WO2005083933A1

WO2005083933A1 - Method and systems for implementing data service prepayment in a cdma network

Info

Publication number: WO2005083933A1
Application number: PCT/CN2004/001571
Authority: WO
Inventors: Zheng Wang; Zhipeng Zheng; Jie Zhang
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2003-12-29
Filing date: 2004-12-29
Publication date: 2005-09-09
Also published as: CN1635726A

Abstract

A system for implementing data service prepayment in the network. The system includes voice network and data network, and the voice network includes the service control point (SCP) used for storing the information of user account number and executing fee deducting operation, then the data network includes PDSN and AAA. In this system, the SCP is connected with the AAA via a signaling transmission link, and assigns some fee from the corresponding user account number after receiving the accounting request from the AAA, then returns the fee assigned back to the AAA. The AAA controls the data service of the PDSN access users according to the accounting response from the SCP. There is also a method for implementing data service prepayment in the network.

Description

System and method for realizing data service prepayment in code division multiple access network

The present invention relates to data service prepayment of a mobile communication system, and particularly to a system and method for implementing data service prepayment in a code division multiple access (CDMA) network. Background of the invention

In the CDMA network, in addition to the traditional voice services, data services are also rapidly developing, and their status and role are becoming more and more important. In the existing CDMA network, it can be divided into a voice network and a data network according to different service characteristics. The data network is also called a packet network. The CDMA core switching network uses different devices for the voice network and the data network, in which voice service signaling is transmitted through the No. 7 signaling network, and data service signaling is transmitted through the Internet Protocol (IP) network. Since the No. 7 signaling network and the IP network are two relatively independent networks, the payment of voice services and the payment of data services are also relatively independent.

Figure 1 shows a basic structure of an existing CDMA 2000 network. As shown in FIG. 1, a mobile station (MS) is connected to a wireless network (RN), where the RN includes a base station controller (BSC), a base transceiver station (BTS), and a packet control function (PCF) module. The BSC / BTS is connected to a mobile switching center (MSC) for controlling the user's voice service. The MSC is connected to the home location register (HLR) and the intelligent network service control point (SCP) through the SS7 network, and passes The Wireless Intelligent Network (WIN) protocol interacts with the SCP to implement authentication and charging of pre-paid user accounts.

At present, the voice network can provide users with prepayment, that is, the user can first purchase a phone card including a certain amount to establish an account, and then before each call, the voice network authenticates the user and determines that the user is prepaid. After paying a service user and the user ’s phone card has sufficient balance, the user ’s phone access is allowed, and according to the user ’s The voice call time is deducted from the user account in real time. The operations of account creation, authentication, and deduction here are all completed in SCP.

For data services, the MS accesses the packet data service node (PDSN) through the PCF module in the RN. The PDSN is an access gateway that provides services for the MS to access the Internet through IP access. It is specifically responsible for managing user status, Forward user data and assign an IP address to the MS. The PDSN is connected to the home authentication, authorization, and accounting server (AAA) through the IP network. AAA is used to complete the authentication, authorization, and accounting functions of the user account. For data services of PDSN and AAA, communication operators also hope to provide prepaid services, which can guarantee the charging of data services and thus guarantee the operating income of communication operators. However, at present, there is no standard or solution for the prepayment of data services for CDMA 2000. How to provide prepayment for data services for wireless users by communication operators has become an urgent problem. Summary of the invention

In view of this, an object of the present invention is to provide a system for prepaid data services in a CDMA network, so that a communication operator can provide a prepaid service to a data service user, thereby ensuring the data service operation income of the communication operator.

Another object of the present invention is to provide a method for implementing prepayment of data services in a CDMA network, so that a communication operator can provide a prepayment service to a data service user, thereby guaranteeing the data service operation income of the communication operator.

A system for implementing prepayment of data services in a CDMA network according to the present invention includes two parts, a voice network and a data network, and the voice network includes a service control point SCP for storing user account information and performing a chargeback operation, the data network Including the PDSN and AAA, and the SCP is connected to the AAA through a signaling transmission link, and receives After the AAA charging request, a certain fee is allocated from the corresponding user account, and the allocated fee is returned to the AAA. The AAA is further used to control the data service of the PDSN access user according to the fee from the SCP.

The method for implementing data service prepayment in a CDMA network according to the present invention includes at least:

a. Establish a signaling transmission link between the SCP of the voice network and the AAA of the data network in advance;

b. After receiving the data service request from the mobile terminal, the PDSN sends an access request to AAA. After determining that the mobile terminal user is a prepaid user of the data service, the AAA sends an authentication to the SGP through the signaling transmission link. Claim

c SCP allocates a fee from the user's account after successfully authenticating the mobile terminal, and then returns the allocated fee to AAA through the signaling transmission link;

d. AAA instruction PDSN allows mobile terminals to access, and controls mobile terminals to use data services according to the cost allocated by SCP.

As can be seen from the above technical solution of the present invention, the present invention establishes a signaling transmission link between the voice network SCP of the existing mobile communication system and the AAA of the data network, thereby establishing The data network user can use his voice network pre-paid account to pre-pay his own data service, thereby implementing a pre-paid solution for the data service user, ensuring the operating income of the communication operator, and promoting communication. The enthusiasm of operators to develop data services has greatly accelerated the popularity and development of mobile communication data services.

The data service pre-paid user can use his voice network pre-paid account to pre-pay his own data service, so he does not need to register and set up separate accounts for the data service and voice service, thereby greatly improving the data service user's use of data services Convenience.

The invention proposes to charge according to the time, charge according to the flow rate and charge according to the length of the flow. Three methods allow communication operators to flexibly provide data services, and users of data services can flexibly choose a charging method according to their own circumstances, thereby facilitating communication operators and users at the same time.

In the present invention, when a user requests to use a data service, the SCP first allocates a certain amount from the user account, and then the user uses the data service within the limit of the allocated amount. When the amount corresponding to the data service used by the user is close to the limit of the allocated amount, the SCP is requested again to allocate a certain amount, and so on. If at some time when the SCP is requested to allocate a certain amount, the SCP finds that there is not enough balance in the user's account, and the user is stopped from using the data service. Of course, if there is not enough balance in the user account when the amount is allocated for the first time, the user is directly rejected from using the data service. Therefore, the present invention realizes complete real-time deduction, successfully protects the interests of the data service provider, and provides a more sufficient guarantee for the development of the data service. At the same time, if the user actively stops the use of a certain data service, the present invention can return the unused part of the allocated amount to the user account, which fully protects the user's interests from being lost. Brief description of the drawings

Figure 1 shows the basic structure of a CDMA 2000 network in the prior art.

Fig. 2 is a basic structure of a first embodiment of a system for realizing data service prepayment in a CDMA network according to the present invention.

