CN102572785B - User's loaming method and ICS strengthen network - Google Patents

Abstract

The invention discloses a kind of user's loaming method, strengthen in network at ICS and set up BPF; Described method comprises: after Mobile Access Gateway controlling functions entity mAGCF receives the location update request message of user equipment (UE), when determining described UE for other network users, sends login request message to described BPF; After described BPF receives described login request message, the request message of the acquisition user data of the attaching position register HLR sent to belonging to described user is sent with Mobile solution agreement MAP message form; After described BPF receives the user data of described HLR transmission, send registration reply message to described mAGCF, described mAGCF sends position update response information to described UE.The present invention discloses a kind of ICS and strengthen network.Present invention achieves ICS and strengthen network to the compatibility of other network users, also can be realized the business in CS territory by IMS.

Description

User Roaming Method and ICS Enhanced Network

technical field

The present invention relates to a roaming technology in an IP Multimedia Subsystem (IMS, IP Multimedia Subsystem) network architecture, in particular to a user roaming method based on an IMS Centralized Service (ICS, IMS Centralized Service) and an ICS enhanced network.

Background technique

Internet Protocol (IP, Internet Protocol) Multimedia Subsystem (IMS, IP MultimediaCore Network Subsystem) is an IP-based network architecture proposed by the Third Generation Partnership Project (3GPP, 3rd Generation Partnership Project), which builds an open The flexible business environment supports multimedia applications and provides users with rich multimedia services.

IMS has nothing to do with access technology. It can provide services for general packet radio service (GPRS, General Packet Radio Service), wireless local area network (WLAN, Wireless Local Area Network) and other packet (PS, Packet Switching) access networks, and can also provide global Mobile cellular networks such as GSM (Global System for Mobile communications) and UMTS (Universal Mobile Telecommunications System) provide services.

Mobile networks such as GSM and UMTS adopt circuit switching technology, which is called a circuit (CS, Circuit Switched) domain, and can provide users with basic voice services and supplementary services based on voice services. When the CS domain accesses the IMS, it evolves into an access mode, and the service is completely provided by the IMS. This technology is called IMS Centralized Service (ICS, IMS Centralized Service).

Figure 1 is an architecture diagram of the IMS centralized control service, as shown in Figure 1, including: User Equipment (UE, User Equipment) 101, Global Mobile Communication System Radio Access Network (UTRAN, Universal MobileTelecommunication System Radio Access Network)/GSM EDGE Radio access network (GERAN, GSM EDGE Radio Access Network) 102, ICS mobile switching server (ICSMSC Server, ICS Mobile Switch Center Server) 103, circuit domain media gateway (CS-MGW, CS Media Gateway) 104, home user server (HSS, Home Subscriber Server) 105, call session control function entity (CSCF, Call Session Control Function) 106 and telephone application server (TAS, Telephony Application Server) 107; wherein,

UTRAN/GERAN 102, responsible for radio resource access control and management;

ICS MSC Server 103, in addition to completing the CS user equipment access, mobility management, and call control functions, also acts as a session initiation protocol (SIP, Session Initiation Protocol) user agent to realize the conversion between CS signaling and SIP messages, Access the IMS instead of the user.

CS-MGW 104 is responsible for providing media resources, and managing and controlling media resources;

HSS 105, used to save the user's subscription data and provide support for calls or sessions.

CSCF 106 is further divided into inquiring CSCF (I-CSCF, Interrogating CSCF) and service (S-CSCF, Serving CSCF). The I-CSCF interacts with the HSS, requesting the HSS to allocate an S-CSCF for the user, or query the S-CSCF where the user is located; the S-CSCF provides functions such as registration and call control for the user.

TAS 107 is used to handle traditional CS domain telephone services.

