CN104883675A - IP address distribution method, device and system - Google Patents

Abstract

The invention relates to the communication technical field, and especially relates to an IP address distribution method, device and system; the method comprises the following steps: a PGW receives a register request from a first UE, distributes an IP address for the first UE, and stores a corresponding relation between the IP address and a register expire time when receiving the first UE register expire time sent by a P-CSCF device; the PGW releases the IP address when the first UE deactivates, and does not distribute the IP address to other UEs before the register expire time arrives. The method ensures one IP address to be distributed to one UE before the register expire time arrives, so the PGW cannot send a message, sent to the UE, to other UEs after the IP address of the UE is released.

Description

A method, device and system for allocating IP addresses

technical field

The present invention relates to the field of communication technology, in particular to a method, device and system for allocating IP (Internet Protocol, Internet Protocol) addresses.

Background technique

In a VoLTE (voice over long term evolution, voice based on long-term evolution) network, a PGW (packet data network gateway, packet data network gateway) can communicate with multiple P-CSCF (proxy-call session control function, proxy-call session control function) devices to communicate. When a user equipment (User Equipment, UE) (assumed to be UE A) initiates a registration request, the PGW that receives the registration request allocates an IP address for UE A (assumed to be IP A), and will send the IP address to the UE a. UE A uses the IP address to construct a registration request sent to the P-CSCF device (assumed to be P-CSCF device A), so as to register UE A on the P-CSCF device A.

When UE A is deactivated, the PGW releases the IP address (IP A) allocated for UE A. Later, when another UE (assumed to be UE B) initiates a registration request, the PGW reassigns IP A to UE B, and UE B uses IP A to construct and send it to another P-CSCF device (assumed to be P-CSCF device B ) registration request to register UE B on P-CSCF device B.

Through the analysis of the prior art, the inventor believes that the prior art has at least the following problems:

After the PGW releases the IP address (IP A) allocated for UE A, when the registration of UE A in the IP multimedia subsystem (IP multimedia subsystem, IMS) has not expired, the session of UE A in IMS has not been released . At this time, when P-CSCF equipment A receives the message sent to UE A, P-CSCF equipment A sends the message to the PGW. Since the PGW has reassigned IP A to UE B, after receiving the message, the PGW will mistakenly send the message to UE B.

Contents of the invention

In order to overcome the defects of the prior art, the purpose of the embodiments of the present invention is to provide a method, device and system for allocating IP addresses, so as to prevent the PGW from sending messages to other UEs by mistake.

In a first aspect, an embodiment of the present invention provides a method for allocating IP addresses, including:

The PGW receives the registration request sent by the first UE;

The PGW allocates an IP address to the first UE;

The PGW receives the registration expiration time of the first UE sent by the P-CSCF device, where the registration expiration time of the first UE refers to the time when the registration of the first UE in the IMS expires;

The PGW stores the correspondence between the IP address and the registration expiration time;

The PGW releases the IP address when the first UE is deactivated;

The PGW receives a registration request sent by the second UE;

The PGW does not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives.

In a second aspect, an embodiment of the present invention provides a method for allocating IP addresses, including:

The PGW receives the registration request sent by the first UE;

The PGW allocates an IP address to the first UE;

The P-CSCF device receives the registration request sent by the first UE;

The P-CSCF device sends the registration expiration time of the first UE to the PGW, where the registration expiration time of the first UE refers to the time when the registration of the first UE in the IMS expires;

The PGW stores the correspondence between the IP address and the registration expiration time;

The PGW releases the IP address when the first UE is deactivated;

The PGW receives a registration request sent by the second UE;

The PGW does not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives.

In a third aspect, an embodiment of the present invention provides a PGW, including:

a receiving unit, configured to receive a registration request sent by the first user equipment UE;

a processing unit, configured to assign an IP address to the first UE after the receiving unit receives the registration request;

The receiving unit is further configured to receive the registration expiration time of the first UE sent by the P-CSCF device, wherein the registration expiration time of the first UE refers to the time when the registration of the first UE in the IMS expires;

The processing unit is also used to store the correspondence between the IP address and the registration expiration time received by the receiving unit;

The processing unit is further configured to release the IP address when the first UE is deactivated;

The receiving unit is further configured to receive a registration request sent by the second UE;

The processing unit is further configured to not assign the IP address to the second UE before the registration expiration time corresponding to the IP address arrives after the receiving unit receives the registration request sent by the second UE.

In a fourth aspect, an embodiment of the present invention provides a system for allocating IP addresses, including a PGW and a P-CSCF device, wherein,

The PGW is used to receive a registration request sent by the first UE, and assign an IP address to the first UE;

The P-CSCF is configured to receive the registration request sent by the first UE, and send the registration expiration time of the first UE to the PGW, wherein the registration expiration time of the first UE refers to the registration period of the first UE in the IMS full time

The PGW is also used to store the correspondence between the IP address and the registration expiration time, and release the IP address when the first UE is deactivated;

The PGW is also configured to receive a registration request sent by the second UE, and not assign the IP address to the second UE before the registration expiration time corresponding to the IP address arrives.

Embodiments of the present invention provide a method, device and system for allocating IP addresses. In this method, during the period after the UE's IP address is released and before the UE's registration expiration time arrives, the IP address once allocated to the UE will not be allocated to other UEs. Before the registration expiration time arrives, one IP address is only allocated to one UE, so that the PGW can prevent the PGW from sending the message sent to the UE to other UEs by mistake after the IP address of the UE is released.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

FIG. 1 is a system architecture diagram provided by an embodiment of the present invention;

FIG. 2 is a flow chart of a method for allocating IP addresses provided by an embodiment of the present invention;

FIG. 3 is a structural diagram of a PGW provided by an embodiment of the present invention;

FIG. 4 is a flow chart of a method for allocating IP addresses provided by an embodiment of the present invention;

FIG. 5 is a structural diagram of a system for assigning IP addresses provided by an embodiment of the present invention;

FIG. 6 is a structural diagram of a system for allocating IP addresses provided by an embodiment of the present invention;

FIG. 7 is a structural diagram of a PGW provided by an embodiment of the present invention;

Fig. 8 is a structural diagram of a PGW provided by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in FIG. 1 , it is a system architecture diagram provided by an embodiment of the present invention. Among them, UE 1 and 6 communicate with P-CSCF equipment 4 and 5 in IMS through PGW 2 and PCRF (policy and charging rules function, policy and charging rule function) equipment 3. When UE 1 initiates a registration request to PGW 2, PGW 2 allocates an IP address for UE 1 and notifies UE 1 of the allocated IP address. UE 1 can use this IP address to construct a new registration request, and send the new registration request to P-CSCF device 5. After receiving the registration request, the P-CSCF device 5 sends the registration expiration time (registration expiration time) of the UE 1 to the PGW 2, and the PGW 2 stores the correspondence between the IP address and the registration expiration time.

In the embodiment of the present invention, the registration expiry time of the UE refers to the time when the registration (registration) of the UE in the IMS expires. The registration of the UE in the IMS refers to the registration initiated by the UE in the IMS. When the UE's registration in the IMS expires, the UE needs to initiate re-registration. The embodiment of the present invention does not limit the specific expression form of the registration expiration time. In one of the possible implementations, the registration expiration time may be a time period, which is used to indicate that after the time period expires, the UE's registration in the IMS will expire, and the UE needs to initiate re-registration; in another In a possible implementation manner, the registration expiry time may be a time point, which is used to indicate that when the time indicated by the time point arrives, the registration of the UE in the IMS will expire, and the UE needs to initiate a re-registration.

When UE 1 is deactivated (such as deletion of VoLTE bearer due to SRVCC (single radio voice call continuity, single radio voice call continuity) handover), PGW 2 releases the IP address allocated for UE 1 so that other UEs can use it IP address.

When PGW 2 receives the registration request sent by UE 6, before PGW 2 allocates the previously released IP address to UE 6, PGW 2 needs to check whether the registration expiration time corresponding to the IP address has arrived. If the registration expiration time has arrived, PGW 2 can allocate the IP address for UE 6. If the registration expiration time has not yet arrived, PGW 2 cannot allocate the IP address to UE 2. At this time, PGW 2 can allocate other IP addresses to UE 2, or not allocate any IP address to UE 2. IP address.

It should be noted that, in the embodiment of the present invention, UEs (such as UEs 1 and 6 in FIG. 1 ) may be terminal devices such as mobile phones, tablet computers, or netbooks. The P-CSCF equipment includes a memory and a processor, and the processor in the P-CSCF equipment can implement the function of agent-call session control. The PCRF device includes a memory and a processor, and the processor in the PCRF device can implement the functions of policies and charging rules.

As shown in FIG. 2, it is a method for allocating IP addresses provided by an embodiment of the present invention. The method is executed by a PGW. For example, the method may be executed by PGW 2 in FIG. 1. The methods shown in Figure 2 include:

Step 201: Receive a registration request sent by a first UE.

The first UE may be UE 1 in FIG. 1 .

Step 202: Allocate an IP address for the first UE.

Optionally, after the PGW allocates the IP address to the first UE, the PGW may send a registration response to the first UE, where the registration response carries the IP address allocated to the first UE.

Optionally, the registration response may also carry the IP address of the P-CSCF, so that the UE initiates a registration request to the P-CSCF.

Step 203: Receive the registration expiry time of the first UE sent by the P-CSCF device, wherein the registration expiry time of the first UE refers to the time when the registration (registration) of the first UE in the IMS expires.

In the embodiment of the present invention, the P-CSCF device receives the registration request sent by the first UE before sending the registration expiration time.

The PGW may directly receive the registration expiration time sent by the P-CSCF device, or may receive the registration expiration time sent by the P-CSCF device through the PCRF device.

It should be noted that the P-CSCF device may be the P-CSCF device 4 or 5 in FIG. 1 . The registration expiry time can be a period of time, or a point in time. When the registration expiry time expires, the registration of UE 1 in the IMS expires. For details, please refer to the above-mentioned explanation, which will not be repeated here. .

Step 204: Store the corresponding relationship between the IP address assigned to the first UE and the registration expiration time.

Step 205: When the first UE is deactivated, release the IP address allocated for the first UE.

Deactivating the first UE specifically refers to deactivating the bearer of the first UE, that is, releasing the bearer of the first UE. When the bearer of the first UE is released, the IP address allocated for the first UE will be released, so that the IP address can be used by other UEs.

Step 206: Receive a registration request sent by the second UE.

The second UE may be UE 6 in FIG. 1 .

Step 207: Before the registration expiry time corresponding to the released IP address arrives, the released IP address is not allocated to the second UE.

Step 207 may specifically include two situations. The first situation is that the PGW allocates an IP address other than the released IP address to the second UE. In this case, the PGW will allocate an IP address to the second UE, but the IP address allocated is different from the IP address previously allocated to the first UE. The second situation is that the PGW does not allocate any IP address to the second UE.

In step 203, when the PGW receives the registration expiration time sent by the P-CSCF device through the PCRF device, step 203 may be implemented in the following manner:

The P-CSCF device sends an authentication authorization request (AA-Reqest, AAR) to the PCRF device, and the AAR carries the registration expiration time, and the PCRF device sends a re-authentication request (Re-Auth-Request, RAR) to the PGW , the RAR carries the registration expiration time.

In the method provided by the embodiment of the present invention, during the period after the UE's IP address is released and before the UE's registration expiration time arrives, the IP address once allocated to the UE will not be allocated to other UEs, Therefore, it is ensured that one IP address is only allocated to one UE before the registration expiration time is reached, thereby preventing the PGW from mistakenly sending the message sent to the UE to other UEs after the UE's IP address is released.

As shown in FIG. 3 , a PGW is provided for an embodiment of the present invention, and the PGW includes a memory 301 and a processor 302 . The memory 301 stores a series of executable program codes, and the processor 302 reads the executable program codes in the memory 301 to achieve the purpose of the present invention. Specifically, the processor 302 is configured to execute the method shown in FIG. 2 . For detailed description, reference may be made to the embodiment shown in FIG. 2 , and details are not repeated here.

As shown in Figure 4, a method for allocating IP addresses under the system architecture shown in Figure 1 provided for the embodiment of the present invention includes:

Step 401: UE 1 sends a registration (register) request to PGW 2.

UE 1 can send a registration request to PGW 2 through S-GW (serving gateway, serving gateway) or SGSN (gateway general packet radio system support node, gateway general packet radio system support node) to register UE 1 with PGW 2.

Step 402: PGW 2 allocates an IP address for UE 1.

Step 403: PGW 2 sends a credit control request (credit control request, CCR) to PCRF device 3, and the credit control request carries the IP address.

Step 404: PCRF device 3 sends a credit control answer (credit control answer, CCA) to PGW 2.

Through steps 403 and 404, PGW 2 establishes a Gx session between PGW 2 and PCRF device 3.

Optionally, both the CCR and the CCA carry the session identifier (session id) of the Gx session.

Step 405: PGW 2 sends a registration response to UE 1, and the registration response carries the IP address allocated for UE 1.

It should be noted that, this embodiment of the present invention does not limit the sequence of execution between step 405 and step 403 , and step 405 may be executed before step 403 or after step 403 .

Step 406: UE 1 sends a registration (register) request to P-CSCF device 5.

The registration request sent by UE 1 to P-CSCF device 5 may carry the registration expiration time of UE 1. The registration request in step 406 is a registration request based on the Session Initiation Protocol (Session Initiation Protocol, SIP). As an example but not a limitation, the expires field of the Contact header field in the registration request may be used to indicate the registration expiration time.

The registration request sent by UE 1 to P-CSCF device 5 carries the IP address assigned by PGW 2 to UE 1 and the IP address of P-CSCF device 5. The IP address of P-CSCF device 5 can be determined by PGW 2, and sent to UE 1 by PGW 2 through the registration response in step 405, or UE 1 can obtain the IP address assigned by PGW 2 to UE 1 according to PGW 2 The assigned IP address is determined.

For example, UE 1 or PGW 2 can pre-store a mapping table between the IP address of the UE and the IP address of the P-CSCF device, and UE 1 or PGW 2 can determine the P-CSCF device corresponding to the IP address of the UE according to the mapping table the address of.

Step 407: The P-CSCF device 5 sends an authentication authorization request (AAR) to the PCRF device 3, and the authentication authorization request carries the registration expiration time of the UE 1.

The authentication authorization request also carries the IP address allocated for UE1.

As an example and not a limitation, the expires AVP (attribute-value pair, attribute-value pair) can be extended in the AAR, and the extended AVP is used to indicate the registration expiration time, as shown below:

Step 408: PCRF device 3 sends a re-authentication request (RAR) to PGW 2, and the re-authentication request carries the registration expiration time of UE 1.

The re-authentication request also carries the IP address allocated for UE1.

As an example and not a limitation, the expires AVP can be extended in RAR, and the extended AVP is used to indicate the registration expiration time, as follows:

Step 409: PGW 2 stores the corresponding relationship between the IP address allocated for UE 1 and the registration expiration time of UE 1.

For example, PGW 2 may store the corresponding relationship between the IP address assigned to UE 1 and the registration expiration time of UE 1 in a record of a table (table), as shown in Table 1.

Table 1:

UE's IP address UE's registration expiration time 180.149.132.40 3600 seconds

Step 410: PGW 2 sends a re-authentication response (Re-Auth-Answer, RAA) to PCRF device 3.

This embodiment of the present invention does not limit the execution order between step 409 and step 410 , and step 410 may be executed before step 409 or after step 409 .

Step 411: PCRF device 3 sends an authentication authorization response (AA-Answer, AAA) to P-CSCF device 5 .

Through steps 407 and 411 , the P-CSCF device 5 establishes an Rx session between the P-CSCF device 5 and the PCRF device 3 .

Optionally, both the AAR and the AAA carry the session identifier (session id) of the Rx session.

The PCRF device 3 can associate the Rx session between the P-CSCF device 5 and the PCRF device 3 with the Gx session between the PGW 2 and the PCRF device 3 according to the IP address allocated to the UE 1.

Step 412: When UE 1 is deactivated, PGW 2 releases the IP address allocated for UE 1.

For example, when UE 1 switches from a 4G network to a 3G network, the SGSN will initiate a request to PGW 2 to delete the VoLTE bearer. After deleting the VoLTE bearer, PGW 2 will notify PCRF device 3 to delete the Gx between PGW 2 and PCRF device 3. session. When PGW 2 deletes the VoLTE bearer, PGW 2 will release the IP address allocated to UE 1, so that the IP address can be allocated to other UEs in the future.

Step 413: PGW 2 receives the registration request sent by UE 6.

Step 414: Before the PGW 2 determines to allocate the released IP address to the UE 6, it first needs to check whether the registration expiration time corresponding to the released IP address has arrived. If the registration expiration time has arrived, go to step 415 , otherwise go to step 416 .

Step 415: PGW 2 assigns the released IP address to UE 6.

Of course, when the registration expiration time has arrived, PGW 2 can also allocate other IP addresses to UE 6 except the IP address previously allocated to UE 1.

Step 416: PGW 2 does not assign the released IP address to UE 6.

The fact that PGW 2 does not allocate the released IP address to UE 6 specifically means that PGW 2 may allocate other IP addresses to UE 6 than the released IP address, or may not allocate any IP address to UE 6.

In this embodiment of the present invention, the registration expiry time of UE 1 may be a period of time (such as 30 minutes), or a point in time (such as 1:1:1:1 on January 1, 2000). When the registration expiration time is a time point, in step 414, PGW 2 can check whether the time point has arrived, if the current time has exceeded the time point, then PGW 2 can determine that the registration expiration time has arrived. When the registration expiration time is a time period, PGW 2 can start a timer when releasing the IP address allocated for UE 1, and set the time interval of the timer as the time interval indicated by the registration expiration time (such as 30 minutes), when the time interval of the timer expires, PGW 2 determines that the registration expiration time has arrived.

It is worth noting that when the registration expiration time is a time period, PGW 2 can also start a timer when receiving the re-authentication request carrying the registration expiration time sent by PCRF device 3, and set the timer The time interval is set as the time interval (such as 30 minutes) represented by the registration expiration time, and when the time interval of the timer expires, PGW 2 determines that the registration expiration time has arrived.

Through the method provided by the embodiment of the present invention, it can be guaranteed that after the IP address of the UE is released and before the registration in the IMS expires, the IP address allocated to the UE will no longer be allocated to other UEs, thereby preventing the PGW from In the segment, the message sent to this UE is mistakenly sent to other UEs.

As shown in FIG. 5, it is a system for allocating IP addresses provided by an embodiment of the present invention, and the system includes a PGW 501 and a P-CSCF device 502.

The PGW 501 is configured to receive a registration request sent by the first UE, and assign an IP address to the first UE;

The P-CSCF device 502 is used to receive the registration request sent by the first UE, and send the registration expiration time of the first UE to the PGW 501, wherein the registration expiration time of the first UE refers to the registration period of the first UE in the IMS full time

The PGW 501 is also used to store the correspondence between the IP address and the registration expiration time, and release the IP address when the first UE is deactivated;

The PGW 501 is also configured to receive a registration request sent by the second UE, and not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives.

The fact that the PGW 501 does not allocate the IP address to the second UE means that the PGW 501 allocates an IP address other than the IP address to the second UE, or does not allocate any IP address to the second UE.

In an embodiment of the present invention, the system may further include a PCRF device 603, as shown in FIG. 6 . The P-CSCF device 502 may send the registration expiration time to the PGW 501 through the PCRF device 603.

The PCRF device 603 is configured to receive the registration expiration time sent by the P-CSCF device 502, and send the registration expiration time to the PGW 501.

As an example but not a limitation, the PCRF device 603 can be used to receive the AA-Reqest sent by the P-CSCF device 502, the AA-Reqest carries the registration expiration time, and send a Re-Auth-Request to the PGW 501, the Re-Auth- Request carries the registration expiration time.

It should be noted that the PGW shown in FIG. 3 can be applied in this system.

As shown in FIG. 7, it is another PGW provided by the embodiment of the present invention. The PGW shown in FIG. 7 can be applied to the systems shown in FIG. 5 and FIG. 6 . The PGW shown in Figure 7 includes:

a receiving unit 701, configured to receive a registration request sent by the first UE;

The processing unit 702 is configured to assign an IP address to the first UE after the receiving unit 701 receives the registration request;

The receiving unit 701 is further configured to receive the registration expiration time of the first UE sent by the P-CSCF device, wherein the registration expiration time of the first UE refers to the time when the registration (registration) of the first UE in the IMS expires;

The processing unit 702 is also configured to store the correspondence between the IP address and the registration expiration time received by the receiving unit 701;

The processing unit 702 is further configured to release the IP address when the first UE is deactivated;

The receiving unit 701 is also configured to receive a registration request sent by the second UE;

The processing unit 702 is further configured to not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives after the receiving unit 701 receives the registration request sent by the second UE.

Wherein, the processing unit 702 does not allocate the IP address to the second UE specifically means that the processing unit 702 allocates an IP address other than the IP address to the second UE, or does not allocate any IP address to the second UE.

In an implementation manner of the embodiment of the present invention, the receiving unit 701 receives, through the PCRF device, the registration expiration time of the first UE sent by the P-CSCF device.

In an implementation manner of the embodiment of the present invention, the PGW further includes a sending unit 803, as shown in FIG. 8 . The sending unit 803 is configured to send a registration response to the first UE, where the registration response carries the IP address allocated for the first UE by the processing unit 702 .

Wherein, the registration response sent by the sending unit 803 may also carry the IP address of the P-CSCF device.

Embodiments of the present invention provide a method, device and system for allocating IP addresses. In this method, during the period after the UE's IP address is released and before the UE's registration expiration time arrives, the IP address once allocated to the UE will not be allocated to other UEs. Before the registration expiration time arrives, one IP address is only allocated to one UE, so that the PGW can prevent the PGW from sending the message sent to the UE to other UEs by mistake after the IP address of the UE is released.

It can be known from the above description of the implementation manners that those skilled in the art can clearly understand that the present invention can be implemented by hardware, firmware, or a combination thereof. When implemented in software, the functions described above may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example but not limitation: computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or may be used to carry or store information in the form of instructions or data structures desired program code and any other medium that can be accessed by a computer. also. Any connection can suitably be a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable , fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, wireless, and microwave are included in the fixation of the respective media. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disc, and Blu-ray disc, where discs usually reproduce data magnetically, and discs Lasers are used to optically reproduce the data. Combinations of the above should also be included within the scope of computer-readable media.

It should be noted that each embodiment in this specification is described in a progressive manner, the same and similar parts of each embodiment can be referred to each other, and each embodiment focuses on the differences from other embodiments. place. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the specific function execution process of each unit can refer to the part of the description of the method embodiment. The device embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place , or can also be distributed to multiple network elements. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. It can be understood and implemented by those skilled in the art without creative effort.

In a word, the above descriptions are only preferred embodiments of the technical solutions of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (21)

1. A method for distributing an Internet Protocol IP address, characterized in that, comprising: The packet data network gateway PGW receives the registration request sent by the first user equipment UE; The PGW assigns an IP address to the first UE; The PGW receives the registration expiration time of the first UE sent by the proxy-call session control function P-CSCF device, where the registration expiration time of the first UE refers to the registration expiration time of the first UE in the IP multimedia the time at which the registration in the system IMS expires; The PGW stores the correspondence between the IP address and the registration expiration time; The PGW releases the IP address when the first UE is deactivated; The PGW receives a registration request sent by the second UE; The PGW does not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives. 2. The method according to claim 1, wherein the not allocating the IP address to the second UE comprises: The PGW assigns an IP address other than the IP address to the second UE; or, The PGW does not allocate any IP address to the second UE. 3. The method according to claim 1 or 2, wherein the PGW receives the registration expiration time sent by the P-CSCF device, comprising: The PGW receives the registration expiration time sent by the P-CSCF through the policy and charging rule function PCRF device. 4. The method according to claim 3, wherein the PGW receives, through the PCRF device, the registration expiration time sent by the P-CSCF device, comprising: The P-CSCF device sends an authentication authorization request AA-Reqest to the PCRF device, and the AA-Request carries the registration expiration time; The PCRF device sends a re-authentication request Re-Auth-Request to the PGW, and the Re-Auth-Request carries the registration expiration time. 5. The method according to any one of claims 1-4, wherein after the PGW assigns the IP address to the first UE, the method further comprises: The PGW sends a registration response to the first UE, where the registration response carries the IP address allocated by the PGW to the first UE. 6. The method according to claim 5, wherein the registration response also carries the IP address of the P-CSCF device. 7. A method for allocating Internet Protocol IP addresses, comprising: The packet data network gateway PGW receives the registration request sent by the first user equipment UE; The PGW assigns an IP address to the first UE; The proxy-call session control function P-CSCF device receives the registration request sent by the first UE; The P-CSCF device sends the registration expiration time of the first UE to the PGW, wherein the registration expiration time of the first UE refers to the registration of the first UE in the IP Multimedia Subsystem IMS the time of expiry; The PGW stores the correspondence between the IP address and the registration expiration time; The PGW releases the IP address when the first UE is deactivated; The PGW receives a registration request sent by the second UE; The PGW does not allocate the IP address to the second UE before the registration expiration time corresponding to the IP address arrives. 8. The method according to claim 7, wherein the not allocating the IP address to the second UE comprises: The PGW assigns an IP address other than the IP address to the second UE; or, The PGW does not allocate any IP address to the second UE. 9. The method according to claim 7 or 8, wherein the P-CSCF device sends the registration expiration time to the PGW, including: The P-CSCF device sends the registration expiration time to the policy and charging rule function PCRF device; The PCRF device sends the registration expiration time to the PGW. 10. The method according to claim 9, wherein the P-CSCF device sends the registration expiration time to the PCRF device, comprising: The P-CSCF device sends an authentication authorization request AA-Reqest to the PCRF device, and the AA-Request carries the registration expiration time; The PCRF device sends the registration expiration time to the PGW, including: The PCRF device sends a re-authentication request Re-Auth-Request to the PGW, and the Re-Auth-Request carries the registration expiration time. 11. The method according to any one of claims 7-10, wherein after the PGW allocates an IP address to the first UE, the method further comprises: The PGW sends a registration response to the first UE, where the registration response carries the IP address allocated by the PGW to the first UE. 12. The method according to claim 11, wherein the registration response also carries the IP address of the P-CSCF device. 13. A packet data network gateway PGW, characterized in that, comprising: a receiving unit, configured to receive a registration request sent by the first user equipment UE; a processing unit, configured to assign an IP address to the first UE after the receiving unit receives the registration request; The receiving unit is further configured to receive the registration expiry time of the first UE sent by the proxy-call session control function P-CSCF device, where the registration expiry time of the first UE refers to the first UE the time at which the registration in the IP Multimedia Subsystem IMS expires; The processing unit is further configured to store the correspondence between the IP address and the registration expiration time received by the receiving unit; The processing unit is further configured to release the IP address when the first UE is deactivated; The receiving unit is further configured to receive a registration request sent by the second UE; The processing unit is further configured to not allocate the IP address to the Second UE. 14. The PGW according to claim 13, wherein the processing unit is specifically configured to: after the receiving unit receives the registration request sent by the second UE, during the registration period corresponding to the IP address Before the full time expires, assign an IP address other than the IP address to the second UE, or assign no IP address to the second UE. 15. The PGW according to claim 13 or 14, wherein when receiving the registration expiration time, the receiving unit is specifically configured to receive the P-CSCF device through the policy and charging rule function PCRF device The registration expiration time sent. 16. The PGW according to any one of claims 13-15, wherein the PGW further comprises: A sending unit, configured to send a registration response to the first UE, where the registration response carries the IP address assigned by the processing unit to the first UE. 17. The PGW according to claim 16, wherein the registration response also carries the IP address of the P-CSCF device. 18. A system for distributing Internet Protocol IP addresses, characterized in that it comprises a packet data network gateway PGW and an agent-call session control function P-CSCF device, wherein, The PGW is configured to receive a registration request sent by a first user equipment UE, and assign an IP address to the first UE; The P-CSCF is configured to receive the registration request sent by the first UE, and send the registration expiration time of the first UE to the PGW, where the registration expiration time of the first UE refers to the The time at which the registration of the first UE in the IP Multimedia Subsystem IMS expires; The PGW is also used to store the correspondence between the IP address and the registration expiration time, and release the IP address when the first UE is deactivated; The PGW is further configured to receive a registration request sent by the second UE, and not allocate the IP address to the second UE before a registration expiration time corresponding to the IP address arrives. 19. The system according to claim 18, wherein the PGW is specifically configured to allocate an IP address other than the IP address to the second UE before the registration expiration time corresponding to the IP address arrives. other IP addresses, or do not assign any IP address to the second UE. 20. The system according to claim 18 or 19, wherein the system further comprises a policy and charging rule function PCRF device; The PCRF device is configured to receive the registration expiration time sent by the P-CSCF device, and send the registration expiration time to the PGW. 21. The system according to claim 20, wherein the PCRF device is specifically configured to receive the authentication authorization request AA-Reqest sent by the P-CSCF device, the AA-Request carrying the registration expiration time, and send a re-authentication request Re-Auth-Request to the PGW, where the Re-Auth-Request carries the registration expiration time.