CN101127694B

CN101127694B - A system and method for implementing policy and billing control

Info

Publication number: CN101127694B
Application number: CN2006101098587A
Authority: CN
Inventors: 胡华东; 张进
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2006-08-18
Filing date: 2006-08-18
Publication date: 2011-04-20
Anticipated expiration: 2026-08-18
Also published as: CN101127694A; WO2008022602A1

Abstract

The utility model provides a system and a method capable of realizing strategies and price charging control; when a piece of user equipment (UE) enters from the control range of a first strategy and price charging executive function (PCEF) entity to the control range of a second PCEF entity, the second PCEF entity can obtain strategies and price charging rules from the first PCEF entity, and can also obtain strategies and price charging rules from a strategy and price charging rule function (PCRF); then the second PCEF entity builds carrying with the UE; after that, the second PCEF entity opens a gate, and controls the business data flow of the present business of the UE according to the obtained strategy and price charging rules. By adopting the technical proposal of the utility model, the first PCEF entity can be switched into the second PCEF entity when the UE is entering from the control range of the first PCEF entity to the control range of the second PCEF entity; therefore, the second PCEF entity can replace the first PCEF entity and continue to control the business data flow of the present business of the UE, and objective of effective control from the system to the business is realized.

Description

System and method for realizing policy and charging control

Technical Field

The invention relates to a strategy and charging control technology in mobile communication, in particular to a system and a method for realizing the strategy and charging control.

Background

In order to control the traffic in the network and the resources used by the traffic, the operator typically implements policy and charging rules.

Currently, a Policy and Charging Control (PCC) framework is a functional standard for implementing Policy and Charging rules. In the PCC framework, a Policy and Charging Rules Function (PCRF) entity is a core for implementing the Policy and Charging Function, and the Policy and Charging Rules are mainly formulated according to network information related to formulating Policy and Charging Rules in a network where the PCEF (Policy and Charging Enforcement Function) entity is located. In practical applications, the PCRF entity may further formulate policy and charging rules according to information related to a service, which is obtained from an Application Function (AF) entity, and information related to a user Subscription specification, which is obtained from a Subscription Profile Repository (SPR) entity.

When a User Equipment (UE) uses a service, a Policy and Charging Enforcement Function (PCEF) located in a GateWay (GW) controls a service data flow of the current service of the UE according to Policy and Charging Rules established by a PCRF entity. The policy generally refers to information such as quality of service (QoS) and gating (gating), and the PCEF may control the traffic data flow of the current traffic of the UE according to the established policy. In addition, the PCEF may also perform traffic statistics on the service to achieve the purpose of charging.

In practical applications, the PCC framework may be applied to existing mobile communication networks, such as: general Packet Radio Service (GPRS) networks, interworking wireless local area networks (I-WLANs), data over coax interface specification (DOCSIS) networks, etc., and may also be applied in 3GPP (3 rd Generation Partnership Project) evolution networks.

However, regardless of the network type, in the prior art, when the UE is disconnected from the original gateway and accesses the network from a new gateway, that is, when the UE enters the control range of another second PCEF entity from the control range of the first PCEF entity, the first PCEF entity cannot control the service of the UE outside the control range, and the second PCEF entity does not obtain related information for controlling the service of the UE, such as a policy and a charging rule, at this time, the system cannot continue to perform policy and charging control on the service data flow of the current service of the UE, thereby affecting the effect of implementing the service.

Disclosure of Invention

The invention aims to provide a system for realizing policy and charging control, which can continuously carry out policy and charging control on the service data flow of the current service of UE when the UE enters the control range of a second PCEF entity from the control range of a first PCEF entity.

Another objective of the present invention is to provide a method for implementing policy and charging control, which can continue policy and charging control on the service data flow of the current service of the UE when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity.

Aiming at the first invention purpose, the technical scheme provided by the invention is as follows:

a system for realizing policy and charging control at least comprises a first Policy and Charging Enforcement Function (PCEF) entity, a second PCEF entity and a Policy and Charging Rule Function (PCRF) entity;

the first PCEF entity is used for controlling the service data flow of the current service of the user equipment UE within the control range of the first PCEF entity;

the PCRF entity is used for making a policy and charging rule;

and the second PCEF entity is used for acquiring the policy and charging rules from the first PCEF entity or from a Policy and Charging Rules Function (PCRF) entity when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, and controlling the service data flow of the current service of the UE according to the acquired policy and charging rules.

In the foregoing solution, the system further includes a mobility management function entity, where the mobility management function entity has address information of the second PCER, and the PCRF entity is further configured to obtain the address information of the second PCEF entity from the mobility management function entity, and send a policy and charging rule to the second PCEF entity according to the address information.

Aiming at the second invention purpose, the technical scheme of the invention is realized as follows:

a method for realizing policy and charging control, when User Equipment (UE) enters the control range of a second PCEF entity from the control range of a first policy and charging enforcement function (PCEF entity), the first PCEF entity is used for controlling the service data flow of the current service of the UE within the control range of the first PCEF entity, and the method comprises the following steps:

the second PCEF entity obtains the policy and charging rules from the first PCEF entity or from a Policy and Charging Rules Function (PCRF) entity, and the PCRF entity is used for making the policy and charging rules;

and the second PCEF controls the service data flow of the current service of the UE according to the acquired policy and charging rule.

In the foregoing solution, the method for the second PCEF entity to obtain the policy and charging rule from the first PCEF entity includes:

and the second PCEF entity receives the rule notification message which is sent by the first PCEF entity and carries the policy and charging rule, and directly acquires the policy and charging rule from the rule notification message.

In the above scheme, the obtaining, by the second PCEF entity, the policy and charging rule from the first PCEF entity is:

the second PCEF entity sends a rule request message to the first PCEF entity, receives a rule notification message which carries the policy and charging rule and is returned by the first PCEF entity, and acquires the policy and charging rule from the rule notification message.

In the foregoing solution, the method for the second PCEF entity to obtain the policy and charging rules from the PCRF entity includes:

the second PCEF entity or the first PCEF entity sends a rule request message to a Policy and Charging Rules Function (PCRF) entity, wherein the rule request message carries address information of the second PCEF entity, so that the PCRF entity establishes a session with the second PCEF entity according to the address information of the second PCEF entity, and sends the policy and charging rules stored by the PCRF entity to the second PCEF entity through a rule notification message.

