB, that is, the service IWF needs to configure the corresponding protocol stack of the S1 interface, so that the source service MME can communicate with the source service MME. After the UE completes the registration to the serving IWF through step 202 or step 302, the serving IWF may create a context of the UE for the UE. Therefore, in the step 104 of the embodiment shown in FIG. 2, when the serving IWF instructs the source serving MME to perform the handover procedure of the CS domain service to the E-UTRAN, the source serving MME and the target access network in the E-UTRAN need to be detected first. Whether to establish an S1 connection between the elements. If the S1 connection is established, the serving IWF directly instructs the source service MME to perform the handover process of the CS domain service to the E-UTRAN. If the S1 connection is not established, the serving IWF triggers the source service MME to establish an S1 connection with the target access network network element, and after the S1 connection is established, instructs the source service MME to perform the handover process of the CS domain service to the E-UTRAN.

In the prior art, when the CS domain handover occurs, the access network element BSC/RNC of the source GERAN/UTRAN reports only the target access network NE ID information to the source MSC. Therefore, for the CS domain handover, one of the processing difficulties of the prior art is how to ensure that the MSC can be associated with the serving IWF of the UE when the handover is performed, so that the MSC addresses the UE's serving IWF instead of the target in the E-UTRAN. The access network element eNB is closed. FIG. 5 is a service IWF of the MSC addressing UE according to the present invention; And a flowchart of an embodiment of transmitting a handover request message. As shown in FIG. 5, this embodiment includes the following steps:

Step 401: The access network element BSC/RNC of the GERAN/UTRAN receives the handover measurement report reported by the UE, where the handover measurement report includes measurement information of the E-UTRAN and measurement information of the service IWF registered by the UE.

In the embodiment of the present invention, when the UE reports the measurement report, the measurement information of the E-UTRAN and the measurement information of the IWF may be identified. The access network element can identify the measurement information of the E-UTAN reported by the UE and the measurement information of the IWF according to the identifier of the UE. The measurement information of the IWF is derived from the IWF system information provided by the registered IWF to the UE during the discovery and registration process of the UE performing the IWF.

Step 402: The access network element BSC/RNC of the GERAN/UTRAN sends a handover request message to the MSC according to the measurement information of the E-UTRAN and the measurement information of the service IWF registered by the UE, where the handover request message is included. Information related to the service IWF, and the related information of the service IWF corresponds to the measurement information of the service IWF.

Step 403: The MSC addresses the serving IWF of the UE according to the related information of the serving IWF, and sends a handover request message to the serving IWF.

Specifically, in step 401, the measurement information of the serving IWF may be the cell information of the serving IWF, for example: Absolute Radio Frequency Channel Number (ARFCN), base station identity code (hereinafter referred to as: BSIC), in step 403, the related information of the serving IWF is specifically the target identifier/target cell information of the serving IWF. Correspondingly, before step 402, the method further includes: the access network element of the GERAN/UTRAN mapping the cell information of the serving IWF to the cell global identifier CGI, and according to the correspondence between the preset CGI and the target identifier/target cell Information, obtaining target identifier/target cell information corresponding to the CGI. Step 403 is specifically as follows: The MSC addresses the serving IWF of the UE according to the target identifier of the serving IWF/corresponding relationship information between the target cell and the IWF.

The measurement information of the service IWF and the information about the service IWF may also be specific to the address information of the service IWF, for example: serial number. Correspondingly, in step 403, the MSC addresses the address of the serving IWF. The domain name system (DNS) is parsed to obtain the address of the service IWF, and the address addressing service IWF of the service IWF is located.

6 is a flow chart showing another embodiment of the MSC addressing the serving IWF of the UE and transmitting a handover request message. In this embodiment, the serving IWF of the UE registers itself in the Home Subscriber Server (hereinafter referred to as HSS). When the network handover occurs, the MSC finds that the target network of the UE handover is E-UTRAN, and requests the IWF from the HSS. Address information. As shown in Figure 6, this embodiment includes the following steps:

Step 501: The serving IWF receives a first registration request message sent by the UE, for example: UE-IWF REGISTER REQUEST.

Step 502: The serving IWF sends a fourth registration request message to the HSS of the UE, for example, the Update Location Requests message includes the information about the service IWF, for example: an IWF ID, according to which the IWF ID can be addressed. IWF. In addition, the fourth registration request message further includes the IMSI of the UE user.

