CN101848443B

Movatterモバイル変換

Info

Publication number: CN101848443B
Application number: CN200910081004.6A
Authority: CN
Inventors: 陈中平; 吴问付
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2009-03-27
Filing date: 2009-03-27
Publication date: 2014-01-01
Anticipated expiration: 2029-03-27
Also published as: WO2010108420A1; CN101848443A

Abstract

Translated fromChinese

本发明实施例公开了一种通信业务切换处理方法、网络系统与互通功能实体，其中方法包括：接收用户终端在源网络发送的第一注册请求消息，完成用户终端到用户终端的服务IWF的注册；接收用户终端在源网络发送的第二注册请求消息，将所述第二注册请求消息发送至用户终端的源服务MME，以使用户终端完成到源服务MME的注册；接收用户终端在源网络的切换请求消息，并将切换请求消息转发给源服务MME，以使源服务MME执行切换流程，将用户终端切换到目标网络。本发明实施例实现了CS域业务从GERAN/UTRAN到E-UTRAN的切换，并避免了CS域业务切换过程中的业务中断。

The embodiment of the present invention discloses a communication service switching processing method, a network system and an interworking functional entity, wherein the method includes: receiving the first registration request message sent by the user terminal on the source network, and completing the registration of the service IWF from the user terminal to the user terminal ; Receive the second registration request message sent by the user terminal on the source network, and send the second registration request message to the source service MME of the user terminal, so that the user terminal completes the registration to the source service MME; The handover request message is forwarded to the source serving MME, so that the source serving MME executes the handover process and handovers the user terminal to the target network. The embodiment of the present invention realizes switching of CS domain services from GERAN/UTRAN to E-UTRAN, and avoids service interruption during the switching process of CS domain services.

Description

Translated fromChinese

通信业务切换处理方法、网络系统与互通功能实体Communication service handover processing method, network system and interworking functional entity

技术领域technical field

本发明涉及通信技术，尤其是一种通信业务切换处理方法、网络系统与互通功能实体。The invention relates to communication technology, in particular to a communication service switching processing method, a network system and an interworking functional entity.

背景技术Background technique

电路交换（Circuit Switched，以下简称：CS）域主要处理语音业务。CS域的信令面控制实体为移动交换中心/拜访位置寄存器（Mobile Switch Center/Visitor Location Register，以下简称：MSC/VLR）。GSM/增强型数据速率GSM演进无线接入网（GSM/EDGE Radio Access Network，以下简称：GERAN）中，无线接入网元基站控制器（Base Station Controller，以下简称：BSC）与基站（Base Transceiver Station，以下简称：BTS）通过A接口与MSC连接。通用移动通信系统（Universal Mobile Telecommunications System，以下简称：UMTS）陆地无线接入网（UMTS Territorial Radio Access Network，以下简称：UTRAN）中，无线接入网元无线网络控制器（Radio Network Controller，以下简称：RNC）与基站（NodeB）通过Iu接口与MSC连接。The circuit switched (Circuit Switched, hereinafter referred to as: CS) domain mainly processes voice services. The signaling plane control entity of the CS domain is the Mobile Switch Center/Visitor Location Register (MSC/VLR for short). In the GSM/Enhanced Data Rate GSM Evolved Radio Access Network (GSM/EDGE Radio Access Network, hereinafter referred to as: GERAN), the wireless access network element base station controller (Base Station Controller, hereinafter referred to as: BSC) and the base station (Base Transceiver Station, hereinafter referred to as: BTS) is connected to MSC through A interface. In the Universal Mobile Telecommunications System (hereinafter referred to as: UMTS) Territorial Radio Access Network (hereinafter referred to as: UTRAN), the wireless access network element radio network controller (Radio Network Controller, hereinafter referred to as : RNC) and the base station (NodeB) are connected to the MSC through the Iu interface.

为了应对无线宽带技术的挑战，保持3GPP网络的领先优势，3GPP在2004年底制定了长期演进（Long Term Evolution，以下简称：LTE）计划。该LTE计划中定义了演进的分组网络（evolved packet system，以下简称：EPS）。EPS核心网主要包含移动管理实体（Mobility Management Entity，以下简称：MME）、服务网关（Serving Gateway，以下简称：S-GW）、分组数据网络网关（Packet Data Network Gateway，以下简称：P-GW）三个逻辑功能体。其中，MME主要用于实现接入层（Access Stratum，以下简称：AS）信令和非接入层（Non Access Stratum，以下简称：NAS）信令加密以及漫游、跟踪，以及分配用户临时身份标识、安全功能等。S-GW主要用于实现本地的移动性锚点和3GPP系统内部的移动性锚点，以及合法监听相关信息功能。P-GW主要用于实现策略执行和计费，以及合法监听相关信息功能。In order to meet the challenge of wireless broadband technology and maintain the leading edge of 3GPP network, 3GPP formulated the Long Term Evolution (LTE) plan at the end of 2004. An evolved packet network (evolved packet system, hereinafter referred to as EPS) is defined in the LTE plan. The EPS core network mainly includes Mobility Management Entity (MME for short), Serving Gateway (S-GW for short), and Packet Data Network Gateway (P-GW for short). Three logical function bodies. Among them, MME is mainly used to implement access layer (Access Stratum, hereinafter referred to as: AS) signaling and non-access layer (Non Access Stratum, hereinafter referred to as: NAS) signaling encryption, roaming, tracking, and allocation of temporary user identities , security features, etc. The S-GW is mainly used to realize the local mobility anchor point and the mobility anchor point within the 3GPP system, as well as the function of legally intercepting related information. The P-GW is mainly used to implement policy enforcement and charging, as well as the functions of legally intercepting relevant information.

随着通信技术的发展与通信业务需求的不断提高，通信业务经常需要在GERAN或UTRAN（以下简称：GERAN/UTRAN）与为LTE系统中接入网的演进的通用移动电信系统陆地无线接入网（Evolved UMTS Terrestrial RadioAccess Network，以下简称：E-UTRAN）之间进行切换。但是，在实现本发明的过程中，发明人发现：由于现有E-UTRAN中的无线接入网元演进基站（Evolved NodeB，以下简称：eNB）无法处理CS域的信令流程，因此，目前仍无法实现GERAN/UTRAN到E-UTRAN的CS域业务切换。With the development of communication technology and the continuous improvement of communication service requirements, communication services often need to be deployed between GERAN or UTRAN (hereinafter referred to as: GERAN/UTRAN) and the evolved universal mobile telecommunications system terrestrial radio access network which is the access network in the LTE system. (Evolved UMTS Terrestrial RadioAccess Network, hereinafter referred to as: E-UTRAN) to switch between. However, in the process of implementing the present invention, the inventors found that: since the Evolved NodeB (hereinafter referred to as eNB) in the existing E-UTRAN cannot handle the signaling process of the CS domain, the current CS domain service handover from GERAN/UTRAN to E-UTRAN still cannot be realized.

发明内容Contents of the invention

本发明实施例的目的是：提供一种通信业务切换处理方法、网络系统与互通功能实体，实现CS域业务从GERAN/UTRAN到E-UTRAN的切换。The purpose of the embodiments of the present invention is to provide a communication service switching processing method, a network system and an interworking functional entity, so as to realize switching of CS domain services from GERAN/UTRAN to E-UTRAN.

本发明实施例提供的一种通信业务切换处理方法，包括：A communication service switching processing method provided by an embodiment of the present invention includes:

接收用户终端在源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务互通功能实体IWF的注册；receiving the first registration request message sent by the user terminal in the source network, and completing the registration of the user terminal to the service interworking function entity IWF of the user terminal;

接收所述用户终端在所述源网络发送的第二注册请求消息，将所述第二注册请求消息发送至用户终端的源服务移动性管理实体MME，以使所述用户终端完成到所述源服务MME的注册；receiving the second registration request message sent by the user terminal on the source network, and sending the second registration request message to the source serving mobility management entity MME of the user terminal, so that the user terminal completes the registration to the source network Registration of the service MME;

接收所述用户终端在所述源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME，以使所述源服务MME执行切换流程，将所述用户终端切换到目标网络。receiving a handover request message of the user terminal on the source network, and forwarding the handover request message to the source serving MME, so that the source serving MME executes a handover process and handovers the user terminal to a target network .

本发明实施例提供的一种互通功能实体，包括：An interworking functional entity provided by an embodiment of the present invention includes:

注册接收单元，用于接收用户终端在源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务IWF的注册；The registration receiving unit is configured to receive the first registration request message sent by the user terminal in the source network, and complete the registration of the user terminal to the service IWF of the user terminal;

转发单元，用于接收所述用户终端在所述源网络发送的第二注册请求消息，并将所述第二注册请求消息转发到所述用户终端的源服务MME，以使所述用户终端完成到所述源服务MME的注册；a forwarding unit, configured to receive the second registration request message sent by the user terminal on the source network, and forward the second registration request message to the source serving MME of the user terminal, so that the user terminal completes registration to said source serving MME;

切换触发单元，用于接收用户终端在所述源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME，以使所述源服务MME执行切换流程，将所述用户终端切换到目标网络。A handover triggering unit, configured to receive a handover request message of the user terminal on 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 transfers the user terminal Switch to the target network.

本发明实施例提供的一种移动交换中心，包括：A mobile switching center provided by an embodiment of the present invention includes:

接收单元，用于接收源网络的接入网元发送的用户终端的切换请求消息；The receiving unit is configured to receive the handover request message of the user terminal sent by the access network element of the source network;

确定单元，用于根据所述接收单元接收到的切换请求消息确定所述终端的服务互通功能实体IWF；A determining unit, configured to determine a service interworking function entity IWF of the terminal according to the handover request message received by the receiving unit;

发送单元，用于将所述切换请求消息发送给所述确定单元确定的服务IWF。a sending unit, configured to send the handover request message to the serving IWF determined by the determining unit.

本发明实施例提供的一种移动性管理实体，包括：A mobility management entity provided by an embodiment of the present invention includes:

接收单元，用于接收用户终端的IWF发送的用户终端的切换请求消息；a receiving unit, configured to receive a handover request message of the user terminal sent by the IWF of the user terminal;

切换单元，用于将用户终端从源网络切换到目标网络。A switching unit, configured to switch the user terminal from the source network to the target network.

本发明实施例提供的一种网络系统，包括MSC、用户终端的服务IWF和用户终端的源服务MME，其中A network system provided by an embodiment of the present invention includes an MSC, a serving IWF of a user terminal, and a source serving MME of a user terminal, wherein

所述MSC，用于接收源网络的接入网元发送的用户终端的切换请求消息，根据所述切换请求消息确定所述用户终端的服务IWF，并将所述切换请求消息发送给所述确定的服务IWF；The MSC is configured to receive the handover request message of the user terminal sent by the access network element of the source network, determine the serving IWF of the user terminal according to the handover request message, and send the handover request message to the determined Services of IWF;

所述服务IWF，用于接收用户终端在所述源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务IWF的注册；接收所述用户终端在所述源网络发送的第二注册请求消息，并将所述第二注册请求消息转发到所述用户终端的源服务MME，以使所述用户终端完成到所述源服务MME的注册；接收所述用户终端在所述源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME，以使所述源服务MME执行切换流程，将所述用户终端切换到目标网络；The serving IWF is configured to receive the first registration request message sent by the user terminal on the source network, and complete the registration of the user terminal to the serving IWF of the user terminal; receive the first registration request message sent by the user terminal on the source network the second registration request message, and forward the second registration request message to the source serving MME of the user terminal, so that the user terminal completes the registration with the source serving MME; receiving the user terminal at the The handover request message of the source network, and forward the handover request message to the source serving MME, so that the source serving MME performs a handover process, and handover the user terminal to the target network;

所述源服务MME，用于接收所述服务IWF发送的用户终端的切换请求消息，将所述用户终端切换从所述源网络切换到所述目标网络。The source serving MME is configured to receive the handover request message of the user terminal sent by the serving IWF, and handover the user terminal from the source network to the target network.

基于本发明上述实施例提供的通信业务切换处理方法、网络系统与互通功能实体，UE可以通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到服务MME，这样，后续UE的CS域业务需要从GERAN/UTRAN切换到E-UTRAN时，服务IWF可以作为E-UTRAN中的目标接入网网元，根据UE注册到服务MME的过程中存储的源服务MME信息，指示服务MME执行CS域业务向E-UTRAN的切换流程，解决了E-UTRAN中的目标接入网网元eNB无法处理CS域信令流程问题，保障了GERAN/UTRAN到E-UTRAN的CS域业务切换的正常进行，从而保证了用户的通信业务质量。Based on the communication service switching processing method, network system and interworking functional entity provided by the above embodiments of the present invention, the UE can register with the IWF through GERAN/UTRAN, and register with the serving MME through the serving IWF. In this way, the subsequent CS domain services of the UE need When switching from GERAN/UTRAN to E-UTRAN, the serving IWF can serve as the target access network element in E-UTRAN, and instruct the serving MME to perform CS domain services according to the source serving MME information stored during the UE registration process with the serving MME The handover process to E-UTRAN solves the problem that the target access network element eNB in E-UTRAN cannot handle the CS domain signaling process, and ensures the normal progress of CS domain service handover from GERAN/UTRAN to E-UTRAN, thereby The communication service quality of the user is guaranteed.

