CN1964394B - A system and method for realizing number portability service - Google Patents

Abstract

The invention discloses a system for realizing the number portability service, a number portability application server, a number portability service trigger logic device and a method for realizing the number portability service, so as to solve the problem of no number portability mechanism in the current IMS system. The system includes: the home subscriber server HSS, and the number portability database NPDB, which stores the corresponding relationship between the address assigned by the called user's first subscription network and the address assigned by the user's current subscription network; the number portability NPDB The service trigger logic device, according to the built-in logic of the device, forwards the session request to the number portability application server NP-AS through the HSS; The address assigned by the current contracted network, and directly complete the session routing according to the address, or redirect the address to the first contracted network of the called user to complete the session routing.

Description

A system and method for realizing number portability service

technical field

The invention relates to the communication field, in particular to a system and method for realizing number portability services.

Background technique

The number portability service Number Portability is also called mobile phone transfer without changing the number service. That is, after the user changes the telecom operator, the original user number is still retained, and the original number is used to communicate with others.

Because the NP business brings great convenience for users to change operators. At present, the telecommunications management bureaus of many countries and regions require all network operators to provide "number portability" services for fair competition, so as to avoid the inconvenience caused by users having to change numbers after changing operators, and give up the replacement to provide better quality, more economical operator.

The IMS network is the core network of the next generation communication network. As the core session control layer of fixed and mobile networks, it has become the focus of discussion in the industry. The IMS protocol stipulates that each IMS user has a private user ID and at least one public user ID. The private identifier is specified by the operator of the user's home network. This identifier is used to uniquely identify a subscriber in the home network for user registration, authentication, management, and billing. Since the private user ID is not used to route SIP messages, there is no NP problem for the private user ID. The public user identity is used as a contact address for communicating with other users, similar to a telephone number referred to in traditional telecommunication networks such as the PSTN. The user public identifier adopts the format of SIP URI or Tel URI. Tel URI is defined in protocol RFC 3966, and the type can be "+86 755 12345678". SIP URI is defined in protocol RFC 3261, and the type can be "sip: alice@OperatorA.com". Since the public user ID contains routing information, there is an NP problem in the public user ID.

The demand for the number NP service still exists in the IMS network, and users often do not want to change the original user public identity because of changing operators. For example, a user under operator A (whose public user ID is: sip:alice@OperatorA.com), now wants to change to operator B to provide services, and is usually willing to keep this contact information (alice@OperatorA.com) unchanged Otherwise, they have to notify their colleagues, friends and relatives one by one.

According to the routing rules of IMS, only the public user ID assigned by the user's current operator is used for routing. When the user changes the operator, the user still needs to be assigned a new user public ID (such as alice@OperatorB. com), otherwise, if the public user ID assigned by the previous operator is still used, the call to this user will be sent to the user's previous operator without any special processing. According to the description of the RFC3482 protocol, there must be a database in the calling network or the user's previous operator network, which is used to convert the user's old address (the user's public identifier assigned by the operator to which the user previously belonged) to the user's new address (the user public identity assigned by the operator to which the user currently belongs) or other equivalent routing information, the call can finally be connected to the called user. This database is called NPDB (Number Portability Data Base).

One of the routing methods of IMS is SIP redirection, which means that the receiver of the session returns a message to the initiator of the call, informing the initiator of the session of the current real address of the called party, so that the initiator of the session can find the receiver correctly. This communication connection method is called redirection. Let me illustrate with an example: Xiao Wang, a child of Wang’s family, called Xiao Zhang, a child of Zhang’s family, but Xiao Zhang went to Li’s house, and it was Xiao Zhang’s father who answered the phone. Xiao Zhang’s father told Xiao Wang, You can find Xiao Zhang by calling Li's home, and here Xiao Zhang's father shows the redirection function.

Filtering rule FC is a concept of IMS network, it can be a part of user subscription data stored in HSS. Its function is: if the user has set a filtering rule, when a session about this user is generated, the filtering rule will be It is used by the S-CSCF to decide whether the session should be forwarded to the application server AS indicated by the filter rule for processing. This is helpful for flexible session processing.

Public service identifier PSI is another concept of IMS network. PSI is used to identify various services in AS. The type of PSI is SIP URI or tel URI. The information of PSI is stored in HSS. PSI will be associated with AS. When When there is a session with this PSI as the target address, when the I-CSCF performs data query to the HSS, the HSS will return the address of the AS to the I-CSCF in the response message, so that the I-CSCF can route the session to the relevant AS. This AS performs business processing.