Step 503: The HSS registers the service IWF and returns a fourth registration response message to the service IWF.

Step 504: The serving IWF returns a fourth registration response message to the UE, for example: GA-RC REGISTER ACCEPT, and the registration response message includes the IWF information.

Step 505: The UE switches the measurement report to the access network element BSC/RNC of the GERAN/UTRAN.

Step 506: The access network element BSC/RNC of the GERAN/UTRAN sends a handover request message to the MSC, for example: Handover CS to VoIP bearer.

Step 507: The MSC sends an IWF address request message to the HSS, for example, an IWF Request, where the MSC ID of the MSC and the IMSI of the UE user are requested by the HSS to request the UE to register the IWF address information.

Step 508: The HSS returns an IWF address response message to the MSC, for example, an IWF Response (IMF ID, IMSI), and returns the IWF address information registered by the UE to the MSC. Step 509: The MSC addresses the serving IWF of the UE according to the correspondence information between the related information of the serving IWF and the IWF, and sends a handover request message to the serving IWF.

Figure 7 is a flow chart showing still another embodiment of the MSC addressing the serving IWF of the UE and transmitting the handover request message. In this embodiment, the IWF registers itself with the HSS, and the HSS can actively insert the IWF address as the subscription information to the MSC. As shown in FIG. 7, the embodiment includes the following steps: Step 601: The serving IWF receives a first registration request message sent by the UE, for example, UE-IWF REGISTER REQUEST.

Step 602: The serving IWF sends a fourth registration request message to the HSS of the UE, for example: Update Location Requests The fourth registration request message includes related information of the service IWF, for example: an IWF ID, according to which the corresponding IWF can be addressed. . In addition, the fourth registration request message further includes an IMSI of the UE user.

Step 603: The HSS registers the service IWF and returns a registration response message to the service IWF. Step 604: The serving IWF returns a registration response message to the UE, for example: GA-RC REGISTER ACCEPT, and the registration response message includes the IWF information.

Step 605: The HSS inserts the subscription data of the UE into the MSC when the related information of the serving IWF is updated, and the subscription data includes related information of the updated service IWF.

The IWF information can be used as the subscription data of the UE. When the HSS finds that the subscription data is changed, that is, the IWF information is updated, for example, in step 602, when the service IWF sends the registration request message, the HSS sends the registration element to the network element of the serving UE that has completed registration. For example: MSC, the insertion subscription data carries the associated IWF address information.

Step 606: The MSC returns a response message to the HSS.

The steps 605-606 and the steps 603-604 may not be performed in the above-mentioned time sequence, and the steps 605-606 may also be performed simultaneously with or before the steps 603-604.

Step 607: The MSC addresses the service IWF of the UE corresponding to the related information of the updated service IWF according to the correspondence information between the related information of the serving IWF and the IWF.

The step 607 can also be performed simultaneously with or before step 606. FIG. 8 is a flowchart of another embodiment of a communication service switching processing method according to the present invention. The communication service switching processing method in this embodiment is described by taking a voice service as an example, and is still applicable to other services. As shown in Figure 8, it includes the following steps:

Step 701: The UE registers with the IWF through the GERAN/UTRAN, and registers with the MME of the UE through the service IWF. The IWF is the serving IWF of the UE, and the MME is the source service MME of the UE.

Specifically, the step 701 can be implemented by the process of the embodiment shown in FIG. 3 or FIG. 4.

Step 702: The UE switches the measurement report to the access network element BSC/RNC of the GERAN/UTRAN, that is, the source access network element BSC/RNC, and the measurement report includes the measurement of the E-UTRAN. Information and measurement information of the service IWF registered by the UE.

Step 703: The source access network element BSC/RNC initiates a handover procedure according to the measurement information of the E-UTRAN and the measurement information of the service IWF registered by the UE.

Step 704: The source access network element BSC/RNC sends a handover request message Handover Required to the MSC to notify the MSC to perform CS domain handover.

Step 705: The MSC addresses the serving IWF of the UE, uses it as the target access network element, and sends a handover request message to the serving IWF. The Handover Request notifies the service IWF to prepare the resource. The handover request message includes CS domain handover information and target access network NE ID information in the E-UTRAN.

Step 706: The serving IWF learns that the target network to be switched is the E-UTRAN according to the target access network element ID, and sends a handover request message Handover Required ₀ according to the source service MME information of the previously recorded UE.