下面通过附图和实施例，对本发明的技术方案做进一步的详细描述。The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

附图说明Description of drawings

图1为GERAN、UTRAN、E-UTRAN与EPS核心网的一个组网结构示意图；Figure 1 is a schematic diagram of a network structure of GERAN, UTRAN, E-UTRAN and EPS core network;

图2a为本发明通信业务切换处理方法一个实施例的流程图；Fig. 2a is a flow chart of an embodiment of the communication service switching processing method of the present invention;

图2b为本发明通信业务切换处理方法另一个实施例的流程图；Fig. 2b is a flow chart of another embodiment of the communication service switching processing method of the present invention;

图3为本发明UE注册到服务IWF以及通过该服务IWF注册到源服务MME一个实施例的流程图；FIG. 3 is a flow chart of an embodiment of the UE registering with the serving IWF and registering with the source serving MME through the serving IWF in the present invention;

图4为本发明UE注册到服务IWF以及通过该服务IWF注册到源服务MME另一个实施例的流程图；FIG. 4 is a flow chart of another embodiment of the UE registering with the serving IWF and registering with the source serving MME through the serving IWF in the present invention;

图5为本发明MSC寻址UE的服务IWF，并发送切换请求消息一个实施例的流程图；FIG. 5 is a flow chart of an embodiment of the MSC addressing the serving IWF of the UE and sending a handover request message in the present invention;

图6为本发明MSC寻址UE的服务IWF，并发送切换请求消息另一个实施例的流程图；FIG. 6 is a flow chart of another embodiment of the MSC addressing the serving IWF of the UE and sending a handover request message according to the present invention;

图7为本发明MSC寻址UE的服务IWF，并发送切换请求消息又一个实施例的流程图；FIG. 7 is a flow chart of another embodiment of the MSC addressing the serving IWF of the UE and sending a handover request message according to the present invention;

图8为本发明通信业务切换处理方法另一个实施例的流程图；FIG. 8 is a flow chart of another embodiment of the communication service switching processing method of the present invention;

图9为本发明服务IWF向源服务MME发送切换请求消息一个实施例的流程图。Fig. 9 is a flowchart of an embodiment of sending a handover request message from the serving IWF to the source serving MME according to the present invention.

图10为本发明IWF一个实施例的结构示意图；Fig. 10 is a schematic structural diagram of an embodiment of the IWF of the present invention;

图11为本发明MSC一个实施例的结构示意图；Figure 11 is a schematic structural diagram of an embodiment of the MSC of the present invention;

图12为本发明MME一个实施例的结构示意图；FIG. 12 is a schematic structural diagram of an embodiment of the MME of the present invention;

图13为本发明网络系统一个实施例的结构示意图。Fig. 13 is a schematic structural diagram of an embodiment of the network system of the present invention.

具体实施方式Detailed ways

由于运营商提供的很多通信业务都运行在CS域中，为了在LTE网络中提供现有的CS业务，现有技术将EPS核心网连接到CS域核心网。如图1所示，为GERAN、UTRAN、演进的通用移动电信系统陆地无线接入网（Evolved UMTS Terrestrial Radio Access Network，以下简称：E-UTRAN）与EPS核心网的一个组网结构示意图。根据图1，用户终端（User Equipment，以下简称：UE）通过互通功能实体（Interworking Function，以下简称：IWF）与CS核心网的MSC相连接。IWF具备模拟Iu-CS/A接口的能力，可以在IWF上配置Iu-CS/A接口对应的协议栈。UE与MSC通信时，首先向IWF发送消息。IWF接收到UE发送的消息后，将其转换成Iu-CS/A接口上的信令格式，并发送给MSC，从而完成UE与MSC的通信。同理，IWF可以将MSC通过Iu-CS/A接口发送的消息转发给UE。Sv为MME与IWF之间的参考点，当LTE网络向GERAN/UTRAN切换时，MME通过Sv向IWF发生切换请求消息。Z1为UE与IWF之间的参考点，可以作为IWF与UE之间的IP通道。Since many communication services provided by operators run in the CS domain, in order to provide existing CS services in the LTE network, the prior art connects the EPS core network to the CS domain core network. As shown in Figure 1, it is a schematic diagram of a network structure of GERAN, UTRAN, Evolved UMTS Terrestrial Radio Access Network (Evolved UMTS Terrestrial Radio Access Network, hereinafter referred to as: E-UTRAN) and EPS core network. According to Figure 1, a user terminal (User Equipment, hereinafter referred to as UE) is connected to an MSC of a CS core network through an interworking function entity (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 the signaling format on the Iu-CS/A interface and sends it to the MSC, thus completing the 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 the reference point between MME and IWF. When the LTE network switches to GERAN/UTRAN, MME sends a switching request message to IWF through Sv. Z1 is a reference point between UE and IWF, and can be used as an IP channel between IWF and UE.

图2a为本发明通信业务切换处理方法一个实施例的流程图，其包括：Fig. 2a is a flowchart of an embodiment of the communication service switching processing method of the present invention, which includes:

S1、接收用户终端在源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务互通功能实体IWF的注册；S1. Receive the first registration request message sent by the user terminal in the source network, and complete the registration from the user terminal to the service interworking function entity IWF of the user terminal;

S2、接收所述用户终端在源网络发送的第二注册请求消息，将所述第二注册请求消息发送至所述用户终端的源服务移动性管理实体MME，以使所述用户终端完成到所述源服务MME的注册；S2. Receive the second registration request message sent by the user terminal on the source network, and send the second registration request message to the source serving mobility management entity MME of the user terminal, so that the user terminal completes the registration to the source network Registration of source service MME;

S3、接收用户终端的在源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME，以使所述源服务MME执行切换流程，将所述用户终端切换到目标网络。S3. Receive a handover request message of the user terminal on the source network, and forward the handover request message to the source serving MME, so that the source serving MME executes a handover procedure to handover the user terminal to the target network.

其中，所述源网络可以是GERAN、UTRAN等网络，所述目标网络可以是E-UTRAN等。本发明实施例所提供的方法，UE可以通过GERAN/UTRAN注册到服务IWF，并通过服务IWF注册到源服务MME，当所述UE的CS域业务从GERAN/UTRAN网络切换到E-UTRAN时，所述MSC通过服务IWF将所述UE的切换请求消息转发给所述源服务MME，指示所述源服务IWF完成所述CS域的切换业务。S2中，将所述第二注册请求消息发送至用户终端的源服务移动性管理实体MME之前，还可以包括：确定所述用户终端的源服务MME。Wherein, the source network may be GERAN, UTRAN and other networks, and the target network may be E-UTRAN and the like. According to the method provided by the embodiment of the present invention, the UE can register with the serving IWF through GERAN/UTRAN, and register with the source serving MME 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 through the serving IWF, and instructs the source serving IWF to complete the CS domain handover service. In S2, before sending the second registration request message to the source serving mobility management entity MME of the user terminal, it may further include: determining the source serving MME of the user terminal.

图2b为本发明通信业务切换处理方法另一个实施例的流程图。如图2b所示，该实施例的通信业务切换处理方法包括以下步骤：Fig. 2b is a flow chart of another embodiment of the communication service switching processing method of the present invention. As shown in Figure 2b, the communication service switching processing method of this embodiment includes the following steps:

步骤101，UE通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到UE的MME。其中的IWF即为UE的服务IWF，MME即为UE的源服务MME。Step 101, the UE registers with the IWF through GERAN/UTRAN, and registers with the UE's MME through the serving IWF. The IWF is the serving IWF of the UE, and the MME is the source serving MME of the UE.

步骤102，GERAN/UTRAN的接入网网元向MSC转发UE的切换请求消息，该切换请求消息中包括CS域切换信息与E-UTRAN中目标接入网网元标识（identifier，以下简称：ID）信息。Step 102, the GERAN/UTRAN access network element forwards the UE's handover request message to the MSC, the handover request message includes CS domain handover information and the target access network element identifier (identifier, hereinafter referred to as: ID in E-UTRAN) )information.

具体地，GERAN/UTRAN的接入网网元具体可以是BSC或者RNC。E-UTRAN中目标接入网网元具体可以是eNB。Specifically, the access network element of the GERAN/UTRAN may specifically be a BSC or an RNC. Specifically, the network element of the target access network in the E-UTRAN may be an eNB.

步骤103，MSC寻址UE的服务IWF，并向服务IWF转发切换请求消息。Step 103, the MSC addresses the serving IWF of the UE, and forwards the handover request message to the serving IWF.

步骤104，服务IWF根据在通过服务IWF注册到源服务MME的过程中存储的源服务MME信息，指示源服务MME执行CS域业务向E-UTRAN的切换流程。Instep 104, the serving IWF instructs the source serving MME to perform a handover process from the CS domain service to the E-UTRAN according to the source serving MME information stored in the process of registering with the source serving MME through the serving IWF.

步骤105，服务IWF在UE接入E-UTRAN后，向MSC发送切换完成通知消息，以便MSC将业务流传递到服务IWF，以及触发E-UTRAN中的承载建立流程，以便业务流通过服务IWF传递到UE。Step 105: After the UE accesses the E-UTRAN, the serving IWF sends a handover completion notification message to the MSC, so that the MSC transfers the service flow to the serving IWF, and triggers the bearer establishment process in the E-UTRAN, so that the service flow is transferred through the serving IWF to UE.

UE可以通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到服务MME，这样，后续UE的CS域业务需要从GERAN/UTRAN切换到E-UTRAN时，服务IWF可以作为E-UTRAN中的目标接入网网元，根据UE注册到服务MME的过程中存储的源服务MME信息，指示服务MME执行CS域业务向E-UTRAN的切换流程，解决了E-UTRAN中的目标接入网网元eNB无法处理CS域信令流程问题，保障了GERAN/UTRAN到E-UTRAN的CS域业务切换的正常进行，从而保证了用户的通信业务质量。The UE can register with the IWF through GERAN/UTRAN, and register with the serving MME through the serving IWF. In this way, when the CS domain service of the UE needs to be switched from GERAN/UTRAN to E-UTRAN, the serving IWF can be used as the target in E-UTRAN The access network element, according to the source serving MME information stored in the process of UE registration with the serving MME, instructs the serving MME to execute the handover process of the CS domain service to E-UTRAN, which solves the problem of the target access network element in E-UTRAN The eNB cannot handle the CS domain signaling process problem, which ensures the normal progress of the CS domain service handover from GERAN/UTRAN to E-UTRAN, thereby ensuring the communication service quality of users.

本发明实施例的通信业务切换处理方法可以适用于任何通信业务，尤其是语音业务。在本发明的以下一些实施例中，以语音业务为例进行说明，对于其它业务同样适用。The communication service switching processing method in the embodiment of the present invention can be applied to any communication service, especially voice service. In some of the following embodiments of the present invention, the voice service is taken as an example for description, which is also applicable to other services.

在图2所示实施例的步骤101中，UE具体可以采取以下两种方式，通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到该UE的MME：Instep 101 of the embodiment shown in FIG. 2 , the UE can specifically adopt the following two methods to register with the IWF through GERAN/UTRAN, and register with the MME of the UE through the serving IWF:

一种是UE通过GERAN/UTRAN的CS域注册到UE的服务IWF，并通过服务IWF注册到UE的源服务MME。具体地，UE完成CS域附着后，可以由CS域业务触发UE通过GERAN/UTRAN的CS域注册到UE的服务IWF，这相当于UE主动触发注册到UE的服务IWF。另外，在UE要进行网络切换时，GERAN/UTRAN的接入网网元也可以通知UE向IWF注册。这相当于UE被动触发注册到UE的服务IWF。One is that the UE registers with the serving IWF of the UE through the CS domain of GERAN/UTRAN, and registers with the source serving MME of the UE through the serving IWF. Specifically, after the UE attaches to the CS domain, the CS domain service can trigger the UE to register with the serving IWF of the UE through the CS domain of GERAN/UTRAN, which is equivalent to the UE actively triggering registration to the serving IWF of the UE. In addition, when the UE is going to perform network handover, the GERAN/UTRAN access network element may also notify the UE to register with the IWF. This is equivalent to the UE passively triggering registration to the serving IWF of the UE.

