WO2007112621A1

WO2007112621A1 - A method for keeping the consistency of the ip addresses de-registration of ps domain and ims domain

Info

Publication number: WO2007112621A1
Application number: PCT/CN2006/003129
Authority: WO
Inventors: Zhendong Li
Original assignee: Zte Corporation
Priority date: 2006-04-04
Filing date: 2006-11-21
Publication date: 2007-10-11
Also published as: CN101052054A; CN101052054B

Abstract

A method for keeping the consistency of the IP addresses de-registration of PS domain and IMS domain includes: in the network structure of PS domain and IMS domain of the present mobile core-network, the signaling path is setup by normal registration and de-registered when the normal de-registration occurs, then determine that the corresponding relation exists between the IP address and IMS domain, i.e. the IMS de-registration is under-done, if AGW de-registers the IP address; if so, the IMS de-registration is completed from bottom to top finally, and AGW informs the corresponding PDF/PCRF, P-CSCF, S-CSCF to implement the IMS application layer de-registration for UE; otherwise, stop the de-registration. The method ensures the consistency of the IP address de-registration of PS domain and IMS domain, and the IMS user identifier registered on the IP address can also be de-registered when the IP address of UE is de-registered in PS domain.

Description

TECHNICAL FIELD The present invention relates to the field of mobile communications technologies, and in particular, to a method for maintaining logout consistency of a PS domain and an IMS domain IP address. BACKGROUND With the development of wireless technologies, mobile communications can not only provide traditional voice services, but also provide various multimedia applications, such as video, conference, presence services, and the like. At the same time, mobile core networks are experiencing an evolution from traditional circuit-switched to all-IP (ALL IP) networks. In this context, 3GPP and 3GPP2 organization has proposed the Multimedia Subsystem (IMS, IP Multimedia Subsystem) ₀ ALL IP based network

IMS is an application layer call control system that is superimposed on the PS (Packet Switch) domain. That is, the PS domain can exist separately to provide packet services; and the IMS must be established on top of the PS domain. FIG. 1 shows a block diagram of the overall structure between the IMS domain and the PS domain network element in the mobile core network. For the sake of simplicity, many network elements not related to the present invention are omitted in FIG. 1. The dotted line in Fig. 1 indicates the signaling flow, and the solid line in Fig. 1 indicates the data flow. As shown in Figure 1, the AGW (Access Gate Way) of the PS domain in the visited network is responsible for IP address allocation/drying and bearer establishment; P-CSCF (Proxy - Call Session Control Function) Function) is the first application layer access point of the user in the IMS domain, and the proxy user performs various functions; P-CSCF, S-CSCF (Serving CSCF, Serving Call Session Control Function), HSS (Home Subscriber Server, Home Subscriber) The network element such as the server participates in the registration/deregistration of the IMS ^«. Since the IMS is superimposed on the PS domain, the normal registration and logout sequence is: PS registration -> IMS domain registration -> IMS domain logout -> PS logout. At the same time, whether it is 3GPP2 or 3GPP standards, (3GPP TS23.228 and 3GPP2 X.S0013-002), the following three IMS deregistration methods are proposed: (a) IMS logout initiated by the user equipment (User Equipment);

(b) IMS cancellation initiated by HSS;