According to an embodiment of the present invention, when the serving IWF sends a handover request message to the source serving MME, if the UE does not establish a signaling connection S1 connection between the eNB and the source serving MME in the E-UTRAN network, the serving IWF first triggers The S1 connection establishment process establishes an S1 connection, and then sends a handover request message to the source service MME.

Step 707: The source serving MME sends a Forward Reset Request message Forward Relocation Request to the target MME, and delivers the context of the UE to the target MME. Step 708: According to related information such as the location of the UE and related information of the load and energy of the previously served S-GW, if the previously served S-GW cannot continue to serve, the target MME reselects the S-GW, and selects the S-GW. GW sends Create Bearer Request to create a bearer request message.

Step 709: The selected S-GW returns a Create Bearer Response message to the target MME, and establishes a bearer with the target MME.

Step 710: The target MME sends a handover request message to the target eNB in the E-UTRAN. Handover Requests

Step 711: The target eNB returns a handover request acknowledgement message to the target MME. Handover Request

Ack ₀

During the interaction between the target MME and the target eNB in step 710-711, the target MME further informs the eNB to establish a bearer according to the UE context transmitted by the source serving MME.

Step 712: The target MME replies to the source service MME by forwarding a reset response message Forward Relocation Response, and notifies the target network that the handover preparation phase in the E-UTRAN is completed.

Step 713: The source service MME sends a handover command Handover Command to the serving IWF to notify the target network that the handover preparation phase in the E-UTRAN is completed.

Step 714: The serving IWF completes resource preparation between the serving IWF and the MSC, and returns a handover request acknowledgement message Handover Ack to the MSC.

Step 715: The MSC returns a handover command Handover Command to the source access network element BSC/RNC to notify the completion of the handover preparation phase.

Step 716: The source access network element BSC/RNC sends a handover command Handover Command to the UE, and notifies the UE to switch to the target network. The handover command message carries related information of the target network E-UTRAN.

Step 717: The UE performs an E-UTRAN network access procedure according to the related information of the target network E-UTRAN, and then sends a handover complete message Handover Complete to the target access network element eNB.

Step 718: The target access network element eNB sends a handover complete notification message to the target MME. Handover Notify.

Step 719: The target MME sends a Forward Reset Complete message to the source serving MME, Forward Relocation Complete, to notify the source service MME that the UE has accessed the E-UTRAN.

Step 720: The source service MME returns a Forward Reset Complete Confirmation message Forward Relocation Complete Ack: to the target MME.

Step 721: The target MME sends an update bearer request message to the S-GW. Update Bearer Requestc

Step 722: The S-GW sends an update bearer request message Update Dedicated Bearer Request to the P-GW.

Step 723: The P-GW and the S-GW update the bearer, and return an update bearer response message Update Dedicated Bearer Response to the S-GW.

Step 724: The S-GW returns an update bearer response message to the target MME. Update Dedicated Bearer Response

Step 725: The UE initiates a tracking area update process TAU Procedure, and completes registration of the target MME to the HSS.

Step 726: The UE returns a handover complete message Handover Complete to the service IWF.

Step 727: The service IWF returns a handover complete message Handover Complete to the MSC, and the voice service flow is switched from the source side to the service IWF, that is, the MSC delivers the voice service flow to the service IWF.

Step 728: The service IWF triggers a bearer establishment process of the voice service flow.

Step 729: The service IWF provides a voice service related information to the Policy and Charging Rules Function (PCRF), and triggers the PCRF to initiate a Dedicated Bearer Activation Procedure for the voice service. The PCRF provides policy and charging control (PCC) information to the P-GW, and the P-GW initiates a dedicated bearer establishment process. The dedicated bearer is established, and the voice service flow is switched from the CS domain of the GERAN/UTRAN. To E-UTRAN.

In the embodiment shown in FIG. 2 to FIG. 8 of the present invention, the handover of the CS domain service is mainly handled. in case At the same time as the CS domain service handover, there is also an ongoing PS domain service that needs to be handed over from GERAN/UTRAN to E-UTRAN, that is, the handover of the CS domain and the PS domain service to the E-UTRAN in the GERAN/UTRAN is completed. According to the embodiment shown in FIG. 2 to FIG. 8 , the ongoing PS domain service can be cut off or suspended, that is, the smooth handover of the CS domain service is preferentially ensured.