Fig. 3 is a message flow chart of charging according to the first embodiment according to the first embodiment, in which the suspension of the data service is caused by the insufficient account balance of the user.

Fig. 4 is a message flow chart of charging according to the duration according to the first embodiment, wherein the stop of the data service is caused by the user actively terminating the use of the data service.

Fig. 5 is a flow chart of a flow metering message according to the first embodiment, in which the suspension of the data service is caused by the insufficient account balance of the user.

FIG. 6 is a message flow chart of charging according to a flow rate according to a first embodiment, in which a data service The suspension was caused by the user's voluntary termination of the use of data services.

FIG. 7 is a message flow chart of flow-rate-based charging according to the first embodiment, in which the suspension of data services is caused due to insufficient user account balance.

FIG. 8 is a message flow chart of charging according to duration according to the first embodiment, in which the stop of the data service is caused by the user actively terminating the use of the data service.

Figure 9 is the processing flow when dormant handover across PDSN and hard handover between PDSNs that do not support fast handover.

Fig. 10 is a basic structure of a second embodiment of a system for realizing prepayment of data services in a CDMA network according to the present invention. Mode of Carrying Out the Invention

The present invention is described in detail below with reference to the drawings and specific embodiments.

In order to enable the information of the voice prepaid account to be transmitted to the data service network, the present invention first establishes a connection between the network device of the voice network and the network device of the data network, that is, a signaling transmission link capable of message interaction is established. And newly defined a set of message structures that interact between network devices in the voice network and network devices in the data network. The system structure of the first embodiment of the system. It can be seen that, compared with FIG. 1, the present invention establishes a connection between the SCP of the voice network and the AAA of the packet network, that is, a signaling transmission link is established. The present invention draws on the existing TCP / IP protocol and extends it, and uses the extended TCP / IP protocol as the protocol used for the connection. Preferably, the TCP / IP protocol is extended by extending the RADIUS protocol. At the same time, in order to provide prepayment for data services using a voice prepaid user account, the present invention also needs to modify the existing SCP, AAA and PDSN, and modify the signaling between PDSN and AAA accordingly. The following will detail the new signaling transmission link of the present invention and the modification of existing network equipment and protocols. Detailed explanation.

On the basis of the original function, the PDSN according to the present invention further adds the following functions: reporting to the AAA whether the prepaid service is supported in an Access Request message; managing and maintaining triggers configured for each user, and When a trigger condition is met, an accounting request message (Accounting Request) is sent to the AAA; according to the AAA request, a session is terminated and the resource usage is reported, so that the AAA completes the accounting.

The AAA according to the present invention further adds the following functions on the basis of the original functions: storing charging policies and user configuration data for pre-paid services; applying a part of the fee to the SCP for pre-paid users; determining that the users can be maintained according to the charging policies According to the requirements of the communication operator or other reasons, such as handoff, actively send a message to the PDSN to terminate a session on the PDSN; store the IP address of the PDSN and according to the IP address Change to determine if a sleep state has occurred.

Based on the existing functions of the SCP according to the present invention, the following functions are further added: storing the user account information of the data service pre-paid user; verifying whether the data service pre-paid user account is in a valid state; according to a predetermined fee allocation policy Allocate a fee for AAA; process the fee returned by AAA to the SCP; deduct real-time user account usage fees for data services in real time.

In order to support the prepayment of data services, the PDSN needs to report to the AAA whether the prepayment service is supported in the access request message Access Request sent to the AAA. After receiving the access request message from the PDSN, the AAA determines whether the user is a prepaid user according to the user configuration data of the user, and if so, notifies the PDSN in an access request acceptance message (Access Accept) sent to the PDSN Whether the user needs a prepaid service feature is achieved by adding a field shown in Table 1 to the message. Access Request Access Accept Access Reject propertyType value description

Message message message prepaid feature

Pre-Paid-Enabled 26/100 0 0-1 0

Activation flag The attribute Pre-Paid-Enabled shown in Table 1 is used when the AAA notifies the PDSN whether the user needs to activate the prepaid service feature. This attribute value can appear in the Access Accept message. If this attribute is not included, the PDSN does not activate the prepaid feature.

The type of the attribute Pre-Paid-Enabled is 26/100, the length is 4 bytes, and the values can be 0 and 1, where 0 represents that the pre-paid feature is not activated and 1 represents that the pre-paid feature is activated.

The extended attributes of the Accounting Request message (Accounting Request) sent by the PDSN to the AAA and the Accounting Request response message (Accounting Response) returned by the AAA to the PDSN are shown in Table 2.

Table 2

Accounting Accounting Accounting

Accounting

Request Request Request

Property Type Value Description Response

(start) (Interim-Update) (stop)

Message message message

Remanent- Users can maintain the flow

26/101 0 0 0 0-1

Volume s.

Session- user allowed

Time- 26/102 Session Activation 0 0 0 0-1

Remaining minutes

The next time

Tari f- rate switching time

Switch- 26/103 0 0 0 0-1

With the current moment

Duration

Time interval (S)

Trigger- Interim-Update

26/104 0 1 0 0 Type Hair type

Session- Whether the current session

26/105 0 0 0 0-1 Cont End In the above extended attributes, the length of the Remanent-Volume is 4 bytes, which is used to control the number of bytes that can be forwarded by the current connection, which specifically indicates how many kilobytes can be forwarded by the connection. , Including two directions of receiving and sending. Without this parameter, the PDSN will not disconnect the connection because it uses too much traffic. This parameter appears in the Accounting Request Response message (Accounting Response).

Session-Time-Remaining is 6 bytes in length and is used by AAA to control the duration that the PDSN can maintain the session activation status within the current segment reservation fee, which specifically indicates that the connection is in session activation within the current segment reservation fee. How long the state can be maintained. If this parameter does not appear, the PDSN will not disconnect the connection because it is used for too long. This parameter appears in the Accounting Request Response message (Accounting Response). In addition, it should be noted that this parameter is different from the standard RADIUS parameter Session-Timeout, which indicates that the PPP session state can be maintained within the current segment reservation fee. These two parameters exist because the channel connection of CDMA 2000 has two states: PPP session state and session activation state. The rates in these two states are different, so AAA needs to make corresponding budgets based on different rates. .

The length of the Tariff-Switch-Duration is 4 bytes. It is used by the AAA to notify the PDSN device of the rate switching point, and specifically indicates the time interval at which the rate switching is to be performed. The time interval is counted from the last time the connection sent a charging request message for this connection. If this parameter does not appear, the PDS does not consider it necessary to perform rate switching.