另一种是UE通过GERAN/UTRAN的分组交换PS域注册到UE的服务IWF，并通过服务IWF注册到UE的源服务MME。具体地，UE完成PS域附着后，可以由CS域业务触发UE通过GERAN/UTRAN的PS域注册到UE的服务IWF，这相当于UE主动触发注册到UE的服务IWF。另外，在UE要进行网络切换时，GERAN/UTRAN的接入网网元也可以通知UE向IWF注册。这相当于UE被动触发注册到UE的服务IWF。The other is that the UE registers with the serving IWF of the UE through the packet switched PS domain of GERAN/UTRAN, and registers with the source serving MME of the UE through the serving IWF. Specifically, after the UE attaches to the PS domain, the CS domain service may trigger the UE to register with the UE's serving IWF through the GERAN/UTRAN PS domain, which is equivalent to the UE actively triggering registration to the UE's serving IWF. In addition, when the UE is going to perform network handover, the GERAN/UTRAN access network element may also notify the UE to register with the IWF. This is equivalent to the UE passively triggering registration to the serving IWF of the UE.

图3为本发明UE注册到服务IWF以及通过该服务IWF注册到源服务MME一个实施例的流程图。该实施例中，UE通过GERAN/UTRAN的CS域注册到UE的服务IWF，并通过服务IWF注册到UE的源服务MME。UE注册到其服务IWF之前，先建立UE与其服务IWF之间的通道，以便UE与IWF之间通过该通道进行信令交互或者数据交互。根据本发明的一个实施例，UE可以与其服务IWF之间可以通过非结构化补充数据业务（UnstructuredSupplementary Service Data，以下简称：USSD）方式建立USSD隧道，作为UE与其服务IWF之间的通道。在USSD方式中，IWF可以看作USSD服务器。如图3所示，该实施例的流程具体包括以下步骤：Fig. 3 is a flow chart of an embodiment of the UE registering with the serving IWF and registering with the source serving MME through the serving IWF according to the present invention. In this embodiment, the UE registers with the UE's serving IWF through the GERAN/UTRAN CS domain, and registers with the UE's source serving MME through the serving IWF. Before the UE registers with its serving IWF, a channel between the UE and its serving IWF is established first, so that the UE and the IWF can perform signaling interaction or data interaction through the channel. According to an embodiment of the present invention, a USSD tunnel can be established between the UE and its serving IWF through an unstructured supplementary data service (Unstructured Supplementary Service Data, hereinafter referred to as: USSD) as a channel between the UE and its serving IWF. In the USSD mode, the IWF can be regarded as a USSD server. As shown in Figure 3, the process of this embodiment specifically includes the following steps:

步骤201，服务IWF接收UE通过USSD隧道发送的第一注册请求消息，例如：UE-IWF-RC REGISTER REQUEST。该第一注册请求消息由UE依次经过GERAN/UTRAN的接入网网元BSC/RNC和MSC发送给服务IWF，用于请求注册到服务IWF，第一注册请求消息中包括用户标识与UE在GERAN/UTRAN中的当前位置信息。其中的用户标识具体可以是国际移动用户识别码（International Mobile Subscriber Identification Number，以下简称：IMSI），UE在GERAN/UTRAN中的当前位置信息具体可以是UE在GERAN/UTRAN中的当前位置区域标识（Location Area Identity，以下简称：LAI）、路由区标识（Routing Area Identity，以下简称：RAI）或小区全球标识（Cell Global Identifier，以下简称：CGI）。Step 201, the serving IWF receives the 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 sequentially through the access network elements BSC/RNC and MSC of GERAN/UTRAN to request registration to the serving IWF. / Current location information in UTRAN. The user identifier may specifically be an International Mobile Subscriber Identification Number (International Mobile Subscriber Identification Number, hereinafter referred to as: IMSI), and the current location information of the UE in GERAN/UTRAN may specifically be the current location area identifier of the UE in GERAN/UTRAN ( Location Area Identity (hereinafter referred to as: LAI), Routing Area Identity (hereinafter referred to as: RAI) or Cell Global Identifier (hereinafter referred to as: CGI).

步骤202，服务IWF处理第一注册请求消息。Step 202, the serving IWF processes the first registration request message.

步骤203，服务IWF依次经过MSC和GERAN/UTRAN的接入网网元BSC/RNC向UE返回第一注册接受消息，例如：UE-IWF-RC REGISTERACCEPT。In step 203, the serving IWF returns the first registration acceptance message to UE via MSC and GERAN/UTRAN access network element BSC/RNC in turn, for example: UE-IWF-RC REGISTERACCEPT.

步骤204，服务IWF接收UE通过USSD隧道发送的第二注册请求消息，该第二注册请求消息由UE依次经过GERAN/UTRAN的接入网网元BSC/RNC和MSC发送给服务IWF，用于请求注册到源服务MME，具体可以是附着请求消息Attach Request，也可以是跟踪区更新请求消息TAURequest，可以包含在UE与服务IWF交互的消息UE-IWF UL DIRECTTRANSFER中。Step 204, the serving IWF receives the second registration request message sent by the UE through the USSD tunnel, and the second registration request message is sent by the UE to the serving IWF through the access network elements BSC/RNC and MSC of GERAN/UTRAN in order to request To register with the source serving MME, it may specifically be an Attach Request message, or a Tracking Area Update Request message TAURequest, which may be included in the UE-IWF UL DIRECTTRANSFER message interacted between the UE and the serving IWF.

步骤205，服务IWF为UE选择源服务MME，并向选择的源服务MME转发第二注册请求消息。具体地，若第二注册请求消息包含在UE与服务IWF交互的消息UE-IWF UL DIRECT TRANSFER中，则服务IWF接收到消息UE-IWF UL DIRECT TRANSFER后，先进行解析，获得UE发送的第二注册请求消息。Step 205, the serving IWF selects a source serving MME for the UE, and forwards the second registration request message to the selected source serving MME. Specifically, if the second registration request message is included in the UE-IWF UL DIRECT TRANSFER message exchanged between the UE and the serving IWF, the serving IWF first analyzes the message after receiving the UE-IWF UL DIRECT TRANSFER message to obtain the second registration request message sent by the UE. Register request message.

具体地，服务IWF可以通过以下方式为UE选择源服务MME包括：Specifically, the serving IWF can select the source serving MME for the UE in the following ways:

服务IWF检测接收到的第二注册请求消息中是否包括MME信息。The serving IWF detects whether the received second registration request message includes MME information.

若第二注册请求消息中未包括MME信息，服务IWF根据预先设定，从MME列表中选择满足预设条件的MME作为源服务MME，该MME列表可保存在服务IWF上。其中根据预先设定可以包括预先设定服务IWF在接收到第二注册请求消息后，在MME列表内任意选择一个MME作为源服务MME；或者预先设定服务IWF在接收到第二注册请求消息后，在MME列表内选择一个负载小的MME作为源服务MME；也可以根据预先设定的其它策略规则选择所述用户终端的源服务MME。If the second registration request message does not include MME information, the serving IWF selects an MME that satisfies the preset condition from the MME list as the source serving MME according to preset settings, and the MME list can be saved on the serving IWF. According to the presetting, it may include presetting that after receiving the second registration request message, the presetting service IWF randomly selects an MME in the MME list as the source serving MME; or presetting the service IWF after receiving the second registration request message , select an MME with a small load in the MME list as the source serving MME; or select the source serving MME of the user terminal according to other preset policy rules.

若第二注册请求消息中包括MME信息，服务IWF查询第二注册请求消息中包括的MME信息标识的MME是否存在于预先存储的MME列表中。若存在于MME列表中，服务IWF选择第二注册请求消息中包括的MME信息标识的MME作为源服务MME。若不存在于MME列表中，服务IWF根据预先设定，从MME列表中选择满足预设条件的MME作为源服务MME。当第二注册请求消息中所包含的MME信息不在所述MME列表上时，服务IWF选择源服务MME的过程可以参照第二注册请求消息中不包含MME信息时的处理。If the MME information is included in the second registration request message, the serving 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 satisfying the preset condition from the MME list as the source serving MME according to preset settings. When the MME information included in the second registration request message is not in the MME list, the process of selecting the source serving MME by the serving IWF may refer to the processing when the second registration request message does not include MME information.

具体的，MME信息可以是全球唯一临时标识（Globally UniqueTemporary Identity，以下简称GUTI）或者MME ID。Specifically, the MME information may be a Globally Unique Temporary Identity (Globally Unique Temporary Identity, GUTI for short) or an MME ID.

步骤206，源服务MME处理第二注册请求消息，并向所述服务IWF返回第二注册接受消息，该第二注册接受消息具体可以是附着接受消息Attach Accept，也可以是跟踪区更新接受消息TAU Accept。Step 206, the source serving MME processes the second registration request message, and returns a second registration acceptance message to the serving IWF. The second registration acceptance message may specifically be an Attach Accept message, or a Tracking Area Update Accept message TAU Accept.

步骤207，服务IWF依次经过MSC和GERAN/UTRAN的接入网网元BSC/RNC向UE返回第二注册接受消息，并将源服务MME信息保存在UE的上下文中，以便在后续流程中，服务IWF寻址为该UE服务的源服务MME。具体地，第二注册接受消息Attach Accept/TAU Accept可以包含在UE与服务IWF交互的消息UE-IWF DL DIRECT TRANSFER中。Step 207, the serving IWF returns the second registration acceptance message to the UE through the MSC and the access network element BSC/RNC of GERAN/UTRAN in turn, and saves the source serving MME information in the context of the UE, so that in the subsequent process, the service The IWF addresses the source serving MME serving the UE. Specifically, the second registration acceptance message Attach Accept/TAU Accept may be included in the UE-IWF DL DIRECT TRANSFER message exchanged between the UE and the serving IWF.

至此，UE完成通过GERAN/UTRAN到IWF的注册，进而通过服务IWF完成到MME的注册。So far, the UE completes the registration with the IWF through GERAN/UTRAN, and then completes the registration with the MME through the serving IWF.

另外，在步骤201中，服务IWF还可以根据UE发送的第一注册请求消息，获取UE当前的小区信息，也即：UE在GERAN/UTRAN中的当前位置信息。相应的，步骤204中，服务IWF接收到UE发送的第二注册请求消息后，还可以执行以下操作：服务IWF根据预先设置的转换关系，将UE当前位置信息转换为E-UTRAN的位置信息，并将该E-UTRAN的位置信息发送给源服务MME。或者，服务IWF以预先配置的E-UTRAN的位置信息，作为UE在E-UTRAN的位置信息，发送给源服务MME，以便后续移动性关联或者会话关联流程使用。In addition, in step 201, the serving IWF may also 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 GERAN/UTRAN. Correspondingly, in step 204, after receiving the second registration request message sent by the UE, the serving IWF may also perform the following operations: the serving IWF converts the current location information of the UE into the location information of the E-UTRAN according to the preset conversion relationship, And send the location information of the E-UTRAN to the source serving MME. Alternatively, the serving IWF sends the pre-configured E-UTRAN location information as the UE location information in the E-UTRAN to the source serving MME for use in subsequent mobility association or session association procedures.

由于E-UTRAN网络中，UE与其服务IWF之间的通道是基于IP的，对于IWF来说，需要记录UE的IP地址，而通过上述图3所示的实施例，UE与其服务IWF之间的通道是USSD隧道，是非IP的。因此，UE完成到源服务MME的注册后，还需要重新建立UE到其服务IWF的IP通道，向IWF提供其IP地址信息，即：UE在EPS网络中重新向其服务IWF注册，通过注册流程向其服务IWF提供IP地址信息。如果之前在GERAN/UTRAN中已经执行了UE到其服务IWF的注册，在执行通过EPS网络完成到服务IWF注册的流程之前，UE需要执行在GERAN/UTRAN到服务IWF的去注册，然后发起通过EPS网络完成到服务IWF注册的流程。此时，其服务IWF就是之前GERAN/UTRAN中的服务IWF。也就是说，在图3所示流程的步骤207之后，还包括：源服务MME建立UE到IWF的互联网协议IP通道；服务IWF接收UE发送的UE的IP地址信息。Since in the E-UTRAN network, the channel between the UE and its serving IWF is based on IP, for the IWF, it is necessary to record the IP address of the UE, and through the embodiment shown in Figure 3 above, the channel between the UE and its serving IWF The channel is a USSD tunnel, which is non-IP. Therefore, after the UE completes the registration with the source serving MME, it needs to re-establish the IP channel from the UE to its serving IWF, and provide its IP address information to the IWF, that is, the UE re-registers with its serving IWF in the EPS network, and through the registration process Provide IP address information to its serving IWF. If the registration of the UE to its serving IWF has been performed in GERAN/UTRAN before, before performing the process of completing the registration to the serving IWF through the EPS network, the UE needs to perform the de-registration to the serving IWF in GERAN/UTRAN, and then initiate the registration through the EPS The network completes the process of registering with the serving IWF. At this time, its serving IWF is the serving IWF in the previous GERAN/UTRAN. That is to say, after step 207 of the process shown in FIG. 3 , it also includes: the source serving MME establishes an Internet Protocol IP channel from the UE to the IWF; and the serving IWF receives the UE's IP address information sent by the UE.