UE 101 accesses ICS MSC Server 103 through CS control signaling, ICS MSC Server acts as a user agent, replaces CS user equipment 101 to access CSCF 106 of the IMS network, and establishes a session connection with a remote user, and ICS MSC Server 103 controls The CS-MGW 104 completes the conversion between the media stream on the CS bearer and the media stream on the IP bearer, and establishes the media connection between the user equipment 101 and the remote user.

From the perspective of network development, it is recognized by the industry that the core network is eventually developed to be managed by the IMS. 3GPP formulated the ICS technology in version 8, and the CS network is connected to the IMS network through MSC Server enhancement. A key technology for the evolution from a CS network to an IMS network. However, the existing ICS technology does not consider reducing the cost of ICS MSC. The existing standard is only enhanced on the basis of the traditional mobile switching center (MSC, Mobile Switch Center) to support ICS service triggering. In fact, if the service Unified migration to the IMS network, the ICS MSC can be simplified to reduce the cost of the core network.

For this reason, the industry proposes an ICS enhanced network architecture to weaken MSC Server functions. Compared with traditional ICS, the solution CS network completely sinks to the access layer, so that the network structure is relatively simple and no longer depends on CS Core and No. 7 Signaling network.

Figure 2 is a schematic diagram of the ICS enhanced network architecture. As shown in Figure 2, on the basis of the structure shown in Figure 1, the following new network elements are included:

The mobile access gateway control function entity (mAGCF, Mobile Access Gate Control Function) 203, the difference between mAGCF203 and ICS MSC Server 103 mainly lies in that mAGCF mainly provides signaling conversion between CS and SIP, and no longer has the traditional CS domain MSC Server's access management and service control functions for users also cancel the interface with the traditional CS network. The intercommunication between mAGCF203 and the traditional CS network is through the media gateway control function entity (MGCF, Media Gate Control Function) of the IMS network accomplish.

Fig. 3 is a registration flow chart of the ICS enhanced service. As shown in Fig. 3, the terminal accesses the IMS network through the mAGCF and initiates registration on the IMS network. For the sake of simplicity, the process in Fig. 3 focuses on the location update process and IMS registration process of the CS domain, while ignoring the security authentication process.

The ICS Enhanced Registration process consists of the following steps:

In steps 301 to 302, the UE initiates a CS attachment process in the CS access network, and sends a CS location update request to the ICS MSC Server, and the message carries the UE's International Mobile Subscriber Identification Number (IMSI, International Mobile Subscriber Identification Number);

Step 303, the ICS MSC Server converts the received location update request message into a SIP registration message, obtains the user's home domain name according to the identity IMSI, and sends a registration message to the UE home domain IMS network entry network element I-CSCF. The private user identity (PVI, Private User Identity) derived by the ICS MSC Server based on the UE's IMSI.

In step 304, the I-CSCF receives the registration message and inquires about the registration status from the HSS, and the message carries the PVI of the UE. The HSS searches the current terminal registration status according to the UE's PVI. If it is a re-registration, it returns the S-CSCF address that the UE registered with. If it is the first registration, the HSS selects an S-CSCF address or returns a S-CSCF capability list;

Step 305, if the HSS returns the S-CSCF address information, the I-CSCF forwards the registration request message to the S-CSCF, and if the HSS returns the S-CSCF capability list, the I-CSCF selects an S-CSCF that meets the capability , and forward the registration request message to it;

Step 306, when the S-CSCF receives the registration request message, the authentication process may be triggered. For the sake of brevity, there is no more description here;

Step 307, the S-CSCF acquires user service subscription data from the HSS;

Step 308, the S-CSCF returns a registration success message to the mAGCF, and the message carries the UE's available public user identity (PUI, Public User Identity) list and default PUI;

Step 309, mAGCF saves S-CFCF address and user identification list and default PUI, and returns a location update success message to UE;

