阅读说明：本技术 分布式移动网络视频缓存放置方法、系统及相关设备 (Distributed mobile network video cache placement method, system and related equipment ) 是由 袁健鑫 郭嘉帅 于 2021-09-26 设计创作，主要内容包括：本发明适用于网络通信技术领域,提供了一种分布式移动网络视频缓存放置方法、系统及相关设备,所述方法包括以下步骤：建立一个蜂窝网络的分布式缓存模型,蜂窝网络包括一个宏基站与多个微基站,蜂窝网络对覆盖范围内的微用户提供视频服务；微基站通过后悔最小值算法从宏基站中获取一个子视频数据并进行缓存放置；微基站通过概率算法对自己缓存的所有子视频数据计算受欢迎度,并根据受欢迎度对所述微基站中的子视频数据进行删除；所述微基站根据受欢迎度计算缓存概率,并将一个微基站中不存在的子视频数据在微基站中进行缓存。本发明解决了传统蜂窝网络无法在宏-微基站的蜂窝网络结构中降低移动视频数据传输延时的问题。(The invention is suitable for the technical field of network communication, and provides a distributed mobile network video cache placement method, a distributed mobile network video cache placement system and related equipment, wherein the method comprises the following steps: establishing a distributed cache model of a cellular network, wherein the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage area; the micro base station acquires sub video data from the macro base station through a regret minimum algorithm and performs cache placement; the micro base station calculates the popularity of all sub-video data cached by the micro base station through a probability algorithm, and deletes the sub-video data in the micro base station according to the popularity; and the micro base station calculates the caching probability according to the popularity and caches the sub-video data which does not exist in one micro base station in the micro base station. The invention solves the problem that the traditional cellular network can not reduce the transmission delay of the mobile video data in the cellular network structure of the macro-micro base station.)

1. A distributed mobile network video cache placement method is characterized by comprising the following steps:

establishing a distributed cache model of a cellular network, wherein the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network is used for providing video service for micro users in the coverage area of the cellular network;

the micro base station acquires sub video data from the macro base station based on a regret minimum algorithm and performs cache placement;

the micro base station calculates the popularity of all the sub-video data cached by the micro base station through a probability algorithm, and deletes the sub-video data in the micro base station according to the popularity and a preset rule;

and the micro base station calculates cache probability distribution according to the popularity and caches the sub-video data which does not exist in one micro base station in the micro base station.

2. The method as claimed in claim 1, wherein the macro base station in the cellular network includes a total video data, the total video data further includes a plurality of sub video data, the micro base station requests the sub video data from the macro base station and performs cache placement, and the micro base station is an access node facing the micro user.

3. The distributed mobile network video cache placement method of claim 2, wherein the distributed cache model is about a joint clustering and cache optimization problem, wherein:

defining the set of micro base stations in the cellular network as B, any one of the micro base stations in BRepresents;

defining a set of all said micro-users in said cellular network as，For any of the micro-usersRepresents;

defining the total video data in the macro base station asThe sub-video data hasThe number of the main components is one,for any one of the sub-video dataRepresents;

defining a micro user set served by the micro base station as U, wherein the number of the micro users in the U is S, and any one micro user in the U is usedRepresents;

defining the sum of the capacities of the cache spaces of all the micro base stations as C, wherein the cache space of any micro base station in C is；

Recording one piece of sub-video data cached from the macro base station to the local by the micro base station as；

According to the above, the total service delay of the micro-user requesting the sub-video data satisfies the following condition:

wherein the content of the first and second substances,representing said micro-users in relation to UFrom the micro base stationRequesting the sub video dataThe delay of (a) is set to be,representing the micro-userRequested the first-said sub-video data;

defining an association vector between the micro-user and the micro base station as，Represented as the micro-userThe micro base station providing serviceIn accordance with the above, the distributed caching model for the federated cluster and cache optimization problem satisfies the following expression:

wherein the content of the first and second substances,a minimum delay value representing a cache optimization problem,representsAny one of the micro usersAnd the micro base stationThe relationship between the two or more of them,representsAny one of the micro usersAnd the micro base stationRequest firstA relationship between each of the sub-video data,representing the micro base stationThe buffer space capacity of (2).

4. The distributed mobile network video cache placement method according to claim 3, wherein said cellular network step for providing video services to micro-users within its coverage area comprises the sub-steps of:

the micro base station acquires the presence of the micro usertA request for acquiring first sub-video data is sent to the terminal at the moment;

the micro base station requests the macro base station to acquire the first sub video data corresponding to the request in the total video data, and caches the first sub video data;

and the micro base station sends the first sub video data cached and placed by the micro base station to the micro user.