According to another embodiment of the present invention, if both the CS domain service and the PS domain service need to be handed over from the GERAN/UTRAN to the E-UTRAN, in the step 102 of the embodiment shown in FIG. 2b, the handover request message is further The SGSN address information or the trigger information is used to trigger the source serving MME to acquire the context of the UE from the SGSN. The corresponding service flows are CS domain traffic and PS domain traffic. Since the access network element of the GERAN/UTRAN sends a handover request only to the MSC without transmitting a handover request to the SGSN, when the target network of the access network element of the GERAN/UTRAN perceives the handover is E-UTRAN, only the CS domain is triggered. Switch. In the subsequent steps 103 and 104, the MSC and the serving IWF do not parse the PS domain switching information, and are mainly delivered to the source serving MME through the serving IWF. Correspondingly, in step 104, when the source service MME is instructed to perform the handover process of the CS domain service to the E-UTRAN, the method further includes: indicating that the source service MME performs a handover process of the PS domain service to the E-UTRAN.

Specifically, the procedure for indicating that the source serving MME performs the handover of the PS domain service to the E-UTRAN includes: the serving IWF forwarding the handover request message to the source serving MME; the source serving MME addressing the SGSN, and acquiring the SGSN according to the SGSN address information or the trigger information The context of the UE; the source serving MME performs a handover procedure of the PS domain service to the E-UTRAN.

In addition, if the source serving MME does not have the SGSN address information registered by the UE, and before acquiring the context of the UE from the SGSN according to the trigger information, the method may further include: the serving IWF acquires the SGSN address information registered by the UE, and provides the SGSN address information to the source. Or the source MME obtains the SGSN address information registered by the UE from the HSS. Alternatively, the UE sends the SGSN address information registered by the UE to the source serving MME through the NAS signaling. The NAS signaling is specifically an attach request message, a TAU request message, or a PDN connection request message.

Specifically, the service IWF obtains the SGSN address information registered by the UE, where the UE may be: In the information exchange process of the IWF, the SGSN address information is sent to the serving IWF; or the UE receives the packet Temporary Mobile Subscriber Identity (P-TMSI) and the routing area identifier (hereinafter referred to as P-TMSI) re-allocated by the SGSN. When the Routing Area Identity (hereinafter referred to as RAI) is used, the SGSN address information is sent to the serving IWF.

FIG. 9 is a flowchart of an embodiment of a service IWF sending a handover request message to a source serving MME according to the present invention. As shown in FIG. 9, this embodiment includes the following steps:

Step 801: The serving IWF sends a handover request message to the source serving MME, where the handover request message includes CS domain handover information, PS domain handover information, target access network element ID information in the E-UTRAN, and SGSN address information registered by the UE. Or the trigger information, the SGSN address information or the trigger information is used to trigger the source serving MME to acquire the context of the UE from the SGSN.

Step 802: The source service MME addresses the serving SGSN of the UE, and sends a UE context request message Context Request to the serving SGSN to request the context of the UE.

Step 803: The serving SGSN returns a UE context response message Context Response to the source serving MME, where the context of the UE is included.

Step 804: The source serving MME returns a UE context confirmation message Context Ack to the serving SGSN. Specifically, in step 802, the source serving MME may address the serving SGSN of the UE in the following three ways:

The first way is: the serving IWF obtains the SGSN address information registered by the UE, and provides the SGSN address information to the source service MME. The UE may provide the registered SGSN address information to the IWF during the interaction with the IWF.

As an embodiment, in a process in which the UE registers with the IWF or registers an update, for example, the UE first registers with the IWF or the service IWF changes, and the UE re-registers to the new IWF, the UE may initiate the registration process to the IWF- The IWF DISCOVERY REQUEST message or the UE-IWF REGISTER REQUEST message or the UE-IWF REGISTER UPDATE UPLINK message carries the SGSN address information. Or, in the other interaction process between the UE and the IWF, the SGSN address information is carried in the related message and sent to the IWF. As another embodiment, if the UE has already registered to the serving IWF, if the UE receives the P-TMSI and RAI information re-allocated by the SGSN, for example: when the SGSN changes, the UE sends a message, for example: UE-IWF REGISTER UPDATE UPLINK, to the service The IWF, the message carries the updated SGSN address information. That is, each time the UE performs RAU in GERAN/UTRAN, the UE provides SGSN address information P-TMSI and RAI information to the serving IWF.

As a further embodiment, the UE may also use the service IWF as a destination instead of the signaling interaction, and place the SGSN address information in a data packet and deliver it to the service IWF. The IWF parses the packet to obtain the service SGSN address information.

