WO2007012269A1

WO2007012269A1 - A method of user registration and call continuance in ip multimedia terminal and system

Info

Publication number: WO2007012269A1
Application number: PCT/CN2006/001833
Authority: WO
Inventors: Hui Li
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2005-07-29
Filing date: 2006-07-25
Publication date: 2007-02-01
Also published as: CN1882172A; CN100450292C

Abstract

A method of user registration in IP multimedia subsystem resolves the problem that the present art only provides the method for initiating registration by regarding the SIP URI identifier as the essential identifier, the user can not select, and the implemention is complex for satisfying the conventional user terminal and user custom. The invention includes: the user initiates the registration by regarding the E.164 identifier as the essential identifier; IMS terminal converts the E.164 identifier to the registration identifier accorded with SIP protocol, and adds the registration identifier to a registration request message; the network device in the IMS network implements the authentication and registration according to the said registration request message.

Description

Method for using Lu registration and session connection in IP multimedia terminal and system

The present invention relates to a 3G wireless network, and more particularly to a method for user registration and session connection in an IP multimedia terminal and system. Background technique

The IP Multimedia Subsystem (IMS) is a subsystem that is superimposed on the packet network by the 3rd Generation Mobile Communications Standardization Partnership Project (3GPP). The IMS uses a packet domain as a bearer channel for its control signaling and media transmission, and introduces a Session Initiation Protocol (SIP) as a service control protocol. Provides rich multimedia services by separating service control from bearer control.

In the IMS application, in order to complete the registration function of the user (UE) and the service of the calling party and the called party, the 3GPP defines two public identities:

1. Public User Identity (IMPU): The user communicates using the IMPU. Each IMS user has one or more IMPUs. The IMPU has a Session Initiation Protocol Universal Resource Identity (SIP URI) format or an E.164 format, both representations. For example: SIP URI is sip:tom@example.com; E.164 is 13912345678. The IMPU is initially stored in the UE IMS Subscriber Identity Module (ISIM) and the HSS.

2. Public Service Identity (PSI): The PSI is used to correspond to a specific service in an application server. Public service IDs are in SIP URI or E.164 format, for example: sip:conference@examplenetwork.com ₀

The 3GPP specifies that the SIP URI is the basic identifier of the IMS, that is, the IMS user or the service must have the SIP URI identifier. According to this, the IMS uses the DNS URI for the SIP URI and obtains the network address for routing.

With the development of IMS and the need for mobile and fixed convergence, IMS has become the best solution for mobile and fixed convergence. Currently, in order to enable IMS to interoperate with the Public Telephone Service Network/Public Land Mobile Network (PSTN/PLMN), 3GPP introduces the E.164 identity by means of implicit registration. But In 3GPP, the basic identifier is the mandatory identifier, so the user must have the SIP URI identifier, but there is no E.164 identifier.

Based on the above regulations, the current registration process for IMS users is shown in Figure 1. The steps visible in the figure are as follows:

- the user initiates a registration request using the SIP URI identifier in the IMPU, and sends the registration request to the P-CSCF;

- the P-CSCF performs DNS protocol resolution on the home network address in the registration request, obtains an I-CSCF address in the user's home network, and forwards the registration request to the I-CSCF;

- the I-CSCF queries the HSS for the user registration status, obtains the address of the S-CSCF serving the user according to the information returned by the HSS, and sends the registration message to the S-CSCF;

- The S-CSCF queries the HSS and obtains the user's authentication information, and then initiates an authentication challenge (401 Challenge) to the user;

- The user calculates the authentication response and re-initiates the registration process. If the S-CSCF passes the authentication, it returns a successful confirmation and completes the registration process.

At present, the session connection of the IMS user is divided into the connection in the home network of the calling user. The process is shown in FIG. 2, and the connection in the home network of the called user is shown in FIG. 3, which can be seen from the above two figures. The following steps are as follows:

- the user initiates an implicit session request using the SIP URI identifier in the IMPU, and sends the session request to the P-CSCF;

- the P-CSCF forwards the session request to the S-CSCF according to the path saved by the user when registering;

- Due to the implicit session mode, the S-CSCF performs ENUM resolution on the called E.164 identifier. If the parsing fails, the called party is considered to be a PS N/PMN user, and the session request is forwarded to the BGCF.