5. The method for video cache placement in a distributed mobile network according to claim 4, wherein the step of acquiring a sub-video data from the macro base station by the micro base station through a regret minimum algorithm and performing cache placement specifically includes the sub-steps of:

in the above-mentionedtThe next moment of time, the micro base station is based on the timetCalculating the regret minimum value of the first sub-video data requested by the micro-user at the moment;

and the micro base station selects one second sub video data from the total video data of the macro base station according to the regret minimum value for cache placement.

6. The distributed mobile network video cache placement method of claim 5, wherein said micro base station is based on saidThe step of calculating the regret minimum value of the first sub-video data requested by the micro user at the moment specifically includes:

define the regret vector asAnd a utility vector corresponding to the regret vector；

Defining the micro base station asThe action of acquiring one sub video data from the total video data at any moment isWherein, in the step (A),is the total number of operations and,is equal to the total video dataThe total number of the sub video data in (a);

definition ofIs the micro base stationIn the above-mentionedExecuting the action at a timeThe probability of (d);

according to the above, the micro base stationPerforming the actionThe probability calculation formula satisfies the following conditions:

wherein the content of the first and second substances,a probability result calculated for the probability calculation formula,is the boltzmann regret temperature coefficient controlling the probability calculation formula,representing a positive regret vector, and each parameter in the above conditions further satisfies:

wherein the content of the first and second substances,is referred to inThe instantaneous observed utility function at the time immediately preceding the time,is a learning parameter for calculation, and:

satisfy the above constraint stripAnd (3) a component.

7. The distributed mobile network video cache placement method according to claim 6, wherein said micro base station calculates popularity for all the sub video data cached by itself through a probabilistic algorithm, and the step of deleting the sub video data in the micro base station according to the popularity specifically comprises the sub-steps of:

at each one of saidAt the moment, the micro base station calculates the popularity of all the sub-video data cached by the micro base station for the micro user;

and the micro base station sorts all the sub video data according to the popularity.

8. The distributed mobile network video cache placement method according to claim 7, wherein said micro base station calculates said popularity for said micro user for all said sub video data cached by itself by specifically:

defining each of the micro base stations to request frequency of each of the sub-video data based on its service domain asWherein the requested frequency of the sub video data in any of the micro base stations satisfies:

wherein the content of the first and second substances,representing the micro-users in the cellular networkBuffer space to the micro base stationThe frequency of the request for the content is,representing the micro-users in the cellular networkBuffer space to the micro base stationThe frequency of requests for content;

according to the above, the calculation process of the cache deletion probability with respect to the request frequency to obtain the popularity satisfies the following condition:

wherein the content of the first and second substances,it is the buffer update factor that is updated,in order to give the sub video data, which is requested less frequently, a higher probability.

9. The distributed mobile network video cache placement method according to claim 8, wherein said micro base station calculates popularity for all of said sub video data cached by itself through a probabilistic algorithm, and the step of deleting said sub video data in said micro base station according to said popularity further comprises the sub-steps of:

if the cache space of the micro base station is enough to store another sub video data, the micro base station does not perform any operation;

and if the cache space of the micro base station is not enough to store another piece of sub-video data, the micro base station deletes the sub-video data with lower use frequency according to the size of the cache space.

10. The method as claimed in claim 9, wherein the micro base station calculates a buffering probability according to the popularity, and the step of buffering the sub-video data that does not exist in one of the micro base stations in the micro base station specifically includes the following sub-steps:

at each one of saidtAt the moment, the micro base station is based on thetCalculating the cache probability of the popularity of all the sub-video data cached in the previous moment of the moment;

and the micro base station selects the sub video data which does not exist in the cache space from the macro base station according to the cache probability for cache placement.

11. The distributed mobile network video cache placement method of claim 10, wherein said at each of said plurality of video buffersAt the moment, the micro base station is based on theThe process of calculating the cache probability of the popularity of all the sub-video data cached by the client at the previous moment of time specifically comprises the following steps:

defining the cache probability distribution asAnd the following conditions are satisfied:

the result of (c) is that the regret vector is calculated as a function of the regret vectorThe micro user is towards the micro base station at the momentA buffering probability distribution of the requested sub video data.

12. A distributed mobile network video cache placement system is characterized by comprising the following modules:

the distributed cache model establishing module is used for establishing a distributed cache model of a cellular network, the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage area;

the expected cache placement module is used for controlling the micro base station to acquire sub video data from the macro base station through a regret minimum algorithm and performing cache placement;

the cache deleting module is used for controlling the micro base station to calculate the popularity of all the sub-video data cached by the micro base station through a probability algorithm and deleting the sub-video data in the micro base station according to the popularity;

and the cache updating module is used for controlling the micro base stations to calculate cache probability according to the popularity and caching the sub-video data which does not exist in one micro base station in the micro base station.