The second mode is: When the source service MME needs to obtain the SGSN address information registered by the UE, the source service MME obtains the SGSN address information registered by the UE from the HSS.

Specifically, the source serving MME may send an SGSN address request message SGSN Request to the HSS, requesting to acquire the SGSN address information registered by the UE. The SGSN address request message includes the source service MME ID and the IMSI of the UE user. After receiving the SGSN address request message, the HSS returns an SGSN address response message SGSN Response to the source service MME, and returns the SGSN address information registered by the UE, including the SGSN ID and the IMSI of the UE user.

The third mode is: the UE sends the SGSN address information registered by the UE to the source serving MME through the NAS signaling. The NAS signaling is specifically an attach request message, an attach request message, a TAU request message, a PDN connection request message, a PDN Connectivity Request, and the like. In addition, the SGSN address information registered by the UE can also be transmitted by adding a new NAS message. If the UE receives the P-TMSI and RAI information re-allocated by the SGSN, for example, the SGSN changes, the UE may send the updated SGSN address information to the source service MME in the NAS message. That is, the UE provides the SGSN address information P-TMSI and RAI information to the source serving MME each time the UE performs the RAU in the GERAN/UTRAN.

FIG. 10 is a schematic structural view of an IWF according to an embodiment of the present invention. The IWF of this embodiment can serve as the serving IWF of the UE, and implement the corresponding functions of the serving IWF in the foregoing embodiment of the present invention. As shown in FIG. 10, the IWF of this embodiment includes a registration receiving unit 901, a forwarding unit 902, and a handover trigger unit. 903 and so on.

The registration receiving unit 901 is configured to receive a first registration request message sent by the user terminal on the source network, and complete registration of the user terminal to the monthly service IWF of the user terminal;

The forwarding unit 902 is configured to receive a second registration request message sent by the user terminal on the source network, and forward the second registration request message to the source service MME of the user terminal, so that the user terminal completes Registration of the source service MME;

The handover triggering unit 903 is configured to receive a handover request message of the user terminal in the source network, and forward the handover request message to the source serving MME, so that the source serving MME performs a handover procedure, and the user terminal is configured to Switch to the target network.

In another embodiment of the present invention, the forwarding unit 902 is further configured to determine that the source serving MME of the user terminal selects from the MME list when the second registration request message does not include the MME information. a preset condition MME as the source serving MME; or

When the MME information is included in the second registration request message, query whether the MME identified by the MME information included in the second registration request message exists in the MME list; if it exists in the MME list, Determining, by the MME list, an MME that is identified by the MME information included in the second registration request message, and selecting, as the source serving MME, an MME that meets a preset condition from the MME list. . The MME list can be saved on the service IWF.

In another embodiment of the present invention, the service IWF may further include:

The registration requesting unit is further configured to send a fourth registration request message to the home subscriber server HSS of the user terminal after the registration receiving unit completes registration of the user terminal, requesting completion of registration to the HSS.

In the above embodiment, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN or the like. The UE can register with the IWF through the GERAN/UTRAN and register with the serving MME through the service IWF. Thus, when the CS domain service of the UE needs to be handed over from the GERAN/UTRAN to the E-UTRAN, the serving IWF can be used as a target in the E-UTRAN. Network access network, according to UE The source service MME information stored in the process of registering to the serving MME indicates that the serving MME performs the handover procedure of the CS domain service to the E-UTRAN, and solves the problem that the target access network element eNB in the E-UTRAN cannot process the CS domain signaling process. The problem is to ensure the normal operation of the CS domain service switching from the GERAN/UTRAN to the E-UTRAN, thereby ensuring the quality of the communication service of the user.

FIG. 11 is a schematic structural diagram of an MSC according to an embodiment of the present invention, which includes a receiving unit 1001, a determining unit 1002, and a sending unit 1003, where:

The receiving unit 1001, the user terminal switching request cancellation determining unit 1002 for receiving the access network element of the source network, configured to determine the service interworking function entity IWF of the terminal according to the handover request message received by the receiving unit 1001;

The sending unit 1003 is configured to send the handover request message to the service IWF determined by the determining unit 1002.

In another embodiment of the present invention, when the handover request message includes related information of the serving IWF, the determining unit 1002, after receiving, by the receiving unit, the user terminal handover request message sent by the access network element, Querying the address of the service IWF to the HSS according to the information about the service IWF; or

When the related information of the serving IWF is updated, the HSS sends the subscription data including the related information of the serving IWF to the mobile switching center MSC, where the determining unit 1002 receives the user sent by the access network element at the receiving unit. After the terminal handover request message, determining the monthly service IWF of the user terminal is determined according to the related information of the service IWF.