(c) IMS revocation initiated by S-CSCF/AS (Application Server). The above three IMS deregistration methods are essentially application layer deregistration. The starting point is that the underlying bearer is normal, that is, the normal registration and logout sequence cannot be destroyed. However, when the PS domain is deregistered from the IP address of the UE for a specific reason, the PS registration -> IMS domain registration -> PS logout occurs, which destroys the prescribed normal registration and logout sequence, then the current mechanism The IMS domain control network element cannot be notified in time to inform the IMS i or the control network element that the user is or should be logged out at the IMS i. This causes, in some IMS services, the user's status is incorrect. For example, after the PS domain logs out the user IP address, the user PS domain is not online, but in the IMS domain, the user still exists. When the user's call is forwarded, when the call is forwarded to the PS domain, an error occurs and the user is found to be unreachable. For a simple IP, since the IP address is dynamically allocated, the AGW can be assigned after the user A's IP address is logged out. User B is provided, but the user A has not been logged out in the IMS or within the IMS domain and is still associated with the IP address. This leads to inconsistency in the system status and may be a security risk. All of this may not be resolved until the IMS periodic re-registration expires. After the IMS periodic re-registration expires, the user can initiate re-registration and the user is logged out. However, at this time, since the IMS re-registration expires due to the IMS re-registration expiration, the IMS re-registration cannot be performed on time, and the user cannot be logged on the IMS i. As can be seen in Figure 1, there can be a signaling path between the IMS and the PS domain, which is composed of the P-CSCF, Policy Function (PCR) (Policy Decision Function)/PCRF (Policy and Charging Rules Function) Billing rules function);), AGW components, they have interfaces from top to bottom. The policy function entity may be a PDF network element or a PCRF network element. For the sake of simplicity, it is collectively referred to as PDF/PCRF. In the visited network, there may be multiple P-CSCFs, multiple PDF/PCRFs, and multiple AGWs.

There is a many-to-many relationship between P-CSCF and PDF/PRCF, that is, one PDF/PC F can serve multiple P-CSCFs, and one P-CSCF can also interact with multiple PDF/PRCFs. PDF/PCRF and AGW can also be a many-to-many relationship. After the user UE accesses the network, only a PPP (Point-to-Point Protocol) session is established with one AGW, and only one P-CSCF is selected as its proxy. As shown in FIG. 2, the process of establishing a signaling path between a PS domain and an IMS domain in a prior art session is described. For the sake of simplicity, other network element processes have been omitted here. Step 110: The P-CSCF initiates a resource reservation, and initiates a request to a PDF/PCRF. Step 120: After receiving the request, the PDF/PCRF generates an authorization token and sends the authorization token to the P-CSCF. Step 130: The P-CSCF receives the request. After the authorization token is sent to the user UE, step 140: The user UE requests the resource from the AGW by using the received authorization token. Step 150: After receiving the request of the UE, the AGW according to the information in the authorization token (about PDF/ PCRF), initiates an authorization request to the corresponding PDF/PCRF. Through this series of signaling interactions, the signaling path between the P-CSCF, PDF/PCRF and AGW is established. However, the signaling path has the following characteristics: a) the path is established during each session; b) different sessions of the user UE, possibly different PDF/PCRF appearing in the path, but in the same session, PDF/ The PCRF is unique; c) After the session is over, the signaling path information is released. It can be seen that when the AGW releases the IP address, there is no signaling path to find the correct P-CSCF from the bottom up, and the IMS domain NE cannot be notified to perform IP address deregistration, which will result in the PS domain and the IMS domain IP address. Inconsistent situations occur. Therefore, it is necessary to utilize a structure between the existing P-CSCF, PDF/PCRF, and AGW to propose a method for maintaining the consistency of the IP address of the IMS domain and the PS domain. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a PS domain and an IMS domain IP address to be deregistered. The method of ensuring the consistency of the IP address of the PS domain and the IMS domain in the mobile core network to resolve the consistency between the IP address and the user in the IMS domain, and ensuring that the IP address of the UE is in the PS i or is logged out. At this time, the IMS user ID registered on the IP address is also logged out. In order to achieve the above object, the present invention provides a method for maintaining the logout consistency of the IP address of the PS domain and the IMS domain, so as to ensure that the user equipment is also logged out in the IMS domain after the IP address of the user equipment is logged off by the AGW in the PS domain. The method includes the following steps:

(1) Establishing a signaling path between the PS domain and the IMS domain by establishing a correspondence between the IP address of the user equipment and the P-CSCF PDF/PCRF and the AGW in the normal IMS application layer registration process;

(2) In the normal IMS application layer deregistration process, the signaling path between the PS domain and the IMS domain is cancelled by deregistering the correspondence between the IP address of the user equipment and the P-CSCF, the PDF/PCRF, and the AGW;