13. A computer device, comprising: memory, processor and computer program stored on the memory and executable on the processor, the processor implementing the steps in the distributed mobile network video cache placement method according to any of claims 1 to 11 when executing the computer program.

14. A computer-readable storage medium, having stored thereon a computer program which, when being executed by a processor, carries out the steps of the distributed mobile network video cache placement method according to any one of claims 1 to 11.

Technical Field

The invention is applicable to the technical field of network communication, and particularly relates to a distributed mobile network video cache placement method, a distributed mobile network video cache placement system and related equipment.

Background

In a conventional cellular network, a mobile terminal in the cellular network can only obtain requested content from a macro base station, which is equivalent to that when the conventional cellular network is constructed, devices in the cellular network form a star network structure with the macro base station as a center, which has high requirements on the bearing capacity of the macro base station, and reaches a performance bottleneck along with the increase of the number of mobile terminal devices in the cellular network.

In the wireless heterogeneous cellular network, by introducing the cell base station with content caching capability, the backhaul link load of the cellular base station can be reduced by using the micro base station with caching capability for local caching, and the utilization rate of the cached content is improved, which increases the carrying capability of the cellular network structure to a certain extent. However, with the development of the internet, the data is growing explosively, so that the challenge of storing massive multimedia contents in the cache of the micro base station of the mobile video distribution network needs to be faced with the limited node cache space, mainly because the mobile video has become the main data type in the internet, and meanwhile, the requirements of users on the picture quality and the transmission time of the mobile video become higher, and if the load capacity of the cellular network is improved by introducing the micro base station only, the delay requirement of the mobile video cannot be solved.

Disclosure of Invention

The embodiment of the invention provides a distributed mobile network video cache placement method, a distributed mobile network video cache placement system and related equipment, and aims to solve the problem that a traditional cellular network cannot reduce the transmission delay of mobile video data in a cellular network structure of a macro-micro base station.

The embodiment of the invention provides a distributed mobile network video cache placement method, which comprises the following steps:

establishing a distributed cache model of a cellular network, wherein the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage area;

the micro base station acquires sub video data from the macro base station through a regret minimum algorithm and performs cache placement;

the micro base station calculates the popularity of all the sub-video data cached by the micro base station through a probability algorithm, and deletes the sub-video data in the micro base station according to the popularity;

and the micro base station calculates the caching probability according to the popularity and caches the sub-video data which does not exist in one micro base station in the micro base station.

Further, the macro base station in the cellular network includes a total video data, the total video data further includes a plurality of sub video data, the micro base station requests the sub video data from the macro base station and performs cache placement, and the micro base station is an access node facing the micro user.

Still further, the distributed caching model is directed to a joint clustering and caching optimization problem, wherein:

defining the set of micro base stations in the cellular network as B, any one of the micro base stations in BbRepresents;

defining a set of all said micro-users in said cellular network as，For any of the micro-usersmRepresents;

defining the total video data in the macro base station as V, the sub video data havingFor any one of the sub-video data of VRepresents;

defining a micro user set served by the micro base station as U, wherein the number of the micro users in the U is S, and any one micro user in the U is usedRepresents;

defining the sum of the capacities of the cache spaces of all the micro base stations as C, wherein the cache space of any micro base station in C is；

Recording one piece of sub-video data cached from the macro base station to the local by the micro base station as；

According to the above, the total service delay of the micro-user requesting the sub-video data satisfies the following condition:

wherein the content of the first and second substances,representing said micro-users in relation to UFrom the micro base stationRequesting the sub video dataThe delay of (a) is set to be,representing the micro-userRequested the firstThe sub video data.

Defining the association vector between the micro user and the micro base station asRepresented as the micro-userThe micro base station providing serviceIn accordance with the above, the distributed caching model for the federated cluster and cache optimization problem satisfies the following expression:

wherein the content of the first and second substances,a minimum delay value representing a cache optimization problem,representsAny one of the micro usersAnd the micro base stationThe relationship between the two or more of them,representsAny one of the micro usersAnd the micro base stationRequest firstA relationship between each of the sub-video data,representing the micro base stationThe buffer space capacity of (2).