The current NP scheme is mainly the NP scheme for the circuit domain CS network described in RFC3482. One of the schemes is OR (Onward Routing), as shown in Figure 1. This scheme includes the following steps:

1. When a call is generated (the called party of this call is an NP user), the network where the calling party is located will route the call to the network where the NP user signed up for the first time according to the default routing rules;

2 to 3. The network that the NP user signed for the first time queries the NPDB, performs NP address conversion, and obtains new routing information;

4. Finally, the call is routed to the network that the NP user currently subscribes to.

The above process was designed for the circuit domain network at that time. Since the basic structure of the IMS network is very different from that of the traditional circuit domain network, the existing NP solution cannot meet the needs of the IMS network, mainly in the signaling process and bearer in the way of establishment.

IMS is based on SIP signaling. When the caller initiates a session request to the network that the NP user subscribes to for the first time, the network that the NP user subscribes to for the first time can not only forward the session request to the network that the NP user currently subscribes to, but also The network where it is located sends a redirection message to let the calling network directly send a session request to the network that the NP user is currently subscribed to, so the signaling process of the NP service in the circuit domain is not as flexible as the IMS network;

In terms of the bearer establishment method, under IMS, the bearer between the calling party and the called party no longer needs to be connected through the network tandem (i.e., transit) signed by the NP user for the first time, but can be established directly between the calling network and the called network. , so in the processing of NP services, the circuit domain network is not as good as the IMS network in terms of the utilization efficiency of bearer resources.

To sum up, there is no number portability mechanism in the current IMS system, which is an important deficiency in the application services of the IMS system.

Contents of the invention

The invention provides a system for realizing the number portability service, a number portability application server, a number portability service trigger logic device and a method for realizing the number portability service, so as to solve the problem that there is no number portability mechanism in the current IMS system.

The system for implementing the number portability service of the present invention includes: the home subscriber server HSS, and the number portability database NPDB, which stores the difference between the address assigned by the called user's first subscription network and the address assigned by the user's current subscription network. Correspondence between;

The number portability NP service trigger logic device is used to forward the session request to the number portability application server NP-AS through the HSS according to the built-in logic of the device;

NP-AS, used to convert the address assigned by the called user's first contract network to the address assigned by the user's current contract network, and directly complete session routing according to the address, or redirect the address to the called user The first time you sign up with the network to complete session routing.

The NPDB is set in the NP-AS, or is independent from the NP-AS.

The NPDB is set in the service control function point SCP.

The NPDB is a domain name server DNS.

The NP-AS includes: an NP service control module, configured to interact with the NPDB to obtain the address assigned by the called user's current subscription network; and directly complete session routing according to the address, or redirect the address to the called The first time a user signs up with the network to complete session routing.

If the NPDB is set in the NP-AS, a private interface is used between the NP service control module and the NPDB. If the NPDB is set in the SCP, the NP service control module is connected to the NPDB through the CAP interface through the IM-SSF module.

The built-in logic of the NP service trigger logic device is to simulate the NP-AS as the serving call session control function entity S-CSCF in the called network, and designate the S-CSCF as the called user in the HSS The corresponding S-CSCF; or the built-in logic of the NP service trigger logic device is to use the public user identity of the user who changes the subscription network as the public service identity PSI in the HSS, and point the PSI to the NP-AS; or The built-in logic of the NP service triggering logic device is to reserve the subscription data of the user who changes the subscription network in the HSS, and register the filtering rules, so that the corresponding S-CSCF sends the session request to the NP-AS.

The inventive method comprises the following steps:

A. The number portability NP service trigger logic device forwards the session request to the number portability application server NP-AS according to its built-in logic;

B. The NP-AS uses the address information in the session request to query the address allocated by the called user's current subscription network;

C. The NP-AS converts the address assigned by the called user's first subscription network to the address assigned by the user's current subscription network, and directly completes session routing with this address, or redirects the address to the calling party side, the calling side completes session routing with this address.