The BGCF queries the internal or external routing data, obtains the MGCF address, and forwards the request to the MGCF.

The MGCF forwards the session request to the PSTN/PMN to which the called user belongs.

If the resolution is successful, the called party is an IMS user, obtains the called SIP URI according to the address parsed by ENUM, performs DNS resolution on the SIP URI, obtains the I-CSCF address to which the called user belongs, and then forwards the session. Request to the I-CSCF. -I-CSCF to the HSS to query the called user location information, and obtain the address of the S-CSCF that provides the service to the called user. Thereafter, the session request is forwarded to the S-CSCF. The connection is completed by the S-CSCF.

At present, the traditional fixed terminal adopts the E.164 numbering method, that is, the number is used as the numbering method of the telephone number. However, in the 3GPP IMS standard, the SIP URI identifier is used as the basic identifier of the user or service. Although the E.164 identification scheme is provided (implicit mode), the E.164 identifier is an optional identifier that is mainly used in the case of IMS and PSTN/PLMN interworking. In the IMS standard, when the IMS network supports the fixed network user connection with the SIP URI as the basic identifier, there may be number conversion and interworking problems, and it is more complicated to meet the traditional user terminal and user habits. Summary of the invention

The present invention provides a method for IMS user registration, which is used to solve the problem that the prior art only provides the SIP URI identifier as the basic identifier to initiate registration, the user has no choice, and the implementation is complicated to meet the traditional user terminal and user habits. problem.

The present invention also provides a method for IMS session connection, which solves the problem that the prior art may have a code conversion and interworking problem, and requires ENUM parsing and DNS parsing in the connection process, so that the connection is complicated.

In order to support the method, the present invention provides an IMS terminal.

The registration method of the present invention includes the steps of:

A. The user initiates a registration request with the E.164 identifier as the basic identifier;

B. The IMS terminal converts the E.164 identifier into a registration identifier conforming to the SIP protocol, and adds the registration identifier to the registration request message;

C. The network device in the IMS network completes authentication and registration according to the registration request message.

The step C includes the following steps:

Cl, the proxy call session control function (P-CSCF) acquires an address of the query call session control function entity (I-CSCF) in the home network of the IMS terminal, and sends the registration request message to the I-CSCF; C2, the I-CSCF obtains an address of a serving call session control function entity (S-CSCF) to which the IMS terminal belongs, and sends the registration request message to the S-CSCF;

C3. The S-CSCF obtains authentication information corresponding to the user, and completes authentication and registration.

The registration identifier is a Session Initiation Protocol Universal Resource Identity (SIP URI).

The domain name of E.164. Alternatively, the E.164 identifier is converted into a SIP URI format identifier according to the tel format identifier converted to the SIP URI format identifier, where the translated SIP URI identifier is named as the user's home network domain name.

In the step C1, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs a domain name resolution protocol (DNS) on the address to obtain an I-CSCF address in the home network of the IMS terminal. . In step C2, the I-CSCF restores the E.164, and converts the E.164 into a TEL URI format for obtaining an address of the S-CSCF to which the IMS terminal belongs from the home subscription subscriber server (HSS). . In the step C3, the S-CSCF restores the E.164, and converts the E.164 into the TEL U1 format for obtaining the user's authentication information from the HSS.

Establishing a correspondence between the address information and the authentication information set in the home subscriber network (HSS) and the SIP URI after the E.164 conversion, the I-CSCF in the step C2 directly queries the registration identifier. The address of the S-CSCF to which the IMS terminal belongs. In the step C3, the S-CSCF directly queries the HSS for the user's rights information with the registration identifier.