In the above scheme, the obtaining, by the second PCEF entity, the policy and charging rules from the PCRF entity is:

the second PCEF and the PCRF entity establish a session according to address information and receive a policy and charging rule stored by the PCRF through a rule notification message, wherein the address information is address information of the second PCEF entity carried in a rule request message sent by the PCRF entity to the PCRF entity, and the mobility management function entity has the address information of the second PCEF entity.

In the foregoing solution, the rule request message further includes network information related to policy and charging rule making in a network where the second PCEF entity is located, and the sending the rule request message to the PCRF entity and establishing the session further includes:

the PCRF entity formulates a policy and charging rule according to network information related to formulation of the policy and charging rule in a network where the second PCEF entity is located;

the policy and charging rules sent by the PCRF entity to the second PCEF entity are: and the strategy and the charging rule are established according to the network information of the network where the second PCEF entity is positioned and relevant to the establishment of the strategy and charging rule.

In the foregoing solution, the step of the second PCEF entity obtaining the policy and charging rules from the first PCEF entity or from the policy and charging rules function PCRF entity, and the step of the second PCEF controlling the service data flow of the current service of the UE according to the obtained policy and charging rules further include:

the first PCEF entity closes a gate;

the second PCEF entity turns on gate.

In the foregoing solution, when an online charging manner is adopted, the first PCEF entity records the remaining credit value of the UE in real time according to a service usage condition of the UE, and a step of closing the gate by the first PCEF entity and a step of opening the gate by the second PCEF entity further include:

the first PCEF entity returns the residual credit value of the UE to an Online Charging System (OCS), and the OCS obtains the total residual credit value of the UE according to the returned residual credit value; the second PCEF entity sends a credit value request message to the OCS, and the OCS returns the available credit value distributed from the total remaining credit value to the second PCEF entity through a credit value request response message; the second PCEF entity judges whether the UE has the right to use the service according to the available credit value, and if so, the step of opening the gate by the second PCEF entity is executed; otherwise, the process is exited.

In the foregoing solution, when an offline charging manner is adopted, the first PCEF entity performs statistics on a service usage situation of the UE, and a step of the first PCEF entity closing a gate and a step of the second PCEF entity opening the gate further include:

and the first PCEF entity sends the statistical condition to an off-line charging system OFCS, and the OFCS charges according to the statistical condition of the first PCEF entity.

In the foregoing solution, the step of acquiring the policy and charging rule from the first PCEF entity or from the PCRF entity includes:

the first PCEF entity closes the gate;

the step of the second PCEF entity obtaining the policy and charging rules from the first PCEF entity or from the policy and charging rules function PCRF entity and the step of the second PCEF controlling the service data flow of the current service of the UE according to the obtained policy and charging rules further include:

the second PCEF entity turns on gate.

In the foregoing solution, when the system adopts an online charging manner, the first PCEF entity records the remaining credit value of the UE in real time according to the service usage condition of the UE, and the step of closing the gate by the first PCEF entity and the step of opening the gate by the second PCEF entity further include:

In the foregoing solution, when the system adopts an offline charging mode, the first PCEF entity performs statistics on the service usage condition of the UE, and a step of the first PCEF entity closing the gate and a step of the second PCEF entity opening the gate further include:

In the above scheme, the method further comprises:

the first PCEF entity, the second PCEF entity or the existing mobile management function entity notifies the PCRF entity of the PCEF updating information, and the PCRF entity replaces the stored first PCEF entity connection information with the second PCEF entity connection information according to the PCEF updating information.

In the foregoing solution, after the step of controlling, by the second PCEF, the service data flow of the current service of the UE according to the obtained policy and charging rule, the method further includes:

and when the PCRF entity formulates new policy and charging rules, the PCRF entity sends the new policy and charging rules to the second PCEF entity according to the second PCEF entity connection information.

In summary, the present invention provides a system and a method for implementing policy and charging control, which can, when a UE enters a control range of a second PCEF entity from a control range of a first PCEF entity, first obtain a policy and charging rule by the second PCEF entity, establish a bearer with the UE, then open a gate, and continue to control a service data flow of a current service of the UE according to the obtained policy and charging rule, so as to ensure an effect of implementing the service.

Drawings

FIG. 1 is a schematic diagram of a basic structure of a first embodiment of the system of the present invention;

FIG. 2 is a schematic diagram of a basic structure of a second embodiment of the system of the present invention;

FIG. 3 is a schematic diagram of a basic structure of a third embodiment of the system of the present invention;

FIG. 4 is a flow chart of an aspect of the present invention;

fig. 5 is a message flow diagram of a first embodiment of the method of the present invention;

fig. 6 is a message flow diagram of a second embodiment of the method of the present invention;

fig. 7 is a message flow diagram of a third embodiment of the method in the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

The system for realizing the policy and charging control at least comprises a first PCEF entity and a second PCEF entity.

The first PCEF entity is used for controlling the service data flow of the current service of the UE within the control range of the first PCEF entity;

and the second PCEF entity is used for acquiring the strategy and the charging rule when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, and controlling the service data flow of the current service of the UE according to the acquired strategy and charging rule.

In practical applications, the second PCEF may obtain the policy and charging rules through multiple approaches, and specifically, the policy and charging rules may be obtained from the first PCEF entity, or may be obtained through the PCRF entity.

When the policy and charging rule is obtained through the first PCEF, the specific obtaining process can also be implemented in various ways, for example: the first PCEF entity may send a rule notification message carrying the policy and charging rules to the second PCEF entity; the second PCEF entity obtains the policy and charging rules from the rule notification message.

Or,

the second PCEF entity sends a rule request message to the first PCEF entity and obtains a policy and charging rule from the returned rule notification message; and after receiving the rule request message from the second PCEF entity, the first PCEF entity returns a rule notification message carrying the policy and charging rules to the second PCEF entity.

Or,

when the policy and charging rules are acquired through the PCRF entity, the PCRF entity of the system is used for receiving a rule request message carrying address information of a second PCEF entity from a first PCEF entity, establishing a session with the second PCEF entity according to the address information of the second PCEF entity, and sending the policy and charging rules stored in the PCRF entity to the second PCEF entity through a rule notification message; the first PCEF entity is further used for sending a rule request message carrying the address information of the second PCEF entity to the PCRF; the second PCEF entity is further configured to establish a session with the PCRF and receive a rule notification message from the PCRF.