Further, the step of the cellular network providing video service to the micro users in the coverage area specifically includes the following sub-steps:

the micro-user is atRequesting to acquire first sub-video data from the micro base station at the moment;

the micro base station requests the macro base station to acquire the first sub video data corresponding to the request in the total video data, and caches the first sub video data;

and the micro base station sends the first sub video data cached and placed by the micro base station to the micro user.

Further, the step of acquiring, by the micro base station, one sub-video data from the macro base station by using a regret minimum algorithm and performing cache placement specifically includes the following sub-steps:

in the above-mentionedThe next moment of time, the micro base station is based on the timeCalculating the regret minimum value of the first sub-video data requested by the micro-user at the moment;

and the micro base station selects one second sub video data from the total video data of the macro base station according to the regret minimum value for cache placement.

Further, the micro base station is based on the aboveThe step of calculating the regret minimum value of the first sub-video data requested by the micro user at the moment specifically includes:

define the regret vector asAnd a utility vector corresponding to the regret vector；

Defining the micro base station asThe action of acquiring one sub video data from the total video data at any moment isWherein, in the step (A),is the total number of operations and,equal to the total number of said sub-video data in said total video data V;

definition ofIs the micro base stationIn the above-mentionedExecuting the action at a timeThe probability of (d);

according to the above, the micro base stationPerforming the actionThe probability calculation formula satisfies the following conditions:

wherein the content of the first and second substances,a probability result calculated for the probability calculation formula,is the boltzmann regret temperature coefficient controlling the probability calculation formula,representing a positive regret vector, and each parameter in the above conditions further satisfies:

wherein the content of the first and second substances,is referred to inThe instantaneous observed utility function at the time immediately preceding the time,is a learning parameter for calculation, and:

the above constraint is satisfied.

Furthermore, the step of the micro base station calculating the popularity of all the sub-video data cached by the micro base station through a probability algorithm and deleting the sub-video data in the micro base station according to the popularity specifically comprises the following sub-steps:

at each one of saidAt the moment, the micro base station calculates the popularity of all the sub-video data cached by the micro base station for the micro user;

and the micro base station sorts all the sub video data according to the popularity.

Further, the step of the micro base station calculating the popularity of the micro user for all the sub video data cached by the micro base station specifically comprises:

defining each of the micro base stations to request frequency of each of the sub-video data based on its service domain asWherein the requested frequency of the sub video data in any of the micro base stations satisfies:

wherein the content of the first and second substances,representing the micro-users in the cellular networkBuffer space to the micro base stationThe frequency of the request for the content is,representing the micro-users in the cellular networkBuffer space to the micro base stationThe frequency of requests for content;

according to the above, the calculation process of the cache deletion probability with respect to the request frequency to obtain the popularity satisfies the following condition:

wherein the content of the first and second substances,it is the buffer update factor that is updated,in order to give the sub video data, which is requested less frequently, a higher probability.

Furthermore, the micro base station calculates the popularity of all the sub-video data buffered by the micro base station through a probability algorithm, and the step of deleting the sub-video data in the micro base station according to the popularity further comprises the following sub-steps:

if the cache space of the micro base station is enough to store another sub video data, the micro base station does not perform any operation;

and if the cache space of the micro base station is not enough to store another piece of sub-video data, the micro base station deletes the sub-video data with lower use frequency according to the size of the cache space.

Further, the step of the micro base station calculating the caching probability according to the popularity, and caching the sub-video data that does not exist in one micro base station in the micro base station specifically includes the following sub-steps:

at each one of saidAt the moment, the micro base station is based on theCalculating the cache probability of the popularity of all the sub-video data cached in the previous moment of the moment;

and the micro base station selects the sub video data which does not exist in the cache space from the macro base station according to the cache probability for cache placement.

Further, said at each of saidAt the moment, the micro base station is based on theThe process of calculating the cache probability of the popularity of all the sub-video data cached by the client at the previous moment of time specifically comprises the following steps:

defining the cache probability distribution asAnd the following conditions are satisfied:

m _b (t)the result of (c) is that the regret vector is calculated as a function of the regret vectorThe micro user is towards the micro base station at the momentA buffering probability distribution of the requested sub video data.

In a second aspect, an embodiment of the present invention further provides a distributed mobile network video cache placement system, including the following modules:

the distributed cache model establishing module is used for establishing a distributed cache model of a cellular network, the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage area;

the expected cache placement module is used for controlling the micro base station to acquire sub video data from the macro base station through a regret minimum algorithm and performing cache placement;

the cache deleting module is used for controlling the micro base station to calculate the popularity of all the sub-video data cached by the micro base station through a probability algorithm and deleting the sub-video data in the micro base station according to the popularity;

and the cache updating module is used for controlling the micro base stations to calculate cache probability according to the popularity and caching the sub-video data which does not exist in one micro base station in the micro base station.