In the ICS enhanced technology, the MSC function is weakened, no longer has the service processing function, only responsible for protocol conversion and resource management, service triggering and control are centralized to the home IMS core network, and for the traditional CS network roaming mechanism, service control and The triggering is handled by the visited MSC, so according to the existing ICS enhancement technology, when the traditional user roams into the network described in the background art, the service cannot be triggered.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a user roaming method and an ICS enhanced network, which can realize the compatibility of the ICS enhanced network with communication services of other mobile network users.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

A method for user roaming, adding a marginal proxy function network element (BPF, Bounds Proxy Function) in an ICS enhanced network; the method includes:

After receiving the location update request message of the UE, the mAGCF sends a registration request message to the BPF when determining that the UE is another network user;

After the BPF receives the registration request message, the request message for obtaining user data sent to the HLR to which the user belongs is sent in a mobile application protocol (MAP, Mobile Application Part) message format;

After receiving the user data sent by the HLR, the BPF sends a registration response message to the mAGCF, and the mAGCF sends a location update response message to the UE.

Preferably, the determining that the UE is another network user specifically includes:

Configure the IMS centralized service ICS enhanced user identity list in the mAGCF;

After the mAGCF receives the UE's location update request message, it searches the ICS enhanced user identity list according to the identity of the UE in the location update request message to see if there is a match, and if not, determines that the UE is another Internet users.

Preferably, the determining that the UE is another network user specifically includes:

The mAGCF obtains the home domain information of the UE according to the IMSI of the UE in the location update message, and sends a registration request message to the I-CSCF where the UE is home; the I-CSCF determines whether the UE is other network users, and when the UE is another network user, notify the mAGCF.

Preferably, the determining that the UE is another network user specifically includes:

The mAGCF obtains the home domain information of the UE according to the IMSI of the UE in the location update message, and sends a registration request message to the inquiry call session control function entity I-CSCF to which the UE belongs;

The I-CSCF queries the HSS to which the UE belongs for the registration status of the UE, and notifies the mAGCF when determining that the UE is another network user according to the registration status of the UE returned by the HSS.

Preferably, the sending of the registration request message to the BPF is specifically:

The mAGCF sends a registration request message to the BPF according to the BPF address information configured in itself;

Alternatively, the mAGCF sends a redirection request message to the BPF to the I-CSCF, and sends a registration request message to the BPF according to the BPF address information in the redirection message returned by the I-CSCF ;

Or, the mAGCF sends the registration request message to the I-CSCF, and the I-CSCF forwards it to the BPF.

Preferably, the request message to be sent to the HLR to which the user belongs to acquire user data is sent in a MAP message format as follows:

The BPF obtains the PVI information of the UE in the registration request message, and obtains the IMSI of the UE according to the PVI information, and the BPF sends a location update request message to the HLR to which the UE belongs based on the MAP protocol, wherein the The location update request message carries the IMSI information and the BPF address information.

Preferably, the user data sent by the HLR received by the BPF is specifically:

The HLR sends an insert user data request message to the BPF based on the MAP protocol, and the insert user data request message carries the service data signed by the user;

The method also includes:

After the BPF receives the service data signed by the user, it triggers the third-party registration, and forwards the service data signed by the user to the local telephony application server (L-TAS, Local Telephony Application Server).

Preferably, the BPF generates a local initial filter control (iFC, Initial Filter Control) before triggering the third-party registration, wherein the iFC includes address information of the L-TAS and service trigger standard information.

Preferably, the method also includes:

After the BPF triggers the third party to register successfully, it sends a successful message of inserting user data to the HLR;

After the BPF receives the HLR location update response message, it sends a registration response message to the mAGCF;

The mAGCF saves the BPF address information and the UE's Mobile Station International Identity Number (MSISDN, Mobile Subscriber International ISDN) information after receiving the registration response message.

