WO2005060155A1

WO2005060155A1 - A system and method for providing the network service to the users in next generation network (ngn)

Info

Publication number: WO2005060155A1
Application number: PCT/CN2004/001475
Authority: WO
Inventors: Qingsong Jiang; Dongming Zhu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2003-12-19
Filing date: 2004-12-20
Publication date: 2005-06-30
Also published as: CN1630409A; CN100366124C

Abstract

The present invention discloses a system and method for providing the network service to the users in NGN. The System includes each call processing unit in NGN and the centralized user database which stores the user data of the users in NGN, wherein the centralized user database is used to obtain the stored user data of said user alter receiving the user data information of the requesting user transmitted by the call processing unit and transmit the user data to the call processing unit; the call processing unit is used to transmit the user data information of the requesting user to the centralized user database and access the call processing unit corresponding to the user data of said user received from the centralized user database, thereby providing the network service to said user. The system and the method can realize the mobility of the users, access the network service more flexibly and conveniently in NGN and realize the wide area network service of the users.

Description

System and method for providing network services to users in next generation network

The present invention relates to the field of providing next-generation networks (NGN) of C4 / C5 services and Internet Protocol (IP) multimedia services for fixed network users, and particularly to a system and method for providing network services to users in NGN. Background of the invention

With the development of the network, NGN appeared. NGN uses the fixed network network architecture to connect the fixed network to external networks, such as: connecting the fixed network to a network that provides packet data services, and providing C4 / C5 services and IP multimedia services to users in the fixed network.

Compared to mobile networks, one of the biggest differences in NGN is that user data is stored in the call processing unit of the user's area. Since the user data includes the user's subscription information and authentication information, etc., when the user wants to receive network services through NGN, he must obtain the user data from the call processing unit in his area, so as to know whether he has permission to access NGN, and Determine the type of network service business that is allowed to accept, so currently, users can only access NGN and obtain network services through the call processing unit in their area. Information can be exchanged between the call processing units, and external networks can be accessed through the gateway. When the user initiates an access request and requests a network service, the call processing unit in the area where the user is located obtains the user data of the user stored by itself, performs information interaction with other call processing units, or accesses the external network through the gateway. Complete the access requested by the user and provide the network service requested by the user.

This method of storing user data in the call processing unit of the user's current area has the following disadvantages. First, because user data of users in different regions is stored in call processing units in different regions, when a user moves from the region where he is currently located to other regions, in order to enable the user to still obtain network services in NGN after having moved, The following process must be performed: The call processing unit in the area where the user is currently located deletes the user data of the user stored by the user, and then the call processing unit in the area to which the user is to move stores the user data of the user again.

The above process requires manual deletion or addition of user data in the call processing unit, which is very tedious and inconvenient, and hinders users from implementing the nomadic characteristics of the user. Nomadic characteristics mean that fixed network users can Restricted mobility characteristics.

Secondly, since user data of users in different areas are stored in call processing units in different areas, in order to complete the network service of the called user, the call processing unit in the area where the calling user is located must go to the call processing unit in the area where the called user is located. The user data of the called user is acquired, and then processed according to the user data of the called user. Therefore, the call processing unit in the area where the calling user is located cannot know the user data of the called user in advance and perform optimization processing in advance according to the user data, thereby avoiding routing detours and consumption of NGN bandwidth resources, so that the calling user can pass NGN. It is inflexible and inconvenient to provide network services to the called user.

Finally, since user data of users in different regions are stored in call processing units in different regions, user authentication must also be performed in different call processing units. It is inflexible and inconvenient for users to receive network services through NGN.

In summary, how to realize the nomadic characteristics of users in NGN, and make it more flexible and convenient for users to receive network services in NGN has become an urgent problem. Summary of the invention

In view of this, the main object of the present invention is to provide a system and method for providing network services to users in NGN. The system and method can realize the nomadic characteristics of users and allow It is more flexible and convenient for users to receive network services in NGN.

According to the above purpose, the technical solution of the present invention is implemented as follows:

A system for providing users with network services in a next-generation network. The system includes call processing units connected to each other in the next-generation network. The system also includes a centralized user database that stores user data for users of the next-generation network. Each call processing unit in the network is connected, and is used for receiving the user data information of the requesting user sent by the call processing unit, and then acquiring the stored user data of the user and sending it to the call processing unit;

The call processing unit is configured to send user data information of the requesting user to the centralized user database, and provide network services for the user according to the user data of the user received from the centralized user database.

