CN102387558B

CN102387558B - A kind of method and system of releasing resource network resources in evolved network switching process

Info

Publication number: CN102387558B
Application number: CN201110329177.2A
Authority: CN
Inventors: 朱文若; 帅扬来; 胡华东; 邓婷婷
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2007-08-21
Filing date: 2007-08-21
Publication date: 2015-08-19
Anticipated expiration: 2027-08-21
Also published as: CN102387558A; CN101374339B; CN101374339A

Abstract

The invention discloses a kind of method and system of releasing resource network resources in evolved network switching process, by in objective network carrying foundation or after setting up, PCRF is by release that is synchronous or asynchronous controlling source network resource, in the dispose procedure of the Synchronization Control source network resource of PCRF, objective network transmit a request to PCRF, and requirement generates new PCC rule to objective network, after completing objective network carrying foundation, send message informing PCRF, trigger the process that PCRF initiates source network carrying release; Asynchronous process of carrying out objective network carrying foundation and the release of source network resource, namely PCRF receive objective network send IP access to network conversation set up message after, send PCC to determine to provide message to source network IAD, require carrying and the related resource of source of release network, application the present invention, can make terminal switch after objective network from source network, can carry out the release of source network bearing resource in time, improve the service efficiency of source network bearing resource, reduce the waste of resource.

Description

Method and system for releasing source network resources in evolution network switching process

Technical Field

The present invention relates to network handover technologies, and in particular, to a method and a system for releasing source network resources in an evolved network handover process.

Background

In order to guarantee the competitiveness of the third Generation mobile communication standardization Partnership Project (3 GPP) system for 10 years or more in the future, evolution-related access technologies are being enacted within the 3GPP organization, and particularly to enhance the capability of the 3GPP system to handle the rapidly increasing IP data traffic, the usage packet technology within the 3GPP system needs to be further enhanced. Networks including these Evolved Packet technologies are called Evolved Packet Systems (EPS), and the most important parts of the Evolved technologies include: the time delay is reduced, the user data rate is higher, the system capacity and the coverage are enhanced, the overall cost of an operator is reduced, and the EPS network structure has backward compatibility with the existing network; furthermore, the EPS network architecture also needs to satisfy the following points:

1. in an initialization stage of a User Equipment (UE), such as a terminal access network, a basic IP connection needs to be established in an evolved network;

2. the evolved network architecture must minimize the latency of user data;

3. the definition of each functional module in the evolved network architecture should avoid overlapping or repetition of functions to avoid unnecessary signaling interaction and delay.

Fig. 1 is a schematic diagram of a non-roaming architecture of a conventional EPS network. Referring to fig. 1, the Network architecture mainly includes a Mobility Management Entity (MME), a Serving Gateway (ServingGateway), a Packet Data Network Gateway (PDN Gateway), an Evolved UMTS terrestrial radio access Network (E-UTRAN), and a Policy and Charging rule function Entity (PCRF), where the E-UTRAN is connected to the MME through an S1-MME interface, the MME is connected to the Serving Gateway through an S11 interface, the Serving Gateway is connected to the PDN Gateway through an S5 interface, and the Serving Gateway and the PDN Gateway are connected to the PCRF through an S7 interface.

Fig. 2 is a schematic diagram of a roaming architecture of a conventional EPS network. Referring to fig. 2, the EPS Network roaming architecture is mainly based on a Policy and Charging Control (PCC) architecture of a decentralized Policy and Charging enhancement function entity (PCEF), and is divided into three parts by a Visited Public Mobile Network (VPLMN) and a Home Public Mobile Network (HPLMN, Home PLMN), where an Evolved Packet Core Network (EPC) of the EPS Network mainly includes an MME, a Serving Gateway, and a PDN Gateway. The MME is responsible for mobility management of a control plane, including user context and mobility state management, allocating user temporary identity, security function, and the like, and corresponds to a control plane part of a Serving General Packet Radio Service Support Node (SGSN) in a current Universal Mobile Telecommunications System (UMTS); the Serving Gateway is a user plane anchor point between different access systems in the 3GPP system, directly faces the access of the 3GPP access system, is a user plane anchor point between the 3GPP internal access systems, and can also be used as a local user plane anchor point between a non-3GPP access system and the 3GPP access system in a roaming scene, and one user can only have one Serving Gateway in a time period; the PDN Gateway is a user plane anchor point between a 3GPP access system and a non-3GPP system in the EPS system, and provides a PDN access for a user. The MME is connected with a Serving Gateway through an S11 interface, the Serving Gateway is connected with a PDN Gateway through an S8b interface, and the Serving Gateway and the PDNGgateway form an EPS Gateway (EPS GW, EPS Gateway).

When 3GPP accesses, PCEF logic function entities are arranged on a Home Agent (HA), such as PDN GW, and an Access Gateway (AGW, Access Gateway) of 3GPP, such as Serving GW; when non3GPP accesses, PCEF logical function entities are set on HA and AGW of non3GPP access system (non3GPP), such as Evolved Packet Data Gateway (ePDG) or AGW of trusted non3GPP access system, that is, PCEF logical function entities are set on four entities of Serving GW, PDN GW, ePDG and AGW of trusted non3 GPP.

As shown by dotted lines in fig. 1 and fig. 2, the PCRF and the Serving GW, the PDN GW, the ePDG and the AGW of the trusted non-3GPP are all connected through an S7 interface, the S2a interface is an interface for the trusted non-3GPP to access to the EPS, and is mainly based on Internet-based Proxy mobile IP v6(PMIPv6, Proxy mobile IP) and Foreign Agent (FA, Foreign Agent) protocols such as Internet Engineering Task Force (IETF) protocol of client mobile IP (CMIPv4FA, common management IPv4 FA); the S2b interface is an interface for untrusted non-3GPP to access to EPS, the EPC needs to provide a gateway entity ePDG to ensure the security of untrusted non-3GPP access, and is mainly based on network-based (PMIPv6) IETF protocol; the S2c interface is a trusted/untrusted/LTE/Legacy 3GPP access system, and is based on a host-based Collocated Care-of-address (COA, Care-of-address) mode (CMIPv 6).

With the increasing demand for terminal mobility, the common IP technology cannot support the movement of an IP terminal, and therefore, a mobile IP technology is generated on the basis of the common IP technology, so that the terminal can not change its Home address when moving, when the terminal moves to a non-Home network, a COA belonging to the current network is obtained, and the COA and the Home-of-address (HOA) of the terminal are bound, when a packet is sent to the HOA of the terminal, the HA of the terminal sends the packet to the care-of-address, thereby completing routing, mainly including CMIP and PMIP technologies, where the CMIP is a host-based mobile IP technology, that is, a binding process requiring the terminal to participate in the mobile IP; PMIP is a mobile IP technology based on a network, and the network can proxy the behavior of the terminal instead of initiating mobile IP binding without the terminal participating in the process of mobile IP. In fig. 1, the S2a interface, the S2b interface, and the S2c interface are mainly based on CMIP and PMIP.

In fig. 1 and 2, the function of the S7 interface has not been finalized, and how the MME, Serving Gateway, and PDN Gateway are combined in the corresponding entities has not been determined.

A Wireless Local Area Network (WLAN) is a widely existing Wireless access system, and in order to enable a user to access a 3GPP system more conveniently and use various services in the 3GPP system, the 3GPP has established an Interworking WLAN (IWLAN) project, and studies the Interworking problem between the WLAN and the 3GPP system, so that the user of the 3GPP system can access the 3GPP system through the WLAN.

Fig. 3 is a schematic diagram of a conventional wlan interconnection system architecture. Referring to fig. 3, the system architecture includes a WLAN UE, a WLAN Access Network (WLAN Access Network), an Intranet/Internet and a 3GPP Home Network (3GPP Home Network), wherein the WLAN UE accesses the WLAN Access Network through a Ww interface to interact with the Intranet/Internet, the WLAN Access Network is connected to the 3GPP Home Network through Wa and Wn interfaces, and in the 3GPP Home Network, the WLAN UE is authenticated and a 3GPP service is provided to the WLAN UE.

It should be noted that, according to the latest research results of 3GPP, the architecture in fig. 3 is not only applicable to the Access system in the WLAN mode, but also applicable to any Access mode based on the IP technology, such as Worldwide Interoperability for Microwave Access (WiMAX) and Asymmetric Digital Subscriber Line (ADSL).

After entering a network, if the terminal needs to leave a source network where the terminal is located and enter another target network, network switching needs to be performed, and in the switching process, in order to ensure service continuity, a bearer in the source network needs to be switched to the target network, including a target network bearer establishment process and a source network bearer release process. After the terminal completes the handover to the target network, the source network bearer in the idle state needs to be released to improve the utilization rate of resources.

The network handover includes handover between homogeneous networks and handover between heterogeneous networks, and handover between homogeneous networks, such as handover between 3GPP networks, because there is a connection between control plane entities MME or SGSN of two networks, after the terminal is handed over to the target network, the target network MME or SGSN will release resources through the MME or SGSN of the source network;

for the switching of heterogeneous networks, because there is no direct interface between the control plane entities of the two networks, the release of the bearer of the source network needs to have an interface with both networks, and the entity triggering the opportunity can be grasped by knowing the establishment condition of the bearer of the target network, so that the entity notifies the source network to release the bearer. Different IETF protocol based handover procedures between trusted non-3GPP and 3GPP, and between untrusted non-3GPP and 3GPP, are provided in the protocol 3GPP protocol standards.

