WO2011097986A1

WO2011097986A1 - Method and system for sending pcc policy information

Info

Publication number: WO2011097986A1
Application number: PCT/CN2011/070573
Authority: WO
Inventors: 蒋陶; 孙默; 周晓云; 周星月
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-02-11
Filing date: 2011-01-25
Publication date: 2011-08-18
Also published as: CN102158562A

Abstract

A method and system for sending Policy and Charging Control (PCC) policy information are provided by the invention. When the service information, which is provided to a Policy and Charging Rules Function (PCRF) by an Application Function (AF) and used to constitute PCC rules, is based on the transformed IP address and port number in an external packet network, i.e. when a network address translation function entity is deployed, the PCRF in the invention obtains the untranslated address information of the service policy information according to an Network Address Translation (NAT) correspondence table generated by the network address translation function entity, performs PCC policy association and policy decision for services according to the untranslated address information of the service policy information, and performs the PCC policy rules providing flow to send PCC rules to a Policy and Charging Enforcement Function (PCEF). It is ensured that the PCRF associates the service policy information accurately and send the PCC policy information to the corresponding PCEF correctly.

Description

Method and system for issuing PCC strategy information

The present invention relates to the Evolved Packet System (EPS) technology of the 3rd Generation Partnership Project (3GPP), and particularly relates to a policy and charging control (PCC) in a network address translation scenario. , Policy and Charging Control) Method and system for policy information. Background technique

Figure 1 is a schematic diagram of the composition of an existing Evolved Packet System (EPS) of the 3rd Generation Partnership Project (3GPP), as shown in Figure 1, which mainly includes the evolved universal mobile communication system land. E-UTRAN (Evolved Universal Terrestrial Radio Access Network), Mobility Management Entity (MME), Serving Gateway (S-GW, Serving Gateway), Packet Data Network Gateway (P-GW, Packet Data) Network Gateway (also known as PDN GW), Home Subscriber Server (HSS), Policy and Charging Rules Function (PCRF) entity and other supporting nodes. The E-UTRAN is connected to the MME through the S1-MME, and the MME is connected to the HSS through the S6a. The S-GW is an access gateway device connected to the E-UTRAN, and forwards data between the E-UTRAN and the P-GW, and is responsible for The paging waiting data is buffered, and the S-GW is connected to the EUTRAN through the SI-U, connected to the MME through the S11, connected to the PCRF through the Gxc, and connected to the P-GW through the S5; the P-GW is the EPS and the packet data network ( The border gateway of the PDN (Packet Data Network) is responsible for accessing the PDN and forwarding data between the EPS and the PDN. The P-GW is connected to the PCRF through the Gx, and is connected to the IP service provided by the operator through the SGi. The PCRF is connected to the IP service through the Rx interface. Carrier Internet Protocol (IP, Internet Protocol) The service network interface is connected to obtain the service information, and is connected to the gateway device in the 3GPP network through the Gx/Gxa/Gxb/Gxc interface, and is responsible for initiating the establishment of the IP bearer, ensuring the quality of service (QoS, Quality of Service) of the service data, and Perform billing control.

2 is a schematic diagram of a PCC structure of an existing EPC dynamic policy charging control. As shown in FIG. 2, a Policy and charging enforcement function (PCEF) resides in a P-GW of an EPS system. The PCRF exchanges information with the PCEF through the Gx interface. when

When the interface between the P-GW and the S-GW is based on PMIPv6, the S-GW also has policy control functions, called bearer binding and event reporting (BBERF, Bearer Binding and Event Reporting).

Function ), BBERF and PCRF exchange information through the Gxc interface. At the same time, an application function (AF, Application Function) for providing a service to the user equipment (UE) is provided through the Rx interface.

The PCRF sends service information for formulating Policy and Charging Control (PCC) or QoS policies.

The EPS can provide billing system charging information for the billing system, including offline billing and online billing. For online charging, when the UE accesses through 3GPP, the P-GW interacts with the OCS to perform credit control. The P-GW generates the charging information and sends the charging information to the charging system, where the charging identifier is included, and the charging identifier is referred to as an Access-Network-Charging-Identifier, which may also be referred to as a bearer layer meter. Fee identification.

At the same time, the application server can also provide the accounting information of the application layer to the charging system, and the charging information is also identified by the charging identifier. The charging identifier is called an application function charging identifier (AF-Charging-Identifier). In the prior art, the charging identifier is generated by the AF and sent to the relevant application server.