The registration identifier is a TEL URL

In the step C1, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs DNS protocol resolution on the address to obtain the I-CSCF address in the home network of the IMS terminal. In the step C2, the I-CSCF obtains the address of the S-CSCF to which the IMS terminal belongs from the HSS by using the registration identifier. In the step C3, the S-CSCF directly obtains the user's authentication information from the HSS by using the registration identifier.

The method for session connection of the present invention comprises the following steps:

The IMS calling terminal initiates a session request with the called E.164 identifier; in the calling terminal home network, converts the E.164 identifier into a universal resource format identifier (URI), and obtains the URI by the URI The called terminal belongs to the next hop address in the network; sends the session request to the next hop address, and completes the connection in the called terminal's home network.

Converting the E.164 identifier into a URI, and obtaining the next hop address in the home network of the called terminal by using the URI is an E.164 Identity Translation Protocol (ENUM) server set with the E.164 converted SIP URI Querying the SIP URI corresponding to the called party; performing DNS resolution on the SIP URI to obtain the next hop address.

Converting the E.164 identifier into a URI, and obtaining the next hop address in the home network of the called terminal by using the URI is that the S-CSCF to which the calling terminal belongs converts the called E.164 identifier into a TEL URI, and The TEL UI is queried in the database for the corresponding next hop address. The database is an internal routing database, or an external routing database.

If the obtained next hop address is an I-CSCF address, the connection in the home network of the called terminal is completed, including the following steps:

- the I-CSCF queries the HSS for location information of the called terminal;

- carrying the message of the HSS response carrying the S-CSCF address to which the called terminal belongs;

- The I-CSCF forwards the session request to the S-CSCF, and the S-CSCF completes the connection. If the acquired next hop address is the address of the edge gateway control function entity (BGCF), completing the connection in the called terminal home network includes the following steps:

- the BGCF forwards the session request to a Media Gateway Control Function Entity (MGCF);

- The session request is sent by the MGCF to the Public Telephone Service Network (PSTN) or the Public Land Mobile Network (PLMN) and the connection is completed.

An IMS terminal of the present invention includes: a terminal body;

The conversion module is disposed inside the terminal body and configured to convert the E.164 identifier into a registration identifier conforming to the SIP protocol.

The beneficial effects of the present invention are as follows:

The invention uses the E.164 identifier as the basic identifier of the IP multimedia subsystem. According to the provisions of the 3GPP protocol, when the user registers, the registration process is initiated with the basic identifier. The present invention converts E.164 into a registration identifier in a TEL URI format or a SIP URI format, and adds the registration identifier to the registration request The registration is initiated in the message. In the registration process, it is necessary to restore the E.164 place to reversely convert the registration mark, realize the rights of the woman and complete the registration. In this way, the user can not only initiate registration by using the SIP of the prior art as the basic identifier, but also initiate registration by using the E.164 as the basic identifier, which increases the user's selectivity, thereby better supporting the traditional user terminal and the user's habit.

The invention uses the E.164 identifier as the basic identifier of the IP multimedia subsystem. When the calling user initiates a call, the called E.164 identifier is used to query the address of the corresponding I-CSCF to which the called user belongs, or the E.164 identifier is used to query the address of the BGCF to which the called user belongs, and then according to the address of the BGCF to which the called user belongs. The queried address connects the session to the corresponding network element entity, and then completes the connection in the called side network to implement session connection. Through the implementation of the present invention, the ENUM parsing can be avoided in the connection process, and the connection process is completed; the next hop address is obtained through the query mode, and the number conversion is avoided in the connection process, thereby better solving the number conversion and interworking problems. DRAWINGS

1 is a signaling flow chart of a prior art registration method;

2 is a flow chart of session connection signaling in a prior art calling home network;

3 is a flow chart of the connection signaling in the prior art called home network;

4 is a signaling flowchart of a registration method of the present invention;

Figure 5 is a flow chart showing the steps of the registration method of the present invention;

6 is a signaling flowchart of a method for connecting a tongue of the present invention;

7 is a flow chart of steps of a session connection method according to the present invention;

FIG. 8 is a flow chart of steps of another session connection method according to the present invention. detailed description

In order to make the E.164 identifier as the basic identifier of the IP Multimedia Subsystem (IMS), thereby increasing the user's selectivity, and better supporting the traditional user terminal and user habits, the present invention provides an IP multimedia terminal, including:

a terminal body for implementing functions inherent to the IMS terminal; The conversion module is disposed inside the terminal body and configured to convert the E.164 identifier into a registration identifier conforming to the SIP protocol.