Fig. 4 is a schematic diagram illustrating a handover procedure between a non-roaming PMIPv 6-based scenario and a trusted non-3GPP in the conventional S2a and S5 interfaces. Referring to fig. 4, the process includes:

step 401, a terminal establishes a connection with an Evolved UMTS terrestrial Radio Access Network (E-UTRAN) Access Network, and performs service data Access through the established connection;

in this step, a PMIPv6 tunnel is formed between the Serving GW and the PDN GW, and a connection may or may not be established between the PDN GW and the PCRF.

Step 402, the terminal finds a trusted non-3GPP access network, and selects the trusted non-3GPP access network to prepare for switching;

step 403, the terminal establishes a connection to the trusted non-3GPP access network;

in this step, the process of establishing the connection is specified by the trusted non-3GPP access network.

Step 404, performing an Extensible Authentication Protocol (EAP) Authentication process between the trusted non-3GPP access network and an Authentication, Authorization and Accounting Server (AAAServer);

in this step, in the authentication process, the AAA Server sends the IP address of the PDN GW to a trusted non-3GPP terminal Mobile Agent (PMA).

Step 405, after the EAP authentication process is successfully completed, triggering an attachment procedure;

step 406, the PMA of the trusted non-3GPP sends a Proxy binding message (PBU) to the PDN GW;

step 407, the PDN GW creates or modifies a Binding Cache Entry (BCE) for the terminal, and returns the allocated IP address to the PMA of the trusted non-3 GPP;

step 408, establishing a PMIP tunnel between the trusted non-3GPP and the PDN GW;

step 409, the network attach procedure is completed.

In this step, the terminal establishes connection with the PDN GW, and there is uplink and downlink data transmission, and the terminal recovers the service through the trusted non-3GPP access network to perform data transmission.

As can be seen from fig. 4, in the current handover procedure, after the terminal is successfully handed over from the source network to the target network, the bearer of the source network is always in an idle state, and there is no consideration for releasing the bearer resource of the source network in time.

Disclosure of Invention

In view of this, an objective of the embodiments of the present invention is to provide a method for releasing source network resources in an evolved network handover process, so as to improve the utilization rate of network resources.

Another object of the embodiments of the present invention is to provide a system for releasing source network resources in an evolved network handover process, so as to improve the utilization efficiency of network resources.

In order to achieve the above purpose, the technical solution of the embodiment of the present invention is specifically realized as follows:

a method for releasing source network resources in an evolution network switching process comprises the following steps:

when a terminal is switched to a target network from a source network, after the target network establishes an IP access network session IP-CAN bearer, a Policy and Charging Rules Function (PCRF) entity receives an IP-CAN session establishment completion response message;

and the PCRF issues a Policy and Charging Control (PCC) decision and provides a message to a source network access gateway or a network anchor point so that the source network access gateway or the network anchor point releases the load and related resources in the source network.

when a terminal is switched to a target network from a source network, after a Policy and Charging Rules Function (PCRF) receives an IP-CAN session establishment indication message, the PCRF issues a Policy and Charging Control (PCC) decision to provide a message to an access gateway or a network anchor point of the source network, so that the access gateway or the network anchor point of the source network releases a load and related resources in the source network.

A system for releasing source network resources during an evolved network handover, the system comprising: a target network access gateway, a PCRF, a network anchor point and a source network access gateway, wherein,

the target network access gateway is used for sending an IP-CAN session establishment indication message to the PCRF after the terminal is connected with the network, receiving an IP-CAN session establishment response message, initiating IP-CAN bearer establishment of the target network according to PCC rule information carried by the received IP-CAN session establishment response message, and sending an IP-CAN session establishment completion response message to the PCRF;

the PCRF is used for receiving the IP-CAN session establishment indication message output by the target network access gateway, generating corresponding PCC rule information, carrying the PCC rule information in the IP-CAN session establishment response message, sending the PCC rule information to the target network access gateway, receiving the IP-CAN session establishment completion response message sent by the target network access gateway, sending the PCC decision providing message to the network anchor point, carrying the PCC rule information required by the network anchor point to delete the corresponding PCC rule information, and receiving the PCC decision providing response message sent by the network anchor point;

the network anchor point comprises a PCEF (policy and charging control) used for policy and charging control by a source network, receives a PCC decision providing message issued by the PCRF, triggers the PCEF to send a resource release message to a source network access gateway, and sends a PCC decision providing response message to the PCRF;

and the source network access gateway is connected with the network anchor point based on the GPRS tunnel protocol, receives a resource release message sent by the network anchor point and releases corresponding load and related resources in the source network.

the PCRF is used for issuing a charging rule to a network anchor point, receiving an IP-CAN session establishment indication message output by a target network access gateway, generating corresponding PCC rule information, carrying the PCC rule information in an IP-CAN session establishment response message, sending the PCC rule information to the target network access gateway, receiving an IP-CAN session establishment completion response message sent by the target network access gateway, issuing a PCC decision providing message to a source network access gateway, requiring the source network access gateway to delete the corresponding PCC rule, and receiving the PCC decision providing response message sent by the source network access gateway;

the network anchor point comprises a PCEF, receives a resource release message sent by a source network access gateway, releases related resources of a source network, receives a charging rule issued by a PCRF and charges;

the source network access gateway is connected with the network anchor point based on a mobile IP protocol, comprises a PCEF (policy and charging enforcement function) used for carrying out IP-CAN (Internet protocol-controller area network) bearing control on a source network, receives a PCC (policy and charging control) decision providing message sent by the PCRF, triggers the PCEF to release corresponding bearing and related resources in the source network, sends a PCC decision providing response message to the PCRF, and sends a resource release message to the network anchor point.

It can be seen from the above technical solutions that, in the method and system for releasing source network resources in an evolved network handover process according to the embodiments of the present invention, during or after establishment of a Target network bearer, a PCRF controls release of the source network resources synchronously or asynchronously, during release of the synchronous control source network resources of the PCRF, a network anchor or a Target network access gateway sends a request to the PCRF to request generation of a new PCCRule to a Target AGW, and after the Target AGW completes establishment of the Target network bearer, sends a message to notify the PCRF to trigger the PCRF to initiate a process of releasing the source network bearer; the method comprises the steps of asynchronously establishing a Target Network bearer and releasing a Source Network resource, namely after receiving an IP Access Network Session (IP-CAN Session) establishment message sent by a Target AGW or a Network Anchor point, a PCRF sends a PCC decision to provide a message to a Source AGW to request to release the bearer and related resources of the Source Network, and CAN trigger a PCRF asynchronous control bearer release process through the Target AGW or the Network Anchor, wherein the PCRF asynchronous control bearer release process CAN be based on the switching from a 3GPP to a non-3GPP Network or based on the switching from the non-3GPP to the 3GPP Network, so that after a terminal switches a Target Network from the Source Network, the release of the Source Network bearer resource CAN be timely performed, the use efficiency of the Source Network bearer resource is improved, and the waste of the resource is reduced.

Drawings

Fig. 1 is a schematic diagram of a non-roaming architecture of a conventional EPS network;

fig. 2 is a schematic diagram of a roaming architecture of a conventional EPS network;

FIG. 3 is a schematic diagram of a conventional WLAN-based interconnection system architecture;

fig. 4 is a schematic diagram illustrating a handover procedure between a legacy S2a and S5 interface based on PMIPv6 in a non-roaming scenario and a trusted non-3GPP interface;

fig. 5 is a schematic diagram of a system structure for releasing source network resources in an evolved network handover process according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of another system for releasing source network resources in an evolved network handover process according to an embodiment of the present invention;

fig. 7 is a schematic view of a bearer release flow under PCRF synchronous control in an embodiment of the present invention;

fig. 8 is a schematic view of a bearer release flow of triggering PCRF asynchronous control by Target AGW in an embodiment of the present invention;

fig. 9 is a schematic view of a bearer release flow of a target Network Anchor triggering PCRF asynchronous control in the embodiment of the present invention;

fig. 10 is a schematic flowchart of bearer establishment and release in a process of switching from a 3GPP network to a non-3GPP network under synchronous control of a PCRF in an embodiment of the present invention;

fig. 11 is a schematic flowchart of bearer establishment and release in a handover process from a 3GPP to a non-3GPP network, where the PCRF is asynchronously controlled and triggered by a non-3GPP AGW in an embodiment of the present invention;

fig. 12 is a schematic flow chart of bearer establishment and release in a handover process from a 3GPP to a non-3GPP Network, where the PCRF is asynchronously controlled and triggered by a third non-3GPP Network Anchor in the embodiment of the present invention;

fig. 13 is a schematic flowchart of bearer establishment and release in a handover process from 3GPP to non-3GPP network under PCRF synchronous control triggered by PMIPv6 in the non-3GPP according to the embodiment of the present invention;

fig. 14 is a schematic flow diagram of a handover from PMIPv6 to a 3GPP network by non-3GPP in an embodiment of the present invention, where the PCRF triggered by the 3GPP gw asynchronously controls establishment and release of a non-3GPP network bearer;

fig. 15 is a flowchart illustrating a procedure of a non-3GPP Network bearer establishment and release asynchronously controlled by a PCRF triggered by a Network Anchor in a handover from PMIPv6 to a 3GPP Network according to the sixth embodiment of the present invention;

fig. 16 is a schematic flow chart of a handover from a seventh non-3GPP to a 3GPP network based on a CMIPv4FA mode, where the PCRF synchronously controls establishment and release of a non-3GPP network bearer according to the embodiment of the present invention;

fig. 17 is a flowchart illustrating a handover of the eighth non-3GPP to the 3GPP network based on the CMIPv4FA mode, where the PCRF triggered by the 3GPP gw asynchronously controls establishment and release of the bearer in the non-3GPP network;

fig. 18 is a flow diagram illustrating a process of a non-3GPP Network bearer establishment and release synchronously controlled by a PCRF triggered by a 3GPP Network Anchor in handover from a CMIPv4FA mode to a 3GPP Network according to the ninth embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and examples.