The system further includes a call processing unit that does not belong to the next generation network, the centralized user database is connected to the call processing unit that does not belong to the next generation network, and is configured to receive user data information of the requesting user sent by the call processing unit, Obtaining the stored user data of the user and sending it to the call processing unit;

The call processing unit that does not belong to the next generation network is configured to send user data information of the requesting user to the centralized user database, and provide network services for the user according to the user data of the user received from the centralized user database.

A method for providing network services to users in a next-generation network. A centralized user database for storing user data of users of the next-generation network is set in the next-generation network. The method includes:

The call processing unit obtains user data of the user from the centralized user database, and provides network services for the user according to the obtained user data.

The user data is subscription information, routing information, and authentication information of the user.

The subscription information includes: one or more of a subscriber number, a network subscription service subscribed by the subscriber, and network element information capable of providing subscriber subscription service control; The authentication data includes: one or more of a user ID, a user key, a user account, and a user account password;

The routing information includes: one or more of a telephone number resource number suggested address, a uniform resource locator address, and an Internet protocol address of the International Telecommunication Union Telecommunication Standardization Committee E.164 of the called roaming user.

The user is a roaming user, and the process of obtaining user data of the user is:

All. The roaming user sends a registration request to the centralized user database through the call processing unit in the current area;

A12. The centralized user database obtains the call processing unit registered by the roaming user from the user data of the roaming user stored in the centralized user database, instructs the registered call processing unit to delete the stored user data of the roaming user, and deletes the roaming user. The registered call processing unit record is updated to the call processing unit in the area where the roaming user is currently located, and sends the user data of the roaming user to the call processing unit in the area where the roaming user is currently located;

A13. The call processing unit in the area where the roaming user is currently located stores the user data of the roaming user.

The process of instructing the registered call processing unit to delete the stored user data of the roaming user as described in step A12 is:

The centralized user database sends a request to delete the roaming user data to the registered call processing unit, and the registered call processing unit deletes the user data of the roaming user stored by itself.

A dynamic database is set in the call processing unit in the area where the roaming user is currently located, and the user data of the roaming user described in step A13 is stored in the set dynamic database.

In step A11, the registration request is sent through one of the mobile application part protocol, the integrated service data network user part protocol, and the diameter protocol;

The user data of the roaming user described in step A12 passes the mobile application part protocol, comprehensive Send one of the user part agreement and diameter agreement of the service data network.

The users are traditional analog telephone users, integrated service digital network users, high-speed digital user loop users, and intelligent multimedia accessing SIP / H.323 through the Internet protocol through the media gateway and integrated service access equipment. An item in the terminal.

The user is a called roaming user, and the process of obtaining user data of the user is:

A21: The calling user sends a routing message requesting the called roaming user to the centralized user database through the calling-side call processing unit, where the message carries the identity of the called roaming user;

A22. The centralized user database obtains the routing information in the user data of the called roaming user stored in the message according to the identity of the called roaming user carried in the message, and obtains the called party from the call processing unit in the area where the called roaming user is currently located. The temporary identification of the roaming user, and sending the temporary identification and routing information to the calling-side call processing unit;

The process of providing network services for the user is:

A23. The calling-side call processing unit determines a route to the called roaming user according to the received routing information and the temporary identification, and establishes communication between the calling user and the called roaming user.

The process of obtaining the temporary identity of the called roaming user described in step A22 is:

A221: The centralized user database determines the call processing unit of the area where the called roaming user is currently located according to the user data of the called roaming user stored therein, and sends a message requesting to provide a temporary identification to the call processing unit of the area where the called roaming user is currently located. ;

A222. The call processing unit receiving the message allocates a temporary identification to the called roaming user, and sends the allocated temporary identification to a centralized user database.

The user is a roaming user. Before step A, the method further includes an authentication process:

A31. The roaming user initiates an authentication request to the centralized user database through the call processing unit in the current area;

A32. The centralized user database obtains the user key of the roaming user from the user data of the roaming user stored in the centralized user database and generates a random number, and uses the random number and the user key to pass The authentication algorithm obtains the authentication value, and sends the authentication value and the random number to the call processing unit in the area where the roaming user is currently located, and the call processing unit sends the random number to the roaming user;

A33. The roaming user uses the received random number and the user key stored in the roaming user to obtain another authentication value through an authentication algorithm, and sends the authentication value to the call processing unit in the area where the roaming user is currently located.