An ICS enhanced network comprising mAGCF, BPF and HLR; wherein,

The mAGCF is configured to send a registration request message to the BPF when determining that the UE is another network user after receiving the location update request message of the user equipment UE; and, after receiving the registration response message, send a registration request message to the UE Send a location update response message;

The BPF is configured to send, after receiving the registration request message, a request message for obtaining user data sent to the HLR to which the user belongs in a MAP message format; and, after receiving the user data sent by the HLR After that, send a registration response message to the mAGCF.

Preferably, an ICS enhanced user identity list is configured in the mAGCF; after the mAGCF receives the UE's location update request message, it lists the ICS enhanced user identity list according to the UE's identity in the location update request message. Check whether there is a matching item in the list, and if not, determine that the UE is another network user.

Preferably, the mAGCF obtains the UE's home domain information according to the UE's IMSI in the location update message, and sends a registration request message to the UE's home I-CSCF;

The I-CSCF further determines whether the UE is another network user, and notifies the mAGCF when the UE is another network user.

Preferably, the mAGCF further obtains the home domain information of the UE according to the IMSI of the UE in the location update message, and sends a registration request message to the Inquiry Call Session Control Function entity I-CSCF to which the UE belongs;

The I-CSCF queries the HSS to which the UE belongs for the registration status of the UE, and notifies the mAGCF when determining that the UE is another network user according to the registration status of the UE returned by the HSS.

Preferably, the mAGCF sends a registration request message to the BPF according to the BPF address information configured in itself;

Alternatively, the mAGCF sends a redirection request message to the BPF to the I-CSCF, and sends a registration request message to the BPF according to the BPF address information in the redirection message returned by the I-CSCF ;

Or, the mAGCF sends the registration request message to the I-CSCF, and the I-CSCF forwards it to the BPF.

Preferably, the BPF further obtains the PVI information of the UE in the registration request message, and obtains the IMSI of the UE according to the PVI information, and the BPF sends a location update request message to the HLR to which the UE belongs based on the MAP protocol , wherein the location update request message carries the IMSI information and the BPF address information.

Preferably, the HLR sends an insert user data request message to the BPF based on the MAP protocol, and the insert user data request message carries the service data subscribed by the user;

After receiving the service data signed by the user, the BPF triggers a third-party registration, and forwards the service data signed by the user to the L-TAS.

Preferably, the BPF generates a local initial filtering control iFC before triggering the third-party registration, wherein the iFC includes address information of the L-TAS and service trigger standard information.

Preferably, after the BPF triggers the third party to register successfully, it sends a message of inserting user data success to the HLR;

After the BPF receives the HLR location update response message, it sends a registration response message to the mAGCF;

The mAGCF saves the BPF address information and the MSISDN information of the UE after receiving the registration response message.

In the present invention, when a non-ICS-enhanced network UE roams into an ICS-enhanced network, because the ICS-enhanced network is not compatible with the existing mobile network, for a UE that roams to an ICS-enhanced network, since the UE cannot achieve ICS-enhanced Therefore, the UE cannot enjoy the communication service provided by the ICS-enhanced network. The invention sets BPF to realize the registration of the UE of the non-ICS enhanced network, so that the ICS enhanced network can carry out corresponding communication services according to the obtained user subscription data. The invention realizes the compatibility of the ICS-enhanced network with other network users, and realizes the services of the CS domain through the IMS.

Description of drawings

FIG. 1 is an architecture diagram of an IMS centralized control service;

Figure 2 is a schematic diagram of the ICS enhanced network architecture;

Fig. 3 is a registration flowchart of ICS enhanced service;

FIG. 4 is a schematic diagram of the ICS enhanced network architecture of the present invention;

FIG. 5 is a flow chart of a traditional user roaming to an ICS enhanced network registration in Embodiment 1 of the present invention;

FIG. 6 is a flow chart of a traditional user roaming to an ICS enhanced network registration in Embodiment 2 of the present invention;

FIG. 7 is a flow chart of a traditional user roaming to an ICS enhanced network registration in Embodiment 3 of the present invention.