In the above embodiment, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN or the like. The MSC provided by the embodiment of the present invention can forward the handover request of the user terminal in the source network to the service IWF, and solve the problem that the target access network element eNB in the E-UTRAN cannot process the CS domain signaling process, and the problem is ensured. The normal handover of the CS domain service from the GERAN/UTRAN to the E-UTRAN ensures the quality of the communication service of the user.

FIG. 12 is a schematic structural diagram of an MME according to an embodiment of the present invention, including a receiving unit 1101 And switching unit 1102, wherein:

The receiving unit 1101 is configured to receive a handover request message of the user terminal sent by the service interworking function entity IWF of the user terminal;

The switching unit 1002 is configured to switch the user terminal from the source network to the target network.

In another embodiment of the present invention, the mobility management entity further includes:

The first establishing unit is configured to establish an internet protocol IP channel of the user terminal to the interworking function entity IWF.

In addition, in another embodiment of the present invention, the mobility management entity further includes: a second establishing unit, configured to determine that an S1 connection is not established between the source serving MME and the target access network network element Establishing an S1 connection with the target access network element.

And an obtaining unit, configured to obtain address information of the general packet radio service support node SGSN, and obtain the context of the terminal user from the SGSN.

In the above embodiment, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN or the like. The mobility management entity provided by the embodiment of the present invention can receive the handover indication sent by the serving IWF in the source network, and switch the service of the user terminal from the source network to the target network, and solve the target access network element in the E-UTRAN. The eNB is unable to handle the problem of the CS domain signaling process, and ensures the normal handover of the CS domain service from the GERAN/UTRAN to the E-UTRAN, thereby ensuring the quality of the communication service of the user.

13 is a schematic structural diagram of an embodiment of a network system according to the present invention, which includes a mobile switching center MSC 1201, a service interworking function entity IWF 1202 of a user terminal, and a source service mobility management entity 1203 of a user terminal, where

The MSC 1201 is configured to receive a handover request message of the user terminal sent by the access network element of the source network, determine the service IWF 1202 of the terminal according to the handover request message, and send the handover request message to the determined Service IWF1202;

The service IWF 1202 is configured to receive a first registration request sent by the user terminal on the source network. And completing registration of the user terminal to the monthly service IWF 1202 of the user terminal; receiving a second registration request message sent by the user terminal on the source network, and forwarding the second registration request message to the source Serving the MME 1203, so that the user terminal completes registration with the source service MME 1203; receives a handover request message of the user terminal in the source network, and forwards the handover request message to the source service MME 1203, so that the The source service MME 1203 performs a handover procedure, and switches the user terminal to the target network.

The source service MME 1203 is configured to receive a handover request message of the user terminal sent by the service IWF 1202, and switch the user terminal handover from the source network to the target network.

In addition, the serving IWF 1202 is further configured to determine a source service MME of the user terminal. In another embodiment of the present invention, when the handover request message includes a CS domain service, the service IWF determines that an S1 connection is not established between the source service MME and the target access network network element. The serving IWF triggers the source serving MME to establish an S1 connection with the target access network network element.

In the above embodiment, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN or the like. The UE can register with the IWF through the GERAN/UTRAN and register with the serving MME through the service IWF. Thus, when the CS domain service of the UE needs to be handed over from the GERAN/UTRAN to the E-UTRAN, the serving IWF can be used as a target in the E-UTRAN. The network access network element, according to the source service MME information stored in the process of the UE registering to the serving MME, instructs the serving MME to perform the handover procedure of the CS domain service to the E-UTRAN, and solves the target access network element eNB in the E-UTRAN. The problem of the CS domain signaling process cannot be handled, and the normal handover of the CS domain service from the GERAN/UTRAN to the E-UTRAN is ensured, thereby ensuring the quality of the communication service of the user.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk. The embodiment of the present invention provides a method for processing a communication service, in particular a voice service, from a CS domain of a GERAN/UTRAN to an E-UTRAN. After the user attaches to the GERAN/UTRAN, and completes the registration to the IWF through the GERAN/UTRAN, the subsequent When a network switchover occurs, the IWF acts as the target access network element to process the handover process, which solves the problem that the eNB cannot process the CS domain signaling process, and ensures the normal handover of the GE domain from the GERAN/UTRAN to the E-UTRAN, ensuring communication. Quality and user experience. Further, the UE may also complete the registration to the MME through the serving IWF and pre-establish the transmission channel between the UE and the IWF through the MME. In the subsequent handover process, since the transport channel between the UE and the IWF has been established before, the serving IWF can smoothly transmit the CS domain service flow to the UE after receiving the CS domain service flow transmitted by the MSC, without performing execution. The process of attaching to the EPS network and establishing a transmission channel between the UE and the IWF in the EPS network reduces the delay of the CS domain service switching, and improves the communication quality and the user's service experience.