In a third aspect, an embodiment of the present invention further provides a computer device, including: a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the steps in the distributed mobile network video cache placement method as described in any of the above embodiments when executing the computer program.

In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when executed by a processor, the computer program implements the steps in the distributed mobile network video cache placement method according to any one of the foregoing embodiments.

The method has the advantages that the video data cache placement method based on the regret minimum value is designed in the macro-micro base station structure, and the video data in the cache space of the micro base station is cleaned and prestored by combining the probability algorithm, so that the problem of high transmission delay of the mobile video data in the cellular network is solved.

Drawings

Fig. 1 is a scene schematic diagram of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 2 is a flowchart of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 3 is a block diagram of a sub-flow of step S101 of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 4 is a block diagram of a sub-flow of step S102 of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 5 is a block diagram of a sub-flow of step S103 of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 6 is a block diagram of a sub-flow of step S104 of a distributed mobile network video cache placement method according to an embodiment of the present invention;

fig. 7 is a block diagram of a distributed mobile network video cache placement system according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a computer device provided by an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, fig. 1 is a scene schematic diagram of a method for placing a video cache in a distributed mobile network according to an embodiment of the present invention, in an embodiment of the present invention, a macro base station and a plurality of micro base stations are deployed in a cell where a cellular network is located, where the cell has a plurality of micro users, and the micro users obtain other network communication terminals through an intelligent terminal device to connect to the cellular network formed by the macro base station and the micro base stations so as to connect to the network and obtain services provided by the cellular network.

Referring to fig. 2, fig. 2 is a flowchart of a method for placing a video cache in a distributed mobile network according to an embodiment of the present invention, which specifically includes the following steps:

s101, establishing a distributed cache model of a cellular network, wherein the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage area.

Referring to fig. 3, fig. 3 is a sub-flow diagram of step S101 of the distributed mobile network video cache placement method according to the embodiment of the present invention, which specifically includes the following sub-steps:

s1011, the micro-user isAnd requesting the micro base station to acquire first sub-video data at the moment.

In this embodiment of the present invention, the cellular network provides video services to the micro users, and specifically, in consideration of the diversity of video content in the cellular network, it is assumed that the macro base station includes video data that may be needed by all the micro users, and the video data is defined as total video data, that is, all the video content in the cellular network is owned by the macro base station, and the total video data is composed of a plurality of sub video data; the micro base station is a structure for assisting the macro base station to realize data distribution, that is, the micro base station does not have the total video data in the macro base station at first, but the density of the micro base station is large, and the coverage area is largeThe distance to the micro-user is smaller and therefore the micro base station is designed to serve the micro-user directly. When the micro-user needs to acquire certain video data, the micro-user is assumed to be in the video dataA request is sent to the micro base station at a moment in time, and no video data is cached in the micro base station yet, then the micro base station sends a request to the micro base station at the moment in timeAnd defining the video data requested by the micro user at the moment as first sub video data.

S1012, the micro base station requests the macro base station to acquire the first sub video data corresponding to the request in the total video data, and the first sub video data is placed in a cache.

And the micro base station acquires the sub video data corresponding to the first sub video data from the total video data of the macro base station according to the request content of the first sub video data, and caches the sub video data in a cache space of the micro base station.

And S1013, the micro base station sends the first sub-video data cached by the micro base station to the micro user.

After the micro base station acquires the first sub-video data, the first sub-video data existing in the cache space of the micro base station is sent to the micro user so as to finish the current timeA request of the micro-user of a moment of time.

In the embodiment of the present invention, a distributed cache model of the cellular network is established according to the operation logic of the above steps, where a set of the micro base stations in the cell is defined as B, any one of the micro base stations in B is represented by B, and a set of all the micro users in the cellular network is defined as，For any of the micro-usersRepresents, the micro-userThe positions in the cell are uniformly and randomly distributed, according to the operation logic of the steps, the micro base station has a cache space and has cache capacity, the cache object of the micro base station is the sub video data contained in the total video data in the macro base station, and the quantity of the sub video data is defined asThe total video data is a setThen the total video data may be expressed as:

wherein the content of the first and second substances,representing the total video dataAny one of the sub-video data.

Defining a subset of said micro users served by one of said micro base stations as a set of micro users, denoted asWherein the number of micro users isThen the micro user setCan be expressed as:

wherein the content of the first and second substances,representing any of the micro users in the set of micro users.