In the embodiment of the invention, the PCRF synchronously or asynchronously controls the release of the source network resources during or after the establishment of the target network bearer, so that the release of the source network bearer resources can be timely carried out after the terminal switches the target network from the source network.

In order to achieve the above object, an embodiment of the present invention provides a system for releasing source network resources in an evolved network handover process.

Fig. 5 is a schematic diagram of a system structure for releasing source network resources in an evolved network handover process according to an embodiment of the present invention. Referring to fig. 5, the system comprises: a target AGW (target AGW)51, a PCRF52, a Network Anchor (Network Anchor)53, and a source AGW (Source AGW)54, wherein,

the Target AGW51 is used for the PCEF on the terminal to send an IP-CAN Session establishment indication message to the PCRF52 after the terminal and the network establish connection; receiving an IP-CAN Session establishment response message, initiating the establishment of an IP-CAN Bearer of a target network according to PCC Rule information carried by the received IP-CAN Session establishment response message, and sending an IP-CAN Session establishment completion response message to a PCRF 52;

the PCRF52 is used for receiving the IP-CAN Session establishment indication message output by the Target AGW51, generating corresponding PCC Rule information, carrying the PCC Rule information in the IP-CAN Session establishment response message and sending the PCC Rule information to the Target AGW 51; receiving an IP-CAN Session establishment completion response message sent by Target AGW51, issuing a PCC decision providing message to a Network Anchor53, and requesting the Network Anchor53 to delete a corresponding PCC Rule; receiving a PCC decision providing response message sent by a Network Anchor53, and knowing that the Anchor53 deletes the corresponding PCC Rule;

a Network Anchor53, which includes a PCEF (logical function entity) of a Source Network, and is used for policy and charging control, receiving a PCC decision providing message issued by PCRF52, triggering the PCEF logical function entity to send a resource release message to Source AGW54, and sending a PCC decision providing response message to PCRF 52;

the Source AGW54 is connected to the Network Anchor53 based on a GPRS Tunneling Protocol (GTP), receives a resource release message sent by the Network Anchor53, and releases a corresponding bearer and related resources in the Source Network.

The flow of fig. 5 includes two interaction modes, a synchronous interaction mode and an asynchronous interaction mode, where the synchronous interaction mode can be described as follows: after the terminal and the Network are connected, the PCEF on Target AGW51 sends an IP-CAN Session establishment indication message to PCRF52, PCRF52 receives the IP-CAN Session establishment indication message, generates corresponding PCC Rule information, carries the PCC Rule information in an IP-CAN Session establishment response message, sends to Target AGW51, Target AGW51 receives the IP-CAN Session establishment response message, initiates the IP-CAN Bearer establishment of the Target Network according to the Rule information carried by the received IP-CAN Session establishment response message, sends an IP-CAN Session establishment completion response message to PCRF52 after establishment, PCRF52 receives the IP-CAN Session establishment completion response message, issues a PCC decision providing message to Network Anchor53, requests Network Anchor53 to delete the corresponding PCC Rule, Network Anchor53 decides to receive the PCC delivered by PCRF52 to provide a PCC message, triggers a PCEF logic entity to send a Source 54, the source agw54 receives a resource release message sent by the Network Anchor53, and after releasing a corresponding bearer and related resources in the source Network, sends a feedback message to the Network Anchor53, the Network Anchor53 deletes a corresponding PCC Rule, and sends a PCC decision provision response message to the PCRF52, and the PCRF52 receives the PCC decision provision response message to know that the Anchor53 has deleted the corresponding PCC Rule.

The asynchronous interaction mode is described as follows, a PCEF on a Target AGW51 sends an IP-CAN Session establishment indication message to a PCRF52, the PCRF52 receives the IP-CAN Session establishment indication message, generates corresponding PCC Rule information, is carried in an IP-CAN Session establishment response message and sent to the Target AGW51, the Target AGW51 receives the IP-CAN Session establishment response message, initiates the IP-CAN Bearer establishment of a Target network according to the PCC Rule information carried by the received IP-CAN Session establishment response message, and sends an IP-CAN Session establishment completion response message to the PCRF52 after the establishment; when PCRF52 receives the IP-CAN Session establishment indication message, PCRF52 issues a PCC decision providing message to Network Anchor53, requests Network Anchor53 to delete the corresponding PCC Rule, Network Anchor53 receives the PCC decision providing message, initiates a source Network release flow to release a source Network bearer and related resources, deletes the corresponding PCC Rule, after resource release is completed, sends a PCC decision providing response message to PCRF52, PCRF52 receives the PCC decision providing response message, and learns that Network Anchor53 deletes the corresponding PCC Rule.

In practical application, the Source AGW54 may also be connected to the Network Anchor53 based on other protocols, where the Network Anchor may be a PDN Gateway or an HA.

Fig. 6 is a schematic structural diagram of another system for releasing source network resources in an evolved network handover process according to an embodiment of the present invention. Referring to fig. 6, the system comprises: target AGW61, PCRF62, NetworkAnchor63 and Source AGW64, wherein,

the Target AGW61 is used for the PCEF on the terminal to send an IP-CAN Session establishment indication message to the PCRF62 after the terminal and the network establish connection; receiving an IP-CAN Session establishment response message, initiating the establishment of an IP-CAN Bearer of a target network according to PCC Rule information carried by the received IP-CAN Session establishment response message, and sending an IP-CAN Session establishment completion response message to a PCRF 62;

the PCRF62 is used for issuing charging rules to the Network Anchor63, receiving an IP-CAN Session establishment indication message output by the Target AGW61, generating corresponding PCC Rule information, carrying the PCC Rule information in an IP-CAN Session establishment response message and sending the PCC Rule information to the Target AGW 61; receiving an IP-CAN Session establishment completion response message sent by Target AGW61, issuing a PCC decision providing message to a Source AGW64, and requesting the Source AGW64 to delete the corresponding PCC Rule; receiving a PCC decision providing response message sent by Source AGW64, and knowing that Source AGW64 deletes the corresponding PCCRule;

the Network Anchor63 comprises a PCEF logic function entity, receives the resource release message sent by the Source AGW64, releases the related resources of the Source Network, receives the charging rule sent by the PCRF62 and charges;

source AGW64, connected to Network Anchor63 based on MIP, includes a PCEF logic function entity (not shown in the figure) that performs IP-CAN bearer control by a Source Network, receives a PCC decision provision message issued by PCRF62, triggers the PCEF logic function entity, releases a corresponding bearer and related resources in the Source Network, sends a PCC decision provision response message to PCRF62, and sends a resource release message to Network Anchor 63.

The flow of fig. 6 includes two interaction modes, a synchronous interaction mode and an asynchronous interaction mode, where the synchronous interaction mode can be described as follows: after the terminal and the network are connected, PCRF62 issues charging rules to network Anchor63, Source AGW64 receives the charging rules issued by PCRF62 for charging, PCEF on Target AGW61 sends IP-CAN Session establishment indication message to PCRF62, PCRF62 receives IP-CAN Session establishment indication message, generates corresponding PCC Rule information, carries the PCC Rule information in IP-CAN Session establishment response message and sends the IP-CAN Session establishment response message to Target AGW61, TargetGW 61 receives IP-CAN Session establishment response message, PCC Rule information carried in the received IP-CAN Session establishment response message initiates IP-CAN Bearer establishment of the Target network, after establishment, sends IP-CAN Session establishment completion response message to PCRF62, 62 receives PCC-CAN Session establishment completion response message, issues PCC Rule AGW64 for providing response message to Source AGW 733, requires PCRF to delete corresponding PCC Rule AGW64, PCRF 3884 for providing PCC rules, triggering a Source network release flow through a PCEF logic function entity to release a Source network bearer and related resources, deleting corresponding PCC Rule, after resource release is completed, sending a PCC decision providing response message to a PCRF62, and receiving the PCC decision providing response message by a PCRF62 to know that the Source AGW64 deletes the corresponding PCC Rule.

The asynchronous interaction mode is described as follows: a PCEF on a Target AGW61 sends an IP-CAN Session establishment indication message to a PCRF62, the PCRF62 receives the IP-CAN Session establishment indication message, the PCRF62 receives the IP-CAN Session establishment indication message, generates corresponding PCC Rule information, carries the PCC Rule information in an IP-CAN Session establishment response message, sends the PCC Rule information to a Target AGW61, a targetAGW61 receives the IP-CAN Session establishment response message, initiates the IP-CAN Bearer establishment of a Target network according to the PCC Rule information carried by the received IP-CAN Session establishment response message, and sends an IP-CAN Session establishment completion response message to a PCRF52 after the establishment; when PCRF52 receives the IP-CAN Session establishment indication message, PCRF52 issues a PCC decision providing message to Source AGW64, requests Source AGW64 to delete the corresponding PCC Rule, Source AGW64 receives the PCC decision providing message, initiates a Source network release flow to release the Source network bearer and the related resource, deletes the corresponding PCC Rule, after the resource release is completed, sends a PCC decision providing response message to PCRF62, and PCRF62 receives the PCC decision providing response message to know that Source AGW64 deletes the corresponding PCC Rule.