The built-in logic of the NP service trigger logic device is to simulate the NP-AS as the S-CSCF in the called network, and designate the S-CSCF as the S-CSCF corresponding to the called user in the HSS;

Or the built-in logic of the NP service trigger logic device is to use the public user identity of the user who changes the subscription network as PSI in the HSS, and point the PSI to the NP-AS;

Or the built-in logic of the NP service trigger logic device is to reserve the subscription data of the user who changes the subscription network in the HSS, and register the filtering rules, so that the corresponding S-CSCF sends the session request to the NP-AS.

The HSS is the HSS in the network that the user subscribes to for the first time.

If the address that is inquired is a SIP URI mark, then the described direct completion of session routing with this address includes the following steps: the NP-AS performs domain name resolution on the SIP URI mark to obtain routing information therefrom; The address is carried in the session request and sent with the routing information; the called user's current subscription network receives the session request.

If the address that has been inquired is a tel URI mark, then the described direct completion of the session routing with the address includes the following steps: the NP-AS performs an ENUM query on the tel URI mark; if the query is successful, the information obtained from the query obtain routing information; carry the queried address in the session request, and send it with the routing information; the called user's current subscription network receives the session request.

If the ENUM query fails, redirect the queried address to the calling side, and the calling side uses this address to complete session routing.

The beneficial effects of the present invention are as follows:

The present invention adds an NP service trigger logic device and an NP-AS to the existing IMS network, and the NP service trigger logic device is used to forward the session request to the NP-AS according to the built-in logic of the device; the NP-AS It is used to convert the address assigned by the called user's first subscription network to the address assigned by the user's current subscription network, so that the session routing can be completed normally. By combining the above two network elements with the existing IMS network, a number portability mechanism is provided for the IMS network.

Applying the above system and device, the present invention also provides a method for realizing the number portability service.

On the basis of the framework stipulated by IMS, the present invention not only realizes the NP function under IMS, but also integrates the existing processing mechanism of IMS as much as possible in the way of realization, so that operators can easily add NP function on the basis of existing equipment . Therefore, the present invention has outstanding advantages in implementability.

Description of drawings

FIG. 1 is a schematic structural diagram of a circuit domain number portability system;

Fig. 2 is a schematic structural diagram of the number portability system of the present invention;

Fig. 3 is a schematic structural diagram of the number portability application server of the present invention;

Fig. 4 is a flow chart of the method of the present invention;

Figure 5 is a signaling flow chart for users to register initial filtering rules so that session requests are forwarded to NP-AS and directly complete session routing;

Fig. 6 is a signaling flow chart of using the user's public user identity as the PSI, pointing to the NP-AS, and redirecting to complete session routing.

Detailed ways

In order to enable the IMS system to provide number portability (NP) services, the present invention provides a system for implementing number portability services, as shown in Figure 2, which includes: the network that the NP user subscribes to for the first time and the network that the user currently subscribes to .

The network where the NP user signs up for the first time includes the sequentially connected number portability database NPDB, number portability application server NP-AS, number portability NP service trigger logic device, I-CSCF and S-CSCF, and home subscriber server HSS ; The NP service trigger logic device is also connected to the HSS.

The I-CSCF and S-CSCF are used to query the HSS for subscription information of the user, and determine a route according to the obtained subscription information.

The NP service triggering logic device has logic inside it, and the logic makes the subscription information provided by the HSS for the I-CSCF finally point to the NP-AS, so that the session request is forwarded to the NP-AS. The present invention provides three kinds of logics but not limited to three kinds. The logic is to simulate the NP-AS as a serving call session control function entity S-CSCF in the called network, and designate the S-CSCF as the S-CSCF corresponding to the called user in the HSS. Or, the logic is to use the public user identity of the user changing the subscription network as the public service identity PSI in the HSS, and point the PSI to the NP-AS. Or, the logic is to reserve the subscription data of the user who changes the subscription network in the HSS, and register a filter rule, so that the corresponding S-CSCF sends the session request to the NP-AS.

The NPDB stores the correspondence between the address assigned by the called user's first subscription network (old public user ID) and the address (new public user ID) assigned by the user's current subscription network. The NPDB It can be set in the NP-AS or in the service control function point SCP. Since the domain name server DNS can record the corresponding relationship between the old and new public user IDs, the DNS can also be used to realize the NPDB function. The NPDB is used by the IMS Network exclusive, or shared by at least one network.