A34. The call processing unit in the area where the roaming user is currently located compares whether the two authentication values are the same. If the two authentication values are the same, step A is performed. Otherwise, it is determined that the authentication fails, and the process ends.

When the user is a roaming user, before the call processing unit obtains user data of the user from the centralized user database, the method further includes an authentication process:

A41. The roaming user sends a request for rights to the centralized user database through the call processing unit in the current area, and the roaming user sends the user account and account password stored by the roaming user to the call processing unit in the current area;

A42. The centralized user database obtains the user account and account password from the user data of the roaming user stored in the centralized user database, and sends the user account and account password to the call processing unit in the area where the roaming user is currently located.

A43. The current call processing unit of the roaming user compares whether the two user accounts and account passwords are the same. If they are the same, step A is performed. Otherwise, it is determined that the authentication fails, and the process ends.

As can be seen from the above solution, the present invention sets a centralized user database in the NGN, and the centralized user database stores user data of all users in the NGN. When a user moves to another area, first the centralized user database instructs the call processing unit in the area where the user was located to delete the saved user data of the user; then the centralized user database updates the registered call processing unit of the user; finally the user The call processing unit in the current area obtains and saves the user data of the user from a centralized user database. This method enables the user to still receive network services in the area after moving, and realizes the nomadic characteristics of the user.

The system and method provided by the present invention have the following advantages: First, the present invention not only does not need to manually add user data of a user to a call processing unit in a region where the user is currently located, or manually deletes the call processing unit in the region where the user is located before moving, and because the centralized user database stores For all user data of users in NGN, the call processing unit in the area where the user is currently located can obtain the user data of the user from the centralized user database, so that NGN can provide network services for the mobile users.

Secondly, the calling-side call processing unit can obtain the user data as the called user in the communication by accessing the centralized user database in advance, and perform priority processing.

Finally, the call processing unit that the roaming user requests to access can authenticate the roaming user that requires access through information interaction with the centralized user database, so as to confirm the access rights of the roaming user, and ensure that NGN network resources are not illegally occupied.

In summary, the system and method provided by the present invention can realize the nomadic characteristics of users in NGN, and provide network services for users in NGN more flexibly and conveniently. Brief description of the drawings

FIG. 1 is a schematic diagram of a system for providing network services to users according to the present invention.

FIG. 2 is a flowchart of registration performed by a user of the present invention after roaming to other areas. FIG. 3 is a flowchart of providing a current route for a user according to the present invention.

FIG. 4 is a flowchart of authenticating a user by using user data stored in a centralized user database according to the present invention. Mode of Carrying Out the Invention

In order to achieve the objectives, technical solutions, and advantages of the present invention, the following further describes the present invention in detail with reference to the embodiments and the accompanying drawings.

A user who moves from the registered call processing unit management area to other call processing unit management areas is referred to as a roaming user. In the prior art, a user's subscriber number and usage The user data is bound to the call processing unit, and the call processing unit in the area where the user is registered stores the user data of the user. In the present invention, the user number and user data of the user are separated from the call processing unit to implement the user's Nomadic characteristics.

FIG. 1 is a schematic diagram of a system for providing users with network services according to the present invention: The system includes an NGN in the prior art, and the system adds a centralized user database in addition to the original multiple call processing units of the NGN. Among them, a plurality of call processing units are call processing unit 1, call processing unit 2, ... call processing unit N, and these call units can also perform information interaction as described in the prior art; the centralized user database storage is originally stored in each call processing and distributed User data for NGN users in the list.

When the call processing unit is to provide network services for the user, the call processing unit 1, the call processing unit 2, ..., or the call processing unit N sends the information requesting the user data to the centralized user database. After the centralized user database receives the information, The stored corresponding user data is acquired and sent to the call processing unit that issued the information.

The call processing unit that does not belong to the NGN may also obtain the user data of the user from the centralized user database by sending the user data information requesting the NGN user.