Detailed ways

The basic idea of the present invention is to add a BPF in the ICS-enhanced network to realize the registration of UEs in the non-ICS-enhanced network, so that the ICS-enhanced network can carry out corresponding communication services according to the obtained user subscription data.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail by citing the following embodiments and referring to the accompanying drawings.

Figure 4 is a schematic diagram of the ICS enhanced network architecture of the present invention, as shown in Figure 4, compared with the existing ICS enhanced network, the ICS enhanced network of the present invention adds a new BPF, in addition, the present invention adds mAGCF, I in the ICS enhanced network - CSCF, HSS and L-TAS network elements have also been upgraded accordingly, and the corresponding functions of these network elements have been enhanced, specifically:

mAGCF is used to have the ability to perceive whether the current UE is another network user when the UE is attached, and select the appropriate BPF to send the registration request when it is found that the other network user roams to the ICS enhanced network;

After the mAGCF receives the redirection request message from the I-CSCF, the mAGCF sends a registration message according to the redirection address in the message;

The mAGCF also has the ability to obtain a Temporary Mobile Subscriber Identity (TMSI). When the mAGCF receives a location update request message carrying a temporary identity user identity, it obtains the UE's international mobile identity IMSI. The acquisition methods include the following methods:

a, mAGCF obtains from the UE;

b, or if the mAGCF can identify the TMSI, it acquires it from the mAGCF that allocates the TMSI according to the TMSI, or acquires it through the MSC.

I-CSCF is used to have the ability to perceive whether the current UE is another network user when receiving the registration request message. When it is found that the UE is roaming to the ICS enhanced network for other network users, the I-CSCF notifies mAGCF through the redirection request message Redirect to BPF or forward registration request message to BPF;

The HSS is used to return an indication that the user is another network user when the UE is judged to be another network user upon receiving the I-CSCF inquiry user registration status message;

The BPF has a protocol conversion capability. After receiving the registration request message, it saves the registration information, obtains the PVI information of the UE in the registration request message, and obtains the IMSI of the UE according to the PVI information of the UE. The BPF adopts the MAP protocol, Sending a location update request message to the HLR to which the UE belongs, where the location update request message carries the UE's IMSI information and BPF address information;

BPF is also used to store user data, and after receiving the request message for inserting user data, trigger third-party registration, and forward the obtained user subscription service data to the local telephone application server L-TAS;

Before BPF triggers the third-party registration, generate a local initial filtering control iFC, which contains the address of the L-TAS and the service triggering criteria;

The BPF also saves the registration address of the mAGCF; provides the routing number, and after receiving the CS domain roaming number provision request message of the UE, the BPF allocates the routing number or obtains the routing number through L-TAS;

BPF receives the call setup request, and routes the call to L-TAS according to L-iFC;

L-TAS provides the routing number. After receiving the BPF provision roaming number request message, the L-TAS assigns the routing number;

CS service control, after receiving the session invitation message, triggers service control according to the subscribed service.

In the following, in combination with the above network structure, how the present invention implements user roaming will be further described in detail.

Fig. 5 is a registration flow chart of a traditional user roaming to an ICS enhanced network in Embodiment 1 of the present invention. As shown in Fig. 5, this embodiment describes that a traditional CS user roams to an ICS enhanced network. After the mAGCF receives the UE's location update request message , it is judged as an other network user, select a BPF to send a registration request message, and before the BPF initiates a location update request message to the HLR to which the UE belongs, it converts the location update request message from the SIP format to the MAP format; thereby obtaining the user subscription data process from the HLR. Specifically include the following steps:

Steps 501 to 502, the traditional UE roams to the ICS enhanced network, and sends a location update request message through the CS wireless access network, where the location update request message carries the IMSI information of the UE's identity;

Step 503, after the mAGCF receives the UE location update request message, it judges whether the UE is another network user according to the user identity IMSI in the message, and judges whether its network element can adopt the following method:

The ICS enhanced user identity list pre-configured by mAGCF determines whether the current user belongs to the list, if not, it is considered to be other network users;

Or, mAGCF analyzes the IMSI number, usually the IMSI number is composed of a mobile country code (MCC, Mobile Country Code), a mobile network number (MNC, Mobile Network Code), and a mobile UE identification number (MSIN, Mobile Subscriber Identification Number), where MSIN is composed of HLR Number and user number SN. mAGCF can judge whether the current user belongs to ICS enhanced network through MCC+MNC or MCC+MNC+HLR Number in IMSI;

Or, mAGCF queries other network elements such as domain name server DNS;

If it is determined that the UE is another network user, select an adjacent BPF;

If the user identity in the location update message is TMSI, the mAGCF acquires the IMSI of the UE, and the acquisition methods include the following methods:

a. mAGCF obtains from the UE;

b. Or if the mAGCF recognizes the temporary identity user identity TMSI, obtain it from the mAGCF or MSC that allocates the TMSI;

Step 504, the mAGCF deduces the IMS network private user identity PVI from the IMIS, or directly uses the IMSI to send a SIP registration request message to the BPF, and the registration request message carries the IMIS or PVI information of the UE and the address information of the mAGCF;

Step 505: After receiving the registration request message, the BPF obtains the IMSI information in the registration request message, or re-deduces the user's IMSI information according to the PVI, and saves the binding relationship between the IMSI and the mAGCF address, and adopts the IMSI information to the HLR to which the UE belongs. The MAP protocol sends a location update request message, and the location update request message carries IMSI information and BPF address information;

Step 506, the HLR saves the corresponding relationship between the user IMSI and the BPF address information;

Step 507, the HLR sends an insert user data request message to the BPF, and the insert user data request message carries the user's subscription data information;

Step 508, the BPF saves the user data information, and after saving, returns the insert user data completion message to the HLR;

Step 509, the HLR returns a location update response message indicating that the location update is successful;

Step 510, BPF generates L-iFC, and generating L-iFC includes the following steps:

a. BPF selects a destination L-TAS and sets it as the AS address parameter in L-iFC

b. The BPF determines the L-iFC service trigger event and logic;

The BPF triggers the third-party registration, and forwards the obtained user subscription service data to the local telephone application server L-TAS;

It should be noted that the above step 510 may occur before step 508;

Step 511, the BPF returns a registration 200OK to notify the mAGCF that the registration is complete, and the 200OK message carries the user's MSISDN number;

In steps 512 to 513, the mAGCF returns a location update response message to the UE;

Fig. 6 is a flow chart of a traditional user roaming to the ICS enhanced network registration in Embodiment 2 of the present invention. The difference between this embodiment and Embodiment 1 is that after receiving the location update request message, the mAGCF deduces the user's home domain according to the user's IMSI , send a registration request message to the I-CSCF at the entrance of its home domain, and the I-CSCF determines that the current UE is another network user, and the I-CSCF notifies the mAGCF to forward the registration message to the BPF through a redirection message;

Step 601～step 602, same as step 501～step 502;

Step 603: After receiving the location update message, the mAGCF deduces the IMS network private user identity PVI according to the IMIS in the location update message, and sends an IMS registration request message to the user's home domain entry address I-CSCF;

Step 604, the I-CSCF receives the user registration request message, and judges whether the current UE is another network user, and the judgment methods include the following:

The ICS enhanced user identity list pre-configured by the I-CSCF determines whether the current user belongs to the list, and if not, considers it to be another network user;

Alternatively, the I-CSCF analyzes the PVI number to determine whether the current user belongs to the ICS enhanced network, and if not, considers it to be another network user;

Or, the I-CSCF queries the HSS to obtain whether the current UE is another network user;

If the I-CSCF finds that the current user is another network user, the I-CSCF sends a redirection request message to the mAGCF, which carries the destination BPF address information, and notifies the mAGCF to redirect the registration message to the destination BPF;

Step 605, according to the destination address in the redirection request message, the mAGCF redirects the registration message to the destination BPF;

Steps 606 to 613 are the same as steps 506 to 513, and will not be repeated here.