The Trigger-Type is 4 bytes in length and is used to indicate the trigger type for reporting an Accounting Request (Interim-Update) message. There are currently four types of triggers, with a value of 1 for the charging cycle trigger, a value of 2 for the rate switching trigger, and a value of 3 for the session trigger. Live trigger; value 4 means traffic trigger. The charging cycle trigger is used to report AAA when the charging cycle is reached, which is applicable to all charging methods. The rate switching trigger is used to report AAA when the rate switching point is reached, which is applicable to all charging methods. The session activation trigger is used to The segmentation reservation fee can be maintained for AAA during the duration of the session activation. It is suitable for charging according to the duration. The traffic trigger is used to segment the reservation fee and can be reported to the AAA after the available traffic is exhausted within the maintenance period. Charged by traffic. As for the charging method, the present invention will be described in detail later.

Session-Cont is 6 bytes in length and is used to indicate whether the session continues. This attribute appears in Accounting Response. If the value of this attribute is 0, which indicates that the session is terminated, the PDSN immediately reports an Accounting Request (Stop) to the AAA, and terminates the session. If the value of this attribute is 1 indicating that the session is continued, or the attribute does not appear in the Accounting Response, the PDSN does not terminate the session, so that the session continues.

The above describes the modification of the signaling between the PDSN and the AAA, and the following describes the signaling interaction between the AAA and the SCP, so as to realize the cooperative work of the AAA and the SCP, and complete the prepayment of the data service.

In the prior art, there is no signaling protocol between AAA and SCP. Therefore, the present invention extends the existing RADIUS protocol, that is, newly defines a message structure for interaction between AAA and SCP. The message structure includes a message header and a message body. The structure of the message header is shown in Table 3. It includes the command length and command identifier.

table 3

As shown in Table 4, there are four types of commands: an authentication request message, an authentication request response message, an accounting request message, and an accounting request response message, and their command identifiers are 1, 2, 3, and 4, respectively. Table 4

Command- ID value

Auth-Request 1 message

Auth-Response 2 authentication request response message

Accounting-Request 3

Accounting-Response 4 Charge Request Response Message The following describes the message body structure of each command. Authentication request message

The Authentication Request is sent by the AAA to the SCP to request authentication and apply for fees. The extended attributes are shown in Table 5.

table 5

The Authentication Response message is returned by the SCP to the AAA, indicating that the access is accepted or rejected. If accepted, the session fee will be allocated at the same time. Its extended attributes are shown in Table 6. Table 6

In Table 6 above, there are six types of authentication responses. If the value is 0, the authentication is passed; the value is 1, the user data does not exist; the value is 2, the stored value card is invalid; the value is 3, the user account balance is not greater than Zero; a value of 4 indicates that the user has been blocked; a value of 5 indicates a system error.

Accounting Request Message The Accounting Request is actively sent by the AAA to the SCP, requesting real-time deduction of the balance from the user account. The extended attributes are shown in Table 7.

Table 7

Field Type Value Bytes Property Description Type

SessionID 26/121 4 INTEGER Session ID required (extension)

MSISDN 26/122 up to 21 CHAR mobile terminal number required

Code (existing)

AAA-Address 26/123 up to 15 CHAR AAA server optional

IP address (existing)

AAA-ID 26/124 4 INTEGER AAA server optional

Numbering OperationType 26/127 4 INTEGER Operation type; 1 required

Indicate the fee application (extension) Please message, Form 2

Show fee refund

News

FeeApply 26/128 4 INTEGER Required for OperationType- 1

(extension)

FeeLeft 26/129 4 INTEGER Remaining fee Operation type- 1 optional

(extension)

FeeReturn 26/130 4 INTEGER Optional fee refund type OperationType = 2

(extension) The Accounting Response Request message is returned by the SCP to the AAA. Its extended attributes are shown in Table 8.

Table 8

Field Type Value Bytes Property Description Type

SessionID 26/121 4 INTEGER Session ID required (extension)

MSISDN 26/122 up to 21 CHAR mobile terminal number required

Code (extension)

AAA-Address 26/123 up to 15 CHAR AAA server optional

IP address (extension)

AAA-ID 26/124 4 INTEGER AAA server optional

Number (extension)

OperationType 26/127 4 INTEGER Operation type; 1 required

Indicates an extension request response message.

2 means cost return

Also confirm message

FeeApplied 26/128 4 INTEGER Operation Type = l

In the present invention, there are three charging methods, which are charging according to the duration, charging according to the flow rate, and charging according to the length / flow rate. Among them, charging according to the duration means that a certain amount of money is converted into a certain length of time each time. The user can use the data service within this time length. If the time length is exceeded, the data service is stopped to be provided to the user or the cost is redistributed. According to the flow metering, a certain amount of money is converted into a certain number of traffic each time. The user can use the data service within the amount of the traffic amount. If the traffic amount is exceeded, the data service is stopped to be provided to the user or the cost is redistributed. The duration / flow rate charging is a combination of the above two methods, that is, a certain amount is converted into a certain length of time and a certain number of traffic according to a preset policy. Once the user uses the data service to reach the time length and One of the traffic numbers, stop providing data services to users or reallocating expenses. The third method, that is, according to the duration / flow metering method, can prevent users from accessing the data service network for a long time without data transmission, and also prevents users from transmitting a large amount of data in a short time, thereby avoiding The disadvantages of the first two methods more effectively ensure the interests of communication operators.

The following describes the processing flow of the present invention with respect to these three charging modes, respectively. Figure 3 shows the flow chart of charging by duration.

In step 301, the mobile user requests to access the packet network, and the PDSN sends an access request message (Access Request) to the AAA after receiving the request from the mobile user. The PDSN includes information indicating whether the PDSN supports prepaid services.

In step 302, after receiving the access request message from the PDSN, the AAA determines whether the PDSN supports prepayment according to the information carried in the message indicating whether the PDSN supports prepaid services. If so, the AAA according to the user information saved by itself Determine whether the caller is a pre-paid user. If the caller is a pre-paid user, AAA sends an SCP to the voice network. Send an authentication request message (Authentication Request), which includes FeeApply, an application fee parameter, to request the SCP to allocate a fee, and the SessionID parameter here is 1. If the AAA judges that the PDSN does not support prepaid or the caller is not a prepaid user, it performs processing according to the processing flow of the existing packet network, that is, instructs the PDSN not to allow access to the mobile terminal.

In step 303, the SCP passes the user authentication, and then allocates a fee to the user according to the application fee parameters in the authentication request message and the remaining cost in the user account saved by itself, and then returns an authentication request response message (Authentication Response) to the AAA. , Which includes the FeeApplied parameter representing the cost information assigned to the user.

In step 304, the AAA returns an access request response message (Access Response) to the PDSN, indicating that the PDSN allows the user to access.

In step 305, the PDSN reports an initial accounting request message (Accounting Request (start)) to the AAA after receiving a message from the AAA that allows the user to access.