In practical application, the Source AGW64 can also be connected with the Network Anchor63 based on other protocols.

Based on fig. 5 and 6, the embodiment of the invention includes two technical solutions.

The first set of technical scheme: the bearer establishment procedure of the target network and the bearer release procedure of the source network are synchronous procedures. That is, after receiving the response message of completing the establishment of the IP-CAN Session sent by the target network, the PCRF sends a PCC decision providing message to the Source AGW, and requests to release the corresponding bearer and the related resources.

Fig. 7 is a schematic view of a bearer release flow under PCRF synchronous control in an embodiment of the present invention. Referring to fig. 7, the process includes:

step 701, a terminal establishes connection with a source network;

in this step, after the terminal establishes connection with the source network, the uplink and downlink data are transmitted through the source network.

Step 702, a terminal discovers a target network and accesses the target network;

step 703, the terminal establishes connection with a Network Anchor of the Target Network through a Target AGW;

step 704, Target AGW sends IP-CAN Session establishment indication message to PCRF, asking for new PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as a user id (user id), a Radio Access Technology Type (RAT Type), a Network anchor IP Address (Network anchor IP Address), a Remote IP Address (Remote IP Address), and a service Access Point domain Name (APN, Access Point Name). The Network Anchor IP Address is an optional parameter, and if the establishment of the IP-CAN Session between the Network Anchor and the PCRF is initiated by the Network Anchor, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CAN Session between the Network Anchor and the PCRF is initiated by the PCRF, the message contains the parameter. The Remote IP Address is a source IP Address of an access service allocated by the Network Anchor to the user, for example, if the access is based on GTP, the source IP Address is PDP Address, and if the access is based on MIP, the source IP Address is HomeAddress.

Step 705, the PCRF receives the IP-CAN Session establishment indication message, associates the new IP-canssesion and the service information, generates corresponding PCC Rule information, carries the PCC Rule information in the IP-CAN Session establishment response message, and sends the PCC Rule information to the PCEF on the Target AGW;

step 706, the PCEF on the Target AGW establishes PCC Rule information carried by the response message according to the IP-CAN Session issued by the PCRF, and initiates an IP-CAN Bearer establishment procedure with the terminal;

step 707, after the Target network completes the establishment of the IP-CAN Bearer, the Target AGW sends an IP-CAN Session establishment completion response message to the PCRF, and notifies the PCRF that the Target network completes the establishment of the corresponding Bearer;

in this step, after receiving the response message of completing establishment of the IP-CAN Session, the PCRF is based on the MIP or GTP technology between the Source AGW and the Network Anchor, and thus, the flows of releasing the bearer resource of the Source Network are also different, if the Source AGW and the Network Anchor are based on the MIP, the steps 708a to 710a are executed, otherwise, the steps 708b to 710b are executed.

Step 708a, after the PCRF confirms that the target network completes the establishment of the corresponding bearer, the PCRF issues a PCC decision providing message to the Source AGW, and requests the PCEF on the Source AGW to delete the corresponding pcresults;

step 709a, the Source AGW initiates a release process of the bearer and the related resource, and releases the corresponding bearer and the related resource in the Source network;

in this step, if the terminal has a dual radio capability, the terminal participates in the release process of the bearer and the related resources of the source network, which is indicated by a dotted line in the figure.

Step 710a, after completing bearer and resource release, the Source AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the corresponding PCC Rule deletion has been completed.

Step 708b, after confirming that the target Network completes the establishment of the corresponding bearer, the PCRF issues a PCC decision providing message to the Network Anchor, and requests the PCEF on the Network Anchor to delete the corresponding PCC Rule;

step 709b, the Network Anchor initiates a release flow of the bearer and the related resources, and releases the corresponding bearer and the related resources in the source Network;

in this step, if the terminal has a bidirectional radio reception (dual radio) capability, the terminal participates in the release process of the bearer and related resources of the source network, which is indicated by a dotted line in the figure.

Step 710b, after completing the bearer and resource release, the Network Anchor sends a PCC decision to provide a response message to the PCRF, notifying the PCRF that the corresponding PCC Rule deletion has been completed.

For the establishment process of the Target Network bearer, the establishment process CAN also be initiated by a Network Anchor, an IP-CAN Session establishment indication message containing information of corresponding parameters such as User ID, APN, RAT Type, Target AGW IP Address and RemoteIP Address is sent to PCRF, PCRF then generates corresponding PCC Rule issue (PUSH) to Target AGW, and the bearer of the Target Network is established. After finishing the establishment of the bearer, the Target AGW sends a response message to the PCRF again to inform the PCRF of the completion of the establishment of the bearer, and the PCRF then initiates a bearer release process to the source network. In this process, Target AGWIP Address is an optional parameter.

The second technical proposal is as follows: the bearer establishment procedure of the target network and the bearer release procedure of the source network are asynchronously performed procedures. That is, after receiving the IP-CAN Session establishment indication message sent by the Target AGW, the PCRF may send a PCC decision provisioning message to the Source AGW, and request to release the corresponding bearer and the related resources.

The method comprises two ways according to different entities triggering the PCRF to initiate the release process:

1. target AGW triggers load release of PCRF asynchronous control

Fig. 8 is a schematic view of a bearer release flow of triggering PCRF asynchronous control by Target AGW in an embodiment of the present invention. Referring to fig. 8, the process includes:

step 801 to step 804, and step 701 to step 704, which are not described herein again;

step 805, the PCRF receives the IP-CAN Session establishment indication message, associates the new IP-CAN Session and the service information, generates a corresponding PCC Rule, carries the PCC Rule in the IP-CAN Session establishment response message, and sends the PCC Rule to the PCEF on the Target AGW;

in the step, after receiving the IP-CAN Session establishment indication message, the PCRF performs steps 806a to 808a if the Source AGW and the Network Anchor are based on the MIP or GTP technology, and performs steps 806b to 808b if the Source AGW and the Network Anchor are based on the MIP.

Step 806a, the PCRF receives the IP-CAN Session establishment indication message, issues a PCC decision providing message to the Source AGW, and requests the PCEF of the Source AGW to delete the corresponding PCC Rule;

step 807a, Source AGW initiates a release flow of bearer and related resources to release the corresponding bearer and related resources in the Source network;

Step 808a, after completing the bearer and resource release, the Source AGW sends a PCC decision to provide a response message to the PCRF, and notifies the corresponding PCC Rule that the deletion has been completed.

Step 806b, the PCRF receives the IP-CAN Session establishment indication message, issues a PCC decision providing message to the Network Anchor, and requests the PCEF on the Network Anchor to delete the corresponding PCC Rule;

step 807b, the Network Anchor initiates a release flow of the bearer and the related resources, and releases the corresponding bearer and the related resources in the source Network;

Step 808b, after completing the bearer and resource release, the Network Anchor sends a PCC decision to provide a response message to the PCRF, and notifies the corresponding PCC Rule that the deletion has been completed.

In practical applications, the steps 805 and 806a and the steps 805 and 806b are not strictly time-series relationship, and the steps 806a and 806b may be executed after the step 804.

2. Target Network Anchor triggers PCRF asynchronous control bearer release

Fig. 9 is a schematic view of a bearer release flow for triggering PCRF asynchronous control by a target Network Anchor in the embodiment of the present invention. Referring to fig. 9, the process includes:

step 901 to step 903, and step 801 to step 803 in synchronization, which are not described herein again;

step 904, the target Network Anchor sends an IP-CAN Session establishment indication message to PCRF, requesting a new PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as User ID, APN, RAT Type, Target AGW IP Address, and Remote IP Address). The IP Address of the TargetAGW is an optional parameter, and if the establishment of the IP-CANSession between the TargetAGW and the PCRF is initiated by the TargetAGW, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CAN Session between the Target AGW and the PCRF is initiated by the PCRF, the message contains the parameter. The Remote IP Address is a source IP Address of an access service allocated by the Network Anchor to the user, for example, if the access is based on GTP, the source IP Address is PDP Address, and if the access is based on MIP, the source IP Address is Home Address.

Step 905, the PCRF receives the IP-CAN Session establishment indication message, associates a new IP-CAN Session and service information, generates a corresponding Charging Rule, carries the Charging Rule in the IP-CAN Session establishment response message, and sends the Charg Rule to a PCEF on a target Network Anchor;

step 906, the PCRF receives the IP-CAN Session establishment instruction message, generates a corresponding PCC Rule according to the acquired information, determines to provide a message through the PCC and sends the message to the Target AGW, and the TargetAGW initiates a Target network bearer establishment procedure according to the received PCC Rule;

in the step, after receiving the IP-CAN Session establishment indication message, the PCRF executes steps 907a to 909a if the Source AGW and the Network Anchor are based on MIP or GTP technology, and otherwise executes steps 907b to 909b according to the MIP or GTP technology.

Steps 907a to 909a synchronize steps 806a to 808 a.

Steps 907b to 909b, and steps 806b to 808b are synchronized.

In practical applications, step 905, step 906, and step 907a and step 907b have no strict timing relationship, and step 907a and step 907b may also be executed after step 904.