It should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention and are not to be construed as limiting. Although the present invention has been described in detail with reference to the preferred embodiments thereof, those skilled in the art will understand that the invention may be modified or equivalently substituted without departing from the teachings of the present invention. The spirit and scope of the programme.

Claims

Claim

A communication service switching processing method, comprising:

Receiving a first registration request message sent by the user terminal on the source network, completing registration of the user terminal to the service interworking function entity IWF of the user terminal;

The method according to claim 1, wherein before the sending the second registration request message to the source service mobility management entity MME of the user terminal, the method further includes:

Determining a source service MME of the user terminal.

The method according to claim 2, wherein the determining the source service MME of the user terminal comprises:

If the MME information is not included in the second registration request message, the serving IWF selects an MME that meets a preset condition from the MME list as the source service MME; or

If the second registration request message includes the MME information, the serving IWF queries whether the MME identified by the MME information included in the second registration request message exists in the MME list; if it exists in the MME list, The serving IWF selects an MME that is identified by the MME information included in the second registration request message as the source serving MME; or if it does not exist in the MME list, the serving IWF selects a preset from the MME list. a conditional MME as the source serving MME;

The MME list is saved on the service IWF.

The method according to claim 1, wherein if the second registration request message is sent to the service IWF through an unstructured supplementary data service USSD tunnel, the second note is After forwarding the book request message to the source service MME, the method further includes:

The source service MME establishes an internet protocol IP channel of the user terminal to the service IWF; the service IWF receives a third registration request message sent by the user terminal through the IP channel, and the service IWF stores the third The IP address information contained in the request message.

The method according to claim 1, wherein the receiving the handover request message of the user terminal in the source network comprises:

The user terminal sends the handover request message to the mobile switching center MSC through the access network element of the source network, and the MSC determines the service IWF of the user terminal according to the handover request message, and sends the handover request Give the service IWFo

The method according to claim 5, wherein the access network element of the source network sends the handover request message to the MSC, including:

The access network element receives the measurement report of the user terminal, where the measurement includes the measurement information of the target network and the measurement information of the service IWF registered by the user terminal;

And the access network element sends a handover request message to the MSC according to the measurement report of the user terminal, where the handover request message includes related information of the service IWF.

The method according to claim 6, wherein when the related information of the serving IWF is the target identifier or the target cell information of the serving IWF, and the measurement information of the serving IWF is the cell information of the serving IWF, the MSC Determining the service IWF of the user terminal according to the handover request message, including:

The access network element maps the cell information of the serving IWF to a cell global identifier CGI, and acquires a target identifier corresponding to the CGI according to the correspondence information between the preset CGI and the target identifier/target cell. / target cell information, and the target identifier / target cell information corresponding to the CGI is sent to the MSC;

The MSC determines, according to the correspondence information between the target identifier/target cell and the IWF, the service IWF of the user terminal corresponding to the CGI.

8. The method according to claim 5, wherein the receiving user terminal is in a source network The sending the first registration request message includes: the service IWF receiving the first registration request message sent by the user terminal;

After the serving IWF receives the first registration request message sent by the user terminal, the method further includes: sending, by the serving IWF, a fourth registration request message to the home subscriber server HSS of the user terminal, requesting completion of registration to the HSS.

The method according to claim 8, wherein the determining, by the MSC, the service IWF of the user terminal according to the handover request message, includes:

After receiving the user terminal handover request message sent by the access network element, the MSC obtains the address of the service IWF from the HSS according to the related information of the service IWF; or

The HSS inserts subscription data of the user terminal to the MSC when the related information of the serving IWF is updated, the subscription data includes related information of the updated service IWF, and the MSC receives the access network. After the user terminal switching request message sent by the element, the service IWF of the user terminal is determined according to the related information of the service IWF.