In order to enable the charging system to associate the bearer layer charging information generated by the user to access a certain service with the application layer charging information, the P-GW/PCEF and the AF must send the respective generated charging identifiers to the other party through the PCRF. In this way, when the P-GW/PCEF sends the bearer layer charging information of the access network charging identifier to the charging system, the AF-Charging-Identifier is carried, and when the application server sends the applicable application function charging to the charging system. Carrying the identified billing information The Access-Network-Charging-Identifier's billing system can associate the bearer layer with the application layer billing information.

The IPv6 transition method was first studied in 1994 from the IETF NGTRAN working group. In 1996, 6Bone was established for experimentation. In 1998, the first group of IPv6 standard RFCs was released. In 2003, the NGTRAN working group was closed. At that time, the mainstream technologies that were expected to have been completed were completed. After that, the IETF did not generate RFCs for IPv6 in large quantities. China's CNGI experimental network also reached its first high point in 2003/2004. At that time, the main IPv6 transition technologies used in CNGI network deployment were the main IPv6 related issues at that time. The RFC, the transition technology at that time, mainly focused on: dual stack, translation and tunneling technologies. Until 2007, with DS-Lite (D-Stack Lite), Carrier Grade Network Address Translation (CGN), address port (A+P, Address + Port), IPv6 to IPv4 network address translation technology (NAT64, Network Address Translation 6 to 4), host translation-based Prefix-NAT and other new transition technologies, the IETF re-agreed in 2008 to develop new translation and tunneling technologies .

The current popular IPv6 migration technologies are mainly PNAT technology, GI-DS-LITE technology and NAT64+DNS64 technology. Among them, the PNAT technology and the NAT64+DNS64 technology need to deploy an IPv6 address to an IPv4 address address translator between the EPC core network and the external packet data network, and the GI-DS-LITE technology needs to deploy the bearer at the edge of the EPC core network. The Level Network Translation Gateway (CGN) translates between the IPV4 private network address and the IPV4 public network address. Therefore, no matter which IPv6 migration technology needs to change the IP address. The existence of the IP address translation device causes the same PDN connection to carry the IP address and port number used inside the EPC, which is different from the IP address and port number used in the external packet network, if the AF is provided to the PCRF for formulating the PCC. The service information of the rule is based on the transformed IP address and port number in the external packet network, and the PCRF needs to formulate and deliver the PCC rule based on the untransformed IP address and port number to the execution unit PCEF of the PCC rule. The PCRF cannot obtain the corresponding information of the IP address translation. Therefore, the PCRF cannot provide the service policy information provided by the AF. The PDN connection dedicated bearer is associated to specify and deliver the PCC rule corresponding to the dedicated bearer to the PCEF. Summary of the invention

In view of the above, the main purpose of the present invention is to provide a method and a system for transmitting PCC policy information, which can ensure that the PCRF correctly sends the PCC policy information to the corresponding PCEF.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A method for delivering PCC policy information, including:

The policy and charging rule function unit PCRF determines that the address information related to the received service policy information is translated, and obtains the address of the service policy information that has not been translated by the address according to the network address translation NAT correspondence table generated by the network address translation function entity. Information

The PCRF performs the association and policy decision of the service policy and the charging control PCC policy according to the address information of the service policy information that has not been translated by the address, and executes the PCC policy rule providing process to deliver the PCC rule to the policy and charging execution function PCEF.

The PCRF determines that the address information related to the service policy information is untranslated, and the method further includes:

The PCRF performs the association and policy decision of the service PCC policy according to the address information, and then executes the PCC policy rule providing process to deliver the PCC rule to the PCEF.

a network address translation adapter and a functional entity are disposed in the PCRF;

The obtaining the address information of the service policy information that has not been translated by the address includes:

The functional entity on the PCRF sends a network address translation information query message carrying the service flow address information that needs to be reverse translated to the network address translation adapter;

The network address translation adapter obtains a NAT correspondence table including the service policy address information from the network address translation function entity, and reverse-translates the service flow address information;

The network address translation adapter sends a network address translation information query response message carrying the reverse translated service flow information to the functional entity in the PCRF. The network address translation function entity includes: translation of an IPv6 address to an IPv4 address, and/or translation of an IPV4 address to an IPv4 address, and/or translation of an IPv4 address to an IPv6 address.