Defining the capacity of the buffer space of all the micro base stations asThen the capacity of the buffer space of all the micro base stationsCan be expressed as:

the micro base stationbObtaining and caching the sub-video data from the macro base station to the localFromNamely:

a certain one of the sub video data requested by the micro userContent of (2)FromThe probability of (D) follows a cedar distribution with mean values。

In summary, the main objective of the micro base station in the embodiment of the present invention is to find the optimal buffering policy that minimizes the total service delay of the micro user for requesting the sub video data, wherein the total service delay can be expressed by the following conditions:

the micro-users send requests to the micro base station which is closest to the micro-users, and each micro base station provides services for a plurality of micro-users which are close to each other, so that the micro base station can minimize the total service delay according to the micro base stationAt the moment, the content of the sub video data requested by the micro user needs to calculate and cache the content of the sub video data requested by the micro user possibly. Definition ofFor the association vector between the micro user and the micro base station, the following expression is made to hold:

wherein the content of the first and second substances,represented as the micro-userThe micro base station providing service。

The distributed caching model of the cellular network with respect to the joint clustering and caching optimization problem, according to the above definition, is as follows:

s102, the micro base station acquires sub video data from the macro base station through a regret minimum algorithm and caches the sub video data.

Referring to fig. 4, fig. 4 is a sub-flowchart of step S102 of the method for placing a video cache in a distributed mobile network according to the embodiment of the present invention, which specifically includes the following sub-steps:

s1021, theThe micro base station is based on the timeAnd calculating the regret minimum value of the first sub-video data requested by the micro user at the previous moment of the moment.

In the above-mentionedAt the time of day, the micro base stationWill follow the operation spaceIn which an action is selectedWherein the operation spaceComprises the following steps:

the actionsBuffer-storing said sub-video data for one or notThe binary value of the buffering operation is performed. Wherein the content of the first and second substances,is a total number of operations that is equal to the total number of sub-video data in the total video data V.

The micro base station distributes according to an action probabilitySelecting one of the actionsThe action probability distributionComprises the following steps:

wherein the content of the first and second substances,is the micro base stationIn the above-mentionedExecuting the action at a timeThe probability of (c).

Each of the micro base stations is based on the vectorUpdating its own actions, wherein each of said micro base stations selects a probability distribution to minimize a regret vector of whether said micro base station caches a certain one of said sub-video dataThe regret vectorThe method specifically comprises the following steps:

wherein the content of the first and second substances,representing the micro base stationIn the above-mentionedtAll time instants preceding the time instantWherein the same action is performed。

In addition, the micro base stationWill also be estimating the regret vectorWhile simultaneously estimating utility vectorsThe utility vectorComprises the following steps:

s1022, the micro base station selects a second sub video data from the total video data of the macro base station according to the regret minimum value for cache placement.

According to the definition in the step S1021, the Gibbs-Sa-based method is adoptedmprobability distribution of pling (Gibbs sampling) to perform the actionThen, the micro base stationPerforming the actionThe probability calculation formula of (a) can be expressed as:

wherein the content of the first and second substances,a probability result calculated for the probability calculation formula,is the boltzmann regret temperature coefficient controlling the probability calculation formula,representing a positive regret vector, the positive regret vectorComprises the following steps:

in the above-mentionedTime of day, the micro base stationEstimating the regret vector using a regret minimum based calculation processThe utility vectorAnd the action probability distributionThe specific process of (2) satisfies the following conditions:

wherein the content of the first and second substances,is referred to inThe instantaneous observed utility function at the time immediately preceding the time,is a learning parameter for the purpose of calculation,the following constraints are satisfied:

according to the above constraint conditions, the probability calculation formula can be converged to oneAnd (4) coarse correlation balance.

According to the calculation result of the probability calculation formula, the micro base station caches one piece of sub-video data from the macro base station as the sub-video dataThe buffered second sub-video data of a time instant.

S103, the micro base station calculates the popularity of all the sub-video data cached by the micro base station through a probability algorithm, and deletes the sub-video data in the micro base station according to the popularity.

Referring to fig. 5, fig. 5 is a sub-flowchart of step S103 of the method for placing a video cache in a distributed mobile network according to the embodiment of the present invention, which specifically includes the following sub-steps:

s1031, inAt the moment, the micro base station calculates the popularity of the micro user for all the sub video data cached by the micro base station.