Or,

the PCRF entity is used for receiving a rule request message carrying address information of a second PCEF entity from the second PCEF entity, establishing a session with the second PCEF entity according to the address information of the second PCEF entity, and sending the policy and charging rule stored in the PCRF entity to the second PCEF entity through a rule notification message; the second PCEF entity is further configured to send a rule request message carrying address information of itself to the PCRF, establish a session with the PCRF, and receive a rule notification message carrying a policy and charging rule from the PCRF.

Or,

the system further comprises a mobility management function entity; the PCRF is used for receiving a rule request message carrying second PCEF entity address information from a mobile management function entity, establishing a session with the second PCEF according to the second PCEF address information, and sending a policy and charging rule stored by the PCRF to the second PCEF through a rule notification message; the mobility management function entity is used for sending the address information of the second PCEF entity to the PCRF through a rule request message; the second PCEF entity is further configured to establish a session with the PCRF, and receive a rule notification message carrying the policy and the charging rule from the PCRF.

In practical applications, the System may further include an Online Charging System (OCS) for receiving the UE remaining credit value returned from the first PCEF, allocating an available credit value according to the UE total remaining credit value, and returning the available credit value to the second PCEF entity; and the second PCEF entity controls the service data flow of the current service of the UE according to the available credit value.

Embodiment of the System

The first diagram shows the basic structure of the first embodiment of the system. As shown in fig. 1, the present embodiment includes: a first PCEF entity 101, a second PCEF entity 102, a PCRF entity 103, a mobility management function entity 104, and an OCS 105. Wherein,

the first PCEF entity 101 is configured to receive a handover trigger message sent by the mobility management function entity 104, send a rule request message to the PCRF entity 103 according to the handover trigger message, and receive a returned rule request response message; after obtaining the policy and charging rules from the rule request response message, close the gate, delete the rules, and return the UE remaining credit value to OCS entity 105, send a handover execution request message to PCRF entity 103, and return a handover trigger response message to mobility management function entity 104.

The second PCEF entity 102 is configured to receive a rule request response message carrying a policy and a charging rule from the PCRF entity 103, send a credit value request message to the OCS entity 105 after receiving a handover indication message sent by the PCRF entity 103, receive a returned credit value request message, open a gate, establish a bearer with the UE, and control a service data flow of a current service of the UE according to the obtained policy and the charging rule.

The PCRF entity 103 is configured to receive the rule request message from the first PCEF entity 101, formulate a policy and charging rule, send the policy and charging rule to the second PCEF entity 102 through the rule notification message, and send a handover indication message to the second PCEF entity 102.

The mobility management functional entity 104 is configured to send a handover trigger message and a handover execution trigger message to the first PCEF entity 101, and receive a returned handover trigger response message and a returned handover execution trigger response message.

When the UE enters the control range of the second PCEF entity 102 from the control range of the first PCEF entity 101, the mobility management functional entity 104 first sends a handover trigger message to the first PCEF entity 101, the second PCEF entity 102 sends a rule request message to the PCRF entity 103, and the PCRF entity 103 formulates a policy and a charging rule according to information carried by the rule request message, and sends the policy and the charging rule to the second PCEF entity 102; the second PCEF entity 102 establishes a bearer with the UE, and returns a handover trigger response message to the mobility management functional entity 104; the mobility management functional entity 104 sends a handover execution trigger message to the first PCEF entity 101, and the first PCEF closes the gate, deletes the rule, and returns the UE remaining credit value to the OCS entity 105; the first PCEF entity 101 then sends a handover execution request message to the PCRF entity 103, the PCRF entity 103 sends a handover indication message to the second PCEF entity 102, and after the second PCEF entity obtains the allocated available credit value from the OCS entity 105, the gate is opened, and the service data flow of the current service of the UE is controlled according to the obtained policy and charging rules.

Second embodiment of the System

Fig. 2 shows a schematic system structure of a second embodiment of the system. As shown in fig. 2, the present embodiment includes a first PCEF entity 201, a second PCEF entity 202, a PCRF entity 203, a mobility management function entity 204, and an OCS 205. Wherein,

the first PCEF entity 201 is configured to receive the handover execution message from the PCRF entity 203, return a handover execution response message, close the gate, delete the rule, and return the remaining credit value of the UE to the OCS entity 205.

The second PCEF entity 202 is configured to receive a rule notification message carrying a policy and a charging rule from the PCRF entity 203, establish a bearer with the UE, obtain an available credit value from the OCS entity 205, open a gate, and control a service data flow of a current service of the UE according to the obtained policy and the charging rule.

The PCRF entity 203 is configured to receive the rule request message from the mobility management function entity 204, send a handover execution message to the first PCEF entity 201, execute the policy and charging rule, and send the policy and charging rule to the second PCEF entity 202 through the rule notification message.

The mobility management function entity 204 is configured to send a rule request message to the PCRF entity 203, and receive a returned rule request response message.

The OCS entity 205 is configured to receive the UE remaining credit value from the first PCEF entity 201, and send the allocated available credit value to the second PCEF entity 202.

When the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity 201, the mobility management functional entity 201 sends a rule request message to the PCRF entity 203, the PCRF entity 203 sends a handover execution message to the first PCEF entity 201, the first PCRF entity 201 closes the gate again, deletes the policy and the charging rules, and returns the remaining credit value of the UE to the OCS entity 205, and then sends a handover execution response message to the PCRF entity 203; the PCRF entity 203 formulates policy and charging rules and sends them to the second PCEF entity 202; the second PCEF entity 202 establishes a bearer with the UE, obtains an available credit value from the OCS entity 205, then opens a gate, and controls the service data flow of the current service of the UE according to the obtained policy and charging rule.

Embodiment three of the System

Fig. 3 shows a schematic system structure of a third embodiment of the system. As shown in fig. 3, the present embodiment includes a first PCEF entity 301, a second PCEF entity 302, a PCRF entity 303, and a mobility management function entity 304.

The first PCEF entity 301 is configured to receive the rule request message from the second PCEF entity 302, and return the policy and charging rule stored in the first PCEF entity to the second PCEF entity 302; and is further configured to close the gate and send a handover indication message to the second PCEF entity after receiving the handover execution trigger message sent from the mobility management function entity 304.