(3) After the AGW deregisters the IP address of the user equipment, if it finds the correspondence between the IP address of the user equipment and the PDF/PCRF, it sends an IP address revocation message to the corresponding PDF/PCRF, and deletes the ^" relationship;

(4) After the PDF/PCRF receives the IP address logout message, if the mapping between the IP address of the user equipment and the P-CSCF is found, the IP address logout message is sent to the corresponding P-CSCF, and the relationship is deleted. ;

(5) After the P-CSCF receives the IP address logout message, if the user equipment is still in the registration state, the P-CSCF sends an IP address logout message to the S-CSCF corresponding to the user equipment, and deletes the IP address between the user equipment and the PDF/PCRF. Correspondence relationship

(6) After receiving the IP address logout message, the S-CSCF initiates normal IMS application layer logout. Step (1) includes:

(1-1) The user equipment completes registration with the normal IMS application layer of the home network;

( 1-2 ) After receiving the normal registration success message returned by the home network, the P-CSCF uses The device IP address sends a registration notification message to the corresponding PDF/PCRF;

(1-3) After receiving the registration notification message, the corresponding PDF/PCRF sends a registration notification message to the AGW that manages the IP address of the user equipment;

(1-4) After receiving the registration notification message, the AGW records the correspondence between the IP address of the user equipment and the PDF/PCRF, and sends an acknowledgement message to the PDF/PCRF;

(1-5) After receiving the acknowledgement message, the PDF/PCRF records the correspondence between the IP address of the user equipment and the P-CSCF, and sends an acknowledgement message to the P-CSCF.

( 1-6 ) After receiving the acknowledgement message, the P-CSCF records the correspondence between the IP address of the user equipment and the PDF/PCRF, and forwards the normal registration success message to the user equipment. The normal registration success message in step (1-2) is a 200 OK message. The registration notification message sent in the step (1-2) adopts the Diameter protocol, and the registration notification message includes at least the user equipment IP address and the P-CSCF address or name. The registration notification message sent in the step (1-3) adopts the Diameter or Radius protocol, and the registration notification message includes at least the user equipment IP address and the PDF PCRF address or name. Step ( 2 ) includes:

(2-1) After determining that the user equipment is logged out, the P-CSCF sends a logout notification message to the corresponding PDF/PCRF according to the IP address of the user equipment, and deletes the correspondence between the IP address of the user equipment and the PDF/PCRF;

(2-2) After receiving the logout notification message, the PDF/PCRF sends a logout notification message to the AGW that manages the IP address of the user equipment, and deletes the correspondence between the IP address of the user equipment and the P-CSCF;