The NP-AS is provided with an NP service control module, which is used to interact with the NPDB to obtain the address allocated by the called user's current subscription network; The allocated address is converted to the address allocated by the user's current subscription network to directly complete the session routing, or the address is redirected to the called user's first subscription network to complete the session routing. If the NPDB is set in the NP-AS, then a private interface is used between the NP service control module and the NPDB to complete address interaction (that is, the old and new public user identification interaction); if the NPDB is set in the SCP, the The NP service control module is connected to the NPDB through the CAP interface through the IM-SSF module.

Corresponding to the above-mentioned system, the present invention provides a number portability application server, as shown in FIG. 3 , which is provided with an NP service control module, and can further have a built-in NPDB.

The NP service control module is used to interact with NPDB to obtain the address assigned by the called user's current subscription network; and directly complete session routing according to the address, or redirect the address to the called user's first subscription network The network on which the address is assigned to complete session routing.

The NPDB stores the corresponding relationship between the address assigned by the called user's first subscription network and the address assigned by the user's current subscription network.

Corresponding to the above system, the present invention also provides a number portability service trigger logic device, which is provided with logic for forwarding the session request to the number portability application server NP-AS. The logic is the same as described in the above system.

Applying the above-mentioned system and device, the present invention provides a method for realizing the number portability service, as shown in Figure 4, which includes the following steps:

S1. The I-CSCF queries the HSS for user subscription information.

S2. The NP service trigger logic device forwards the session request to the NP-AS according to its built-in logic.

S3. The NP-AS inquires about the address allocated by the called user's current subscription network according to the address information in the session request.

S4. Complete session routing with the address allocated by the called user's current subscription network.

The method of the present invention is specifically described below through three examples.

Method example 1: register initial filtering rules for users, so that session requests are forwarded to NP-AS, and session routing is directly completed.

Assume that the called user originally belonged to IMS operator A (its public user ID is: Alice@AAA.COM), and now the user changes the operator and signs to another IMS operator B, and the user's shared user ID remains unchanged. However, in order to enable the correct routing of the session to be connected to the user, the newly contracted operator B assigns another public user identity (Alice@BBB.COM) to the user. Operator A registers an initial filtering rule for the user, and directs the session request sent to the user to the NP-AS.

The calling user is an IMS user, or other network users.

Referring to Fig. 5 and in conjunction with Fig. 4, this example includes the following specific processes (note: in order to highlight the main process, some secondary messages are not drawn in Fig. 5, such as 180, 100"):

S101. The I-CSCF queries the HSS for user subscription information.

1. When the calling user initiates a session request to the called user, according to the default routing rules, the session will be routed to the I-CSCF of the network (operator A) that the called user signed for the first time;

2. After receiving the session request, the I-CSCF queries the HSS of operator A for the user's subscription data.

S102. The NP service trigger logic device forwards the session request to the NP-AS according to its built-in logic.

In this example, the built-in logic of the NP service triggering logic device is to reserve the subscription data of the user who changes the subscription network in the HSS of operator A, and register the filtering rules, so that the corresponding S-CSCF will send the session request sent to the NP-AS.

3. Since the called user has changed the subscription network, he is no longer a registered user of operator A. Therefore, the HSS returns the capability information of the S-CSCF to be selected to the I-CSCF for the I-CSCF to select an S-CSCF; the capability information of the S-CSCF returned by the HSS to the I-CSCF is selected according to the logic , that is, any selected S-CSCF will directly forward the session request to the NP-AS;

4. The I-CSCF selects an S-CSCF, and routes the session request to the selected S-CSCF;

5. The S-CSCF routes the session request to the NP-AS.

S103. The NP-AS inquires about the address allocated by the called user's current subscription network according to the address information in the session request.

6. After the NP-AS receives the session request, it extracts the address information in the session request (the address assigned by the operator A to the user, Alice@AAA.COM), and sends the address information to the NPDB with its built-in NP service control module. Query the address assigned by the corresponding called user's current subscription network (Alice@BBB.COM);

7. The NPDB returns the address Alice@BBB.COM assigned to the user by the carrier B currently signed by the user.

S104. Complete session routing with the address allocated by the called user's current subscription network.

8. The NP service control module in the NP-AS converts the address allocated to the user by the operator A in the session request to the address allocated by the operator B currently contracted by the user, and directly converts the converted session The request is routed to the network B to which the NP user is currently subscribed.

