CN102918880B - The access control method of node B cache, Apparatus and system - Google Patents

Abstract

The access control method of a kind of node B cache of disclosure, Apparatus and system, relate to communication technical field, improves the hit rate of base station Cache. Including: source base station receives the request message carrying content identification that terminal sends; When described source base station buffer memory is absent from the content mated with described content identification, search the target BS depositing the content mated with described content identification; The request message carrying described content identification is sent to described target BS. The embodiment of the present invention is mainly used in node B cache to carry out in the process of access to content.

Description

Base station cache access control method, device and system

technical field

The present invention relates to the field of communication technology, in particular to a base station buffer access control method, device and system.

Background technique

At present, the application of Cache (network information cache) technology on the base station can cache the content of the remote server that the user terminal needs to access in the Cache of the base station, so as to improve the access speed of the user and reduce the network bandwidth. For example, the Cache technology can be directly applied to the eNodeb (evolved base station) under the fourth-generation wireless communication systems such as LTE (Long Term Evolution, Long Term Evolution), WIMAX (Worldwide Interoperability for Microwave Access, etc.); or, in UMTS (Universal Mobile Telecommunications System, Universal mobile communication system), TDS-CDMA (TimeDivisionSynchronous-CDMA, time division synchronous CDMA), CDMA (CodeDivisionMultipleAccess, code division multiple access) and other flat base stations under third-generation wireless communication systems or base stations that implement GiOffload (Gi interface offloading) Application of Cache technology.

In the prior art, taking the UMTS standard in the third-generation wireless communication system as an example, the above-mentioned base station applying the Cache technology provides the content caching service for users as follows: Assume that the current base station of the service terminal is base station A, then, if the terminal needs If the accessed content is not matched in the Cache of base station A, it will continue to obtain the accessed content from the content server on the Internet through GiOffload; Obtain access content; if the content that the terminal needs to access belongs to the non-offload business type, then through the original path of the wireless access network, the RNC (RadioNetworkController, radio network controller)/xGSN accesses the content server of the Internet, and after obtaining the access content , and then the RNC pushes the content to the Cache of base station A; or accesses the RNC Cache or xGSN cache through the original path of the wireless access network to obtain the access content, and after obtaining the access content, the RNC pushes the content to the base station A on the Cache.

However, when a Cache is deployed on an existing base station, the number of users served by a single base station is usually relatively small, and the dispersion of accessing the base station is high, so that the Cache hit rate of the base station is low. In order to ensure the hit rate of the Cache of the base station, a large-capacity memory needs to be configured for the Cache of each base station, thereby increasing the hardware cost of the base station.

Contents of the invention

Embodiments of the present invention provide a base station cache access control method, device and system, which improve the hit rate of the base station Cache.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

On the one hand, an access control method for base station cache is provided, including:

The source base station receives the request message carrying the content identifier sent by the terminal;

When there is no content matching the content identifier in the cache of the source base station, search for a target base station storing the content matching the content identifier;

Sending a request message carrying the content identifier to the target base station.

In one aspect, a communication device is provided, including:

a receiving unit, configured to receive a request message carrying a content identifier sent by the terminal;

A search unit, configured to search for a target base station storing content matching the content identifier when there is no content matching the content identifier in the cache of the communication device;

A sending unit, configured to send a request message carrying the content identifier to the target base station.

In another aspect, a distributed base station caching system is provided, including: at least two base stations, where caching is provided on the base stations;

The base station is configured to receive a request message carrying a content identifier sent by a terminal; when there is no content matching the content identifier in the cache of the base station, search for a target base station storing content matching the content identifier; Sending a request message carrying the content identifier to the target base station.

