CN101150753A

CN101150753A - A load adjustment method and base station controller

Info

Publication number: CN101150753A
Application number: CNA2007100311180A
Authority: CN
Inventors: 胡红山
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2007-10-29
Filing date: 2007-10-29
Publication date: 2008-03-26
Anticipated expiration: 2027-10-29
Also published as: CN101150753B

Abstract

The embodiment of the invention discloses a method for adjusting load, comprising following steps: according to a capability index, acquiring the user amount which is capable of serving by each MSC, the capability index is used for indicating the load carrying capacity of the MSC; according to acquired user amount, setting the corresponding relation of users and MSC. The embodiment of the invention also discloses a basic station controller. Through setting the capability index of MSC, the invention can acquire the corresponding relation of users and MSC according to defined capability index, makes the network maintainers adjust load allocation between MSC only through amending the capability index, simplifies the complexity of network maintenance, reduces workload of network maintenance.

Description

Load adjusting method and base station controller

Technical Field

The present invention relates to the field of mobile communications, and in particular, to a load adjustment method and a base station controller.

Background

In a conventional Mobile communication network, one Mobile Switching Center (MSC) may be connected to a plurality of Base Station Controllers (BSCs), but one BSC may only be connected to one MSC, that is, the BSC and the MSC are in a star networking manner, and fig. 1 is a schematic diagram of a connection relationship between the MSC and the BSC in the conventional Mobile communication network.

The star networking mode of the MSC and the BSC restricts the flexibility of networking. For example, when the MSC is unavailable due to failure or shutdown maintenance, all users in the radio range covered by the BSC under the MSC will be affected; in addition, under the above networking architecture, when an MSC node is added in the network, a BSC must be added or migrated to the MSC at the same time.

In a mobile communication network supporting interface flexibility between an access network and a core network, for example, in a network using an a-interface flexibility (a-Flex) technology, one BSC may be connected to a plurality of MSCs, and one MSC may be connected to a plurality of BSCs. When a certain MSC is unavailable due to a fault and the like, other MSCs can serve the users in the coverage area of the BSC hung under the faulty MSC.

The A-Flex network structure ensures that the load among a plurality of MSCs can be conveniently redistributed, avoids overloading of a single MSC and achieves the purpose of load balancing.

a-Flex networking is shown in fig. 2, where there is at least one MSC Pool (MSC Pool) in the network. At least one MSC and one BSC are included in an MSC pool, each BSC in the MSC pool is connected with all MSCs, and users covered by the BSC can select any MSC in the same pool to serve. Pool coverage (Pool-area) refers to the radio coverage of all BSCs in the MSC Pool.

In a Code Division Multiple Access (CDMA) system that uses an a-Flex technology for networking, to implement that the same BSC belongs to Multiple MSCs, the following method may be specifically used:

a. a mobile user initiates a service request to the BSC 1;

b. BSC1 finds out MSC capable of serving the mobile user as MSC1;

in this step, the BSC1 may search for an MSC serving the user from a set correspondence table between the user and the MSC, set a user identifier (such as an international mobile subscriber identity IMSI) and an MSC identifier in the table, and correspond the two identifiers to each other. The user identifier may also be obtained according to other predetermined policies, such as calculating according to the HASH algorithm: the BSC divides the users in the range covered by the MSC pool into M groups according to their user identities IMSI, each group is called a user block, and then the system uniformly corresponds these user blocks to the MSC, and the table thus obtained can be called "load sharing relationship table of user block and MSC", as shown in table 1 specifically.

TABLE 1

User block identification	MSC identification
User block identification	MSC identification	000	MSC0
001	MSC1	000	MSC0
001	MSC1	002	MSC2
... ...	... ...	002	MSC2
... ...	... ...	123	MSC1
... ...	... ...	123	MSC1
... ...	... ...	M-1	MSCi

Thus, the BSC1 can find the MSC corresponding to the mobile subscriber through the load sharing relationship table between the subscriber block and the MSC, thereby implementing that the BSC belongs to a plurality of MSCs.

c. BSC1 forwards the service request message of the mobile user to MSC1;

through the above process, the load balance on the MSC can be realized by maintaining the corresponding relation between the user and the MSC in the same pool.

Maintenance personnel can configure the corresponding relation between users and the MSC through an OAM (Operation Administration and Maintenance) interface, so that a certain user in the BSC coverage range in the pool is processed by a certain MSC in the same pool.

When the number of the user blocks is large and a plurality of MSCs exist in the pool, the corresponding relationship between the user blocks and each MSC is complex, and the work of directly configuring the corresponding relationship between the user (or user block) and the MSC to realize load balancing of the MSCs in the pool becomes very heavy.

Disclosure of Invention

The technical problem to be solved in the embodiments of the present invention is to provide a method for load adjustment and a base station controller, which can implement convenient adjustment of the load of an MSC in a network using an a-Flex technology.

In order to solve the above technical problem, in one aspect, an embodiment of the present invention provides a method for load adjustment, including the following steps: acquiring the user quantity which can be served by each MSC according to a capacity index, wherein the capacity index is used for indicating the load bearing capacity of the MSC; and setting the corresponding relation between the user and the MSC according to the acquired user quantity.

In another aspect, an embodiment of the present invention provides a base station controller, which includes: a first storage module for storing a capacity index of an MSC, the capacity index being indicative of a load carrying capacity of the MSC; the calculation module is used for calculating the user quantity which can be served by each MSC according to the MSC capacity index stored by the first storage module; the setting module is used for setting the corresponding relation between the user and the MSC according to the calculation result of the calculation module; and the second storage module is used for storing the corresponding relation between the user and the MSC set by the setting module.

The corresponding relation between the user and the MSC can be obtained through a certain algorithm according to the defined capacity index, so that the network maintainer can adjust the load distribution among the MSC only by modifying the capacity index, the complexity of network maintenance is simplified, and the workload of network maintenance is reduced.

Drawings

Fig. 1 is a schematic diagram of a conventional network structure that does not support interface activation between an access network and a core network;

FIG. 2 is a schematic diagram of a conventional network architecture supporting A-Flex technology;

FIG. 3 is a block diagram of an embodiment of a base station controller of the present invention;

FIG. 4 is a schematic diagram of another embodiment of a base station controller of the present invention;

FIG. 5 is a schematic diagram of another embodiment of a base station controller of the present invention;

FIG. 6 is a schematic diagram of the components of one embodiment of the first adjustment module of FIG. 5;

FIG. 7 is a flow diagram illustrating one embodiment of a method of load leveling in accordance with the present invention;

fig. 8 is a flow chart illustrating another exemplary embodiment of a method for load adjustment according to the present invention.

Detailed Description

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. In the referenced figures, like parts are designated with like reference numerals in the different figures.

Fig. 3 is a schematic diagram of a base station controller according to an embodiment of the present invention. As shown in the figure, a Base Station Controller (BSC) 1 includes: a first storage module 10, a calculation module 12, a setup module 14 and a second storage module 16.

The first storage module 10 is configured to store a capacity index of the MSC, where the capacity index is used to indicate a load carrying capacity of each MSC. The first storage module 10 may record the capacity index of the MSC in the form of an MSC capacity index table, where the table includes MSC identifiers and MSC capacity indexes, each MSC identifier corresponds to each MSC capacity index one by one, the ratio of the capacity indexes of the MSCs may reflect a proportional relationship of load bearing capacities of the MSCs, and allocating users according to the proportional relationship may realize load balancing among the MSCs. For example, table 2 shows a table of capacity indexes of MSCs configured on each BSC of the MSC Pool 1 in fig. 2.

TABLE 2

MSC identification	MSC Capacity index
MSC identification	MSC Capacity index	MSC0	2000
MSC1	1000	MSC0	2000
MSC1	1000	MSC2	1000

As shown in table 2, each MSC is identified as MSC0, MSC1, and MSC2, and the capacity index of each MSC is: when the capacity index of MSC0 is 2000, the capacity index of MSCs 1 is 1000, and the capacity index of MSCs 2 is 1000, and subscribers are allocated among MSC0, MSC1, and MSC2 according to the capacity index, if the subscriber amounts corresponding to the respective MSCs are in such a ratio that the subscriber amount of MSC0 to the subscriber amount of MSC1 to the subscriber amount of MSC2= 2000 to 1000, load balancing can be achieved among the respective MSCs. It should be noted that the specific numerical value of the table capacity index is not important, and the capacity index mainly represents the ratio of the load capacities of the corresponding MSCs.

The calculating module 12 obtains the user amount that each MSC can serve according to the capacity index of the MSC stored in the first storing module 10. The user amount that can be served specifically means that the user amount that each MSC can serve according to its capacity index is obtained according to the total user amount of all users in the coverage area of the same MSC pool, for example, if the MSC pool shares MSC1 and MSC2, the capacity indexes of the two are MSC 1: MSC2= 1000: 2000, and the users in the coverage area of the corresponding MSC pool share 9000, the user amount that MSC1 can serve is:

similarly, the number of users that can be served by the MSC2 is 6000.

The setting module 14 is configured to set a corresponding relationship between the user and the MSC according to the user amount obtained by the calculating module 12. Referring to the above example, 3000 users of 9000 users may correspond to MSC1, and 6000 users may correspond to MSC2 according to a certain rule, where the rule is related to a policy for identifying users, and if different users are represented by IMSI of the users, 3000 users of small numbers may correspond to MSC1, and 6000 users of large IMSI numbers may correspond to MSC2, or 3000 users may correspond to MSC1 randomly according to IMSI, and another 6000 users may correspond to MSC2 according to IMSI. Specifically, there may be other multiple options for the rule corresponding to a certain user and a certain MSC, and details are not repeated here.

The second storage module 16 is used for storing the corresponding relationship between the user and the MSC set by the setting module 14. Similarly, the second storage module 16 may record the correspondence between the user and the MSC in a correspondence table between the user and the MSC, where the user identifier and the MSC identifier corresponding to the user identifier are recorded in the table. If the IMSI is used as the subscriber identity, the number segment configuration table may be used as a correspondence table between the subscriber and the MSC to represent the correspondence between the subscriber and the MSC. Table 3 is a number segment configuration table obtained according to the MSC capacity index in table 2. According to table 2, it can be known that the capacity index of MSC0, the capacity index of MSC1, and the capacity index of MSC2= 2000: 1000, and then the users in the coverage area of MSC Pool 1 can be divided into 3 groups, and the specific user amount of each group is determined, and these user groups are respectively corresponded to each MSC, so as to obtain table 3.

TABLE 3

IMSI number segment	MSC identification
IMSI number segment	MSC identification	46003090000xxxx	MSC0
46003090003xxxx	MSC0	46003090000xxxx	MSC0
46003090003xxxx	MSC0	46003090004xxxx	MSC1
46003090001xxxx	MSC2	46003090004xxxx	MSC1

In table 3, the user corresponding to the MSC identified as MSC0 is a user whose IMSI is 460030900000001-460030900009999, and 460030900030001-460030900039999; the user corresponding to MSC1 is a user with IMSI of 460030900040001-460030900049999; the users corresponding to MSC2 are users with IMSIs of 460030900010001-460030900019999. It is assumed here that the IMSI of the subscriber in the MSC Pool 1 coverage is in the above number segment.

For the case of using the IMSI as the subscriber identity, the corresponding relationship table between the subscriber and the MSC may also be set in other manners, which is not illustrated here.

If the identifier obtained by the HASH algorithm is used as the user identifier, the corresponding relationship between the user and the MSC can be represented by using the corresponding relationship table between the user block and the MSC. Table 4 is a table of the corresponding relationship between the user block of MSC Pool 1 and the MSC in fig. 2. The identifier used by the "subscriber block" is a number from 0 to 999, obtained by modulo 1000 the IMSI number of the subscriber according to the HASH algorithm.

Table 4:

user block identification	MSC identification
user block identification	MSC identification	0-499	MSC0
500-749	MSC1	0-499	MSC0
500-749	MSC1	750-999	MSC2

In table 4, the user blocks with user block identifications 0 to 499 correspond to the MSC with identification MSC0, the user blocks with user block identifications 500 to 749 correspond to the MSC with identification MSC1, and the user blocks with user block identifications 750 to 999 correspond to the MSC with identification MSC2.

It should be noted that the user block with the specific identifier is not necessarily only capable of corresponding to the MSC with the specific identifier, and the number of users included in the user block corresponding to each MSC is only required to conform to the principle in the algorithm given above. The same is true in other specific embodiments described below.

Fig. 4 is a schematic diagram of another embodiment of a base station controller according to the present invention. As shown, the base station controller 2 has a configuration module 20 in addition to the first storage module 10, the calculation module 12, the setting module 14, and the second storage module 16 as described above. The configuration module 20 is configured to configure and store the capacity index of each MSC in the MSC pool in the storage module 10. Network maintenance personnel can adjust the load bearing condition of the MSC by using the configuration module to configure the capacity index table of the MSC in the network through the OAM interface.

Fig. 5 is a schematic diagram of a base station controller according to another embodiment of the present invention. As shown, the base station controller 3 includes a detection module 31, a first adjustment module 33, and a second adjustment module 35, in addition to the first storage module 10, the calculation module 12, the setting module 14, and the second storage module 16. Meanwhile, the base station controller 3 may also optionally include the configuration module 20.

When an MSC in the MSC pool fails (the failure may be a BSC-to-MSC link is not reachable or the MSC is damaged), the subscriber connected to the failed MSC needs to be adjusted.

The detecting module 31 is configured to perform fault detection on an MSC in the network, and when it detects that there is an MSC fault, the first adjusting module 33 adjusts the corresponding relationship between the user and the MSC stored in the second storing module 16.

Fig. 6 is a schematic diagram illustrating a first adjusting module in fig. 5 according to an embodiment. As shown in the figure, the first adjusting module 33 further includes: a chunking module 330 and an updating module 332. The blocking module 330 blocks the users corresponding to the failed MSC according to the capacity index ratio of the non-failed MSC; the updating module 332 establishes a corresponding relationship between the blocked subscriber block and the corresponding non-faulty MSC according to the blocking result of the blocking module 330, and updates the corresponding relationship between the subscriber and the MSC stored in the second storage module 16.

Referring to the capacity index of the MSC given in table 2 and the corresponding relationship between the user block and the MSC given in table 4, if the detecting module 31 detects that the MSC0 fails, the partitioning module 33 divides the user block corresponding to the failed MSC0 into two blocks, i.e., 0 to 254, 255 to 499, according to the capacity index ratio of non-failed MSCs (MSC 1 and MSC 2). The updating module 332 corresponds the user blocks identified as 0-254 to the MSC1, and the user blocks identified as 255-499 to the MSC2, and obtains an updated corresponding relationship table 5 between the user blocks and the MSC.

Table 5:

user block identification	MSC identification
user block identification	MSC identification	--	MSC0
0-254，500-749	MSC1	--	MSC0
0-254，500-749	MSC1	255-499，750-999	MSC2

In this example, since the capacity index of MSC1 is the same as the capacity index of MSC2, any one of two blocks 0 to 254 and 255 to 499 may correspond to MSC1, and the other block corresponds to MSC2.

When the detecting module 31 detects that the failure of the MSC is recovered, the second adjusting module 35 adjusts the corresponding relationship between the user and the MSC stored in the second storing module 16 according to the MSC capacity index stored in the first storing module 10. The specific adjustment process is similar to the corresponding relationship process of the calculation module 12 and the setting module 14 for setting the user and the MSC, and is not described herein again. For the cases given in table 2 and table 5, if the MSC0 fails to recover, the second adjusting module 35 may retrieve the corresponding relationship between the subscriber block and the MSC as given in table 4 according to table 2.

A method for load adjustment provided in an embodiment of the present invention is described in detail below. Fig. 7 is a schematic flowchart of a method for load adjustment according to an embodiment of the present invention. The load adjustment method comprises the following steps:

step S701, obtaining the user quantity which can be served by each MSC according to a capacity index, wherein the capacity index is used for indicating the load bearing capacity of the MSC. That is, the users within the coverage area of the corresponding MSC pool are divided into the same number of user blocks as the total number of MSCs in the pool according to the capacity index ratio of each MSC in the MSC pool, and the ratio of the number of users of each user block is consistent with the ratio of the capacity index of each MSC, so that the number of users that each MSC can serve is the number of users of the corresponding user block.

Step S702, setting the corresponding relation between the user and the MSC according to the obtained user quantity.

Thus, when BSC receives the message sent by user, it forwards the message to corresponding MSC according to the corresponding relation between user and MSC, or BSC sends the data from MSC to corresponding user

Fig. 8 is a schematic flow chart of another embodiment of a method for load adjustment according to the present invention.

Step S801, configure a capacity index for each MSC in the network.

Step S802, obtaining the user quantity which can be served by each MSC according to the capacity index.

Step S803, setting the corresponding relation between the user and the MSC according to the obtained user quantity.

Step S801 is added to fig. 8 compared to the steps in fig. 7. Therefore, when a new MSC needs to be added into the network or the load capacity of the original MSC in the network needs to be changed, the maintenance personnel can automatically realize the correspondence between the user and the MSC by reconfiguring the capacity index of the MSC stored in the BSC in the same MSC pool through OAM. For example, when a certain MSC is found to be relatively busy during operation, part or all of the users originally carried by the MSC can be automatically adjusted to other MSC(s) by reducing the capacity index of the MSC; when a certain MSC is found to be relatively idle, part or all of users carried by other MSCs can be automatically adjusted to the MSC for carrying by increasing the capacity index of the MSC; when a new MSC needs to be added to the network, as long as the capacity index is set for the new MSC, part or all of users borne by other MSCs in the network can be automatically adjusted to the newly added MSC for bearing; similarly, the operation when the MSC in the network needs to be reduced is also similar and will not be described one by one here.

In particular, the network described in the method may be a pool of MSCs defined in the a-Flex framework.

The above-mentioned MSC capacity index and the corresponding relationship between the user and the MSC can be described by using corresponding tables. For example, an MSC capacity index table may be provided, in which the MSC identifications and the MSC capacity indexes are recorded respectively, and each MSC identification corresponds to each MSC capacity index one by one, and specifically, refer to table 2 described in the above embodiment.

The correspondence between the user and the MSC described in step S702 and step S803 may be represented by a correspondence table between the user and the MSC. The relation table includes a user identifier and an MSC identifier corresponding to the user identifier, and a specific object of the user identifier may be an International Mobile Subscriber Identity (IMSI), an identifier obtained by a HASH algorithm, or an identifier specified by an operator according to different user identifier obtaining policies.

If the IMSI is used as the subscriber identity, the number segment configuration table may be used as a corresponding relationship table between the subscriber and the MSC to represent the corresponding relationship between the subscriber and the MSC, which may specifically refer to table 3 described in the above embodiment. If the identifier obtained by the HASH algorithm is used as the user identifier, the corresponding relationship between the user and the MSC may be represented by using the corresponding relationship table between the user block and the MSC, and specifically, reference may be made to table 4 described in the foregoing embodiment.

When the failure of the MSC in the network is detected, the following steps are executed:

step S901, partitioning the users corresponding to the failed MSC according to the capacity index ratio of the non-failed MSC, and establishing a corresponding relation between the partitioned user blocks and the corresponding non-failed MSC;

step S902, updating the corresponding relation between the users and the MSC in the network.

When the failure recovery of the MSC in the network is detected, the corresponding relation between the users and the MSC in the network is updated again according to the MSC capacity index.

To further understand the above process, the following is exemplified:

assuming that the MSC pool has four MSCs, MSC0, MSC1, MSC2, and MSC3, the MSC capacity index of the MSC pool when these MSCs are all normally served is set as in table 6:

table 6:

MSC identification	Index of capacity
MSC identification	Index of capacity	MSC1	1000
MSC2	1500	MSC1	1000
MSC2	1500	MSC3	1500
MSC4	1000	MSC3	1500

According to step S702, it can be known that the capacity index ratio of MSC in table 6 is MSC 0: MSC 1: MSC 2: MSC4= 1000: 1500: 1000, and a HASH algorithm is used for the user to obtain a user block with a user identifier of 0-999. The user block is divided into 4 user blocks according to the capacity index of MSC (the table has 4 MSC in total), and the user quantity in each user block is 200: 300: 200, therefore, the user can be divided into four blocks according to the user block identification: 0 to 199, 200 to 499, 500 to 799, and 800 to 999 (when users are blocked by user amounts, the user blocks may not be divided in this order, and the ratio between the user blocks may be in accordance with the ratio of the user amounts in the user blocks), and a table of correspondence between the user blocks and the MSCs is obtained as shown in table 7. When all the MSCs are in normal service, the corresponding relation between the user and the MSC is established according to the table 7.

Table 7:

user block identification	MSC identification
user block identification	MSC identification	0-199	MSC0
200-499	MSC1	0-199	MSC0

500-799	MSC2
500-799	MSC2	800-999	MSC3

If the MSC3 failure or the link to the MSC3 failure is detected, step S901 and step S902 are executed, and according to this step, the MSC capacity index table shown in table 6 is not changed, and table 7 is adjusted to obtain the corresponding relationship table between the user block and the MSC shown in table 8. And then reestablishes the corresponding relationship between the user and the MSC according to the table 8.

Table 8:

user block identification	MSC identification
user block identification	MSC identification	0-199，800-849	MSC0
200-499，850-924	MSC1	0-199，800-849	MSC0
200-499，850-924	MSC1	500-799，924-999	MSC2
--	MSC3	500-799，924-999	MSC2

In this embodiment, the failed MSC is MSC3, the corresponding subscriber is a subscriber with a subscriber block identifier of 800-999, and the non-failed MSCs are MSC0, MSC1, and MSC2. When detecting that MSC3 has a fault, the capacity index between non-fault MSCs is MSC 0: MSC 1: MSC2= 1: 1.5; the user blocks 800-999 are divided into three parts according to the proportion, namely 800-849, 850-924 and 924-999, and then the three parts are respectively corresponding to non-fault MSCs (MSC 0, MSC1 and MSC 2), and the original corresponding user blocks of the MSC0, the MSC1 and the MSC2 are not changed, so that the corresponding relation between the users and the MSCs shown in the table 8 is obtained. When the user blocks 800 to 999 are divided into three parts according to the corresponding proportion, the specific division strategy can be different from the sequential division method in the present example as long as the proportion between the three parts meets the corresponding requirement. Meanwhile, when the three parts are corresponding to the MSC0, the MSC1 and the MSC2, the user block with the specific identifier is not necessarily only corresponding to the MSC with the specific identifier, and the number of users included in the user block corresponding to each MSC is only in accordance with the principle in the given algorithm. In this example, the user blocks with user block identifiers 800-849 can only correspond to MSC 0; however, since the capacity indexes of MSC1 and MSC2 are the same, 850 to 924 can correspond to MSC1 or MSC2, and 924 to 999 can correspond to one of the MSCs, and the other MSC.

When the MSC3 failure recovers (it may be that the MSC3 is repaired or the link failure to the MSC3 is recovered), table 7 may be obtained again according to table 6, and the corresponding relationship between the user and the MSC is established according to table 7.

If a plurality of MSC faults exist in the network, all users related to the fault MSC are distributed according to the algorithm.

By setting the capacity index of the MSC and defining the process of obtaining the corresponding relation between the user and the MSC by using the capacity index, the network maintenance party can automatically realize load balance distribution among the MSCs only by modifying the capacity index, thereby simplifying the complexity of network maintenance and simultaneously reducing the workload of network maintenance.

Meanwhile, when the MSC in the MSC pool has a fault, the corresponding relation between the new user and the MSC can be obtained only by adjusting the algorithm according to the corresponding relation between the user and the MSC, the MSC capacity index is not required to be modified, the user related to the fault MSC is not required to be operated by a network maintenance party, and the system can automatically and properly distribute the user related to the fault MSC. The workload of network maintenance is reduced.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method of load adjustment comprising the steps of:

acquiring the user quantity which can be served by each MSC according to a capacity index, wherein the capacity index is used for indicating the load bearing capacity of the MSC;

and setting the corresponding relation between the user and the MSC according to the acquired user quantity.

2. The method of claim 1 wherein the capacity index is configured for each MSC in the network prior to said obtaining the number of subscribers that each MSC can serve based on the capacity index.

3. The method of claim 1, wherein the MSC capacity index is recorded by an MSC capacity index table, the capacity index table comprising MSC identifications and MSC capacity indexes, each MSC identification corresponding to each MSC capacity index.

4. The method according to claim 1, wherein the correspondence between the subscriber and the MSC is recorded by a correspondence table between the subscriber and the MSC, the correspondence table between the subscriber and the MSC includes a subscriber identifier and an MSC identifier, and each subscriber identifier corresponds to each MSC identifier one to one.

5. The method according to any of claims 1 to 4, characterized in that when a failure of an MSC in the network is detected, the steps of:

and updating the corresponding relation between the user and the MSC in the network according to the corresponding relation adjustment algorithm between the user and the MSC.

6. The method of claim 5, wherein when a failure recovery of an MSC in the network is detected, the corresponding relationship of users and MSCs in the network is re-updated according to the MSC capacity index.

7. The method of claim 5, wherein the step of updating the correspondence between the subscribers and the MSCs in the network based on the subscriber-to-MSC correspondence adjustment algorithm further comprises:

and partitioning the users corresponding to the failed MSC according to the capacity index proportion of the non-failed MSC, establishing a corresponding relation between each non-failed MSC, and updating the corresponding relation between the users and the MSC in the network.

8. The method of claim 7, wherein the network is a pool of MSCs in an a-Flex architecture.

9. A base station controller comprising:

a first storage module, configured to store a capacity index of an MSC, where the capacity index is used to indicate a load carrying capacity of the MSC;

the calculation module is used for calculating the user quantity which can be served by each MSC according to the MSC capacity index stored by the first storage module;

the setting module is used for setting the corresponding relation between the user and the MSC according to the calculation result of the calculation module;

and the second storage module is used for storing the corresponding relation between the user and the MSC set by the setting module.

10. The base station controller of claim 9, wherein the base station controller further comprises:

and the configuration module is used for configuring the capacity index of each MSC in the network and storing the capacity index in the first storage module.

11. The base station controller according to claim 9 or 10, wherein the base station controller further comprises:

the detection module is used for carrying out fault detection on the MSC in the network;

and the first adjusting module is used for adjusting the corresponding relation between the user and the MSC stored in the second storage module when the detecting module detects that the MSC has a fault.

12. The base station controller of claim 11, wherein the first adjusting module further comprises:

the blocking module is used for blocking the users corresponding to the failed MSC according to the capacity index of the non-failed MSC;

and the updating module is used for establishing a corresponding relation between the user block blocked by the blocking module and the corresponding non-failure MSC and updating the corresponding relation between the user and the MSC stored by the second storage module.

13. The base station controller of claim 11, wherein the base station controller further comprises:

and the second adjusting module is used for adjusting the corresponding relation between the users and the MSC stored in the second storage module according to the MSC capacity index stored in the first storage module when the detection module detects that the fault of the MSC is recovered.