(2-3) After receiving the logout notification message, the AGW searches for and deletes the correspondence between the IP address of the user equipment and the PDF/PCRF. The step (2-1) further includes: if the P-CSCF does not find the correspondence between the user equipment IP address and the PDF/PCRF, the logout notification message is not sent, and the logout is stopped; the step (2-2) further includes if the PDF/ If the PCRF does not find the AGW that manages the IP address of the user equipment, the logoff notification message is not sent, and the logout is stopped. Step (2-3) further includes if the AGW does not find the correspondence between the IP address of the user equipment and the PDF/PCRF, Stop logging out. The logout notification message in step (2-1) adopts the Diameter protocol, and the logoff notification message includes at least the user equipment IP address and the P-CSCF address or name. The logout notification message sent in step (2-2) adopts the Diameter or Radius protocol, and the logout notification message includes at least the user equipment IP address and the PDF/PCRF address or name. After the AGW deregisters the IP address of the user equipment in step (3), if the mapping between the IP address of the user equipment and the PDF/PCRF is not found, the logout is stopped. The IP address logout message sent in step (3) adopts the Diameter or Radius protocol, and the IP address logout message includes at least the deregistered IP address message. After the PDF/PCRF receives the IP address logout message in step (4), if the correspondence between the IP address of the user equipment and the P-CSCF is not found, the logout is stopped. The IP address logout message sent in step (4) adopts the Diameter protocol, and the IP address logout message includes at least the deregistered IP address message. After the P-CSCF receives the IP address logout message in step (5), if the user equipment is in the logout state, the logout is stopped. With the above technical solution, the present invention can maintain the IP address consistency between the PS domain and the IMS domain when the AGW of the PS domain deregisters the IP address of the user equipment, and ensures that the IMS registered on the IP address when the IP address of the UE is logged off is ensured. The user ID can also be logged out. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, In the drawings: FIG. 1 is a network structure diagram between a user UE, a P-CSCF, a PDF/PCRF, and an AGW; FIG. 2 is a flowchart of a signaling path establishment between a UE and an IMS domain in a prior art session; 3 is a flow chart of a method for maintaining PS-domain and IMS domain IP address deregistration consistency according to the present invention; FIG. 4a and FIG. 4b are data tables of P-CSCF and PDF/PCRF network element pre-configuration according to an embodiment of the present invention. FIG. 5a, FIG. 5b, and FIG. 5c are schematic diagrams of information tables dynamically stored in a P-CSCF, a PDF/PCRF, and an AGW according to an embodiment of the present invention; FIG. 6 is an IMS registration of an unregistered user according to an embodiment of the present invention; FIG. 7 is a flowchart of an IMS application layer deregistration of a user UE according to an embodiment of the present invention; and FIG. 8 is a flowchart of an AGW deregistering an IP address of a user UE according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the accompanying drawings. Referring to FIG. 3, a method for maintaining logout consistency of a PS domain and an IMS domain IP address according to the present invention includes:

(1) In the normal IMS application layer registration process, by establishing the user equipment IP address and Corresponding relationship between P-CSCF, PDF/PCRF, and AGW, establishing a signaling path between the PS domain and the IMS domain;

(3) After the AGW deregisters the IP address of the user equipment, if the mapping between the IP address of the user equipment and the PDF/PCRF is found, the AGW sends an IP address revocation message to the corresponding PDF/PCRP, and deletes the ^" relationship;

(4) After receiving the IP address logout message, the PDF/PCRF sends an IP address logout message to the corresponding P-CSCF and deletes the corresponding relationship if the mapping between the IP address of the user equipment and the P-CSCF is found.

(6) After receiving the IP address logout message, the S-CSCF initiates normal IMS application layer logout. Further, the step (1) includes:

(1-2) After receiving the normal registration success message returned by the home network, the P-CSCF sends a registration notification message to the corresponding PDF/PCRF according to the user equipment IP address;

( 1-5 ) After receiving the confirmation message, PDF/PCRF records the user equipment IP address and P-CSCF. Correspondence between the two, and send a confirmation message to the P-CSCF;

( 1-6 ) After receiving the acknowledgement message, the P-CSCF records the correspondence between the IP address of the user equipment and the PDF/PCRF, and forwards the normal registration success message to the user equipment. Optionally, the normal registration success message in step (1-2) is a 200 OK message. Optionally, the registration notification message sent in the step (1-2) adopts a Diameter protocol, and the registration notification message includes at least a user equipment IP address and a P-CSCF address or a name. Optionally, the registration notification message sent in the step (1-3) adopts a Diameter or Radius protocol, and the registration notification message includes at least a user equipment IP address and a PDF/PCRF address or a name. Further, step (2) includes:

(2-3) After receiving the logout notification message, the AGW searches for and deletes the correspondence between the IP address of the user equipment and the PDF/PCRF. Step (2-1) further includes: if the P-CSCF does not find the correspondence between the user equipment IP address and the PDF/PCRF, the logout notification message is not sent, and the logout is stopped; the step (2-2) further includes if the PDF/ If the PCRF does not find the AGW that manages the IP address of the user equipment, the logoff notification message is not sent, and the logout is stopped. Step (2-3) further includes: if the AGW does not find the correspondence between the IP address of the user equipment and the PDF/PCRF, Stop logging out. Optionally, the logout notification message in step (2-1) adopts a Diameter protocol, and the logoff notification message includes at least a user equipment IP address and a P-CSCF address or a name. Optionally, the logout notification message sent in step (2-2) adopts a Diameter or Radius protocol, and the logoff notification message includes at least a user equipment IP address and a PDF/PCRF address or a name. Further, after the AGW deregisters the IP address of the user equipment in step (3), if the correspondence between the IP address of the user equipment and the PDF/PCRF is not found, the logout is stopped. Optionally, the IP address deregistration message sent in step (3) adopts the Diameter or Radius protocol, and the IP address deregistration message includes at least the deregistered IP address message. Further, after receiving the IP address deregistration message, the PDF/PCRF in step (4) stops the logout if the correspondence between the IP address of the user equipment and the P-CSCF is not found. Optionally, the IP address deregistration message sent in step (4) adopts the Diameter protocol, and the IP address deregistration message includes at least the deregistered IP address message. Further, after the P-CSCF receives the IP address logout message in step (5), if the user equipment is in the logout state, the logout is stopped. The purpose of the invention is to ensure consistency between the IP address and the user in the IMS core network. The invention is described in detail below with reference to the accompanying drawings, but not by way of limitation. FIG. 1 is a network structure diagram of a user UE, a P-CSCF, and a PDF/PCRF AGW. The embodiment of the present invention is implemented based on the network structure shown in FIG. 1. Figures 4a, 4b, 5a, 5b, and 5c show the information structure that needs to be saved on the P-CSCF, PDF/PCRF, and AGW in order to implement the functions of the present invention, that is, the relationship between each network element and the user's IP address. Figure 4a shows a pre-configured data table on the P-CSCF that indicates which PDF/PCRFs are available for an address range. The address range characterizes the AGW set (one or more;), and this structure represents a AGW set, which PDF/PCRF interfaces. Figure 4b shows a pre-configured data table on PDF/PCRF, which indicates which address range is associated with which AGW. The address range represents an AGW, and this structure represents The relationship between the AGW and the address range. The contents of Figures 4a, 4b are pre-configured, which describes the connection relationship from the P-CSCF to the PDF/PCRF, to the AGW, in various configurations. Figure 5a shows a data table on the P-CSCF that represents the association between an IP address and a PDF/PCRF. Figure 5b shows a data table on PDF/PCRF that represents the association between an IP address and a P-CSCF. Figure 5c shows a data table on the AGW that represents the association between an IP address and a PDF/PCRF. As shown in FIG. 6, a flow when a user performs normal IMS registration according to the present invention is described. The registration here refers specifically to the registration process of an unregistered user, not the re-registration process. When the IMS registration is initiated by the unregistered user, the P-CSCF initiates a signaling path between the P-CSCF, the PDF/PCRF, and the AGW to maintain the consistency of the IP addresses of the PS domain and the IMS domain. The specific process is as follows: Step 210: The normal IMS application layer registration initiated by the UE, for simplicity, the specific implementation of this step is not described again; Step 220: The P-CSCF receives a 200 OK message for the registration process; Step 230: P The CSCF selects an appropriate PDF/PCRF from the data table shown in FIG. 4a according to the IP address of the user UE, and sends a registration notification message to the PDF/PCRF, where the message includes at least the UE IP address and the P-CSCF address or