In the embodiment of the present invention, the caches of multiple base stations are shared. After the source base station receives the content identifier sent by the terminal, if there is no content matching the content identifier in the cache of the source base station, it will search and store the content that matches the content identifier. The content identifies a target base station of the matched content, and sends a request message carrying the content ID to the target base station, so as to acquire the content matching the content ID from the target base station. That is, when the terminal does not obtain the content in the cache of one base station, it can also obtain the content from the cache of other base stations. Compared with the prior art, the number of users served by a single base station is relatively small, resulting in a relatively low cache hit rate of the base station. Compared with the lower one, the embodiment of the present invention improves the hit rate of the cache of the base station, and does not need to upgrade the cache of the base station to a larger capacity, thereby reducing the hardware requirements for deploying the cache on the base station.

Description of drawings

FIG. 1 is a flowchart of an access control method for base station cache provided by an embodiment of the present invention;

FIG. 2 is a flow chart of another base station cache access control method provided by an embodiment of the present invention;

FIG. 3 is a flow chart of another access control method for base station cache provided by an embodiment of the present invention;

FIG. 4 is a flow chart of another base station buffer access control method provided by an embodiment of the present invention;

FIG. 5 is a first structural diagram of a communication device provided by an embodiment of the present invention;

FIG. 6 is a second structural diagram of a communication device provided by an embodiment of the present invention;

FIG. 7 is a first structural diagram of another communication device provided by an embodiment of the present invention;

FIG. 8 is a second structural diagram of another communication device provided by an embodiment of the present invention;

FIG. 9 is a structural diagram of a base station system provided by an embodiment of the present invention;

FIG. 10 is a structural diagram of another base station system provided by an embodiment of the present invention.

detailed description

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.

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, an embodiment of the present invention provides a method for access control of base station cache, the method is executed by the source base station, including:

101. The source base station receives the request message carrying the content identifier sent by the terminal;

The source base station is the current base station of the serving terminal.

102. When there is no content matching the content identifier in the cache of the source base station, search for a target base station storing the content matching the content identifier;

The target base station is: a base station that can communicate with the source base station.

For example, both the source base station and the target base station are base stations that adopt a Mesh (wireless mesh) networking manner within a certain area. Any two base stations using the Mesh (wireless grid) networking method can maintain wireless interconnection.

103. Send a request message carrying the content identifier to the target base station.

After receiving the request message carrying the content identifier, the target base station obtains the content matching the content identifier and sends it to the source base station, and the source base station sends the content to the terminal.

In the application scenario provided by the embodiment of the present invention: when the hit rate of the Cache (cache) of the defined base station reaches 50%, the capacity of the memory is required to be 3 TB. Assuming that all 100 base stations need to provide the Cache service with the same hit rate, when using the existing technology, a total of 300 TB of memory needs to be deployed in the 100 base stations. However, after adopting the method provided by the embodiment of the present invention, 3 TB of memory can be distributed in 100 base stations, that is, a total of 3 TB of memory needs to be deployed in 100 base stations. Therefore, the hardware investment for deploying the cache on the base station is effectively reduced, and the terminal can access the content on any one of the above 100 base station caches, that is, the terminal can share the content of the above 100 base station caches, thereby achieving and deploying a 300TB memory Same effect and hit rate.

It can be seen that in the embodiment of the present invention, after the source base station receives the content identifier sent by the terminal, if there is no content matching the content identifier in the cache of the source base station, it will search for the stored content that matches the content identifier. the target base station of the matched content, and send a request message carrying the content identifier to the target base station, so as to acquire the content matching the content identifier from the target base station. That is, when the terminal does not acquire content in the cache of one base station, it can also acquire content from the caches of other base stations, and the caches of multiple base stations are shared. Compared with the prior art, where the number of users served by a single base station is relatively small, resulting in a low cache hit rate of the base station, the embodiment of the present invention improves the cache hit rate of the base station, and at the same time, does not need to upgrade the cache of the base station to a larger Capacity, which in turn reduces the hardware requirements for deploying caches on base stations.

Further, the source base station and the target base station may both store a content index table, and the content index table includes identifiers and any content stored in the source base station cache and the target base station cache. A base station identifier corresponding to a content identifier.

At this time, in the above step 102, when there is no content matching the content identifier in the cache of the source base station, searching for the target base station that stores the content matching the content identifier may specifically be implemented as follows: When there is no content matching the content identifier in the cache of the source base station, look up the target base station identifier corresponding to the content identifier in the content index table.

Specifically, in the above step 102, when there is no content matching the content identifier in the cache of the source base station, if at least two base station identifiers corresponding to the content identifier are found in the content index table, then Selecting one base station identifier from the at least two base station identifiers corresponding to the content identifier as the target base station identifier.

Further, in order to ensure the consistency of the content index tables saved on the source base station and the target base station, if the content in the cache of the base station changes, the content index tables need to be synchronized between the source base station and the target base station. In particular, as shown in FIG. 2, the above method may also include at least one of steps 104 and 105:

104. When the existing content is deleted from the cache of the source base station, delete the identifier of the existing content in the content index table saved by the source base station, and send the changed content index table to the target base station, so as to instruct the target base station to store the The content index table stored on the target base station is synchronously changed to the changed content index table.

105. When new content is added to the cache of the source base station, add a new content identifier to the content index table saved by the source base station, and send the changed content index table to the target base station, so as to instruct the target base station to store the target base station The content index table saved on the website is synchronously changed to the changed content index table.

In addition, in the embodiment of the present invention, if the content that the terminal needs to access is matched in the Cache of the source base station, the access content is directly obtained from the Cache of the source base station;

If the content that the terminal needs to access is not matched in the Cache of the source base station, and the source base station does not find the target base station that stores the content that matches the content identifier, it can also continue to the content server on the Internet through GiOffload access to content;

If the content that the terminal needs to access belongs to the non-offload service type, the RNC (Radio Network Controller, radio network controller)/xGSN can access the Internet content server through the original path of the wireless access network, and after obtaining the access content, the The RNC pushes the content to the Cache of base station A; or, if the content to be accessed by the terminal belongs to the non-offload service type, it can also access the Cache of the RNC or the cache of the xGSN through the original path of the wireless access network to obtain the access content. After obtaining the access content, the RNC pushes the content to the Cache of base station A.

As shown in FIG. 3, an embodiment of the present invention provides a base station cache access control method, which is specifically executed by the target base station, including:

301. The target base station receives a request message carrying a content identifier sent by a source base station.

302. Acquire content matching the content identifier from the cache of the target base station.

303. Send the acquired content that matches the content identifier to the source base station, so that the source base station sends the content to the terminal.

In the embodiment of the present invention, the target base station receives the request message carrying the content identifier sent by the source base station, obtains the content matching the content identifier, and sends it to the source base station. That is, when the terminal does not acquire content in the cache of the source base station, it can also acquire content from the cache of other base stations (such as the target base station), and the caches of multiple base stations are shared. Compared with the prior art, where the number of users served by a single base station is relatively small, resulting in a low cache hit rate of the base station, the embodiment of the present invention improves the cache hit rate of the base station, and at the same time, does not need to upgrade the cache of the base station to a larger Capacity, which in turn reduces the hardware requirements for deploying caches on base stations.

Further, both the source base station and the target base station store a content index table, and the content index table includes identifiers of all contents stored in the cache of the source base station and the cache of the target base station and any content Identifies the corresponding base station identifier.

Further, optionally, as shown in FIG. 4, the method further includes at least one of steps 304 and 305:

304. The target base station receives the changed content index table sent by the source base station, where the changed content index table is obtained by the source base station after deleting the existing content identifier in the content index table saved by the source base station; and The content index table stored on the target base station is synchronously changed to the changed content index table. Therefore, the content index table stored on the source base station is consistent with the content index table stored on the target base station.

305. The target base station receives the changed content index table sent by the source base station, the changed content index table is obtained by the source base station after adding a new content identifier to the content index table saved by the source base station; The content index table stored on the target base station is synchronously changed to the changed content index table. Therefore, the content index table stored on the source base station is consistent with the content index table stored on the target base station.

As shown in FIG. 5 , an embodiment of the present invention provides a communication device. The communication device is specifically a source base station, and includes: a receiving unit 11 , a searching unit 12 and a sending unit 13 .

Wherein, the receiving unit 11 is configured to receive the request message carrying the content identifier sent by the terminal;

A search unit 12, configured to search for a target base station storing content matching the content identifier when there is no content matching the content identifier in the cache of the communication device;

The sending unit 13 is configured to send a request message carrying the content identifier to the target base station.

In this embodiment, the current base station of the serving terminal is referred to as the source base station. After the source base station receives the content identifier sent by the terminal, if there is no content matching the content identifier in the cache of the source base station, it will search for the stored content. A target base station of the content matching the content identifier, and sending a request message carrying the content identifier to the target base station, so as to acquire the content matching the content identifier from the target base station. That is, when the terminal does not acquire content in the cache of one base station, it can also acquire content from the caches of other base stations, and the caches of multiple base stations are shared. Compared with the prior art, where the number of users served by a single base station is relatively small, resulting in a low cache hit rate of the base station, the embodiment of the present invention improves the cache hit rate of the base station, and at the same time, does not need to upgrade the cache of the base station to a larger Capacity, which in turn reduces the hardware requirements for deploying caches on base stations.

Further, the communication device and the target base station both store a content index table, and the content index table includes all content identifiers and any content stored in the buffer memory of the communication device and the target base station Identifies the corresponding base station identifier.

The search unit 12 is specifically configured to search a content index table for a target base station identifier corresponding to the content identifier when there is no content matching the content identifier in the cache of the communication device.

Further, the search unit 12 is specifically configured to find at least two base station identifiers corresponding to the content identifier in the content index table when there is no content matching the content identifier in the cache of the communication device. , selecting a base station identifier from the at least two base station identifiers corresponding to the content identifier as the target base station identifier.

Further, in order to ensure the consistency of the content index tables saved on the source base station and the target base station, if the content in the cache of the base station changes, the content index tables need to be synchronized between the source base station and the target base station. As shown in FIG. 6 , the communication device above may further include: at least one of a first synchronization unit 14 and a second synchronization unit 15 .

The first synchronization unit 14 is configured to delete the existing content identifier in the content index table saved by the source base station when the existing content is deleted from the cache of the communication device, and send the changed content index table to The target base station is configured to instruct the target base station to synchronously change the content index table stored on the target base station into the changed content index table;

The second synchronization unit 15 is configured to add a new content identifier to the content index table saved by the source base station when new content is added to the cache of the communication device, and send the changed content index table to the target base station , to instruct the target base station to synchronously change the content index table saved on the target base station to the changed content index table.

As shown in FIG. 7 , an embodiment of the present invention provides another communication device. The communication device is specifically a target base station, and includes: a receiving unit 21 , an acquiring unit 22 and a sending unit 23 .

Wherein, the receiving unit 21 is configured to receive the request message carrying the content identifier sent by the source base station;

An acquisition unit 22, configured to acquire content matching the content identifier in the cache of the target base station;

The sending unit 23 is configured to send the acquired content matching the content identifier to the source base station.

In the embodiment of the present invention, the target base station receives the request message carrying the content identifier sent by the source base station, obtains the content matching the content identifier, and sends it to the source base station. That is, when the terminal does not acquire content in the cache of the source base station, it can also acquire content from the cache of other base stations (such as the target base station), and the caches of multiple base stations are shared. Compared with the prior art, where the number of users served by a single base station is relatively small, resulting in a low cache hit rate of the base station, the embodiment of the present invention improves the cache hit rate of the base station, and at the same time, does not need to upgrade the cache of the base station to a larger Capacity, which in turn reduces the hardware requirements for deploying caches on base stations.

Further, the communication device and the source base station both store a content index table, and the content index table includes all content identifiers and any content stored in the buffer memory of the communication device and the target base station Identifies the corresponding base station identifier.

Further, in order to ensure the consistency of the content index tables saved on the source base station and the target base station, if the content in the cache of the base station changes, the content index tables need to be synchronized between the source base station and the target base station. As shown in FIG. 8 , the communication device above may further include: at least one of a first synchronization unit 24 and a second synchronization unit 25 .

The first synchronization unit 24 is configured to delete the existing content identifier in the content index table saved by the source base station when the existing content is deleted from the cache of the communication device, and send the changed content index table to the target base station, to instruct the target base station to synchronously change the content index table stored on the target base station into the changed content index table

The second synchronization unit 25 is configured to add a new content identifier to the content index table saved by the source base station when new content is added to the cache of the source base station, and send the changed content index table to the the target base station, to instruct the target base station to synchronously change the content index table stored on the target base station into the changed content index table

As shown in FIG. 9 , the embodiment of the present invention also provides a base station system, including: a source base station 32 and a target base station 33, and caches are set on the source base station 32 and the target base station 33;

The source base station 32 is configured to receive a request message carrying a content identifier sent by a terminal; when there is no content matching the content identifier in the cache of the source base station, search for stored content matching the content identifier a target base station; sending a request message carrying the content identifier to the target base station, so as to acquire content matching the content identifier from the target base station, and send the content to the terminal;

The target base station 33 is configured to receive the request message carrying the content identifier sent by the source base station, acquire the content matching the content identifier in the cache of the target base station, and store the acquired content sent to the source base station.

As shown in FIG. 10, each base station may become a source base station 32 or a target base station 33. For example, when base station 3 in FIG. 10 is a source base station 32 and base station 2 is a target base station 33, if base station 3 receives A request message carrying a content identifier; when there is no content matching the content identifier in the cache of the base station 3, search for a target base station 33 (base station 2 in FIG. 10 ) that stores content matching the content identifier ; then the base station 3 sends a request message carrying the content identifier to the base station 2, and the base station 3 obtains the content matched by the content identifier from the cache of the base station 3 according to the request message carrying the content identifier, and sends to the base station 3, and then forwarded to the terminal 31 by the base station 3.

It can be seen that after the base station receives the content identifier sent by the terminal, if there is no content matching the content identifier in the base station cache, it will search for a target base station that stores the content matching the content identifier, and Sending a request message carrying the content identifier to the target base station, so as to acquire content matching the content identifier from the target base station. That is, when the terminal does not acquire content in the cache of one base station, it can also acquire content from the caches of other base stations, and the caches of multiple base stations are shared. Compared with the prior art, where the number of users served by a single base station is relatively small, resulting in a low cache hit rate of the base station, the embodiment of the present invention improves the cache hit rate of the base station, and at the same time, does not need to upgrade the cache of the base station to a larger Capacity, which in turn reduces the hardware requirements for deploying caches on base stations.

Further, both the source base station 32 and the target base station 33 store a content index table, and the content index table includes identifiers of all contents stored in each base station cache and a base station identifier corresponding to any content identifier .

Specifically, the base stations in a certain area using the Mesh networking form a base station system.

Further, the source base station 32 is specifically configured to search a content index table for a target base station identifier corresponding to the content identifier when there is no content matching the content identifier in the cache of the source base station.

Further, the source base station 32 is specifically configured to delete the existing content identifier in the content index table saved by the source base station when the existing content is deleted from the cache of the source base station, and index the changed content sending the table to the target base station to instruct the target base station to synchronously change the content index table saved on the target base station to the changed content index table;

The target base station 33 is specifically configured to receive the changed content index table sent by the source base station, and the changed content index table is after the source base station deletes the existing content identifier in the content index table saved by the source base station. Obtaining; and synchronously changing the content index table saved on the target base station to the changed content index table.

Further, the source base station 32 is specifically configured to add a new content identifier to the content index table stored in the source base station when new content is added to the cache of the source base station, and send the changed content index table to to the target base station to instruct the target base station to synchronously change the content index table stored on the target base station into the changed content index table;

The target base station 33 is specifically configured to receive the changed content index table sent by the source base station, and the changed content index table is obtained by adding a new content identifier to the content index table saved by the source base station by the source base station ; and synchronously changing the content index table saved on the target base station to the changed content index table.

In addition, the base station provided by the embodiment of the present invention can be an eNodeb (evolved base station) under the fourth-generation wireless communication system such as LTE and WIMAX, or it can be an eNodeb (evolved base station) under the third-generation wireless communication system such as UMTS, TD-SCDMA, and CDMA. Flattened base stations or base stations that implement GiOffload.

The embodiment of the present invention is mainly applied to the processing of content access on the base station cache, which can improve the hit rate of the base station Cache and reduce the hardware requirements for deploying the Cache on the base station.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (25)

1. An access control method for base station cache, characterized in that, comprising: The source base station receives the request message carrying the content identifier sent by the terminal; When there is no content matching the content identifier in the cache of the source base station, search for a target base station storing the content matching the content identifier; Sending a request message carrying the content identifier to the target base station, so as to acquire content matching the content identifier from the target base station, and send the content to the terminal; wherein, the target base station is: a base station that communicates with the source base station. 2. The access control method of base station cache according to claim 1, characterized in that, both the source base station and the target base station have a content index table, and the content index table includes information stored in the source base station All content identifiers in the cache and the target base station cache and the base station identifier corresponding to any content identifier. 3. The access control method of the base station cache according to claim 2, characterized in that, when there is no content matching the content identifier in the source base station cache, searching for stored content matching the content identifier The content of the target base station includes: When there is no content matching the content identifier in the cache of the source base station, look up a target base station identifier corresponding to the content identifier in a content index table. 4. The access control method for base station cache according to claim 3, wherein when there is no content matching the content identifier in the source base station cache, search a content index table for the content matching the content identifier. The target base station identifier corresponding to the content identifier includes: When there is no content matching the content identifier in the cache of the source base station, and at least two base station identifiers corresponding to the content identifier are found in the content index table, from the at least two base station identifiers corresponding to the content identifier, One of the base station identifiers corresponding to the content identifier is selected as the target base station identifier. 5. The access control method for base station cache according to claim 2, further comprising: When the existing content is deleted from the cache of the source base station, the existing content identifier is deleted from the content index table saved by the source base station, and the changed content index table is sent to the target base station to indicate the The target base station synchronously changes the content index table saved on the target base station to the changed content index table. 6. The access control method for base station cache according to claim 2, further comprising: When new content is added to the cache of the source base station, a new content identifier is added to the content index table saved by the source base station, and the changed content index table is sent to the target base station to indicate the target The base station synchronously changes the content index table saved on the target base station to the changed content index table. 7. An access control method for base station cache, characterized in that, comprising: The target base station receives the request message carrying the content identifier sent by the source base station; Obtain the content matching the content identifier in the cache of the target base station; Sending the obtained content that matches the content identifier to the source base station, so that the source base station can send the content to the terminal; wherein, the source base station is: interacting with the target base station base station for communication. 8. The access control method of the base station cache according to claim 7, characterized in that, both the source base station and the target base station have a content index table, and the content index table includes information stored in the source base station cache and the target base station. All content identifiers in the cache of the target base station and a base station identifier corresponding to any content identifier. 9. The access control method for base station cache according to claim 8, further comprising: The target base station receives the changed content index table sent by the source base station, and the changed content index table is obtained by the source base station after deleting the existing content identifier in the content index table saved by the source base station; Synchronously change the content index table saved on the target base station to the changed content index table. 10. The access control method for base station cache according to claim 8, further comprising: The target base station receives the changed content index table sent by the source base station, and the changed content index table is obtained by the source base station after adding a new content identifier to the content index table saved by the source base station; Synchronously change the content index table saved on the target base station to the changed content index table. 11. A communication device, characterized in that it comprises: a receiving unit, configured to receive a request message carrying a content identifier sent by the terminal; A search unit, configured to search for a target base station storing content matching the content identifier when there is no content matching the content identifier in the cache of the communication device; A sending unit, configured to send a request message carrying the content identifier to the target base station, so as to acquire content matching the content identifier from the target base station, and send the content to the terminal; wherein , the target base station is: a base station that communicates with the communication device. 