The method according to claim 1, wherein when the handover request message includes circuit switched domain service information, the method further includes:

When the S1 connection is not established between the source serving MME and the access network element of the target network, the serving IWF triggers the source service MME to establish an access network element with the target network. S1 connection.

The method according to any one of claims 1 to 10, wherein, when the handover request message includes packet domain service information, forwarding the handover request message to the source serving MME, so that The process of performing the handover by the source serving MME includes:

Receiving, by the source service MME, a handover request message forwarded by the service IWF;

Obtaining the address information of the general packet radio service support node SGSN, and acquiring the context of the user terminal from the SGSN, performing a handover process of the packet domain service.

The method of claim 11, wherein the obtaining the address information of the SGSN comprises: The serving IWF obtains SGSN address information registered by the user terminal, and provides the SGSN address information to the source serving MME; or

The source service MME obtains the SGSN address information registered by the user terminal from the HSS; or the user terminal sends the SGSN address information registered by the user terminal to the source service MME by using non-access stratum NAS signaling.

13. An interworking functional entity, comprising:

a registration receiving unit, configured to receive a first registration request message sent by the user terminal on the source network, to complete registration of the user terminal to the service IWF of the user terminal;

a forwarding unit, configured to receive a second registration request message sent by the user terminal on the source network, and forward the second registration request message to a source serving MME of the user terminal, so that the user terminal completes Registration to the source service MME;

a handover triggering unit, configured to receive a handover request message of the user terminal in the source network, and forward the handover request message to the source serving MME, so that the source serving MME performs a handover procedure, and the user terminal is configured to Switch to the target network.

14. The interworking functional entity of claim 13 wherein:

The forwarding unit is further configured to determine a source serving MME of the user terminal, and when the MME information is not included in the second registration request message, select an MME that meets a preset condition from the MME list as the source serving MME. ; or

When the MME information is included in the second registration request message, query whether the MME identified by the MME information included in the second registration request message exists in the MME list; if it exists in the MME list, And selecting, as the source service MME, the MME that is identified by the MME information included in the second registration request message, and the MME that meets the preset condition, as the source service MME, if not present in the MME list. ; wherein the MME list is saved on the service IWF.

The interworking function entity according to claim 13, further comprising: a registration requesting unit, configured to send, after the registration receiving unit completes registration of the user terminal, Sending a fourth registration request message to the home subscriber server HSS of the user terminal, requesting completion of registration to the HSS.

16. A mobile switching center, comprising:

a receiving unit, configured to receive a handover request message of the user terminal sent by the access network element of the source network; the determining unit, configured to determine, according to the handover request message received by the receiving unit, the service interworking function entity IWF of the terminal;

And a sending unit, configured to send the handover request message to the service IWF determined by the determining unit.

The mobile switching center according to claim 16, wherein when the handover request message includes related information of the serving IWF, the determining unit receives the access network element transmission at the receiving unit After switching the request message, querying the HSS for the address of the service IWF according to the related information of the service IWF; or

When the related information of the serving IWF is updated, the HSS sends the subscription data including the related information of the serving IWF to the MSC, where the determining unit receives the handover sent by the access network element in the receiving unit. After requesting the message, determining the service IWF of the user terminal is determined according to the related information of the service IWF.

18. A mobility management entity, comprising:

The mobility management entity according to claim 18, further comprising: a first establishing unit, configured to establish an IP channel of the user terminal to the IWF.

The mobility management entity according to claim 18, further comprising: a second establishing unit, configured to not establish an S1 connection between the source serving MME and the target access network element in the target network And establishing an S1 connection with the target access network element.

The mobility management entity according to any one of claims 18 to 20, further comprising:

An obtaining unit, configured to acquire address information of the SGSN, and obtain the user from the SGSN The context of the terminal.

22. A network system, comprising: an MSC, a serving IWF of a user terminal, and a source service MME of a user terminal, wherein

The service IWF is configured to receive a first registration request message sent by the user terminal on the source network, complete registration of the user terminal to the service IWF of the user terminal, and receive the user terminal to send on the source network. a second registration request message, and forwarding the second registration request message to a source service MME of the user terminal, so that the user terminal completes registration with the source service MME; receiving the user terminal at the Determining a handover request message of the source network, and forwarding the handover request message to the source-month service MME;

And the source service MME is configured to receive a handover request message of the user terminal sent by the service IWF, and switch the user terminal handover from the source network to the target network.