In the above-mentionedAt the moment, each micro base station acquires the popularity of all the sub-video data in the current service domain, wherein each micro base station is based on each sub-video data in the service domainFrequency of request ofTo build a popularity, said request frequency being different for each of said micro base stations, defining said request frequencyComprises the following steps:

wherein the content of the first and second substances,representing the micro-users in the cellular networkBuffer space to the micro base stationThe frequency of the request for the content is,representing the micro-users in the cellular networkBuffer space to the micro base stationcThe frequency of requests for content;

then based on Gibbs-Sa according to the value of the requested frequencymprobability distribution of pling the conditions for calculating the cache deletion probability are as follows:

wherein the content of the first and second substances,it is the buffer update factor that is updated,in order to give the sub video data, which is requested less frequently, a higher probability. Gibbs-SamUse of pling probability distribution allows useParameter update cache delete strategy when usedEqual to 0, the probability of performing deletion of all the sub-video data is the same, and higherThe value indicates that the sub-video data whose request frequency is low is to be deleted with a high probability.

S1032, the micro base station sorts all the sub video data according to the popularity.

And each micro base station sorts all the sub-video data in the cache space according to the popularity obtained by calculation and the calculation result of the cache deletion probability by combining the popularity and the calculation result of the cache deletion probability so as to carry out the next step.

S1033a, if the buffer space of the micro base station is still enough to store another sub video data, the micro base station does not perform any operation.

After calculating the cache deletion probability corresponding to the sub-video data in each cache, the micro base station checks the size of the cache space of the micro base station. In this embodiment of the present invention, the total video data of the macro base station is composed of N pieces of the sub video data, and the buffer spaces occupied by the N pieces of the sub video data are equal in size. If the cache space of the micro base station is still enough to store the sub-video data which is not cached, the micro base station does not execute the deleting operation.

S1033b, if the buffer space of the micro base station is not enough to store another piece of sub-video data, the micro base station deletes the sub-video data with the lower frequency of use according to the size of the buffer space.

And if the result obtained by the micro base station examination indicates that the cache space of the micro base station is not enough to cache a new sub-video data, the micro base station selects the sub-video data with the maximum cache deletion probability from the cache space to delete according to the sequencing result of the cache deletion probability.

S104, the micro base stations calculate the caching probability according to the popularity, and cache the sub video data which does not exist in one micro base station in the micro base station.

Referring to fig. 6, fig. 6 is a sub-flow diagram of step S104 of the distributed mobile network video cache placement method according to the embodiment of the present invention, which specifically includes the following sub-steps:

s1041, inAt the moment, the micro base station is based on theAnd calculating the cache probability of the popularity of all the sub-video data cached in the previous moment of the moment.

In the above-mentionedAt the time of day, the micro base stationWill perform one of the actionsAccording to saidThe action actually occurring at the last moment of timeCalculating the actual delay of the micro user for acquiring the sub video data, thereby obtaining the actual utility of the micro base station。

According to the actual utility, the micro base stationComputing the using iterative updatesThe utility vector of a time of dayAnd said regret vectorAnd calculating the regret vector according to the regret vectorCache probability distribution of the sub-video data requested by the micro-user at a timeSaid cache probability distributionThe following conditions are satisfied:

s1042, the micro base station selects the sub video data which does not exist in the cache space from the macro base station according to the cache probability to perform cache placement.

The micro base stationAccording to the calculated cache probability distributionSelecting one of the micro base stations from the total video data of the macro base stationDoes not exist in the buffer space, and buffers the sub-video data.

The video cache placement method of the distributed mobile network according to the embodiment of the invention designs a video data cache placement strategy based on the regret minimum value in the structure of the macro-micro base station, and combines a probability algorithm to clean and pre-store the video data in the cache space of the micro base station, thereby solving the problem of high transmission delay of the mobile video data in the cellular network.

The embodiment of the present invention further provides a distributed mobile network video cache placement system, please refer to fig. 7, where fig. 7 is a structural block diagram of the distributed mobile network video cache placement system provided in the embodiment of the present invention, and the distributed mobile network video cache placement system 200 includes a distributed cache model establishment module 201, an expected cache placement module 202, a cache deletion module 203, and a cache update module 204, where:

the distributed cache model establishing module 201 is configured to establish a distributed cache model of a cellular network, where the cellular network includes a macro base station and multiple micro base stations, and the cellular network provides a video service to micro users within a coverage area;

the expected cache placement module 202 is configured to control the micro base station to obtain sub video data from the macro base station through a regret minimum algorithm and perform cache placement;

the cache deletion module 203 is configured to control the micro base station to calculate popularity of all the sub-video data cached by the micro base station through a probability algorithm, and delete the sub-video data in the micro base station according to the popularity;

the cache updating module 204 is configured to control the micro base station to calculate a cache probability according to the popularity, and cache the sub-video data that does not exist in one micro base station in the micro base station.