The second PCEF entity 302 is configured to receive a handover trigger message from the mobility management function entity 304, send a rule request message to the first PCEF entity, and receive a returned policy and charging rule; sending a switching preparation notification message to the PCRF entity 303, and notifying the information of the PCEF sending the switching to the PCRF entity 303; and the method is also used for establishing a bearer with the UE, opening a gate and controlling the service data flow of the current service of the UE according to the obtained strategy and charging rule.

The PCRF entity 303 is configured to receive the handover preparation notification message from the second PCEF entity 302, and store the carried information of the PCEF handover.

The mobility management function entity 304 is configured to send a handover trigger message to the second PCEF entity 302, and send a handover execution trigger message to the first PCEF.

When the UE enters the control range of the second PCEF entity 302 from the control range of the first PCEF entity 301, the mobility management functional entity 304 sends a handover trigger message to the second PCEF entity 302, the second PCEF entity 302 sends a rule request message to the first PCEF entity 301, and the first PCEF entity 301 returns the policy and charging rules stored by itself to the second PCEF entity 302; the second PCEF entity 302 establishes a bearer with the UE, and sends information of PCEF handover to the PCRF entity 303 through the handover preparation notification message; after receiving the handover execution trigger message from the mobility management function entity 304, the first PCEF closes the gate, deletes the rule of the first PCEF, and sends a handover indication message to the second PCEF entity 302; and the second PCEF opens a gate and controls the service data flow of the current service of the UE according to the obtained strategy and charging rule.

The System for realizing the strategy and the charging control is a logical structure System, in practical application, a first PCEF Entity and a second PCEF Entity can be realized by a Gateway GPRS Support Node (GGSN) in the existing General Packet Radio Service (GPRS) network, and also can be realized by a User Plane Anchor (IASA) or an Inter Access System Anchor or a User Plane Entity (UPE) and the like between different Access systems in a future evolution network; the Mobility Management functional Entity may be implemented by two GPRS service Support nodes (SGSN) capable of communicating with each other in the GPRS network, or may be implemented by two Mobility Management Entities (MME) capable of communicating with each other in the future evolved network; in addition, the UPE and MME may also be implemented by the same network entity, i.e., MME// UPE entity. The entities in the system of the present invention are not listed in detail herein as to which network entity in the actual network is implemented in relation to the specific network design.

Aiming at the system for realizing the strategy and the charging control, the invention also provides a method for realizing the strategy and the charging control.

When the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the second PCEF entity acquires the strategy and the charging rule and replaces the first PCEF entity to control the service data flow of the current service of the UE.

Figure 4 shows a flow chart of the present invention. As shown in fig. 4, when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the method for implementing the policy and charging rules of the present invention includes the following steps:

step 401: the second PCEF entity obtains policy and charging rules.

In the present invention, there are many methods for the second PCEF entity to obtain policy and charging rules, and the methods can be roughly divided into two types:

the first method is to obtain policy and charging rules from the first PCEF entity, and this method is suitable for the case where the network information related to policy and charging rules in the network where the first PCEF entity is located is the same as the network information related to policy and charging rules in the network where the second PCEF entity is located. The network information related to the policy and charging rules establishment includes information such as an IP access type and a radio access technology. That is, the policy and charging rules to be enforced by the second PCEF entity are identical to those previously enforced by the first PCEF entity, without requiring re-formulation of policy and charging rules suitable for the second PCEF entity by the PCRF entity. For convenience of description, the network information related to the policy and charging rule making in the network where the first PCEF entity is located is simply referred to as original network information, and the network information related to the policy and charging rule making in the network where the second PCEF entity is located is simply referred to as new network information.

The method for the second PCEF entity to obtain the policy and charging rules from the first PCEF entity may be: the first PCEF entity sends a rule notification message carrying the policy and charging rules to a second PCEF entity, and the second PCEF entity directly obtains the policy and charging rules from the rule notification message; the method for the second PCEF entity to obtain the policy and charging rules from the first PCEF entity may also be: the second PCEF entity sends a rule request message to the first PCEF entity, the first PCEF entity returns a rule notification message carrying the policy and the charging rule to the second PCEF entity, and the second PCEF entity obtains the policy and the charging rule from the rule notification message.

The second method is to obtain policy and charging rules from the PCRF entity, which is generally suitable for the case where the new network information is different from the original network information, such as: the network where the first PCEF entity is located is GPRS, and the network where the second PCEF entity is located is I-WLAN. At this time, the PCRF entity needs to reformulate the policy and charging rule according to the new network information to control the service data flow of the current service of the UE.

The method for the second PCEF entity to obtain the policy and charging rules from the PCRF entity may be: the method comprises the steps that a first PCEF entity, a second PCEF entity or a mobile management function entity sends a rule request message to a PCRF entity, wherein the rule request message carries acquired address information and new network information of the second PCEF entity, the PCRF entity formulates a policy and charging rule according to the new network information, then establishes a session with the second PCEF entity according to the address information of the second PCEF entity, and then sends the formulated policy and charging rule to the second PCEF entity through a rule notification message.

Of course, in practical applications, if the new network information is the same as the original network information, the second PCEF entity may still obtain the policy and charging rules from the PCRF entity. However, the method in this case differs from the second method in that: the rule request message sent by the first PCEF entity, the second PCEF entity, or the mobility management function entity to the PCRF entity does not include the new network information. That is, the PCRF entity does not need to re-formulate the policy and charging rules, but only sends the already formulated policy and charging rules to the second PCEF entity, and obviously, the policy and charging rules described herein are the same as those in the first PCEF entity. The concrete implementation is as follows: the first PCEF entity, the second PCEF entity or the mobile management function entity sends a rule request message carrying address information of the second PCEF entity to the PCRF entity, the PCRF establishes a session with the second PCEF entity according to the address information of the second PCEF entity, and then sends the policy and charging rules stored by the PCRF entity to the second PCEF entity through the rule notification message.

When the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the mobility management functional entity may determine the address information of the second PCEF entity and the new network information itself, or obtain and determine the address information of the second PCEF entity and the new network information from the access side of the network. As for how the mobility management function entity or the access side of the network determines the address information of the second PCEF entity and the network information of the network where the second PCEF entity is located and related to the policy and charging rule making, which belongs to the prior art, details are not described here. In addition, how the PCRF entity formulates the policy and charging rules according to the network information related to formulating the policy and charging rules also belongs to the prior art, and is not described herein again.