name. The message may be, but is not limited to, the Diameter protocol; Step 240: After receiving the registration notification message, the PDF/PCRF locates the data table shown in FIG. 4b, finds the AGW that manages the IP address, and sends a registration notification message to the AGW, at least the message Contains the UE IP address and the PDF/PCRF address or name, which may be, but is not limited to, the Diameter or Radius protocol; Step 250: After receiving the registration notification message, the AGW adds a record (UE IP address, PDF/PCRF address or name) in the data table shown in FIG. 5c, and the AGW sends a confirmation message to the PDF/PCRF; Step 260: PDF After receiving the notification confirmation message, the PCRF adds a record (UE IP address, P-CSCF address or name) in the data table shown in FIG. 5b, and the PDF/PCRF sends an acknowledgement message to the P-CSCF; Step 270: After receiving the notification confirmation message, the P-CSCF adds a record (UE IP address, PDF/PCRF address or name) to the data table shown in FIG. 5a, and the P-CSCF forwards the 200 OK message to the UE. The AGW may be a PDSN (Packet Data Serving Node) network element. As shown in Fig. 7, the flow of the normal IMS logout according to the present invention is described. When the user IMS logs out, it is initiated by the P-CSCF to release the signaling path between the P-CSCF, the PDF/PCRF, and the AGW. For the sake of simplicity, only the flow specific to the present invention is shown in the figure, and the rest of the flow is consistent with the normal logout. The specific process is as follows: Step 310: After confirming that the user UE is logged out, the P-CSCF searches for the appropriate record from the data table shown in FIG. 5a, and if not, does not perform further operations on the PDF/PCRF, if it is found to go to step 320; Step 320 The P-CSCF sends a logout notification message to the PDF/PCRF according to the found record (UE IP address, PDF/PCRF address or name), and the message includes at least the UE IP address and the P-CSCF address or name, and the message may be Using, but not limited to, the Diameter protocol, the corresponding record in the table shown in FIG. 5a is deleted; Step 330: After receiving the logout notification message, the PDF/PCRF searches for the AGW that manages the IP address of the UE from the data table shown in FIG. 4b. Sending a logout notification message to the AGW, where the message may be, but not limited to, the Diameter or Radius protocol, and delete the user IP address and the record corresponding to the P-CSCF stored in FIG. 5b; Step 340: After receiving the logout notification message, the AGW searches for and deletes the record corresponding to the IP address and the PDF/PCRF in FIG. 5c. As shown in FIG. 8, the flow of IMS logout may occur when the AGW deregisters the IP address of the user UE according to the present invention. When the AGW cancels the user IP address, the specific steps for initiating the IMS user to log out are as follows: Step 410: The AGW cancels the IP address of a user UE. Step 420: The AGW searches for the record corresponding to the IP address in the data table shown in Figure 5c. If not, no subsequent operation is required. If found, the IP address is sent to the corresponding PDF/PCRF in the record. The message, the IP address logout message may be, but is not limited to, the Diameter or Radius protocol, and the corresponding record in the table of Figure 5c is deleted. Step 430: After receiving the IP address logout message, the PDF/PCRF searches for the record corresponding to the IP address in the data table shown in FIG. 5b. If not, no subsequent operations are required. If found, an IP address deregistration message is sent to the corresponding P-CSCF in the record. The IP address deregistration message may be, but not limited to, the Diameter protocol. At the same time, delete the corresponding record in the table of Figure 5b. Step 440: After receiving the IP address logout message, the P-CSCF searches for the user identifier using the P-CSCF as a proxy, and sends a user IP address logout message to the S-CSCF registered by the users. At the same time, the corresponding record in the table shown in Fig. 5a is deleted. Step 450: After receiving the IP address deregistration message sent by the P-CSCF, the S-CSCF initiates a normal user IMS application layer to log out. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A method for maintaining the write-off consistency of the IP address of the PS domain and the IMS domain, to ensure that the user equipment is also logged out in the IMS domain after the user equipment IP address is logged off by the AGW in the PS domain, and is characterized in that Including the following steps:

(1) In the normal IMS application layer registration process, the PS domain and the IMS domain are established by establishing a correspondence between the user equipment IP address and the P-CSCF, the PDF/PCRF., and the AGW. Signaling path between

(2) in the normal IMS application layer deregistration process, the PS domain and the domain are deregistered by deregistering the correspondence between the user equipment IP address and the P-CSCF, the PDF/PCRF, and the AGW. Said signaling path between IMS domains;

(3) After the AGW deregisters the IP address of the user equipment, if the mapping between the IP address of the user equipment and the PDF/PCRF is found, the AGW sends an IP address logout message to the corresponding PDF/PCRF. And deleting the corresponding relationship;

(4) After receiving the IP address deregistration message, the PDF/PCRF sends an IP address to the corresponding P-CSCF to log out if the correspondence between the IP address of the user equipment and the P-CSCF is found. a message, and deleting the corresponding relationship;

(5) After receiving the IP address deregistration message, the P-CSCF sends an IP address deregistration message to the S-CSCF corresponding to the user equipment, and deletes the user, if the user equipment is still in the registration state. Correspondence between the device IP address and the PDF/PCRF;

(6) After receiving the IP address deregistration message, the S-CSCF initiates a normal IMS application layer to log out.

2. The method according to claim 1, wherein the step (1) comprises:

(1-1) the user equipment completes registration with a normal IMS application layer of the home network;

(1-3) after the corresponding PDF/PCRF receives the registration notification message, The AGW that manages the IP address of the user equipment sends a registration notification message;

(1-4) after receiving the registration notification message, the AGW records a correspondence between the IP address of the user equipment and the PDF/PCRF, and sends an acknowledgement message to the PDF/PCRF;

(1-5) after receiving the acknowledgement message, the PDF/PCRF records a correspondence between the user equipment IP address and the P-CSCF, and sends a confirmation message to the P-CSCF;

(1-6) after receiving the acknowledgement message, the P-CSCF records a correspondence between the IP address of the user equipment and the PDF/PCRF, and forwards the normal registration success message to the user equipment. .

The method according to claim 2, wherein the normal registration success message described in the step (1-2) is a 200 OK message.

The method according to claim 2, wherein the registration notification message sent in the step (1-2) adopts a Diameter protocol, and the registration notification message includes at least the user equipment IP address and the The P-CSCF address or name.

The method according to claim 2, wherein the registration notification message sent in the step (1-3) adopts a Diameter or Radius protocol, and the registration notification message includes at least the user equipment IP address. And the PDF/PCRF address or name.

The method according to claim 1, wherein the step (2) comprises:

(2-1) the P-CSCF determines that the user equipment is logged out, sends a logout notification message to the corresponding PDF/PCRF, and deletes the user equipment IP address and the PDF/ Correspondence between PCRFs;

(2-2) after receiving the logout notification message, the PDF/PCRF sends a logout notification message to the AGW that manages the IP address of the user equipment, and deletes the user equipment IP address and the P-CSCF. Correspondence between them;

(2-3) After receiving the logout notification message, the AGW searches for and deletes the correspondence between the IP address of the user equipment and the PDF/PCRF.

7. The method of claim 6 wherein:

The step (2-1) further includes: if the P-CSCF does not find the correspondence between the user equipment IP address and the PDF/PCRF, the logoff notification message is not sent, and the logout is stopped;

The step (2-2) further includes: if the PDF/PCRF does not find the AGW that manages the IP address of the user equipment, the logoff notification message is not sent, and the logout is stopped;

The step (2-3) further includes stopping the logout if the AGW does not find the correspondence between the user device IP address and the PDF/PCRF.

The method according to claim 6, wherein the logout notification message in the step (2-1) adopts a Diameter protocol, and the logout notification message includes at least the user equipment IP address and P- CSCF address or name.

The method according to claim 6, wherein the logout notification message sent in the step (2-2) adopts a Diameter or Radius protocol, and the logout notification message includes at least a user equipment IP address and a PDF. /PCRF address or name.

The method according to claim 1, wherein, after the AGW cancels the IP address of the user equipment in the step (3), if the user equipment IP address is not found, the PDF/PCRF is not found. If there is a correspondence between them, the logout is stopped.

The method according to claim 1, wherein the IP address deregistration message sent in the step (3) adopts a Diameter or Radius protocol, and the IP address deregistration message includes at least a deregistered IP address message. .

The method according to claim 1, wherein in the step (4), after the PDF/PCRF receives the IP address deregistration message, if the user equipment IP address is not found, The correspondence between the P-CSCFs stops logging out.

The method according to claim 1, wherein the IP address deregistration message sent in the step (4) adopts a Diameter protocol, and the IP address deregistration message includes at least a deregistered IP address message.

The method according to claim 1, wherein, after the P-CSCF in the step (5) receives the IP address logout message, if the user equipment is in the logout state, the logoff is stopped. .