The method of determining includes:

According to the application function AF, the purpose of the service flow information is to be determined by the PCRF configuration attribute. If the PCRF is deployed in the NAT-converted network, it is determined that the address information related to the received service policy information is translated.

A system for delivering PCC policy information includes at least a policy and charging rule function unit PCRF, a network address translation function entity, a policy, and a charging execution function PCEF, where

The PCRF is configured to determine that the address information related to the received service policy information is translated, and obtain the address information of the service policy information that has not been translated by the address according to the network address translation NAT correspondence table generated by the network address translation function entity; The address information of the service policy information translated by the address, the association between the business policy and the charging control PCC policy, and the policy decision, and the PCC policy rule providing process is sent to the PCEF for the policy and charging execution function PCEF;

a network address translation function entity, configured to convert an IP address and generate a NAT correspondence table;

The PCEF, which resides in the P-GW, receives the PCC rules sent from the PCRF.

The system also includes an AF for sending to the PCRF via the Rx interface for developing a PCC or

Business policy information of the QoS policy.

The PC-resident P-GW is further configured to receive PCC rules from the PCRF, install and execute PCC rules, and initiate an IP-CAN bearer setup, modification, or deletion process as needed.

The PCRF is provided with at least a network address translation adapter and a functional unit for processing PCC policy information;

The functional unit on the PCRF is configured to receive the service policy information from the AF through the Rx interface, and determine that the address information related to the service policy information is translated, and send an indication notification to the network address translation adapter. Address information from the network address translation adapter, perform association and policy decisions for the service PCC policy, and perform PCC policy rule provisioning The process sends a PCC rule to the PCEF.

The network address translation adapter is configured to receive the indication notification, interact with the network address translation function entity, obtain a NAT correspondence table including the service policy address information, and perform reverse translation on the received address information of the service policy information, and obtain the The address information of the service policy information translated by the address is returned to the functional entity on the PCRF.

The network address translation function entity is deployed in combination with the P-GW, or is deployed as a separate network function unit;

The network address translation function entity is separately deployed, and the network address translation adapter and the network address translation function entity are connected by using a newly added Gxn interface; or

The network address translation function entity is deployed in combination with the P-GW, and the network address translation adapter is connected to the network address translation function entity through an existing Gx interface with the PCEF.

The network address translation function entity includes: translation of an IPv6 address to an IPv4 address, translation of an IPV4 address to an IPv4 address, and translation of an IPv4 address to an IPv6 address.

It can be seen from the technical solution provided by the present invention that the service information provided by the AF to the PCRF for formulating the PCC rule is based on the transformed IP address and port number in the external packet network, that is, the network address translation function entity is deployed. The PCRF of the present invention obtains the address information of the service policy information that has not been translated by the address according to the NAT correspondence table generated by the network address translation function entity, and performs the association of the service PCC policy according to the address information of the service policy information that has not been translated by the address. And the policy decision, and the implementation of the PCC policy rule providing process to the PCEF to issue PCC rules. The PCRF is correctly associated with the service policy information, and the PCC policy information is correctly sent to the corresponding PCEF. DRAWINGS

FIG. 1 is a schematic diagram of a composition structure of an existing 3GPP EPS;

2 is a schematic structural diagram of a PCC that supports existing EPC dynamic policy charging control; 3 is a schematic structural diagram of a system for transmitting PCC policy information in the scenario in which a network address translation function entity is deployed separately;

Figure 4 is a schematic diagram showing the structure of a system for transmitting PCC policy information in the scenario in which the network address translation function entity and the P-GW are deployed together;

5 is a flowchart of a method for transmitting PCC policy information according to the present invention;

FIG. 6 is a schematic flowchart diagram of an embodiment of sending PCC policy information according to the present invention. detailed description

3 is a schematic diagram of the structure of a system for transmitting PCC policy information in the scenario in which the network address translation function entity is deployed separately, and FIG. 4 is a scenario in which the network address translation function entity and the P-GW are deployed in a unified manner. Schematic diagram of the structure of a system that sends PCC policy information. As shown in FIG. 3 and FIG. 4, the method mainly includes an AF, a P-GW, a PCRF, and a network address translation function entity, where

The AF is used to send service policy information for formulating a PCC or QoS policy to the PCRF through the Rx interface.

P-GW, where PCEF resides, and information is exchanged between PCEF and PCRF through the Gx interface. Receive PCC rules from PCRF, install and execute PCC rules, and initiate the process of establishing, modifying, or deleting IP-CAN bearers as needed.