In summary, for the first set of technical solutions, that is, the bearer establishment process of the target Network and the bearer release process of the Source Network are synchronous processes, two methods for releasing the bearer resources of the Source Network are generated based on whether the MIP technology or the GTP technology exists between the Source AGW and the Network Anchor; for the second technical scheme, namely that the bearer establishment process of the Target Network and the bearer release process of the Source Network are asynchronous processes, the PCRF controls the bearer release of the Source Network based on whether Target AGW or Network Anchor triggers, and each triggering mode can generate two methods for releasing the bearer resources of the Source Network according to whether MIP technology or GTP technology exists between Source AGW and Network Anchor.

Based on fig. 5 to fig. 9, nine embodiments are described below in detail for a specific implementation of the present invention used in a system for releasing source network resources in an evolved network handover process.

In the embodiment of the invention, the non-3GPP AGW can be an access gateway entity of an untrusted non-3GPP ePDG or a trusted non-3GPP, such as an ASN GW in WiMAX access; and in the synchronous control process of the PCRF, the Target Network sends an IP-CAN Session establishment indication message to the PCRF by the Network Anchor to request to generate a new PCC Rule, and sends the PCC Rule to the Target AGW, and after the Target AGW completes the establishment of the Target Network bearer, the Target AGW sends an IP-CAN Session establishment completion response message to inform the PCRF, and triggers the PCRF to initiate the release of the source Network bearer.

Embodiments one to three described below are based on handover from 3GPP to a non-3GPP network.

The first embodiment is as follows:

fig. 10 is a schematic flowchart of bearer establishment and release in a handover process from 3GPP to non-3GPP network under synchronous control of PCRF in an embodiment of the present invention. Referring to fig. 10, a 3GPP network may access based on GTP or MIP, and the procedure includes:

1001, a terminal establishes connection with a 3GPP network;

in this step, after the terminal establishes a connection with the 3GPP Network, an uplink Packet Data Unit (PDU, Packet Data Unit) is transmitted between the terminal and the Network Anchor through the 3GPP Network.

Step 1002, the terminal finds a non-3GPP network and accesses the non-3GPP network;

step 1003, the terminal establishes connection with a Non-3GPP Network access gateway (Non-3GPP AGW) and establishes an MIP tunnel between Network anchors;

in this step, after the terminal establishes connection with the Non-3GPP AGW and the Network Address, the Non-3GPP AGW may obtain information such as the Home Address (Home Address) and the Network Address IP Address of the terminal.

Step 1004, the Non-3GPP AGW sends an IP-CAN Session establishment indication message to the PCRF, and acquires a corresponding PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as User-ID, Home Address, HA Address, APN, RAT Type, and the like. The RAT Type is used for identifying the Type of the current access network; HA Address is an optional parameter, if the establishment of the IP-CAN Session between the Network Anchor and the PCRF is initiated by the Network Anchor, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CANSession between the Network Anchor and the PCRF is initiated by the PCRF, the message contains the parameter.

Step 1005, PCRF according to the received IP-CAN Session establishment indication message, generates a corresponding PCC Rule carried in the IP-CAN Session establishment response message, and issues to Non-3 GPPAGW;

step 1006, the Non-3GPP AGW establishes a corresponding IP-CAN Bearer in the Non-3GPP network according to the received PCC Rule;

step 1007, after completing the establishment of the IP-CAN Bearer in the Non-3GPP network, the Non-3GPP gw sends an IP-CAN Session establishment completion response message to the PCRF, notifying the PCRF that the establishment of the corresponding IP-CAN Bearer is completed;

in practical application, after receiving the IP-CAN Session establishment indication message, the PCRF performs steps 1008a to 1012a if the Source AGW and the Network Anchor are based on the MIP or GTP technology, and performs steps 1008b to 1010b if the Source AGW and the Network Anchor are based on the MIP.

Step 1008a, after the PCRF determines that the corresponding bearer in the non-3GPP network is established, the PCRF sends a PCC decision providing message to the 3GPP AGW, and requests the PCEF on the 3GPP AGW to delete the corresponding pcresult;

step 1009a, the 3GPP AGW sends a proxy binding update message to the Network Anchor, and deletes the corresponding proxy binding on the Network Anchor based on Care-of Address (COA);

in this step, the proxy binding update message includes a User-ID and a life cycle (lifetime) parameter, where the value of lifetime is set to 0.

Step 1010a, the Network Anchor returns an agent binding response message to the 3GPP AGW;

in this step, if there is no corresponding agent binding of the COA in the Network Anchor, the Network Anchor sets the processing state of the agent binding update message to 133 in the agent binding response message, and notifies the 3GPP AGW, that is, it indicates that the Network Anchor is not the HA of the user.

Step 1011a, the 3GPP AGW releases the IP-CAN Bearer in the 3GPP network according to the PCC Rule to be deleted;

in this step, if the terminal has dual radio capability, the terminal participates in the process of releasing the bearer and related resources of the 3GPP network, which is indicated by a dotted line in the figure.

Step 1012a, after completing the release of the IP-CAN Bearer of the 3GPP network, the 3GPP AGW sends a response message to the PCRF to notify the PCRF that the PCC Rule corresponding to the PCRF has been deleted.

Step 1008b, after the PCRF determines that the corresponding bearer in the non-3GPP Network is established, the PCRF sends a PCC decision providing message to the Network Anchor, and requests the PCEF on the Network Anchor to delete the corresponding PCC Rule;

step 1009b, the Network Anchor releases the IP-CAN Bearer in the 3GPP Network according to the PCC Rule to be deleted;

Step 1010b, after the release of the 3GPP Network IP-CAN Bearer is completed, the Network Anchor sends a response message to the PCRF to provide the PCC Rule, and notifies the PCRF that the PCC Rule corresponding to the PCRF has been deleted.

Example two:

in the first embodiment, the bearer establishment procedure of the target network and the bearer release procedure of the source network are synchronous procedures, and in practical application, the bearer establishment procedure of the target network and the bearer release procedure of the source network may also be asynchronous procedures.

Fig. 11 is a schematic flowchart of bearer establishment and release in a handover process from a 3GPP to a non-3GPP network, where the PCRF is asynchronously controlled and triggered by a non-3GPP AGW in an embodiment of the present invention. Referring to fig. 11, the 3GPP network may access based on GTP or MIP, and the procedure includes:

step 1101 to step 1104, and synchronization step 1001 to step 1004;

step 1105, PCRF according to the received IP-CAN Session establishment indication message, generates corresponding PCC Rule carried in the IP-CAN Session establishment response message, and issues to Non-3 GPPAGW;

in this step, after receiving the IP-CAN Session establishment indication message, the PCRF performs steps 1106a to 1110a if the Source AGW and the Network Anchor are based on the MIP or GTP technology, and otherwise performs steps 1106b to 1108b, according to the MIP or GTP technology between the Source AGW and the Network Anchor.

Step 1106a, the PCRF, according to the received IP-CAN Session establishment indication message, sends a PCC decision providing message to the 3GPP AGW, and requests the PCEF on the 3GPP AGW to delete the corresponding PCC Rule;

step 1107a, the 3GPP AGW sends an agent binding update message to the Network Anchor, and deletes the corresponding agent binding on the Network Anchor based on Care-of Address (COA);

in this step, the proxy binding update message includes a User-ID and a lifetime parameter, where the value of lifetime is set to 0.

Step 1108a, the Network Anchor returns an agent binding response message to the 3GPP AGW;

Step 1109a, the 3GPP AGW releases the IP-CAN Bearer in the 3GPP network according to the PCC Rule deleted by the PCRF;

Step 1110a, after the release of the IP-CAN Bearer of the 3GPP network is completed, the 3GPP AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the PCC Rule deletion corresponding to the PCRF is completed.

Step 1106b, the PCRF establishes an indication message according to the received IP-CAN Session, and sends a PCC decision providing message to the Network Anchor, requesting the PCEF on the Network Anchor to delete the corresponding PCC Rule;

step 1107b, the Network Anchor releases the IP-CAN Bearer in the 3GPP Network according to the PCC Rule deleted by the PCRF;

Step 1108b, after the release of the 3GPP Network IP-CAN Bearer is completed, the Network Anchor sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the PCC Rule deletion corresponding to the PCRF is completed.

In practical applications, the steps 1105 and 1106a and the steps 1105 and 1106b have no strict timing relationship, and the steps 1106a and 1106b may be executed after the step 1104.

Example three:

fig. 12 is a schematic flowchart of bearer establishment and release in a handover process from a 3GPP to a non-3GPP Network, where the PCRF is asynchronously controlled and triggered by a third non-3GPP Network Anchor in the embodiment of the present invention. Referring to fig. 12, a 3GPP network may access based on GTP or MIP, and the procedure includes:

step 1201 to step 1203, synchronization step 1101 to step 1103;

step 1204, the non-3GPP Network Anchor sends an IP-CAN Session establishment instruction message to the PCRF, requiring generation of a corresponding PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as User-ID, Home Address, Non-3GPP AGW IP Address, APN, RAT Type, and the like. The RAT Type is used for identifying the Type of a current access network, AGW IP Address is an optional parameter, and if the establishment of the IP-CAN Session between the Non-3GPPAGW and the PCRF is initiated by the AGW, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CAN Session between the AGW and the PCRF is initiated by the PCRF, the message contains the parameter.