After determining the address information of the second PCEF entity and the new network information, the mobility management function entity may send the address information of the second PCEF entity and the network information of the network where the second PCEF entity is located, which is related to the policy and charging rule formulation, to the first PCEF entity or the second PCEF entity through the handover trigger message, and the first PCEF entity or the second PCEF entity may send the rule request message to the PCRF entity. Of course, the mobility management function entity may also directly send the address information of the second PCEF entity and the new network information to the PCRF entity.

Step 102: and the second PCEF entity controls the service data flow of the current service of the UE according to the obtained strategy and charging rule.

The PCEF may identify a Service Data Flow (SDF) of the current Service of the UE according to the policy and charging rules, which is generally implemented by a Service Data Flow Template (SDF Template) in the policy and charging rules. After identifying the service data flow of the current service of the UE, the PCEF may perform policy and charging control on the service data flow according to the corresponding control indication in the policy and charging rules. These controls generally include operations such as QoS control, gating, and charging control, where QoS control refers to the PCEF controlling the Maximum Bit Rate (MBR), Guaranteed Bit Rate (GBR) of the upstream and downstream data flows identified by the policy and charging rules; the gating operation means that the PCEF constructs a plurality of gates according to the service data flow template information, and performs opening or closing operation on the gates according to the indication of the application layer. If the gate is opened, the PCEF enables the service data stream corresponding to the gate to pass through; if the gate is closed, the PCEF will discard the packet.

Before the second PCEF entity controls the traffic data flow of the current service of the UE, the first PCEF entity needs to close the gate, and the second PCEF entity needs to open the gate. The first PCEF entity may close the gate at the beginning when the UE enters the control range of the second PCEF entity, or may close the gate after the second PCEF entity establishes a bearer with the UE. After the first PCEF entity closes the gate, it may delete or continue to retain its own policy and charging rules. Of course, if the second PCEF entity needs to obtain the policy and charging rules from the first PCEF entity, the first PCEF entity needs to send the policy and charging rules to the second PCEF entity before deleting the policy and charging rules of itself. After the first PCEF entity deletes the policy and charging rules, bearers between the first PCEF entity and the UE need to be deleted, and network resources occupied by the bearers are released. When the first PCEF entity closes the gate, the second PCEF entity may open the gate after establishing a bearer with the UE, and further control the service data flow of the current service of the UE according to the obtained policy and charging rule.

Generally, in the process of controlling the service data flow of the current service of the UE, the PCEF may adopt an offline charging method or an online charging method.

If the offline charging method is adopted, the PCRF entity may include an offline charging indication in the policy and charging rules sent to the PCEF, and the PCEF performs offline charging on the service data stream identified by the policy and charging rules according to the offline charging indication, which is specifically implemented as: the PCEF counts the time, the flow and other conditions of the service data stream, that is, counts the service using conditions of the UE, and after the UE finishes using the service, sends the statistical conditions to an offline charging system (OFCS), and the OFCS charges according to the statistical conditions.

If the online charging method is adopted, the PCRF entity may include an online charging indication in the policy charging rule sent to the PCEF, and the PCEF performs online charging on the service data stream identified by the policy and charging rule according to the online charging indication, which is specifically implemented as: the PCEF firstly requests the available credit value of the UE from the OCS, and then records the residual credit value of the UE in real time according to the service using condition of the UE. The available credit value as described herein reflects the network resources that the UE can still use at the current charging price. Such as: if charging is carried out according to the time, the available credit value reflects the duration of the UE which can still receive or send the service data stream; if the charging is according to the flow, the available credit value reflects the flow that the UE can receive or send the service data flow. In addition, if the online charging method is adopted, the first PCEF entity needs to send the remaining credit value of the UE to the OCS between the gate turned off by the first PCEF entity and the gate turned on by the second PCEF entity, the OCS obtains the total remaining credit value of the UE according to the remaining credit value, and when the second PCEF entity requests the credit value from the OCS, the OCS sends the available credit value allocated from the total remaining credit value to the second PCEF entity.

In summary, in the solution of the present invention, which method is used by the second PCEF entity to obtain the policy and charging rules, when the first PCEF entity closes the gate and deletes the policy and charging rules of the first PCEF entity, and whether the system uses the online charging method or the offline charging method may be determined by the user applying the solution of the present invention, which is not described in detail herein.

In order to better illustrate the solution of the present invention, the method for implementing policy and charging rules according to the present invention is described below with a preferred embodiment.

Method embodiment one

In this embodiment, the original network information is different from the new network information, and the PCRF entity needs to make policy and charging rules according to the network information suitable for the network where the second PCEF entity is located; the method for the second PCEF entity to obtain the policy and charging rules is as follows: the first PCEF entity sends a rule request message to the PCRF entity, and the PCRF entity formulates a policy and a charging rule according to the related network information of the formulation rule of the network where the second PCEF entity is located, which is obtained from the rule request message, and sends the policy and the charging rule to the second PCEF entity; the first PCEF entity closes the gate after the second PCEF entity establishes the bearer with the UE; the system adopts an online charging mode, and before PCEF is switched, the first PCEF entity records the residual credit value of the UE in real time according to the service using condition of the UE.

Fig. 1 shows a system structure diagram of the present embodiment, and fig. 5 shows a message flow diagram of the present embodiment. As shown in fig. 5, when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the method for implementing policy and charging control includes the following steps:

step 501: and the mobile management functional entity sends a switching trigger message to the first PCEF entity, wherein the switching trigger message carries the address information of the second PCEF entity and the new network information.

The mobility management function entity may also send a PCEF handover trigger message to the second PCEF entity or the PCRF entity. Of course, whether the mobility management function sends the handover trigger message to the first PCEF entity, the second PCEF entity, or to the PCRF entity is determined by a specific implementation scheme.

Such as: when the UE enters the control range of the second PCEF entity, if the first PCEF entity or the second PCEF entity needs to send the rule request message to the PCRF entity, the handover trigger message may be first sent to the first PCEF entity or the second PCEF entity through the mobility management function entity, and the PCEF or the second PCEF entity is triggered to send the rule request message to the PCRF entity by the handover trigger message.