In this example, the address assigned by the user's current subscription network returned by the NPDB is a SIP URI identifier, and the NP-AS performs domain name resolution on the SIP URI identifier to obtain routing information (I-CSCF address of operator B) therefrom. ; carry the address in the session request, and send it with the routing information; the called user's current subscription network receives the session request.

If the address assigned by the user's current contracted network returned by the NPDB is a tel URI mark, then the NP-AS performs an ENUM query on the tel URI mark; if the query is successful, then obtains the routing information from the inquired information; The address is carried in the session request and sent with the routing information; the called user's current subscription network receives the session request. If the ENUM query fails, the address is redirected to the calling side, and the calling side uses the address to complete session routing.

Method example 2: use the user's public user ID as the PSI, point to the NP-AS, and redirect to complete session routing.

Assume that a user originally belonging to IMS operator A (whose public user ID is +86-755-12345678), now the user changes operators and signs to a CS operator B, and the user's public user ID remains unchanged. But in order to enable the correct routing of the session to be connected to the user, the newly contracted operator B assigns another public user ID (+86-755-87654321) to the user. Operator A registers a PSI with the user's public user identity (+86-755-12345678), and points to the NP-AS.

The calling user is from a CS operator (or an IMS operator).

Referring to Fig. 6 and in conjunction with Fig. 4, this example includes the following specific processes (note: in order to highlight the main process, some secondary messages are not drawn in Fig. 6, such as 180, 100"):

S201. The I-CSCF queries the HSS for user subscription information.

1. When the calling user initiates a session request to the called user, according to the default routing rules, the session will be routed to the MGCF of the network (operator A) that the called user signed for the first time;

2. The MGCF sends the session request to the I-CSCF;

3. After receiving the session request, the I-CSCF queries the HSS of operator A for the user's subscription data.

S202. The NP service trigger logic device forwards the session request to the NP-AS according to its built-in logic.

In this example, the built-in logic of the NP service trigger logic device is to use the public user identity of the user changing the subscription network as PSI in the HSS, and point the PSI to the NP-AS.

4. The HSS returns the query result to the I-CSCF, which indicates that the called number is a PSI, and also indicates the AS corresponding to the PSI in the result;

5. After receiving the query result, the I-CSCF routes the session request to the NP-AS.

S203. The NP-AS searches for the address allocated by the called user's current subscription network according to the address information in the session request.

6. After the NP-AS receives the session request, it extracts the address information in the session request (the address assigned by operator A to the user, +86-755-12345678), and uses its built-in NP service control module to send NPDB queries the address assigned by the corresponding called user's current subscription network (+86-755-87654321);

7. NPDB returns the address assigned by the operator B currently signed by the user +86-755-87654321 (it can be a new number assigned by the new operator, or a number that can be routed to the new operator A new number composed of a prefix and the original number).

S204. Complete session routing with the address allocated by the called user's current subscription network.

8 to 9. The service control module of the NP-AS converts the address allocated to the user by the operator A in the session request to the address allocated to the user by the operator B currently contracted by the user. In this example, the address assigned by the user's current subscription network returned by the NPDB is a tel URI identifier, and then the NP-AS performs an ENUM query on the tel URI identifier. Since the called user is currently subscribed to the CS network, the ENUM query must fail. Afterwards, the NP-AS redirects the converted session request to the I-CSCF of operator A, and then the I-CSCF redirects the session request to the MGCF of operator A.

10. The MGCF sends the session request to the network B currently subscribed by the called user to complete session routing.

Method Example 3: The NP-AS is simulated as the S-CSCF in the called network, so that the session request is forwarded to the NP-AS and redirected to complete session routing.

The assumptions in this example are the same as those in Method Example 2.

S301. The I-CSCF queries the HSS for user subscription information. (same as step S201)

S302. The NP service trigger logic device forwards the session request to the NP-AS according to its built-in logic.

In this example, the built-in logic of the NP service trigger logic device is to simulate the NP-AS as the S-CSCF in the called network, and designate the S-CSCF in the HSS as the corresponding The S-CSCF.

Since the called user has changed the subscription network, he is no longer a registered user of operator A. Therefore, the HSS returns to the I-CSCF unique S-CSCF information (which can be realized by setting filtering rules in the HSS), that is, the NP-AS;

After receiving the query result, the I-CSCF routes the session request to the S-CSCF provided by the HSS, that is, routes the session request to the NP-AS.