Step 1205, the PCRF generates a corresponding Charging Rule according to the received IP-CAN Session establishment indication message, carries the Charging Rule in the IP-CAN Session establishment response message, and issues the Charging Rule to a non-3GPP network Anchor;

step 1206, the PCRF generates a corresponding PCC Rule according to the received IP-CAN Session establishment instruction message, determines to provide a message through the PCC and sends the message to the Non-3GPP AGW, and the Non-3GPP PAGW establishes an IP-CAN Bearer of the Non-3GPP network according to the received PCC Rule;

in practical application, after receiving the IP-CAN Session establishment indication message, the PCRF performs steps 1207a to 1211a if the Source AGW and the Network Anchor are based on the MIP or GTP technology, and performs steps 1207b to 1209b if the Source AGW and the Network Anchor are based on the MIP.

Steps 1207a to 1211a, synchronize steps 1106a to 1110 a.

Steps 1207b to 1209b, and synchronization steps 1106b to 1108 b.

In practical applications, step 1205, step 1206, step 1207a and step 1207b have no strict timing relationship, and step 1207a and step 1207b may be executed after step 1204.

Embodiments four to nine described below are handover based on non-3GPP to 3GPP network, where embodiments four to six are handover procedures of non-3GPP based on PMIPv6 to 3GPP network, and embodiments seven to nine are handover procedures of non-3GPP based on CMIPv4FA mode to 3GPP network.

Example four:

fig. 13 is a flowchart illustrating bearer establishment and release in a handover process from a 3GPP to a non-3GPP network based on PMIPv6 triggered PCRF synchronous control by a non-3GPP according to the embodiment of the present invention. Referring to fig. 13, the process includes:

step 1301, the terminal establishes connection with a non-3GPP network;

in this step, after the terminal establishes a connection with the Non-3GPP Network, the uplink PDU and the downlink PDU are transmitted between the terminal and the Network Anchor through the Non-3GPP Network, and an MIP tunnel is established between the Non-3GPP AGW and the Network Anchor based on PMIPv 6.

Step 1302, the terminal discovers a 3GPP network and successfully accesses the 3GPP network;

step 1303, the terminal establishes connection with the 3GPP AGW;

in this step, if the 3GPP access is based on GTP, the 3GPP AGW where the PCEF is located is integrated with the Network Anchor; if the 3GPP access is based on IETF Variant (PMIPv6), the 3GPP PAWW establishes a MIP tunnel to the Network Anchor based on PMIPv 6. After the terminal establishes connection with the 3GPP AGW, the 3GPP AGW acquires information such as an IP address of a Network Anchor, a remote address of the terminal and the like.

In step 1304, the 3GPP AGW sends an IP-CAN Session establishment instruction message to the PCRF to obtain the corresponding PCC Rule.

In this step, the IP-CAN Session establishment indication message includes parameter information such as User-ID, Remote IP Address, Network Anchor IP Address, APN, RAT Type, and the like. The RAT Type is used for identifying the Type of the current access network; the Network Anchor IP Address is an optional parameter, and if the establishment of the IP-CAN Session between the Network Anchor and the PCRF is initiated by the Network Anchor, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CAN Session between the network Anchor and the PCRF is initiated by the PCRF, the message contains the parameter; the Remote IP Address is a source IP Address of an access service allocated by the Network Anchor for the user, for example, if the access is based on GTP, the source IP Address is PDP Address, and if the access is based on MIP, the source IP Address is Home Address.

Step 1305, the PCRF generates a corresponding PCC Rule according to the received IP-CAN Session establishment indication message, and establishes a response message through the IP-CAN Session and sends the response message to the 3GPP AGW;

step 1306, the 3GPP AGW establishes a corresponding IP-CAN Bearer in the 3GPP network according to the received PCC Rule;

step 1307, after completing the establishment of the IP-CAN Bearer in the 3GPP network, the 3GPP AGW sends an IP-CAN establishment completion response message to the PCRF, and notifies the PCRF that the establishment of the IP-CAN Bearer corresponding to the PCRF is completed.

Step 1308, after the PCRF determines that the establishment of the corresponding bearer in the 3GPP network is completed, the PCRF sends a PCC decision providing message to the Non-3GPP AGW, and requests the PCEF on the Non-3GPP AGW to delete the corresponding PCC Rule;

step 1309, the Non-3GPP AGW sends an agent binding update message to the Network Anchor, and deletes the corresponding agent binding on the Network Anchor based on the Care-of Address (COA);

Step 1310, the Network Anchor returns an agent binding response message to the Non-3GPP AGW;

in this step, if there is no corresponding agent binding of the COA in the Network Anchor, the Network Anchor sets the processing state of the agent binding update message to 133 in the agent binding response message, and notifies the Non-3GPP AGW, that is, it indicates that the Network Anchor is not the HA of the user.

Step 1311, the Non-3GPP AGW releases the IP-CAN Bearer in the Non-3GPP network according to the PCC Rule required to be deleted by the PCRF;

in this step, if the terminal has dual radio capability, the terminal participates in the release process of the bearer and the related resources of the non-3GPP network, which is indicated by a dotted line in the figure.

Step 1312, after the Non-3GPP network IP-CAN Bearer release is completed, the Non-3GPP AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the release of the PCC Rule corresponding to the PCRF is completed.

Example five:

in the fourth embodiment, the bearer establishment procedure of the target network and the bearer release procedure of the source network are synchronous procedures, and in practical application, the bearer establishment procedure of the target network and the bearer release procedure of the source network may also be asynchronous procedures.

Fig. 14 is a flowchart illustrating a handover of five non-3GPP to a 3GPP network based on PMIPv6, where the PCRF triggered by the 3GPP AGW asynchronously controls establishment and release of a non-3GPP network bearer according to the embodiment of the present invention. Referring to fig. 14, the process includes:

1401 to 1404, and 1201 to 1204, respectively;

step 1405, PCRF according to the received IP-CAN Session establishment instruction message, generates a corresponding PCC Rule, and establishes a response message through IP-CAN Session and sends the response message to 3GPP AGW;

step 1406, the PCRF sends a PCC decision providing message to the Non-3GPP AGW, requesting the PCEF on the Non-3GPP AGW to delete the corresponding PCC Rule;

step 1407, the Non-3GPP AGW sends the proxy binding update to the Network Anchor, and deletes the corresponding proxy binding on the Network Anchor based on the Care-of Address (COA);

Step 1408, the Network Anchor returns an agent binding response message to the Non-3GPP AGW;

Step 1409, the Non-3GPP AGW releases the IP-CAN Bearer in the Non-3GPP network according to the PCC Rule deleted by the PCRF;

Step 1410, after completing the Non-3GPP network IP-CAN Bearer release, the Non-3GPP AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the PCC Rule deletion corresponding to the PCRF is completed.

In practice, step 1405 and step 1406 have no strict timing relationship, and step 1406 may be executed after step 1404.

Example six:

fig. 15 is a flowchart illustrating a procedure of a non-3GPP Network bearer establishment and release asynchronously controlled by a PCRF triggered by a Network Anchor in a handover from PMIPv6 to a 3GPP Network in the sixth embodiment of the present invention. Referring to fig. 15, the process includes:

step 1501 to step 1503, synchronization step 1401 to step 1403;

step 1504, the 3GPP Network Anchor sends an IP-CAN Session establishment indication message to the PCRF, requiring generation of a corresponding PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as User-ID, Remote IPAddress, 3GPP AGW Address, APN, RAT Type, and the like. Wherein, RATType is used for identifying the type of the current access network; 3GPP AGW IP Address is an optional parameter, if the establishment of IP-CAN Session between 3GPP AGW and PCRF is initiated by AGW, the IP-CAN Session establishment indication message does not contain the parameter; if the establishment of the IP-CAN Session between the 3GPP AGW and the PCRF is initiated by the PCRF, the message contains the parameter; the Remote IP Address is a source IP Address of an access service allocated by the Network Anchor for the user, for example, if the access is based on GTP, the source IP Address is PDP Address, and if the access is based on MIP, the source IP Address is Home Address.

Step 1505, PCRF according to received IP-CAN Session set up the instruction message, produce the corresponding charting Rule, set up the response message to issue to 3GPP NetworkAnchor through IP-CAN Session;

step 1506, the PCRF generates a corresponding PCC Rule according to the received IP-CAN Session establishment indication message, determines to provide a message through the PCC and sends the message to the 3GPP AGW, and the 3GPP AGW initiates an establishment flow of the 3GPP network IP-CAN Bearer after receiving the corresponding PCC Rule;

step 1507, the PCRF sends a PCC decision providing message to the Non-3GPP AGW, requesting to release the PCEF on the Non-3GPP AGW to delete the corresponding PCC Rule;

step 1508 to step 1511, and synchronization step 1407 to step 1410.

In practical applications, step 1505, step 1506 and step 1507 do not have strict timing relationship, and step 1507 may be executed after step 1504 or after step 1505; step 1506 may also be performed after step 1504 or after step 1507.

Example seven:

fig. 16 is a flowchart illustrating a procedure in which a PCRF synchronously controls establishment and release of a non-3GPP network bearer in handover from a CMIPv4FA mode to a 3GPP network according to a seventh embodiment of the present invention. Referring to fig. 16, the process includes:

step 1601, the terminal establishes a connection with a non-3GPP network;

in this step, after the terminal establishes a connection with the Non-3GPP Network, the uplink and downlink PDUs are transmitted between the terminal and the Network Anchor through the Non-3GPP Network, and an MIP tunnel, that is, a tunnel between the FA and the HA, is established between the Non-3GPP AGW and the Network Anchor based on CMIPv 4.