Based on the above IMS terminal, the present invention provides a method for user registration in an IP multimedia subsystem. Referring to Figure 4 and Figure 5, the following steps are included:

S1. The user initiates a registration request with the E.164 identifier as the basic identifier.

52. The IMS terminal converts the E.164 identifier into an identifier of a SIP URI format, and adds the identifier of the SIP URI format to the registration request message.

53. The Proxy Call Session Control Function (P-CSCF) entity obtains an address of an Inquiring Call Session Control Function Entity (I-CSCF) in the home network of the IMS terminal.

54. Send a registration request message to the I-CSCF.

55. The I-CSCF obtains an address of a serving call session control function entity (S-CSCF) to which the IMS terminal belongs.

56. Send a registration request message to the S-CSCF.

57. The S-CSCF obtains authentication information corresponding to the user, and completes authentication and registration.

The following describes the method of IMS user registration in three examples.

Example 1: The database in the Home Subscriber Server (HSS) is not modified, and the E.164 standard is converted into the identifier of the Session Initiation Protocol Common Resource (SIP U I ) format to complete the authentication and registration. The specific processing steps of this example are as follows:

5101. The user initiates a registration request by using the E.164 identifier as the basic identifier.

Since the existing protocol specifies that the SIP URI is the basic identifier of the IMS, and the E.164 is identified as the subordinate identifier, in order to implement the present invention, the E.164 identifier is defined as the basic identifier.

In this way, the user can initiate a registration request to the network side by using the E.164 identifier as the basic identifier.

5102. The IMS terminal converts the E.164 identifier into an identifier of a SIP URI format, and adds the identifier of the SIP URI format to the registration request message.

The IMS terminal uses the conversion module to add a domain name for identifying E.164 after the E.164 identification.

For example: The E.164 number is +46-8-9761234. The identifier of the converted SIP UI format is sip: 4689761234@el64.3gppnetwork.org. The domain name el64. 3gppnetwork.org is used to indicate that this is an E.164 number.

Or the IMS terminal uses the conversion module to convert the identifier of the tel format into the identifier of the SIP URI format, and converts the E.164 identifier into an identifier of the SIP URI format, where the domain name of the converted SIP URI identifier is The home network domain name of the user.

For example: The E.164 number is +46-8-9761234. The converted SIP URI format is identified as sip: +46-8-9761234@example.com , user=phone.

The SIP URI format identifier is then populated into the registration message header field to initiate a registration request.

5103. The Proxy Call Session Control Function (P-CSCF) entity obtains an address of an Incoming Call Session Control Function Entity (I-CSCF) in the home network of the IMS terminal.

After receiving the registration request message, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs DNS resolution on the home network address to obtain the home network of the IMS terminal. The address of the I-CSCF.

5104. Send a registration request message to the I-CSCF.

5105. The I-CSCF acquires an address of a serving call session control function entity (S-CSCF) to which the IMS terminal belongs.

After receiving the registration request message, the I-CSCF obtains the identifier of the SIP URI format, and restores the identifier of the SIP URI format to an E.164 identifier (the restoration method is opposite to the forwarding method); The E.164 is converted to the TEL UI format identifier (for the conversion method, see Protocol: RFC2806).

The address of the S-CSCF to which the IMS terminal belongs can be queried in the Home Subscriber Server (HSS) using the obtained TEL U I format identifier.

5106. Send a registration request message to the S-CSCF.

5107. The S-CSCF obtains authentication information corresponding to the user, and completes authentication and registration.