Fig. 7 is a flow chart of a traditional user roaming to the ICS enhanced network registration in Embodiment 3 of the present invention. The difference between this embodiment and the above Embodiment 2 is that after receiving the location update request message, the mAGCF deduces the user's affiliation according to the user's IMSI Domain, send a registration request message to the I-CSCF at the entrance of its home domain, and the I-CSCF finds that its user is another network user, and the I-CSCF forwards the registration request message to the BPF;

Step 701～step 703 is the same as step 601～step 603;

Step 704, the I-CSCF perceives that the user is another network user, selects a BPF, and forwards the registration request message to the destination BPF;

Step 705-step 713 are the same as step 606-step 614, and will not be repeated here.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (18)

1. A user roaming method is characterized in that, in the IMS centralized service ICS enhanced network, the marginal agent function network element BPF is added; the method comprises: After receiving the location update request message of the user equipment UE, the mobile access gateway control function entity mAGCF sends a registration request message to the BPF when determining that the UE is another network user; After the BPF receives the registration request message, the request message for obtaining user data sent to the home location register HLR to which the user belongs is sent in a mobile application protocol MAP message format; After receiving the user data sent by the HLR, the BPF sends a registration response message to the mAGCF, and the mAGCF sends a location update response message to the UE. 2. The method according to claim 1, wherein the determining that the UE is another network user is specifically: Configuring an ICS enhanced user identity list in the mAGCF; After the mAGCF receives the UE's location update request message, it searches the ICS enhanced user identity list according to the identity of the UE in the location update request message to see if there is a match, and if not, determines that the UE is another Internet users. 3. The method according to claim 1, wherein the determining that the UE is another network user is specifically: The mAGCF obtains the home domain information of the UE according to the International Mobile Subscriber Identity IMSI of the UE in the location update message, and sends a registration request message to the inquiry call session control function entity I-CSCF to which the UE belongs; The I-CSCF determines whether the UE is another network user, and notifies the mAGCF when the UE is another network user. 4. The method according to claim 1, wherein the determining that the UE is another network user is specifically: The mAGCF obtains the home domain information of the UE according to the International Mobile Subscriber Identity IMSI of the UE in the location update message, and sends a registration request message to the inquiry call session control function entity I-CSCF to which the UE belongs; The I-CSCF queries the HSS to which the UE belongs for the registration status of the UE, and notifies the mAGCF when determining that the UE is another network user according to the registration status of the UE returned by the HSS. 5. The method according to claim 1, wherein the sending the registration request message to the BPF is specifically: The mAGCF sends a registration request message to the BPF according to the BPF address information configured in itself; Alternatively, the mAGCF sends a redirection request message to the BPF to the I-CSCF where the UE is home, and sends a request message to the BPF according to the BPF address information in the redirection message returned by the I-CSCF registration request message; Or, the mAGCF sends the registration request message to the home I-CSCF of the UE, and the I-CSCF forwards it to the BPF. 6. The method according to claim 1, wherein the request message for obtaining user data that will be sent to the home location register HLR to which the user belongs is sent in a mobile application protocol MAP message format as follows: The BPF obtains the private user identity PVI information of the UE in the registration request message, and obtains the IMSI of the UE according to the PVI information, and the BPF sends a location update request message to the HLR to which the UE belongs based on the MAP protocol, Wherein, the location update request message carries the IMSI information and the BPF address information. 7. The method according to claim 1, wherein the user data sent by the HLR received by the BPF is specifically: The HLR sends an insert user data request message to the BPF based on the MAP protocol, and the insert user data request message carries the service data signed by the user; The method also includes: After receiving the service data signed by the user, the BPF triggers a third-party registration, and forwards the service data signed by the user to the local telephone application server L-TAS. 8. The method according to claim 7, wherein the BPF generates a local initial filtering control iFC before triggering the third-party registration, wherein the iFC includes address information of the L-TAS and service trigger standard information . 