In step 306, the AAA determines the current charging policy according to the charging policy parameters. The billing strategy here is one of billing by duration, billing by flow rate, and billing by length. The specific selection of the charging strategy is set in the AAA by the communication operator through parameters in advance. In this embodiment, the charging is set according to the duration. Then, AAA calculates the duration of the active session according to the cost allocated by the SCP, fills in the Session-Time-Remaining parameter in the Accounting Request response message, and sets the Session-Cont to 1. Then send a charging request response message to the PDSN. The PDSN accesses the user after receiving the message. The PPP negotiation succeeds, the session is established, and the PDSN starts a time counter.

In step 307, when the timing of the PDSN reaches the duration in the Session-Time-Remaining parameter, the PDSN sends an Accounting Request (Interim-Update) message to AAA, where the trigger type is 3.

In step 308, the AAA confirms that the user's current segmentation fee has been used up, and sends it to the SCP. Accounting Request, where the operation type parameter (Operation Type) is 1, indicating a fee application, the message includes the FeeApply parameter, and the SessionID parameter indicates 2 in the second session.

In step 309, the SCP allocates a fee to the user based on the FeeApply parameter in the Accounting Request and the remaining cost in the user account it has saved, and returns an Accounting Response to the AAA, where the Operation Type parameter (Operation Type) is 1, which indicates the fee application In response, the message includes a FeeApplied parameter indicating the cost information allocated for the user.

In step 310, the AAA calculates the activation session maintainable time according to the cost allocated by the SCP, fills in the Session-Time-Remaining parameter in the Accounting Response, sets the Session-Cont to 1, and then sends a charging request response message to the PDSN. Then, the PDSN restarts timing and provides data services to the user.

Then, the operations of steps 307 to 310 are repeated until the user actively stops the data service or the PDSN stops the user's session because the user's account balance is insufficient. Because the processing procedures of these two methods are different, they are described separately below.

When the user actively stops the data service, as shown in FIG. 3, in step 320, the PDSN reports the Accounting Request (Stop) message to the AAA after receiving the information that the user stopped the data service, which includes the Acct-Session-Time parameter, indicating that Duration of using data services in the current time period. Since this parameter is a parameter that already exists in the prior art, this parameter is not listed in Table 2.

In step 321, the AAA learns the duration of the active session according to the Acct-Session-Time parameter, so as to calculate the user's used fee and unused fee in this segment. AAA determines whether the unused fee is zero. If so, end this process, otherwise send an Accounting Request to the SCP, where the Operation Type parameter is 2, which means the fee is refunded. The message includes the FeeReturn parameter, which indicates the fee returned. That is, unused by the user in this section Cost.

In step 322, the SCP adds the refunded fee to the user account according to the FeeReturn parameter, and then returns an Accounting Response to AAA, where Operation Type is 2, which indicates the fee refund confirmation.

In step 323, the AAA sends an accounting request response message Accounting Response to the PDSN, where the Session-Cont is 0, that is, instructs the PDSN to end the session.

The PDSN terminates the session after receiving an Accounting Response with a Session-Cont of 0. So far, the processing flow ends.

In the case where the user's session is switched by the PDSN because the user account balance is insufficient, the processing flow is shown in Figure 4.

In step 420, when the timing of the PDSN reaches the duration in the Session-Time-Remaining parameter, the PDSN sends an Accounting Request (Interim-Update) message to AAA, where the trigger type is 3.

In step 421, the AAA confirms that the user's current segmentation fee has been used up, and sends an Accounting Request to the SCP, where the Operation Type parameter (Operation Type) is 1, indicating a fee application, and the message includes the FeeApply parameter.

In step 422, the SCP determines that the remaining fee is insufficient to allocate a fee to the user according to the FeeApply parameter in the Accounting Request and the remaining fee in the user account saved by it, and returns an Accounting Response to the AAA, where the Operation Type parameter (Operation Type) A value of 1 indicates a fee application response, and the value of the FeeApplied parameter in the message is 0.

In step 423, the AAA sets the Session-Time-Remaining parameter to 0 and the Session-Cont parameter to 0 according to the cost allocated by the SCP, and then sends a charging request response message to the PDSN.

The PDS terminates this upon receiving an Accounting Response with a Session-Cont of 0 Sessions. So far, the processing flow ends.

The above process is a basic process of the present invention. In addition to the session activation trigger, the charging request message reported by the PDSN to the AAA can also trigger a charging cycle trigger and a rate switching trigger.

When the timing of the PDSN reaches the predetermined charging period, the charging period trigger is triggered, and the PDSN sends an Accounting Request (Interim-Update) message to the AAA, where the trigger type is 1 and includes the Acct-Session-Time parameter.

AAA obtains the active session duration according to the Acct-Session-Time parameter, and then determines the user's used expenses in this segment, and subtracts the used expenses from the current segment expenses to obtain the unused expenses. If the unused fee is 0, AAA applies a fee to the SCP in a similar manner to step 308, and then calculates the value of the Session-Time-Remaining parameter for the newly applied fee. If the unused fee is not 0, AAA recalculates the value of the Session-Time-Remaining parameter based on the unused fee. Then AAA re-determines the Tariff-Switch-Duration parameters and includes the new Session-Time-Remaining parameters and Tariff-Switch-Duration parameters in the charging request response message and returns it to the PDSN.

After receiving the charging request response message from AAA, the PDSN resets the session activation trigger and rate switching trigger according to the Session-Time-Remaining parameter and Tariff-Switch-Duration parameter.

In the process of using the data service by the user, it is possible to reach the rate switching time, for example, at 12 pm, the rate starts at half price. At this time, the rate switching trigger is triggered, and the PDSN sends an Accounting Request (Interim-Update) message to the AAA, where the trigger type is 2, and the Acct-Session-Time parameter is included.

According to the Acct-Session-Time parameter, AAA obtains the user's used expenses in this segment, and subtracts the used expenses from the current segment expenses to obtain the unused expenses. If the unused fee is 0, the AAA applies a fee to the SCP in a similar manner to step 308, and then applies the new application fee according to Calculate the value of the Session-Time-Remaining parameter at the new rate. If the unused fee is not 0, AAA recalculates the value of the Session-Time-Remaining parameter at the new rate based on the unused fee. Then AAA re-determines the Tariff-Switch-Duration parameter, and includes the new Session-Time-Remaining parameter and Tariff-Switch-Duration parameter in the charging request response message and returns it to the PDSN.

The processing flow of charging according to the duration method is described above with reference to FIG. 3 and FIG. 4, and the processing flow of charging according to the flow method is described below with reference to FIGS. 5 and 6.

As shown in FIG. 5, steps 501 to 505 are the same as steps 301 to 305 in FIG. 3, and details are not described herein again.