For the case that the second PCEF entity needs to send the rule request message to the PCRF entity, the mobility management function entity may also send the address information of the second PCEF entity and the new network information to the second PCEF entity through the bearer establishment request message, where the bearer establishment request message is equivalent to the handover trigger message.

For another example: when the UE enters the control range of the second PCEF entity, if the first PCEF entity is required to close its gate, the handover trigger message may be first sent to the first PCEF entity through the mobility management functional entity, so as to trigger the first PCEF entity to close its gate by using the handover trigger message.

For another example: when the UE enters the control range of the second PCEF entity, if the mobility management functional entity needs to send a rule request message carrying the address information of the second PCEF entity and the new network information to the PCRF entity, the rule request message may be directly used as a handover trigger message without sending a special handover trigger message.

In short, whether the mobility management function entity sends the handover trigger message is related to a specific scheme, and if the handover trigger message needs to be sent, the handover trigger message is sent to the entity which first executes the process of the scheme of the present invention, so as to trigger the entity to execute the subsequent process.

Step 502: and the first PCEF entity sends a rule request message to the PCRF entity, wherein the rule request message comprises the obtained address information of the second PCEF entity and the new network information.

Step 503 to step 504: and the PCRF entity formulates a policy and charging rule according to the new network information, establishes a session with the second PCEF entity according to the address information of the second PCEF entity, and sends the formulated policy and charging rule to the second PCEF entity through a rule notification message.

The PCRF entity may store connection information of the first PCEF entity, where the connection information is used to record a correspondence between the PCEF and the UE. When the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the PCRF entity receives PCEF updating information in the interaction process of the UE and the first PCEF entity, the second PCEF entity or the mobility management function entity, and the PCRF entity replaces the first PCEF entity connection information stored in advance with second PCEF entity connection information according to the PCEF updating information. After that, when the service information on the AF, the user subscription information on the SPR, or the configuration information of the PCRF entity itself changes, the policy and charging rule changes accordingly, and the PCRF entity may accurately send the changed policy and charging rule to the second PCEF entity for execution according to the recorded connection information of the second PCEF entity.

The PCEF connectivity information may be address information of the PCEF, and the PCEF update information may include first PCEF entity address information, second PCEF entity address information, and the UE identity. When UE enters a control range of a second PCEF entity from the control range of a first PCEF entity, the second PCEF entity or a mobile management functional entity sends first PCEF entity address information, second PCEF entity address information and a UE identifier which are obtained in advance to a PCRF entity, and the PCRF entity determines first PCEF entity address information corresponding to the UE identifier according to the UE identifier and replaces the first PCEF entity address information with the second PCEF entity address information. The PCRF entity may also record the PCEF handover situation by using other methods, as long as the new policy and charging rules can be accurately sent to the second PCEF entity when the new policy and charging rules are formulated.

In this embodiment, since the PCRF entity needs to send the policy and charging rules to the second PCEF entity, the PCRF entity may record the PCEF update information when receiving the rule request message. In practical application, if the PCRF entity does not need to make policy and charging rules for the second PCEF entity, after the second PCEF entity obtains the policy and charging rules from the first PCEF entity, the first PCEF entity or the second PCEF entity notifies the PCRF entity of the PCEF update information, and the PCRF entity replaces the first PCEF entity connection information stored in advance with the second PCEF entity connection information according to the PCEF update information.

Step 505: the second PCEF entity establishes a bearer with the UE.

After obtaining the policy and charging rule, the second PCEF entity may execute the policy and charging rule, and establish a bearer with the UE according to information such as QoS in the policy and charging rule, thereby completing network resource reservation. However, it should be noted that at this time, the gate in the second PCEF entity is still closed, and does not interact with the OCS or OFCS, and does not actually control the service.

Step 506 to step 508: the second PCEF entity sends a rule notification response message to the PCRF entity, the PCRF entity sends a rule request response message to the first PCEF entity, and the first PCEF entity sends a switching trigger response message to the mobility management function entity.

Step 509: and the mobility management functional entity sends a switching execution trigger message to the first PCEF entity.

Step 510: and the first PCEF entity closes the gate and deletes the own policy and charging rule.

Generally, the first PCEF entity also needs to delete the bearer established with the UE and release the network resources.

Step 511 to step 512: and the first PCEF entity sends the residual credit value of the UE to the OCS through a credit value notification message, and the OCS returns a credit value response message to the first PCEF entity.

Step 513 to step 514: the first PCEF entity sends a switching execution request message to the PCRF entity, and the PCRF entity sends a switching indication message to the second PCEF entity.

Step 515 to step 516: the second PCEF entity sends a credit value request message to the OCS, the OCS returns the available credit value allocated to the UE to the second PCEF entity through a credit value request response message, the second PCEF entity judges whether the UE has the right to use the service according to the available credit value of the UE, if so, step 517 is executed; otherwise, the process is exited.

517: and the second PCEF entity opens a gate and controls the service data flow according to the obtained strategy and charging rule.

Step 518 to step 520: the second PCEF entity returns a switching indication response message to the PCRF entity, the PCRF entity returns a switching execution request response message to the first PCEF entity, and the first PCEF entity returns a switching execution trigger response message to the mobility management function entity.

In this embodiment, steps 501 to 508 are a handover preparation phase, in which the second PCEF entity obtains the policy and charging rule, establishes a bearer with the UE, and prepares for handover, and meanwhile, the first PCEF entity still controls the service of the UE. Step 509 to step 520 are the handover execution phase, in which the second PCEF entity replaces the first PCEF entity to control the service, and charges the UE according to the obtained remaining credit value.

Method embodiment two

In this embodiment, the first PCEF entity and the second PCEF entity have different network information related to policy and charging decisions, and the PCRF entity needs to reformulate a policy and charging rule suitable for the network where the second PCEF entity is located; the method for the second PCEF entity to obtain the policy and charging rules is as follows: the mobile management function entity sends a rule request message to the PCRF entity, the PCRF entity formulates a policy and charging rule, and then the formulated policy and charging rule is sent to a second PCEF entity through a rule notification message.

In addition, in this embodiment, the system records the remaining credit value of the UE in real time in an online charging manner according to the service usage condition of the UE.