9. The method according to claim 7, further comprising: After the BPF triggers the third party to register successfully, it sends a successful message of inserting user data to the HLR; After the BPF receives the HLR location update response message, it sends a registration response message to the mAGCF; The mAGCF saves the BPF address information and the UE's International Mobile Subscriber Number (MSISDN) information after receiving the registration response message. 10. An IMS centralized service ICS enhanced network, characterized in that, the ICS enhanced network includes a mobile access gateway control function entity mAGCF, a marginal proxy function network element BPF and a home location register HLR; wherein, The mAGCF is configured to send a registration request message to the BPF when determining that the UE is another network user after receiving the location update request message of the user equipment UE; and, after receiving the registration response message, send a registration request message to the The UE sends a location update response message; The BPF is configured to send, after receiving the registration request message, a request message for obtaining user data sent to the HLR to which the user belongs in a MAP message format; and, after receiving the user data sent by the HLR After that, send a registration response message to the mAGCF. 11. The ICS enhanced network according to claim 10, wherein an ICS enhanced user identity list is configured in the mAGCF; after the mAGCF receives the UE's location update request message, it Check whether there is a matching item in the ICS enhanced user identity list for the identity of the UE, and if not, determine that the UE is another network user. 12. The ICS-enhanced network according to claim 10, wherein the mAGCF obtains the home domain information of the UE according to the IMSI of the UE in the location update message, and makes a query call to the home of the UE The session control function entity I-CSCF sends a registration request message; The I-CSCF further determines whether the UE is another network user, and notifies the mAGCF when the UE is another network user. 13. The ICS-enhanced network according to claim 10, wherein the mAGCF further obtains the home domain information of the UE according to the IMSI of the UE in the location update message, and queries the home of the UE The call session control function entity I-CSCF sends a registration request message; The I-CSCF queries the HSS to which the UE belongs for the registration status of the UE, and notifies the mAGCF when determining that the UE is another network user according to the registration status of the UE returned by the HSS. 14. The ICS enhanced network according to claim 10, wherein the mAGCF sends a registration request message to the BPF according to the BPF address information configured in itself; Alternatively, the mAGCF sends a redirection request message to the BPF to the I-CSCF where the UE is home, and sends a request message to the BPF according to the BPF address information in the redirection message returned by the I-CSCF registration request message; Or, the mAGCF sends the registration request message to the home I-CSCF of the UE, and the I-CSCF forwards it to the BPF. 15. The ICS-enhanced network according to claim 10, wherein the BPF further obtains the PVI information of the UE in the registration request message, and obtains the IMSI of the UE according to the PVI information, and the BPF is based on The MAP protocol sends a location update request message to the HLR to which the UE belongs, where the location update request message carries the IMSI information and the BPF address information. 16. The ICS enhanced network according to claim 10, wherein the HLR sends an insert user data request message to the BPF based on the MAP protocol, and the insert user data request message carries the service data subscribed by the user ; After receiving the service data signed by the user, the BPF triggers a third-party registration, and forwards the service data signed by the user to the local telephone application server L-TAS. 17. The ICS enhanced network according to claim 16, wherein the BPF generates a local initial filtering control iFC before triggering the third-party registration, wherein the iFC includes address information of the L-TAS, service trigger standard information. 18. The ICS enhanced network according to claim 16, characterized in that, after the BPF triggers a third party to register successfully, it sends a successful message of inserting user data to the HLR; After the BPF receives the HLR location update response message, it sends a registration response message to the mAGCF; The mAGCF saves the BPF address information and the UE's International Mobile Subscriber Number (MSISDN) information after receiving the registration response message.