In step 506, the AAA determines the current charging policy according to the charging policy parameters. The billing strategy here is one of billing by duration, billing by flow rate, and billing by length. The specific selection of the charging strategy is set in the AAA by the communication operator through parameters in advance. In this embodiment, the setting is charged according to the flow rate. AAA calculates the traffic that can be maintained according to the cost allocated by the SCP, fills in the Remanent- Volume parameter in the Accounting Request response message, sets the Session-Cont to 1, and then sends the Accounting Request Response message to the PDSN. After receiving the message, the PDSN accesses the user, the PPP negotiation succeeds, the session is established, and the PDSN starts a traffic counter.

In step 507, when the PDSN's traffic trigger is triggered, the PDSN sends an Accounting Request (Interim-Update) message to the AAA, where the trigger type is 4.

In step 508, the AAA confirms that the user's current segmentation fee has been used up, and sends an Accounting Request to the SCP, where the Operation Type parameter (Operation Type) is 1, which indicates the fee application, and the message includes the FeeApply parameter. In step 509, the SCP allocates a fee to the user according to the FeeApply parameter in the Accounting Request and the remaining cost in the user account it has saved, and returns an Accounting Response to the AAA, where the Operation Type parameter (Operation Type) is 1, indicating the fee application In response, the message includes a Fee Applied parameter indicating the cost information allocated for the user.

In step 510, the AAA calculates the maintainable traffic according to the cost allocated by the SCP, fills in the Remanent- Volume parameter in the Accounting Response, sets the Session-Cont to 1, and then sends the accounting request response message to the PDSN. The PDSN then resumes counting traffic and provides users with data services.

Then, the operations of steps 507 to 510 are repeated until the user actively stops the data service or the processing flow is different, which will be described separately below.

As shown in FIG. 5, in step 520, the PDSN reports the Accounting Request (stop) message to the AAA after receiving the information that the user stopped the data service, which contains the Acct-Input-Octets parameter representing the input traffic and the Acct- Output-Octets parameter. Since these two parameters are already existing in the prior art, they are not listed in Table 2.

In step 521, the AAA learns the used traffic according to the above two parameters, and thereby calculates the used fee and the unused fee of the user in this segment.

In step 522, the SCP adds the refunded fee to the user account according to the FeeReturn parameter, and then returns an Accounting Response to the AAA, where the Operation Type is 2, which indicates the fee refund confirmation.

In step 523, the AAA sends an accounting request response message Accounting Response to the PDSN, where the Session-Cont is 0, that is, instructs the PDSN to end the session.

In the case that the user's session is switched by the PDSN because the user account balance is insufficient, the processing flow is shown in FIG. 6.

In step 620, when the PDSN detects that the traffic is exhausted, the traffic trigger is triggered, and the PDSN sends an Accounting Request (Interim-Update) message to the AAA, where the trigger type is 4.

In step 621, the AAA confirms that the user's current segmentation fee has been used up, and sends an Accounting Request to the SCP, where the Operation Type parameter (Operation Type) is 1, indicating a fee application, and the message includes the FeeApply parameter.

In step 622, the SCP determines that the remaining fee is insufficient to allocate a fee to the user based on the FeeApply parameter in the Accounting Request and the remaining fee in the user account it saved, and returns an Accounting Response to the AAA, where the operation type parameter (Operation Type) is 1, indicating a fee application response, and the value of the FeeApplied parameter in the message is 0.

In step 623, the AAA sets the Remanent-Volume parameter to 0 and the Session-Cont parameter to 0 according to the cost allocated by the SCP, and then sends a charging request response message to the PDSN.

Similarly, similar to the use-time charging method, when the PDSN timing reaches a predetermined charging period, a charging trigger is triggered, and the PDSN sends an Accounting equest (Interim-Update) message to AAA, where the trigger type is 1 and includes Acct-Inp t-Octets parameter and Acct-Output-Octets parameter.

AAA determines the user's used fees in this segment according to the above two parameters, and subtracts the used fees from the current segment fees to obtain unused fees. If the unused fee is 0, AAA follow 508 Requests a fee from the SCP in a similar manner, and then calculates the value of the Remanent-Volume parameter for the newly applied fee. If the unused cost is not 0, AAA recalculates the value of the Constant-Volume parameter based on the unused cost. Then the AAA re-determines the Tariff-Switch-Duration parameters, and includes the new Romantic-Volume parameters and Tariff-Switch-Duration parameters in the charging request response message and returns it to the PDSN.

After receiving the accounting request response message from AAA, the PDSN resets the traffic trigger and rate switching trigger according to the Remanent-Volume parameter and Tariff-Switch-Duration parameter.

When the rate switching trigger is triggered, the PDSN sends an Accounting Request (Interim-Update) message to AAA, where the trigger type is 2 and includes the Acct-Input-Octets parameter and the Acct-Output-Octets parameter.

Based on these two parameters, AAA obtains the user's used expenses in this segment, and subtracts the used expenses from the current segment expenses to obtain the unused expenses. If the unused fee is 0, AAA applies a fee to the SCP in a similar manner to step 508, and then calculates the value of the Remanent-Volume parameter for the newly applied fee at the new rate. If the unused fee is not 0, AAA recalculates the value of the Remanent-Volume parameter based on the unused fee at the new rate. Then AAA re-determines the Tariff-Switch-Dumtion parameters, and includes the new Remanent-Volume parameters and Tariff-Switch-Duration parameters in the charging request response message and returns it to the PDSN.

After receiving the charging request response message from AAA, the PDSN resets the traffic trigger and the rate switching trigger according to the spring-volume number and the Tariff-Switch-Duration parameter.

Next, referring to FIG. 7 and FIG. 8, a description will be given of a processing flow according to a time-based traffic charge method. As shown in FIG. 7, steps 701 to 705 are completely the same as steps 301 to 305 in FIG. 3, and are not repeated here.

In step 706, the AAA determines the current charging policy according to the charging policy parameters. Here's the plan The charging strategy is one of charging by duration, charging by flow rate, and charging by length flow rate. The specific selection of the charging strategy is set in the AAA by a parameter in advance by the communication operator. In this embodiment, the flow rate is set according to the duration. The cost allocation AAA SCP assigned a predetermined time and the amount of traffic policy calculates the estimated cost of the flow rate and duration, and then calculates the time based on time can maintain flow rates and flow rates can be maintained and, to fill the other points ¹ J Set the Session-Cont to 1 in the Session-Time-Remaining parameter and the Remanent- Volume parameter in the Accounting Request Response message (Accounting Response), and then send the Accounting Request Response message to the PDSN. After receiving the message, the PDSN accesses the user, the PPP negotiation succeeds, the session is established, and the PDSN starts a timer and a traffic counter.