S303, NP-AS uses the address information in the session request to query the address allocated by the called user's current subscription network. (Same as step S203)

S304. Complete session routing with the address allocated by the called user's current subscription network. (same as step S204)

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (19)

1. A system for implementing number portability services, comprising: a home subscriber server HSS, and a number portability database NPDB, which stores the address assigned by the called user's first subscription network and the address assigned by the user's current subscription network Correspondence between; It is characterized in that the system also includes: The number portability NP service trigger logic device is used to forward the session request to the number portability application server NP-AS through the HSS according to the built-in logic of the device; NP-AS, used to convert the address assigned by the called user's first contract network to the address assigned by the user's current contract network, and directly complete session routing according to the address, or redirect the address to the called user's Sign up to the network for the first time to complete session routing. 2. The system according to claim 1, wherein the NP-AS comprises: The NP service control module is used to interact with the NPDB to obtain the address assigned by the called user's current subscription network; and directly complete session routing according to the address, or redirect the address to the called user's first subscription network , to complete session routing. 3. The system according to claim 2, wherein the built-in logic of the NP service trigger logic device is to simulate the NP-AS as a serving call session control function entity S-CSCF in the called network, and The S-CSCF is designated in the HSS as the S-CSCF corresponding to the called user. 4. The system according to claim 2, wherein the built-in logic of the NP service trigger logic device is to use the public user identification of the user who changes the subscription network as the public service identification PSI in the HSS, and point the PSI to The NP-AS. 5. The system according to claim 2, wherein the built-in logic of the NP service trigger logic device is to reserve the subscription data of the user who changes the subscription network in the HSS, and register the filtering rules so that the corresponding S- CSCF sends the session request to the NP-AS. 6. The system according to claim 2, wherein the NPDB is set in the NP-AS, or is independent from the NP-AS. 7. The system according to claim 6, wherein if the NPDB is set in the NP-AS, a private interface is used between the NP service control module and the NPDB. 8. The system according to claim 2, wherein the NPDB is set in a Service Control Function Point (SCP). 9. The system according to claim 8, wherein the NP service control module is connected to the NPDB through the CAP interface through the IM-SSF module. 10. The system according to claim 2, wherein the NPDB is a domain name server (DNS). 11. The system according to any one of claims 1 to 10, wherein the NPDB is exclusively shared by the IMS network, or shared by at least one network. 12. A method for realizing number portability services, comprising the following steps: A. The number portability NP service trigger logic device forwards the session request to the number portability application server NP-AS according to its built-in logic; B. The NP-AS uses the address information in the session request to query the address allocated by the called user's current subscription network; C. The NP-AS converts the address allocated by the called user's first contract network to the address allocated by the user's current contract network, and directly completes session routing with this address, or redirects the address to the calling party side, the calling side completes session routing with this address. 13. The method according to claim 12, wherein the built-in logic of the NP service trigger logic device is to simulate the NP-AS as the S-CSCF in the called network, and set the S-CSCF in the HSS - The CSCF is designated as the S-CSCF corresponding to the called user. 14. The method according to claim 12, wherein the built-in logic of the NP service trigger logic device is to use the public user identity of the user who changes the subscription network as the PSI in the HSS, and point the PSI to the NP -AS. 15. The method according to claim 12, characterized in that, the built-in logic of the NP service trigger logic device is to reserve the subscription data of the user who changes the subscription network in the HSS, and register the filtering rules so that the corresponding S- CSCF sends the session request to the NP-AS. 16. The method according to any one of claims 13 to 15, wherein the HSS is the HSS in the network that the user subscribes to for the first time. 17. The method according to claim 12, wherein if the queried address is a SIPURI identifier, then said directly completing session routing with the address comprises the following steps: -The NP-AS performs domain name resolution on the SIP URI identifier, and obtains routing information therefrom; - carry the queried address in the session request, and send it with the routing information; - the called user's current subscription network receives the session request. 18. The method according to claim 12, wherein if the queried address is a telURI identifier, then said directly completing session routing with the address comprises the following steps: -The NP-AS performs an ENUM query on the tel URI identifier; - If the query is successful, the routing information is obtained from the queried information; - carry the queried address in the session request, and send it with the routing information; - the called user's current subscription network receives the session request. 19. The method according to claim 18, wherein if the ENUM query fails, the queried address is redirected to the calling side, and the calling side uses the address to complete session routing.

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