Step 1602 to step 1608, and synchronization step 1302 to step 1308;

step 1609, the Non-3GPP AGW sends a registration cancellation message based on CMIPv4 to the Network Anchor, and deletes the corresponding registration based on CMIPv4 on the Network Anchor based on Care-of Address (COA);

in this step, the registration revocation message based on CMIPv4, i.e., the MIPv4registration revocation message, includes a User-ID and a lifetime parameter, where the value of the lifetime is set to 0.

Step 1610, the Network Anchor returns a Registration cancellation response message based on CMIPv4 to the Non-3GPP AGW, namely, an MIPv4Registration acknowledgement message, and informs the Non-3GPP AGW of completion of Registration cancellation;

step 1611, the Non-3GPP AGW releases the IP-CAN Bearer in the Non-3GPP network according to the PCC Rule deleted by the request;

in this step, if the terminal has dual radio capability, the terminal participates in the release process of the bearer and related resources of the Non-3GPP network, which is indicated by a dotted line in the figure, in this process, the Non-3GPP gw may send an Agent Advertisement (Agent Advertisement) to the terminal, and the terminal is notified that the registration of CMIPv4FA has been revoked (sequence number 0).

Step 1612, after the Non-3GPP network IP-CAN Bearer release is completed, the Non-3GPP AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the release of the PCC Rule corresponding to the PCRF is completed.

Example eight:

in the seventh embodiment, the bearer establishment procedure of the target network and the bearer release procedure of the source network are synchronous procedures, and in practical application, the bearer establishment procedure of the target network and the bearer release procedure of the source network may also be asynchronous procedures.

Fig. 17 is a flowchart illustrating a handover of the eighth non-3GPP to the 3GPP network based on the CMIPv4FA mode, where the PCRF triggered by the 3GPP AGW asynchronously controls establishment and release of the non-3GPP network bearer. Referring to fig. 17, the process includes:

step 1701, the terminal establishes connection with the non-3GPP network;

1702-1706, synchronizing 1402-1406;

step 1707, the Non-3GPP AGW sends a registration revocation message based on CMIPv4 to the Network Anchor, and deletes the corresponding registration based on CMIPv4 on the Network Anchor based on Care-of Address (COA);

Step 1708, the Network Anchor returns a CMIPv 4-based Registration cancellation response message to the Non-3GPP AGW, namely a MIPv4Registration acknowledgement message, and informs the Non-3GPP AGW that the Registration cancellation is completed;

step 1709, the Non-3GPP AGW releases the IP-CAN Bearer in the Non-3GPP network according to the PCC Rule deleted by the request;

in this step, if the terminal has dual radio capability, the terminal participates in the release process of the bearer and the related resources of the Non-3GPP network, which is indicated by a dotted line in the figure, in this process, the Non-3GPP gw may send Agent Advertisement (Sequence Number 0) to the terminal, and notify the terminal that the CMIPv4FA registration has been cancelled.

Step 1710, after completing the release of the Non-3GPP network IP-CAN Bearer, the Non-3GPP AGW sends a PCC decision to provide a response message to the PCRF, and notifies the PCRF that the release of the PCC Rule corresponding to the PCRF is completed.

Example nine:

fig. 18 is a flow diagram illustrating a process of a non-3GPP Network bearer establishment and release synchronously controlled by a PCRF triggered by a 3GPP Network Anchor in handover from a CMIPv4FA mode to a 3GPP Network according to the ninth embodiment of the present invention. Referring to fig. 18, the process includes:

step 1801 to step 1803, and synchronization step 1501 to step 1503;

step 1804, the 3GPP Network Anchor sends an IP-CAN Session establishment instruction message to the PCRF, requesting to generate a corresponding PCC Rule;

in this step, the IP-CAN Session establishment indication message includes parameter information such as User-ID, Home Address, HA Address, APN, RAT Type, and the like. Wherein the RAT Type is used to identify the Type of the current access network.

Step 1805, PCRF establishes the instruction message according to IP-CAN Session received, produce the corresponding Charging Rule, set up the response message to issue to 3GPP NetworkAnchor through IP-CAN Session;

step 1806, the PCRF generates a corresponding PCC Rule according to the received IP-CAN Session establishment instruction message, issues the PCC Rule to the 3GPP AGW through the IP-CAN Session establishment instruction, requests the 3GPP AGW to establish an IP-CAN Bearer of the 3GPP network, and establishes Session binding between the PCRF and the 3GPP AGW;

step 1807, the PCRF sends an IP-CAN Session termination indication (User-ID, Remote IP address, APN) message to the Non-3GPP AGW, requesting to release the IP-canbeacon of the Non-3GPP network;

in this step, the IP-CAN Session termination indication message includes parameter information such as User-ID, Remote IPAddress, APN, and the like.

Step 1808 to step 1811, and synchronization step 1107 to step 1110.

In practical applications, step 1805, step 1806 and step 1807 do not have a strict timing relationship, and step 1807 may also be executed after step 1804.

As can be seen from the foregoing embodiments, in the method and system for releasing source network resources in an evolved network handover process according to the embodiments of the present invention, during or after establishment of a Target network bearer, a PCRF controls release of the source network resources synchronously or asynchronously, during release of the synchronous control source network resources of the PCRF, a network anchor or a Target network access gateway sends a request to the PCRF to request generation of a new PCCRule to a Target AGW, and after the Target AGW completes establishment of the Target network bearer, sends a message to notify the PCRF to trigger the PCRF to initiate a process of releasing the source network bearer; the method comprises the steps of asynchronously establishing a Target Network bearer and releasing Source Network resources, namely after receiving an IP-CAN Session establishment message sent by a Target AGW or a Network Anchor point, the PCRF sends a PCC decision to provide a message to a Source AGW to require to release the bearer and related resources of a Source Network, and CAN trigger a PCRF asynchronous control bearer release process through the Target AGW or a Network Anchor, wherein the process CAN be based on switching from a 3GPP to a non-3GPP Network or switching from the non-3GPP to the 3GPP Network, so that after a terminal switches a Target Network from the Source Network, the release of the Source Network bearer resources CAN be timely performed, the use efficiency of the Source Network bearer resources is improved, and the waste of the resources is reduced.

The objects, technical solutions and advantages of the present invention have been described in further detail with reference to the preferred embodiments, it should be understood that the above description is only illustrative of the preferred embodiments of the present invention, and should not be construed as limiting the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for releasing source network resources in an evolved network handover process, the method comprising:

when a terminal is switched to a target network from a source network, after the target network establishes an IP access network session IP-CAN bearer, a Policy and Charging Rules Function (PCRF) entity receives an IP-CAN session establishment completion response message; wherein, the source network is a non-third generation mobile communication standardization partner project 3GPP network, and the target network is a 3GPP network; or, the source network is a 3GPP network, and the target network is a non-3GPP network;

2. The method of claim 1, wherein the step of the target network establishing an IP access network IP-CAN bearer comprises:

the PCRF receives an IP-CAN session establishment indication message sent by a policy and charging enhancement function entity (PCEF) in a target network, generates PCC rule information, carries the PCC rule information in an IP-CAN session establishment response message and sends the PCC rule information to the PCEF on the target network; and the PCEF on the target network establishes the IP-CAN load according to the PCC rule information carried in the IP-CAN session establishment response message issued by the PCRF.

3. The method of claim 2, wherein the IP-CAN session establishment indication message comprises a user ID, a radio access type, a remote IP address, a service access point domain name, or a user ID, a radio access type, a network anchor IP address, a remote IP address, and a service access point domain name.

4. The method of claim 1, wherein the source network is a first communication network and the target network is a second communication network, the first communication network, the terminal establishes IP connectivity to the data gateway through the serving gateway under control of the mobility management entity, the second communication network, the terminal establishes IP connectivity to the data gateway under control of the border access gateway, the border access gateway and the data gateway are connected through a tunnel, or the source network is the second communication network and the target network is the first communication network.

5. The method of claim 4, wherein the source network is a first communication network, the target network is a second communication network, and wherein the PCRF issues a Policy and Charging Control (PCC) decision providing message to a source network access gateway or a network anchor point so that the source network access gateway or the network anchor point releases bearers and related resources in the source network comprises:

after the PCRF determines that the corresponding bearer in the second communication network is established, the PCRF sends a PCC decision providing message to the first communication network access gateway, and carries information for requiring the PCEF on the first communication network access gateway to delete the corresponding PCC rule;

enabling the first communication network access gateway to receive the PCC decision providing message and send an agent binding updating message to the network anchor point;

the network anchor receives the agent binding update message, deletes the corresponding agent binding on the network anchor based on the care-of address and returns an agent binding response message to the first communication network access gateway;

and the first communication network access gateway releases the IP-CAN bearer in the first communication network according to the received PCC rule information required to be deleted by the PCRF.

6. The method of claim 4, wherein the source network is a first communication network, the target network is a second communication network, and wherein the PCRF issues a Policy and Charging Control (PCC) decision providing message to a source network access gateway or a network anchor point so that the source network access gateway or the network anchor point releases bearers and related resources in the source network comprises:

after the PCRF determines that the corresponding bearer in the second communication network is established, the PCRF sends a PCC decision providing message to the network anchor point, and the PCC decision providing message carries information requiring the PCEF on the network anchor point to delete the corresponding PCC rule;

and the network anchor point releases the IP-CAN bearer in the first communication network according to the received PCC rule information required to be deleted by the PCRF.