In step 707, when the timing of the PDSN reaches the duration in the Session-Time-Remaining parameter, the PDSN sends an Accounting Request (Interim-Update) message to the AAA, which includes the Acct-Session-Time parameter, the Acct-Input-Octets parameter, and the Acct -Output-Octets parameter, and trigger type is 3.

In step 708, the AAA calculates the currently used segmentation fee according to the above three parameters of the Accounting Request (Interim-Update) message, and determines whether the user's current segmentation fee is lower than a predetermined cabinet value, and if it is greater than or equal to the alarm value, directly execute Step 710 (not shown in the figure). If it is less than the threshold, the AAA sends an Accounting Request to the SCP, where the Operation Type parameter (Operation Type) is 1, indicating a fee application, and the message includes the FeeApply parameter.

In step 709, the SCP allocates a fee to the user according to the FeeApply parameter in the Accounting Request and the remaining cost in the user account it has saved, and returns an Accounting Response to the AAA, where the Operation Type parameter (Operation Type) is 1, which indicates the fee application In response, the message includes a FeeApplied parameter indicating the cost information allocated for the user. In step 710, the AAA calculates a budget cost for the duration and the traffic according to the cost allocated by the SCP or the user's current segmentation cost and a predetermined time traffic amount allocation strategy, and then calculates the maintainable time according to the time rate and the traffic rate, respectively. And maintainable traffic, fill in the Session-Time-Remaining parameter and the Remanent-Volume parameter in the Accounting Response, set the Session-Cont to 1, and then send the charging request response message to the PDSN. Then PDSN restarts to calculate time and traffic, and provides users with data services.

Then, the operations of steps 707 to 710 are repeated until the user actively stops the data service or the PDSN stops the user's session because the user's account balance is insufficient.

The above step 707 shows the case where it is executed due to the trigger of the session activation trigger. For the triggering of the traffic trigger, except that the trigger type in the Accounting Request (Interim-Update) message is 4, the rest of the processing is exactly the same, so it will not be described again.

The following also describes the processing flow when the user actively stops the data service with reference to FIG. 7.

As shown in FIG. 7, in step 720, the PDSN reports the Accounting Request (stop) message to the AAA after receiving the information that the user stopped the data service, which includes the Acct-Session-Time parameter, the Acct-Input-Octets parameter, and the Acct-Output -Octets parameter.

In step 721, the AAA learns the used time and used traffic according to the above three parameters, so as to calculate the user's used fee and unused fee in this segment.

In step 722, the SCP adds the refunded fee to the user account according to the FeeReturn parameter, and then returns an Accounting Response to the AAA, where Operation Type is 2, which indicates the fee refund confirmation.

In step 723, the AAA sends an accounting request response message Accounting Response to the PDSN, where the Session-Cont is 0, that is, instructs the PDSN to end the session.

The PDSN terminates the session after receiving an Accounting Response with a Session-Cont of 0. So far, the processing flow ends. In the case where the user's session is switched by the PDSN because the user account balance is insufficient, the processing flow is shown in FIG. 8.

In step 820, when the PDSN detects the duration or the traffic is exhausted, the duration trigger or the traffic trigger is triggered, and the PDSN sends an Accounting Request (Interim-Update) message to the AAA, where the trigger type is 3 or 4.

In step 821, the AAA confirms that the user's current segmentation fee has fallen below a predetermined threshold, and sends an Accounting Request to the SCP, where the Operation Type parameter is 1 to indicate a fee application, and the message includes the FeeApply parameter.

In step 822, the SCP determines that the remaining fee is insufficient to allocate a fee to the user based on the FeeApply parameter in the Accounting Request and the remaining fee in the user account it has saved, and returns an Accounting Response to the AAA, where the Operation Type parameter (Operation Type) is 1, indicating a fee application response, and the value of the FeeApplied parameter in the message is 0.

At step 823, the AAA sets the Session-Time-Remaining parameter and the Remanent-Volume parameter to 0, sets the Session-Cont parameter to 0, and sends a charging request response message to the PDSN according to the cost allocated by the SCP. .

Similarly, similar to the duration charging method, when the PDSN timing reaches a predetermined charging period, a charging trigger is triggered, and the PDSN sends an Accounting Request (Interim-Update) message to AAA, where the trigger type is 1 and includes Acct-Session-Time parameters, Acct-Input-Octets parameters, and Acct-Output-Octets parameters.

AAA determines the user's used fees in this segment according to the above three parameters, and subtracts the used fees from the current segment fees to obtain unused fees. If the unused fee is 0, AAA follows and steps 708 applies a fee to the SCP in a similar manner, and then calculates the value of the Session-Time-Remaining parameter and the Remanent- Volume parameter for the newly applied fee. If the unused cost is not 0, AAA recalculates the values of the Session-Time-Remaining parameter and the Remanent- Volume parameter based on the unused cost. Then AAA re-determines the Tariff-Switch-Duration parameters and includes the new. Remanent- Volume parameters and Tariff-Switch-Duration parameters in the charging request response message and returns it to the PDSN.

After receiving the accounting request response message from AAA, the PDSN resets the session activation trigger, traffic trigger, and rate switching trigger according to the Session-Time-Remaining parameter, Remanent- Volume parameter, and Tariff-Switch-Duration parameter.

When the rate switching trigger is triggered, the PDSN sends an Accounting Request (Interim-Update) message to AAA, where the trigger type is 2 and includes the Acct-Session-Time parameter, the Acct-Input-Octets parameter, and the Acct-Output-Octets parameter.

Based on these three parameters, AAA obtains the user's used expenses in this segment, and subtracts the used expenses from the current segment expenses to obtain the unused expenses. If the unused fee is 0, AAA applies a fee to the SCP in a similar manner to step 708, and then calculates the value of the Session-Time-Remaining parameter and the Remanent- Volume parameter for the newly applied fee at the new rate. If the unused fee is not 0, AAA recalculates the values of the Session-Time-Remaining parameter and the Remanent- Volume parameter based on the unused fee at the new rate. Then AAA re-determines the Tariff-Switch-Duration parameters and includes the new Session-Time-Remaining parameters, Remanent- Volume parameters and Tariff-Switch-Duration parameters in the charging request response message and returns it to the PDSN.

After receiving the accounting request response message from AAA, the PDSN uses the Session-Time-Remaining parameter, Remanent- Volume parameter, and The Tariff-Switch-Duration parameter resets the session activation trigger, traffic trigger, and rate switching trigger.

In an actual application process, the mobile station MS may perform a Simple IP (Simple IP) switch or a Mobile IP (Mobile IP) switch. These two handover methods are similar. The following uses simple IP handover as an example to describe the processing flow.

When the MS switches between different PCFs belonging to the same PDSN, since the PPP session does not need to be renegotiated, the user's balance information on the client can continue to be used.