The network address translation function entity is used to convert an IP address and generate a NAT correspondence table. The network address translation function entity can be deployed in combination with the P-GW, that is, the network address translation function entity is set in the P-GW (as shown in FIG. 4), or can be deployed as a separate network function unit (as shown in FIG. 3). . Network address translation function entities include, but are not limited to, translation of IPv6 addresses to IPv4 addresses, translation of IPV4 addresses to IPv4 addresses, and translation of IPv4 addresses to IPv6 addresses.

A PCRF in which at least a network address translation adapter and a functional unit for processing PCC policy information are provided. Wherein, if the network address translation function entity is separately deployed, the network address translation adapter and the network address translation function entity are connected by a new Gxn interface; If the network address translation function entity is deployed in combination with the P-GW, the network address translation adapter can be connected to the network address translation function entity through the existing Gx interface with the PCEF.

a functional unit on the PCRF, configured to receive the service policy information from the AF through the Rx interface, and determine that the address information related to the service policy information is translated, and send an indication notification to the network address translation adapter; The address information of the adapter is used to perform the association and policy decision of the service PCC policy, and then the PCC policy rule providing process is executed to deliver the PCC rule to the PCEF;

a network address translation adapter, configured to receive the indication notification, interact with the network address translation function entity by using a Gxn interface or a Gx interface between the network address translation function entity, and obtain a NAT correspondence table including the service policy address information, and receive the The address information of the obtained business policy information is reverse translated, and the address information of the business policy information that has not been translated by the address is obtained and returned to the functional entity on the PCRF.

FIG. 5 is a flowchart of a method for sending PCC policy information according to the present invention. As shown in FIG. 5, the method mainly includes:

Step 500: The PCRF determines that the address information related to the received service policy information is translated, and obtains the address information of the service policy information that has not been translated by the address according to the NAT correspondence table generated by the network address translation function entity.

Step 501: Perform the association and policy decision of the service PCC policy according to the address information of the service policy information that has not been translated by the address, and execute the PCC policy rule providing process to deliver the PCC rule to the PCEF.

It can be seen from the method of the present invention that the service information provided by the AF to the PCRF for formulating the PCC rule is based on the transformed IP address and port number in the external packet network, that is, when the network address translation function entity is deployed, the present invention The PCRF obtains the address information of the service policy information that has not been translated by the address according to the NAT correspondence table generated by the network address translation function entity, and performs the association and policy decision of the service PCC policy according to the address information of the service policy information that has not been translated by the address. The PCC policy rule providing process is executed to deliver PCC rules to the PCEF. promise The PCRF correctly associates the service policy information and correctly sends the PCC policy information to the corresponding PCEF. FIG. 6 is a schematic flowchart of an embodiment of sending PCC policy information according to the present invention. In this embodiment, a UE performs network service application interaction, and AF provides service information, and the PCRF uses the network address translation adaptation proposed by FIG. 3 and FIG. 4 of the present invention. The process of implementing the IP data flow included in the service information is correctly associated with the associated bearer layer charging identifier and QoS information. It is assumed that the network address translation function entity is an independent entity in this embodiment, as shown in FIG. step:

Step 600: The user performs service access, and performs application layer interaction between the UE and the AF. In this process, the network address translation function entity generates an address translation correspondence table of the session corresponding to the related service.

Step 601: The AF sends the PCC policy information of the service to the policy formulation and decision unit in the PCRF through the Rx interface, including the address information describing the service flow, such as a quintuple, including the source IP address, the destination IP address, and the source port number. , destination port number and protocol number.

Step 602: The policy formulation and decision unit on the PCRF determines whether the network address information in the received service PCC policy information is translated by the address of the network address translation function entity. If it is determined that the network address information is not translated by NAT, step 6031 and step 6041 are performed; otherwise, execution starts from step 6032.

In this step, the basis of the judgment may be configured according to the network, for example, according to the purpose of the AF push service flow information, the PCRF configuration attribute, if the PCRF is deployed in the NAT translation network, the service flow needs to be reverse translated. The invention is not limited in its specific implementation, nor is it intended to limit the scope of the invention.

Step 6031: The PCRF performs the association and policy decision of the service PCC policy according to the address information, and then executes the PCC policy rule providing process to deliver the PCC rule to the PCEF.