The centralized user database provided in the NGN of the present invention is used to store user data of all users of the NGN, and the user data includes subscription information, authentication information, and routing information. The contract information includes relevant data about the user's subscription, such as: the network service to which the user is subscribed, other network element address information that provides data or services to the user, and the user's phone number. The authentication information includes the user's identification, the user's key, the user's account, and the user's account password. The routing information includes the International Telecommunication Union Telecommunication Standardization Committee E.164 telephone number resource number suggested address, Uniform Resource Locator (URL) address and IP address of the called roaming user.

The centralized database can also store the user data of the user in the call processing unit that the user requests to access; or according to the setting of the call processing unit management area registered by the user in the subscription information and the call processing unit management area of the current location, Choose to provide this user The call processing unit of the network service, and stores the user data in the selected call processing unit.

The invention also sets up a dynamic database in the call processing unit. The dynamic database is used to store user data of the roaming user. The data structure of the stored user data of the roaming user is the same as the data structure of the user data already stored in the call processing unit. The size of the dynamic database determines the number of roaming users that can be processed by this call processing unit to this area.

As shown in FIG. 2, FIG. 2 is a flowchart of registration performed by a user of the present invention after roaming to another area. The network entity involved in the registration includes a user, a call processing unit in the area where the user is currently located, and the user The centralized user database of the user data and the original call processing unit of the user registration area. The specific steps for this registration are:

Step 200: The user initiates a registration request to the call processing unit in the current area. Step 201: After receiving the request, the call processing unit forwards the request to a centralized user database.

Step 202: After receiving the request from the centralized user database, the original call processing unit of the user is obtained according to the stored subscription information in the user data of the user, and a request to delete the user data of the user is sent to the original call processing unit;

Step 203: After receiving the request, the original call processing unit deletes the user data of the user, and returns a successful response to the centralized user database.

Step 204: After receiving the response from the centralized user database, delete the record of the original call processing unit and the routing information to the original call processing unit in the user's user data, and use the call processing unit of the user's current area as the network service for the user. The call processing unit is stored in the user data of the user, determines the routing information of the user after roaming in the area where the user is currently located, and stores the routing information in the user data; centralized calls from the user database to the area where the user is currently located The processing unit sends a request to insert the user data, and the request carries User data of the user;

Step 205: After receiving the request, the call processing unit obtains user data of the user from the request, stores the user data of the user in a preset dynamic database, and sends a successful response to the centralized user database.

Step 206: After receiving the response, the centralized database sends a registration success response to the call processing unit of the user's current area;

Step 207: After receiving the response, the call processing unit forwards the registration success response to the user. The user successfully registers in the call processing unit in the current area, and can be allowed to receive network services through NGN at the roaming location, and obtain The same network services in the original call processing unit management area. These network services include: network services that perform information interaction with external networks, and network services that communicate with other users.

Another requirement for providing nomadic features for a user is to provide the user's current routing information for a network service request for the user. As shown in FIG. 3, FIG. 3 is a flowchart of the present invention for providing a user with a current route. The network entity includes a calling user, a calling-side call processing unit, a centralized user database, a called-side call processing unit, and a called user. Among them, the called user is a user with nomadic characteristics, that is, a called roaming user. The steps are as follows: Step 300: When the calling user wants to communicate with a user with nomadic characteristics through the calling-side call processing unit, the calling user sends a request for routing information to the centralized user database through the calling-side call processing unit. The request carries the user identification of the called user. Step 301: After receiving the request from the centralized user database, the stored user data of the called user is obtained according to the called user identification in the request, so as to obtain the called user. Routing information of call processing unit in current area, centralized user database The called-side call processing unit transmits a message requesting a temporary identifier;

Step 302: After receiving the message, the call processing unit on the called side allocates a temporary identity to the called user, and sends the temporary identity to the message response requesting the temporary identity and sends it to A centralized user database, and the role of the temporary identifier is to call the call processing unit on the called side to determine the called user according to the temporary identifier;

Step 303: After receiving the response from the centralized user database, a response to the routing information request is sent to the call processing unit on the calling side, and the response carries the routing information to the call processing unit of the area where the called user is currently located and the called user's Temporary identification

Step 304: After receiving the response, the calling-side call processing unit connects the calling user to the called-side call processing unit according to the routing information in the response and the temporary identity of the called user, and establishes a connection with the called-side call processing unit. For communication, the called side call processing unit determines the called user according to the temporary identity of the called user, and finally establishes communication between the calling user and the called user.