The distributed mobile network video cache placement system 700 provided in the embodiment of the present invention can implement the steps in the distributed mobile network video cache placement method in the above-mentioned embodiment, and can implement the same technical effects, and details are not repeated herein with reference to the description in the above-mentioned embodiment.

An embodiment of the present invention further provides a computer device, please refer to fig. 8, where fig. 8 is a schematic diagram of a computer device provided in an embodiment of the present invention, and the computer device 300 includes: a memory 302, a processor 301, and a computer program stored on the memory 302 and executable on the processor 301.

The processor 301 calls a computer program stored in the memory 302 to execute the steps in the method for placing the video cache of the distributed mobile network according to the embodiment of the present invention, and with reference to fig. 1, the method specifically includes:

s101, establishing a distributed cache model of a cellular network, wherein the cellular network comprises a macro base station and a plurality of micro base stations, and the cellular network provides video service for micro users in a coverage range;

further, the macro base station in the cellular network includes a total video data, the total video data further includes a plurality of sub video data, the micro base station requests the sub video data from the macro base station and performs cache placement, and the micro base station is an access node facing the micro user.

Further, the step of the cellular network providing video service to the micro users in the coverage area specifically includes the following sub-steps:

the micro-user is atRequesting to acquire first sub-video data from the micro base station at the moment;

the micro base station requests the macro base station to acquire the first sub video data corresponding to the request in the total video data, and caches the first sub video data;

and the micro base station sends the first sub video data cached and placed by the micro base station to the micro user.

S102, the micro base station acquires sub video data from the macro base station through a regret minimum algorithm and caches the sub video data;

further, the step of acquiring, by the micro base station, one sub-video data from the macro base station by using a regret minimum algorithm and performing cache placement specifically includes the following sub-steps:

in the above-mentionedtThe next moment of time, the micro base station is based on the timetCalculating the regret minimum value of the first sub-video data requested by the micro-user at the moment;

and the micro base station selects one second sub video data from the total video data of the macro base station according to the regret minimum value for cache placement.

S103, the micro base station calculates the popularity of all the sub-video data cached by the micro base station through a probability algorithm, and deletes the sub-video data in the micro base station according to the popularity;

furthermore, the step of the micro base station calculating the popularity of all the sub-video data cached by the micro base station through a probability algorithm and deleting the sub-video data in the micro base station according to the popularity specifically comprises the following sub-steps:

at each one of saidAt the moment, the micro base station calculates the popularity of all the sub-video data cached by the micro base station for the micro user;

and the micro base station sorts all the sub video data according to the popularity.

Furthermore, the micro base station calculates the popularity of all the sub-video data buffered by the micro base station through a probability algorithm, and the step of deleting the sub-video data in the micro base station according to the popularity further comprises the following sub-steps:

if the cache space of the micro base station is enough to store another sub video data, the micro base station does not perform any operation;

and if the cache space of the micro base station is not enough to store another piece of sub-video data, the micro base station deletes the sub-video data with lower use frequency according to the size of the cache space.

S104, the micro base stations calculate the caching probability according to the popularity, and cache the sub video data which does not exist in one micro base station in the micro base station.

Further, the step of the micro base station calculating the caching probability according to the popularity, and caching the sub-video data that does not exist in one micro base station in the micro base station specifically includes the following sub-steps:

at each one of saidAt the moment, the micro base station is based on theCalculating the cache probability of the popularity of all the sub-video data cached in the previous moment of the moment;

and the micro base station selects the sub video data which does not exist in the cache space from the macro base station according to the cache probability for cache placement.

The computer device provided in the embodiment of the present invention can implement the steps in the distributed mobile network video cache placement method in the above embodiments, and can implement the same technical effects, and details are not repeated herein with reference to the description in the above embodiments.

The embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements each process and step in the distributed mobile network video cache placement method provided in the embodiment of the present invention, and can implement the same technical effect, and in order to avoid repetition, details are not repeated here.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Wherein the storage medium can be a magnetic disk, an optical disk, a Read-Only memory (Read-Only)Memory，ROM) Or random access memory (Rando)m Access Memory abbreviated as RAM) And the like.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. With this understanding in mind, the technical solutions of the present invention may be embodied in the form of a software product stored on a storage medium (e.g., RO)M/RAMMagnetic disk, optical disk) including instructions for enabling a terminal (such as a mobile phone, a computer, a server, an air conditioner, or a network device)) The method described in the various embodiments of the present invention is performed.

While the present invention has been described with reference to the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, which are illustrative, but not restrictive, and that various changes may be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.