其中，源服务MME建立UE到IWF的互联网协议IP通道包括：Among them, the source serving MME establishes the Internet protocol IP channel from UE to IWF including:

源服务MME接收UE发送的分组数据网络（Packet Data Network，以下简称：PDN）连接请求消息PDN Connectivity Request。该PDN连接请求消息中使用的接入点名称（APN Access Point Name，以下简称：APN）信息，可以是缺省的APN，也可以是其它APN。UE可以在附着网络的过程中发起该PDN连接请求，也可以在附着网络以后发起该PDN连接请求；The source serving MME receives a packet data network (Packet Data Network, hereinafter referred to as: PDN) connection request message PDN Connectivity Request sent by the UE. The access point name (APN Access Point Name, hereinafter referred to as: APN) information used in the PDN connection request message may be the default APN or other APNs. The UE can initiate the PDN connection request during the process of attaching to the network, or initiate the PDN connection request after attaching to the network;

源服务MME向S-GW/P-GW发送创建缺省承载请求Create DefaultBearer Request；The source serving MME sends a Create Default Bearer Request to the S-GW/P-GW;

S-GW/P-GW与源服务MME之间创建承载，并向源服务MME返回创建缺省承载响应Create Default Bearer Response；Create a bearer between the S-GW/P-GW and the source serving MME, and return Create Default Bearer Response to the source serving MME;

源服务MME向UE返回PDN连接接受消息PDN Connectivity Accept。The source serving MME returns a PDN Connectivity Accept message to the UE.

上述PDN连接的建立流程，实际上是预先将EPS网络中执行CS业务的通道准备好，PDN连接的建立为UE到其服务IWF建立起一个IP通道，通过上述流程建立EPS网络中CS域业务相关的PDN连接后，UE就可以与其服务IWF通过该IP通道实现信令交互或者数据交互，以便UE完成到其服务IWF的注册，另外，UE也可以获得后续进行EPS网络中CS域业务的IP地址。有利于后续的切换流程。The above-mentioned PDN connection establishment process actually prepares the channel for performing CS services in the EPS network in advance. The establishment of the PDN connection establishes an IP channel for the UE to serve IWF. After the PDN connection of the service IWF, the UE can realize signaling interaction or data interaction with the serving IWF through the IP channel, so that the UE can complete the registration with its serving IWF. In addition, the UE can also obtain the IP address for subsequent CS domain services in the EPS network . It is beneficial to the subsequent switching process.

服务IWF接收UE发送的UE的IP地址信息包括：The UE's IP address information received by the serving IWF from the UE includes:

服务IWF接收UE通过IP通道发送的第三注册请求消息，例如：UE-IWF-RC REGISTER REQUEST，该第三注册请求消息中包括UE的IP地址信息；The serving IWF receives the third registration request message sent by the UE through the IP channel, for example: UE-IWF-RC REGISTER REQUEST, the third registration request message includes the IP address information of the UE;

服务IWF存储UE的IP地址信息，并向UE返回第三注册接受消息，例如：UE-IWF-RC REGISTER ACCEPT。The serving IWF stores the IP address information of the UE, and returns a third registration acceptance message to the UE, for example: UE-IWF-RC REGISTER ACCEPT.

至此，EPS网络中UE到其服务IWF之间的IP通道已经预先建立完成。So far, the IP channel between the UE and its serving IWF in the EPS network has been pre-established.

UE通过GERAN/UTRAN的分组交换PS域注册到其服务IWF之前，先建立UE到其服务IWF之间的IP通道，以便UE与IWF之间通过该IP通道进行信令交互或者数据交互。根据本发明的一个实施例，UE可以与其服务IWF之间可以建立GPRS隧道协议（GPRS Tunneling Protocol，以下简称：GTP）隧道，作为UE与其服务IWF之间的IP通道。如图4所示，具体可以通过如下流程在UE与其服务IWF之间建立GTP隧道：Before the UE registers with its serving IWF through the packet-switched PS domain of GERAN/UTRAN, an IP channel between the UE and its serving IWF is first established, so that the UE and the IWF can perform signaling or data interaction through the IP channel. According to an embodiment of the present invention, a GPRS Tunneling Protocol (GPRS Tunneling Protocol, GTP for short) tunnel can be established 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 through the following procedures:

步骤30A，UE通过GERAN/UTRAN的接入网网元BSC/RNC，向通用分组无线业务服务支持节点（Serving GPRS Support Node，以下简称SGSN）发送PDP激活请求消息Activate PDP Context Request，该PDP激活请求消息中携带的APN信息，可以是缺省的APN，也可以是其它APN。Step 30A, the UE sends a PDP activation request message Activate PDP Context Request to the Serving GPRS Support Node (SGSN for short) through the access network element BSC/RNC of GERAN/UTRAN, the PDP activation request The APN information carried in the message may be the default APN or other APNs.

步骤30B，SGSN向S-GW/P-GW发送创建PDP请求消息Create PDPContext Request，请求创建该SGSN与S-GW/P-GW之间的承载。In step 30B, the SGSN sends a create PDP request message Create PDPContext Request to the S-GW/P-GW, requesting to create a bearer between the SGSN and the S-GW/P-GW.

步骤30C，S-GW/P-GW与SGSN之间创建承载，并向SGSN返回创建PDP响应消息Create PDP Context Response。In step 30C, a bearer is created between the S-GW/P-GW and the SGSN, and a Create PDP Context Response message is returned to the SGSN.

步骤30D，SGSN通过GERAN/UTRAN的接入网网元BSC/RNC，向UE回复PDP激活接受消息Activate PDP Context Accept。In step 30D, the SGSN replies the PDP activation acceptance message Activate PDP Context Accept to the UE through the GERAN/UTRAN access network element BSC/RNC.

图4为本发明UE注册到服务IWF以及通过该服务IWF注册到源服务MME另一个实施例的流程图。UE与其服务IWF之间建立GTP隧道以后，UE通过GERAN/UTRAN的PS域注册到UE的服务IWF，并通过服务IWF注册到UE的源服务MME。如图4所示，该实施例的流程具体包括以下步骤：Fig. 4 is a flow chart of another embodiment of the UE registering with the serving IWF and registering with the source serving MME through the serving IWF according to the present invention. After the GTP tunnel is established between the UE and its serving IWF, the UE registers with the serving IWF of the UE through the PS domain of GERAN/UTRAN, and registers with the source serving MME of the UE through the serving IWF. As shown in Figure 4, the process of this embodiment specifically includes the following steps:

步骤301，服务IWF接收UE通过GTP隧道发送的第一注册请求消息，例如：UE-IWF-RC REGISTER REQUEST。该第一注册请求消息由UE依次经过GERAN/UTRAN的接入网网元BSC/RNC和SGSN发送给服务IWF，用于请求注册到服务IWF，第一注册请求消息中包括用户标识与UE在GERAN/UTRAN中的当前位置信息。其中的用户标识具体可以是IMSI，UE在GERAN/UTRAN中的当前位置信息具体可以是UE在GERAN/UTRAN中的当前LAI、RAI或CGI。Step 301, the serving IWF receives the 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 sequentially through the access network elements BSC/RNC and SGSN of GERAN/UTRAN to request registration to the serving IWF. / Current location information in UTRAN. The user identifier may specifically be an IMSI, and the current location information of the UE in the GERAN/UTRAN may specifically be the current LAI, RAI or CGI of the UE in the GERAN/UTRAN.

步骤302，服务IWF处理第一注册请求消息。Step 302, the serving IWF processes the first registration request message.

步骤303，服务IWF依次经过SGSN和GERAN/UTRAN的接入网网元BSC/RNC向UE返回第一注册接受消息，例如：UE-IWF-RC REGISTERACCEPT。In step 303, the serving IWF returns a first registration acceptance message to the UE via the SGSN and the access network element BSC/RNC of GERAN/UTRAN in sequence, for example: UE-IWF-RC REGISTERACCEPT.

步骤304，服务IWF接收UE通过GTP隧道发送的第二注册请求消息，该第二注册请求消息由UE依次经过GERAN/UTRAN的接入网网元BSC/RNC和SGSN发送给服务IWF，用于请求注册到源服务MME，具体可以是附着请求消息Attach Request，也可以是跟踪区更新请求消息TAURequest，可以包含在UE与服务IWF交互的消息UE-IWF UL DIRECTTRANSFER中。Step 304, the serving IWF receives the 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 elements BSC/RNC and SGSN of GERAN/UTRAN in order to request To register with the source serving MME, it may specifically be an Attach Request message, or a Tracking Area Update Request message TAURequest, which may be included in the UE-IWF UL DIRECTTRANSFER message interacted between the UE and the serving IWF.

步骤305，服务IWF为UE选择源服务MME，并向选择的源服务MME转发第二注册请求消息。具体地，若第二注册请求消息包含在UE与服务IWF交互的消息UE-IWF UL DIRECT TRANSFER中，则服务IWF接收到消息UE-IWF UL DIRECT TRANSFER后，先进行解析，获得UE发送的第二注册请求消息。In step 305, the serving IWF selects a source serving MME for the UE, and forwards the second registration request message to the selected source serving MME. Specifically, if the second registration request message is included in the UE-IWF UL DIRECT TRANSFER message exchanged between the UE and the serving IWF, the serving IWF first analyzes the message after receiving the UE-IWF UL DIRECT TRANSFER message to obtain the second registration request message sent by the UE. Register request message.

具体地，服务IWF为UE选择源服务MME的方法可以参考步骤205。Specifically, the method for the serving IWF to select the source serving MME for the UE may refer to step 205 .

步骤306，源服务MME处理第二注册请求消息，并向所述服务IWF返回第二注册接受消息，该第二注册接受消息具体可以是附着接受消息Attach Accept，也可以是跟踪区更新接受消息TAU Accept。Step 306, the source serving MME processes the second registration request message, and returns a second registration acceptance message to the serving IWF. The second registration acceptance message may specifically be an Attach Accept message or a Tracking Area Update Accept message TAU Accept.

步骤307，服务IWF依次经过SGSN和GERAN/UTRAN的接入网网元BSC/RNC向UE返回第二注册接受消息，并将源服务MME信息保存在UE的上下文中，以便在后续流程中，服务IWF寻址为该UE服务的源服务MME。具体地，第二注册接受消息Attach Accept/TAU Accept可以包含在UE与服务IWF交互的消息UE-IWF DL DIRECT TRANSFER中。Step 307, the serving IWF returns the second registration acceptance message to the UE through the SGSN and the access network element BSC/RNC of GERAN/UTRAN in turn, and saves the information of the source serving MME in the context of the UE, so that in the subsequent process, the service The IWF addresses the source serving MME serving the UE. Specifically, the second registration acceptance message Attach Accept/TAU Accept may be included in the UE-IWF DL DIRECT TRANSFER message exchanged between the UE and the serving IWF.

由于GTP隧道已经是IP模式了，通过图4所示实施例的流程，可以不需要在重新建立UE到其服务IWF的IP通道。后续执行GERAN/UTRAN向E-UTRAN切换时，由GERAN/UTRAN网络同步到E-UTRAN网络，也就是说，由GERAN/UTRAN网络向E-UTRAN进行网络切换时，UE的IP地址不变。Since the GTP tunnel is already in IP mode, through the process of the embodiment shown in FIG. 4 , it may not be necessary to re-establish the IP channel from the UE to its serving IWF. When subsequent handover from GERAN/UTRAN to E-UTRAN is performed, the GERAN/UTRAN network is synchronized to the E-UTRAN network, that is, when the network handover is performed from the GERAN/UTRAN network to E-UTRAN, the IP address of the UE remains unchanged.

通过上述图3与图4所示的流程，UE完成在GERAN/UTRAN到服务IWF的注册，进而通过服务IWF完成到源服务MME的注册，就可以通过该源服务MME预先建立UE到服务IWF的通道，从而可以减少后续CS域业务切换的时延，提高通信质量与用户的业务体验。Through the procedures shown in Figure 3 and Figure 4 above, the UE completes the registration with the serving IWF in GERAN/UTRAN, and then completes the registration with the source serving MME through the serving IWF, and then the UE can pre-establish a connection with the serving IWF through the source serving MME. channel, so as to reduce the delay of the subsequent CS domain service handover, improve the communication quality and the service experience of the user.