If the PDSN supports fast handover, when the MS performs a hard handover across the PDSN, a P-P session is established between the target PDSN and the serving PDSN. Since the serving PDSN is the same as the serving PDSN before the handover, there is no need to renegotiate the PPP session, and the user's balance information on the client can continue to be used.

Both the dormant handover across the PDSN and the hard handover between PDSNs that do not support fast handover need to change the serving PDSN, so PPP needs to be renegotiated. If the MS's account balance on the SCP before the handover is not much, and all of it is allocated to the PDSN before the handover, if this part of the balance before the handover uses only a small part of the MS, a sleep handover across the PDSN is performed or is not supported For a hard handover between fast-switching PDSNs, the MS may refuse access due to insufficient SCP account balance when authenticating on the new PDSN. At this time, the home AAA needs to actively request the PDSN before the switch to end the session through the RADIUS extended message SessionControl (Terminate-Request) and report the Accounting Request (Stop). The home AAA returns the fee to the SCP, and the SCP allocates this balance to the switched PDSN. In this process, HA is required to maintain the user's IMSI and the IP address of the accessed PDSN and changes. The specific processing flow is shown in Figure 9.

In step 901, when the MS switches to the target PDSN, authentication is performed in the PPP Link Configuration Protocol (LCP) phase, and the target PDSN sends an access request message Access to the home AAA. Rsqusst.

In step 902, the AAA sends an authentication request message to the SCP. In step 903, the SCP rejects the user's access request because of insufficient user account balance, and sends an authentication request response message to the AAA indicating that the authentication has failed.

In step 904, the AAA sends a Session Control message to the PDSN before the handover, and requests to recover the amount allocated to the MS before the handover.

In step 905, the PDSN before the handover returns the duration balance or traffic balance to the AAA through an Accounting Request (Stop).

In step 906, the AAA converts the duration balance or traffic balance into an account balance, and returns it to the SCP through an Accounting Request fee of operation type 2.

In step 907, the AAA sends an Authentication Request message to the SCP again.,

In step 908, the SCP allocates the amount, and sends the allocated amount to the AAA through a response message indicating that the authentication is successful.

In step 909, the AAA determines the corresponding duration or traffic, and then sends an access request response message to the PDSN, allowing the user to use the data service.

The first embodiment of the present invention has been described above. FIG. 10 shows a system structure of a second embodiment of the CDMA 2000 according to the present invention. It can be seen that, compared with FIG. 2, a data service network further adds a prepaid server (PPS), which is hereinafter referred to as data PPS, and is used for account storage, fee budget, and billing of data service prepaid users. Features. Data PPS and AAA connections in the data network.

In the second embodiment, the interface between the voice network and the data network is not established between the SCP and AAA, but is established between the SCP and the data PPS. In this way, in the first embodiment, all signaling interactions between AAA and SCP need to be forwarded through data PPS. Except that the signaling is forwarded by the data PPS described above, the second embodiment is basically similar to the first embodiment. It will not be described in detail here.

In the second embodiment, the data PPS may be integrated with a business content service gateway (CP GW). In addition, the data PPS can also be integrated into the AAA, so that its basic processing flow is exactly the same as the first embodiment.

In the first and second embodiments, a PPS may be integrated in the SCP of the voice network, which will be referred to as a voice PPS in the following. Operations such as account creation, authentication, and chargeback described in the present invention are all performed in the voice PPS in the SCP. Of course, it can be understood that the voice PPS can also be separately set in the voice network.

The present invention is preferably applicable to a CDMA 2000 network, especially a CDMA 2000 IX network, but the present invention is not limited to this, and the above-mentioned spirit of the present invention can be applied to other mobile communication systems.

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 present invention. Within the scope of protection.

Claims

Claim

1. A system for implementing prepaid data services in a CDMA network, the CDMA network includes a voice network and a data network, and the voice network includes a service control point for storing user account information and performing chargeback operations SCP, the data network includes PDSN and AAA, which is characterized in that the SCP is connected to the AAA through a signaling transmission link, and after receiving a charging request from the AAA, allocates a segment from the corresponding user account The fee, and then return the allocated fee to the AAA, which is further used to control the data service of the PDSN access user according to the fee from the SCP.

2. The system according to claim 1, wherein the transmission link uses a TCP / IP protocol.

3. The system according to claim 2, wherein the TCP / IP protocol is an extended RADIUS protocol, and the signaling transmitted on the transmission link includes an authentication request message, an authentication request response message, Accounting request message and accounting request response message.

4. The system according to claim 3, wherein the authentication request message, the authentication request response message, the charging request message and the charging request response message include at least a session identifier and mobile terminal number information.

5. The system according to claim 4, wherein the authentication request response message further includes allocated cost information and authentication response information indicating an authentication result; and the charging request message further includes operation type information. When the operation type indicates a fee application, further including application fee information, and when the operation type indicates a fee refund, further including the returned cost information; the charging request response message further includes operation type information, and in the operation type Indicating the fee application response further includes the requested fee information.

6. The system according to claim 5, wherein the authentication result is that the authentication is passed, the user data does not exist, the stored value card is invalid, the user account balance is not greater than zero, and the user has One of blocked and system errors.

7. The system according to claim 1, wherein the data network further comprises a data prepaid server PPS, and the SCP is connected to the AAA through a signaling transmission link via the data PPS for connection .

8. The system according to any one of claims 1 to 7, characterized in that the SCP further includes a voice PPS, and the storing and deducting user account information is performed by the voice PPS, and the The SCP is connected to AAA through a signaling transmission link. The voice PPS in the SCP is connected to AAA through a signaling transmission link. The SCP allocates a fee from the corresponding user account after receiving a charging request from AAA. This is done by voice PPS.

9. A method for implementing prepayment of data services in a CDMA network, the CDMA network includes a voice network and a data network, and the voice network includes a service control point SCP for storing user account information and performing a chargeback operation The data network includes PDSN and AAA, and the method at least includes:

b. After receiving the data service request from the mobile terminal, the PDSN sends an access request to AAA. After determining that the mobile terminal user is a prepaid user of the data service, the AAA sends an authentication to the SCP through the signaling transmission link. Claim

10. The method according to claim 9, wherein the establishment of the signaling transmission link between SCP and AAA in step a is to define the consumption of transmission signaling by extending the RADIUS protocol. Information format, the transmission signaling includes an authentication request message, an authentication request response message, a charging request message, and a charging request response message.

11. The method according to claim 10, wherein the authentication request message, the authentication request response message, the charging request message, and the charging request response message include at least a session identifier and mobile terminal number information.

12. The method according to claim 11, wherein the authentication request response message further includes allocated cost information and authentication response information; the charging request message further includes operation type information, and in the operation When the type indicates the fee application, the application fee information is further included, and when the operation type indicates the fee refund, the returned cost information is further included; the charging request response message further includes the operation type information, when the operation type indicates the fee application response It also includes information on the fees requested.