Fig. 2 shows a system structure diagram of the present embodiment, and fig. 6 shows a message flow diagram of the present embodiment. As shown in fig. 6, when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the method for implementing policy and charging control includes the following steps:

step 601: and the mobile management functional entity sends a rule request message to the PCRF entity, wherein the rule request carries the address information of the second PCEF entity and the new network information.

In this embodiment, the mobility management functional entity may directly use the rule request message described in this step as a handover trigger message, and does not need to specially send the handover trigger message. Of course, if the original network information and the new network information are the same, the rule request message described herein may include only the address information of the second PCEF entity.

Step 602: after receiving the rule request message, the PCRF entity first sends a handover execution message to the first PCEF entity.

Step 603: and after receiving the switching execution message, the first PCEF entity closes the gate and deletes the policy and charging rule of the first PCEF entity.

Generally, the first PCEF entity also needs to delete the bearer established between the first PCEF entity and the UE and release network resources.

Step 604 to step 605: and the first PCEF entity sends the residual credit value of the UE to the OCS through a credit value notification message, and the OCS returns a credit value response message to the first PCEF entity.

Step 606: the first PCEF entity sends a handover execution response message to the PCRF entity.

Step 607 to step 608: the PCRF entity formulates a policy and charging rule according to network information of a network where the second PCEF entity is located and related to formulation of the policy and charging rule, establishes a session with the second PCEF entity according to address information of the second PCEF entity, and sends the formulated policy and charging rule to the second PCEF entity through a rule notification message.

Step 609: and the second PCEF entity establishes a bearer with the UE and completes resource reservation.

Step 610 to step 611: the second PCEF entity sends a credit value request message to the OCS, the OCS returns an available credit value allocated from the total remaining credit value of the UE to the second PCEF entity through a credit value request response message, the second PCEF entity determines whether the UE is authorized to use the service according to the available credit value of the UE, and if so, step 612 is executed; otherwise, the process is exited.

Step 612: and the second PCEF entity opens a gate and controls the service data flow according to the obtained strategy and charging rule.

Step 613: and the second PCEF entity returns a rule notification response message to the PCRF entity, and the PCRF entity returns a rule request response message to the mobility management function entity.

In this embodiment, there are no strict handover preparation stage and handover execution stage, that is, the first PCEF entity first closes the gate and then performs handover preparation, the second PCEF entity obtains the policy and charging rule and establishes a bearer with the UE, and then the second PCEF entity opens the gate and controls the service according to the obtained policy and charging rule.

Method embodiment three

In the embodiment, the original network information is the same as the new network information, and the PCRF entity does not need to re-formulate the policy and charging rules; the method for the second PCEF entity to obtain the policy and charging rules is as follows: the second PCEF entity sends a rule request message to the first PCEF entity, the first PCEF entity returns a rule notification message carrying the policy and the charging rule to the second PCEF entity, and the second PCEF entity obtains the policy and the charging rule from the rule notification message.

Fig. 3 shows a system structure diagram of the present embodiment, and fig. 7 shows a message flow diagram of the present embodiment. As shown in fig. 7, when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the method for implementing policy and charging control includes the following steps:

step 701: and the mobility management functional entity sends a switching trigger message carrying the address information of the first PCEF entity to the second PCEF entity.

Step 702 to step 703: and the second PCEF entity sends a rule request message to the first PCEF entity according to the first PCEF entity address, and the first PCEF entity returns the own policy and charging rule to the second PCEF entity through a rule notification message.

Step 704: the second PCEF entity establishes a bearer with the UE.

In practical application, after the second PCEF entity obtains the policy and charging rule, the policy and charging rule may be executed, and a bearer may be established with the UE according to information such as QoS in the policy and charging rule, so as to complete network resource reservation. However, it should be noted that at this time, the gate in the second PCEF entity is still closed, and does not interact with the OCS or OFCS, and does not actually control the service.

Step 705 to step 706: and the second PCEF entity sends a switching preparation notification message to the PCRF entity, and the PCRF entity returns a switching preparation notification response message to the second PCEF entity.

Step 707: and the second PCEF entity returns a switching trigger response message to the mobility management function entity.

Step 708: and the mobility management functional entity sends a switching execution trigger message to the first PCEF entity.

Step 709: and the first PCEF entity closes the gate and deletes the own policy and charging rule.

If the offline charging method is adopted, the first PCEF entity always performs offline charging on the service data stream of the UE before closing the gate, and performs statistics on the conditions of time, traffic, and the like on the service data stream, that is, statistics on the service using condition of the UE. When the gate is closed, the first PCEF entity also needs to send the statistical condition to the OFCS, and the OFCS charges according to the statistical condition and generates a phone bill.

If the system adopts the online charging method, the first PCEF entity needs to return the remaining credit value of the user to the OCS after closing the gate, and the second PCEF entity obtains the remaining credit value of the user from the OCS before opening the gate.

Step 710: the first PCEF entity sends a handover indication message to the second PCEF entity.

If the online charging method is adopted, the OCS may also send a handover indication to the second PCEF entity after obtaining the remaining credit value of the user.

Step 711: and the second PCEF entity opens a gate and controls the service data flow according to the obtained strategy and charging rule.

Obviously, the policy and charging rules used by the second PCEF entity here are the same policy and charging rules as the first PCEF entity.

Step 712 to step 713: and the second PCEF entity sends a switching completion notification message to the PCRF entity, and the PCRF entity returns a switching completion notification response message to the second PCEF entity.

In this embodiment, the second PCEF entity may send the PCEF update information to the PCRF entity through the handover preparation notification message or the handover completion notification message in step 705 or step 712, and the PCRF entity replaces the first PCEF entity connection information recorded in advance with the second PCEF entity connection information according to the PCEF update information. Thus, when any one of the service information on the AF, the user subscription information on the SPR or the configuration information of the PCRF entity itself changes, the PCRF entity formulates a new policy charging rule, and then accurately sends the formulated policy charging rule to the second PCEF entity for execution according to the connection information of the second PCEF entity.

Step 714 to step 715: the second PCEF entity returns a switching indication response message to the first PCEF entity, and the first PCEF entity returns a switching execution response message to the mobility management function entity.