After receiving the registration request message, the S-CSCF obtains the identifier of the SIP URI format, and restores the identifier of the SIP URI format to an E.164 identifier (the restoration method is opposite to the forwarding method); The E.104 is converted to the identifier of the TEL URI format (for the conversion method, see Protocol: RFC2806).

The user corresponding to the TEL URI identifier can be queried in the HSS by using the obtained TEL URI identifier. The authentication information, that is, the user right information corresponding to the E.164 identifier of the user is queried. After that, the user registration is completed according to the flow of the prior art and the query method of this example.

Example 2: Modify the database in the HSS and convert the E.164 identifier into the identifier of the SIP URI format to complete the authentication and registration. The specific processing steps of this example are as follows:

S201. The user initiates a registration request by using the E.164 identifier as the basic identifier.

Since the existing protocol specifies that the SIP URI is the basic identifier of the IMS, E.164 is identified as the subordinate identifier. To implement the present invention, the E.164 identifier is also defined as the basic identifier.

5202. The IMS terminal converts the E.164 identifier into an identifier of a SIP URI format, and adds the identifier of the SIP URI format to the registration request message.

For example: The R164 number is +46-8-9761234. The converted SIP URI format is identified as sip: 4689761234@el64.3gppnetwork.org. The domain name el64. 3gppnetwork.org is used to indicate that this is an E.164 number.

For example: The E.164 number is +46-8-9761234. The converted SIP URI format is identified as sip: +46-8-9761234@example.com, user=phone ₀

S203: The P-CSCF obtains an address of the I-CSCF in the home network of the IMS terminal.

5204. Send a registration request message to the I-CSCF.

S205. The I-CSCF obtains an address of an S-CSCF to which the IMS terminal belongs. Since the prior art only supports querying information to the HSS by using the original SIP URI identifier and the TELURI identifier of the user, this example first sets the TELURI identifier query supported by the prior art in the address information database of the HSS and the subscription database, indirectly by E. 164 converted SIP URI query related information.

After receiving the registration request message, the I-CSCF obtains the identifier of the SIP URI format, and directly queries the HSS for the IMS terminal's belonging S by using the identifier of the SIP URI format. - The address of the CSCF.

5206. Send a registration request message to the S-CSCF.

S207. The S-CSCF obtains the authentication information corresponding to the user, and completes the authentication and registration.

After receiving the registration request message, the S-CSCF obtains the identifier of the SIP URI format, and directly queries the HSS for the authentication information of the corresponding user by using the identifier of the SIP URI format. That is, the authentication information of the user corresponding to the E.164 identifier of the user is queried.

Thereafter, the user registration is completed in accordance with the flow of the prior art.

Example 3: Convert the E.164 identifier into an identifier in the TEL URI format to complete authentication and registration. The specific processing steps of this example are as follows:

S301. The user initiates a registration request by using the E.164 identifier as the basic identifier.

5302. The IMS terminal converts the E.164 identifier into an identifier of a TEL URI format, and adds the identifier of the SIP URI format to the registration request message. (For the conversion method, see the agreement: RFC2806)

5303. The P-CSCF obtains an address of the I-CSCF in the home network of the IMS terminal.

After receiving the registration request message, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs DNS resolution on the home network address to obtain the home network of the IMS terminal. The address of the I-CSCF. 5304. Send a registration request message to the I-CSCF.

S305. The I-CSCF obtains an address of an S-CSCF to which the IMS terminal belongs.

Since the prior art supports the information in the TEL URI format to query the information of the HSS, the I-CSCF directly obtains the address of the S-CSCF to which the IMS terminal belongs from the HSS by using the identifier in the TEL URI format.

5306. Send a registration request message to the S-CSCF.

S307. The S-CSCF obtains the authentication information corresponding to the user, and completes the authentication and registration.

The S-CSCF obtains the authentication information of the corresponding user from the HSS by using the identifier of the TEL URI format, that is, the S-CSCF obtains the authentication information corresponding to the E.164 identifier. User authentication information.