在UE通过IWF完成到MME注册的过程中，服务IWF实际上执行了eNB的接口功能，即：服务IWF需要配置S1接口的相应协议栈，这样才可以与源服务MME通信。通过步骤202或步骤302，UE完成到服务IWF的注册后，服务IWF可以为UE创建该UE的上下文。因此，在图2所示实施例的步骤104中，服务IWF指示源服务MME执行CS域业务向E-UTRAN的切换流程时，需要首先检测源服务MME与E-UTRAN中的目标接入网网元之间是否建立S1连接。若已建立S1连接，则服务IWF直接指示源服务MME执行CS域业务向E-UTRAN的切换流程。若未建立S1连接，则服务IWF触发源服务MME建立与目标接入网网元之间的S1连接，并在建立S1连接后，指示源服务MME执行CS域业务向E-UTRAN的切换流程。When the UE registers with the MME through the IWF, the serving IWF actually performs the interface function of the eNB, that is, the serving IWF needs to configure the corresponding protocol stack of the S1 interface so that it can communicate with the source serving MME. Through step 202 or step 302, after the UE completes the registration with the serving IWF, the serving IWF can create the context of the UE for the UE. Therefore, instep 104 of the embodiment shown in FIG. 2 , when the serving IWF instructs the source serving MME to execute the handover process of CS domain services to E-UTRAN, it needs to first detect the source serving MME and the target access network in E-UTRAN. Whether to establish an S1 connection between elements. If the S1 connection has been established, the serving IWF directly instructs the source serving MME to perform a handover process from the CS domain service to the E-UTRAN. If the S1 connection is not established, the serving IWF triggers the source serving MME to establish an S1 connection with the network element of the target access network, and instructs the source serving MME to execute the handover process from the CS domain service to the E-UTRAN after the S1 connection is established.

现有技术中，发生CS域切换的时候，源GERAN/UTRAN的接入网网元BSC/RNC只会向源MSC上报目标接入网网元ID信息。因此，对于CS域切换，现有技术的一个处理难点是，如何保证切换的时候MSC能够与UE的服务IWF关联起来，以便于MSC寻址UE的服务IWF，而不是与E-UTRAN中的目标接入网网元eNB关联起来。图5为本发明MSC寻址UE的服务IWF，并发送切换请求消息一个实施例的流程图。如图5所示，该实施例包括以下步骤：In the prior art, when a CS domain handover occurs, the source GERAN/UTRAN access network element BSC/RNC will only report the target access network element ID information to the source MSC. Therefore, for CS domain handover, one of the difficulties in the existing technology is how to ensure that the MSC can be associated with the serving IWF of the UE during the handover, so that the MSC can address the serving IWF of the UE instead of the target in E-UTRAN. The access network elements eNB are associated. FIG. 5 is a flowchart of an embodiment of the present invention in which the MSC addresses the serving IWF of the UE and sends a handover request message. As shown in Figure 5, this embodiment includes the following steps:

步骤401，GERAN/UTRAN的接入网网元BSC/RNC接收UE上报的切换测量报告，该切换测量报告中包括E-UTRAN的测量信息与UE注册的服务IWF的测量信息。In step 401, the access network element BSC/RNC of GERAN/UTRAN receives the handover measurement report reported by the UE, and the handover measurement report includes the measurement information of E-UTRAN and the measurement information of the serving IWF registered by the UE.

本发明实施例中，UE上报测量报告时，可以标识出E-UTRAN的测量信息和IWF的测量信息。根据UE的标识，接入网网元可以识别UE上报的E-UTAN的测量信息和IWF的测量信息。其中，IWF的测量信息来源于UE执行IWF的发现和注册过程中，注册的IWF向UE提供的IWF系统信息。In the embodiment of the present invention, when the UE reports the measurement report, it can identify the measurement information of the E-UTRAN and the measurement information of the IWF. According to the identifier of the UE, the network element of the access network can identify the measurement information of the E-UTAN and the measurement information of the IWF reported by the UE. Wherein, the measurement information of the IWF comes from the IWF system information provided by the registered IWF to the UE during the process of discovering and registering the IWF performed by the UE.

步骤402，GERAN/UTRAN的接入网网元BSC/RNC根据E-UTRAN的测量信息与UE注册的服务IWF的测量信息决策发起切换流程时，向MSC发送切换请求消息，该切换请求消息中包括服务IWF的相关信息，服务IWF的相关信息对应服务IWF的测量信息。Step 402, when the access network element BSC/RNC of GERAN/UTRAN decides to initiate a handover process according to the measurement information of E-UTRAN and the measurement information of the serving IWF registered by the UE, it sends a handover request message to the MSC, and the handover request message includes The relevant information of the serving IWF, the relevant information of the serving IWF corresponds to the measurement information of the serving IWF.

步骤403，MSC根据服务IWF的相关信息寻址UE的服务IWF，并向该服务IWF发送切换请求消息。Step 403, the MSC addresses the serving IWF of the UE according to the relevant information of the serving IWF, and sends a handover request message to the serving IWF.

具体地，步骤401中，服务IWF的测量信息可以为服务IWF的小区信息，例如：频率信道号（Absolute Radio Frequency Channel Number，以下简称：ARFCN）、基站识别码（base station identity code，以下简称：BSIC），步骤403中，服务IWF的相关信息具体为服务IWF的目标标识/目标小区信息。相应的，步骤402之前，还包括：GERAN/UTRAN的接入网网元将服务IWF的小区信息映射为小区全球标识CGI，并根据预先设置的CGI与目标标识/目标小区之间的对应关系信息，获取与CGI对应的目标标识/目标小区信息。步骤403具体为：MSC根据服务IWF的目标标识/目标小区与IWF之间的对应关系信息，寻址UE的服务IWF。Specifically, in step 401, the measurement information of the serving IWF may be cell information of the serving IWF, for example: Absolute Radio Frequency Channel Number (ARFCN for short), base station identity code (base station identity code, short for short below): BSIC), in step 403, the relevant information of the serving IWF is specifically the target identity/target cell information of the serving IWF. Correspondingly, before step 402, it also includes: the GERAN/UTRAN access network element maps the cell information of the serving IWF to the cell global identity CGI, and according to the preset correspondence information between the CGI and the target identity/target cell to acquire the target identity/target cell information corresponding to the CGI. Step 403 is specifically: the MSC addresses the serving IWF of the UE according to the corresponding relationship information between the target identifier/target cell and the IWF of the serving IWF.

服务IWF的测量信息与服务IWF的相关信息也可以具体为服务IWF的地址信息，例如：序列号。相应的，步骤403中，MSC对服务IWF的地址信息进行域名系统（Domain Name System，以下简称：DNS）解析，得到服务IWF的地址，并根据该服务IWF的地址寻址服务IWF。The measurement information of the serving IWF and related information of the serving IWF may also specifically be address information of the serving IWF, for example, a serial number. Correspondingly, in step 403, the MSC performs domain name system (Domain Name System, hereinafter referred to as: DNS) analysis on the address information of the serving IWF to obtain the address of the serving IWF, and addresses the serving IWF according to the address of the serving IWF.

图6为本发明MSC寻址UE的服务IWF，并发送切换请求消息另一个实施例的流程图。该实施例中，UE的服务IWF将自己注册到归属用户服务器（Home Subscriber Server，以下简称：HSS）中，进行网络切换时，MSC发现UE切换的目标网络是E-UTRAN，则向HSS请求IWF地址信息。如图6所示，该实施例包括以下步骤：FIG. 6 is a flow chart of another embodiment of the present invention in which the MSC addresses the serving IWF of the UE and sends a handover request message. In this embodiment, the serving IWF of the UE registers itself in the Home Subscriber Server (HSS for short), and when performing network handover, the MSC finds that the target network of the UE handover is E-UTRAN, and then requests the IWF from the HSS Address information. As shown in Figure 6, this embodiment includes the following steps:

步骤501，服务IWF接收UE发送的第一注册请求消息，例如：UE-IWFREGISTER REQUEST。Step 501, the serving IWF receives the first registration request message sent by the UE, for example: UE-IWFREGISTER REQUEST.

步骤502，服务IWF向UE的HSS发送第四注册请求消息，例如：Update Location Request。第四注册请求消息中包括服务IWF的相关信息，例如：IWF ID，根据该IWF ID，可以寻址相应的IWF。另外，第四注册请求消息还包括UE用户的IMSI。Step 502, the serving IWF sends a fourth registration request message, for example: Update Location Request, to the HSS of the UE. The fourth registration request message includes relevant information of the serving IWF, for example: IWF ID, and the corresponding IWF can be addressed according to the IWF ID. In addition, the fourth registration request message also includes the IMSI of the UE user.

步骤503，HSS对服务IWF进行注册，并向服务IWF返回第四注册响应消息。Step 503, the HSS registers with the serving IWF, and returns a fourth registration response message to the serving IWF.

步骤504，服务IWF向UE返回第四注册响应消息，例如：GA-RCREGISTER ACCEPT，注册响应消息中包含IWF系统信息。Step 504, the serving IWF returns a fourth registration response message to the UE, for example: GA-RCREGISTER ACCEPT, and the registration response message includes IWF system information.

步骤505，UE向GERAN/UTRAN的接入网网元BSC/RNC上报切换测量报告。In step 505, the UE reports a handover measurement report to the access network element BSC/RNC of the GERAN/UTRAN.

步骤506，GERAN/UTRAN的接入网网元BSC/RNC向MSC发送切换请求消息，例如：Handover CS to VoIP bearer。Step 506, GERAN/UTRAN access network element BSC/RNC sends a handover request message to MSC, for example: Handover CS to VoIP bearer.

步骤507，MSC向HSS发送IWF地址请求消息，例如：IWF Request，其中包括该MSC的MSC ID与UE用户的IMSI，向HSS请求UE注册的IWF地址信息。Step 507, the MSC sends an IWF address request message to the HSS, for example: IWF Request, which includes the MSC ID of the MSC and the IMSI of the UE user, and requests the HSS for the IWF address information registered by the UE.

步骤508，HSS向MSC返回IWF地址响应消息，例如：IWF Response（IWF ID，IMSI），向MSC返回UE注册的IWF地址信息。Step 508, the HSS returns an IWF address response message to the MSC, for example: IWF Response (IWF ID, IMSI), and returns the IWF address information registered by the UE to the MSC.

步骤509，MSC根据服务IWF的相关信息与IWF之间的对应关系信息，寻址UE的服务IWF，并向该服务IWF发送切换请求消息。In step 509, the MSC addresses the serving IWF of the UE according to the corresponding information about the serving IWF and the IWF, and sends a handover request message to the serving IWF.

图7为本发明MSC寻址UE的服务IWF，并发送切换请求消息又一个实施例的流程图。该实施例中，IWF将自己注册到HSS中，HSS可以将IWF地址作为签约信息主动插播给MSC。如图7所示，该实施例包括以下步骤：FIG. 7 is a flow chart of another embodiment of the present invention in which the MSC addresses the serving IWF of the UE and sends a handover request message. In this embodiment, the IWF registers itself in the HSS, and the HSS can actively insert the IWF address as subscription information to the MSC. As shown in Figure 7, this embodiment comprises the following steps:

步骤601，服务IWF接收UE发送的第一注册请求消息，例如：UE-IWFREGISTER REQUEST。Step 601, the serving IWF receives the first registration request message sent by the UE, for example: UE-IWFREGISTER REQUEST.

步骤602，服务IWF向UE的HSS发送第四注册请求消息，例如：Update Location Request。第四注册请求消息中包括服务IWF的相关信息，例如：IWF ID，根据该IWF ID，可以寻址相应的IWF。另外，第四注册请求消息还包括UE用户的IMSI。Step 602, the serving IWF sends a fourth registration request message, for example: Update Location Request, to the HSS of the UE. The fourth registration request message includes relevant information of the serving IWF, for example: IWF ID, and the corresponding IWF can be addressed according to the IWF ID. In addition, the fourth registration request message also includes the IMSI of the UE user.

步骤603，HSS对服务IWF进行注册，并向服务IWF返回注册响应消息。In step 603, the HSS registers with the serving IWF, and returns a registration response message to the serving IWF.

步骤604，服务IWF向UE返回注册响应消息，例如：GA-RCREGISTER ACCEPT，注册响应消息中包含IWF系统信息。Step 604, the serving IWF returns a registration response message to the UE, for example: GA-RCREGISTER ACCEPT, and the registration response message includes IWF system information.

步骤605，HSS在服务IWF的相关信息更新时，向MSC插入UE的签约数据，该签约数据包括更新的服务IWF的相关信息。Step 605, when the relevant information of the serving IWF is updated, the HSS inserts the subscription data of the UE into the MSC, and the subscription data includes the updated relevant information of the serving IWF.