13. The method according to claim 9, characterized in that, step b further comprises: adding an information indicating whether the PDSN supports prepayment to the access request sent by the PDSN to the AAA, and the AAA receives the request Then, it is further determined whether the PDSN supports prepayment, and if so, the step of judging whether the mobile terminal user is a prepaid user of the data service is performed; otherwise, the PDSN is instructed to not allow access to the mobile terminal.

14. The method according to claim 9, characterized in that, in step d, controlling the mobile terminal to use the data service according to the cost allocated by the SCP comprises:

dl. After receiving the message that the mobile terminal is allowed to access, the PDSN reports an initial charging request message to the AAA;

d2, the AAA converts the cost allocated by the SCP into control information used to indicate a condition for stopping providing data services to the mobile terminal according to a predetermined charging policy, and then sends the control information to the PDSN;

d3. The PDSN monitors the state of the mobile terminal using the data service according to the control information received from the AAA, and stops providing the data service to the mobile terminal when the condition is met.

15. The method according to claim 14, characterized in that the control information is a parameter indicating a duration for which an active session can be maintained, the PDSN further includes a session activation trigger, and step d3 includes:

The PDSN's session activation trigger monitors the length of time that the mobile terminal uses the data service, and triggers when the monitored time length is equal to the activation session's sustainable time, and the PDSN stops providing data services to the mobile terminal when it detects the trigger.

16. The method according to claim 14, wherein the control information is a parameter indicating that the traffic can be maintained, the PDSN further includes a traffic trigger, and step d3 includes:

The PDSN's traffic trigger monitors the traffic of the mobile terminal using data services, and triggers when the monitored traffic is equal to the maintainable traffic, and the PDSN stops providing data services to the mobile terminal when it detects the trigger.

17. The method according to claim 14, wherein the control information is a parameter indicating a sustainable time and a sustainable flow parameter of the activation session, and the PDSN further includes a session activation trigger and a traffic trigger, and d3 includes:

The PDSN's session activation trigger monitors the length of time that the mobile terminal uses the data service and triggers when the monitored time length is equal to the duration of the activation session. The traffic trigger monitors the traffic of the mobile terminal using the data service and monitors the The trigger is triggered when the traffic equals the maintainable traffic, and the PDSN stops providing data services to the mobile terminal when any trigger is detected.

18. The method according to any one of claims 15 to 17, characterized in that between the PDSN detecting the triggering and stopping providing data services further comprises:

d41. After receiving the trigger, the PDSN sends an intermediate charging request message to the AAA; d42, the AAA sends a charging request message to the SCP, and the SCP determines whether the user account balance is sufficient. If yes, perform step d43, otherwise perform step d46;

d43, SCP allocates a fee from the user account, and then passes the allocated fee through billing Request response message returned to AAA;

d44. The AAA converts the cost allocated by the SCP into control information according to a predetermined charging policy, and then sends the control information to the PDSN;

d45, the trigger of the PDSN monitors the status of the mobile terminal using the data service according to the control information, and triggers when the condition is reached, and then returns to step d41;

d46. The SCP returns a charging request response message indicating unallocated charges to AAA; d47, AAA sets the control information to zero and sets the control session parameters to zero, and then sends the information to the PDSN through the charging request response message;

d48. After receiving the charging request response message, the PDSN stops providing data services to the mobile terminal.

19. The method according to any one of claims 15 to 17, before the PDSN detects the trigger, further comprising:

After receiving the information that the mobile terminal actively stops the data service, the PDSN reports to the AAA a charging request message indicating the stop, which includes the current status of the mobile terminal using the data service;

AAA determines the remaining cost of the allocated cost according to the current state, and then sends the remaining cost to the SCP through a billing request;

SCP returns the remaining charges to the account of the mobile terminal user, and then returns confirmation information to AAA;

AAA instructs PDSN to stop providing data services to mobile terminals.

20. The method according to any one of claims 15 to 17, wherein the PDSN further comprises a charging cycle trigger, and after the PDSN detects the triggering of the charging cycle trigger, further comprising:

The PDSN sends an intermediate charging request message to the AAA, where the trigger type indicates that the charging cycle trigger is triggered, and the request message includes the current status of the mobile terminal using the data service. State

AAA determines the remaining cost of the allocated fees according to the current state, and determines whether the remaining fees are zero, and if so, sends a billing request message for applying for fees to the SCP, and then determines control information according to the fees allocated by the SCP; Otherwise, the control information is directly determined based on the remaining costs;

The AAA sends control information to the PDSN, and the PDSN resets a charging cycle trigger, a session activation trigger, and / or a traffic trigger according to the control information.

21. The method according to any one of claims 15 to 17, wherein the PDSN further comprises a rate switching trigger, and after the PDSN detects the trigger of the rate switching trigger, further comprising:

The PDSN sends an intermediate charging request message to AAA, where the trigger type indicates that the rate switching trigger is triggered, and the request message includes the current status of the mobile terminal using the data service;

AAA determines the remaining cost of the allocated costs according to the current status, and determines whether the remaining costs are zero, and if so, sends a billing request message to the SCP for the application fee, and then according to the SCP's allocated fee and the new fee Rate control information; otherwise, control information is determined directly based on the remaining cost and the new rate

The AAA sends control information to the PDSN, and the PDSN resets a rate switching trigger, a session activation trigger, and / or a traffic trigger according to the control information.

22. The method according to claim 9, wherein the step of performing a leap on the mobile terminal comprises:

After determining that the user account balance is insufficient, the SCP sends an authentication request response message to the AAA indicating that the authentication has failed;

AAA sends the PDSN before the handover to instruct the PDSN to recycle and then the mobile terminal time before the handover The cost of allocating mobile terminals;

The PDSN before the handover sends the current status of the mobile terminal's data service to the AAA through a charging request message indicating the stop;

AAA determines the remaining cost according to the current state, and then returns the remaining cost to the SCP;

SCP returns the remaining charges to the user account, then allocates a fee for the mobile terminal, and sends the allocated fee to AAA;

The AAA instructs the PDSN to allow the mobile terminal to access, and controls the mobile terminal to use the data service according to the cost allocated by the SCP. '

23. The method according to claim 9, wherein the data network further comprises a data PPS, and the information exchange between the AAA and the SCP is forwarded through the data PPS.

24. The method according to claim 9, wherein the SCP further comprises a voice PPS, and the pre-established signaling transmission link between the SCP and AAA is to establish the voice between the PPS and AAA in the SCP. The signaling transmission link in step c; in step c, the SCP allocates a fee and returns the allocated fee to AAA by the voice PPS in the SCP.