In order to better solve the number conversion and intercommunication, and simplify the session connection process. The present invention provides a method of session connection in an IMS system.

The following describes the method of IMS user session connection in two examples.

Example 4: Setting the E.164-converted SIP URI format identifier in the ENUM server to obtain the identifier of the corresponding SIP URI format when the session is initiated by E.164, and further obtain the next hop address through DNS decryption. , to complete the connection. Referring to Figure 6 and Figure 7, the specific processing steps of this example are as follows:

S401. The IMS calling terminal initiates a session request with the called E.164.

After receiving the session request message, the P-CSCF forwards the session request message to the S-CSCF in the calling home network according to the path saved by the user when registering.

S403. The S-CSCF in the home network of the calling terminal corresponds to the identifier of the SIP URI format. The service provider first sets the E.164 identity converted SIP of each IMS user in the ENUM server.

The identifier of the URI format.

For example: The E.164 number is +46-8-9761234. The converted SIP UI format is identified as sip: 4689761234@el64.3gppnetwork.org. The domain name el64. 3gppnetwork.org is used to indicate that this is an E.164 number. When the network side receives the session request, the E.164 identifier of the called user is used to query the ENUM server for the identifier of the corresponding SIP URI format.

If the identifier of the corresponding SIP OKI format is queried, the called user is considered to be an IMS user, and the process proceeds to step S404;

Otherwise, the called party is considered to be a PSTN or PLMN user, and proceeds to step S406.

5404. Perform DNS resolution on the obtained identifier of the SIP URI format, and obtain an I-CSCF address in the home network of the called terminal.

5405. Perform the connection in the called IMS home network.

- the I-CSCF in the called home network converts the E.164 identifier in the session request message into an identifier in the TEL URI format (see the protocol: KFC2806 for the conversion method), and queries the HSS with the identifier in the TEL URI format. Location information of the called terminal;

- The I-CSCF forwards the session request to the S-CSCF, and the S-CSCF completes the connection.

5406. The connection is completed in the called PSTN or PLMN network.

After receiving the session request message, the BGCF forwards the session request message to a media gateway control function entity (MGCF);

- The session request message is sent by the MGCF to the PSTN or PLMN and completed in accordance with the prior art.

Example 5: Convert the E.164 identifier into an identifier in the TEL URI format, which is used to query the next hop address and complete the connection. Referring to Figure 6 and Figure 8, the specific processing steps of this example are as follows:

The S50K IMS calling terminal initiates a session request with the called E.164 identity.

5503. The S-CSCF in the calling home network converts the E.164 identifier in the tongue request message into an identifier in the TEL URI format.

S504: Query the corresponding next hop address in the database by using the TEL U I.

The database is an internal routing database, or an external routing database. If the next hop address in the called home network obtained by the query is an I-CSCF address, that is, the called terminal is an IMS terminal, then the process proceeds to step S505;

If the acquired next hop address in the called home network is the address of the edge gateway control function entity (BGCF), that is, the called terminal is a public telephone service network (PSTN) terminal or a public land mobile network (PLMN) terminal, then Proceed to step S506.

5505. Perform the connection in the called IMS home network.

- the I-CSCF in the called home network converts the E.164 identifier in the session request message into an identifier in the TEL URI format, and queries the HSS for the location information of the called terminal in the TEL URI format identifier;

5506. The connection is completed in the called PSTN or PLMN network.

- The session request message is sent by the MGCF to the PSTN or PLMN and completed in accordance with the prior art. The spirit and scope of the invention. Therefore, it is intended that the present invention cover the modifications and variations of the invention as claimed.

Claims

Rights request

A method for user registration in an IP multimedia subsystem, comprising the steps of:

2. The method according to claim 1, wherein the step C comprises the following steps: Cl, a proxy call session control function (P-CSCF), acquiring an inquiry call session control function entity in the home network of the IMS terminal An address of (I-CSCF), and sending the registration request message to the I-CSCF;

C2, the I-CSCF obtains an address of a serving call session control function entity (S-CSCF) to which the IMS terminal belongs, and sends the registration request message to the S-CSCF;

3. The method according to claim 2, wherein the registration identifier is a session initiation protocol universal resource identifier (SIP URI).