IWF信息可以作为UE的签约数据，当HSS发现签约数据改变，也即：IWF信息更新时，例如：步骤602中，服务IWF发送注册请求消息时，HSS向已经完成注册的服务UE的网元，例如：MSC，插入签约数据携带所关联的IWF地址信息。The IWF information can be used as the subscription data of the UE. When the HSS finds that the subscription data has changed, that is, when the IWF information is updated, for example: in step 602, when the serving IWF sends a registration request message, the HSS sends a registration request to the network element serving the UE that has completed registration. For example: MSC, insert the subscription data to carry the associated IWF address information.

步骤606，MSC向HSS回复响应消息。In step 606, the MSC replies a response message to the HSS.

其中，步骤605-606与步骤603-604可以不按照上述时间顺序执行，步骤605-606也可以与步骤603-604同时执行或先于步骤603-604执行。Wherein, steps 605-606 and steps 603-604 may not be performed in the above chronological order, and steps 605-606 may also be performed simultaneously with steps 603-604 or performed prior to steps 603-604.

步骤607，MSC根据服务IWF的相关信息与IWF之间的对应关系信息，寻址更新的服务IWF的相关信息对应的UE的服务IWF。In step 607, the MSC addresses the serving IWF of the UE corresponding to the updated serving IWF related information according to the corresponding relationship information between the serving IWF related information and the IWF.

其中，步骤607也可以与步骤606同时执行或先于步骤606执行。Wherein, step 607 may also be performed simultaneously with step 606 or performed prior to step 606 .

图8为本发明通信业务切换处理方法另一个实施例的流程图。该实施例的通信业务切换处理方法以语音业务为例进行说明，对于其它业务仍然适用。如图8所示，其包括以下步骤：Fig. 8 is a flow chart of another embodiment of the communication service switching processing method of the present invention. The communication service switching processing method in this embodiment is described by taking the voice service as an example, and it is still applicable to other services. As shown in Figure 8, it includes the following steps:

步骤701，UE通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到UE的MME。其中的IWF即为UE的服务IWF，MME即为UE的源服务MME。In step 701, the UE registers with the IWF through GERAN/UTRAN, and registers with the UE's MME through the serving IWF. The IWF is the serving IWF of the UE, and the MME is the source serving MME of the UE.

具体地，该步骤701可以通过图3或图4所示实施例的流程实现。Specifically, step 701 may be implemented through the process of the embodiment shown in FIG. 3 or FIG. 4 .

步骤702，UE向GERAN/UTRAN的接入网网元BSC/RNC，即：源接入网网元BSC/RNC，上报切换测量报告Measurement Reports，该切换测量报告中包括E-UTRAN的测量信息与UE注册的服务IWF的测量信息。Step 702, the UE reports the handover measurement report Measurement Reports to the access network element BSC/RNC of GERAN/UTRAN, that is, the source access network element BSC/RNC, the handover measurement report includes the measurement information of E-UTRAN and Measurement information of the serving IWF registered by the UE.

步骤703，源接入网网元BSC/RNC根据E-UTRAN的测量信息与UE注册的服务IWF的测量信息决策发起切换流程。Step 703, the source access network element BSC/RNC decides to initiate a handover process according to the measurement information of the E-UTRAN and the measurement information of the serving IWF registered with the UE.

步骤704，源接入网网元BSC/RNC向MSC发送切换请求消息Handover Required，通知MSC进行CS域切换。Step 704, the source access network element BSC/RNC sends a handover request message Handover Required to the MSC, notifying the MSC to perform CS domain handover.

步骤705，MSC寻址UE的服务IWF，将其作为目标接入网网元，向该服务IWF发送切换请求消息Handover Request，通知该服务IWF准备资源。切换请求消息中包括CS域切换信息与E-UTRAN中目标接入网网元ID信息。Step 705, the MSC addresses the serving IWF of the UE, takes it as a target access network element, sends a handover request message Handover Request to the serving IWF, and notifies the serving IWF to prepare resources. The handover request message includes CS domain handover information and target access network element ID information in E-UTRAN.

步骤706，服务IWF根据目标接入网网元ID获知切换的目标网络是E-UTRAN，根据之前记录的UE的源服务MME信息，向该源服务MME发送切换请求消息Handover Required。Step 706: The serving IWF learns that the target network of the handover is E-UTRAN according to the network element ID of the target access network, and sends a handover request message Handover Required to the source serving MME according to the UE's source serving MME information recorded previously.

根据本发明的一个实施例，服务IWF向该源服务MME发送切换请求消息时，若UE在E-UTRAN网络中没有建立eNB与源服务MME之间的信令连接S1连接时，服务IWF首先触发S1连接建立流程建立S1连接，然后发送切换请求消息给源服务MME。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 has not established 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 procedure establishes the S1 connection, and then sends a handover request message to the source serving MME.

步骤707，源服务MME向目标MME发送转发重置请求消息ForwardRelocation Request，将UE的上下文传递给目标MME。Step 707, the source serving MME sends a ForwardRelocation Request message to the target MME, and transfers the context of the UE to the target MME.

步骤708，根据UE的位置等相关信息与之前服务的S-GW的负载、能量等相关信息，如果之前服务的S-GW无法继续服务，目标MME重新选择S-GW，并向选择的S-GW发送创建承载请求消息Create BearerRequest。Step 708: According to the relevant information such as the location of the UE and 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 sends a request to the selected S-GW. The GW sends a create bearer request message Create BearerRequest.

步骤709，选择的S-GW向目标MME返回创建承载响应消息CreateBearer Response，与目标MME之间建立承载。Step 709, the selected S-GW returns a create bearer response message CreateBearer Response to the target MME, and establishes a bearer with the target MME.

步骤710，目标MME向E-UTRAN中的目标eNB发送切换请求消息Handover Request。Step 710, the target MME sends a handover request message Handover Request to the target eNB in the E-UTRAN.

步骤711，目标eNB向目标MME回复切换请求确认消息HandoverRequest Ack。Step 711, the target eNB replies a handover request confirmation message HandoverRequest Ack to the target MME.

在步骤710-711目标MME与目标eNB的交互过程中，目标MME还根据源服务MME传递过来的UE上下文，通知eNB建立承载。During the interaction between the target MME and the target eNB in steps 710-711, the target MME also notifies the eNB to establish a bearer according to the UE context delivered by the source serving MME.

步骤712，目标MME向源服务MME回复转发重置响应消息ForwardRelocation Response，通知目标网络E-UTRAN中的切换准备阶段完成。Step 712: The target MME replies a ForwardRelocation Response message to the source serving MME, notifying the target network that the handover preparation phase in the E-UTRAN is completed.

步骤713，源服务MME向服务IWF发送切换命令Handover Command，通知目标网络E-UTRAN中的切换准备阶段完成。Step 713, the source serving MME sends a Handover Command to the serving IWF, notifying the target network E-UTRAN that the handover preparation phase is completed.

步骤714，服务IWF在该服务IWF与MSC之间完成资源准备，向MSC回复切换请求确认消息Handover Ack。In step 714, the serving IWF completes resource preparation between the serving IWF and the MSC, and returns a handover request acknowledgment message Handover Ack to the MSC.

步骤715，MSC向源接入网网元BSC/RNC回复切换命令HandoverCommand，通知切换准备阶段完成。In step 715, the MSC replies the handover command HandoverCommand to the network element BSC/RNC of the source access network, notifying the completion of the handover preparation phase.

步骤716，源接入网网元BSC/RNC向UE发送切换命令HandoverCommand，通知UE切换到目标网络。该切换命令消息中携带目标网络E-UTRAN的相关信息。Step 716, the source access network element BSC/RNC sends a handover command HandoverCommand to the UE, notifying the UE to handover to the target network. The handover command message carries relevant information of the target network E-UTRAN.

步骤717，UE根据目标网络E-UTRAN的相关信息，执行E-UTRAN网络接入过程，之后，向目标接入网网元eNB发送切换完成消息HandoverComplete。Step 717, the UE executes the E-UTRAN network access process according to the relevant information of the target network E-UTRAN, and then sends a handover complete message HandoverComplete to the network element eNB of the target access network.

步骤718，目标接入网网元eNB向目标MME发送切换完成通知消息Handover Notify。Step 718, the network element eNB of the target access network sends a Handover Notify message to the target MME.

步骤719，目标MME向源服务MME发送转发重置完成消息ForwardRelocation Complete，通知源服务MME，UE已经接入E-UTRAN。Step 719, the target MME sends a ForwardRelocation Complete message to the source serving MME, notifying the source serving MME that the UE has accessed the E-UTRAN.

步骤720，源服务MME向目标MME回复转发重置完成确认消息Forward Relocation Complete Ack。In step 720, the source serving MME replies a Forward Relocation Complete Ack message to the target MME.

步骤721，目标MME向S-GW发送更新承载请求消息Update BearerRequest。Step 721, the target MME sends an update bearer request message Update BearerRequest to the S-GW.

步骤722，S-GW向P-GW发送更新承载请求消息Update DedicatedBearer Request。In step 722, the S-GW sends an update bearer request message Update Dedicated Bearer Request to the P-GW.

步骤723，P-GW与S-GW之间更新承载，并向S-GW返回更新承载响应消息Update Dedicated Bearer Response。In step 723, the bearer is updated between the P-GW and the S-GW, and an update bearer response message Update Dedicated Bearer Response is returned to the S-GW.

步骤724，S-GW向目标MME回复更新承载响应消息Update DedicatedBearer Response。In step 724, the S-GW replies an update bearer response message Update Dedicated Bearer Response to the target MME.

步骤725，UE发起跟踪区更新流程TAU Procedure，完成目标MME到HSS的注册。Step 725, the UE initiates the tracking area update procedure TAU Procedure, and completes the registration of the target MME to the HSS.

步骤726，UE向服务IWF回复切换完成消息Handover Complete。In step 726, the UE replies a Handover Complete message to the serving IWF.

步骤727，服务IWF向MSC回复切换完成消息Handover Complete，语音业务流从源侧切换到服务IWF，即：MSC将语音业务流传递到服务IWF。In step 727, the serving IWF replies to the MSC with a Handover Complete message, and the voice service flow is switched from the source side to the serving IWF, that is, the MSC transfers the voice service flow to the serving IWF.

步骤728，服务IWF触发语音业务流的承载建立流程。In step 728, the serving IWF triggers the bearer establishment process of the voice service flow.

步骤729，服务IWF向策略与计费规则功能实体（Policy and ChargingRules Function，以下简称：PCRF）提供语音业务的相关信息，触发PCRF发起语音业务的专有承载激活流程Dedicated Bearer Activation Procedure。PCRF向P-GW提供策略和计费控制（Policy Charging Control，以下简称：PCC）信息，P-GW发起专有承载建立流程.专有承载建立完成，语音业务流从GERAN/UTRAN的CS域切换到E-UTRAN。In step 729, the serving IWF provides relevant information of the voice service to the Policy and Charging Rules Function (Policy and Charging Rules Function, PCRF for short), and triggers the PCRF to initiate the Dedicated Bearer Activation Procedure of the voice service. PCRF provides policy and charging control (Policy Charging Control, hereinafter referred to as: PCC) information to P-GW, and P-GW initiates the dedicated bearer establishment process. After the dedicated bearer is established, the voice service flow is switched from the CS domain of GERAN/UTRAN to E-UTRAN.

本发明图2至图8所示的实施例中，主要处理了CS域业务的切换。如果在CS域业务切换的同时，还有正在进行的PS域业务需要从GERAN/UTRAN切换到E-UTRAN，即：完成GERAN/UTRAN中同时进行的CS域和PS域业务向E-UTRAN的切换。根据图2至图8所示的实施例，可以将正在进行的PS域业务切断或者挂起，即：优先保证CS域业务的顺利切换。In the embodiments shown in FIG. 2 to FIG. 8 of the present invention, switching of CS domain services is mainly handled. If there is an ongoing PS domain service switching from GERAN/UTRAN to E-UTRAN at the same time as CS domain service switching, that is: complete the simultaneous switching of CS domain and PS domain services in GERAN/UTRAN to E-UTRAN . According to the embodiments 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 can be guaranteed first.

根据本发明的另一个实施例，如果同时有CS域业务与PS域业务需要从GERAN/UTRAN切换到E-UTRAN，在图1所示的实施例的步骤102中，切换请求消息中还包括PS域切换信息，与UE注册的SGSN地址信息或触发信息，SGSN地址信息或触发信息用于触发源服务MME从SGSN获取UE的上下文。相应的业务流为CS域业务流与PS域业务流。由于GERAN/UTRAN的接入网网元只向MSC发送切换请求，而不向SGSN发送切换请求，GERAN/UTRAN的接入网网元感知切换的目标网络是E-UTRAN时，只触发CS域的切换。后续步骤103与步骤104中，MSC与服务IWF不解析PS域切换信息，主要是通过服务IWF传递给源服务MME。相应的，步骤104中，指示源服务MME执行CS域业务向E-UTRAN的切换流程时，还包括：指示源服务MME执行PS域业务向E-UTRAN的切换流程。According to another embodiment of the present invention, if there are both CS domain services and PS domain services that need to be switched from GERAN/UTRAN to E-UTRAN, instep 102 of the embodiment shown in Figure 1, the switching request message also includes PS Domain switching information, SGSN address information or trigger information registered with the UE, SGSN address information or trigger information is used to trigger the source serving MME to obtain the UE context from the SGSN. Corresponding service flows are CS domain service flow and PS domain service flow. Since the GERAN/UTRAN access network element only sends a handover request to the MSC, but not to the SGSN, when the GERAN/UTRAN access network element perceives that the target network of the handover is E-UTRAN, it only triggers the CS domain switch. Insubsequent steps 103 and 104, the MSC and the serving IWF do not analyze the PS domain handover information, but mainly transmit it to the source serving MME through the serving IWF. Correspondingly, instep 104, when instructing the source serving MME to perform the handover procedure of the CS domain service to the E-UTRAN, it also includes: instructing the source serving MME to perform the handover procedure of the PS domain service to the E-UTRAN.

具体地，指示源服务MME执行PS域业务向E-UTRAN的切换流程包括：服务IWF向源服务MME转发切换请求消息；源服务MME寻址SGSN，并根据SGSN地址信息或触发信息，从SGSN获取UE的上下文；源服务MME执行PS域业务向E-UTRAN的切换流程。Specifically, instructing the source serving MME to execute the handover process of the PS domain service to E-UTRAN includes: the serving IWF forwards the handover request message to the source serving MME; the source serving MME addresses the SGSN, and obtains the The context of the UE; the source serving MME executes the handover process from the PS domain service to the E-UTRAN.

另外，如果源服务MME没有UE注册的SGSN地址信息，根据触发信息从SGSN获取UE的上下文之前，还可以包括：服务IWF获取UE注册的SGSN地址信息，并将该SGSN地址信息提供给源服务MME；或者，源服务MME从HSS获取UE注册的SGSN地址信息；或者，UE通过NAS信令，将UE注册的SGSN地址信息发送给源服务MME。其中的NAS信令具体为附着请求消息、TAU请求消息或PDN连接请求消息。In addition, if the source serving MME does not have the SGSN address information registered by the UE, before obtaining the context of the UE from the SGSN according to the trigger information, it may also include: the serving IWF obtains the SGSN address information registered by the UE, and provides the SGSN address information to the source serving MME ; or, the source serving MME acquires the SGSN address information registered by the UE from the HSS; or, the UE sends the SGSN address information registered by the UE to the source serving MME through NAS signaling. The NAS signaling is specifically an attach request message, a TAU request message or a PDN connection request message.

具体地，服务IWF获取UE注册的SGSN地址信息可以是：UE在与服务IWF的信息交互过程中，向服务IWF发送SGSN地址信息；或者，UE在接收到SGSN重新分配的分组临时移动用户身份标识（PacketTemporary Mobile Subscriber Identity，以下简称：P-TMSI）与路由区标识（Routing Area Identity，以下简称：RAI）时，向服务IWF发送SGSN地址信息。Specifically, the serving IWF obtains the SGSN address information registered by the UE may be: the UE sends the SGSN address information to the serving IWF during the information interaction process with the serving IWF; (PacketTemporary Mobile Subscriber Identity, hereinafter referred to as: P-TMSI) and routing area identity (Routing Area Identity, hereinafter referred to as: RAI), send SGSN address information to the serving IWF.

图9为本发明服务IWF向源服务MME发送切换请求消息一个实施例的流程图。如图9所示，该实施例包括以下步骤：Fig. 9 is a flowchart of an embodiment of sending a handover request message from the serving IWF to the source serving MME according to the present invention. As shown in Figure 9, this embodiment comprises the following steps:

步骤801，服务IWF向源服务MME发送切换请求消息，该切换请求消息中包括CS域切换信息、PS域切换信息、E-UTRAN中目标接入网网元ID信息，与UE注册的SGSN地址信息或触发信息，SGSN地址信息或触发信息用于触发源服务MME从SGSN获取UE的上下文。Step 801, the serving IWF sends a handover request message to the source serving MME, the handover request message includes CS domain handover information, PS domain handover information, target access network element ID information in E-UTRAN, and SGSN address information registered by the UE Or trigger information, the SGSN address information or trigger information is used to trigger the source serving MME to obtain the context of the UE from the SGSN.

步骤802，源服务MME寻址UE的服务SGSN，并向该服务SGSN发送UE上下文请求消息Context Request，请求UE的上下文。Step 802, the source serving MME addresses the serving SGSN of the UE, and sends a UE context request message Context Request to the serving SGSN, requesting the context of the UE.

步骤803，服务SGSN向源服务MME返回UE上下文响应消息ContextResponse，其中包括UE的上下文。Step 803, the serving SGSN returns a UE context response message ContextResponse to the source serving MME, which includes the UE context.

步骤804，源服务MME向服务SGSN返回UE上下文确认消息ContextAck。Step 804, the source serving MME returns a UE context confirmation message ContextAck to the serving SGSN.

具体地，步骤802中，源服务MME可以通过以下三种方式寻址UE的服务SGSN：Specifically, in step 802, the source serving MME can address the UE's serving SGSN in the following three ways:

第一种方式是：服务IWF获取UE注册的SGSN地址信息，并将该SGSN地址信息提供给源服务MME。UE可以在与IWF的交互过程中，将注册的SGSN地址信息提供给IWF。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 serving MME. During the interaction with the IWF, the UE may provide the registered SGSN address information to the IWF.

作为一个实施例，在UE向IWF注册或者注册更新的过程中，例如：UE初次注册到IWF或者服务IWF改变，UE重新注册到新IWF的过程中，UE可以在向IWF发起注册流程的UE-IWF DISCOVERY REQUEST消息或者UE-IWF REGISTER REQUEST消息或者UE-IWF REGISTERUPDATE UPLINK消息中携带SGSN地址信息。或者，在UE与IWF的其它交互过程中，将带SGSN地址信息携带在相关消息中发送给IWF。As an embodiment, during the process of the UE registering with the IWF or updating the registration, for example: the UE registers with the IWF for the first time or the serving IWF changes, and the UE re-registers with the new IWF. The IWF DISCOVERY REQUEST message or the UE-IWF REGISTER REQUEST message or the UE-IWF REGISTERUPDATE UPLINK message carries the SGSN address information. Or, during other interaction processes between the UE and the IWF, send the related message with the SGSN address information to the IWF.

作为另一个实施例，若UE已经注册到服务IWF，如果UE接收到SGSN重新分配的P-TMSI和RAI信息，例如：SGSN改变时，UE发送消息，例如：UE-IWF REGISTER UPDATE UPLINK，给服务IWF，该消息中携带更新的SGSN地址信息。即：UE在GERAN/UTRAN中每次执行RAU时，UE向服务IWF提供SGSN地址信息P-TMSI和RAI信息。As another embodiment, if the UE has registered to the serving IWF, if the UE receives the P-TMSI and RAI information reassigned by the SGSN, for example: when the SGSN changes, the UE sends a message, such as: UE-IWF REGISTER UPDATE UPLINK, to the serving IWF, the message carries updated SGSN address information. That is: every time the UE executes RAU in GERAN/UTRAN, the UE provides SGSN address information P-TMSI and RAI information to the serving IWF.

作为又一个实施例，UE也可以不采用信令交互的方式，而是将服务IWF作为目的地，将SGSN地址信息放置在一个数据包中传递给服务IWF。IWF解析该数据包可以得到服务SGSN地址信息。As yet another embodiment, instead of using signaling interaction, the UE may take the serving IWF as the destination, put the SGSN address information in a data packet and transmit it to the serving IWF. The IWF parses the data packet to obtain the address information of the serving SGSN.

第二种方式是：当源服务MME需要获取UE注册的SGSN地址信息时，源服务MME从HSS获取UE注册的SGSN地址信息。The second way is: when the source serving MME needs to obtain the SGSN address information registered by the UE, the source serving MME obtains the SGSN address information registered by the UE from the HSS.

具体地，源服务MME可以向HSS发送SGSN地址请求消息SGSNRequest，请求获取UE注册的SGSN地址信息。SGSN地址请求消息中包括源服务MME ID与UE用户的IMSI。HSS接收到SGSN地址请求消息后，向源服务MME返回SGSN地址响应消息SGSN Response，返回UE注册的SGSN地址信息，其中包括SGSN ID与UE用户的IMSI。Specifically, the source serving MME may send an SGSN address request message SGSNRequest to the HSS, requesting to obtain the SGSN address information registered by the UE. The SGSN address request message includes the source serving MME ID and the IMSI of the UE user. After receiving the SGSN address request message, the HSS returns the SGSN address response message SGSN Response to the source serving MME, and returns the SGSN address information registered by the UE, including the SGSN ID and the IMSI of the UE user.

第三种方式是：UE通过NAS信令，将UE注册的SGSN地址信息发送给源服务MME。其中的NAS信令具体为附着请求消息Attach Request、TAU请求消息TAU Request或PDN连接请求消息PDN ConnectivityRequest等。另外，还可以通过增加一条新NAS消息来传递UE注册的SGSN地址信息。如果UE接收到SGSN重新分配的P-TMSI和RAI信息，例如：SGSN改变的情况，UE可以在NAS消息中携带更新的SGSN地址信息发送给源服务MME。即：UE在GERAN/UTRAN中每次执行RAU时，向源服务MME提供SGSN地址信息P-TMSI和RAI信息。The third way is: the UE sends the SGSN address information registered by the UE to the source serving MME through NAS signaling. The NAS signaling specifically includes an Attach Request message, a TAU request message TAU Request, or a PDN connection request message PDN ConnectivityRequest, etc. 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 reassigned by the SGSN, for example, when the SGSN changes, the UE may carry the updated SGSN address information in the NAS message and send it to the source serving MME. Namely: UE provides SGSN address information P-TMSI and RAI information to source serving MME each time it executes RAU in GERAN/UTRAN.

图10为本发明IWF一个实施例的结构示意图。该实施例的IWF可作为UE的服务IWF，实现本发明上述实施例中服务IWF的相应功能。如图10所示，该实施例的IWF包括注册接收单元901、转发单元902、切换触发单元903等。Fig. 10 is a schematic structural diagram of an embodiment of the IWF of the present invention. The IWF in this embodiment can be used as the serving IWF of the UE to implement the corresponding functions of the serving IWF in the foregoing embodiments of the present invention. As shown in FIG. 10 , the IWF of this embodiment includes aregistration receiving unit 901 , aforwarding unit 902 , ahandover triggering unit 903 and the like.

其中，注册接收单元901，用于接收用户终端在源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务IWF的注册；Wherein, theregistration receiving unit 901 is configured to receive the first registration request message sent by the user terminal in the source network, and complete the registration of the user terminal to the service IWF of the user terminal;

转发单元902，用于接收所述用户终端在源网络发送的第二注册请求消息，并将所述第二注册请求消息转发到所述用户终端的源服务MME，以使所述用户终端完成到所述源服务MME的注册；Theforwarding unit 902 is configured to receive the second registration request message sent by the user terminal on the source network, and forward the second registration request message to the source serving MME of the user terminal, so that the user terminal completes the registration of said source serving MME;

切换触发单元903，用于接收用户终端的在源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME，以使所述源服务MME执行切换流程，将所述用户终端切换到目标网络。Thehandover triggering unit 903 is configured to receive a handover request message of the user terminal on the source network, and forward the handover request message to the source serving MME, so that the source serving MME performs a handover process, and the user terminal Switch to the target network.

在本发明的另外一个实施例中，所述转发单元，还用于确定所述用户终端的源服务IWF，在所述第二注册请求消息中未包括MME信息时，从MME列表中选择满足预设条件的MME作为所述源服务MME；或者In another embodiment of the present invention, the forwarding unit is further configured to determine the source serving IWF of the user terminal, and when the second registration request message does not include MME information, select an IWF from the MME list that meets the predetermined requirements. set the conditional MME as the source serving MME; or

在所述第二注册请求消息中包括MME信息时，查询所述第二注册请求消息中包括的MME信息所标识的MME是否存在于所述MME列表中；若存在于所述MME列表中，则选择所述第二注册请求消息中包括的MME信息标识的MME作为所述源服务MME；若不存在于所述MME列表中，从MME列表中选择满足预设条件的MME作为所述源服务MME。其中所述MME列表可以保存在服务IWF上。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, then Select 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, select an MME that meets preset conditions from the MME list as the source serving MME . The MME list may be stored on the service IWF.

在本发明的另外一个实施例中，所述服务IWF还可以包括：In another embodiment of the present invention, the service IWF may also include:

注册请求单元，还用于在所述注册接收单元完成用户终端的注册后，发送第四注册请求消息到用户终端的归属用户服务器HSS，请求完成到所述HSS的注册。The registration request 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 the registration of the user terminal, requesting to complete the registration to the HSS.

上述实施例中，源网络可以是GERAN、UTRAN等，目标网络可以是E-UTRAN等。UE可以通过GERAN/UTRAN注册到IWF，并通过该服务IWF注册到服务MME，这样，UE的CS域业务需要从GERAN/UTRAN切换到E-UTRAN时，服务IWF可以作为E-UTRAN中的目标接入网网元，根据UE注册到服务MME的过程中存储的源服务MME信息，指示服务MME执行CS域业务向E-UTRAN的切换流程，解决了E-UTRAN中的目标接入网网元eNB无法处理CS域信令流程问题，保障了GERAN/UTRAN到E-UTRAN的CS域业务切换的正常进行，从而保证了用户的通信业务质量。In the above embodiments, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN, etc. The UE can register with the IWF through GERAN/UTRAN, and register with the serving MME through the serving IWF. In this way, when the CS domain service of the UE needs to be switched from GERAN/UTRAN to E-UTRAN, the serving IWF can be used as the target in E-UTRAN. The incoming network element, according to the source serving MME information stored in the process of UE registration with the serving MME, instructs the serving MME to execute the handover process of CS domain services to E-UTRAN, which solves the problem of the target access network element eNB in E-UTRAN It cannot deal with the CS domain signaling process problem, which ensures the normal progress of the CS domain service handover from GERAN/UTRAN to E-UTRAN, thereby ensuring the quality of communication services for users.

图11为本发明MSC一个实施例的结构示意图，其包括接收单元1001、确定单元1002和发送单元1003，其中：Figure 11 is a schematic structural diagram of an embodiment of the MSC of the present invention, which includes areceiving unit 1001, a determiningunit 1002, and a sendingunit 1003, wherein:

接收单元1001，用于接收源网络的接入网元发送的用户终端切换请求消息；The receivingunit 1001 is configured to receive a user terminal handover request message sent by an access network element of the source network;

确定单元1002，用于根据所述接收单元1001接收到的切换请求消息确定所述终端的服务互通功能实体IWF；A determiningunit 1002, configured to determine a service interworking function entity IWF of the terminal according to the handover request message received by the receivingunit 1001;

发送单元1003，用于将所述切换请求消息发送给所述确定单元1002确定的服务IWF。The sendingunit 1003 is configured to send the handover request message to the serving IWF determined by the determiningunit 1002 .

在本发明的另外一个实施例中，当所述切换请求消息中包括服务IWF的相关信息时，所述确定单元1002在所述接收单元接收到接入网元发送的用户终端切换请求消息后，根据所述服务IWF的相关信息向HSS查询服务IWF的地址；或者In another embodiment of the present invention, when the handover request message includes information about the serving IWF, the determiningunit 1002, after the receiving unit receives the user terminal handover request message sent by the access network element, Querying the HSS for the address of the serving IWF according to the relevant information of the serving IWF; or

当服务IWF的相关信息更新时，HSS将包含所述服务IWF的相关信息的签约数据发送给所述移动交换中心MSC，所述确定单元1002在所述接收单元接收到接入网元发送的用户终端切换请求消息后，根据服务IWF的相关信息确定确定所述用户终端的服务IWF。When the relevant information of the serving IWF is updated, the HSS sends the subscription data containing the relevant information of the serving IWF to the mobile switching center MSC, and the determiningunit 1002 receives the user information sent by the access network element at the receiving unit After the terminal switches the request message, it determines the serving IWF of the user terminal according to the relevant information of the serving IWF.

上述实施例中，源网络可以是GERAN、UTRAN等，目标网络可以是E-UTRAN等。本发明实施例所提供的MSC，能将源网络中用户终端的切换请求转发给服务IWF处理，解决了E-UTRAN中的目标接入网网元eNB无法处理CS域信令流程问题，保障了GERAN/UTRAN到E-UTRAN的CS域业务切换的正常进行，从而保证了用户的通信业务质量。In the above embodiments, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN, etc. 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 serving IWF for processing, which solves the problem that the target access network element eNB in the E-UTRAN cannot handle the CS domain signaling process, and ensures The CS domain service switching from GERAN/UTRAN to E-UTRAN is normally carried out, thereby ensuring the communication service quality of users.

图12为本发明MME一个实施例的结构示意图，其包括接收单元1101和切换单元1102，其中：Fig. 12 is a schematic structural diagram of an embodiment of the MME of the present invention, which includes areceiving unit 1101 and aswitching unit 1102, wherein:

接收单元1101，用于接收用户终端的服务互通功能实体IWF发送的用户终端的切换请求消息；The receivingunit 1101 is configured to receive the handover request message of the user terminal sent by the service interworking function entity IWF of the user terminal;

切换单元1002，用于将用户终端从源网络切换到目标网络。Theswitching unit 1002 is configured to switch the user terminal from the source network to the target network.

在本发明的另外一个实施例中，所述移动性管理实体还包括：In another embodiment of the present invention, the mobility management entity further includes:

第一建立单元，用于建立用户终端到互通功能实体IWF的互联网协议IP通道。The first establishing unit is configured to establish an Internet protocol IP channel from the user terminal to the interworking function entity IWF.

同时，在本发明的另外一个实施例中，所述移动性管理实体还包括：Meanwhile, in another embodiment of the present invention, the mobility management entity further includes:

第二建立单元，用于确定所述源服务MME与所述目标接入网网元之间没有建立S1连接时，建立与所述目标接入网网元之间的S1连接。The second establishing unit is configured to establish an S1 connection with the network element of the target access network when it is determined that an S1 connection has not been established between the source serving MME and the network element of the target access network.

获取单元，用于获取通用分组无线业务服务支持节点SGSN的地址信息，并从SGSN上获取所述终端用户的上下文。The acquiring unit is configured to acquire the address information of the serving general packet radio service support node SGSN, and acquire the context of the terminal user from the SGSN.

上述实施例中，源网络可以是GERAN、UTRAN等，目标网络可以是E-UTRAN等。本发明实施例所提供的移动管理实体能接收源网络中服务IWF发送的切换指示，将所述用户终端的业务从源网络切换到目标网络，解决了E-UTRAN中的目标接入网网元eNB无法处理CS域信令流程问题，保障了GERAN/UTRAN到E-UTRAN的CS域业务切换的正常进行，从而保证了用户的通信业务质量。In the above embodiments, the source network may be GERAN, UTRAN, etc., and the target network may be E-UTRAN, etc. The mobility management entity provided by the embodiment of the present invention can receive the switching instruction 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, which solves the problem of the network element of the target access network in E-UTRAN The eNB cannot handle the CS domain signaling process problem, which ensures the normal progress of the CS domain service handover from GERAN/UTRAN to E-UTRAN, thereby ensuring the communication service quality of users.

图13为本发明网络系统一个实施例的结构示意图，其包括移动交换中心MSC1201、用户终端的服务互通功能实体IWF1202和用户终端的源服务移动性管理实体1203，其中Fig. 13 is a schematic structural diagram of an embodiment of the network system of the present invention, which includes a mobile switching center MSC1201, a service interworking function entity IWF1202 of the user terminal, and a source service mobility management entity 1203 of the user terminal, wherein

所述MSC1201，用于接收源网络的接入网元发送的用户终端的切换请求消息，根据所述切换请求消息确定所述终端的服务IWF1202，并将所述切换请求消息发送给所述确定的服务IWF1202；The MSC1201 is configured to receive the handover request message of the user terminal sent by the access network element of the source network, determine the serving IWF1202 of the terminal according to the handover request message, and send the handover request message to the determined service IWF1202;

所述服务IWF1202，用于接收用户终端在源网络发送的第一注册请求消息，完成所述用户终端到所述用户终端的服务IWF1202的注册；接收所述用户终端在源网络发送的第二注册请求消息，并将所述第二注册请求消息转发到所述源服务MME1203，以使所述用户终端完成到所述源服务MME1203的注册；接收用户终端的在源网络的切换请求消息，并将所述切换请求消息转发给所述源服务MME1203，以使所述源服务MME1203执行切换流程，将所述用户终端切换到目标网络；The service IWF1202 is configured to receive the first registration request message sent by the user terminal on the source network, and complete the registration from the user terminal to the service IWF1202 of the user terminal; receive the second registration request message sent by the user terminal on the source network request message, and forward the second registration request message to the source serving MME1203, so that the user terminal completes the registration to the source serving MME1203; receive the handover request message of the user terminal in the source network, and send Forwarding the handover request message to the source serving MME1203, so that the source serving MME1203 executes a handover process to handover the user terminal to the target network;

所述源服务MME1203，用于接收服务IWF1202发送的用户终端的切换请求消息，将用户终端切换从源网络切换到目标网络。The source serving MME1203 is configured to receive the handover request message of the user terminal sent by the serving IWF1202, and handover the user terminal from the source network to the target network.

另外，所述源服务IWF1202还用于确定所述用户终端的服务IWF。In addition, the source serving IWF 1202 is also used to determine the serving IWF of the user terminal.

在本发明的另外一个实施例中，当所述切换请求消息中包括CS域业务时，所述服务IWF确定所述源服务MME与所述目标接入网网元之间没有建立S1连接时，所述服务IWF触发所述源服务MME建立与所述目标接入网网元之间的S1连接。In another embodiment of the present invention, when the handover request message includes a CS domain service, and the serving IWF determines that no S1 connection is established between the source serving MME and the target access network element, The serving IWF triggers the source serving MME to establish an S1 connection with the target access network element.

本领域普通技术人员可以理解：实现上述方法实施例的全部或部分步骤可以通过程序指令相关的硬件来完成，前述的程序可以存储于一计算机可读取存储介质中，该程序在执行时，执行包括上述方法实施例的步骤；而前述的存储介质包括：ROM、RAM、磁碟或者光盘等各种可以存储程序代码的介质。Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

本发明实施例提供了通信业务，尤其是语音业务，从GERAN/UTRAN的CS域切换到E-UTRAN的处理方法，当用户在GERAN/UTRAN附着，通过GERAN/UTRAN完成到IWF的注册后，后续发生网络切换时，IWF作为目标接入网网元处理切换流程，解决了eNB无法处理CS域信令流程的问题，保障了GERAN/UTRAN到E-UTRAN的CS域切换的正常进行，保证了通信质量与用户的业务体验。进一步的，UE还可以通过服务IWF完成到MME的注册以及通过MME预先建立UE到IWF之间的传输通道。在后续的切换过程中，由于之前已经建立了UE到IWF之间的传输通道，服务IWF接收到MSC传递的CS域业务流后，可以顺利的将CS域业务流传递给UE，而不需要执行附着到EPS网络并在EPS网络建立UE到IWF之间的传输通道的流程，减少了CS域业务切换的时延，提高了通信质量与用户的业务体验。The embodiment of the present invention provides a communication service, especially a voice service, from the CS domain of GERAN/UTRAN to the processing method of E-UTRAN. When a network handover occurs, the IWF handles the handover process as the target access network element, which solves the problem that the eNB cannot handle the CS domain signaling process, ensures the normal progress of the CS domain handover from GERAN/UTRAN to E-UTRAN, and ensures communication Quality and user experience. Further, the UE can complete registration with the MME through the serving IWF and pre-establish a transmission channel between the UE and the IWF through the MME. In the subsequent handover process, since the transmission channel between the UE and the IWF has been established before, after the serving IWF receives the CS domain service flow delivered by the MSC, it can smoothly deliver the CS domain service flow to the UE without performing The process of attaching to the EPS network and establishing a transmission channel between the UE and the IWF on the EPS network reduces the delay of CS domain service handover and improves the communication quality and user experience.

最后所应说明的是：以上实施例仅用以说明本发明的技术方案，而非对本发明作限制性理解。尽管参照上述较佳实施例对本发明进行了详细说明，本领域的普通技术人员应当理解：其依然可以对本发明的技术方案进行修改或者等同替换，而这种修改或者等同替换并不脱离本发明技术方案的精神和范围。Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present invention, rather than limiting the understanding of the present invention. Although the present invention has been described in detail with reference to the above-mentioned preferred embodiments, those skilled in the art should understand that: it can still modify or replace the technical solution of the present invention, and such modification or replacement does not depart from the technology of the present invention. The spirit and scope of the programme.