7. The method of claim 4 wherein the source network is a second communication network, the target network is a first communication network, the second communication network is based on proxy mobile PMIPv6, and the PCRF issues policy and charging control, PCC, decisions to provide a message to a source network access gateway or a network anchor point to cause the source network access gateway or network anchor point to release bearers and related resources in the source network comprises:

after the PCRF determines that the corresponding bearer in the first communication network is established, the PCRF sends a PCC decision providing message to a second communication network access gateway, and carries information for requiring a PCEF on the second communication network access gateway to delete the corresponding PCC rule;

enabling the second communication network access gateway to receive the PCC decision providing message and send an agent binding updating message to the network anchor point;

the network anchor receives the agent binding update message, deletes the corresponding agent binding on the network anchor based on the care-of address and returns an agent binding response message to the second communication network access gateway;

and the second communication network access gateway releases the IP-CAN bearer in the second communication network according to the received PCC rule information required to be deleted by the PCRF.

8. The method of claim 7, wherein the proxy binding update message includes a user ID and a lifecycle parameter with a value set to 0.

9. The method of claim 4 wherein the source network is a second communication network, the target network is a first communication network, the second communication network is based on a client mobile IP foreign agent CMIPv4FA mode, and the PCRF issues a policy and charging control, PCC, decision to provide a message to a source network access gateway or a network anchor point to cause the source network access gateway or the network anchor point to release bearers and related resources in the source network comprises:

so that the second communication network access gateway receives the PCC decision providing message and sends a registration cancellation message based on CMIPv4 to the network anchor point;

the network anchor point receives the registration revocation message, deletes the corresponding registration based on CMIPv4 on the network anchor point based on the care-of address and returns a registration revocation response message based on CMIPv4 to the second communication network access gateway;

and after receiving the registration cancellation response message, the second communication network access gateway releases the IP-CAN bearer in the second communication network according to the received PCC rule information required to be deleted.

10. The method of claim 9, wherein the CMIPv 4-based registration revocation message includes a user ID and a lifecycle parameter with a value set to 0.

11. The method of claim 9, wherein the second communication network access gateway releasing the IP-CAN bearer in the second communication network according to the received PCC rule information requiring deletion further comprises: the second communication network access gateway sends the agent broadcast message to the terminal, the serial number value in the agent broadcast message is set to be 0, and the terminal receives the agent broadcast message and participates in the bearing of the second communication network and the release of related resources.

12. The method of claim 1, further comprising: and after the PCRF receives that the source network completes the bearing and the related resource release in the source network, the source network sends a PCC decision providing response message, and the PCC decision providing response message informs that the corresponding PCC rule is deleted.

13. A method for releasing source network resources in an evolved network handover process, the method comprising:

when a terminal is switched from a source network to a target network, after a Policy and Charging Rules Function (PCRF) receives an IP access network IP-CAN session establishment indication message, the PCRF issues a Policy and Charging Control (PCC) decision to provide a message to an access gateway or a network anchor point of the source network, so that the access gateway or the network anchor point of the source network releases a load and related resources in the source network; wherein, the source network is a non-third generation mobile communication standardization partner project 3GPP network, and the target network is a 3GPP network; or, the source network is a 3GPP network, and the target network is a non-3GPP network.

14. The method of claim 13, wherein the source network is a first communication network, the target network is a second communication network, and wherein the PCRF issues a policy and charging control, PCC, decision to provide a message to an access gateway or a network anchor of the source network, so that the access gateway or the network anchor of the source network releases bearers and related resources in the source network comprises:

the PCRF sends a PCC decision providing message to the first communication network access gateway, and carries information for requiring a policy and charging enhancement function entity (PCEF) on the first communication network access gateway to delete corresponding PCC rules;

and the first communication network access gateway receives the proxy binding response message and releases the IP-CAN bearer in the first communication network according to the received PCC rule information required to be deleted by the PCRF.

15. The method of claim 13, wherein the source network is a first communication network, the target network is a second communication network, and wherein the PCRF issues a policy and charging control, PCC, decision to provide a message to an access gateway or a network anchor of the source network, so that the access gateway or the network anchor of the source network releases bearers and related resources in the source network comprises:

the PCRF sends a PCC decision providing message to the network anchor point, and the PCC decision providing message carries information for requiring the PCEF on the network anchor point to delete the corresponding PCC rule;

and the network anchor point receives the PCC decision providing message and releases the IP-CAN bearer in the first communication network according to the PCC rule information required to be deleted by the PCRF.

16. The method of claim 13, wherein the source network is a second communication network, the target network is a first communication network, the second communication network is based on PMIPv6, and the PCRF issues a policy and charging control, PCC, decision to provide a message to a source network access gateway or a network anchor point, such that the source network access gateway or the network anchor point releases bearers and related resources in the source network comprises:

the PCRF sends a PCC decision providing message to the second communication network access gateway, and carries information for requiring the PCEF on the second communication network access gateway to delete the corresponding PCC rule;

the second communication network access gateway receives the PCC decision providing message and sends an agent binding updating message to the network anchor point;

and the second communication network access gateway receives the proxy binding response message and releases the IP-CAN bearer in the second communication network according to the received PCC rule information required to be deleted by the PCRF.

17. The method of claim 14 or 16, wherein the proxy binding update message contains a user ID and a lifecycle parameter with a value set to 0.

18. The method of claim 13, wherein the source network is a second communication network, the target network is a first communication network, the second communication network is based on a CMIPv4FA mode, and the PCRF issues a policy and charging control, PCC, decision to provide a message to a source network access gateway or a network anchor point, such that the source network access gateway or the network anchor point releases bearers and related resources in the source network comprises:

the PCRF sends a PCC decision providing message to the second communication network access gateway and requires the PCEF on the second communication network access gateway to delete the corresponding PCC rule;

enabling the second communication network access gateway to receive the PCC decision providing message and send a registration cancellation message based on CMIPv4 to the network anchor point;

and the second communication network access gateway releases the IP-CAN bearer in the second communication network according to the PCC rule deleted by the request.

19. The method of claim 18, wherein the step of releasing the IP-CAN bearer in the second communication network further comprises: the second communication network access gateway sends the agent broadcast message to the terminal, the serial number value in the agent broadcast message is set to be 0, and the terminal receives the agent broadcast message and participates in the bearing of the second communication network and the release of related resources.

20. A system for releasing source network resources during an evolved network handover, the system comprising: the system comprises a target network access gateway, a Policy and Charging Rules Function (PCRF), a network anchor point and a source network access gateway, wherein the source network is a non-third-generation mobile communication standardization partner project (3 GPP) network, and the target network is a 3GPP network; or, the source network is a 3GPP network, and the target network is a non-3GPP network; wherein,

the target network access gateway is used for sending an IP access network IP-CAN session establishment indication message to the PCRF after the connection between the terminal and the network is established, receiving an IP-CAN session establishment response message, initiating IP-CAN bearer establishment of the target network according to Policy and Charging Control (PCC) rule information carried by the received IP-CAN session establishment response message, and sending an IP-CAN session establishment completion response message to the PCRF;

the PCRF is configured to receive an IP-CAN session establishment indication message output by the target network access gateway, generate corresponding PCC rule information, carry the PCC rule information in an IP-CAN session establishment response message, send the IP-CAN session establishment response message to the target network access gateway, receive an IP-CAN session establishment completion response message sent by the target network access gateway, issue a PCC decision provision message to the network anchor, carry a request for the network anchor to delete the corresponding PCC rule information, and receive the PCC decision provision response message sent by the network anchor;

the network anchor point comprises a policy and charging enhancement function entity (PCEF) used by a source network for policy and charging control, receives the PCC decision providing message issued by the PCRF, triggers the PCEF to send a resource release message to the source network access gateway, and sends a PCC decision providing response message to the PCRF;

the source network access gateway is connected with the network anchor point based on a GPRS tunnel protocol, receives a resource release message sent by the network anchor point and releases corresponding load and related resources in a source network.

21. A system for releasing source network resources during an evolved network handover, the system comprising: the system comprises a target network access gateway, a Policy and Charging Rules Function (PCRF), a network anchor point and a source network access gateway, wherein the source network is a non-third-generation mobile communication standardization partner project (3 GPP) network, and the target network is a 3GPP network; or, the source network is a 3GPP network, and the target network is a non-3GPP network; wherein,

the PCRF is configured to issue a charging rule to the network anchor, receive the IP-CAN session establishment indication message output by the target network access gateway, generate corresponding PCC rule information, carry the PCC rule information in the IP-CAN session establishment response message, send the IP-CAN session establishment response message to the target network access gateway, receive the IP-CAN session establishment completion response message sent by the target network access gateway, issue a PCC decision provision message to the source network access gateway, request the source network access gateway to delete the corresponding PCC rule, and receive the PCC decision provision response message sent by the source network access gateway;

the network anchor point comprises a policy and charging enhancement function entity (PCEF), receives a resource release message sent by the source network access gateway, releases related resources of a source network, receives a charging rule issued by the PCRF and charges;

the source network access gateway is connected with the network anchor point based on a mobile IP protocol, comprises a PCEF (policy and charging enforcement function) of the source network for carrying out IP-CAN (Internet protocol-controller area network) bearing control, receives a PCC (policy and charging control) decision providing message sent by the PCRF, triggers the PCEF to release corresponding bearing and related resources in the source network, sends a PCC decision providing response message to the PCRF, and sends a resource release message to the network anchor point.