The method according to claim 3, wherein the converting the E.164 identifier into a SIP URI is to add a domain name for identifying E.164 after the E.164 identifier;

Alternatively, the E.164 identifier is converted into a SIP URI format identifier according to the tel format identifier converted to the SIP URI format identifier, where the translated SIP URI identifier domain name is the user's home network domain name.

The method according to claim 4, wherein in the step C1, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs a domain name resolution protocol (DNS) on the address. Obtaining an I-CSCF address in the home network of the IMS terminal.

The method according to any one of claims 3 to 5, wherein in step C2, the I-CSCF restores the E.164, and converts the E.164 into a TEL URI format for The address of the S-CSCF to which the IMS terminal belongs is obtained in the Home Subscriber Server (HSS).

7. The method according to claim 6, wherein in step C3, the S-CSCF restores the E.164, and converts the E.164 into a TEL URI format for acquiring a user from the HSS. Authentication information.

The method according to any one of claims 3 to 5, characterized in that between the address information and the authentication information set in the home subscriber network (HSS) and the SIP URI after the conversion of the E.164 are established. In the corresponding relationship, the I-CSCF in the step C2 directly queries the address of the S-CSCF to which the IMS terminal belongs by using the registration identifier.

The method of claim 8, wherein the S-CSCF in the step C3 directly queries the HSS for the authentication information of the user by using the registration identifier.

10. The method of claim 2, wherein the registration identifier is a TEL URL

The method according to claim 10, wherein in the step C1, the P-CSCF obtains the home network address of the IMS terminal from the header field of the registration request message, and performs DNS protocol analysis on the address to obtain The IMS terminal belongs to an I-CSCF address in the network.

The method according to claim 10 or 11, wherein in the step C2, the I-CSCF obtains the address of the S-CSCF to which the IMS terminal belongs from the HSS by using the registration identifier.

The method according to claim 12, wherein in the step C3, the S-CSCF directly obtains the authentication information of the user from the HSS by using the registration identifier.

14. A method for session connection in an IP multimedia subsystem, comprising the steps of:

The IMS calling terminal initiates a session request with the called E.164 identifier;

Translating the E.164 identifier into a common resource format identifier (URI) in the calling terminal home network, and acquiring the next hop address in the called terminal home network by using the URI;

The session request is sent to the next hop address, and the connection in the home network of the called terminal is completed.

The method according to claim 14, wherein the converting the E.164 identifier into a UI, and acquiring the next hop address in the home network of the called terminal by using the UI is configured to have an E.164 conversion The SIP URI's E.164 Identity Translation Protocol (ENUM) is used to query the called SIP UR [; Performing DNS resolution on the SIP URI to obtain the next hop address.

The method according to claim 14, wherein the E.164 identifier is converted into a URI, and the next hop address in the home network of the called terminal is obtained by the URI as the S-home of the calling terminal. The CSCF converts the called E.164 identifier into a TEL URL and queries the database for the corresponding next hop address with the TEL URI.

17. The method of claim 16, wherein the database is an internal routing database or an external routing database.

The method according to any one of claims 14 to 17, wherein if the acquired next hop address is an I-CSCF address, the connection in the home network of the called terminal is completed, and the following steps are included:

- the I-CSCF queries the HSS for location information of the called terminal;

The method according to any one of claims 14 to 17, wherein if the acquired next hop address is an address of an edge gateway control function entity (BGCF), the connection in the called terminal home network is completed. , including the following steps:

- The session request is sent by the MGCF to the Public Telephone Service Network (JPSTN) or the Public Land Mobile Network (PLMN) and the connection is completed.

20. An IMS terminal, comprising: a terminal body,

The IMS terminal further includes: