WO2011072540A1

WO2011072540A1 - Ip address assignment method and gateway

Info

Publication number: WO2011072540A1
Application number: PCT/CN2010/076989
Authority: WO
Inventors: 胡玉胜; 林青春; 张晋兴
Original assignee: 华为技术有限公司
Priority date: 2009-12-17
Filing date: 2010-09-16
Publication date: 2011-06-23
Also published as: CN101764856B; CN101764856A

Abstract

An IP address assignment method and the corresponding gateway are provided in the embodiments of the present invention, for solving the problem of bad fault tolerance or dependence on steady operation of extra servers when assigning IP addresses to mobile terminals. Said method includes: acquiring the unique identification code of the mobile terminal (S101); regarding the unique identification field in the unique identification code or the unique identification code as the mapping variable, mapping the mapping variable to the rear three sections of the IP address (S102); reading out the home sub-network number of the unique identification code from the configuration information, regarding the sub-network number as the prefix of the IP address and combining it and the rear three sections of the IP address together as the IP address (S103); and assigning the combined IP address to the mobile terminal (S104). The IP address assignment method in the present invention has better robust and quick IP address assignment speed, without consuming the time for releasing the IP address pool. In addition, the IP addresses generated by the mapping mode in the present invention are all unique, thus removing the possible conflict during assigning or releasing the IP address.

Description

The present invention claims the priority of the Chinese patent application filed on December 17, 2009, the Chinese Patent Office, the application number is 200910252490.3, and the invention name is "an IP address allocation method and gateway." The entire contents thereof are incorporated herein by reference.

The invention relates to the field of data service of a wireless core network, an IP address allocation method and a gateway. Background technique

With the popularity of mobile terminals and the improvement of people's living standards, more and more users are accustomed to using the mobile terminals supporting General Packet Radio Service (GPRS) to access the Internet. How to assign an IP address to a mobile terminal quickly and without conflict is an important problem that GPRS needs to solve. The IP pool allocation method, and the other is the foreign IP address allocation method. The local IP address pool allocation method is relatively simple, that is, the gateway GPRS support node (GGSN) allocates an IP address to the mobile terminal in the shared local IP address pool, and the IP address used by the mobile terminal after the mobile terminal goes offline. The address can be assigned to other mobile terminals that are subsequently online. That is to say, the local IP address pool allocation method is characterized in that the IP address assigned by the mobile terminal every time it goes online may not be the same, and may occur under abnormal conditions: The external server records the IP address used by the mobile terminal A, when After the mobile terminal A goes offline, the IP address originally assigned to the mobile terminal A is again assigned to other mobile terminals, such as the mobile terminal B, thereby causing the external server to erroneously transmit the message that should originally be sent to the mobile terminal A to Mobile terminal B.

As for the foreign IP address allocation method, the authentication authorization/authorization/accounting (AAA, Authentication Authorization Accounting) server assigns an IP address and a dynamic host configuration protocol (DHCP) to assign an IP address. This method of assigning a foreign IP address is a mobile terminal passing an GGSN to an external server (for example, an AAA server or a DHCP server). Sending a request for assigning an IP address to the mobile terminal, after receiving the request, the external server allocates an idle IP address to the mobile terminal from the configured IP address pool and returns it to the mobile terminal through the GGSN.

Because the external IP address allocation method needs to rely on the stable operation of the external server (AAA server or DHCP server), once the external server is unstable, it will directly affect the allocation of the IP address of the mobile terminal, which in turn affects the user's service usage. Summary of the invention

The embodiments of the present invention provide an IP address allocation method and a corresponding gateway, which are intended to solve the problem of poor fault tolerance or relatively stable operation of an external server when assigning an IP address to a mobile terminal.

An IP address allocation method includes: acquiring a unique identification code of a mobile terminal; mapping the mapping variable to a mapping variable by using a unique identification field or the unique identification code in the unique identification code as a mapping variable

The last three segments of the IP address; the subnet number to which the unique identification code belongs is read from the configuration information, and the prefix with the subnet number being the IP address is combined with the last three segments of the IP address to form an IP address; Assigning the IP address obtained by the combination to the mobile terminal.

A gateway, comprising: an obtaining module, configured to obtain a unique identifier of the mobile terminal; and a mapping module, configured to use the unique identifier field in the unique identifier code of the mobile terminal or the unique identifier as a mapping variable, and the mapping variable Mapping to the last three segments of the IP address; the IP address combination module, configured to read, from the configuration information, the subnet number to which the unique identifier is assigned, where the subnet number is a prefix of the IP address and the IP address The last three segments are combined into an IP address; an allocation module is configured to allocate an IP address obtained by combining the IP address combination modules to the mobile terminal.

In the embodiment of the present invention, the unique identifier field in the unique identifier code of the mobile terminal is used as a mapping variable, and the mapping variable is mapped to the last three segments of the IP address, and the subnet number to which the unique identifier of the mobile terminal belongs is used as the prefix of the IP address. The IP address is combined with the last three segments of the mapped IP address. Since the IP address generated by the mapping method in the embodiment of the present invention is generated by the local GGSN, and does not depend on the stable operation of an external server (for example, an AAA server or a DHCP server), the IP address allocation is performed. The method has better robustness, and does not need to release the IP address pool as in the prior art, and the IP address is allocated quickly. In addition, for each mobile terminal, the IP generated by the mapping method of the present invention is used. The addresses are unique, thus eliminating address conflicts that may exist when assigning or releasing IP addresses. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any inventive labor.

1 is a schematic flowchart of a basic method for generating an IP address according to an embodiment of the present invention;

3 is a schematic diagram of a modified discontinuous IP address number segment provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a basic logical structure of a gateway according to an embodiment of the present invention. detailed description

BRIEF DESCRIPTION OF THE DRAWINGS The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without the creative work are all within the scope of the present invention.

Referring to FIG. 1, a schematic flowchart of a method for generating an IP address according to an embodiment of the present invention includes the following steps:

S101. Obtain a unique identification code of the mobile terminal.

The mobile terminal will provide a service GPRS support node (SGSN, Serving) before accessing the Internet. The GPRS Support Node sends an activation message, for example, a Packet Data Protocol (PDP) context request, which is forwarded by the SGSN to the GGSN, and the GGSN acquires the unique identification code of the mobile terminal from the activation message. In the embodiment of the present invention, the unique identification code of the mobile terminal may be an International Mobile Subscriber Identity (IMSI), an International Mobile Equipment Identity (IMEI), or other code that can uniquely identify the mobile terminal. Word, etc.

S102: The mapping variable is mapped to the last three segments of the IP address by using a unique identifier field or a unique identifier in the unique identifier of the mobile terminal as a mapping variable.

Since the IMSI of which number segment is considered as the number segment allowed to be accessed when the technical solution of the present invention is specifically implemented, the system administrator can set a range of number segments. When the GGSN receives the activation message of the mobile terminal, it first determines whether the IMSI of the mobile terminal is within the set number range.

If the IMSI of the mobile terminal is in the range of the set number segment, the unique identifier field in the unique identifier of the mobile terminal, for example, the mobile station authentication number (MSIN, Mobile Station Identity Number) field in the IMSI is used as a mapping variable. The mapping variable is mapped to the last three segments of the IP address, including:

51021. Select three mapping parameters for each of the last three segments of the IP address.

In the case of IPv4, the existing IP address is 32 bits, and each 8 bits is a section (or a segment). In the embodiment of the present invention, the last three segments of the IP address are: the 16th to 23rd bits are the first segment, and the 8th and 15th bits are the second segment, the 0th to the 7th bits. A mapping parameter can be selected for each of these segments, and one mapping parameter can remain unchanged for different MSINs.

51022, one of the MSIN and one of the three mapping parameters is used as a mapping factor, and three operation operations are performed on the mapping factor to obtain three operation results, and the three operation results are used as the last three segments of the IP address. Still taking IPv4 as an example, considering that the first segment of the IP address (bits 16 to 23) is converted to a corresponding decimal range between 0 and 255, 255x254 and 255 can be used as the first mapping parameter to execute (MSIN/ 255X254) The operation result obtained after the operation operation of %255 is taken as the first segment of the last three segments of the IP address, where "x", "/" and "%" are respectively the multiplication operation, the division operation, and the modulo operation. Similarly, considering that the second segment of the IP address (bits 8 to 15) is converted to a corresponding decimal range between 0 and 255, 254 and 255 can be used as the first mapping parameter to execute (MSIN/254). The operation result obtained after the %255 operation operation is taken as the second segment of the last three segments of the IP address.

For the third segment of the IP address (bits 0 to 7), the legal range for conversion to decimal should be between 1 and 254. If the "modulo" operation is simply performed, that is, the operation of MSIN/%254 is performed. You may get an operation result of 0 or 255, which is not within the legal range. Therefore, for the third segment of the IP address, in the embodiment of the present invention, 254 can be used as the third mapping parameter, and the operation result obtained after the (MSIN%255) + 1 operation operation is used as the first segment of the IP address.

Since the MSIN is a unique identification field in the international mobile subscriber identity of the mobile terminal, for each mobile terminal, the last three segments of the mapped IP address are also unique, and will not be the last three of the IP addresses of other mobile terminals. Segment conflicts.

It should be noted that although the present invention uses the MSIN field in the international mobile subscriber identity as a mapping variable, and performs operations operations such as adding, subtracting, multiplying, dividing, and modulating on the MSIN and the mapping parameters, the techniques in the art. Personnel should be able to understand that there are other mapping variables to choose from, and there are other operations that can be used as operations to implement the mapping, as long as the unique identification code of the mobile terminal or the field in the unique identification code is mapped. The last three segments of the IP address are unique, and the present invention is not limited.

Of course, in order to achieve simple implementation of the technical solution of the present invention, a linear mapping (as shown in the above embodiment) may be used as a preferred mapping manner, such that for a serial number of consecutive IMSIs, after linear mapping The last three segments of the obtained IP address are consecutive.

S103. The subnet number to which the unique identifier is assigned is read from the configuration information, and the prefix with the subnet number being the IP address is combined with the last three segments of the IP address to form an IP address.

For multiple mobile terminals accessing the Internet, the unique identification code number, such as the IMSI number segment, needs to be planned into a certain subnet. That is, the network management personnel plan the IMSI number segment in advance, and clarify the child to which the unique identification code of the mobile terminal belongs. The network number is stored in the GGSN in the form of configuration information. In the embodiment of the present invention, the prefix of the IP address (ie, the 24th to 31st bits of the IP address in the IPv4 address) may be obtained by using the mapping, and only the subnet number to which the unique identification code belongs is read from the configuration information. The subnet number is a prefix of the IP address, and is combined with the last three segments of the IP address obtained by mapping in S102 to constitute an IP address.

In a practical application, if multiple mobile terminals in a certain subnet are planned, the unique identification code number segments formed by the unique identification codes may not be consecutive to each other, so even after linear mapping, prefix is obtained. The IP address number segments formed by the IP addresses are not continuous with each other. As shown in FIG. 2, the IMSI number segment 1 is mapped into an IP address number segment 1, for example, 192.148.125.2 to 192.148.125.96, and the IMSI number segment 2 is mapped into an IP address number segment 2, for example, 192.148.125.100 to 192.148.125.213; IP address number segment 1 IP address termination endpoint 192.148.125.96 and IP address number segment 2 IP address start endpoint 192.148.125.100 has a difference of 4 (100 - 96 = 4), ie IP address number segment 1 and IMSI Segment 2 is not continuous.

In order to facilitate network planning or for other purposes (for example, it is desirable to save IP address resources, do not want IP addresses to be exhausted as soon as possible), in the embodiment of the present invention, discontinuous uniqueness is formed for multiple mobile terminal unique identification codes. After the identification code number segment is linearly mapped to obtain a discontinuous IP address number segment, the discontinuous IP address number segment may be corrected. The specific modification method is: an IP address based on the endpoint of the IP address number segment, The reference IP address is increased by an offset (Offset). As for the size of the offset, it may not be fixed, mainly based on the difference between the endpoints of the discontinuous IP address number segment. The basic principle is: After increasing the offset, the modified IP address number segment constitutes a continuous IP address number segment.

for example. It is assumed that IMSI (1) and IMSI (95) constitute the IMSI number segment IMSI (3-no), IMSI (m) and IMSI (234) constitute the IMSI number segment IMSI (121-234), and the mapped IP address number segment They are the first IP address number segment (IP address number segment 1) 192.148.125.2 ~ 192.148.125.96 and the second IP address number segment (IP address number segment 2) 192.148.125.100~ 192.148.125.213. One endpoint (terminating IP address) of the first IP address number segment is 192.148.125.96, and one endpoint (starting IP address) of the second IP address number segment is 192.148.125.100. Obviously, the two IP address numbers are not consecutive. If the IP address is directly allocated according to the mapped IP address number, the network planning is inconvenient and the address resources are wasted.

According to the modification mode and the correction principle provided by the embodiment of the present invention, the endpoint 192.148.125.100 of the second IP address number segment can be increased by an offset (as shown in FIG. 3), for example, an offset of 192.148.125.100 is added. A quantity - 3, that is, an operation of 192.148.125.100 + ( - 3 ) for 192.148.125.100, making it 192.148.125.97. Thus, the second IP address number segment becomes 192.148.125.97~192.148.125.213, and its starting IP address becomes 192.148.125.97, immediately following the termination IP address of the first IP address number segment 192.148.125.96, two The IP address number segment becomes continuous.

Of course, if it is not a linear mapping, even if the unique identification code number segments composed of the unique identification code (for example, IMSI) are continuous, after the nonlinear mapping, the IP address obtained by adding the prefix constitutes The discontinuous IP address number segment is also not contiguous. In this case, the method of increasing the offset can be used to modify the non-contiguous IP address number segment to a continuous IP address number segment. The specific method is not described here.

S104. Assign the IP address obtained by combining in S103 to the mobile terminal. Does not depend on the stable operation of an external server (for example, an AAA server or a DHCP server) Therefore, the IP address allocation method has better robustness, does not need to release the IP address pool as in the prior art, and allocates an IP address quickly. In addition, for each mobile terminal, the mapping of the present invention is adopted. The IP addresses generated by the mode are unique, thus eliminating the address conflicts that may exist when assigning or releasing IP addresses.

Referring to FIG. 4, a schematic diagram of a basic logical structure of a gateway according to an embodiment of the present invention is provided. For convenience of explanation, only parts related to the embodiment of the present invention are shown, and the illustrated functional modules/units may be software modules/units, hardware modules/units, or modules/units in which hardware and software are combined. The gateway may be a GGSN or a router in the GPRS system, which specifically includes the following functional modules/units.

The mapping module 401 is configured to map the mapping variable to the last three segments of the IP address by using a unique identifier field in the unique identifier of the mobile terminal as a mapping variable, including:

Parameter selection unit 4011, configured to select three mapping parameters;

The operation unit 4012 is configured to use one of the three mapping parameters selected by the MSIN and the parameter selection unit 4011 as a mapping factor, and perform three operation operations on the mapping factor to obtain three operation results, three operations. The result is the last three segments of the IP address.

The IP address combination module 402 is configured to use the subnet number to which the mobile terminal unique identification code belongs as the IP address prefix, and combine with the last three segments of the IP address mapped by the mapping module 401 to form an IP address.

As mentioned above, since in a practical application, a plurality of mobile terminals in a certain subnet are planned, the unique identification code number segments formed by the unique identification codes may not be consecutive to each other. In this way, even after the mapping by the mapping module 401, the IP address number segment formed by the IP address obtained by adding the prefix (the subnet number to which the mobile terminal unique identification code belongs) is not continuous with each other; or, multiple The unique identification code number segments of the mobile terminal are continuous with each other, but because the mapping mode of the mapping module 401 is not a linear mapping, the IP address number segments formed by the IP addresses obtained by the prefix are not continuous with each other. .

An allocating module 403, configured to allocate an IP address obtained by combining the IP address combining module 402 to the mobile terminal End.

In the above case, in order to facilitate network planning or for other purposes (for example, it is desirable to save IP address resources, do not want the IP address to be exhausted as soon as possible), in this embodiment, the gateway may further include: an IP address number segment. The correcting module 404, when the unique identification code number segment formed by the unique identification code of the mobile terminal is mapped to obtain a discontinuous IP address number segment, the discontinuous IP address number segment is corrected to become a continuous IP address. The segment is then assigned to the mobile terminal by the allocation module 403. The method of correcting the discontinuous IP address number segment may be an IP address based on the endpoint of the IP address number segment, and the reference IP address is increased by an offset (Offset). As for the size of the offset, it may not be fixed, mainly based on the difference between the endpoints of the discontinuous IP address number. The basic principle is: After increasing the offset, the modified IP address number segment constitutes a continuous IP. For the specific example, refer to the foregoing method embodiment, and details are not described herein again.

A person skilled in the art may understand that all or part of the various steps of the foregoing embodiments may be completed by a program instructing related hardware. The program may be stored in a computer readable storage medium, and the storage medium may include: Read Only Memory (ROM), Random Access Memory (RAM), disk or optical disk.