When the call processing unit in the area where the calling user is located accesses the centralized user database, the invention can obtain the subscription information in the user data of the called user from the centralized user database, thereby knowing which network service services the called user has subscribed to. What are the attributes of these network service businesses. Therefore, the call processing unit in the area where the calling user is located can perform optimization processing in advance according to the attributes of these network service services, without having to wait until the user data of the called user is obtained after accessing the call processing unit on the called side, and then perform the processing. deal with. The network service business attributes in the user data of these called users include: forwarding attributes, DND service attributes, and processing attributes of the calling-side call processing unit that needs special processing capabilities.

The invention also includes an authentication process for the network to confirm the user's access right when the user requests access, that is, a roaming user must be authenticated before being allowed to accept network services through NGN to ensure the legitimacy of user access and prevent network resources from being compromised. Illegal occupation. As shown in FIG. 4, FIG. 4 is a flowchart of authenticating a user by using user data stored in a centralized user database according to the present invention. The specific steps are as follows:

Step 400: The user sends an access request carrying a user identifier to the call processing unit in the current area;

Step 401: After receiving the request, the call processing unit obtains the user's A user identification, and the call processing unit sends an authentication request carrying the user identification to a centralized user database;

Step 402: After the centralized user database receives the authentication request, the authentication information in the stored user data of the user is obtained according to the user ID in the request, and the user's key is obtained from the authentication information. The centralized user database generates a random number, uses the random number and the key to obtain an authentication value according to a preset authentication algorithm, carries the random number and the authentication value in a response to the authentication request, and returns it to the sending authentication Call processing unit for rights request;

Step 403: After receiving the response, the call processing unit sends a random number in the response to the user.

Step 404: After receiving the random number, the user uses the random number and the stored key to obtain an authentication value according to a preset authentication algorithm, and sends the obtained authentication value to the current area. Call processing unit

Step 405: After receiving the authentication value sent by the user, the call processing unit compares the authentication value and the authentication value received from the centralized user database to determine whether they are the same. If they are the same, go to step 406; otherwise, Go to step 407;

Step 406: The call processing unit sends an authentication success message to the user, and allows network services to be provided to the user.

Step 407: The call processing unit sends an authentication failure message to the user, and it is not allowed to provide network services to the user.

When performing authentication, the above method may also be used to compare the user account and account password stored in the user data of the centralized user database with the user account and account password stored by the user itself in the call processing unit of the user's current area to determine Whether authentication is passed.

The information interaction between the centralized database and the call processing unit of the present invention can be completed by including but not limited to the following protocols: Integrated Service Data Network User Part (ISUP) protocol, Mobile Application Part (MAP) protocol, and Diameter protocol. These protocols support user bits Relevant technologies such as updating the registration of a set area, inserting user data of a user, access authentication of a user, and querying routing information of a user.

The users in the present invention are traditional analog telephone (POTS) users, integrated services digital network (ISDN) users, and high-speed digital user loop (xDSL) users accessed through media gateways (AG) and integrated service access equipment (IAD). Users or smart multimedia terminals that access SIP / H.323 through IP.

The method provided by the present invention can enable all users of NGN to implement unified authentication and authentication through a centralized user database, and the user's authentication and authentication is no longer limited by the area in which they are located, which increases the flexibility of user authentication. The method provided by the present invention can strip the user data of the user from the call processing unit in the current area, so that the user data can be "moved" in the call processing units in different areas, thereby solving the problem that NGN users can only be in a fixed area. Restrictions on enjoying network services. The method provided by the present invention uses a centralized user database to store user data, and provides conditions for the development of wide area network services among all NGN users. The method provided by the present invention introduces a centralized user database in NGN to uniformly store user data of NGN users. The centralized user database supports functions such as user data management, mobility management, routing provision, and security management with a call processing unit, so that In terms of network architecture, the substantial differences between NGN and mobile networks have been greatly reduced, providing the possibility of seamless integration of fixed and mobile equipment at the core network and business levels, and providing a bright future for all network service operators.

The method provided by the present invention can be applied to the following situations: Companies with frequently changing office locations, and occasions with large crowd mobility, such as in rental houses or campuses.

The above descriptions are merely preferred embodiments of the present invention, and are not intended to limit the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention shall be included in the protection of the present invention. Within range.