In this embodiment, steps 701 to 707 are switching preparation stages, and steps 708 to 715 are switching execution stages. In the switching preparation stage, the second PCEF entity firstly obtains a strategy and a charging rule from the first PCEF entity and establishes a load with the UE; in the switching execution phase, the second PCEF entity opens the gate, and controls the service data flow of the UE according to the obtained policy and charging rule. In this embodiment, the two phases are both triggered by the mobility management function entity and then started to be executed, but in practical application, the two phases may not be obviously separated and are triggered only once by the mobility management function entity. Such as: the mobility management function entity may not send the handover execution trigger message to the first PCEF entity and may omit steps 707 and 708. In addition, in this embodiment, the messages to be sent generally appear in pairs, but in practical application, they may not appear in pairs. Such as: after the second PCEF entity sends the handover completion notification message to the PCRF entity, the procedure may be directly ended without executing a subsequent response message, i.e., steps 713 to 715 may be omitted. In addition, if the PCEF update information has been sent to the PCRF entity through the handover preparation notification message in step 705, the handover completion notification message may not be sent, i.e., step 712 and step 713 are omitted.

By applying the scheme of the invention, when the UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the second PCEF entity can acquire the strategy and the charging rule for controlling the service data flow of the current service of the UE to replace the first PCEF entity to continue to control the current service of the UE. As for how the second PCEF entity obtains the policy and charging rules, when the first PCEF entity closes the gate, whether an offline charging method or an online charging method is adopted, which entity triggers the second PCEF entity opens the gate, whether the PCRF entity needs to formulate the policy and charging rules according to the network information of the network where the second PCEF entity is located and related to the formulation of the policy and charging rules, how PCEF update information is sent to the PCRF entity, which entity the mobility management function entity sends the handover trigger message, whether the handover preparation stage and the handover execution stage are separately executed or mixedly executed, and the like, are all related to specific schemes, and can be determined by the user applying the scheme of the present invention, and there is no one-to-one enumeration here.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for realizing policy and charging control at least comprises a first Policy and Charging Enforcement Function (PCEF) entity, a second PCEF entity and a Policy and Charging Rule Function (PCRF) entity, and is characterized in that:

the PCRF entity is used for making a policy and charging rule;

2. The system of claim 1, wherein the PCRF entity is further configured to obtain address information of the second PCEF entity from the first PCEF entity or the second PCEF entity, and send policy and charging rules to the second PCEF entity according to the address information.

3. The system of claim 1, wherein the system further comprises a mobility management function entity, the mobility management function entity has address information of the second PCEF entity, and the PCRF entity is further configured to obtain the address information of the second PCEF entity from the mobility management function entity, and send the policy and charging rules to the second PCEF entity according to the address information.

4. A method for implementing policy and charging control, the method comprising the steps of:

the first Policy and Charging Enforcement Function (PCEF) entity is used for controlling the service data flow of the current service of the User Equipment (UE) within the control range of the PCEF entity;

the policy and charging rules function PCRF entity is used for making policy and charging rules;

when the user equipment UE enters the control range of the second PCEF entity from the control range of the first PCEF entity, the second PCEF entity acquires the policy and the charging rule from the first PCEF entity or from the PCRF entity, and the second PCEF entity controls the service data flow of the current service of the UE according to the acquired policy and the charging rule.

5. The method of claim 4, wherein the obtaining, by the second PCEF entity, the policy and charging rules from the first PCEF entity is:

6. The method of claim 4, wherein the obtaining, by the second PCEF entity, the policy and charging rules from the first PCEF entity is:

7. The method of claim 4, wherein the obtaining of the policy and charging rules from the PCRF entity by the second PCEF entity is:

8. The method of claim 4, wherein the obtaining of the policy and charging rules from the PCRF entity by the second PCEF entity is:

the second PCEF entity and the PCRF entity establish a session according to address information and receive policy and charging rules stored by the PCRF entity and sent by a rule notification message, wherein the address information is address information of the second PCEF entity carried in a rule request message sent by a mobility management functional entity to the PCRF entity, and the mobility management functional entity has the address information of the second PCEF entity.

9. The method of claim 7 or 8, wherein the rule request message further includes network information related to policy and charging rules establishment in a network in which the second PCEF entity is located, and wherein the sending the rule request message to the PCRF entity and establishing the session further includes:

10. The method of claim 4, wherein the step of the second PCEF entity obtaining the policy and charging rules from the first PCEF entity or from the policy and charging rules function PCRF entity, and the step of the second PCEF entity controlling the traffic data flow of the current UE traffic according to the obtained policy and charging rules further comprise:

the first PCEF entity closes a gate;

the second PCEF entity turns on gate.

11. The method as claimed in claim 10, wherein when an online charging mode is adopted, the first PCEF entity records the remaining credit value of the UE in real time according to a service usage condition of the UE, and the step of the first PCEF entity closing the gate and the step of the second PCEF entity opening the gate further include:

12. The method as claimed in claim 10, wherein when the offline charging mode is adopted, the first PCEF entity performs statistics on the service usage of the UE, and wherein the step of the first PCEF entity closing the gate and the step of the second PCEF entity opening the gate further include:

13. The method of claim 4, wherein the step of the second PCEF entity obtaining the policy and charging rules from the first PCEF entity or from a Policy and Charging Rules Function (PCRF) entity further comprises:

the first PCEF entity closes the gate;

the step of the second PCEF entity obtaining the policy and charging rules from the first PCEF entity or from the policy and charging rules function PCRF entity and the step of the second PCEF entity controlling the service data flow of the current service of the UE according to the obtained policy and charging rules further include:

the second PCEF entity turns on gate.

14. The method as claimed in claim 13, wherein when the system employs an online charging mode, the first PCEF entity records the remaining credit value of the UE in real time according to a service usage condition of the UE, and wherein the step of closing the gate by the first PCEF entity and the step of opening the gate by the second PCEF entity further include:

15. The method as claimed in claim 13, wherein when the system adopts an offline charging mode, the first PCEF entity performs statistics on the service usage of the UE, and wherein the step of closing the gate by the first PCEF entity and the step of opening the gate by the second PCEF entity further include:

16. The method of claim 4, further comprising:

the first PCEF entity, the second PCEF entity or the mobile management function entity notifies the PCRF entity of the PCEF entity updating information, and the PCRF entity replaces the stored first PCEF entity connection information with second PCEF entity connection information according to the PCEF entity updating information.

17. The method as claimed in claim 16, wherein after the step of controlling, by the second PCEF entity, the service data flow of the current service of the UE according to the obtained policy and charging rules, the method further comprises: