WO2017084103A1

WO2017084103A1 - Method and apparatus for determining network topology structure

Info

Publication number: WO2017084103A1
Application number: PCT/CN2015/095210
Authority: WO
Inventors: 孙越; 宋令阳
Original assignee: 华为技术有限公司
Priority date: 2015-11-20
Filing date: 2015-11-20
Publication date: 2017-05-26

Abstract

Provided are a method and apparatus for determining a network topology structure. The method comprises: determining a network topology structure, wherein the network topology structure comprises N nodes and a D2D connection between each pair of nodes; computing respective first weights of two first nodes connected by means of the D2D connection, and assuming respective second weights of the two first nodes after the D2D connection is deleted; if the second weights of the two first nodes are both greater than the corresponding first weights, deleting the D2D connection; and determining whether to continue to delete the D2D connection or add a D2D connection until the network topology structure is a Nash equilibrium network topology structure. The weights are determined according to the costs of nodes corresponding to the weights in downloading data via a cellular network, the costs of data sharing by means of a D2D connection, a desired value of the number of D2D connections capable of being realized from other nodes to this node, and a desired value of the number of D2D connections capable of being realized from this node to other nodes, so that the accuracy of a network topology structure is improved.

Description

Method and device for determining network topology

Technical field

The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method and an apparatus for determining a network topology.

Background technique

With the large-scale growth of smart devices and the increasing popularity of mobile applications, mobile communications will continue to show rapid growth in the future. In order to cope with this fast-growing mobile data demand, operators have proposed many solutions, such as upgrading existing networks and adopting more complementary network technologies. Among them, the complementary network technology here may be Wireless Fidelity (WIFI), Device To Device (D2D), etc. This complementary network technology may also be called an opportunistic communication technology.

Data sharing between devices can be achieved through the cooperation of the cellular network and the above complementary network technologies. On the one hand, this solution can make better use of existing base station equipment while reducing the burden on the cellular network; on the other hand, this solution has the advantages of lower price and higher transmission rate. User terminals are also very attractive. Due to the simultaneous existence of the cellular network and the complementary network technology, the network topology of the prior art also changes. For example, each user terminal and the device of the base station serve as a network node, and a cellular network exists between the user terminal and the base station, and each user Communication between terminals can also be achieved through D2D. Usually, connections between nodes are used to indicate that there is a physical or logical connection between them.

In the prior art, in order to optimize the network, for example, the network bandwidth is maximized or the delay is minimized, it is generally assumed that in the network topology, as long as the conditions of the above-mentioned opportunistic communication technology are met, for example, two user terminals are satisfied. The D2D coverage condition is that there must be a connection between the nodes corresponding to the two user terminals in the network topology. However, in reality, there may be a "selfish" user terminal. The so-called "selfishness" means that the user terminal does not share its own data to all user terminals or any one due to cost, time, preference, and the like. User terminal, etc. Therefore, the network topology in the prior art differs from the actual situation.

Therefore, the network topology in the prior art is not accurate enough, thereby reducing the accuracy of network optimization.

Summary of the invention

The embodiment of the invention provides a method and a device for determining a network topology, thereby improving the accuracy of the network topology and improving the accuracy of the network optimization.

In a first aspect, an embodiment of the present invention provides a method for determining a network topology, including:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Calculating a first weight of each of the two first nodes connected to each D2D connection, and calculating a second weight of each of the two first nodes after deleting the D2D connection;

If the second weight of each of the two first nodes is greater than the corresponding first weight, deleting the D2D connection between the two first nodes from the network topology;

Determine whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology according to the deleted network topology until the deleted or added network topology is a Nash balanced network topology;

Wherein the weight is determined by v _c , n ^to , v _d and n ^from , wherein the v _c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and the n ^to represents the weight from the other node to the node The expected value of the number of D2D connections that can be implemented by the corresponding node, the v _d represents the cost of data sharing through the D2D connection, and the n ^from represents the D2D connection that can be implemented from the node corresponding to the weight to the other node. The expected value of the number.

Since the weight is determined by v _c , n ^to , v _d and n ^from , the cost of downloading data through the cellular network, the expected value of the number of D2D connections achievable from the other node to the node corresponding to the weight, through the D2D connection The cost of data sharing, and the expected value of the number of D2D connections that can be implemented from the node corresponding to the weight to other nodes, can be understood as taking into account the "selfishness" of the user terminal, such as when the user terminal Reluctant to share their own data to other user terminals, that is, the user terminal is more selfish, so the cost of data sharing through D2D connection can be increased, so that the finally obtained network topology is closer to reality, and the network topology is improved. The accuracy of the structure, which in turn improves the accuracy of network optimization.

Further, the determining, according to the deleted network topology, whether to continue to delete the D2D connection in the network topology or to increase the D2D connection in the network topology, specifically includes: If the deleted network topology is the Nash balanced network topology, the process ends; otherwise, the D2D connection in the network topology is continued to be deleted or the D2D connection in the network topology is increased.

Further, the increasing the D2D connection in the network topology specifically includes: calculating a third weight of each of the two second nodes that do not have a D2D connection, and adding a D2D between the two second nodes. After the connection, calculating a fourth weight of each of the two second nodes; if the fourth weight of each of the two second nodes is greater than the corresponding third weight, increasing between the two second nodes D2D is connected to the network topology. By calculating the third weight and the fourth weight, it is possible to accurately determine whether to increase the D2D connection in the network topology.

Optionally, the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein, the profit of the node g=v _c ·n ^to , the cost c=v _d ·n ^from , v _d <v _c .

Wherein the revenue of the node

cost

v _d <v _c , ω _i represents the preference weight of the node corresponding to the weight to the node i, and ω _j represents the preference weight of the node corresponding to the weight to the node j.

The above two alternative methods, that is, the cost of downloading data through the cellular network, the expected value of the number of D2D connections that can be realized from other nodes to the node corresponding to the weight, the cost of data sharing through the D2D connection, and the The expected value of the number of D2D connections that can be implemented by the node corresponding to the weight to other nodes is taken into consideration, so that the finally obtained network topology is closer to reality, the accuracy of the network topology is improved, and the accuracy of the network optimization is improved.

In a second aspect, an embodiment of the present invention provides a method for determining a network topology, including:

Determining a first cumulative number of D2D connections implemented from the first node to the second node in a first predetermined time and a second cumulative number of D2D connections from the second node to the first node;

Determining, according to the first accumulated number of times and the second accumulated number of times, a first weight and a second weight of the D2D connection between the first node and the second node;

Deleting the D2D connection from the network topology if the first weight or the second weight is less than zero;

Wherein the first weight ω ₁ = b ₁ v _c - b ₂ v _d , the second weight ω ₂ = b ₂ v _c - b ₁ v _d , v _d < v _c , the v _c represents the weight The cost of downloading data by the corresponding node through the cellular network, the v _d representing the cost of data sharing through the D2D connection, the b ₁ representing the first cumulative number of times, and the b ₂ representing the second cumulative number of times.

The resulting network topology is closer to reality, improving the accuracy of the network topology and improving the accuracy of network optimization.

Further, the determining, according to the deleted network topology, whether to continue to delete the D2D connection in the network topology or to increase the D2D connection in the network topology, specifically, if the deleted network topology is the The Nash equalization network topology ends; otherwise, it continues to delete the D2D connection in the network topology or increase the D2D connection in the network topology.

Further, the increasing the D2D connection in the network topology specifically includes: determining a third cumulative number of times of implementing the D2D connection from the third node to the fourth node in a second preset time and from the second node to The first node implements a fourth cumulative number of times of the D2D connection;

Determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a fourth weight of the D2D connection between the third node and the fourth node; wherein the third weight is used to indicate a weight of the D2D connection from the third node to the fourth node, the fourth weight being used to indicate a weight of the D2D connection from the fourth node to the third node;

And if the third weight and the fourth weight are both greater than zero, increasing a D2D connection between the third node and the fourth node to the network topology;

Wherein the third weight _{_{_{ω 3 = b 3 v c -b}}} 4 v d, the fourth weight _{_{_{ω 4 = b 4 v c -b}}} 3 v d, v _c represents the weight corresponding to the node through a cellular network The cost of downloading data, the v _d representing the cost of data sharing through a D2D connection, the b ₃ representing the third cumulative number of times, and the b ₄ representing the fourth cumulative number of times. By calculating the third weight and the fourth weight, it is possible to accurately determine whether to increase the D2D connection in the network topology.

The following describes an embodiment of the invention to provide a data storage device, wherein the device part corresponds to the above method, and the corresponding content technology has the same effect, and details are not described herein again.

In a third aspect, an embodiment of the present invention provides an apparatus for determining a network topology, including: a determining module, a calculating module, and a deleting module;

The determining module is configured to determine a network topology, where the network topology includes: N nodes and a device-to-device D2D connection between each pair of nodes, where N is an integer greater than or equal to 2, the node representation User terminal

The calculating module is configured to calculate a first weight of each of the two first nodes connected to each of the D2D connections, and calculate a second weight of each of the two first nodes after deleting the D2D connection ;

If the second weight of each of the two first nodes is greater than the corresponding first weight, the deleting module deletes the D2D connection between the two first nodes from the network topology;

The determining module is further configured to determine, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology, until the deleted or added network topology is a Nash balanced network. Topology;

Further, the apparatus further includes: adding a module; if the determining module determines that the deleted network topology is the Nash balanced network topology, ending; otherwise, the deleting module continues to delete the network topology The D2D connection in the or the add module increases the D2D connection in the network topology.

Further, the calculating module is further configured to calculate a third weight of each of the two second nodes that do not have a D2D connection, and after calculating a D2D connection between the two second nodes, calculate the a fourth weight of each of the two second nodes; if the fourth weight of each of the two second nodes is greater than the corresponding third weight, the adding module increases the D2D connection between the two second nodes to the The network topology.

Wherein the revenue of the node

cost

In a fourth aspect, an embodiment of the present invention provides an apparatus for determining a network topology, including: a determining module and a deleting module;

The determining module is used to:

If the first weight or the second weight is less than zero, the deleting module deletes the D2D connection from the network topology;

The determining module determines whether to continue deleting the D2D connection in the network topology or increasing the D2D connection in the network topology according to the deleted network topology, until the deleted or added network topology is a Nash balanced network topology;

Further, the device further includes: adding a module;

If the determining module determines that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, the deletion module continues to delete the D2D connection in the network topology or the add module increases the D2D connection in the network topology.

Further, the determining module is further configured to:

Determining a third cumulative number of times of implementing the D2D connection from the third node to the fourth node in a second preset time and a fourth cumulative number of times of implementing the D2D connection from the second node to the first node;

And if the third weight and the fourth weight are both greater than zero, the adding module increases a D2D connection between the third node and the fourth node to the network topology;

Wherein the third weight ω ₃ = b ₃ v _c - b ₄ v _d , the fourth weight ω ₄ = b ₄ v _c - b ₃ v _d , the v _c represents the node corresponding to the weight through the cellular network The cost of downloading data, the v _d representing the cost of data sharing through a D2D connection, the b ₃ representing the third cumulative number of times, and the b ₄ representing the fourth cumulative number of times.

In a fifth aspect, an embodiment of the present invention provides an apparatus for determining a network topology, including: a processor and a memory;

The memory is configured to store code to be executed by the processor;

The processor is used to:

Calculating a first weight of each of the two first nodes connected to each of the D2D connections, and calculating a second weight of each of the two first nodes after deleting the D2D connection;

Deleting a D2D connection between the two first nodes from the network topology if a second weight of each of the two first nodes is greater than a corresponding first weight;

Wherein the weight is determined by v _c , n ^to , v _d and n ^from , wherein the v _c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and the n ^to represents the weight from the other node to the node the expected value of the number of the corresponding node D2D connection can be achieved, v _d denotes the D2D connection costs by sharing data, n ^from the slave nodes represents the weight corresponding to the other nodes may be implemented D2D connection The expected value of the number.

Further, the processor is further configured to: if the deleted network topology is determined Ending for the Nash balanced network topology; otherwise, continuing to delete the D2D connection in the network topology or increase the D2D connection in the network topology.

Further, the processor is further configured to: calculate a third weight of each of the two second nodes that do not have a D2D connection, and calculate that after adding the D2D connection between the two second nodes a fourth weight of each of the two second nodes; if the fourth weight of each of the two second nodes is greater than the corresponding third weight, increasing a D2D connection between the two second nodes to the network Topology.

Wherein the revenue of the node

cost

In a sixth aspect, an embodiment of the present invention provides an apparatus for determining a network topology, including: a processor and a memory;

The memory is configured to store code to be executed by the processor;

The processor is used to:

Wherein the first weight ω ₁ = b ₁ v _c - b ₂ v _d , the second weight ω ₂ = b ₂ v _c - b ₁ v _d , v _d < v _c , the v _c represents the weight the cost of the corresponding node through the cellular network to download data, the D2D connection is represented by v _d cost of sharing data, the b ₁ represents the first cumulative number of the accumulation b ₂ represents the second frequency.

Further, the processor is further configured to: if it is determined that the deleted network topology is the Nash balanced network topology, end; otherwise, continue to delete the D2D connection in the network topology or increase the network topology. D2D connection.

Further, the processor is further configured to:

DRAWINGS

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

1 is a schematic diagram of a system architecture in which D2D technology is combined with cellular network technology;

2 is a flowchart of a method for determining a network topology structure according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for determining a network topology according to another embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an apparatus for determining a network topology structure according to an embodiment of the present invention; Figure

FIG. 5 is a schematic structural diagram of an apparatus for determining a network topology structure according to another embodiment of the present invention;

FIG. 6 is a schematic structural diagram of an apparatus for determining a network topology structure according to another embodiment of the present invention;

FIG. 7 is a schematic structural diagram of an apparatus for determining a network topology structure according to still another embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

Data sharing between devices can be achieved through cooperation between cellular networks and complementary network technologies. The data in the embodiment of the present invention may be a picture, a file, a web page, or the like. The cellular network technology here may be a 2G Global System for Mobile (GSM), Code Division Multiple Access (CDMA), or 3G Time Division-Synchronous Code. Division Multiple Access (TD-SCDMA), Wideband Code Division Multiple Access (WCDMA), and 4G Time-Division Long Term Evolution (TD-LTE), LTE- FDD, or related system systems after 4G.

The embodiments of the present invention are mainly based on the cooperation of the D2D technology and the cellular network technology for data sharing. For example, FIG. 1 is a schematic diagram of a system architecture combining D2D technology and cellular network technology, using a social network service (SNSs) to push a subscription service, in which a file provider (for example, a subscription public number) pushes a file. And N subscribers to obtain the file, wherein the subscriber has different delays in accessing the file content. Each subscriber is a separate user terminal and can establish long-term D2D sharing protocols with other user terminals.

In the prior art, it is assumed that there is a D2D connection between each user terminal, based on such a network extension. The structure is implemented to optimize the network, for example, the network bandwidth is maximized or the delay is minimized. However, in reality, there may be “selfish” user terminals, and these “selfish” user terminals will not Share your own data to all user terminals or any user terminal. For example, as shown in FIG. 1, the user terminal B and the user terminal D directly download data through the cellular network, and the user terminal B only shares data to the user terminal A through the D2D connection, and the user terminal C is waiting to establish a D2D connection with other user terminals. Get the file. Therefore, the network topology in the actual situation is not that there may be a D2D connection between any two user terminals. Therefore, the network topology in the prior art is not accurate enough, thereby reducing the accuracy of network optimization.

In order to solve the technical problem in the prior art, the embodiment of the present invention provides a method for determining a network topology, and FIG. 2 is a flowchart of a method for determining a network topology according to an embodiment of the present invention. The main body is a smart device such as a computer, a mobile phone or a tablet computer, and the method specifically includes the following processes:

S201: Determine a network topology, where the network topology includes: N nodes and a device-to-device D2D connection between each pair of nodes, where N is an integer greater than or equal to 2, and the node represents a user terminal;

S202: Calculate a first weight of each of the two first nodes connected to each D2D connection, and calculate a second weight of each of the two first nodes after deleting the D2D connection;

Specifically, the weight is determined by v _c , n ^to , v _{d ,} and n ^from , where v _c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and n ^to represents a node corresponding to the weight from the other node The expected value of the number of D2D connections that can be implemented, v _d represents the cost of data sharing by D2D connection, and n ^from represents the expected value of the number of D2D connections that can be implemented from the node corresponding to the weight to other nodes.

The method of calculating the weight can be as follows:

The first alternative method is: the weight is the difference between the profit g of the node corresponding to the weight and the cost c; wherein, the profit of the node g=v _c ·n ^to , the cost c=v _d ·n ^from , v _d <v _c The v _c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and the n ^to represents an expected value of the number of D2D connections achievable from the other node to the node corresponding to the weight, the v _d D2D connection represented by the cost of sharing data, the expected value of the number represented by n ^from the connecting node from the weights corresponding to other nodes D2D achievable. Wherein, since the access delay of each user terminal is different, the expected value of the number of D2D connections that can be implemented from other nodes to the node corresponding to the weight is achievable with the node corresponding to the weight to other nodes. Expected values for D2D connections are usually different.

Specifically, for a network topology, the set of nodes is Ω, and for each node _{i ∈} Ω, φ _i (G) is the weight of node i in the network topology G. Since the sharing protocol of D2D communication is a bilateral contact process, it means that the user terminal status is equal in the actual sharing process, and the connection between user terminals can be represented by undirected edges. In addition, it is assumed that in the network topology G Allow for cyclical and multilateral situations. The above network topology G will be an undirected simple graph, assuming that G ⁱ represents the maximum connected subgraph containing node i, ie

Is a connection subgraph containing node i, and is arbitrary for containing node i

There are V(G') ≤ V(G ⁱ ), and V(·) represents the set of nodes involved.

In the embodiment of the present invention, the weight φ _i (G) of each user _i ∈ Ω is defined. Generally, for any node i ∈ Ω, the weight is positively correlated with the benefit g _i , and is inversely related to the cost c _i . Simple, for any network topology G, we can define the weight of the node i∈Ω as follows:

φ _i (G)=g _i (G)-c _i (G)

It should be pointed out that only nodes that establish a connection with the node i∈Ω will have an impact on the data sharing performance, so the weight can be written as φ _i (G ⁱ )=g _i (G ⁱ )-c _i (G ⁱ ).

Due to the complexity of the network structure, it is usually very difficult to calculate φ _i (G ⁱ ) rigorously. In order to simplify the operation, we assume that there is only one hop D2D connection in the network topology, so that the estimated φ _i (G ⁱ ) is calculated. There is a hop that can be written as φ _i (S ⁱ ). Thus for the network topology G and any node i ∈ Ω, we use the set S _i ={j ∈Ω|e _ij ∈E(G)} to represent all adjacent nodes connected to the node i, we denote these nodes as

And assume that their access delay is

The definition of access delay is given below: the so-called access delay refers to the time from the generation of the data to be shared to the receipt of the shared data by the user terminal. For example, in the push subscription application, the subscribers access at different frequencies. Services thus create different delays, which are often related to the subscriber's personal habits. We assume that the file provider always generates a file at time t=0, and uses a _i to represent the access delay of node i, then a _i is a random variable distributed in [0, +∞), the probability distribution of this random variable The Probability Distribution Function (PDF) is determined by the lifestyle of node i. To model the PDF of the random variable a _i , we use Weibull Distribution to represent the access delay, ie:

among them

Representing the probability distribution function, the constant k _i >0 determines the PDF shape of the random variable a _i . For example, when k _{i is} large, a _{i is} concentrated at a position where the PDF is relatively high. The parameter λ _i >0 is a parameter that roughly determines the expected value of a _i , for example, the higher the λ _{i , the} higher a _i . We assume that the access delay {a _i |i∈Ω} is randomly independent.

Then, it can be found that only the node {a _l }, 1 ≤ _l ≤ h can download the file and transmit it to the node i through the D2D connection. By comparing the complex operation, we can calculate not share any node where the file node i to node i at time probability a _i directly through the cellular network is downloading files until time a _i:

among them

Representing the probability that at least one of the nodes i and j meets at least once in the time period Δt. Specifically, in some studies, different motion patterns of the user terminal have been explored, and for a pair of user terminals, the time axis can be divided. For contact time and non-contact time. Contact time means that two user terminals are within D2D communication range of each other, so that they can perform D2D to share data; non-contact time refers to time between two contact time periods.

Where, b _{i,j is used to} indicate the non-contact time of the two users, which is subject to Pareto Distribution,

The constant α _i,j >1 determines the PDF shape of the random variable b _i,j . For example, when α _{ij is} large, b _{ij is} concentrated in the lower value of the PDF. And τ _ij> 0 determines the minimum value of random variables b _{i, j} is. And assume that each non-contact time {b _i,j |i,j∈Ω} is randomly independent.

According to the above formula, we can estimate the gain and cost of node i. For node i∈Ω, the benefits, costs and weights are as follows:

g _i (S ⁱ )=v _c ·(1-p _i,i )·S _i

φ _i (S ⁱ )=g _i (S ⁱ )-c _i (S ⁱ )

In the process of implementing machine D2D communication, data sharing is performed through a tree structure in a cellular network system, thereby ensuring that the number of connections of cellular communication and D2D communication is limited. Such multi-hop D2D communication is not considered in the above calculation, but it is reflected in the final result, that is, while the number of connections of D2D communication increases, the number of cellular network communication will decrease accordingly. Since v _d <v _c , the overall benefit of G ⁱ is underestimated, ie

Therefore, the above φ _i (S ⁱ ) is the weight value in the worst case, and the weight of the actual calculation is more important than the worst case described above. It should be noted that (1-p _i,i )·S _{i is} the n ^{to of} the node i, and represents the expected value of the number of D2D connections that can be realized from other nodes to the node i.

That is, n ^from the node i indicates the expected value of the number of D2D connections that can be implemented from the node i to other nodes.

a second optional manner: the weight is a difference between a revenue g of the node corresponding to the weight and a cost c; wherein the revenue of the node

cost

v _d <v _c ; the v _c represents the cost of downloading data by the node corresponding to the weight through the cellular network, and the n ^to represents the expected value of the number of D2D connections achievable from the other node to the node corresponding to the weight The v _d represents a cost of data sharing by a D2D connection, and the n ^from represents an expected value of the number of D2D connections that can be implemented from the node corresponding to the weight to other nodes, and ω _i represents the node corresponding to the weight The preference weight for node i, ω _j represents the preference weight of the node corresponding to the weight to node j.

Specifically, n ^to and n ^from have given the determination method in the first alternative manner, and ω _i and ω _j can be given according to actual conditions, for example, node i is very willing to share its own data to user j, then The weight can be 0.9. The present invention does not limit the method of determining ω _i and ω _j .

S203: If the second weight of each of the two first nodes is greater than the corresponding first weight, deleting the D2D connection between the two first nodes from the network topology;

S204: Determine, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology, until the deleted or added network topology is a Nash balanced network topology.

Referring to step S203 and step S204, since the user terminal may be constantly moving, that is, its state information is constantly changing, the network topology is dynamically adjusted continuously, and two firsts are deleted in step S203. After the D2D connection between the nodes, it is determined whether the deleted network topology is a Nash balanced network topology. If yes, the end indicates that the current network topology is relatively stable. If not, the D2D in the network topology is deleted. Connect or increase the D2D connection in the network topology until the deleted or added network topology is a Nash balanced network topology.

The increasing the D2D connection in the network topology includes: calculating a third weight of each of the two second nodes that do not have a D2D connection, and adding a D2D connection between the two second nodes Calculating a fourth weight of each of the two second nodes; The fourth weight of each of the second nodes is greater than the corresponding third weight, and the D2D connection between the two second nodes is increased to the network topology.

Specifically, the method for calculating the third weight and the fourth weight is the same as the method for calculating the weight in S202, and details are not described herein again.

An embodiment of the present invention provides a method for determining a network topology. First, determining a network topology, where the network topology includes: N nodes and device-to-device D2D connections between each pair of nodes, and then, by calculating each node. Weight to measure whether to delete or increase the D2D connection between nodes. Since the weight is determined by v _c , n ^to , v _d and n ^from , the cost of downloading data through the cellular network, from other nodes to the node corresponding to the weight The expected value of the number of achievable D2D connections, the cost of data sharing through the D2D connection, and the expected value of the number of D2D connections achievable from the node corresponding to the weight to other nodes can be understood as the user. The "selfishness" of the terminal is taken into account. For example, when the user terminal is unwilling to share its own data to other user terminals, that is, the user terminal is relatively selfish, the cost of data sharing through the D2D connection can be increased. The resulting network topology is closer to reality, improving the accuracy of the network topology. Improve the accuracy of network optimization.

In the above embodiment, the weight of the node is used to determine whether to delete or increase the D2D connection between the nodes. The following describes a method for determining whether to delete or increase the D2D connection between the nodes based on the historical data between the nodes, as follows:

FIG. 3 is a flowchart of a method for determining a network topology according to another embodiment of the present invention. As shown in FIG. 3, the method includes the following processes:

S301: Determine a network topology, where the network topology includes: N nodes and a device-to-device D2D connection between each pair of nodes, where N is an integer greater than or equal to 2, and the node represents a user terminal;

S302: determining a first cumulative number of D2D connections implemented from the first node to the second node in a first preset time and a second cumulative number of D2D connections implemented from the second node to the first node;

Specifically, since the user terminal may be constantly moving, the D2D connection between the user terminals may sometimes exist, sometimes does not exist, and in addition, since the access delay of each user terminal is different, from the first node to The first cumulative number of D2D connections implemented by the second node and the second cumulative number of D2D connections implemented from the second node to the first node may be different.

S303: Determine, between the first node and the second node, according to the first accumulated number of times and the second accumulated number of times The first weight and the second weight of the D2D connection;

S304: If the first weight or the second weight is less than zero, the D2D connection is deleted from the network topology.

S305: Determine, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology, until the deleted or added network topology is a Nash balanced network topology.

The determining, according to the deleted network topology, whether to continue to delete the D2D connection in the network topology or to increase the D2D connection in the network topology, the method includes: if the deleted network topology is the Nash balanced network The topology ends; otherwise, it continues to delete D2D connections in the network topology or increase D2D connections in the network topology.

Specifically, since the user terminal may be constantly moving, that is, its state information is constantly changing, the network topology is continuously dynamically adjusted, and dynamically adjusting the network topology includes: deleting or adding a D2D connection.

Further, the increasing the D2D connection in the network topology specifically includes: determining a third cumulative number of times that the D2D connection is implemented from the third node to the fourth node in a second preset time, and from the second node to the second Determining, by a node, a fourth cumulative number of times of the D2D connection; determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a third weight of the D2D connection between the third node and the fourth node Four weights; wherein the third weight is used to represent a weight of a D2D connection from the third node to the fourth node, and the fourth weight is used to represent from the fourth node to the third a node, a weight of the D2D connection; if the third weight and the fourth weight are both greater than zero, increasing a D2D connection between the third node and the fourth node to the network topology; The third weight ω ₃ = b ₃ v _c - b ₄ v _d , the fourth weight ω ₄ = b ₄ v _c - b ₃ v _d , the v _c indicating that the node corresponding to the weight downloads data through the cellular network cost, as represented by v _d of the D2D connection for data sharing , B ₃ indicates the cumulative number of times the third, the fourth b ₄ represent the number of accumulated.

An embodiment of the present invention provides a method for determining a network topology. First, determining a network topology, where the network topology includes: N nodes and device-to-device D2D connections between each pair of nodes, where N is greater than or An integer equal to 2, the node represents a user terminal, and then determining whether to delete the D2D connection by calculating a first weight and a second weight of the D2D connection, and determining whether to continue deleting the network topology according to the deleted network topology The D2D connection or the D2D connection in the network topology is added until the deleted or added network topology is a Nash balanced network topology. Since the first weight ω ₁ = b ₁ v _c - b ₂ v _d , the second weight ω ₂ = b ₂ v _c - b ₁ v _d , v _c represents the cost of the node corresponding to the weight to download data through the cellular network, The v _d represents a cost of data sharing through a D2D connection, the b ₁ represents the first accumulated number of times, and the b ₂ represents the second accumulated number of times, which can be understood as considering the “selfishness” of the user terminal. In the following, for example, when the user terminal is unwilling to share its own data to other user terminals, that is, the user terminal is relatively selfish, the cost of data sharing through the D2D connection can be increased, so that the finally obtained network topology is closer. In practice, the accuracy of the network topology is improved, thereby improving the accuracy of network optimization.

FIG. 4 is a schematic structural diagram of an apparatus for determining a network topology structure according to an embodiment of the present invention. The device is a smart device such as a computer, a mobile phone, or a tablet computer, and the device includes: a determining module 401, a calculating module 402, and a deleting module 403. ;

The determining module 401 is configured to determine a network topology, where the network topology includes: N nodes and device-to-device D2D connections between each pair of nodes, where N is an integer greater than or equal to 2, the node Representing a user terminal;

The calculating module 402 is configured to calculate a first weight of each of the two first nodes connected to each of the D2D connections, and calculate a second of each of the two first nodes after deleting the D2D connection Weights;

If the second weight of each of the two first nodes is greater than the corresponding first weight, the deleting module 403 deletes the D2D connection between the two first nodes from the network topology;

The determining module 401 is further configured to determine, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology, until the deleted or added network topology is a Nash equilibrium. Network Topology;

Further, the device further includes an adding module 404; if the determining module 401 determines that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, the delete module 403 continues to delete the D2D connection in the network topology or the add module 404 increases the D2D connection in the network topology.

Further, the calculating module 402 is further configured to calculate a third weight of each of the two second nodes that do not have a D2D connection, and assuming that the D2D connection between the two second nodes is increased, Describe the fourth weight of each of the two second nodes;

If the fourth weight of each of the two second nodes is greater than the corresponding third weight, the adding module 404 increases the D2D connection between the two second nodes to the network topology.

Optionally, the weight is a difference between a revenue g of the node corresponding to the weight and a cost c; wherein the profit of the node is g=v _c ·n ^to , and the cost is c=v _d ·n ^from , v _d <v _c .

Optionally, the weight is a difference between a revenue g of the node corresponding to the weight and a cost c; wherein, the revenue of the node

cost

The present invention provides a device for determining a network topology. The device may be used to perform the method steps in the embodiment shown in FIG. 2, and the implementation principle and technical effects are similar, and details are not described herein again.

FIG. 5 is a schematic structural diagram of an apparatus for determining a network topology, which is a smart device such as a computer, a mobile phone, a tablet computer, and the like, and the device includes: a determining module 501 and a deleting module 502;

The determining module 501 is configured to: determine a network topology, where the network topology includes: N nodes and a device-to-device D2D connection between each pair of nodes, where N is an integer greater than or equal to 2, the node Determining a user terminal; determining a first cumulative number of D2D connections implemented from the first node to the second node in a first preset time and a second cumulative number of D2D connections implemented from the second node to the first node; Determining, by the first accumulated number of times and the second accumulated number of times, a first weight and a second weight of the D2D connection between the first node and the second node;

If the first weight or the second weight is less than zero, the deleting module 502 deletes the D2D connection from the network topology;

The determining module 501 determines, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increasing the D2D connection in the network topology, until the deleted or added network topology is a Nash balanced network topology. ;

Further, the device further includes: an adding module 503; if the determining module 501 determines that the deleted network topology is the Nash balanced network topology, ending; otherwise, the deleting module 502 continues to delete the network topology. The D2D connection in the structure or the add module 503 increases the D2D connection in the network topology.

Further, the determining module 501 is further configured to: determine a third cumulative number of times that the D2D connection is implemented from the third node to the fourth node in a second preset time, and implement from the second node to the first node. Determining a fourth cumulative number of times of the D2D connection; determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a fourth weight of the D2D connection between the third node and the fourth node; The third weight is used to indicate a weight of a D2D connection from the third node to the fourth node, and the fourth weight is used to indicate a D2D connection from the fourth node to the third node. a weighting; if the third weight and the fourth weight are both greater than zero, the adding module 503 increases a D2D connection between the third node and the fourth node to the network topology;

The present invention provides an apparatus for determining a network topology, which may be used to perform the method steps in the embodiment shown in FIG. 3, and the implementation principle and technical effects are similar, and details are not described herein again.

FIG. 6 is a schematic structural diagram of an apparatus for determining a network topology structure according to another embodiment of the present invention. The device is a smart device such as a computer, a mobile phone, or a tablet computer, and the device includes: a processor 601 and a memory 602;

The memory 602 is configured to store code to be executed by the processor 601;

The processor 601 is configured to:

Further, the processor 601 is further configured to: if it is determined that the deleted network topology is the Nash balanced network topology, end; otherwise, continue to delete the D2D connection or increase the network in the network topology. D2D connection in the topology.

Further, the processor 601 is further configured to:

Calculating a third weight of each of the two second nodes that do not have a D2D connection, and calculating a fourth weight of each of the two second nodes after adding a D2D connection between the two second nodes;

And if the fourth weight of each of the two second nodes is greater than the corresponding third weight, increasing a D2D connection between the two second nodes to the network topology.

Wherein the revenue of the node

cost

FIG. 7 is a schematic structural diagram of an apparatus for determining a network topology structure according to still another embodiment of the present invention. The device is a smart device such as a computer, a mobile phone, a tablet computer, and the like, and the device includes: a processor 701 and a memory 702;

The memory 702 is configured to store a code to be executed by the processor 701;

The processor 701 is configured to:

Further, the processor 701 is further configured to: if it is determined that the deleted network topology is the Nash balanced network topology, end; otherwise, continue to delete the D2D connection in the network topology or increase the network topology. D2D connection in.

Further, the processor 701 is further configured to:

Determining the third node and the first number according to the third cumulative number of times and the fourth cumulative number of times a third weight and a fourth weight of the D2D connection between the four nodes; wherein the third weight is used to represent a weight of the D2D connection from the third node to the fourth node, and the fourth weight is used Representing the weight of the D2D connection from the fourth node to the third node;

One of ordinary skill in the art will appreciate that all or part of the steps to implement the various method embodiments described above may be accomplished by hardware associated with the program instructions. The aforementioned program can be stored in a computer readable storage medium. The program, when executed, performs the steps including the foregoing method embodiments; and the foregoing storage medium includes various media that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A method for determining a network topology, comprising:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Calculating a first weight of each of the two first nodes connected to each of the D2D connections, and calculating a second weight of each of the two first nodes after deleting the D2D connection;

Deleting a D2D connection between the two first nodes from the network topology if a second weight of each of the two first nodes is greater than a corresponding first weight;

Determine whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology according to the deleted network topology until the deleted or added network topology is a Nash balanced network topology;

Wherein the weight is determined by v c , n to , v d and n from , wherein the v c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and the n to represents the weight from the other node to the node The expected value of the number of D2D connections that can be implemented by the corresponding node, the v d represents the cost of data sharing through the D2D connection, and the n from represents the D2D connection that can be implemented from the node corresponding to the weight to the other node. The expected value of the number.
The method according to claim 1, wherein the determining whether to continue deleting the D2D connection in the network topology or increasing the D2D connection in the network topology according to the deleted network topology includes:

If the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, continue to delete the D2D connection in the network topology or increase the D2D connection in the network topology.
The method according to claim 1 or 2, wherein the increasing the D2D connection in the network topology comprises:

Calculating a third weight of each of the two second nodes that do not have a D2D connection, and calculating a fourth weight of each of the two second nodes after adding a D2D connection between the two second nodes;

If the fourth weight of each of the two second nodes is greater than the corresponding third weight, then adding A D2D connection between the two second nodes is connected to the network topology.
The method according to any one of claims 1 to 3, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein, the profit of the node g=v c ·n to , the cost c=v d ·n from , v d <v c .
The method according to any one of claims 1 to 3, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein the revenue of the node
cost
v d <v c , ω i represents the preference weight of the node corresponding to the weight to the node i, and ω j represents the preference weight of the node corresponding to the weight to the node j.
A method for determining a network topology, comprising:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Determining a first cumulative number of D2D connections implemented from the first node to the second node in a first predetermined time and a second cumulative number of D2D connections from the second node to the first node;

Determining, according to the first accumulated number of times and the second accumulated number of times, a first weight and a second weight of the D2D connection between the first node and the second node;

Deleting the D2D connection from the network topology if the first weight or the second weight is less than zero;

Determine whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology according to the deleted network topology until the deleted or added network topology is a Nash balanced network topology;

Wherein the first weight ω 1 = b 1 v c - b 2 v d , the second weight ω 2 = b 2 v c - b 1 v d , v d < v c , the v c represents the weight The cost of downloading data by the corresponding node through the cellular network, the v d representing the cost of data sharing through the D2D connection, the b 1 representing the first cumulative number of times, and the b 2 representing the second cumulative number of times.
The method according to claim 6, wherein the determining whether to continue deleting the D2D connection in the network topology or increasing the D2D connection in the network topology according to the deleted network topology includes:

If the deleted network topology is the Nash balanced network topology, the junction bundle;

Otherwise, continue to delete the D2D connection in the network topology or increase the D2D connection in the network topology.
The method according to claim 6 or 7, wherein the increasing the D2D connection in the network topology comprises:

Determining a third cumulative number of times of implementing the D2D connection from the third node to the fourth node in a second preset time and a fourth cumulative number of times of implementing the D2D connection from the second node to the first node;

Determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a fourth weight of the D2D connection between the third node and the fourth node; wherein the third weight is used to indicate a weight of the D2D connection from the third node to the fourth node, the fourth weight being used to indicate a weight of the D2D connection from the fourth node to the third node;

And if the third weight and the fourth weight are both greater than zero, increasing a D2D connection between the third node and the fourth node to the network topology;

Wherein the third weight ω 3 = b 3 v c - b 4 v d , the fourth weight ω 4 = b 4 v c - b 3 v d , the v c represents the node corresponding to the weight through the cellular network The cost of downloading data, the v d representing the cost of data sharing through a D2D connection, the b 3 representing the third cumulative number of times, and the b 4 representing the fourth cumulative number of times.
An apparatus for determining a network topology, comprising: a determining module, a calculating module, and a deleting module;

The determining module is configured to determine a network topology, where the network topology includes: N nodes and a device-to-device D2D connection between each pair of nodes, where N is an integer greater than or equal to 2, the node representation User terminal

The calculating module is configured to calculate a first weight of each of the two first nodes connected to each of the D2D connections, and calculate a second weight of each of the two first nodes after deleting the D2D connection ;

If the second weight of each of the two first nodes is greater than the corresponding first weight, the deleting module deletes the D2D connection between the two first nodes from the network topology;

The determining module is further configured to determine, according to the deleted network topology, whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology, until the deleted or added network topology is a Nash balanced network. Topology;

Wherein the weight is determined by v c , n to , v d and n from , wherein the v c represents a cost of downloading data by the node corresponding to the weight through the cellular network, and the n to represents the weight from the other node to the node The expected value of the number of D2D connections that can be implemented by the corresponding node, the v d represents the cost of data sharing through the D2D connection, and the n from represents the D2D connection that can be implemented from the node corresponding to the weight to the other node. The expected value of the number.
The device according to claim 9, further comprising: an adding module;

If the determining module determines that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, the deletion module continues to delete the D2D connection in the network topology or the add module increases the D2D connection in the network topology.
Device according to claim 9 or 10, characterized in that

The calculating module is further configured to calculate a third weight of each of the two second nodes that do not have a D2D connection, and calculate the two seconds after adding a D2D connection between the two second nodes The fourth weight of each node;

If the fourth weight of each of the two second nodes is greater than the corresponding third weight, the adding module increases the D2D connection between the two second nodes to the network topology.
The apparatus according to any one of claims 9-11, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein, the profit of the node g=v c ·n to , the cost c=v d ·n from , v d <v c .
The apparatus according to any one of claims 9-11, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein the revenue of the node
cost
v d <v c, ω i represents the weight preference weights corresponding to nodes of node i weight, ω j represents preference weights corresponding to the right node of the node j of weight.
An apparatus for determining a network topology, comprising: a determining module and a deleting module;

The determining module is used to:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Determining a first cumulative number of D2D connections implemented from the first node to the second node in a first predetermined time and a second cumulative number of D2D connections from the second node to the first node;

Determining, according to the first accumulated number of times and the second accumulated number of times, a first weight and a second weight of the D2D connection between the first node and the second node;

If the first weight or the second weight is less than zero, the deleting module deletes the D2D connection from the network topology;

The determining module determines whether to continue deleting the D2D connection in the network topology or increasing the D2D connection in the network topology according to the deleted network topology, until the deleted or added network topology is a Nash balanced network topology;

Wherein the first weight ω 1 = b 1 v c - b 2 v d , the second weight ω 2 = b 2 v c - b 1 v d , v d < v c , the v c represents the weight The cost of downloading data by the corresponding node through the cellular network, the v d representing the cost of data sharing through the D2D connection, the b 1 representing the first cumulative number of times, and the b 2 representing the second cumulative number of times.
The device according to claim 14, further comprising: an adding module;

If the determining module determines that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, the deletion module continues to delete the D2D connection in the network topology or the add module increases the D2D connection in the network topology.
Device according to claim 14 or 15, characterized in that

The determining module is further configured to:

Determining a third cumulative number of times of implementing the D2D connection from the third node to the fourth node in a second preset time and a fourth cumulative number of times of implementing the D2D connection from the second node to the first node;

Determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a fourth weight of the D2D connection between the third node and the fourth node; wherein the third weight is used to indicate a weight of the D2D connection from the third node to the fourth node, the fourth weight being used to indicate a weight of the D2D connection from the fourth node to the third node;

And if the third weight and the fourth weight are both greater than zero, the adding module increases a D2D connection between the third node and the fourth node to the network topology;

Wherein the third weight ω 3 = b 3 v c - b 4 v d , the fourth weight ω 4 = b 4 v c - b 3 v d , the v c represents the node corresponding to the weight through the cellular network The cost of downloading data, the v d representing the cost of data sharing through a D2D connection, the b 3 representing the third cumulative number of times, and the b 4 representing the fourth cumulative number of times.
An apparatus for determining a network topology, comprising: a processor and a memory;

The memory is configured to store code to be executed by the processor;

The processor is used to:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Calculating a first weight of each of the two first nodes connected to each of the D2D connections, and calculating a second weight of each of the two first nodes after deleting the D2D connection;

Deleting a D2D connection between the two first nodes from the network topology if a second weight of each of the two first nodes is greater than a corresponding first weight;

Determine whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology according to the deleted network topology until the deleted or added network topology is a Nash balanced network topology;

Wherein the weight by v c, n to, v d and n from determining the cost of v c represents the weight corresponding to the node through the cellular network to download data from the n to the other node represents the weight to the right The expected value of the number of D2D connections that can be implemented by the corresponding node, the v d represents the cost of data sharing through the D2D connection, and the n from represents the D2D connection that can be implemented from the node corresponding to the weight to the other node. The expected value of the number.
The device according to claim 17, wherein the processor is further configured to:

If it is determined that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, continue to delete the D2D connection in the network topology or increase the D2D connection in the network topology.
The device according to claim 17 or 18, wherein the processor is further configured to:

Calculating a third weight of each of the two second nodes that do not have a D2D connection, and calculating a fourth of each of the two second nodes after adding a D2D connection between the two second nodes Weights;

And if the fourth weight of each of the two second nodes is greater than the corresponding third weight, increasing a D2D connection between the two second nodes to the network topology.
The apparatus according to any one of claims 17 to 19, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein, the profit of the node g=v c ·n to , the cost c=v d ·n from , v d <v c .
The apparatus according to any one of claims 17 to 19, wherein the weight is a difference between a revenue g of the node corresponding to the weight and a cost c;

Wherein the revenue of the node
cost
v d <v c , ω i represents the preference weight of the node corresponding to the weight to the node i, and ω j represents the preference weight of the node corresponding to the weight to the node j.
An apparatus for determining a network topology, comprising: a processor and a memory;

The memory is configured to store code to be executed by the processor;

The processor is used to:

Determining a network topology, the network topology comprising: N nodes and a device-to-device D2D connection between each pair of nodes, the N being an integer greater than or equal to 2, the node representing a user terminal;

Determining a first cumulative number of D2D connections implemented from the first node to the second node in a first predetermined time and a second cumulative number of D2D connections from the second node to the first node;

Determining, according to the first accumulated number of times and the second accumulated number of times, a first weight and a second weight of the D2D connection between the first node and the second node;

Deleting the D2D connection from the network topology if the first weight or the second weight is less than zero;

Determine whether to continue deleting the D2D connection in the network topology or increase the D2D connection in the network topology according to the deleted network topology until the deleted or added network topology is a Nash balanced network topology;

Wherein the first weight ω 1 = b 1 v c - b 2 v d , the second weight ω 2 = b 2 v c - b 1 v d , v d < v c , the v c represents the weight The cost of downloading data by the corresponding node through the cellular network, the v d representing the cost of data sharing through the D2D connection, the b 1 representing the first cumulative number of times, and the b 2 representing the second cumulative number of times.
The device according to claim 22, wherein the processor is further configured to:

If it is determined that the deleted network topology is the Nash balanced network topology, the process ends;

Otherwise, continue to delete the D2D connection in the network topology or increase the D2D connection in the network topology.
The device according to claim 22 or 23, wherein the processor is further configured to:

Determining a third cumulative number of times of implementing the D2D connection from the third node to the fourth node in a second preset time and a fourth cumulative number of times of implementing the D2D connection from the second node to the first node;

Determining, according to the third cumulative number of times and the fourth cumulative number of times, a third weight and a fourth weight of the D2D connection between the third node and the fourth node; wherein the third weight is used to indicate a weight of the D2D connection from the third node to the fourth node, the fourth weight being used to indicate a weight of the D2D connection from the fourth node to the third node;

And if the third weight and the fourth weight are both greater than zero, increasing a D2D connection between the third node and the fourth node to the network topology;

Wherein the third weight ω 3 = b 3 v c -b 4 v d, the fourth weight ω 4 = b 4 v c -b 3 v d, v c represents the weight corresponding to the node through a cellular network The cost of downloading data, the v d representing the cost of data sharing through a D2D connection, the b 3 representing the third cumulative number of times, and the b 4 representing the fourth cumulative number of times.