12. The communication device according to claim 11, wherein a content index table is stored on both the communication device and the target base station, and the content index table includes information stored in the buffer memory of the communication device and the target base station. All content identifiers in the cache and the base station identifier corresponding to any content identifier. 13. The communication device according to claim 12, wherein the search unit is specifically configured to, when there is no content matching the content identifier in the cache of the communication device, search the content index table for the content matching the content identifier. The target base station identifier corresponding to the content identifier. 14. The communication device according to claim 13, wherein the search unit is specifically configured to find out in the content index table when there is no content matching the content identifier in the cache of the communication device When there are at least two base station identifiers corresponding to the content identifier, one base station identifier is selected from the at least two base station identifiers corresponding to the content identifier as the target base station identifier. 15. The communication device according to claim 12, further comprising: A first synchronization unit, configured to delete existing content identifiers in the content index table saved by the communication device when the existing content is deleted from the cache of the communication device, and send the changed content index table to the The target base station is used to instruct the target base station to synchronously change the content index table saved on the target base station to the changed content index table. 16. The communication device according to claim 12, further comprising: The second synchronization unit is configured to add a new content identifier to the content index table saved by the communication device when new content is added to the cache of the communication device, and send the changed content index table to the target The base station is configured to instruct the target base station to synchronously change the content index table saved on the target base station to the changed content index table. 17. The communication device according to any one of claims 11-16, wherein the communication device is specifically a base station. 18. A communication device, characterized in that it comprises: a receiving unit, configured to receive a request message carrying a content identifier sent by the source base station; an acquiring unit, configured to acquire content matching the content identifier in the cache of the communication device; A sending unit, configured to send the acquired content that matches the content identifier to the source base station, so that the source base station can send the content to the terminal; wherein, the source base station is: the same as the A base station for communication between communication devices. 19. The communication device according to claim 18, wherein the source base station and the communication device both store a content index table, and the content index table includes information stored in the source base station cache and the communication device All content identifiers in the cache and the base station identifier corresponding to any content identifier. 20. The communication device according to claim 19, further comprising: The first synchronization unit is configured to receive the changed content index table sent by the source base station, the changed content index table is obtained by the source base station after deleting the existing content identifier in the content index table saved by the source base station ; and synchronously change the content index table saved on the communication device to the changed content index table. 21. The communication device according to claim 19, further comprising: The second synchronization unit is configured to receive the changed content index table sent by the source base station, the changed content index table is obtained by the source base station after adding a new content identifier to the content index table saved by the source base station; and synchronously change the content index table saved on the communication device to the changed content index table. 22. The communication device according to any one of claims 18-21, wherein the communication device is specifically a target base station. 23. A base station system, characterized in that it comprises: a source base station and a target base station, wherein both the source base station and the target base station are provided with buffers; The source base station is configured to receive the request message carrying the content identifier sent by the terminal; when there is no content matching the content identifier in the cache of the source base station, search for a target base station that stores the content matching the content identifier ; sending a request message carrying the content identifier to the target base station, so as to acquire content matching the content identifier from the target base station, and send the content to the terminal; The target base station is configured to receive the request message carrying the content identifier sent by the source base station, acquire content matching the content identifier in the cache of the target base station, and send the acquired content to the The source base station; wherein, the target base station is: a base station that communicates with the source base station. 24. A base station system according to claim 23, characterized in that, both the source base station and the target base station store a content index table, and the content index table includes the content stored in the cache of each base station All content identifiers and the base station identifier corresponding to any content identifier. 25. The base station system according to any one of claims 23-24, wherein the source base station and the target base station are connected in a wireless mesh (Mesh) manner.