Step 6041: The PCEF installs and executes the PCC rule, and initiates the process of establishing, modifying, or deleting the IP-CAN bearer as needed. End this process.

The specific implementation of step 6031 and step 5041 belongs to the prior art and is not related to the purpose of the present invention and will not be described in detail herein. Step 6032: The policy formulation and decision unit on the PCRF sends a network address translation information query message to the network address translation adapter, where the network address translation information query message carries the service flow address information that needs to be reverse translated.

Step 6042: The network address translation adapter interacts with the network address translation function entity by adding a Gxn interface, and obtains a NAT correspondence table including the service policy address information, and reverse-translates the service flow address information.

In this step, the reverse translation process includes, but is not limited to, reverse translation of the session quintuple (source IP address, destination IP address, source port number, destination port number, protocol number) of the service flow. Table 1 is a correspondence table of original session information and NAT-processed session information.

Taking Table 1 as an example, the network address translation adapter can extract the information shown in Table 1 from the NAT information, match the service flow information from the AF, and translate the service flow information before the NAT processing. Specifically, the service flow address information is converted from IPv4 session information to IPv6 session information.

Step 6052: The network address translation adapter sends a network address translation information query response message to the policy formulation and decision unit in the PCRF, where the network address translation information query response message carries the reverse translated service flow information (eg, before NAT translation). The quintuple).

Step 6062: The PCRF performs the association and policy decision of the service PCC policy according to the reverse translated service flow address information, and then executes the PCC policy rule providing process to deliver the PCC rule to the PCEF.

Step 6072: The PCEF installs and executes the PCC rule, and initiates an IP-CAN bearer setup, modification, or deletion process as needed. The specific implementation of step 5062 and step 5072 belongs to the prior art and is not related to the purpose of the present invention and will not be described in detail herein.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included. Within the scope of protection of the present invention.

Claims

Claim

A method for delivering PCC policy information, comprising:

The method according to claim 1, wherein the PCRF determines that the address information related to the service policy information is untranslated, and the method further includes:

The method according to claim 1 or 2, wherein the PCRF is provided with a network address translation adapter and a functional entity;

The network address translation adapter sends a network address translation information query response message carrying the reverse translated service flow information to the functional entity in the PCRF.

4. The method according to claim 3, wherein the network address translation function entity comprises: translation of an IPv6 address to an IPv4 address, and/or translation of an IPV4 address to an IPv4 address, and/or an ιρ _ν 4 address Translation to an IPv6 address.

The method according to claim 3, wherein the determining comprises: And determining, according to the destination PCRF configuration attribute of the application function AF to push the service flow information, if the PCRF is deployed in the NAT-transformed network, determining that the address information related to the received service policy information is translated.

A system for delivering PCC policy information, comprising: at least a policy and charging rule function unit PCRF, a network address translation function entity, a policy and a charging execution function PCEF; wherein

The network address translation function entity is configured to convert the IP address and generate a NAT correspondence table. The PCEF resides in the P-GW and receives the PCC rule delivered by the PCRF.

7. The system according to claim 6, wherein the system further comprises an AF for transmitting service policy information for formulating a PCC or QoS policy to the PCRF through the Rx interface.

The system according to claim 7, wherein the PC-resident P-GW is further configured to receive PCC rules from the PCRF, install and execute PCC rules, and initiate IP-CAN bearer establishment as needed. , modify or delete the process.

The system according to claim 7, wherein the PCRF is provided with at least a network address translation adapter and a functional unit for processing PCC policy information;

The function unit is configured to receive the service policy information from the AF through the Rx interface, and determine that the address information related to the service policy information is translated, and send an indication notification to the network address translation adapter; Translating the address information of the adapter, performing the association and policy decision of the service PCC policy, and executing the PCC policy rule providing process to deliver the PCC rule to the PCEF; The network address translation adapter is configured to receive the indication notification, interact with the network address translation function entity, obtain a NAT correspondence table including the service policy address information, and perform reverse translation on the received address information of the service policy information, and obtain the The address information of the service policy information translated by the address is returned to the functional entity on the PCRF.

The system according to claim 9, wherein the network address translation function entity is deployed in combination with the P-GW, or is separately deployed as an independent network function unit;

The system according to any one of claims 6 to 10, wherein the network address translation function entity comprises: translation of an IPv6 address to an IPv4 address, translation of an IPV4 address to an IPv4 address, and an IPv4 address to an IPv6 address. Translation.