The above description of the IP address allocation method and the corresponding gateway provided by the embodiment of the present invention is only for helping to understand the method and core idea of the present invention. Meanwhile, for those skilled in the art, according to the present invention, The present invention is not limited by the scope of the present invention.

Claims

Rights request

A method for allocating an IP address, comprising:

Obtaining a unique identification code of the mobile terminal;

Mapping the mapping variable to the last three segments of the IP address by using a unique identification field or the unique identification code in the unique identification code as a mapping variable;

Reading the subnet number to which the unique identifier code belongs from the configuration information, and combining the prefix with the subnet number as the IP address and the last three segments of the IP address into an IP address;

Assigning the IP address obtained by the combination to the mobile terminal.

2. The IP address allocation method according to claim 1, wherein the mobile terminal unique identification code is an international mobile device identity code.

The IP address allocation method according to claim 1, wherein the unique identifier of the mobile terminal is an international mobile subscriber identity code, and the unique identifier field in the unique identifier code is a mobile subscriber authentication number MSIN.

The method for generating an IP address according to claim 3, wherein the mapping of the mapping variable to the last three segments of the IP address is performed by using the unique identifier field in the unique identifier code of the mobile terminal as a mapping variable, and the method includes:

Three mapping parameters are selected;

Performing three kinds of operation operations on the mapping factor by using one of the mobile user authentication number (MSIN) and one of the three mapping parameters as a mapping factor, and the three operation results are obtained. As the last three segments of the IP address.

The method for generating an IP address according to claim 4, wherein the mapping parameter is used as a mapping factor by using one of the mobile user authentication number MSIN and three mapping parameters, respectively. After performing three kinds of operations, three kinds of operation results are obtained:

Using 255 X 254 and 255 as the first mapping parameter, the operation result obtained after the (MSIN/255 x 254) %255 operation is performed as the first segment of the last three segments of the IP address; Using 254 and 255 as the second mapping parameter, the operation result obtained after the (MSIN/254) %255 operation operation is performed as the second segment of the last three segments of the IP address;

Using 254 as the third mapping parameter, the operation result obtained after the (MSIN%255) + 1 operation is performed as the third segment of the last three segments of the IP address;

The "X" is a multiplication operation, the "/" is a division operation, and the "%" is a modulo operation.

6. The IP address allocation method according to claim 1, wherein the mapping is a linear mapping.

The IP address allocation method according to claim 1, wherein if the unique identification code number segments formed by the unique identification code of the mobile terminal are discontinuous, the IP address obtained after the mapping is formed. The discontinuous IP address number segment is modified to become a continuous IP address number segment.

8. The IP address allocation method according to claim 7, wherein the correction method comprises:

Determining the reference IP address by using the endpoint of the IP address number segment as a reference IP address

A gateway, wherein the gateway comprises:

An obtaining module, configured to acquire a unique identification code of the mobile terminal;

a mapping module, configured to map the mapping variable to a last three segments of an IP address by using a unique identifier field in the mobile terminal unique identifier code or the unique identifier code as a mapping variable;

An IP address combination module, configured to read, from the configuration information, a subnet number to which the unique identifier is assigned, and combine the prefix with the subnet number as an IP address with the last three segments of the IP address to form an IP address;

And an allocating module, configured to allocate an IP address obtained by combining the IP address combination modules to the mobile terminal.

The gateway according to claim 9, wherein the mobile terminal unique identification code is an international mobile subscriber identity code, and the unique identifier field in the unique identity code is a mobile subscriber authentication number MSIN.

The gateway according to claim 10, wherein the mapping module comprises: a parameter selection unit, configured to select three mapping parameters;

An operation unit, configured to use one of the three mapping parameters selected by the mobile user authentication number MSIN and the parameter selection unit as a mapping factor, and perform three operation operations on the mapping factor Three kinds of operation results are obtained, and the three operation results are used as the last three segments of the IP address.

The gateway according to claim 9, wherein the gateway further comprises:

The IP address number segment ^ίι爹正 module is configured to: when the unique identification code number segment formed by the unique identification code of the mobile terminal is mapped to obtain a discontinuous IP address number segment, perform the discontinuous IP address number segment Correction makes it a continuous IP address number segment.

The gateway according to claim 12, wherein the IP address number segment correction module is further configured to:

And determining, by the IP address based on the endpoint of the IP address number segment, an offset of the reference IP address, wherein the offset is determined according to the modified IP address number segment to form a continuous IP address number segment.