Claims

Claim

1. A system for providing users with network services in a next-generation network, the system including call processing units connected to each other in the next-generation network, characterized in that the system further includes a centralized storage of user data for users of the next-generation network The user database is connected to each call processing unit in the next generation network, and is configured to receive the stored user data of the user and send it to the call processing unit after receiving the user data information of the requesting user sent by the call processing unit; the call processing unit; Is configured to send user data information of the requesting user to the centralized user database, and provide network services for the user according to the user data of the user received from the centralized user database.

2. The system according to claim 1, further comprising a call processing unit that does not belong to the next generation network, and the centralized user database is connected to a call processing unit that does not belong to the next generation network, and is configured to receive After obtaining the user data information of the requesting user sent by the call processing unit, obtaining the stored user data of the user and sending it to the call processing unit;

3. A method for providing network services for users in a next generation network, characterized in that a centralized user database for storing user data of users of the next generation network is set in the next generation network, and the method includes:

4. The method according to claim 3, wherein the user data is user subscription information, routing information, and authentication information. .

5. The method according to claim 4, wherein the contract information comprises: One or more of a user number, a network service service subscribed by the user, and network element information capable of providing control of the user subscribe service;

The authentication data includes: one or more of a user ID, a user key, a user account, and a user account password;

6. The method according to claim 3, wherein the user is a roaming user, and the process of obtaining user data of the user is:

A 12. The centralized user database obtains the registered call processing unit of the roaming user from the user data of the roaming user stored in the centralized user database, instructs the registered call processing unit to delete the stored user data of the roaming user, and roams the roaming user. The call processing unit record registered by the user is updated to the call processing unit in the area where the roaming user is currently located, and the user data of the roaming user is sent to the call processing unit in the area where the roaming user is currently located;

7. The method according to claim 6, wherein the process of instructing the registered call processing unit to delete the stored user data of the roaming user in step A12 is: centralizing a user database to the registered call processing unit A user data deletion request for the roaming user is sent, and the registered call processing unit deletes the user data of the roaming user stored by itself.

8. The method according to claim 6, wherein a dynamic database is set in a call processing unit in the area where the roaming user is currently located, and the use of the roaming user as described in step A13 is performed. User data is stored in a set dynamic database.

9. The method according to claim 6, wherein the registration request in step A11 is sent through one of a mobile application part agreement, an integrated service data network user part agreement, and a diameter agreement;

The user data of the roaming user described in step A12 is sent through one of the mobile application part protocol, the integrated service data network user part protocol, and the diameter protocol.

10. The method according to claim 3, wherein the users are traditional analog telephone users, integrated service digital network users, high-speed digital user loop users, and users connected through media gateways and integrated service access devices. One of the intelligent multimedia terminals that access SIP / H.323 through the Internet protocol.

11. The method according to claim 3, wherein the user is a called roaming user, and the process of obtaining user data of the user is:

The process of providing network services for the user is:

12. The method according to claim 11, wherein the process of obtaining the temporary identity of the called roaming user in step A22 is:

A221: The centralized user database determines the call processing unit of the area where the called roaming user is currently located according to the user data of the called roaming user stored in the centralized user database, The call processing unit in the area sends a message requesting a temporary identification;

13. The method according to claim 3, wherein the user is a roaming user, and before step A, the method further comprises an authentication process:

A32. The centralized user database obtains the user key of the roaming user from the user data of the roaming user stored in the centralized user database and generates a random number, uses the random number and the user key to obtain an authentication value through an authentication algorithm, and uses the authentication value And the random number is sent to the call processing unit in the area where the roaming user is currently located, and the call processing unit sends the random number to the roaming user;

14. The method according to claim 3, wherein, when the user is a roaming user, before the call processing unit obtains user data of the user from the centralized user database, the method further comprises an authentication process:

A41. The roaming user initiates an authentication request to the centralized user database through the call processing unit in the current area, and the roaming user sends the user account and account password stored by the roaming user to the call processing unit in the current area;

A42: The centralized user database obtains the user account and account password from the user data of the roaming user stored in the centralized user database, and sends the user account and account password to the call processing unit in the area where the roaming user is currently located; A43. The current call processing unit of the roaming user compares whether the two user accounts and account passwords are the same. If they are the same, step A is performed. Otherwise, it is determined that the authentication fails, and the process ends.